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The great saphenous vein (GSV) has served as a coronary artery bypass graft (CABG) conduit for over 50 years. Despite prevalent use, first-year failure rates remain high compared to arterial autograft options. Amongst other factors, vein graft failure can be attributed to material and mechanical mismatching that lead to apoptosis, inflammation, and intimal-medial hyperplasia. Through the implementation of the continuum mechanical-based theory of "stress-mediated growth and remodeling," we hypothesize that the mechanical properties of porcine GSV grafts can be favorably tuned for CABG applications prior to implantation using a prolonged but gradual transition from venous to arterial loading conditions in an inflammatory and thrombogenic deficient environment. To test this hypothesis, we used a hemodynamic-mimetic perfusion bioreactor to guide remodeling through stepwise incremental changes in pressure and flow over the course of 21-day cultures. Biaxial mechanical testing of vessels pre- and post-remodeling was performed, with results fit to structurally-motivated constitutive models using non-parametric bootstrapping. The theory of "small-on-large" was used to describe appropriate stiffness moduli, while histology and viability assays confirmed microstructural adaptations and vessel viability. Results suggest that stepwise transition from venous-to-arterial conditions results in a partial restoration of circumferential stretch and circumferential, but not axial, stress through vessel dilation and wall thickening in a primarily outward remodeling process. These remodeled tissues also exhibited decreased mechanical isotropy and circumferential, but not axial, stiffening. In contrast, only increases in axial stiffness were observed using culture under venous perfusion conditions and those tissues experienced moderate intimal resorption. [ABSTRACT FROM AUTHOR]

Stroke is a major adverse event in patients developing atrial fibrillation (AF) after cardiac surgery. Surgical left atrial appendage amputation/ligation (LAA-A/L) during off-pump coronary artery bypass grafting (OPCAB) is routinely performed in our institution. We analyzed 578 consecutive patients (mean age 69 years, male 82%) undergoing OPCAB with or without concomitant LAA-A/L from 2011 to 2014 at our institution in a prospective observational manner. The safety and efficacy of the concomitant LAA-A/L on preventing early (<30 days) and overall postoperative stroke were examined. A total of 193 patients (33.4%) underwent LAA-A/L, consisting of amputation in 154 and ligation in 39 patients (80 and 20% of the cases, respectively). Preoperative characteristics, operative time, requirement of blood transfusion, and 30-day mortality were not significantly different between those with and without LAA-A/L. The incidences of postoperative AF and early and overall stroke were not significantly different between the groups in the analysis based on a total cohort. In a subanalysis of patients without LAA-A/L, early and overall stroke occurred more frequently in those developing postoperative AF than those without AF (2.8 vs. 0%; p = 0.005, 6.2 vs. 1.5%; p = 0.017, respectively), while in patients receiving LAA-A/L, stroke incidences did not differ between those with and without AF. Multivariate logistic regression showed postoperative AF without LAA-A/L as the only independent positive predictor of overall stroke (OR 3.69, p = 0.03). Concomitant LAA-A/L with OPCAB can safely prevent postoperative stroke occurrence in case patients develop AF, the most common arrhythmia associated with stroke. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of a bypass in terms of determining the optimal parameters of shunt operation. The equations that describe the propagation of pressure pulse waves in blood vessels are presented in differential form and in approximate form for the averaged values based on the conservation laws. The correspondence of these forms is shown from the solution of the initial-boundary-value problem for vascular junction. The influence of the parameters such as various diameters, wall thicknesses, and elastic properties of blood vessels on the shunt effectiveness is investigated. In particular, we investigate the influence of the shunt form and junction area, as well as the angle of the shunt connection with the vessel, on the passage of the coronary vessels and blood coagulation. On the basis of the calculations, conclusions about the influence of various parameters on the dynamics of bypass are made. [ABSTRACT FROM AUTHOR]

Cystic adventitial disease (CAD) of the popliteal artery is a rare vascular disorder in which a mucin-containing cyst develops in the adventitial layer of the artery. We report two such cases, each of which was treated differently. The first case was of a 49-year-old man, treated by excision of the involved arterial segment and interposition of an autologous saphenous vein graft. The second case was of a 36-year-old man, treated by local excision of the affected arterial segment and interposition with prosthetic bypass grafting. Both patients presented with rapidly progressing intermittent claudication of the lower extremities, but without remarkable evidence of atherosclerotic disease. Physical examination revealed diminished or absent popliteal, posterior tibial and dorsalis pedis pulses in the lower extremities. Color Doppler ultrasound of the popliteal artery revealed hypoechoic cystic lesions surrounding the vessel, and popliteal arterial stenosis, in both patients. Surgery resulted in immediate improvement of the arterial pulse distal to the lesion. Both patients recovered uneventfully. Thus, resection of the involved artery segment and interposition bypass grafting, using either patient or prosthetic veins, offers favorable results for CAD of the popliteal artery. [ABSTRACT FROM AUTHOR]

We report a case of axillary artery aneurysm with brachial artery embolism in a 60-year-old man who had walked with the assistance of axillary crutches all of his life since poliomyelitis during infancy had left him with lower limb paralysis. We performed bypass grafting from the axillary to brachial artery with exclusion of the aneurysm. An axillary artery aneurysm is rare, but potentially lethal for the upper extremity; therefore, surgical treatment should be considered. [ABSTRACT FROM AUTHOR]

We briefly and comprehensively present some of the novel findings in the field of revascularization therapy and management of ST-segment-elevation myocardial infarction (STEMI). We highlight the latest evidence-based advancements in the pharmacological and mechanical treatment of patients who presented with STEMI. Since the last updates to the international guidelines (American College of Cardiology/American Heart Association and the European Society of Cardiology) were published in 2011 and 2012, there have been changes and several important studies have presented their final outcomes. We also highlight some controversial approaches as part of the current debates in the cardiology community. In addition, we share our recent experience in the field of biodegradable scaffold stents as a treatment strategy in STEMI. [ABSTRACT FROM AUTHOR]

Purpose: In this study we evaluated the diagnostic performance of Tc-HMPAO-leucocyte (Tc-HMPAO-WBC) scintigraphy in a consecutive series of 55 patients (46 men and 9 women, mean age 71 ± 9 years, range 50 - 88 years) with a suspected late or a low-grade late vascular prosthesis infection (VPI), also comparing the diagnostic accuracy of WBC with that of other radiological imaging methods. Methods: All patients suspected of having VPI underwent clinical examination, blood tests, microbiology, US and CT, and were classified according to the Fitzgerald criteria. A final diagnosis of VPI was established in 47 of the 55 patients, with microbiological confirmation after surgical removal of the prosthesis in 36 of the 47. In the 11 patients with major contraindications to surgery, the final diagnosis was based on microbiology and clinical follow-up of at least 18 months. Results: Tc-HMPAO-WBC planar, SPECT and SPECT/CT imaging identified VPI in 43 of 47 patients (20 of these also showed infection at extra-prosthetic sites). In the remaining eight patients without VPI, different sites of infections were found. The use of SPECT/CT images led to a significant reduction in the number of false-positive findings in 37 % of patients (sensitivity and specificity 100 %, versus 85.1 % and 62.5 % for stand-alone SPECT). Sensitivity and specificity were 34 % and 75 % for US, 48.9 % and 83.3 % for CT, and 68.1 % and 62.5 % for the FitzGerald classification. Perioperative mortality was 5.5 %, mid-term mortality 12 %, and long-term mortality 27 %. Survival rates were similar in patients treated with surgery and antimicrobial therapy compared to patients treated with antimicrobial therapy alone (61 % versus 63 %, respectively), while infection eradication at 12 months was significantly higher following surgery (83.3 % versus 45.5 %). Conclusion: Tc-HMPAO-WBC SPECT/CT is useful for detecting, localizing and defining the extent of graft infection in patients with late and low-grade late VPI with inconclusive radiological findings. Tc-HMPAO-WBC SPECT/CT might be used to optimize patient management. [ABSTRACT FROM AUTHOR]

We herein report the case of a patient demonstrating both coronary artery and peripheral artery occlusive disease with neurofibromatosis, which were successfully treated during the same session with coronary artery bypass graft surgery and a femoropopliteal bypass graft surgery procedure. The recognition of a possible association between neurofibromatosis and coronary artery and other vascular structures will further facilitate the successful surgery and clinical management of this rare clinical entity. [ABSTRACT FROM AUTHOR]

We describe successful anesthetic management during living-donor liver transplantation in a 63-year-old man with previous coronary artery bypass grafting (CABG) that employed an in situ right gastroepiploic artery (RGEA). Anesthesia was maintained with 1.5% isoflurane in air/oxygen and fentanyl. A five-lead electrocardiogram, transesophageal echocardiogram, and pacing pulmonary artery catheter evaluated cardiac function. A pacing wire was inserted through the catheter to prepare for intraoperative severe bradyarrhythmia. Olprinone and nicorandil were continuously infused to prevent decrease in coronary arterial blood flow and the collapse of cardiac function. Avoiding disruption of circulation to coronary arteries through injury or spasm of the RGEA graft and preparing for cardiac insufficiency during liver transplantation of a patient with previous CABG using an in situ RGEA is critical. [ABSTRACT FROM AUTHOR]

We report our strategy for malperfusion accompanying acute aortic dissection, especially that involving the abdominal organs, which is based on the mechanism and includes percutaneous management. From 1991 through October 2005, a total of 38 of 135 (28%) patients with acute dissection presented with organ malperfusion. Altogether, 31 had type A dissection. The involved vascular territories were coronary in 8, brain in 16, celiac and superior mesenteric in 6, renal in 10, and lower limb in 13. For the abdominal organs, the mechanisms of the malperfusion were classified into the aortic type ( n = 3) and the branch type ( n = 13). The branch type was further divided into the orifice type ( n = 8) and distal type ( n = 5). All but one patient with type A dissection underwent a central aortic operation with resection of the entry site. Revascularization of the ischemic organ was added by bypass grafting or direct reconstruction. Distal organ malperfusion accompanying type B dissection was treated by the mechanism-specific approach. That is, the aortic type was treated by surgical fenestration, whereas the branch type was treated by percutaneous stenting. The one hospital death (2.6%) was due to brain infarction. Although a central aortic operation alone successfully reversed aortic-type malperfusion in all three patients, it was not effective for branch-type malperfusion in five of six vascular territories. Surgical fenestration did not successfully reverse branch-type renal malperfusion in two patients. Percutaneous stenting was successful in all three vessels with branch-type malperfusion. Central aortic operation or fenestration is effective for aortic-type malperfusion, whereas the branch type may require stenting or bypass grafting. [ABSTRACT FROM AUTHOR]

Objective: Internal thoracic artery (ITA) grafts provide better early and long-term patency than saphenous vein (SV) grafts. Furthermore, bilateral ITA grafting has recently demonstrated better long-term results than unilateral ITA grafting. However, its use in the elderly is controversial. Methods: From March 1991 through November 2001, 307 consecutive patients aged 65 years or over undergoing isolated coronary artery bypass grafting (CABG) were reviewed, and the influence of bilateral ITA grafting on the early and long-term results was evaluated. All ITA grafts were harvested as a pedicle, and almost all of which were used as in-situ grafts. Results: Operative mortality in 138 patients undergoing bilateral ITA grafting was 1.4%, and in 108 patients undergoing unilateral ITA grafting, the rate was 0.9%. Predischarge angiography conducted in 97% of the subjects showed that the patency rate of all the ITA grafts (98.9%) was superior (p<0.0001) to that of all the SV grafts (93.6%). In comparisons of survival and freedom from cardiac events at 10 years after CABG, the bilateral use of ITA grafts was proved to be more beneficial than the unilateral use (p<0.05). Conclusions: It was demonstrated that bilateral ITA grafting could be performed with acceptable mortality and morbidity. Moreover, it offers better long-term survival and freedom from cardiac events than either unilateral ITA grafting or no ITA grafting. Bilateral ITA grafting thus can serve as a favorable procedure even in elderly patients. [ABSTRACT FROM AUTHOR]

The EC-IC Bypass Study Group could not detect any benefit from surgery compared to medical management in the prevention of stroke in 1985 [15]. During the past years surgical revascularization was re-evaluated and considered as an appropriate treatment for a small subgroup of patients with recurrent focal cerebral ischaemia and impaired haemodynamics. This retrospective study examines the long-term benefit and patency rate of bypass. We present a follow-up of 5.6 years of 47 patients, all of whom underwent byupass surgery after 1985. Forty patients suffered recurring transient ischaemic attacks due to uni- or bilateral internal carotid artery occlusion. Examination included neurologic status, TCD with CO or Diamox challenge, angiography, CT and SPECT scans. Neurological improvement was seen in 23% of patients with better results after early surgery, a worsening in 22% suffering further ischaemic events on a postoperative average of 2.8 years. Patency rate for vein graft material was 50%, for the STA-MCA procedure 91%. Occlusion of the vein graft occurred on an average after 1.4 years, other anastomosis after 2.7 years. We conclude that only few patients derived long-term benefit from EC-IC bypasses. Functioning of the bypass worsens over time, suggesting a role for surgery predominantly in the first year of ischaemic events due to insufficient collateral supply. Actual indications for bypass surgery may be patients with failure of maximal medical therapy and progressive ischaemia and haemodynamic compromise. [ABSTRACT FROM AUTHOR]

From 1974 to 1976, four patients with juxtarenal aortic occlusion were operated upon with no surgical mortality. Thromboendarterectomy (TEA) of the aorta with renal revascularization was performed in one patient, and TEA with grafting in three. Intraoperative renal protection was particularly important, since suprarenal aortic clamping was often required in these cases. Possible renal embolism developed in one patient postoperatively. In order to prevent renal embolism and to minimize ischemic insult to the kidney, the value of the following procedures was stressed; (a) irrigation of aortic lumen with saline after TEA under suprarenal aortic clamping with renal arteries kept occluded, and (b) re-application of aortic clamp below the renal arteries after irrigation. Since the most distal level of occlusive process was the common femoral artery in our series, the patient with this desease entity should be treated more actively. [ABSTRACT FROM AUTHOR]