Physiological Effects of Grape Seed Extract in Diastolic Heart Failure

Summary

Diastolic heart failure (also known as "heart failure with normal ejection fraction" or "heart failure with preserved ejection fraction") occurs even though the heart muscle's pumping function is normal. In many cases diastolic heart failure is related to stiffening of the heart and blood vessels in people who have high blood pressure. Current guidelines suggest that patients should limit the salt content of their diet, as too much salty food can cause fluid retention and other problems in diastolic heart failure. Studies in animals with diastolic heart failure suggest that antioxidant chemicals found in grapes can block some of the harmful effects of salty diets. Because it is often difficult for patients with diastolic heart failure to maintain a low salt diet, the investigators are researching the effects of the antioxidant properties of grape seed extract, a natural supplement made from grape seeds. The investigators hypothesize that supplementing the diet with grape seed extract (GSE) can decrease the levels of harmful chemicals and improve heart and blood vessel function in patients with diastolic heart failure and a history of high blood pressure. The University of Michigan research group plans to enroll 25 patients with a history of high blood pressure and diastolic heart failure in a research study. The study will assess the effects of GSE on hormones and other chemicals that can cause heart and blood vessel damage. The investigators will also study the effects of GSE on the ability of the blood vessels and heart muscles to relax at the proper time and speed. Finally, the investigators will observe how GSE affects participants' overall ability to exercise, quality of life, and blood pressure control. Study participants will be randomly assigned to take either GSE or placebo (looks like but does not contain GSE) capsules twice a day for six weeks. After a two-week break, all subjects will cross over to the opposite group of capsules for an additional six-week period. At the start of the study and at the end of each six-week time period study participants will have non-invasive heart and blood vessel testing, blood work and urine tests, and blood pressure monitoring.

Timeline

Start

2010-10

Primary completion

2013-11-04

Completion

2014-02-24

Publications

• Background Seymour EM, Singer AA, Bennink MR, Parikh RV, Kirakosyan A, Kaufman PB, Bolling SF. Chronic intake of a phytochemical-enriched diet reduces cardiac fibrosis and diastolic dysfunction caused by prolonged salt-sensitive hypertension. J Gerontol A Biol Sci Med Sci. 2008 Oct;63(10):1034-42. doi: 10.1093/gerona/63.10.1034.
• Background Ma L, Gao HQ, Li BY, Ma YB, You BA, Zhang FL. Grape seed proanthocyanidin extracts inhibit vascular cell adhesion molecule expression induced by advanced glycation end products through activation of peroxisome proliferators-activated receptor gamma. J Cardiovasc Pharmacol. 2007 May;49(5):293-8. doi: 10.1097/FJC.0b013e31803c5616.
• Background Sivaprakasapillai B, Edirisinghe I, Randolph J, Steinberg F, Kappagoda T. Effect of grape seed extract on blood pressure in subjects with the metabolic syndrome. Metabolism. 2009 Dec;58(12):1743-6. doi: 10.1016/j.metabol.2009.05.030. Epub 2009 Jul 15.
• Background Kar P, Laight D, Rooprai HK, Shaw KM, Cummings M. Effects of grape seed extract in Type 2 diabetic subjects at high cardiovascular risk: a double blind randomized placebo controlled trial examining metabolic markers, vascular tone, inflammation, oxidative stress and insulin sensitivity. Diabet Med. 2009 May;26(5):526-31. doi: 10.1111/j.1464-5491.2009.02727.x.

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