Origin Of Cardiomyopathy Research Articles

Abstract 17496: The Effect of Statin on Ventricular Tachyarrhythmia Burden

Introduction: Statins may reduce risk for ventricular tachyarrhythmia (VTA) in patients with implantable cardioverter defibrillator (ICD). Ranolazine was shown to increase plasma concentrations of statin. Objective: To evaluate the effect of statin on recurrent VTA, and to explore the interaction with both Ranolizine and cardiomyopathy (CMP) origin. Methods: The Andersen-Gill extension of the Cox proportional hazards regression was used to assess the association between statin treatment and the risk for recurrent VTA among 1012 ICD patients enrolled in the Ranolazine Implantable Cardioverter-Defibrillator Trial (RAID). Interaction-term analysis with ranolazine and ischemic status were performed. Number of events was limited to a maximum of 10 VTA events per patient to avoid any patients having an undue influence on model estimates. Results: A total of 740 (73%) RAID patients were treated with statins. Multivariable analysis showed that statin use was associated with an overall 30% reduction in the risk for recurrent VTA (HR=0.70; p<0.001)(Figure). Interaction analysis showed that the benefit of statin use was seen only among patients with non-ischemic CMP (HR=0.53 [95%CI 0.41-0.69]; p<0.001), whereas there was no evidence of benefit among patients with ischemic CMP for recurrent VTA (HR=1.03 [95%CI 0.70-1.54] p=0.70), with an interaction p-value of <0.01 for the differential effect of statin use on recurrent VTA by CMP origin. The effect of statin was relatively consistent and did not differ significantly between the ranolazine and placebo arms (Figure). Statin use was not associated with increased adverse events, and ranolazine discontinuation was higher among those who were not treated with statins vs. those who received statin therapy (53% vs 42%, respectively; p<0.01). Conclusion: Our findings suggest that treatment with statin (regardless if with or without ranolazine) is highly effective in reducing VTA burden in non-ischemic ICD recipients.

Usefulness and Consequences of Cardiac Resynchronization Therapy in Dialysis-Dependent Patients With Heart Failure

Cardiac resynchronization therapy (CRT) is often deferred in dialysis-dependent patients with heart failure (HF) because of a perceived lack of benefit and potentially higher risks, although the outcomes associated with CRT in dialysis have not been reported. We therefore studied our center's experience with CRT in dialysis-dependent patients. We constructed a descriptive assessment of these patients (n = 15) and performed a case-control analysis matching for age, gender, bundle branch morphology, diabetes mellitus, cardiomyopathy origin, and β-blocker and angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker use. Baseline and 6-month echocardiograms were assessed for evidence of reverse remodeling. No periprocedural or long-term complications were observed among dialysis patients. Heterogenous improvement in ejection fraction (+3.1 ± 9.2%) was noted and 2 patients derived absolute improvements of 8% and 22%, respectively. Dialysis patients demonstrated the following 3-year event rates: HF hospitalization, 31%; all-cause hospitalization, 100%; mortality, 73%; and HF hospitalization or death, 82%. In the case-control analysis, controls demonstrated superior reverse remodeling (+9.2 ± 9.5% increase in ejection fraction), decreased mortality (73% vs 44%, p = 0.038), and all-cause hospitalizations (76% vs 100%, p = 0.047), with no difference in HF hospitalizations (p = 0.39), compared with dialysis patients. In conclusion, at our center, the dialysis-dependent patients with HF who underwent CRT implantation did so safely and no serious complications were observed. Certain dialysis patients demonstrated compelling improvement after device implantation. Compared with matched controls, dialysis patients were at increased risk for adverse events and worsened echocardiographic outcomes.

Early experience with partial left ventriculectomy in the Asia-Pacific region

Background. We report our early experience with partial left ventriculectomy done by a group of cardiac surgeons in the Asia-Pacific region. Methods. Partial left ventriculectomy was done in 48 patients (mean age, 43 years) with advanced symptomatic cardiomyopathy. The origin of cardiomyopathy was idiopathic in 30 patients, valvular in 10, ischemic in 3, peripartum in 3, sarcoidosis in 1, and viral myocarditis in 1. Procedures performed on the mitral valve were repair with Alfieri method in 8 patients, ring annuloplasty in 2, and replacement in 25. Results. Seventy-seven percent of patients required myocardial support for weaning from cardiopulmonary bypass, and the overall in-hospital mortality rate was 27%. Mean follow up was 6.5 months (range, 1 to 18 months), and patient survival at 1, 3, and 6 months after discharge was 91%, 88%, and 84%, respectively. Sixty-five percent of survivors with idiopathic and valvular disease achieved significant and sustained improvement in ventricular contractility and symptoms, but there were no clear symptomatic benefits from partial left ventriculectomy in patients with cardiomyopathy from other causes. Most cases of late recurrence of heart failure symptoms (90%) appeared to be related to the development of progressive mitral incompetence. Conclusions. After partial left ventriculectomy left ventricular function improved in patients with idiopathic and valve related cardiomyopathies. Late deterioration was related to the development of significant mitral valve incompetence postoperatively, hence definitive mitral valve repair or replacement at the time of the partial left ventriculectomy procedure is advised.