Dipyridamole in heart failure due to dilated cardiomyopathy: A pilot study

Abstract

Introduction: Dipyridamole (DIP) might be beneficial in heart failure (HF). It has been reported to improve symptoms in observational, small‑scale studies. The PRoFESS study for secondary prevention of stroke observed a reduction in the risk of HF with acetylsalicylic acid (ASA) plus DIP in comparison with clopidogrel. The present pilot study was aimed at assessing the clinical effects of DIP and ASA in dilated cardiomyopathy. Materials and Methods: Nineteen outpatients with nonischemic HF, New York Heart Association (NYHA) Class II, ejection fraction (EF) <40%, were randomized to ASA 25 mg, or ASA 25 mg plus DIP 200 mg (ASA + DIP), twice daily. They were evaluated at baseline and after 6 months for symptoms, EF, and exercise capacity through 6‑min walk test. Results: Eleven subjects were in the ASA group and 8 in the ASA + DIP. Dyspnea improved, without differences between the two arms: n = 6/5/0/0 for NYHA I/II/III/IV in ASA, n = 4/3/1/0 in ASA + DIP. EF increased in both groups (ASA: from 34 [28–35%] to 40 [32–46%]; ASA + DIP from 32.5 [25.75–34%] to 36 [31.5–46%]). No change in meters walked or points in the Borg scale was observed. In a similar population, an adequately powered study would need to recruit 38 subjects. Conclusion: The study, although underpowered, did not show any difference between the two treatment strategies. While this appears in contrast with previous studies, the strict inclusion criteria, the randomized, double‑blind design, and the clinical end‑points give strength to our findings. A properly sized trial would be within the capabilities of a single center.