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RF Ablation of VT in Chronic Cocaine Users Background Cocaine use is a known but rare cause of cardiac arrhythmias. Ventricular arrhythmias related to cocaine may not respond to antiarrhythmic drugs and may need treatment with radiofrequency ablation. Objectives We describe the clinical and electrophysiological characteristics of cocaine-related ventricular tachycardia (VT) from a multicenter registry. Methods Subjects presenting with VT related to cocaine use and being considered for radiofrequency ablation have been included in the study. Patients who were refractory to maximal medical therapy underwent radiofrequency ablation of the VT. Clinical, procedural variables, efficacy, and safety outcomes were assessed. Results A total of 14 subjects met study criteria (age 44 ± 13, range 18- to 68-year-old with 79% male, 71% Caucasian). MRI showed evidence of scar only in 43% of patients (6/14). The mechanism of VT was focal in 50% (n = 7) and scar related reentry in 50% (n = 7) based on 3D mapping. The mean VT cycle length was 429 ± 96 milliseconds. The site of origin was epicardial in 16% (3/18) of VTs. Most clinical VTs were hemodynamically stable (75%). Mean ejection fraction at the time of admission was 44 ± 14%. Duration of procedure was 289 ± 50 minutes. One subject developed pericardial tamponade requiring drainage. At 18 ± 11 months follow-up, freedom from arrhythmia was seen in 86% (1 case lost to follow-up and 2 died). Conclusion Radiofrequency ablation is not only feasible but also safe and effective in patients who have drug refractory VT related to chronic cocaine use. © 2014 Wiley Periodicals, Inc.

Introduction: Catheter ablation (CA) can interfere with cardiac implantable electronic device (CIED) function. The safety of CA in the 1st year after CIED implantation/lead revision is uncertain., Methods: This single center, retrospective cohort included patients who underwent CA between 2012 and 2017 and had a CIED implant/lead revision within the preceding year. We assessed the frequency of device/lead malfunctions in this population., Results: We identified 1810 CAs in patients between 2012 and 2017, with 170 CAs in 163 patients within a year of a CIED implant/lead revision. Mean age 68 ± 12 years (68% men). Time between the CIED procedure and CA was 158 ± 99 days. The CA procedures included AF ablation (n = 57, 34%), AV node ablation (n = 40, 24%), SVT ablation (n = 37, 22%), and PVC/VT ablations (n = 36, 21%). The cumulative frequency of lead dislodgement, significant CIED dysfunction, and/or CIED-related infection following CA was (n = 1/170, 0.6%). There was a single atrial lead dislodgement (0.6%). There were no instances of power-on-reset or CIED-related infection. Following CA, there was no significant difference in RA or RV lead sensing (p = 0.52 and 0.84 respectively) or thresholds (p = 0.94 and 0.17 respectively). The RA impedance slightly decreased post-CA from 474 ± 80 Ohms to 460 ± 73 Ohms (p = 0.002), as did the RV impedance (from 515 ± 111 Ohms to 497 ± 98 Ohms, p < 0.0001)., Conclusions: CA can be performed within 1 year following CIED implantation/lead revision with a low risk of CIED/lead malfunction or lead dislodgement. The ideal time to perform CA after a CIED remains uncertain., (© 2024 Wiley Periodicals LLC.)

Background: The subcutaneous ICD (S-ICD) is a viable alternative to transvenous ICD and avoids intravascular complications in patients without a pacing indication. The outcomes of S-ICD implantation are uncertain in patients with prior sternotomy., Objective: We aim to compare the implant techniques and outcomes with S-ICD implantation in patients with and without prior sternotomy., Methods: Multicenter retrospective cohort study including adult patients with an S-ICD implanted between January 2014 and June 2020. Outcomes were compared between patients with and without prior sternotomy., Results: Among the 212 patients (49 ± 15 years old, 43% women, BMI 30 ± 8 kg/m 2 , 68% primary prevention, 30% ischemic cardiomyopathy, LVEF median 30% IQR 25%-45%) who underwent S-ICD implantation, 47 (22%) had a prior sternotomy. There was no difference in the sensing vector (57% vs. 53% primary, p = 0.55), laterality of the S-ICD lead to the sternum (94% vs. 96% leftward, p = 0.54), or the defibrillation threshold (65 ± 1.4 J vs. 65 ± 0.8 J, p = 0.76) with versus without prior sternotomy. The frequency of 30-day complications was similar with and without prior sternotomy (n = 3/47 vs. n = 15/165, 6% vs. 9%, p = 0.56). Over a median follow-up of 28 months (IQR 10-49 months), the frequency of inappropriate shocks was similar between those with and without prior sternotomy (n = 3/47 and n = 16/165, 6% vs. 10%, p = 0.58)., Conclusion: Implantation of an S-ICD in patients with prior sternotomy is safe with a similar risk of 30-day complications and inappropriate ICD shocks as patients without prior sternotomy., (© 2022 Wiley Periodicals LLC.)

Background: Patients with left ventricular assist devices (LVAD) often tolerate ventricular arrhythmias (VA). We aim to assess the frequency and outcomes of ICD therapies averted by ultraconservative ICD programming (UCP) in LVAD patients., Methods: This single center, retrospective cohort study included patients with LVADs and ICDs implanted from 2015 to 2019 that had UCP. The aim for UCP was to maximally delay VA treatments and maximize anti-tachycardia pacing (ATP) prior to ICD shocks. VA events were reviewed after UCP and evaluated under prior conservative programming to assess for potentially averted events (that would have resulted in either ATP or defibrillation with prior programming)., Results: Fifty patients were included in the study with follow-up of median 16 ± 10.2 months after UCP. The median time from LVAD implantation to reprogramming was 7 days (IQR 5-9 days). Fourteen patients (28%) had potentially averted VA events that would have been treated with their prior ICD programming (82 total events, median two events per patient, IQR 1-10 events). Treated VA events occurred in 15 patients (30%). Eleven of the 14 patients with potentially averted VAs had treated events as well. Only one patient reported definitive symptoms of self-limited "dizziness" during a potentially averted event that did not result in hospitalization. No patients died of complications from or needed emergent care/hospitalization due a potentially averted VA., Conclusions: UCP in LVAD patients likely prevented unnecessary VA treatments in many patients with minimal reported symptoms during these potentially averted events. Prospective studies are necessary to confirm these findings., (© 2022 Wiley Periodicals LLC.)

Background: The fibrous capsule around cardiac implantable device generators is known to promote bacterial colonization and latent infection. Removal of the capsule during device replacement procedures may reduce infection rates but may increase hemorrhagic complications., Objective: The purpose of this study was to evaluate the effect of pocket capsule decortication procedure on infection and bleeding rates in patients undergoing device replacement procedures., Methods: In a prospective randomized single-blind control study, patients undergoing device replacement, upgrade, or lead extraction were randomized to Group A "with pocket revision" (n = 131) and group B "without pocket revision" (n = 127). Deep and superficial infection rates, bleeding, and prolonged serous drainage were assessed during 12 months of follow-up. Data were analyzed according to intention-to-treat principle., Results: A total of 258 patients were enrolled in the study. Rates of generator change, upgrade, and lead extraction/replacement were similar between both groups. There was no incidence of deep infection in either group at 12-month follow-up. There was no significant difference in the incidence of superficial infection between groups (1.5% vs 4.7%, P = .13) during 12-month follow-up. There was a significant increase in acute hematoma formation in group A compared to group B (6.1% vs 0.8%, P = .03). Two patients in group A had to undergo hematoma evacuation., Conclusion: There was increased incidence of hematoma formation in group A with no effect on infection rates. Our study suggests that there is no benefit to performing empiric pocket revision., (Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Despite ACC/AHA guidelines indicating implantable cardioverter defibrillator (ICD) as class I therapy for primary prevention of sudden cardiac death in patients with EF≤35%, ICD utilization rates in real world practice have been low., Objective: To determine the rate of ICD implantation at a tertiary care academic center and to assess the reasons for under-utilization of the same., Methods: Review of a prospectively collected database which included all patients diagnosed with an EF≤35% was performed to assess the rate of ICD implantation and mortality. Reasons for non-implantation of ICD were then assessed from detailed chart review., Results: A total of 707 patients (age 69.4 ± 14.1 years) with mean EF of 26±7% were analyzed. Only 28% (200/707) of patients had ICDs implanted. Mortality was lower in the group with ICD (25% vs 37%, p=0.004). When patients who either died or were lost to follow-up prior to 2005 were excluded, ICD utilization rate was still low at 37.6%. The most common reason for non-implantation of ICD was physicians not discussing this option with their patients. Patient refusal was the second most common reason., Conclusions: ICD Implantation rates for primary prevention of SCD in patients with EF≤35% is low. Physician and patient education should be addressed to improve the utilization rates.

Background: Pre- and postablation atrial fibrillation (AF) brain natriuretic peptide (BNP) levels were shown to predict increased recurrence of AF following ablation., Objective: Our objective was to assess whether elevated BNP levels merely represent the presence of AF at the time of measurement or indeed the true recurrence of AF., Methods and Results: In a prospective study of 88 patients undergoing AF ablation, BNP levels were measured immediately before, after, 24 h, and 4-6 months postablation. BNP levels were stratified by presenting rhythm and ventricular rate at the time of measurement. Median BNP level preablation was higher in patients presenting in AF compared to sinus rhythm (SR) (54(44-79) pg/ml vs. 30(18-47) pg/ml, p < 0.001). Postablation restoration of SR in patients presenting in AF reduced median BNP levels from 54(44-79) pg/ml to 40(37-51) pg/ml, (p < 0.001). However, no change was noted in patients who presented in and maintained SR throughout the procedure (30(18-47) pg/ml to 27(16-40) pg/ml, p = 0.270). At 4-6 months, BNP measured in patients in SR was not significantly different from postablation BNP (35(22-53) pg/ml vs. 38(20-52) pg/ml, p = 0.656), although 35% of them had AF recurrence in 1-year follow-up. Median BNP level measured in five patients while in atrial arrhythmia was elevated compared to postablation BNP (464(421-464) pg/ml to 37(36-37) pg/ml, p = 0.043). BNP levels and ventricular rates are positively correlated at all times pre- and postablation., Conclusions: BNP level rises acutely during AF and with rapid ventricular rates. BNP level seems to be a function of atrial rhythm and ventricular rate rather than short- or long-term predictor of AF ablation success.

Atrial fibrillation (AF) is a very common tachyarrhythmia and is becoming increasingly prevalent, while dementia is a neurological condition manifested as loss of memory and cognitive ability. Both these conditions share several common risk factors. It is becoming increasingly evident that AF increases the risk of dementia. There are several pathophysiological mechanisms by which AF can cause dementia. AF increases the stroke risk and strokes are strongly associated with dementia. Besides stroke, altered cerebral blood flow in AF and cerebral microbleeds from anticoagulation may enhance the risk of dementia. Maintaining sinus rhythm may therefore decrease this risk. Catheter ablation is emerging as an effective alternative to maintain patients in sinus rhythm. This procedure has also shown promise in decreasing the risk of all types of dementia. Besides maintaining sinus rhythm and oral anticoagulation, aggressive risk factor modification may reduce the likelihood or delay the onset of dementia.

Background: Radiation exposure in the electrophysiology (EP) lab is a major concern to most electrophysiologists. A new technology, MediGuide™ nonfluoroscopic catheter tracking system, has been used for the first time in the USA recently. We intended to evaluate the efficacy of this novel catheter tracking system in reducing radiation exposure., Methods: We performed a prospective observational study by comparing the radiation exposure with MediGuide™ system to that of conventional mapping systems. The first 45 EP procedures performed with the MediGuide™ system were compared to 45 matched patients undergoing similar procedures during the same time frame using conventional mapping systems (CARTO and NavX) and fluoroscopy. We collected and compared baseline characteristics, procedural variables including fluoroscopic exposure between both groups., Results: Forty-five patients underwent EP procedures using the MediGuide™ technology. They were matched with an equal number of patients with conventional mapping systems. Of the 45 patients included in the study, 33 underwent right atrial flutter ablations, 5 underwent atrioventricular nodal reentrant tachycardia ablations, 4 underwent ablation of Wolf-Parkinson-White syndrome, and 3 underwent EP studies with no ablation. There were no differences in mean age, gender distribution, and body mass index between the groups. Procedure duration in the MediGuide™ group was significantly lower than the duration in the conventional group (103 vs. 142 min, p = 0.03). The fluoroscopic time was significantly less during the procedures performed with the MediGuide™ technology when compared to the control group (8 vs. 21 min, p < 0.001). No major complications occurred during the procedures in either group., Conclusion: MediGuide™, a new nonfluoroscopic catheter tracking system, is associated with more than a 50 % reduction in fluoroscopic time when compared to conventional mapping systems.

Background: Fluoroscopic radiation has been implicated in reducing the sex ratio (M:F) by potentially damaging the Y chromosome. We examined the effects of exposure to fluoroscopic radiation on gender of offspring of cardiologists across the world. Methods: An internet based survey was e-mailed worldwide to 8000 physicians who practice invasive electrophysiology and/or interventional cardiology. Survey questions included age, race, sub-specialty, hours of exposure to radiation, number of children, gender of off-spring, miscarriages and mutations and exposure to radiation prior to conception of each child. Logistic regression analyses were performed on years of exposure and gender of offspring born post radiation exposure. Results: Responses of 377 cardiologists (84% male and 16% female) were reviewed. With a total of 398 males and 402 females born to 377 cardiologists, although reduced, the overall sex ratio (0.99) was not significantly different from that observed in the general population (1.05). Univariate logistic regression analysis identified higher male births with increasing hours of radiation exposure (OR 1.034, CI 1.003-1.067 p=0.03) and increasing paternal age (OR 1.05, CI 1.01-1.08, p=0.002). Subgroup analysis of children of male cardiologists revealed higher incidence of male births with increasing age and radiation exposure and multivariate analysis only identified paternal age as predictor of higher incidence of male births (OR 1.05, CI 1.01-1.089, p=0.0027). Conclusion: Exposure to ionizing radiation leads to a decrease in the sex ratio (M/F) in younger male cardiologists, while this effect is reversed with greater number of male births in older male cardiologists.

We describe the first case of cardiac arrhythmia ablation with the novel MediGuide TM non-fluoroscopic catheter tracking system in North America. This new technology uses electromagnetic field to track sensor integrated intracardiac electrophysiology catheters which are projected on pre-recorded fluoroscopy cine loops. This new technology permits catheter tracking in virtual biplane fluoroscopy and enhances spatial resolution of conventional 3D mapping systems while drastically reducing radiation exposure.

Background: Patients with prosthetic valves have a high prevalence of atrial fibrillation (AF). We report a multicenter experience of performing pulmonary vein antral isolation (PVAI) in this challenging, high-risk cohort of patients., Objective: The purpose of this study was to assess the feasibility, safety, and efficacy of radiofrequency (RF) ablation for sinus rhythm restoration in AF patients with mitral or aortic mechanical prosthetic valves., Methods: A total of 50 patients with prosthetic valves (group I) who underwent RF ablation for AF between January 1, 2007, and April 30, 2009, were identified prospectively at four tertiary care centers. A matched group of 50 patients (group II) acted as controls., Results: Total procedural time (199.4 ± 49 minutes vs 166.6 ± 27.5 minutes, P <.001) and fluoroscopy time (60 ± 17 minutes vs 53.8 ± 6.8 minutes, P <.01) were prolonged, with a higher incidence of atrial flutter at 3 months in group I (18% vs 6%, P = .1) compared to group II. At 12 months, 80% of patients in the valve group were in sinus rhythm after an average of 1.3 procedures, and 82% of controls were in sinus rhythm after an average 1.2 procedures (P = .9). There was a trend toward a higher nonfatal complication rate in the valve group than in the control group (8% vs 4%, P = .1)., Conclusion: In patients with prosthetic valves, RF ablation for AF is feasible, safe, and efficacious, with a trend toward a higher nonfatal complication rate and an increased rate of postablation atrial flutter., (Copyright © 2011. Published by Elsevier Inc.)

Atrial septal defects constitute the second most common cardiac congenital abnormality. These defects when undiagnosed during childhood, present in adulthood with symptoms of right heart failure. We describe a case of uncorrected ostium primum atrial septal defect that presented as liver failure in a 43-year-old woman. The patient was found to have liver cirrhosis and a complete work-up of hepatic causes for cirrhosis was negative. Further examination revealed an atrial primum septal defect. Liver cirrhosis in this patient was thought to be secondary to chronic congestion from the right heart failure resulting from the atrial septal defect. Although right heart failure is a known cause of cirrhosis, liver cirrhosis resulting specifically from an atrial septal defect is uncommon. In fact, an ostium primum atrial septal defect presenting as liver cirrhosis has not been well described. We present such a case to highlight this manifestation of atrial septal defect and also to reiterate that cardiac causes should always be considered in the differential diagnosis whenever a patient presents with liver cirrhosis.

Management of ventricular tachycardia (VT) storm in a patient with an implantable cardioverter-defibrillator (ICD) is a challenging medical emergency. We describe a patient with cardiac sarcoidosis (CS) and an ICD who is admitted with VT storm. Management of VT was difficult due to resistance to multiple antiarrhythmic drugs. He responded to immunosuppressive therapy supporting active CS as the cause of his VT. This case suggests that CS may underlie some cases of refractory VT and that immunosuppressive therapy may be effective in controlling this arrhythmia.

A 31-year-old female underwent an electrophysiology procedure wherein 4 vascular sheaths were placed. Following the procedure, as one of the vascular sheaths was pulled out, clinicians noted that it was broken. Emergent fluoroscopy revealed part of the vascular sheath was left behind in the soft tissue and was removed surgically. This case report describes the complications associated with vascular sheaths and reiterates the correct methods of handling them.

Unlabelled: Intracardiac Echo-Guided Radiofrequency Catheter., Introduction: Patients with atrial septal defect (ASD) are at higher risk for atrial fibrillation (AF) even after repair. Transseptal access in these patients is perceived to be difficult. We describe the feasibility, safety, and efficacy of pulmonary vein antral isolation (PVAI) in these patients., Method: We prospectively compared post-ASD/patent foramen ovale (PFO) repair patients (group I, n = 45) with age-gender-AF type matched controls (group II, n = 45). All the patients underwent PVAI through a double transseptal puncture with a roving circular mapping catheter technique guided by intracardiac echocardiography (ICE). The short-term (3 months) and long-term (12 month) failure rates were assessed., Results: In group I, 23 (51%) had percutaneous closure devices and 22 (49%) had a surgical closure. There was no significant difference between group I and II in the baseline characteristics. Intracardiac echo-guided double transseptal access was obtained in 98% of patients in group I and in 100% of patients in group II. PVAI was performed in all patients, with right atrial flutter ablation in 7 patients in group I and in 4 patients in group II. Over a mean follow-up of 15 +/- 4 months, group I had higher short-term (18% vs 13%, P = 0.77) and long-term recurrence (24% vs 18%, P = 0.6) than group II. There was no significant difference in the perioperative complications between the two groups. Echocardiography at 3 months showed interatrial communication in 2 patients in group I and 1 patient in group II, which resolved at 12 months., Conclusion: Percutaneous AF ablation using double transseptal access is feasible, safe, and efficacious in patients with ASD and PFO repairs.

Background: Under utilization of warfarin in elderly patients with atrial fibrillation (AF) has been recognized as a significant health care issue. This study examines the rate and reasons for warfarin underutilization in elderly patients with AF at the Kansas City Veterans Affairs Medical Center. Methods: Retrospective study reviewing electronic medical records of all patients aged 65 and older with the diagnosis of atrial fibrillation. Patients on warfarin were excluded. Reasons for not using warfarin were extracted by reviewing the electronic medical record. Anticoagulation indications for these patients were determined based on the ACC/AHA/ESC 2006 Guidelines for the Management of Patients with Atrial Fibrillation. Results: Warfarin was not used by 407 patients (25%) with known AF. Average age was 79+6.2 years. 60% of patients had persistent or permanent AF. Prevalence of risk factors for thromboembolism included hypertension (74%), heart failure or ejection fraction of <40% (21%), diabetes (27%) and coronary artery disease (48%). CHADS (2) scores were documented in the charts less than 1% of the times. Only 11 patients had CHADS (2) score of 0 and 70 had a score of 1. A class I or IIa indication for warfarin therapy was present in 298 (73%) of patients. Return to sinus rhythm (37%) was the most common reason for not using warfarin. In 30% of cases the reason not to use warfarin was not addressed. Other reasons not to use warfarin included fear of falls (7%), prior head or GI bleed (14%), patient refusal & noncompliance (12%). History of CVA or TIA was documented in 12% of patients. Conclusions: Underutilization of warfarin in elderly patients with atrial fibrillation remains a common problem despite their high risk for thromboembolic events. A false sense of security about the paroxysmal nature of AF, lack of proper insight about stroke risk (CHADS (2)), and fear of bleeding are the most common reasons for non use of warfarin.

Radiofrequency Ablation of AV node with permanent pacemaker has been used to achieve rate control in persistent symptomatic atrial fibrillation. Although RF Ablation is safe, complications may occur in up to 3% of the procedures. A rare complication of 2nd degree skin burn at indifferent electrode site has been described here. This report highlights the rare but possible complication in patients undergoing such a procedure and help in preventing by taking appropriate measures.

To evaluate the effectiveness of percutaneous transluminal coronary angioplasty (PTCA) in the treatment of myocardial infarction, we reviewed the records of 508 consecutive patients treated within 6 hours of pain onset. Two hundred fifty-eight patients received direct PTCA without thrombolytic therapy, and 250 received thrombolytic therapy followed by immediate PTCA (within 24 hours, n=73) or delayed PTCA (later than 24 hours, n=177). The direct-PTCA group had the lowest initial success rate (92%) and the highest 1-week (8.1%) and 1-year (14%) mortality rates. Immediate PTCA had a 96% success rate, and 6.8% 1-week and 8.2% 1-year mortality rates. Delayed PTCA had the same initial success (96%), but lower 1-week (1.7%) and 1-year (2.3%) mortality. We conclude that both direct PTCA and combination treatment (thrombolytic therapy followed by PTCA) result in high rates of recanalizing occluded coronary arteries, but that combination treatment has higher initial success and survival rates, with delay in the use of PTCA producing the best survival rates.