Implantable Cardioverter Defibrillators in Patients with Valvular Cardiomyopathy

Sudden Death Prevention in Valvular Cardiomyopathy. Background: Implantable cardioverter‐defibrillators (ICDs) are beneficial for preventing sudden cardiac death (SCD) in patients with previous SCD or left ventricular dysfunction. Objective: The objective was to investigate the outcomes of ICD implantation in patients who have surgery for valvular cardiomyopathy (VCM). Methods: We identified patients with VCM who had ICD implantation after valve surgery. Age‐ and sex‐matched patients who received an ICD for ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM) served as controls. Patients with VCM who had valve surgery but did not receive an ICD served as an additional control group. We compared mortality and appropriate ICD discharges between the study group and control groups. Results: Mean (SD) age (31 patients with VCM with ICD, 30 with ICM, 26 with DCM, and 62 patients with VCM without ICD) was 60 (15) years, 73% were men. Ejection fraction at ICD implantation was 34%, 26%, and 23% for the VCM with ICD, ICM, and DCM groups, respectively (P = 0.03). After a median follow‐up of 4.1 years, survival was not significantly different among ICD groups (P = 0.06). The annual appropriate shock rate was 5%, 10%, and 4% for the VCM with ICD, ICM, and DCM groups, respectively (P = 0.71). Compared to VCM without ICD, patients with VCM and ICD had comparable survival (P = 0.82) despite a reduced LVEF following valve surgery. Conclusion: Patients with VCM who undergo ICD implantation for SCD prevention have similar appropriate ICD discharge rates and mortality as do those with ICM and DCM. These data are hypothesis generating and deserve confirmation with large‐scale prospective studies. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1326‐1332, December 2012)     

Atrioventricular Canal Defects: Results of Repair in the Current Era

Between December 1986 and December 1990, 37 consecutive patients underwent repair of complete atrioventricular (AV) canal with the two-patch technique. Mean age at repair was 22 months and 51% were less than 1 year of age. Eighteen (48.6%) had undergone previous palliative operations. Two operative deaths (5.4%) occurred and another patient died in-hospital for an early mortality of 8.1%. One late death (2.9%) has occurred from a respiratory infection. Actuarial survival is 87.7% at 3 years. Small size (p less than 0.05), unbalanced ventricular size (p less than 0.05), New York Heart Association (NYHA) Class IV (p less than 0.05), and severe preoperative AV valve insufficiency (p less than 0.05) were significant preoperative risk factors for death. Five survivors (14.7%) required reoperation for severe AV valve insufficiency (two) or patch leaks (three). The risk for reoperation was increased in non-Down's patients (p less than 0.02). All survivors are in NYHA Class I (93%) or II (7%). The risk for early AV valve insufficiency was increased in patients who did not have the cleft sutured (p less than 0.05), and in those with unbalanced ventricles (p less than 0.01). Risk of late AV valve insufficiency was increased only by small size (p less than 0.02). Previous pulmonary artery banding did not increase the risk of repair or of postoperative AV valve insufficiency. Complete AV canal can be repaired with low mortality. Pulmonary artery banding may still have a role to play in the very small (4-5 kg) infant in refractory heart failure.     

The effect of a nutritional model of chronic liver injury on the hepatic glucuronidation of morphine in rats

Abstract— The effect of a choline-deficient diet on the hepatic glucuronidation of morphine was investigated using a rat perfused liver system. Rats fed a choline-deficient diet developed a fatty liver with minimal necrosis. Despite the morphological changes, neither hepatic extraction ratio (0·51 ± 0·02 incontrol; 0·45 ± 0·04 in the choline-deficient rats) nor intrinsic clearance (0·85 ± 0·05 in control; 0·77 ± 0·09 in choline-deficient rats) were affected by this injury model. This finding suggests that glucuronidation is relatively resistant to this chronic liver injury.     

The Conduction System Findings in Sudden Cardiac Death

Conduction System in Sudden Death. This is a brief review of the findings in the conduction system in cases of sudden death victims who were living "normal" active lives. Twenty–two representative samples from more than 100 cases of sudden cardiac death, especially in young and asymptomatic individuals, revealed a plethora of findings that varied from normal to congenital and acquired changes, in most cases either at the gross or microscopic level, especially in the conduction system to a varying degree. Despite these changes, the individuals were living normal, symptom–free lives and were not clinically diagnosed to have lethal cardiac problems. This suggests that these individuals might have experienced lethal arrhythmias in the past, which might have been "silent" in nature. Innovative new methodologies must be developed to detect the silent lethal arrhythmic focus that may lead to sudden cardiac death.