ABSTRACT
BACKGROUND: Chronic heart failure (CHF) is associated with a high risk of sudden cardiac death (SCD). Most frequently SCD occurs in patients with NYHA class II and III. AIM: To evaluate the influence of prolonged carvedilol therapy on SCD risk in CHF patients. METHODS: The study included 86 patients (81 men and 5 women) aged 56.8+/-9.19 (35-70) years with CHF in NYHA class II and III receiving an ACE inhibitor and diuretics but not beta-blockers. At baseline and after 12 months of carvedilol therapy the following risk factors for SCD were analysed: in angiography - occluded infarct-related artery; in echocardiography - left ventricular ejection fraction (LVEF) <30%, volume of the left ventricle (LVEDV) >140 ml; in ECG at rest - sinus heart rate (HRs) >75/min, sustained atrial fibrillation, increased QTc; in 24-hour ECG recording - complex arrhythmia, blunted heart rate variability (SDNN <100 ms) and abnormal turbulence parameters (TO and TS or one of them); in signal-averaged ECG - late ventricular potentials and prolonged fQRS >114 ms. The analysis of SCD risk factors in basic examination in patients who suddenly died was also performed. RESULTS: During one-year carvedilol therapy heart transplantation was performed in 2 patients; 5 patients died. At 12 months the following risk factors for SCD were significantly changed: HRs >75/min (50 vs. 16 patients, p=0.006), LVEF <30% (37 vs. 14 patients, p=0.01), SDNN <100 ms (19 vs. 9 patients, p=0.04). At 12 months the number of risk factors for SCD in each patient was significantly reduced (p=0.001). In patients who suddenly died we found a greater amount of SCD risk factors in basic examination (7 vs. 5) as compared to alive patients. CONCLUSIONS: Prolonged beta-adrenergic blockade reduces risk of sudden cardiac death through significant LVEF increase, reduction of HR at rest and improvement of HRV.
Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Carbazoles/therapeutic use , Death, Sudden, Cardiac/etiology , Heart Failure/complications , Heart Failure/drug therapy , Propanolamines/therapeutic use , Adult , Aged , Carvedilol , Female , Heart Rate , Humans , Male , Middle Aged , Risk Factors , Severity of Illness Index , Stroke Volume , Treatment OutcomeABSTRACT
BACKGROUND: Electrocardiographic lead aVR is usually ignored in patients with chest pain. ST segment elevation in aVR may have diagnostic value in patients with acute coronary syndrome (ACS) and significant stenosis or obstruction of the left main coronary artery (LMCAS), especially when accompanied by ST segment elevation in lead V(1). AIM: To asses the value of lead aVR and V1 for the detection of LMCAS in patients with ACS. METHODS: The study group consisted of 150 patients (mean age 60.6+/-9.5 years, range 33-78 years) with ACS, including 46 with LMCAS and 104 without LMCAS. ECG recordings obtained on admission were compared between these two groups. RESULTS: In patients with LMCAS, ST segment elevation in lead aVR was two times more frequent than in remaining patients (69.6% vs 34.6% p=0.0001) whereas there were no differences in lead V(1). Sensitivity of ST elevation in aVR in detection of LMCAS was 69.6%, specificity - 65.4%, positive predictive value - 47.1%, and negative predictive value - 82.9%. In patients with LMCAS, ST segment depression was significantly more often present in ECG leads other than aVR (45.6% vs 23.1% p<0.01). Patients with LMCAS more often had hypertension (95.6% vs 77.9% p<0.05) and three-vessel disease (78.3% vs 31.8%, p<0.0001). CONCLUSIONS: The assessment of lead aVR in patients with ACS may indicate LMCAS. Additional analysis of lead V(1) does not improve diagnostic accuracy.
