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Background: A competent aortic valve is essential to providing effective left ventricular assist device support. We have adopted a practice of central aortic valve closure by placing a simple coaptation stitch at left ventricular assist device implantation in patients with significant aortic insufficiency. We conducted a follow-up study to evaluate the efficacy and durability of this procedure. Methods: The study included patients who had undergone continuous flow left ventricular assist device implantation. The patients were divided into 2 groups, those who did not require any aortic procedure because the valve was competent and those who underwent central aortic valve closure for mild or greater aortic regurgitation. The clinical endpoints were mortality, progression or recurrence of aortic insufficiency, and reoperation for aortic valve pathologic features. Aortic insufficiency was measured qualitatively from mild to severe on a scale of 0 to 5. Results: A total of 123 patients received continuous flow left ventricular assist devices from February 2007 to August 2011. Of those, 18 (15%) underwent central aortic valve closure at left ventricular assist device implantation because of significant aortic insufficiency (1.8 ± 1.4) and 105 who did not (competent aortic valve, 0.15 ± 0.43; P < .01). At follow-up (median, 312 days; range, 0-1429 days), the mean aortic insufficiency score remained low for the patients with central aortic valve closure (0.27 ± 0.46) in contrast to those without central aortic valve closure who experienced aortic insufficiency progression (0.78 ± 0.89; P = .02). In addition, the proportion of patients with more than mild aortic insufficiency was significantly less in the central aortic valve closure group (0% vs 18%; P = .05). The patients in the central aortic valve closure group were significantly older and had a greater incidence of renal failure at baseline. The 30-day mortality was greater in the central aortic valve closure group, but the late survival was similar between the 2 groups. No reoperations were required for recurrent aortic insufficiency. Conclusions: The results of our study have shown that repair of aortic insufficiency with a simple central coaptation stitch is effective and durable in left ventricular assist device-supported patients, with follow-up extending into 2 years. Although aortic insufficiency progressed over time in those with minimal native valve regurgitation initially, no such progression was noted in those with central aortic valve closure. Additional investigation is needed to evaluate whether prophylactic central aortic valve closure should be performed at left ventricular assist device implantation to avoid problematic aortic regurgitation developing over time, in particular in patients undergoing left ventricular assist device implantation for life-long (destination therapy) support. [Copyright &y& Elsevier]

Objective: Warfarin reduces risk of stroke in patients with mechanical heart valves but increases risk of hemorrhage and is difficult to use. Dabigatran etexilate, a new oral direct thrombin inhibitor, is safe and effective in reducing risk of stroke among patients with atrial fibrillation. No data exist in the setting of mechanical heart valves. We tested the hypothesis that dabigatran etexilate is as effective as heparin for thromboprophylaxis of mechanical valves in a porcine heterotopic aortic valve model. Methods: Thirty swine underwent implantation of modified bileaflet mechanical valved conduit bypassing the ligated, native descending thoracic aorta. Animals randomly received no anticoagulation (n = 10), enoxaparin 2 mg/kg subcutaneously twice daily (n = 10), or dabigatran etexilate 20 mg/kg orally twice daily. Primary end point was amount of valve thrombus at 30 days. Secondary end points included quantitative measurement of platelet deposition on valve prosthesis, thromboelastography, and hemorrhagic and embolic events. Results: At 30 days, we observed 638 ± 895 mg thrombus in no anticoagulation group, 121 ± 128 mg in enoxaparin group, and 19 ± 31 mg in dabigatran etexilate group (P = .01 enoxaparin vs dabigatran etexilate). Fewer platelets were deposited on valves in dabigatran etexilate group (2.7 × 108) than in enoxaparin group (1.8 × 109, P = .03). No major or occult hemorrhagic or embolic events were observed. By thromboelastographic analysis, dabigatran etexilate produced less prolongation of K value (P = .01) and less decreases in angle (P = .01) and maximum amplitude (P = .001) than enoxaparin. Conclusions: Dabigatran etexilate is as effective as enoxaparin for short-term thromboprophylaxis of mechanical valves. It prevents valve thrombus and platelet deposition at 30 days without increased adverse events. These promising results serve as a foundation for prospective clinical trials with dabigatran etexilate as an alternative to warfarin in patients with bileaflet mechanical aortic valves. [Copyright &y& Elsevier]

Objective: Most aortic valve replacements are by conventional full median sternotomy. Less invasive approaches have been developed with partial upper sternotomy (ministernotomy). Methods: Systematic review and meta-analysis were performed with studies comparing ministernotomy and full sternotomy for aortic valve replacement. Results: Twenty-six studies were selected, with 4586 patients with aortic valve replacement (2054 ministernotomy, 2532 full sternotomy). There was no difference in mortality (odds ratio 0.71, 95% confidence interval 0.49–1.02). Ministernotomy had longer crossclamp and bypass times (weighted mean difference 7.90 minutes, 95% confidence interval 3.50–10.29 minutes, and 11.46 minutes, 95% confidence interval 5.26–17.65 minutes, respectively). Both intensive care unit and hospital stays were shorter with ministernotomy (weighted mean difference −0.46 days, 95% confidence interval −0.72 to −0.20 days, and −0.91 days, 95% confidence interval −1.45 to −0.37 days, respectively). Ministernotomy had shorter ventilation time and less blood loss within 24 hours (weighted mean difference −2.1 hours, 95% confidence interval −2.95 to −1.30 hours, and −79 mL, 95% confidence interval −23 to 136 mL, respectively). Randomized studies tended to demonstrate no difference between ministernotomy and full sternotomy. Rate of conversion from partial to conventional sternotomy was 3.0% (95% confidence interval 1.8%–.4%). Conclusion: Ministernotomy can be performed safely for aortic valve replacement, without increased risk of death or other major complication; however, few objective advantages have been shown. Surgeons must conduct well-designed, prospective studies of relevant, consistent clinical outcomes to determine the role of ministernotomy in cardiac surgery. [Copyright &y& Elsevier]

Objective: In the interest of exploring alternatives to warfarin, we tested the hypothesis that clopidogrel combined with aspirin is effective for thromboprophylaxis of mechanical valves using a swine model. Methods: Adult swine underwent heterotopic implantation of a modified bileaflet mechanical valved conduit bypassing the ligated, native descending thoracic aorta. Animals were randomized to no anticoagulation (n = 7), 175 U/kg dalteparin administered subcutaneously twice daily (n = 9), 325 mg of aspirin (n = 6), 75 mg of clopidogrel (n = 6), or 325 mg of aspirin and 75 mg of clopidogrel daily (n = 6) and survived for 30 days. Additionally, 11 animals were randomized to no anticoagulation (n = 5) or 325 mg of oral aspirin and 75 mg of clopidogrel daily (n = 6) and survived for 150 days. Results: At 30 days, we observed 216 ± 270 mg of thrombus for the no anticoagulation group, 53 ± 91 mg for the dalteparin group, 33 ± 23 mg for the aspirin group, 25 ± 10 mg for the clopidogrel group, and 17 ± 9 mg for the combined aspirin and clopidogrel group, respectively (P < .01 for clopidogrel and aspirin vs no anticoagulation). At 150 days, we observed 223 ± 200 mg of thrombus for the no anticoagulation group and 4 ± 4 mg for the aspirin and clopidogrel group (P = .02). Mean platelet deposition on the valve was 4.1 × 109 ± 3.6 × 109 for the no anticoagulation and 6.81 × 107 ± 1.4 × 108 for the combined aspirin and clopidogrel groups, respectively (P = .03). No major hemorrhagic events were observed. Conclusions: Effective short- and long-term thromboprophylaxis of mechanical valves can be achieved by using dual-antiplatelet therapy in this porcine model. Prospective human trials should be conducted with combination aspirin and clopidogrel as an alternative to warfarin in patients with bileaflet mechanical aortic valves. [Copyright &y& Elsevier]

Objectives: Bicuspid aortic valve is a common condition and is associated with a significantly increased risk of developing thoracic aortic aneurysms and acute aortic dissection. Patient-specific prediction of the risk of developing thoracic aortic aneurysm, however, is imprecise. We hypothesize that genotypic variations in patients with bicuspid aortic valves contribute to this observed variability in aortic phenotype. We, therefore, investigated the potential relationship between mutations in regions of NOTCH1 recently reported to be associated with bicuspid aortic valve and the phenotype of bicuspid aortic valve and thoracic aortic aneurysms in unrelated patients undergoing surgical repair. Methods: We performed a targeted mutational analysis of NOTCH1 using genomic DNA from 48 unrelated subjects with concomitant bicuspid aortic valve and thoracic aortic aneurysm using denaturing high-performance liquid chromatography and DNA sequencing. We focused on exons in which mutations associated with bicuspid aortic valve have been reported previously. Results were compared with control subjects with trileaflet aortic valves (n = 94), bicuspid aortic valves, and normal aortas (n = 22) and in subjects with tricuspid aortic valves and thoracic aortic aneurysms (n = 28). Results: Four unique, nonsynonymous (3 novel) variants were identified in 5 (10.4%) of 48 patients with concomitant bicuspid aortic valves and thoracic aortic aneurysms compared with only 3 (2.1%) of 144 control subjects (P = .02). Of these, 2 novel missense mutations, A1343V and P1390T, were observed only in patients with bicuspid aortic valves and tricuspid aortic aneurysms. Conclusions: This targeted analysis involving NOTCH1 exons previously implicated in familial and sporadic bicuspid aortic valve demonstrates overrepresentation of NOTCH1 missense variants among patients with bicuspid aortic valves and thoracic aortic aneurysms. Identification of aneurysm-predisposing susceptibility genes may lead to gene-directed surgical therapy of the ascending aorta for patients with bicuspid aortic valves. [Copyright &y& Elsevier]

Objective: Extra-anatomic bypass of complex thoracic aortic disease through a median sternotomy has been reported as a safe alternative to thoracotomy. Our objective was to examine intermediate-term outcomes. Methods: We retrospectively reviewed 50 consecutive patients with congenital aortic coarctation or recurrent coarctation who underwent ascending–descending posterior pericardial aortic bypass between January 1985 and November 2005. Demographic data, in-hospital and postoperative morbidity and mortality, and resolution of hypertension were determined by examination of the medical record. Results: The mean age at operation was 42 years; 27 (54%) were men. There were no perioperative deaths. Upper-extremity blood pressure after coarctation repair with ascending–descending aortic bypass was significantly improved. Mean systolic blood pressure decreased from 158 ± 25 mm Hg preoperatively to 123 ± 14 mm Hg postoperatively (P < .001). There were no graft-related deaths or complications in follow-up extending up to 20 years. Conclusions: The ascending–descending aortic bypass through a posterior pericardial approach is a safe operation and is effective in relieving obstruction and improving hypertension. [Copyright &y& Elsevier]

Systemic allergic reactions to nickel alloys in percutaneous atrial septal defect occlusion devices have a poorly defined natural history. We describe our experience of surgical removal of the offending device in a series of patients with nickel allergy and refractory symptoms. Patients with atrial septal defect device explants for nickel allergy were reviewed. Administered questionnaires focused on symptoms, quality of life, and satisfaction along with the 36-Item Short Form Health Survey to measure physical and mental health postsurgery. Atrial septal defect devices were removed for nickel allergy in 58 patients during the past 10 years. The median age was 42 years (range, 24-71 years) and 95% were women. Explantation occurred at a median of 8 years (range, 6 months-18 years) after insertion. Symptoms included fatigue (82%), chest pain (78%), headache (73%), and palpitation (58%). Surveys were available for 45 patients: 58% rated their quality of life as poor and 69% were not at all satisfied with their device. Postexplant, all patients reported improvement in their symptoms, with 18 patients (42%) noting complete resolution. In 12 patients prospectively studied, the preoperative scores in physical and mental health domains were lower than the validation group, indicating significant disability. Similarly, there was marked improvement in each domain postremoval. Patients with nickel allergy and severe refractory symptoms after atrial septal defect device implantation experience profound resolution of symptoms and improved quality of life after removal. Nickel allergy should be considered before device insertion, and a low threshold should exist for surgical removal for refractory symptoms. [ABSTRACT FROM AUTHOR]

Abstract Objective The objective of this study was to determine if the implementation of a value-driven outcomes tool comprising modifiable quality and utilization metrics lowers cost and improves value of coronary artery bypass grafting (CABG) postoperative care. Methods Ten metrics were defined for CABG patients in 2 temporally separated phases. Clinical care protocols were designed and implemented to increase compliance with these metrics. Clinical outcomes and cost data were harvested from the electronic medical record using a proprietary value-driven outcomes tool and verified by a data management team. "Perfect care" was defined as achieving all 10 metrics per patient episode. Results Over a 45-month period, data of 467 consecutive patients who underwent isolated CABG were analyzed. "Perfect care" was successfully achieved in 304 patients (65.1%). There were no observed differences in mortality between patient groups. Linear regression analysis showed a negative correlation between percent compliance with "perfect care" and mean cost. When multivariate analysis was used to adjust for preoperative risk score, mean cost for patients with "perfect care" was 37.0% less than for those without "perfect care." Conclusions In the context of focused institution-specific interventions to target quality and utilization metrics for CABG care, clinical care pathways and protocols informed by innovative tools that link automated tracking of these metrics to cost data might simultaneously promote quality and decrease costs, thereby enhancing value. This descriptive study provides preliminary support for a systematic approach to define, measure, and modulate the drivers of value for cardiothoracic surgery patients. [ABSTRACT FROM AUTHOR]

Background Right ventricular (RV) failure (RVF) is a vexing problem facing patients with various disease processes and carries a high mortality. RVF is a poorly understood phenomenon with limited treatment options. In mammalian fetal circulation, the right ventricle is the systemic ventricle. In neonates, however, the left ventricle assumes that role and gradually thickens compared with the right ventricle. This process, known as right ventricular involution (RVI), is poorly understood. We sought to define the time course and identify mechanisms involved in RVI. Methods Wild-type mice were bred and sacrificed on day of life (DOL) 1, 4, 8, 16, and 30 to evaluate left ventricular (LV) and RV wall thickness and apoptosis. A terminal deoxynucleotidyl transferase nick-end labeling assay and RNA sequencing were performed to measure changes during RVI. Results Morphometric analysis demonstrated the changes in RV and LV wall thickness occurring between DOL 1 and DOL 16 (RV:LV, 0.53:0.44; P = .03). In addition, apoptosis was most active early, with the highest percentage of apoptotic cells on DOL 1 (1.0%) and a significant decrease by DOL 30 (0.23%) ( P = .02). Similarly, expression of the proapoptotic genes BCL2l11 and Pawr were increased at DOL 1, and the antiapoptotic genes Nol3 and Naip2 were significantly increased at DOL 30. Conclusions RVI is a misnomer, but significant changes occur early (by DOL 16) in neonatal mouse hearts. Apoptosis plays a role in RVI, but whether manipulation of apoptotic pathways can prevent or reverse RVI is unknown and warrants further investigation. [ABSTRACT FROM AUTHOR]

Objective: The HeartMate II (Thoratec Corp, Pleasanton, Calif) continuous-flow left ventricular assist device has emerged as the standard of care for patients with advanced heart failure. The objective of this study was to assess the safety and early effectiveness of concomitant tricuspid valve procedures in patients undergoing implantation of a HeartMate II device. Methods: From February 2007 to April 2010, 83 patients underwent HeartMate II left ventricular assist device implantation. Of these, 37 patients had concomitant tricuspid valve procedures (32 repairs, 5 replacements) for severe tricuspid regurgitation. The effects of a tricuspid valve procedure on tricuspid regurgitation and right ventricular remodeling were assessed comparing echocardiographic findings at baseline and 30 days after left ventricular assist device implantation. Overall survival was also compared. Results: Patients undergoing a concomitant tricuspid valve procedure had more tricuspid regurgitation (vena contracta, 5.6 ± 2.1 mm vs 2.9 ± 2.0 mm; P < .001), worse right ventricular dysfunction (right ventricular end-diastolic area, 33.6 ± 6.2 mm vs 31.6 ± 8.5 mm; P = .05), higher mean right atrial pressure (17.4 ± 7.1 mm Hg vs 14.9 ± 5.1 mm Hg; P = .03), and a higher Kormos score (2.6 ± 2.1 vs 1.2 ± 1.4; P = .0008) preoperatively. One month after surgery, tricuspid regurgitation was worse in patients who underwent left ventricular assist device implantation alone (+18.6%), whereas it improved significantly in patients undergoing a concomitant tricuspid valve procedure (−50.2%) (P = .005). A corresponding significant reduction in right ventricular end-diastolic area (33.6% ± 6.2% vs 30.1% ± 9.7%; P = .03) and a trend toward better right ventricular function (55.5% ± 79.7% vs 35.7% ± 60.5%; P = .28) were noted in patients undergoing a concomitant tricuspid valve procedure. Survival was comparable between the 2 groups. Conclusions: In patients with severe tricuspid regurgitation undergoing left ventricular assist device implantation, a concomitant tricuspid valve procedure effectively reduces tricuspid regurgitation and promotes reverse remodeling of the right ventricle. [Copyright &y& Elsevier]