Cardiac arrhythmias in chronic heart failure

It has been proven that treatment of chronic heart failure (CHF) with some modern drugs is able to reduce mortality in groups of patients with the severest grades of this disease. The risk of sudden death has been unchanged, however. Out of 49 patients on long-term follow-up, 28 patients are surviving (group A) and 21 died (group B). 52.3% of the dead patients died suddenly. Eight patients in NYHA classes I-II died, all of them suddenly. Contrary to this, sudden death was the cause of death only in three of 13 patients in NYHA classes III-IV (p < 0.001). More severe heart failure was present in group B (NYHA class 2.95 +/- 0.96 vs. 2.18 +/- 0.48 in group A--p < 0.1). Antiarrhythmic drugs were given more frequently in group B (in 47.6% of pts vs. 17.9% in group A--p < 0.05). It is concluded that the occurrence of sudden death is higher in patients with less severe forms of CHF and has not been reduced by the means employed. Use of antiarrhythmic drugs may be dangerous and their indication should be based on results of a comprehensive examination. Use of the implantable cardioverter-defibrillator seems to be the most promising approach in indicated cases.