103 results on '"Reginald I. Low"'
Search Results
2. CHALLENGES OF PERCUTANEOUS CORONARY INTERVENTION IN A POLYTRAUMA PATIENT WITH CARDIAC CONTUSION
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Gordon Wong, Andrea Soares, Surabhi Madhwal Atreja, Hee Kong Fong, Lily Chen, and Reginald I. Low
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Cardiology and Cardiovascular Medicine - Published
- 2023
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3. Outcomes of primary percutaneous coronary intervention in acute myocardial infarction due to unprotected left main thrombosis: The Asia-Pacific Left Main ST-Elevation Registry (ASTER)
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Yangsoo Jang, Kelvin Chua, Choong Hou Koh, Myeong Ki Hong, Jung Sun Kim, Kendrick A. Shunk, Gagan D. Singh, Reginald I. Low, Krishan Soni, Stephen W. Waldo, Jonathan Yap, Ehrin J. Armstrong, Khung Keong Yeo, and Alvin Neo
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Left Main Coronary Artery Stenosis ,030204 cardiovascular system & hematology ,Culprit ,03 medical and health sciences ,Percutaneous Coronary Intervention ,0302 clinical medicine ,Risk Factors ,Internal medicine ,Republic of Korea ,Odds Ratio ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Registries ,cardiovascular diseases ,030212 general & internal medicine ,Myocardial infarction ,Coronary Artery Bypass ,Aged ,Retrospective Studies ,Singapore ,business.industry ,ST elevation ,Mortality rate ,Percutaneous coronary intervention ,Middle Aged ,medicine.disease ,Coronary Vessels ,United States ,Treatment Outcome ,surgical procedures, operative ,Conventional PCI ,Cardiology ,ST Elevation Myocardial Infarction ,Female ,Cardiology and Cardiovascular Medicine ,business ,TIMI - Abstract
Introduction Prior studies of ULM STEMI have been confined to small cohorts. Recent registry data with larger patient cohorts have shown contrasting results. We aim to study the outcomes of patients with unprotected left main (ULM) ST-elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI). Methods The Asia-pacific left main ST-Elevation Registry (ASTER) is a multicenter retrospective registry involving 4 sites in Singapore, South Korea, and the United States. The registry included patients presenting with STEMI due to an ULM coronary artery culprit lesion who underwent emergency PCI. The primary outcome was in-hospital mortality. Secondary outcomes included major adverse cardiovascular events. Results A total of 67 patients (mean age 64.2 ± 12.8 years, 53 [79.1%] males) were included. The distal left main bifurcation was most commonly involved (85%, n = 57). Fifty one (76%) patients had TIMI 3 flow post-PCI. The in-hospital mortality rate was 47.8% (n = 32); 61% (n = 41) had cardiac failure, 4% (n = 3) had emergency coronary artery bypass grafting, 1% (n = 1) had a re-infarction, 3% (n = 2) had stroke and 55% (n = 37) had malignant ventricular arrhythmias. On multivariate analysis, predictors of in-hospital mortality included older age (odds ratio (OR) 1.085 (95% confidence interval (CI) 1.002-1.175), P = 0.044), diabetes mellitus (OR 10.882 (95%CI 11.074-110.287), P = 0.043) and absence of post-PCI TIMI 3 flow (OR 71.429 (95%CI 2.985-1000), P = 0.008). Conclusions STEMI from culprit unprotected left main coronary artery stenosis is associated with significant mortality and morbidity. Emergency PCI provides an important treatment option in this high-risk group, but in-hospital mortality remains high.
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- 2017
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4. Accuracy and procedural characteristics of standard needle compared with radiofrequency needle transseptal puncture for structural heart interventions
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Dali Fan, Gagan D. Singh, Thomas W. Smith, Jason H. Rogers, Gaurav Sharma, and Reginald I. Low
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Catheter ablation ,General Medicine ,030204 cardiovascular system & hematology ,Heart septum ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Radiology, Nuclear Medicine and imaging ,030212 general & internal medicine ,Major complication ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Cardiac catheterization - Abstract
Objectives Our objectives were to assess for differences between standard and radiofrequency (RF) needle in procedural times, success, and spatial accuracy. Background Targeted transseptal (TS) puncture is essential for structural heart interventions. Spatial accuracy of standard versus RF needle has not been reported. Methods Consecutive patients undergoing structural heart interventions requiring TS puncture were studied retrospectively. A standard needle was alternated with a RF needle. Procedural success and times were recorded. Measurements based on intraprocedural transesophageal echocardiograms of the intended versus final TS crossing site were obtained. Pre-puncture and maximal tenting of the septum were also recorded. Results Twenty-five patients underwent standard needle and 27 RF TS access. All RF needle attempts to cross were successful without an assistance wire. Three standard needle patients required assisted crossing. After failed TS access, two patients had successful RF TS access. TS procedural times significantly favored the RF needle for time from septum to puncture (P = 0.02). Both standard and RF access yielded accurate crossing with no significant differences between the intended and actual crossing site. Maximal tenting was significantly less with the RF needle (P = 0.004). There were no major complications. Conclusions In the hands of an experienced operator, there were no major clinically significant differences between the standard and RF needle approaches. However, procedural unassisted crossing success was higher with the RF needle approach as compared to standard needle. Procedural times and degree of septum tenting favored the RF over standard needle. Accuracy was similar with both approaches. RF was a successful strategy when standard needle failed. There were no major complications with either TS puncture strategy. © 2016 Wiley Periodicals, Inc.
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- 2016
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5. Intraprocedural direct left atrial and wedge pressure correlation during transcatheter mitral valve repair: Results from a single center registry
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Dali Fan, Gagan D. Singh, Walter D. Boyd, William Wung, Thomas W. Smith, Neha Maheshwari Mantri, Maia L. Eng, Benjamin Stripe, Reginald I. Low, Jason H. Rogers, and Lily Chen
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Male ,medicine.medical_specialty ,Cardiac Catheterization ,Time Factors ,education ,Hemodynamics ,030204 cardiovascular system & hematology ,Single Center ,Prosthesis Design ,Severity of Illness Index ,Correlation ,03 medical and health sciences ,0302 clinical medicine ,Atrial Pressure ,Left atrial ,Internal medicine ,Monitoring, Intraoperative ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,030212 general & internal medicine ,Pulmonary Wedge Pressure ,Registries ,Pulmonary wedge pressure ,Aged ,Retrospective Studies ,Aged, 80 and over ,Heart Valve Prosthesis Implantation ,Mitral regurgitation ,business.industry ,MitraClip ,Mitral Valve Insufficiency ,General Medicine ,Treatment Outcome ,Heart Valve Prosthesis ,Cardiology ,Mitral Valve ,Transcatheter mitral valve repair ,Atrial Function, Left ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
OBJECTIVES This study investigates the correlation of occlusive wedge pressure (WP) with direct left atrial (LA) pressure in patients with severe mitral regurgitation (MR) undergoing transcatheter mitral valve repair (TMVr) with MitraClip. BACKGROUND There is interest in acquiring objective hemodynamic parameters for intraprocedural guidance in patients undergoing MitraClip. METHODS The study included 94 patients with severe MR at prohibitive surgical risk who underwent MitraClip at the University of California Davis Medical Center between 2014 and 2016. RESULTS An average of 1.8 ± 0.7 clips were used to achieve MR grade of 2+ or less in 99% of patients. Correlation analysis of all (n = 236) pre-clip, inter-clip, and final-clip WP and LA pressures yielded a Pearson's R (r) of 0.85 and 0.79 for mean WP vs mean LA and WP V vs LA V, respectively. Median LA V to mean LA ratio (LAV:mLA) was 1.75 (IQR 1.5-1.9). 79% (n = 74) of patients had LAV:mLA ratio ≥ 1.5 with associated WP V vs LA V correlation (r) of 0.83. In patients with LAV:mLA ratio
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- 2018
6. Prospective Multicenter Evaluation of the Direct Flow Medical Transcatheter Aortic Valve System
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Ivar Friedrich, Didier Tchetche, Giuseppe Bruschi, Francesco Maisano, Martyn Thomas, Federico De Marco, Jan Malte Sinning, Karl Eugen Hauptmann, Michael Lauterbach, Neil J. Weissman, Antonio Colombo, Jean Fajadet, Klaudija Bijuklic, Michael J. Mullen, Charles J. Davidson, Thierry Lefèvre, Christopher Young, Reginald I. Low, Michael Schmoeckel, Azeem Latib, Stefano Nava, Simon Redwood, Joachim Schofer, John Yap, Eberhard Grube, Silvio Klugmann, and Georg Nickenig
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Aortic valve ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Regurgitation (circulation) ,030204 cardiovascular system & hematology ,medicine.disease ,Surgery ,03 medical and health sciences ,Stenosis ,0302 clinical medicine ,medicine.anatomical_structure ,Valve replacement ,Internal medicine ,Aortic valve stenosis ,Cardiology ,Medicine ,030212 general & internal medicine ,Heart valve ,Cardiology and Cardiovascular Medicine ,business ,Stroke ,Cardiac catheterization - Abstract
Objectives The aim of this study was to assess the 1-year outcome after transcatheter aortic valve replacement (TAVR) of the Direct Flow Medical (DFM) valve in patients with severe symptomatic aortic stenosis who were contraindicated or high risk for surgery. Background The DFM transcatheter heart valve is a new-generation, nonmetallic aortic valve with a pressurized support structure and conformable double-ring annular sealing delivered through an 18-F sheath. The device allows repositioning, retrieval, and assessment of valve performance before permanent implantation. Methods A prospective multicenter European registry was set up to determine the safety and performance of the valve in 100 consecutive patients (10 centers). Echocardiographic and angiographic data were evaluated by an independent core laboratory, and adverse events were adjudicated by a clinical events committee using Valve Academic Research Consortium criteria. Results Patients were 83.1 ± 5.9 years of age and had a logistic EuroSCORE of 22.5 ± 11.3% and a Society of Thoracic Surgeons score of 9.7 ± 8.7%. Correct valve positioning was obtained in 99% of cases with a combined 30-day safety endpoint at 10%, including major stroke in 5.0%, major vascular complications in 2.0%, and death in 1%. At 12 months, 95% of patients were in New York Heart Association functional class I or II. Freedom from any death was 90%, and freedom from any death or major stroke was 85%. Echocardiography demonstrated none/trace to mild aortic regurgitation in 100% of patients and an unchanged mean aortic gradient of 12.2 ± 6.6 mm Hg and effective orifice area of 1.6 ± 0.4 cm 2 . Conclusions At 1 year, the DFM transcatheter heart valve had durable hemodynamics. This study demonstrates that the low rate of early complications and the low risk of significant aortic regurgitation translated into midterm clinical benefit.
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- 2016
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7. Long-term outcomes of angiographically confirmed coronary stent thrombosis: results from a multicentre California registry
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Reginald I. Low, Ehrin J. Armstrong, John S. MacGregor, Krishan Soni, Ryan Reeves, Jason H. Rogers, Khung Keong Yeo, Ehtisham Mahmud, Stephen W. Waldo, Kendrick A. Shunk, and Mitul Patel
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Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Myocardial Infarction ,Coronary Angiography ,California ,Coronary artery disease ,Percutaneous Coronary Intervention ,Coronary thrombosis ,Risk Factors ,Internal medicine ,Diabetes mellitus ,Coronary stent ,medicine ,Humans ,Registries ,Myocardial infarction ,Stroke ,Aged ,business.industry ,Coronary Thrombosis ,Percutaneous coronary intervention ,Drug-Eluting Stents ,Middle Aged ,medicine.disease ,Thrombosis ,Treatment Outcome ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
AIMS Limited data exist on long-term outcomes of patients with stent thrombosis (ST). Our aim was to describe the long-term outcomes after angiographically confirmed ST. METHODS AND RESULTS In this multicentre registry, consecutive cases of definite ST were identified between 2005 and 2013. Clinical and procedural characteristics, in-hospital outcomes and long-term survival up to five years were compared between those with and those without adverse cardiovascular and cerebrovascular events (MACCE), defined as all-cause mortality, myocardial infarction and stroke. Two hundred and twenty-one patients with 239 stent thrombosis events were identified. Patients who developed MACCE were older, less likely to be men, and less likely to have hypertension. Angiographic characteristics were similar. Patients who had a MACCE event showed a trend towards a lower likelihood of procedural success (86% vs. 91%, p=0.05). MACCE rates were 22% at one year and 41% at five years. All-cause mortality was 13% at one year and 24% at five years. On multivariable analysis, age, diabetes mellitus, active smoking and ST at a bifurcation were independently associated with the occurrence of MACCE up to five years. CONCLUSIONS Age, active smoking, diabetes mellitus and bifurcation disease are independently associated with long-term MACCE over a five-year follow-up period.
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- 2015
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8. Complex Case: Rota Gutter in RCA
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Reginald I. Low, Bradley D. Stauber, and Gagan D. Singh
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medicine.medical_specialty ,business.industry ,Conventional PCI ,medicine ,Rotational atherectomy ,Complication ,business ,Surgery - Abstract
A 75-year-old man with a history of CAD with prior CABG, DM, HTN, and CKD presented with NSTEMI. While the left-sided system was well revascularized, the graft to the RCA was occluded and the decision was made to perform PCI on the heavily calcified and tortuous RCA. With a “shepherd’s crook” at the proximal RCA, rotational atherectomy was attempted, but likely led to the complication of formation of a “gutter.” Guttering is a known complication of rotational atherectomy and can be treated conservatively or aggressively.
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- 2017
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9. Specials: Rotablation Through Stent Accordion
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Khung Keong Yeo, Reginald I. Low, and Garrett B. Wong
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Coronary angiography ,medicine.medical_specialty ,Ejection fraction ,Heavy alcohol use ,business.industry ,medicine.medical_treatment ,Stent ,medicine.disease ,Past history ,fluids and secretions ,Internal medicine ,cardiovascular system ,medicine ,Cardiology ,cardiovascular diseases ,Circumflex ,Severe stenosis ,business ,Dyslipidemia ,circulatory and respiratory physiology - Abstract
A 52-year-old man presented with NSTEMI. He had diabetes mellitus, hypertension, dyslipidemia, prior tobacco, and heavy alcohol use. He had a past history of CAD with CABG 3 years ago with LIMA to LAD, SVG to first diagonal, SVG to OM1, SVG to circumflex, and SVG to RCA. His LVEF was 35%. Coronary angiography showed severe native three-vessel disease, patent LIMA graft to the LAD, occluded SVGs to the OM1, RCA, and circumflex and severe stenosis in the SVG to the diagonal (Fig. 25.1, Videos 25.1 and 25.2) We proceed to intervene on the SVG-diagonal lesion.
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- 2017
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10. Overview of Equipment and Procedure
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Khung Keong Yeo, Tina Teo, Reginald I. Low, and Jonathan Yap
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Materials science ,Spring (mathematics) ,Composite material ,Rotation - Abstract
The RotaWire is very different from a standard coronary guidewire. Its construction prevents unravelling by the rotation of the burr. It is a 325 cm stainless steel, short spring-tipped guidewire. The shaft of the RotaWire is 0.009″. It tapers mainly in the last 13 cm proximal. The spring tip is 0.014″ in diameter and 2.2 cm in length and can be shaped (Fig. 1.1). There is also an extra-support RotaWire with a slightly longer tip (2.8 cm) and stiffer shaft (Fig. 1.2). The thicker wire tip also prevents the burr from going past the shaft of the wire. This is important in helping prevent inadvertent coronary artery perforations. The wire is very easy to kink. During advancement or removal or exchange of the burr, it is critical not to kink the wire. Kinking of the wire will result in difficulty removing or advancing the burr and can result in loss of wire position.
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- 2017
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11. Complex Case: Rotablation in Cardiogenic Shock
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Bradley D. Stauber, Gagan D. Singh, and Reginald I. Low
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medicine.medical_specialty ,Ischemic cardiomyopathy ,Ejection fraction ,business.industry ,medicine.medical_treatment ,Cardiogenic shock ,Cardiac index ,Hemodynamics ,medicine.disease ,Pulmonary edema ,Internal medicine ,cardiovascular system ,medicine ,Cardiology ,cardiovascular diseases ,Myocardial infarction ,business ,Intra-aortic balloon pump - Abstract
A 77-year-old man with a history of end-stage renal disease, ischemic cardiomyopathy (LVEF 30%) presented with a non-ST elevation myocardial infarction, and pulmonary edema. Initial right heart catheterization demonstrated that the patient was in cardiogenic shock, with systolic blood pressure of 90 mmHg and cardiac index of 1.5 L/min/m . Coronary angiography demonstrated a calcified left main as well a 90% proximal LAD and 95% circumflex lesion, and PCI was undertaken with rotational atherectomy. This case highlights that rotational atherectomy can be safely performed with experience, good technique, and appropriate planning including hemodynamic support with an intra-aortic balloon pump.
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- 2017
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12. Complex Case: Rotational Atherectomy Involving the Left Main Coronary Artery
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Reginald I. Low, Bradley D. Stauber, and Gagan D. Singh
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Rotational atherectomy ,medicine.disease ,Coronary arteries ,Stenosis ,surgical procedures, operative ,medicine.anatomical_structure ,Internal medicine ,Conventional PCI ,Angiography ,cardiovascular system ,medicine ,Cardiology ,cardiovascular diseases ,Circumflex ,business ,Left main disease ,Artery - Abstract
An 88-year-old man with high-risk NSTEMI was referred for angiography. He was found to have critical left main disease with a 99 % stenosis involving the proximal left anterior descending (LAD) artery and the proximal circumflex (LCX) stenosis consistent with Medina 1,1,1. Due to his co-morbid conditions, he was ultimately turned down for surgical intervention, and referred for PCI. He underwent successful interventional under ECMO support of the left main, proximal LAD and left circumflex coronary arteries, illustrating an example of complex and high-risk PCI involving bifurcation disease.
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- 2017
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13. Complex Case: Rotational Atherectomy in Preparation for TAVR
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Gagan D. Singh, Jason H. Rogers, Reginald I. Low, and Bradley D. Stauber
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medicine.medical_specialty ,business.industry ,Rotational atherectomy ,medicine.disease ,Temporary Pacemaker ,Stenosis ,Heart failure ,Internal medicine ,Conventional PCI ,Cardiology ,Medicine ,In patient ,cardiovascular diseases ,business ,Class III Angina - Abstract
An 84-year-old man with class III angina and heart failure is noted to have critical AV stenosis and severe calcific obstructive disease of the RCA. In preparation for TAVR, PCI of the RCA is undertaken demonstrating rotational atherectomy can be safely performed in patients with critical aortic stenosis.
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- 2017
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14. Complex Case: Saphenous Vein Graft
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Gagan D. Singh, Bradley D. Stauber, Reginald I. Low, and Jeffrey Southard
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medicine.medical_specialty ,surgical procedures, operative ,medicine.anatomical_structure ,Bypass grafting ,business.industry ,Saphenous vein graft ,cardiovascular system ,medicine ,Vein graft ,Rotational atherectomy ,business ,Surgery ,Artery - Abstract
A 61-year-old man with a history of five-vessel coronary artery bypass grafting was found to have symptomatic, severe, and critically obstructive calcific lesions of the vein graft to the RCA. The vein graft underwent rotational atherectomy followed by stenting, demonstrating rotational atherectomy of saphenous vein grafts is possible in appropriately selected patients.
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- 2017
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15. Complex Case: In-Stent Restenosis
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Gagan D. Singh, Bradley D. Stauber, Reginald I. Low, and Jeffrey Southard
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medicine.medical_specialty ,Ejection fraction ,Ischemic cardiomyopathy ,medicine.diagnostic_test ,business.industry ,Rotational atherectomy ,equipment and supplies ,medicine.disease ,Restenosis ,Internal medicine ,Angiography ,medicine ,Cardiology ,cardiovascular diseases ,Myocardial infarction ,Known Coronary Artery Disease ,In stent restenosis ,business - Abstract
A 51-year-old man with a history of ischemic cardiomyopathy (LVEF 25%) and known coronary artery disease with prior RCA stenting is referred for angiography for high-risk non-ST elevation myocardial infarction. He was found to have severe in-stent restenosis, which was treated with rotational atherectomy. This case demonstrates rotational atherectomy as one modality that can be used to treat severe in-stent restenosis.
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- 2017
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16. Straightforward LAD case
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Gagan D. Singh, Bradley D. Stauber, and Reginald I. Low
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medicine.anatomical_structure ,medicine.diagnostic_test ,business.industry ,Angiography ,Anterior wall ,Medicine ,Atypical chest pain ,Perfusion scanning ,Rotational atherectomy ,business ,Nuclear medicine ,Artery - Abstract
An 84-year-old man presents with atypical chest pain and abnormal perfusion scan indicating reversible anterior wall defect. Angiography demonstrated diffuse, calcified lesions in his proximal left anterior descending (LAD) artery of approximately 90%. He was treated with rotational atherectomy, demonstraighting a rather straightforward case in which a heavily calcified vessel can be treated with sequential rotational atherectomy with excellent results.
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- 2017
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17. Predictors and Outcomes of Recurrent Stent Thrombosis
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John S. MacGregor, Jason H. Rogers, Ehrin J. Armstrong, Stephen W. Waldo, Khung-Keong Yeo, Kendrick A. Shunk, Ryan Reeves, Reginald I. Low, Wayland Lim, Shiv Sab, Mitul Patel, Ehtisham Mahmud, and Gagan D. Singh
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Incidence (epidemiology) ,Confidence interval ,Internal medicine ,Angiography ,Conventional PCI ,Cardiology ,Medicine ,Cumulative hazard ,Stent thrombosis ,business ,Cardiology and Cardiovascular Medicine ,TIMI ,Mace - Abstract
Objectives The aim of this study was to determine the incidence, predictors, and outcomes of recurrent stent thrombosis (rST). Background Patients who had an initial stent thrombosis (ST) develop may be at high risk of rST. Methods We analyzed a multicenter California registry of angiographic definite ST at 5 academic hospitals from 2005 to 2013. A detailed review of the angiogram and procedure was performed of patients with and without rST. Results Among 221 patients with a median follow-up of 3.3 years, definite or probable rST developed in 29, including 19 with angiographic definite rST. The cumulative hazard ratio (HR) of definite or probable rST was 16% at 1 year and 24% at 5 years, whereas the cumulative HR of angiographic definite rST was 11% at 1 year and 20% at 5 years. Despite similar angiographic results, patients who had rST develop had significantly greater peak creatine kinase at the time of initial ST (mean, 2,655 mg/dl vs. 1,654 mg/dl; p = 0.05) than those without rST. The 3-year rate of major adverse cardiovascular events was 50% for patients with rST compared with 22% for patients with a single ST (p = 0.01). After multivariable adjustment, independent predictors of definite/probable rST were age (HR: 1.4; 95 confidence interval [CI]: 1.1 to 1.8 per 10 years), bifurcation ST (HR: 4.4; 95% CI: 1.8 to 10.9), and proximal vessel diameter (HR: 1.8; 95% CI: 1.1 to 3.2 per millimeter). Conclusions rST represents an important cause of long-term morbidity and mortality after an initial ST. Bifurcation ST and a larger proximal reference vessel diameter are independently associated with an increased risk of rST.
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- 2014
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18. Transcatheter aortic valve implantation of the direct flow medical aortic valve with minimal or no contrast
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Azeem Latib, Reginald I. Low, John H. Harreld, Antonio Colombo, Francesco Maisano, Federico DeMarco, Giuseppe Bruschi, Charles J. Davidson, Thomas W. Smith, Silvio Klugmann, University of Zurich, and Latib, Azeem
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Male ,Aortic valve ,Cardiac Catheterization ,medicine.medical_specialty ,Aortography ,Percutaneous ,Contrast Media ,Hemodynamics ,Renal function ,610 Medicine & health ,Regurgitation (circulation) ,Coronary Angiography ,Prosthesis Design ,Radiography, Interventional ,Severity of Illness Index ,2705 Cardiology and Cardiovascular Medicine ,chemistry.chemical_compound ,Risk Factors ,Internal medicine ,medicine ,Humans ,Renal Insufficiency, Chronic ,Aged, 80 and over ,Heart Valve Prosthesis Implantation ,Creatinine ,medicine.diagnostic_test ,business.industry ,Acute kidney injury ,Aortic Valve Stenosis ,General Medicine ,Acute Kidney Injury ,medicine.disease ,10020 Clinic for Cardiac Surgery ,Treatment Outcome ,medicine.anatomical_structure ,chemistry ,Aortic Valve ,Heart Valve Prosthesis ,Cardiology ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,business ,Echocardiography, Transesophageal - Abstract
The 18F Direct Flow Medical (DFM) THV has conformable sealing rings, which minimizes aortic regurgitation and permits full hemodynamic assessment of valve performance prior to permanent implantation. During the DISCOVER trial, three patients who were at risk for receiving contrast media, two due to severe CKD and one due to a recent hyperthyroid reaction to contrast, underwent DFM implantation under fluoroscopic and transesophageal guidance without aortography during either positioning or to confirm the final position. Valve positioning was based on the optimal angiographic projection as calculated by the pre-procedural multislice CT scan. Precise optimization of valve position was performed to minimize transvalve gradient and aortic regurgitation. Prior to final implantation, transvalve hemodynamics were assessed invasively and by TEE. The post-procedure mean gradients were 7, 10, 11mm Hg. The final AVA by echo was 1.70, 1.40 and 1.68cm(2). Total aortic regurgitation post-procedure was none or trace in all three patients. Total positioning and assessment of valve performance time was 4, 6, and 12minutes. Contrast was only used to confirm successful percutaneous closure of the femoral access site. The total contrast dose was 5, 8, 12cc. Baseline eGFR and creatinine was 28, 22, 74mL/min/1.73m(2) and 2.35, 2.98, and 1.03mg/dL, respectively. Renal function was unchanged post-procedure: eGFR=25, 35, and 96mL/min/1.73m(2) and creatinine=2.58, 1.99, and 1.03mg/dL, respectively. In conclusion, the DFM THV provides the ability to perform TAVI with minimal or no contrast. The precise and predictable implantation technique can be performed with fluoro and echo guidance.
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- 2014
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19. Angiographic characteristics of definite stent thrombosis: Role of thrombus grade, collaterals, epicardial coronary flow, and myocardial perfusion
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Ehrin J. Armstrong, Shiv Sab, Ehtisham Mahmud, Jason H. Rogers, Mitul Patel, Kendrick A. Shunk, Ryan Reeves, Stephen W. Waldo, Reginald I. Low, and Khung-Keong Yeo
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Stent ,General Medicine ,medicine.disease ,Lower risk ,medicine.anatomical_structure ,Internal medicine ,medicine ,Cardiology ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Radiology ,Stent thrombosis ,Thrombus ,Cardiology and Cardiovascular Medicine ,business ,Perfusion ,TIMI ,Coronary flow ,Artery - Abstract
Objectives To characterize the prevalence of thrombus burden, collateral vessels to the infarct-related artery, epicardial coronary artery flow, and myocardial perfusion in patients with angiographically confirmed definite stent thrombosis (ST), and to define their relationship with associated treatments and outcomes. Background Angiographic characteristics of ST are not well defined. Methods All cases of angiographically determined ST at five academic hospitals from 2005 to 2012 were reviewed. Demographic, procedural, and angiographic characteristics were recorded. In-hospital and 1-year follow-up data were obtained. Results Among 205 cases of angiographic definite ST (60 ± 8 years; 87% male), the majority presented with late/very late ST (69%) and STEMI (66%). High-risk angiographic findings at presentation included thrombus grade 4–5 (87%), absence of collateral vessels (76%), and reduced initial TIMI 3 flow (90%). Final TIMI 3 flow was achieved in 90% of patients and was associated with greater use of aspiration thrombectomy (60% vs. 25%; P = 0.003), glycoprotein IIb/IIIa inhibitors (80% vs. 30%, P
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- 2014
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20. Prospective Multicenter Evaluation of the Direct Flow Medical Transcatheter Aortic Valve
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Silvio Klugmann, Michael Schmoeckel, Karl Eugen Hauptmann, Georg Nickenig, Joachim Schofer, Ivar Friedrich, Azeem Latib, Martyn Thomas, Simon Redwood, Michael J. Mullen, Didier Tchetche, Antonio Colombo, Federico DeMarco, Charles J. Davidson, Christopher Young, Francesco Maisano, Klaudija Bijuklic, Jean Fajadet, Thierry Lefèvre, Neil J. Weissman, Reginald I. Low, Giuseppe Bruschi, Jan Malte Sinning, Michael Lauterbach, John Yap, Eberhard Grube, Schofer, J, Colombo, A, Klugmann, S, Fajadet, J, Demarco, F, Tchetche, D, Maisano, F, Bruschi, G, Latib, A, Bijuklic, K, Weissman, N, Low, R, Thomas, M, Young, C, Redwood, S, Mullen, M, Yap, J, Grube, E, Nickenig, G, Sinning, Jm, Hauptmann, Ke, Friedrich, I, Lauterbach, M, Schmoeckel, M, Davidson, C, and Lefevre, T
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Male ,Cardiac Catheterization ,medicine.medical_specialty ,Transcatheter aortic ,TAVR ,Direct flow ,Cohort Studies ,medicine ,Animals ,Humans ,Prospective Studies ,Aged ,Aged, 80 and over ,Heart Valve Prosthesis Implantation ,High risk patients ,business.industry ,transfemoral ,Aortic Valve Stenosis ,Middle Aged ,medicine.disease ,aortic regurgitation ,Surgery ,Aortic Valve ,Heart Valve Prosthesis ,Aortic valve stenosis ,Cattle ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies - Abstract
ObjectivesThe study sought a prospective multicenter nonrandomized evaluation of the Direct Flow Medical (DFM) system for the treatment of severe aortic stenosis.BackgroundThe DFM transcatheter aortic valve system is a nonmetallic design with a pressurized support structure that allows precise positioning, retrieval, and assessment of valve performance prior to permanent implantation.MethodsOne hundred high surgical risk patients with severe aortic stenosis were evaluated for the primary endpoint. There were 75 patients in the group evaluable for the secondary endpoints and 25 in the pre-specified roll-in training phase. Echocardiographic and angiographic data were evaluated by an independent core laboratory and adverse events adjudicated by clinical event committee and classified according to Valve Academic Research Consortium (VARC) criteria.ResultsThere was 99% freedom from all cause mortality at 30 days (primary endpoint). VARC criteria defined 30 day combined freedom from patient safety event rate was 91% and overall device success was 93%. The post-implantation echocardiography results demonstrated mild or no aortic regurgitation in 99% (73 of 74) with a mean gradient of 12.6 ± 7.1 mm Hg (n = 72) and effective orifice area of 1.50 ± 0.56 cm2 and New York Heart Association functional class was I or II in 92% of cases.ConclusionsThe present study demonstrates the safety and efficacy of the DFM system in surgical high risk patients with severe aortic stenosis and complex anatomy aortic regurgitation was less than moderate in 99% of patients.
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- 2014
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21. PCI after TAVR—What’s the Price of Reentry?
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Garrett B. Wong, Jeffrey Southard, Reginald I. Low, and Jeong W. Choi
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medicine.medical_specialty ,business.industry ,Internal medicine ,Conventional PCI ,medicine ,Cardiology ,Reentry ,Cardiology and Cardiovascular Medicine ,business - Published
- 2018
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22. Delayed Left Main Narrowing From the Native Left Aortic Valve Leaflet After Transcatheter Aortic Valve Replacement With the Lotus Valve
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Benjamin Stripe, Reginald I. Low, Matthew S. Glassy, and Jeffrey Southard
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Aortic valve ,medicine.medical_specialty ,Transcatheter aortic ,business.industry ,medicine.medical_treatment ,Percutaneous coronary intervention ,medicine.disease ,Balloon ,Surgery ,medicine.anatomical_structure ,Valve replacement ,Angioplasty ,Aortic valve stenosis ,cardiovascular system ,medicine ,Cardiology and Cardiovascular Medicine ,Complication ,business - Abstract
An 89-year-old woman with severe symptomatic aortic valve stenosis and poor surgical candidacy underwent transcatheter aortic valve replacement (TAVR) with a 23-mm Lotus valve (Boston Scientific, Marlborough, Massachusetts). Preoperative computed tomography demonstrated aortic sinuses and coronary
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- 2018
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23. Complete Transcatheter Treatment of Degenerated Bioprosthetic Mitral Regurgitation
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Walter D. Boyd, Reginald I. Low, Jason H. Rogers, Jeffrey Southard, Garrett B. Wong, Femi Philip, Thomas W. Smith, and Gagan D. Singh
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medicine.medical_specialty ,Mitral regurgitation ,business.industry ,medicine.medical_treatment ,Closure (topology) ,Surgery ,medicine.anatomical_structure ,Valve replacement ,Internal medicine ,Mitral valve ,medicine ,Cardiology ,Paravalvular leak ,Cardiology and Cardiovascular Medicine ,business - Abstract
A 67-year-old woman (frail, body mass index of 18, forced expiratory volume1 of 0.86, Society of Thoracic Surgeons score of 12%) was referred for transcatheter correction of a severely degenerated bioprosthetic (29-mm Edwards Perimount Bovine Pericardial, Edwards Lifesciences, Irvine, California)
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- 2015
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24. Noncentral Mitral Regurgitation
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Reginald I. Low and Jason H. Rogers
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medicine.medical_specialty ,Mitral regurgitation ,business.industry ,MitraClip ,urologic and male genital diseases ,Surgery ,Increased risk ,Internal medicine ,medicine ,Cardiology ,High surgical risk ,In patient ,Cardiology and Cardiovascular Medicine ,business - Abstract
MitraClip therapy (Abbott, Abbott Park, Illinois) is an important treatment for correcting clinically significant mitral regurgitation (MR) in patients at increased risk for surgery. This therapy can now be offered to many patients with comorbidities who are at high surgical risk and would not
- Published
- 2013
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25. Procedural success and long-term outcomes of aspiration thrombectomy for the treatment of stent thrombosis
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Khung-Keong Yeo, John S. MacGregor, Jason H. Rogers, Stephen W. Waldo, Mitul Patel, Ehtisham Mahmud, Kendrick A. Shunk, Reginald I. Low, Ehrin J. Armstrong, and Ryan Reeves
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medicine.medical_specialty ,Percutaneous ,business.industry ,medicine.medical_treatment ,Percutaneous coronary intervention ,General Medicine ,medicine.disease ,Revascularization ,Clinical trial ,Internal medicine ,Cohort ,Cardiology ,Medicine ,Radiology, Nuclear Medicine and imaging ,Myocardial infarction ,Cardiology and Cardiovascular Medicine ,business ,Stroke ,TIMI - Abstract
Background Stent thrombosis (ST) is associated with a significant burden of coronary thrombus and potential microvascular obstruction. Aspiration thrombectomy may decrease the extent of microvascular obstruction in patients with acute myocardial infarction but its role in the treatment of ST is uncertain. The present study sought to evaluate the association between aspiration thrombectomy, procedural success and long-term outcomes among patients presenting with ST. Methods In a multicenter cohort of patients with definite ST, procedural success, long-term mortality, and major adverse cardiovascular events (death, stroke, re-infarction, revascularization) were ascertained. Propensity weighting was used to determine the association between aspiration thrombectomy and long-term outcomes. Results A total of 205 patients with ST were identified. Among these, 115 (56%) patients underwent adjunctive aspiration thrombectomy during percutaneous coronary intervention. Patients undergoing aspiration thrombectomy were more likely to present with ST-elevation myocardial infarction (75% vs. 52%, P
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- 2013
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26. 4-Year Results of a Randomized Controlled Trial of Percutaneous Repair Versus Surgery for Mitral Regurgitation
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Tanvir Bajwa, Andrew Wang, Wesley R. Pedersen, Joseph M. Massaro, William A. Gray, John M. Lasala, Howard C. Herrmann, Laura Mauri, James B. Hermiller, Patricia Apruzzese, Ted Feldman, Donald D. Glower, Reginald I. Low, Paul A. Grayburn, Elyse Foster, and Everest Investigators
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medicine.medical_specialty ,Percutaneous ,medicine.medical_treatment ,Percutaneous Coronary Intervention ,Mitral valve ,medicine ,Humans ,percutaneous valve therapy ,Prospective Studies ,Mitral regurgitation ,mitral repair ,business.industry ,MitraClip ,valvular heart disease ,Mitral Valve Insufficiency ,Percutaneous coronary intervention ,medicine.disease ,Surgery ,Survival Rate ,Treatment Outcome ,medicine.anatomical_structure ,mitral regurgitation ,Cardiology and Cardiovascular Medicine ,business ,Mitral valve regurgitation ,Percutaneous Mitral Valve Repair ,Follow-Up Studies - Abstract
ObjectivesThis study sought to evaluate 4-year outcomes of percutaneous repair versus surgery for mitral regurgitation.BackgroundTranscatheter therapies are being developed to treat valvular heart disease. In the EVEREST (Endovascular Valve Edge-to-Edge Repair Study) II trial, treatment of mitral valve regurgitation (MR) with a novel percutaneous device was compared with surgery and showed superior safety, but less reduction in MR at 1 year overall. We report the 4-year outcomes from the EVEREST II trial.MethodsPatients with grade 3+ or 4+ MR were randomly assigned to percutaneous repair with the MitraClip (Abbott, Menlo Park, California) device or conventional mitral valve surgery in a 2:1 ratio (184:95). Patients prospectively consented to 5 years of follow-up.ResultsAt 4 years, the rate of the composite endpoint of freedom from death, surgery, or 3+ or 4+ MR in the intention-to-treat population was 39.8% versus 53.4% in the percutaneous repair group and surgical groups, respectively (p = 0.070). Rates of death were 17.4% versus 17.8% (p = 0.914), and 3+ or 4+ MR was present in 21.7% versus 24.7% (p = 0.745) at 4 years of follow-up, respectively. Surgery for mitral valve dysfunction, however, occurred in 20.4% versus 2.2% (p < 0.001) at 1 year and 24.8% versus 5.5% (p < 0.001) at 4 years.ConclusionsPatients treated with percutaneous repair of the mitral valve more commonly required surgery to treat residual MR; however, after the first year of follow-up, there were few surgeries required after either percutaneous or surgical treatment and no difference in the prevalence of moderate-severe and severe MR or mortality at 4 years. (Endovascular Valve Edge-to-Edge Repair Study [EVEREST II]; NCT00209274)
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- 2013
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27. Transradial and transfemoral coronary angiography and interventions: 1-Year outcomes after initiating the transradial approach in a cardiology training program
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Garrett B. Wong, Jeffrey Southard, Khung Keong Yeo, Usman Javed, Reginald I. Low, Ehrin J. Armstrong, Jason H. Rogers, John R. Laird, Christopher R. Balwanz, and Gagan D. Singh
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Male ,Coronary angiography ,medicine.medical_specialty ,medicine.medical_treatment ,Psychological intervention ,Coronary Angiography ,Percutaneous Coronary Intervention ,Internal medicine ,Humans ,Medicine ,Fluoroscopy ,Myocardial infarction ,Aged ,medicine.diagnostic_test ,business.industry ,Percutaneous coronary intervention ,Middle Aged ,medicine.disease ,Femoral Artery ,Concomitant ,Radial Artery ,Conventional PCI ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business ,Training program - Abstract
Background Limited data are available regarding the safety and feasibility of initiating transradial (TR) diagnostic coronary angiography (CA) and percutaneous coronary intervention (PCI) in cardiology fellowship programs. Methods From July 2010 to June 2011, University of California, Davis Medical Center, adopted the TR approach with supervised cardiology fellows as the primary operators. Procedural variables and clinical outcomes of TR and transfemoral (TF) procedures were compared. To minimize confounding variables, ST-elevation myocardial infarction, bypass graft interventions, chronic total occlusions, and procedures with concomitant right heart catheterizations were excluded. To reflect the learning curve of the TR approach, this experience was assessed in 2 sequential 6-month periods. Results A total of 402 diagnostic CAs and 255 PCIs were included. Transradial access was used in 141 (35%) of the CAs and in 72 (28%) of PCIs. Within the TR-CA and TF-CA (n = 261) groups, there was no difference between fluoroscopy (10.4 ± 6.0 vs 11.0 ± 8.9, P = .63) or procedure (31.8 ± 11.5 vs 33.2 ± 13.8, P = .55) time throughout the academic year with a significant trend toward lower contrast use (128 ± 52 vs 110 vs 50, P = .04) by the second half. In addition, during the second half of the academic year, the TR-CA showed significantly higher fluoroscopy (11.0 ± 8.9 vs 6.7 ± 6.8, P = .001) and procedure (33.2 ± 13.8 vs 27.2 ± 11.6, P = .0015) times when compared with TF-CA. Transfemoral PCI (n = 183) and TR-PCI showed no significant difference between all fluoroscopy and procedure time and contrast use when comparing the 2 halves of the academic year. When comparing TF with TR within each academic half year, there was no difference within the PCI group. Vascular complications were less with the TR approach. Overall procedural success rates were high, and there were low rates of crossover and periprocedural complications in both the TR and the TF groups. Conclusion A TR approach is safe for CA and PCI when performed by supervised operators in training. Although the learning curve for trainees appears slower for TR-CA compared with TF-CA, cardiology fellowship training programs should be encouraged to adopt TR procedures as part of their curriculum.
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- 2013
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28. Angiographically confirmed stent thrombosis in contemporary practice: Insights from intravascular ultrasound
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Usman Javed, Reginald I. Low, Mitul Patel, Kendrick A. Shunk, John S. MacGregor, Ehrin J. Armstrong, Jason H. Rogers, Khung Keong Yeo, Andrew T. Kwa, and Ehtisham Mahmud
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Stent ,General Medicine ,equipment and supplies ,surgical procedures, operative ,Internal medicine ,Intravascular ultrasound ,medicine ,Cardiology ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Radiology ,Stent thrombosis ,Cardiology and Cardiovascular Medicine ,business - Abstract
Objective: We hypothesized that patients presenting with stent thrombosis (ST) have a high prevalence of stent underexpansion and malapposition when assessed by intravascular ultrasound (IVUS). Background: IVUS can provide mechanistic insight into mechanical factors, including stent underexpansion, malapposition, and fracture that may predispose to ST. Methods: All consecutive cases of angiographically confirmed ST from a multicenter registry (from 2005 to 2010) were reviewed. All IVUS images were reviewed off-line for the presence of stent underexpansion, malapposition, and fracture. Kaplan–Meier analysis was used to determine whether use of IVUS at the time of ST was associated with long-term mortality and major adverse cardiovascular events. Results: IVUS was performed in 32 of 173 subjects with ST (18%). Stent underexpansion was present in 82% of cases and in all cases of early ST, with a mean stent expansion of 0.7 ± 0.23 by MUSIC criteria. Stent malapposition was most frequently observed in very late ST (40%). In-hospital mortality was similar between subjects who had IVUS performed at the time of ST when compared with the non-IVUS group (3.2% vs. 4.3%, P = 0.8). Subjects who had IVUS performed at the time of ST had lower rates of mortality (HR 0.4, 95% CI 0.1-1.6, P =0.2) and major adverse cardiovascular events (HR 0.5, 95% CI 0.2–1.4, P =0.2) at follow-up, but these values were not statistically significant. Conclusions: There is a high prevalence of stent underexpansion in early ST, while the prevalence of malapposition is higher in very late ST. Use of IVUS during treatment for ST may identify mechanisms underlying the development of ST. © 2012 Wiley Periodicals, Inc.
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- 2012
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29. Prevalence and echocardiographic features of iatrogenic atrial septal defect after catheter-based mitral valve repair with the mitraclip system
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William J. Bommer, Peter S. Fail, Jason H. Rogers, Scott Lim, Patrick M. Mcginty, Reginald I. Low, and Thomas W. Smith
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Cardiac Catheterization ,medicine.medical_specialty ,Catheters ,Time Factors ,medicine.medical_treatment ,Iatrogenic Disease ,Echocardiography, Three-Dimensional ,Hemodynamics ,law.invention ,Randomized controlled trial ,Predictive Value of Tests ,Risk Factors ,Left atrial ,law ,Internal medicine ,Prevalence ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Mitral valve repair ,Mitral regurgitation ,Atrial Septum ,business.industry ,MitraClip ,Mitral Valve Insufficiency ,General Medicine ,Echocardiography, Doppler ,Echocardiography, Doppler, Color ,Surgery ,Catheter ,Heart Injuries ,Echocardiography ,Predictive value of tests ,Cardiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Objectives: Review the prevalence, echocardiographic features and potential predictors of iatrogenic ASD (iASD) created with the MitraClip guiding catheter. Background: Catheter-based repair of mitral regurgitation (MR) with the MitraClip device (Abbott Vascular, Menlo Park, CA), is performed through a 22-French transseptal guiding catheter. The echocardiographic prevalence of iASDs after the MitraClip procedure has not been reported. Methods: Thirty subjects undergoing MitraClip repair during the roll-in phase of the EVEREST II randomized trial who had baseline, 30 day, 6 and 12 month transthoracic echocardiograms (TTEs) available for review were included. Patients who underwent surgery for MR within the first 12 months were excluded. Residual iASD size, right ventricular (RV) size, left atrial (LA) volume, and tricuspid/MR grade were quantified. Results: iASDs were found at 12 months in 8 patients (27%) with a mean diameter of 6.6 ± 3.1 mm. Subjects with iASD at 12 months had more residual MR, increased TR and a trend toward larger LA volumes than non-iASD patients. 83% of non-ASD patients were free from MR > 2+ at 12 mos. vs. 38% of those with iASD (p=0.016). There were no other significant associations between clinical and echocardiographic variables and the persistence of iASD. Conclusions: After MitraClip repair, persistent iASDs occur at a rate comparable to reports after other transseptal interventional procedures and do not appear hemodynamically significant. Patients with persistent iASDs had less MR reduction at 12-months and a trend toward larger LA volumes, suggesting that increased LA pressure may be a mechanism for persistent iASD. © 2012 Wiley Periodicals, Inc.
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- 2012
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30. Angiographic Stent Thrombosis at Coronary Bifurcations
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John S. MacGregor, Khung Keong Yeo, Mitul Patel, Kendrick A. Shunk, Reginald I. Low, Ehrin J. Armstrong, Ehtisham Mahmud, Jason H. Rogers, and Usman Javed
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Stent ,medicine.disease ,Coronary artery disease ,Main vessel ,Internal medicine ,Side branch ,Conventional PCI ,medicine ,Cardiology ,cardiovascular diseases ,Radiology ,Stent thrombosis ,Thrombus ,business ,Cardiology and Cardiovascular Medicine ,Mace - Abstract
Objectives This study sought to describe the presentation, management, and outcomes of patients presenting with angiographic definite stent thrombosis (ST) at coronary bifurcations. Background The development of drug-eluting stents has made it increasingly feasible to treat bifurcation lesions percutaneously. However, ST at coronary bifurcations may be associated with greater mortality than ST elsewhere. Methods We analyzed a multicenter California registry comprising all cases of angiographic definite ST at 5 academic hospitals from 2005 to 2010. Stenting was defined as occurring at a bifurcation if the main vessel stent crossed a side branch ≥2.0 mm in diameter (provisional single-stent approach), or if there was a prior 2-stent bifurcation approach. Results Among 173 cases of angiographic definite ST, we identified 20 cases of ST at coronary bifurcations. Nine of 20 bifurcation ST (45%) occurred with a stent present in both the parent and branch vessel. Eight cases had thrombus present in both the parent and side branch vessels. In-hospital mortality was much higher for subjects with bifurcation ST than ST at a nonbifurcation site (20% vs. 2%, p Conclusions ST at coronary bifurcations is associated with a higher in-hospital and long-term mortality than ST at nonbifurcation lesions. (Stent Thrombus in Acute Coronary Syndromes; NCT00931502)
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- 2012
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31. SAPIEN S3 Leaflet Malfunction With Severe Intravalvular Aortic Insufficiency Immediately Post-Deployment
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Paul A. Perry, Thomas W. Smith, Reginald I. Low, Garrett B. Wong, Walter D. Boyd, Jeffrey Southard, and Gagan D. Singh
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Male ,medicine.medical_specialty ,Transcatheter aortic ,medicine.medical_treatment ,Aortic Valve Insufficiency ,Computed tomography ,030204 cardiovascular system & hematology ,Severity of Illness Index ,Transcatheter Aortic Valve Replacement ,03 medical and health sciences ,0302 clinical medicine ,Valve replacement ,Internal medicine ,Humans ,Medicine ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Aortic Valve Stenosis ,medicine.disease ,Echocardiography, Doppler, Color ,Prosthesis Failure ,Surgery ,Aortic Valve ,Heart Valve Prosthesis ,030220 oncology & carcinogenesis ,Aortic valve stenosis ,cardiovascular system ,Cardiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
An 85-year-old male (Society of Thoracic Surgeons score 4%) was referred for transcatheter aortic valve replacement for severe aortic valve stenosis (mean gradient, 43 mm Hg). Noninvasive computed tomography sizing demonstrated annular dimensions of 32.0 × 22.6 mm, and an area of 5.65 cm2.
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- 2017
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32. Internal pudendal artery stenoses and erectile dysfunction: Correlation with angiographic coronary artery disease
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John R. Laird, Dwayne S. Yamasaki, Daniel P. Link, Houshang Karimi, Jason H. Rogers, Reginald I. Low, Mark J. Dolan, Javid Javidan, and John Kao
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Population ,Arterial Occlusive Diseases ,Pilot Projects ,Constriction, Pathologic ,Coronary Artery Disease ,Coronary Angiography ,Severity of Illness Index ,California ,Coronary artery disease ,Erectile Dysfunction ,Predictive Value of Tests ,Surveys and Questionnaires ,Internal medicine ,medicine.artery ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Treatment Failure ,Internal pudendal artery ,skin and connective tissue diseases ,education ,Macrovascular disease ,Cardiac catheterization ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,General Medicine ,Middle Aged ,Phosphodiesterase 5 Inhibitors ,bacterial infections and mycoses ,medicine.disease ,respiratory tract diseases ,Coronary arteries ,Stenosis ,medicine.anatomical_structure ,Angiography ,Cardiology ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Penis - Abstract
Objectives: To describe the angiographic characteristics of pelvic arterial disease in patients with erectile dysfunction (ED) nonresponsive to phosphodiesterase-5 inhibitors (PDE5i) and suspected coronary artery disease (CAD). Background: ED and CAD share common risk factors which can result in endothelial dysfunction, atherosclerosis and flow-limiting stenoses in the coronary and internal pudendal arteries. Methods: Ten patients undergoing cardiac catheterization with ED and a history of unsatisfactory response to a PDE5i were studied. ED severity was quantified using the International Index of ED scoring system. We performed angiography and quantitative vessel analysis of the coronary arteries, bilateral common and internal iliac arteries, and internal pudendal arteries (IPAs). Results: In this pilot observational study, we found a high correlation between the presence of angiographic CAD and IPA disease. The reference IPA diameters at the point of maximal stenosis were 2.7 ± 0.4 mm (right IPA) and 2.7 ± 0.5 mm (left IPA). In the nine patients with IPA disease, the average stenosis severity was 55 ± 31% (right) and 66% ± 25% (left), and average lesion length was 12.4 ± 5.2 mm (right) and 10.0 ± 3.5 mm (left). Four patients had unilateral IPA total occlusions, three of whom had moderate contralateral disease. The majority of IPA stenoses occurred in the mid to distal IPA and appears amenable to percutaneous revascularization. Conclusions: This represents the first angiographic report of CAD correlated with IPA disease in patients with ED. Further investigation is required to determine whether the development of macrovascular disease in the IPA causes ED and whether endovascular treatment is safe and effective in this population. © 2010 Wiley-Liss, Inc.
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- 2010
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33. INTRAPROCEDURAL DIRECT LEFT ATRIAL AND WEDGE PRESSURE CORRELATION DURING TRANSCATHETER MITRAL VALVE REPAIR: RESULTS FROM A SINGLE CENTER REGISTRY
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Neha Maheshwari Mantri, Maia Eng, Jason H. Rogers, Lily Chen, Reginald I. Low, Dali Fan, William Wung, Thomas W. Smith, Gagan D. Singh, and Douglas P. Boyd
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medicine.medical_specialty ,Left atrial ,business.industry ,Internal medicine ,medicine ,Cardiology ,Transcatheter mitral valve repair ,Cardiology and Cardiovascular Medicine ,Pulmonary wedge pressure ,Single Center ,business - Published
- 2018
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34. Percutaneous Mitral Repair With the MitraClip System
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Peter S. Fail, William A. Gray, Richard W. Smalling, Saibal Kar, Ted Feldman, Howard C. Herrmann, Patrick L. Whitlow, Everest Investigators, James B. Hermiller, Elyse Foster, Reginald I. Low, Donald D. Glower, Scott Lim, and Michael Rinaldi
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Mitral valve repair ,medicine.medical_specialty ,Mitral regurgitation ,business.industry ,medicine.medical_treatment ,MitraClip ,Surgery ,medicine ,Embolization ,Cardiology and Cardiovascular Medicine ,Prospective cohort study ,business ,Complication ,Percutaneous Mitral Valve Repair ,Cardiac catheterization - Abstract
Objectives We undertook a prospective multicenter single-arm study to evaluate the feasibility, safety, and efficacy of the MitraClip system (Evalve Inc., Menlo Park, California). Background Mitral valve repair for mitral regurgitation (MR) has been performed by the use of a surgically created double orifice. Percutaneous repair based on this surgical approach has been developed by use of the Evalve MitraClip device to secure the mitral leaflets. Methods Patients with 3 to 4+ MR were selected in accordance with the American Heart Association/American College of Cardiology guidelines for intervention and a core echocardiographic laboratory. Results A total of 107 patients were treated. Ten (9%) had a major adverse event, including 1 nonprocedural death. Freedom from clip embolization was 100%. Partial clip detachment occurred in 10 (9%) patients. Overall, 79 of 107 (74%) patients achieved acute procedural success, and 51 (64%) were discharged with MR of ≤1+. Thirty-two patients (30%) had mitral valve surgery during the 3.2 years after clip procedures. When repair was planned, 84% (21 of 25) were successful. Thus, surgical options were preserved. A total of 50 of 76 (66%) successfully treated patients were free from death, mitral valve surgery, or MR >2+ at 12 months (primary efficacy end point). Kaplan-Meier freedom from death was 95.9%, 94.0%, and 90.1%, and Kaplan-Meier freedom from surgery was 88.5%, 83.2%, and 76.3% at 1, 2, and 3 years, respectively. The 23 patients with functional MR had similar acute results and durability. Conclusions Percutaneous repair with the MitraClip system can be accomplished with low rates of morbidity and mortality and with acute MR reduction to
- Published
- 2009
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35. Long-term safety and durability of percutaneous septal sinus shortening (The PS3System™) in an ovine model
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Fermin O. Tio, Jason H. Rogers, Elizabeth A. Taylor, David A. Rahdert, Gary R. Caputo, Reginald I. Low, Patricia A. Takeda, and Igor F. Palacios
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Cardiac Catheterization ,medicine.medical_specialty ,Time Factors ,Percutaneous ,Perforation (oil well) ,Coronary Angiography ,Intracardiac injection ,Great cardiac vein ,Internal medicine ,Materials Testing ,Heart Septum ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Thrombus ,Systole ,Ultrasonography, Interventional ,Sheep ,business.industry ,Suture Techniques ,Equipment Design ,General Medicine ,medicine.disease ,Thrombosis ,Catheter ,Models, Animal ,Cardiology ,Mitral Valve ,Tomography, X-Ray Computed ,Cardiology and Cardiovascular Medicine ,business - Abstract
Objectives: Chronic implants of the PS3™ system were conducted in an ovine model to assess durability and safety at up to 1 year follow-up. Background: The long-term durability and safety of emerging percutaneous devices for functional mitral regurgitation remain largely unknown. Methods: The PS3 system (consisting of interatrial septal and great cardiac vein devices connected by an adjustable suture bridge) was placed in eight healthy adult sheep. The mitral annular septal-lateral dimension in systole (SLS) was acutely reduced by 15–20%. Animals were sacrificed at up to 12 months postimplant and characterized by intracardiac echocardiography, cardiac computed tomography (CT), and histopathology. In vivo forces exerted on the PS3 bridge were measured by means of a novel load cell catheter. Results: At 3, 6, and 12 months after implantation, intracardiac echocardiographic and CT showed the PS3 systems to be intact without erosion and with overall sustained reductions in the SLS. Histopathologic assessment revealed each component correctly deployed in its respective target site without evidence of erosion, thrombus, or device fracture. The SLS was 26.5 ± 1.7 mm preimplant, 22.0 ± 1.4 mm post-PS3 (17.0% reduction), and 22.0 ± 2.1 mm at latest follow-up. Mean forces exerted on the bridge in vivo ranged from 1.16 N to 1.87 N. Conclusions: The PS3 System demonstrated excellent biocompatibility without evidence of erosion, thrombosis, or perforation at up to one-year follow-up in this chronic healthy ovine model. Forces exerted in the PS3 system were relatively modest and should contribute to the durability of the device. © 2009 Wiley-Liss, Inc.
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- 2009
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36. High-frequency vibration for the recanalization of guidewire refractory chronic total coronary occlusions
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Mark Reisman, Greg Braden, Klaus Tiroch, Gregg W. Stone, Todd Caulfield, Alexandra Almonacid, Ronald P. Caputo, Louis Cannon, Richard R. Heuser, Jeffrey J. Popma, and Reginald I. Low
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Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Perforation (oil well) ,Coronary Angiography ,Balloon ,Vibration ,Coronary artery disease ,Angina ,Surveys and Questionnaires ,Angioplasty ,Occlusion ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Treatment Failure ,Myocardial infarction ,Angioplasty, Balloon, Coronary ,Aged ,business.industry ,Coronary Stenosis ,Equipment Design ,General Medicine ,Middle Aged ,medicine.disease ,United States ,Surgery ,Catheter ,Coronary Occlusion ,Fluoroscopy ,Chronic Disease ,Quality of Life ,Feasibility Studies ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background: Recanalization of coronary chronic total occlusions (CTOs) remains a clinical challenge, particularly when standard guidewire attempts fail. Objectives: We sought to determine the safety and efficacy of a novel method that used high-frequency (20 kHz) vibration to fragment occlusive fibrous tissue and facilitate guidewire crossing into the distal vessel. Methods: A total of 125 patients with CTO, who failed at attempts of conventional guidewire recanalization after more than 5 min of fluoroscopy time, were enrolled in the study. The primary efficacy endpoint was the advancement of the CROSSER™ catheter through the occlusion and attainment of coronary guidewire positioning in the distal coronary lumen. The primary safety endpoint was the occurrence of death, myocardial infarction, clinical perforation, or target vessel revascularization within the first 30 days. Results: The average fluoroscopy time while delivering the CROSSER catheter was 12.4 min. CROSSER-assisted guidewire recanalization was achieved in 76 (60.8%) procedures and a final diameter stenosis
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- 2008
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37. Retrograde Transarterial Implantation of a Nonmetallic Aortic Valve Prosthesis in High–Surgical-Risk Patients With Severe Aortic Stenosis
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Olaf Franzen, Hendrik Treede, Michael Schlüter, Steven F. Bolling, Thomas Meinertz, Andrea Pascotto, Reginald I. Low, Hermann Reichenspurner, Joachim Schofer, and Thilo Tübler
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Male ,medicine.medical_specialty ,Percutaneous ,medicine.medical_treatment ,Hemodynamics ,Prosthesis ,Catheterization ,Risk Factors ,Internal medicine ,medicine.artery ,medicine ,Humans ,Stroke ,Aged ,Aged, 80 and over ,Heart Valve Prosthesis Implantation ,Aorta ,Percutaneous aortic valve replacement ,business.industry ,Aortic Valve Stenosis ,medicine.disease ,Survival Analysis ,Surgery ,Stenosis ,Treatment Outcome ,Aortic Valve ,Heart Valve Prosthesis ,Concomitant ,Disease Progression ,Cardiology ,Feasibility Studies ,Female ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies - Abstract
Background— To assess the feasibility and safety of retrograde transarterial implantation of a novel nonmetallic aortic valve prosthesis (Direct Flow Medical Inc, Santa Rosa, Calif), a prospective single-center study was performed in patients with severe aortic stenosis at high risk for open-heart surgery. Methods and Results— Fifteen patients (intention-to-treat cohort) with an aortic valve area ≤0.8 cm 2 , a ≥35-mm Hg mean transvalvular pressure gradient, and a logistic EuroSCORE ≥20% were enrolled. Percutaneous aortic valve replacement was performed with the patient under general anesthesia. Hemodynamic parameters were assessed before and after implantation by transesophageal echocardiography. Clinical follow-up and transthoracic echocardiographic assessment were obtained at 30 days. Procedural success was achieved in 12 patients (80%). Surgical conversion became necessary at day 2 in 1 patient; 11 patients (73%) were discharged with a permanent implant. In these patients, implantation resulted acutely in a significant increase in aortic valve area (median, 1.64 [interquartile range, 1.27 to 1.74] versus 0.60 [0.46 to 0.69] cm 2 ; P =0.0033) and a concomitant reduction in the mean pressure gradient (14.0 [13.2 to 16.5] versus 54.0 [43.2 to 59.8] mm Hg; P =0.0033). At 30 days, 1 cardiac death (6.7%; 95% CI, 0.2% to 32.0%) and 1 major stroke were observed. The 10 surviving patients with a permanent implant showed marked hemodynamic and clinical improvement at this time point. Conclusions— In this small series of patients, percutaneous implantation of the Direct Flow Medical aortic valve prosthesis in high–surgical-risk patients was feasible and associated with a reasonably low safety profile.
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- 2008
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38. Direct Flow Medical percutaneous aortic valve: proof of concept
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Steven F. Bolling, Adrian Ebner, Reginald I. Low, and Khung Keong Yeo
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Aortic valve ,medicine.medical_specialty ,Percutaneous ,business.industry ,medicine.disease ,Direct flow ,Surgery ,Clinical trial ,Stenosis ,medicine.anatomical_structure ,Aortic valve replacement ,Internal medicine ,Severity of illness ,medicine ,Cardiology ,Heart valve ,Cardiology and Cardiovascular Medicine ,business - Abstract
AIMS This paper reports the technical feasibility of using the Direct Flow Medical percutaneous aortic valve (PAV) to treat patients with severe aortic stenosis (AS). METHODS AND RESULTS Eight patients with critical AS underwent temporary implantation of the PAV. Two patients received open surgical implantation of the device while six patients underwent percutaneous implantation. The mean age of these eight patients was 58.1 years, mean pre-procedural aortic valve area was
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- 2008
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39. Percutaneous aortic valve implantation utilising a novel tissue valve: preclinical experience
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Jason H. Rogers, Nicolo Piazza, Peter C. Block, Steven F. Bolling, Vasilis Babaliaros, Patricia A. Takeda, and Reginald I. Low
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Heart Valve Prosthesis Implantation ,Prosthetic valve ,Aortic valve ,medicine.medical_specialty ,Percutaneous ,business.industry ,Prosthesis Design ,Asymptomatic ,Valvula aortica ,Catheterization ,Surgery ,medicine.anatomical_structure ,Cadaver ,Aortic Valve ,Heart Valve Prosthesis ,medicine ,Animals ,Humans ,Prosthesis design ,Cattle ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Published
- 2008
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40. Aortic Stenosis: Assessment of the Patient at Risk
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Khung Keong Yeo and Reginald I. Low
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Cardiac Catheterization ,medicine.medical_specialty ,medicine.medical_treatment ,Population ,Doppler echocardiography ,Risk Assessment ,Syncope ,Angina Pectoris ,Angina ,Aortic valve replacement ,Internal medicine ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Cardiac Output ,education ,Cardiac catheterization ,Heart Failure ,Heart Valve Prosthesis Implantation ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Hemodynamics ,Aortic Valve Stenosis ,Prognosis ,medicine.disease ,Echocardiography, Doppler ,Surgery ,Stenosis ,Aortic valve stenosis ,Disease Progression ,Exercise Test ,cardiovascular system ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,Risk assessment - Abstract
The true incidence of aortic stenosis among the general population is unknown but aortic sclerosis, its precursor, has been estimated to affect about 25% of people over age 65, while an estimated 3% of the population over age 75 have severe aortic stenosis. Severe aortic stenosis, when accompanied by symptoms of angina, syncope, or heart failure, is associated with high mortality rates. Two-dimensional and Doppler echocardiography are cornerstone tools for the evaluation and monitoring of aortic stenosis. Echocardiography helps identify the patient at risk of death and guide timing of aortic valve replacement. Other important diagnostic tools include cardiac catheterization, treadmill stress testing, and dobutamine stress echocardiography, although their use is limited to specific patient populations. Aortic valve replacement carries a significant operative risk of approximately 4.0%. However, risk of operative mortality varies according to comorbidities and disease presentation. There are many risk models that guide estimation of the risk of operative mortality. Understanding operative risk is important in patient care and the selection of patients for aortic valve replacement.
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- 2007
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41. Accuracy and procedural characteristics of standard needle compared with radiofrequency needle transseptal puncture for structural heart interventions
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Gaurav, Sharma, Gagan D, Singh, Thomas W, Smith, Dali, Fan, Reginald I, Low, and Jason H, Rogers
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Aged, 80 and over ,Male ,Cardiac Catheterization ,Equipment Design ,Punctures ,Middle Aged ,Needles ,Catheter Ablation ,Heart Septum ,Humans ,Female ,Echocardiography, Transesophageal ,Aged ,Retrospective Studies - Abstract
Our objectives were to assess for differences between standard and radiofrequency (RF) needle in procedural times, success, and spatial accuracy.Targeted transseptal (TS) puncture is essential for structural heart interventions. Spatial accuracy of standard versus RF needle has not been reported.Consecutive patients undergoing structural heart interventions requiring TS puncture were studied retrospectively. A standard needle was alternated with a RF needle. Procedural success and times were recorded. Measurements based on intraprocedural transesophageal echocardiograms of the intended versus final TS crossing site were obtained. Pre-puncture and maximal tenting of the septum were also recorded.Twenty-five patients underwent standard needle and 27 RF TS access. All RF needle attempts to cross were successful without an assistance wire. Three standard needle patients required assisted crossing. After failed TS access, two patients had successful RF TS access. TS procedural times significantly favored the RF needle for time from septum to puncture (P = 0.02). Both standard and RF access yielded accurate crossing with no significant differences between the intended and actual crossing site. Maximal tenting was significantly less with the RF needle (P = 0.004). There were no major complications.In the hands of an experienced operator, there were no major clinically significant differences between the standard and RF needle approaches. However, procedural unassisted crossing success was higher with the RF needle approach as compared to standard needle. Procedural times and degree of septum tenting favored the RF over standard needle. Accuracy was similar with both approaches. RF was a successful strategy when standard needle failed. There were no major complications with either TS puncture strategy. © 2016 Wiley Periodicals, Inc.
- Published
- 2015
42. Complete Transcatheter Treatment of Degenerated Bioprosthetic Mitral Regurgitation: Transapical Paravalvular Leak Closure Followed by Transseptal Mitral Valve-in-Valve Replacement
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Gagan D, Singh, Thomas W, Smith, Walter D, Boyd, Jeffrey A, Southard, Garrett B, Wong, Femi, Philip, Reginald I, Low, and Jason H, Rogers
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Bioprosthesis ,Heart Valve Prosthesis Implantation ,Reoperation ,Cardiac Catheterization ,Mitral Valve Insufficiency ,Severity of Illness Index ,Prosthesis Failure ,Heart Valve Prosthesis ,Humans ,Mitral Valve ,Female ,Tomography, X-Ray Computed ,Echocardiography, Transesophageal ,Aged - Published
- 2015
43. Functional Roles of Ca v 1.3(α 1D ) Calcium Channels in Atria
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Kathryn A. Glatter, Qian Zhang, Valeriy Timofeyev, Zhao Zhang, Dipika Tuteja, Reginald I. Low, Nipavan Chiamvimonvat, Yuxia He, Hee-Sup Shin, Yanfang Xu, and Danyan Xu
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medicine.medical_specialty ,Vascular smooth muscle ,Calcium Channels, L-Type ,Heart Ventricles ,Fluorescent Antibody Technique ,In situ hybridization ,Biology ,Cav1.3 ,Mice ,Physiology (medical) ,Internal medicine ,medicine ,Animals ,Myocyte ,Myocytes, Cardiac ,Heart Atria ,RNA, Messenger ,In Situ Hybridization ,Mice, Knockout ,Microscopy, Confocal ,Voltage-dependent calcium channel ,Atrium (architecture) ,Reverse Transcriptase Polymerase Chain Reaction ,Myocardium ,Depolarization ,Electrophysiology ,Mice, Inbred C57BL ,Endocrinology ,Gene Targeting ,biology.protein ,Cardiology and Cardiovascular Medicine - Abstract
Background— Previous data suggest that L-type Ca 2+ channels containing the Ca v 1.3(α 1D ) subunit are expressed mainly in neurons and neuroendocrine cells, whereas those containing the Ca v 1.2(α 1C ) subunit are found in the brain, vascular smooth muscle, and cardiac tissue. However, our previous report as well as others have shown that Ca v 1.3 Ca 2+ channel–deficient mice ( Ca v 1.3 −/− ) demonstrate sinus bradycardia with a prolonged PR interval. In the present study, we extended our study to examine the role of the Ca v 1.3(α 1D ) Ca 2+ channel in the atria of Ca v 1.3 −/− mice. Methods and Results— We obtained new evidence to demonstrate that there is significant expression of Ca v 1.3 Ca 2+ channels predominantly in the atria compared with ventricular tissues. Whole-cell L-type Ca 2+ currents ( I Ca,L ) recorded from single, isolated atrial myocytes from Ca v 1.3 −/− mice showed a significant depolarizing shift in voltage-dependent activation. In contrast, there were no significant differences in the I Ca,L recorded from ventricular myocytes from wild-type and null mutant mice. We previously documented the hyperpolarizing shift in the voltage-dependent activation of Ca v 1.3 compared with Ca v 1.2 Ca 2+ channel subunits in a heterologous expression system. The lack of Ca v 1.3 Ca 2+ channels in null mutant mice would result in a depolarizing shift in the voltage-dependent activation of I Ca,L in atrial myocytes. In addition, the Ca v 1.3 -null mutant mice showed evidence of atrial arrhythmias, with inducible atrial flutter and fibrillation. We further confirmed the isoform-specific differential expression of Ca v 1.3 versus Ca v 1.2 by in situ hybridization and immunofluorescence confocal microscopy. Conclusions— Using gene-targeted deletion of the Ca v 1.3 Ca 2+ channel, we established the differential distribution of Ca v 1.3 Ca 2+ channels in atrial myocytes compared with ventricles. Our data represent the first report demonstrating important functional roles for Ca v 1.3 Ca 2+ channel in atrial tissues.
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- 2005
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44. Right- and left-sided heart catheterization as a quality marker for catheterization laboratories (from the national Veterans Affairs clinical assessment reporting and tracking program)
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Evan P. Carey, Reginald I. Low, Thomas M. Maddox, Kendrick A. Shunk, and Khung Keong Yeo
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medicine.medical_specialty ,Cardiac Catheterization ,Cardiac Care Facilities ,Heart Diseases ,Hospitals, Veterans ,medicine.medical_treatment ,Hypertension, Pulmonary ,Veterans Health ,Coronary Artery Disease ,Coronary artery disease ,Cohort Studies ,medicine.artery ,Internal medicine ,medicine ,Humans ,Pulmonary Wedge Pressure ,Pulmonary wedge pressure ,Veterans Affairs ,Cardiac catheterization ,Aged ,Quality Indicators, Health Care ,Retrospective Studies ,business.industry ,Retrospective cohort study ,Middle Aged ,medicine.disease ,United States ,United States Department of Veterans Affairs ,medicine.anatomical_structure ,Pulmonary artery ,Heart catheterization ,Cardiology ,Vascular resistance ,Cardiology and Cardiovascular Medicine ,business - Abstract
The rate of concurrent right-heart catheterization (RHC) in patients undergoing left-heart catheterization (LHC) for coronary artery disease (CAD) indications or bilateral heart catheterization (BHC) is recommended as a measure of hospital quality, with higher rates suggesting over utilization. Our aim was to describe the prevalence of BHC and abnormal RHC findings in patients undergoing BHC with a primary indication for LHC. A retrospective analysis was performed for patients undergoing cardiac catheterization for CAD indications using the Department of Veterans Affairs Clinical Assessment Reporting and Tracking Program. Patients undergoing catheterization from October 2007 to September 2011 in 76 Veterans Affairs hospitals were included. Among 95,656 patients undergoing catheterization for CAD, 6,611 (6.9%) underwent BHC and 88,929 (93.0%) LHC. Among the patients undergoing BHC, 61.3% had at least 1 of the following abnormal RHC values: mean pulmonary artery (PA) pressure >25 mm Hg, pulmonary capillary wedge pressure (PCWP) >15 mm Hg, or pulmonary vascular resistance (PVR) >3 Woods units. A total of 37.5% of patients had mean PA pressures of 26 to 40 mm Hg and 11.1% had mean PA pressures >40 mm Hg. A total of 34.4% of patients had mean PCWP of 16 to 25 mm Hg and 13.6% had mean PAWP >25 mm Hg. A total of 16.5% of patients had PVR between 3 and 6 WU and 2.9% had PVR >6 WU. A total of 4.3% of patients met formal criteria for pulmonary arterial hypertension (defined as the combination of PA mean >25 mm Hg, PCWP ≤15 mm Hg, and PVR >3). In conclusion, these findings suggest that most BHC were performed for appropriate clinical reasons. Future studies should further explore BHC rate as an effective quality indicator.
- Published
- 2014
45. ELECTROCARDIOGRAPHIC CHARACTERISTICS OF LEFT MAIN CORONARY ARTERY ST-ELEVATION MYOCARDIAL INFARCTION: RESULTS FROM A MULTICENTER REGISTRY
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Ehtisham Mahmud, Kendrick A. Shunk, Stephen W. Waldo, Kelvin Chua, Gagan D. Singh, Krishan Soni, Aaron K. Wong, Jonathan Yap, Gregory W. Barsness, Ehrin J. Armstrong, Reginald I. Low, Jason H. Rogers, Khung Keong Yeo, Paul Jamie McCabe, and David W.M. Muller
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medicine.medical_specialty ,business.industry ,Electrocardiography in myocardial infarction ,medicine.disease ,surgical procedures, operative ,medicine.anatomical_structure ,St elevation myocardial infarction ,Internal medicine ,medicine ,Cardiology ,Myocardial infarction ,cardiovascular diseases ,business ,Cardiology and Cardiovascular Medicine ,Artery - Abstract
Left main coronary artery (LMCA) ST-elevation myocardial infarction (STEMI) is associated with significant morbidity and mortality. The aim of this study is to describe the electrocardiographic (ECG) characteristics correlating with clinical outcomes for patients with LMCA STEMI in a multicenter
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- 2014
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46. Predictors and outcomes of recurrent stent thrombosis: results from a multicenter registry
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Ehrin J, Armstrong, Shiv, Sab, Gagan D, Singh, Wayland, Lim, Khung-Keong, Yeo, Stephen W, Waldo, Mitul, Patel, Ryan, Reeves, John S, MacGregor, Reginald I, Low, Kendrick A, Shunk, Ehtisham, Mahmud, and Jason H, Rogers
- Subjects
Male ,Time Factors ,Coronary Thrombosis ,Incidence ,Age Factors ,Middle Aged ,Coronary Angiography ,California ,Percutaneous Coronary Intervention ,Treatment Outcome ,Recurrence ,Risk Factors ,Multivariate Analysis ,Humans ,Female ,Stents ,Registries ,Platelet Aggregation Inhibitors ,Aged ,Proportional Hazards Models - Abstract
The aim of this study was to determine the incidence, predictors, and outcomes of recurrent stent thrombosis (rST).Patients who had an initial stent thrombosis (ST) develop may be at high risk of rST.We analyzed a multicenter California registry of angiographic definite ST at 5 academic hospitals from 2005 to 2013. A detailed review of the angiogram and procedure was performed of patients with and without rST.Among 221 patients with a median follow-up of 3.3 years, definite or probable rST developed in 29, including 19 with angiographic definite rST. The cumulative hazard ratio (HR) of definite or probable rST was 16% at 1 year and 24% at 5 years, whereas the cumulative HR of angiographic definite rST was 11% at 1 year and 20% at 5 years. Despite similar angiographic results, patients who had rST develop had significantly greater peak creatine kinase at the time of initial ST (mean, 2,655 mg/dl vs. 1,654 mg/dl; p = 0.05) than those without rST. The 3-year rate of major adverse cardiovascular events was 50% for patients with rST compared with 22% for patients with a single ST (p = 0.01). After multivariable adjustment, independent predictors of definite/probable rST were age (HR: 1.4; 95 confidence interval [CI]: 1.1 to 1.8 per 10 years), bifurcation ST (HR: 4.4; 95% CI: 1.8 to 10.9), and proximal vessel diameter (HR: 1.8; 95% CI: 1.1 to 3.2 per millimeter).rST represents an important cause of long-term morbidity and mortality after an initial ST. Bifurcation ST and a larger proximal reference vessel diameter are independently associated with an increased risk of rST.
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- 2014
47. TCT-703 Accuracy and Procedural Characteristics of Radiofrequency Compared With Standard Needle Transseptal Puncture for Structural Heart Interventions
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Gagan D. Singh, Thomas W. Smith, Dali Fan, Gaurav Sharma, Reginald I. Low, and Jason H. Rogers
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medicine.medical_specialty ,business.industry ,Psychological intervention ,medicine ,Cardiology and Cardiovascular Medicine ,business ,Surgery - Abstract
Targeted transseptal (TS) puncture is an essential technique for many structural heart interventions. Spatial accuracy of standard versus radiofrequency (RF) needles has not previously been reported. Consecutive patients undergoing left-sided structural heart interventions requiring TS puncture
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- 2015
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48. Angiographic characteristics of definite stent thrombosis: role of thrombus grade, collaterals, epicardial coronary flow, and myocardial perfusion
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Ryan R, Reeves, Mitul, Patel, Ehrin J, Armstrong, Shiv, Sab, Stephen W, Waldo, Khung-Keong, Yeo, Kendrick A, Shunk, Reginald I, Low, Jason H, Rogers, and Ehtisham, Mahmud
- Subjects
Male ,Collateral Circulation ,Kaplan-Meier Estimate ,Suction ,Coronary Angiography ,Severity of Illness Index ,California ,Percutaneous Coronary Intervention ,Predictive Value of Tests ,Risk Factors ,Coronary Circulation ,Odds Ratio ,Humans ,Registries ,Aged ,Retrospective Studies ,Thrombectomy ,Academic Medical Centers ,Chi-Square Distribution ,Coronary Thrombosis ,Myocardial Perfusion Imaging ,Middle Aged ,Protective Factors ,Logistic Models ,Treatment Outcome ,Multivariate Analysis ,Female ,Stents ,Blood Flow Velocity - Abstract
To characterize the prevalence of thrombus burden, collateral vessels to the infarct-related artery, epicardial coronary artery flow, and myocardial perfusion in patients with angiographically confirmed definite stent thrombosis (ST), and to define their relationship with associated treatments and outcomes.Angiographic characteristics of ST are not well defined.All cases of angiographically determined ST at five academic hospitals from 2005 to 2012 were reviewed. Demographic, procedural, and angiographic characteristics were recorded. In-hospital and 1-year follow-up data were obtained.Among 205 cases of angiographic definite ST (60 ± 8 years; 87% male), the majority presented with late/very late ST (69%) and STEMI (66%). High-risk angiographic findings at presentation included thrombus grade 4-5 (87%), absence of collateral vessels (76%), and reduced initial TIMI 3 flow (90%). Final TIMI 3 flow was achieved in 90% of patients and was associated with greater use of aspiration thrombectomy (60% vs. 25%; P = 0.003), glycoprotein IIb/IIIa inhibitors (80% vs. 30%, P 0.001), and repeat stenting (67% vs. 10%, P 0.001). A final myocardial perfusion grade of 2-3 was achieved in 79% of patients and was associated with greater use of aspiration thrombectomy (61% vs. 36%, P = 0.003). After multivariable logistic regression, aspiration thrombectomy (AOR 2.6, 95% CI 1.3-5.2) and implantation of a new stent (AOR 2.1, 95% CI 1.1-4.3) were associated with optimal combined epicardial flow and myocardial perfusion. At 1-year follow-up, significantly lower risk of repeat ST (HR 0.1; 95% CI 0.1,0.2; P 0.001) among patients with initial TIMI 3 flow at index ST was observed.The majority of ST patients present with late/very late ST with high thrombus burden and STEMI. Presence of collateral vessels and low thrombus burden is cardioprotective, while reduced initial TIMI flow is associated with larger infarct size and recurrent ST. Aspiration thrombectomy and repeat stenting are associated with improved epicardial coronary artery flow and myocardial perfusion among patients treated for ST. © 2014 Wiley Periodicals, Inc.
- Published
- 2014
49. Procedural success and long-term outcomes of aspiration thrombectomy for the treatment of stent thrombosis
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Stephen W, Waldo, Ehrin J, Armstrong, Khung-Keong, Yeo, Mitul, Patel, Ryan, Reeves, John S, Macgregor, Reginald I, Low, Ehtisham, Mahmud, Jason H, Rogers, and Kendrick, Shunk
- Subjects
Male ,Time Factors ,Coronary Thrombosis ,Hemodynamics ,Kaplan-Meier Estimate ,Middle Aged ,Suction ,Coronary Angiography ,California ,Percutaneous Coronary Intervention ,Treatment Outcome ,Risk Factors ,Coronary Circulation ,Humans ,Female ,Stents ,Prospective Studies ,Registries ,Aged ,Thrombectomy - Abstract
Stent thrombosis (ST) is associated with a significant burden of coronary thrombus and potential microvascular obstruction. Aspiration thrombectomy may decrease the extent of microvascular obstruction in patients with acute myocardial infarction but its role in the treatment of ST is uncertain. The present study sought to evaluate the association between aspiration thrombectomy, procedural success and long-term outcomes among patients presenting with ST.In a multicenter cohort of patients with definite ST, procedural success, long-term mortality, and major adverse cardiovascular events (death, stroke, re-infarction, revascularization) were ascertained. Propensity weighting was used to determine the association between aspiration thrombectomy and long-term outcomes.A total of 205 patients with ST were identified. Among these, 115 (56%) patients underwent adjunctive aspiration thrombectomy during percutaneous coronary intervention. Patients undergoing aspiration thrombectomy were more likely to present with ST-elevation myocardial infarction (75% vs. 52%, P 0.003) and require hemodynamic support (19% vs. 10%, P = 0.07). Aspiration thrombectomy was associated with improved procedural outcomes including postprocedural TIMI 3 flow, resulting in higher angiographic and procedural success (each 96% vs. 83%, P0.001). Despite improved angiographic outcomes, the use of aspiration thrombectomy was not associated with a difference in long-term mortality (adjusted HR 0.99, 95% CI 0.44-2.24) or major adverse cardiovascular events (adjusted HR 1.06, 95% CI 0.45-2.48).Aspiration thrombectomy is associated with improved coronary flow and procedural success but is not associated with improved long-term outcomes among patients undergoing percutaneous intervention for definite ST.NCT00931502 (http://www.clinicaltrials.gov/ct2/show/NCT00931502)
- Published
- 2012
50. EVEREST II Functional Mitral Regurgitation
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Reginald I. Low, Ehrin J. Armstrong, and Jason H. Rogers
- Subjects
medicine.medical_specialty ,Mitral regurgitation ,business.industry ,Inferior Myocardial Infarction ,MitraClip ,medicine.disease ,Ventricular aneurysm ,Left Ventricular Aneurysm ,Internal medicine ,cardiovascular system ,Cardiology ,Medicine ,Functional mr ,cardiovascular diseases ,business ,Functional mitral regurgitation - Abstract
This case example describes in a step-by-step fashion the evaluation and management of severe MR in a patient with functional MR due to an inferior-basal left ventricular aneurysm in the setting of prior inferior myocardial infarction.
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- 2012
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