kawai mayumi

AIMS: We examined whether the severity of central sleep apnoea (CSA) and the level of C-reactive protein are associated with the prevalence and complexity of arrhythmias, and whether these factors contribute to increased risk of nocturnal sudden death. METHODS AND RESULTS: We prospectively examined 178 patients (age 70 ± 1 years) who were admitted to our hospital due to worsening heart failure. We recorded a simultaneous overnight cardiorespiratory polygraph and Holter ECG. Obstructive sleep apnoea was excluded and patients were dichotomized based on the median value of the central apnoea index (CAI) of 7.5/h. The prevalence and complexity of arrhythmias were compared between daytime (06:00 h to 15:00 h) and night-time (21:00 h to 06:00 h). A multivariate logistic regression analysis revealed that the CAI was associated with prevalence of atrial fibrillation (AF) [odds ratio 1.03, 95% confidence interval (CI) 1.02-2.51)] and sinus pause during the night-time period (1.12, 95% CI 1.08-1.35). The CAI and C-reactive protein were independently associated with non-sustained ventricular tachycardia during both daytime (1.22, 95% CI 1.00-6.92; and 5.82, 2.58-56.1, respectively) and night-time periods (3.57, 95% CI 1.06-13.1; and 10.7, 3.30-44.4, respectively). During a mean follow-up period of 22 months, 30 (17%) patients had cardiovascular deaths and the CSA was an independent predictor (hazard ratio 1.29, 95% CI 1.16-2.32); only 5 (2.8%) of them died due to ventricular tachyarrhythmia, occurring during wakefulness. CONCLUSIONS: We demonstrated that the severity of CSA and C-reactive protein levels are independently associated with the prevalence and complexity of arrhythmias. CSA was associated with increased mortality risk, but it was not related directly to nocturnal death due to ventricular tachyarrhythmia.

Cardiac resynchronization therapy (CRT) using biventricular pacemakers offers additive mortality and morbidity benefits beyond medication in patients with severe heart failure. There is a paucity of data regarding the impact of CRT in patients with atrial fibrillation. We therefore determined the differential impact of CRT for patients with atrial fibrillation and sinus rhythm. We analyzed 38 consecutive patients (age 61±11 years, male 58%) who had received CRT between January 2003 and January 2009. Biventricular pacing rate in both sinus rhythm and atrial fibrillation was more than 95%. During a follow-up period of 25 months, 17 (44%) patients died from cardiac causes or were hospitalized for heart failure. There was no significant difference in the endpoint between the patients with sinus rhythm and those with atrial fibrillation (p = 0.87). The echocardiogram revealed that the left ventricular end-systolic volume was significantly reduced 6 months after the CRT and the magnitude of its decrease was significantly correlated with the rate of biventricular pacing (r =−0.42, p<0.01, n = 38). We concluded that there was no significant differential impact of CRT between the patients with atrial fibrillation and those with sinus rhythm.

Lamins belong to the intermediate filament gene super-family, which is the main architectural component of the inner nuclear membrane, and influences gene duplication and expression. Lamin A/C gene (LMNA) mutations cause Emery-Dreifuss muscular dystrophy, which is characterized by a triad including joint contractures, muscle weakness, and abnormalities of the conduction-system, and cardiomyopathy. LMNA has also been detected in patients with progressive conduction-system disease and cardiac dysfunction but without muscular dystrophy, which is called cardiolaminopathy. The majority of cardiolaminopathy patients die due to heart failure or ventricular tachyarrhythmias. We report 3 cases (the average age, 49.6 year-old at the time of the implantation of the cardiac pacemaker, male/female=1/2) with a novel nonsense mutation (Q258X) that received cardiac pacemakers for bradycardia.