Acute Dietary Nitrate in Dilated Cardiomyopathy

Dietary Nitrate Supplementation in Dilated Cardiomyopathy: An Acute, Double-blind, Randomized, Placebo-controlled, Crossover Trial.

Acute consumption of dietary nitrate (as beetroot juice) has been shown to improve exercise capacity in athletes, healthy adults and subjects with both peripheral vascular disease or COPD. Many patients with dilated cardiomyopathy have reduced exercise capacity, The investigators hypothesized that acute nitrate consumption might increase incremental shuttle walk test (ISWT) distance in dilated cardiomyopathy subjects compared to a placebo beetroot juice.

Acute consumption of dietary nitrate (as beetroot juice) has been shown to improve exercise capacity in athletes, healthy adults and subjects with both peripheral vascular disease or COPD. Many patients with dilated cardiomyopathy have reduced exercise capacity, The investigators hypothesized that acute nitrate consumption might increase incremental shuttle walk test (ISWT) distance in dilated cardiomyopathy subjects compared to a placebo beetroot juice. This study is a randomized, double-blind placebo-controlled, crossover trial. Resting blood pressure, phlebotomy and ISWT will be performed. Following completion, each subject is randomized to consume beetroot juice or placebo. 3 hours later, the same assessments are repeated by the same people. After a 7d washout, the entire protocol is repeated with the crossover beverage.

140ml of nitrate rich beetroot juice provides 12.9mmol nitrate and will be on a single occasion by the study subjects.

140ml of nitrate depleted beetroot juice provides 0.5mmol nitrate and will be on a single occasion by the study subjects.

Inclusion Criteria: Clinically stable, Confirmed non-ischemic, dilated cardiomyopathy Exclusion Criteria: Active musculo-skeletal conditions Ischemic heart disease Pulmonary hypertension COPD Taking vasodilators Diabetes mellitus