川合 真由美

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.

Background: Atrial fibrillation (AF) and heart failure (HF) are associated with significant mortality and morbidity. We sometimes encounter patients who have AF upon admission to the hospital, but it spontaneously converts to sinus rhythm within several days (i.e. converter). Purpose: We examined the association between the outcome and types of strategy for AF treatment in converters. Methods: From January 2000 to December 2005, we identified 95 converters (age 69 +/- 12 years) presenting with worsening HF and AF upon admission, in which sinus rhythm was restored within 7 days without either electrical or pharmacological cardioversion. The patients were classified into three groups according to the antiarrhythmic drug (AAD) therapy used: class I AAD, class III AAD, and rate-control drug. The patients were followed for 36 +/- 23 months. Results: The left ventricular ejection fraction (LVEF) significantly improved with conversion to sinus rhythm (38 +/- 14% vs. 47 +/- 13%, p < 0.05). Those receiving class I AAD had a trend toward a well-preserved LVEF (50 +/- 13%, n = 35) as compared to those receiving class III AAD (43 +/- 12%, n = 24) or rate-control drug (47 +/- 14%, n = 36). In the patients receiving class I AAD, the rate of all-cause death increased 1.9-fold (p = 0.009) compared to those receiving class III AAD, and 1.7-fold (p = 0.010) compared to those taking rate-control drug. A hospitalization for HF was observed in 49 (52%) patients, however there was no significant difference in the rate of hospitalization among the three groups (p = 0.890). Those receiving rate-control drugs had a 50% lower rate of the development of persistent AF than those taking class III AAD (p = 0.019). Conclusions: A rate-control strategy should be the primary approach for converters to reduce mortality and development of persistent AF. (c) 2012 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Aims Increased temporal repolarization lability, assessed by beat-to-beat variability of T-wave amplitude (TAV), has been shown to be associated with ventricular tachyarrhythmia in patients with a variety of clinical conditions. The aim of this study was to test the ability of TAV to identify patients presenting with malignant ventricular arrhythmia and to predict subsequent occurrences. Methods and results We studied 20 consecutive patients (age 42 +/- 15 years, mean +/- standard deviation) presenting with ventricular tachyarrhythmia who did not have substantial underlying heart disease and compared them with 40 age-and sex-matched control subjects. The TAV was determined by Holter recording (Ela Medical). Patients with ventricular tachyarrhythmia had a higher maximum value of TAV (max TAV: 38 +/- 18 vs. 22 +/- 15 mu V, P < 0.001) than did the controls. The sensitivity and specificity of max TAV > 22.4 mu V for detecting the occurrence of ventricular tachyarrhythmia were 77 and 90%, respectively. During a mean follow-up period of 23 months, three patients had relapses of ventricular tachyarrhythmia. Patients with a recurrence of ventricular tachyarrhythmia had a trend towards a higher wmax TAV as compared with those who had ventricular tachyarrhythmia but did not relapse (56 +/- 23 vs. 36 +/- 16 mu V, P = 0.061). Conclusion Our results suggest that Holter-derived TAV might be associated with the occurrence and recurrence of ventricular tachyarrhythmia in patients without structural heart disease. Prospective validation will be necessary to assess the potential diagnostic value of the TAV in a large general population.

Background: n-3 polyunsaturated fatty acids, primarily eicosapentaenoic acid (EPA), has been reported to have antiarrhythmic and antiinflammatory effects. The aim of the present study was to examine whether the combination of antiarrhythmic drugs and EPA reduced the frequency of atrial fibrillation (AF) in patients with paroxysmal AF. Methods: We studied 50 patients with paroxysmal AF (age, 54 +/- 9 years) after excluding the clinical conditions associated with an increased risk of AF. Patients were initially treated with antiarrhythmic drugs for 6 months (the observation period), and thereafter, EPA was added at a dose of 1.8 g/day for 6 months (the intervention period). During a one-year period, patients obtained an ECG recording using a portable device each morning and when arrhythmia-related symptom occurred. The end point was the difference of the AF burden (defined by the days of AF per month) between observation period and intervention period. Plasma EPA and C-reactive protein (CRP) levels were also determined. Results: There was no significant difference in the AF burden before and after intervention (2.6 +/- 2.2 days/months vs. 2.5 +/- 2.2 days/months, P = 0.45). Although EPA level was significantly increased (42 +/- 15 mu g/mL to 120 +/- 47 mu g/mL, P < 0.001), CRP level was unchanged (1.04 +/- 0.69 mg/L to 0.96 +/- 0.56 mg/L, P = 0.24) following EPA treatment. Conclusions: Treatment of EPA in combination with antiarrhythmic drugs did not reduce the AF burden or the CRP levels in paroxysmal AF patients who had no evidence of substantial structural heart disease. Ann Noninvasive Electrocardiol 2011; 16(4): 373-378

Background: Prolonged duration of the QRS complex is a prognostic marker in patients with heart failure (HF), whereas electrocadiographic markers in HF with narrow QRS complex remain unclear. We evaluated the prognostic value of the T-wave amplitude in lead aVR in HF patients with narrow QRS complexes. Methods: We examined 331 patients who were admitted to our hospital for worsening HF (68 +/- 15 years, mean +/- standard deviation) from January 2000 to October 2004 who had sinus rhythm and QRS complex <120 ms. The patients were categorized into three groups according to the peak T-wave amplitude from baseline in lead aVR: negative (<-0.1 mV; n = 209, 63%), flat (-0.1-0.1 mV; n = 64, 19%), and positive (> 0.1 mV; n = 58, 18%). Results: During a mean follow-up of 33 months, 113 (34%) patients had all-cause death, the primary end point. After adjusting for clinical covariates, flat T wave (hazard ratio [HR] 1.86, 95% confidence interval [CI] 1.42-2.46), and positive T wave (HR 6.76, 95% CI 3.92-11.8) were independent predictors of mortality, when negative T wave was considered a reference. Conclusions: As the peak T-wave amplitude in lead aVR becomes less negative, there was a progressive increase in mortality. The T wave in lead aVR provides prognostic information for risk stratification in HF patients with narrow QRS complexes. Ann Noninvasive Electrocardiol 2011; 16(3): 250-257