Sudden cardiac death risk factors in patients with heart failure treated with carvedilol.
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.


OBJECTIVE
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.
Nessler
Jadwiga
J
Klinika Choroby Wieńcowej, Instytut Kardiologii, Collegium Medicum UJ, Kraków. jnessler@interia.pl
Nessler
Bohdan
B
Kitliński
Mariusz
M
Libionka
Anna
A
Kubinyi
Aleksander
A
Konduracka
Ewa
E
Piwowarska
Wiesława
W
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D002227:Carbazoles / Q000627:therapeutic use*; D000077261:Carvedilol; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000188:drug therapy*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011412:Propanolamines / Q000627:therapeutic use*; D012307:Risk Factors; D012720:Severity of Illness Index; D013318:Stroke Volume; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol