Long-term treatment of hypertrophic cardiomyopathy with verapamil or propranolol in matched pairs of patients: Results of a multicenter study

Abstract

The effects of a 2-year treatment with high-dose propranolol (mean, 340 +/- 135 mg/day) and verapamil (mean, 493 +/- 136 mg/day) were compared in two groups of patients with hypertrophic cardiomyopathy. Both groups were broadly identical at the beginning of the trial and were formed of matched pairs. Out of 137 patients entering the study, 37 pairs completed the 2 year follow-up. The mean group symptomatology (NYHA-classification) improved significantly only following verapamil treatment. Individual improvement was seen more often following verapamil (V), but deterioration was almost exclusively seen during propranolol (P) treatment. Reduction of the Sokolow-index was significant in the V group only. Reduction in the resting heart rate and maximum gradient was more pronounced following P. No correlation could be found between the change in clinical symptoms and electrocardiographic, echocardiographic or hemodynamic data, nor to the dosage of V or P administered. From clinical and echocardiographic findings and in respect of side effects, V is advantageous over P in the treatment of hypertrophic cardiomyopathy, although a considerable number of patients improve after P. Objective data do not allow one to anticipate responders or non-responders to either treatment.