Complementary and alternative medicine in cardiovascular disease: a review of biologically based approaches

The use of complementary and alternative medical (CAM) practices in the United States is growing rapidly. In this manuscript, we review some of the most commonly used biologically based approaches, including herbs, supplements, and other pharmacological therapies, that are encountered in caring for patients with cardiovascular disease, focusing on potential effects, adverse effects, and treatment interactions.

Between November 2002 and April 2003, we searched Medline and the National Center for Complementary and Alternative Medicine (NCCAM) web site and its various references and several complementary medicine text books. The key words used were: "cardiovascular diseases," "coronary disease," "heart failure, congestive," "complementary and alternative medicine," "complementary therapies," "drug interactions," and "plants, medicinal." A keyword search of each individual supplement identified was also performed. Additionally, we relied on expert opinion in the field.

Potentially serious adverse effects and interactions with conventional cardiovascular therapies exist for many herbs and supplements. There are currently scarce mechanistic data and very limited data on the effect of CAM therapies on clinical outcomes.

Randomized clinical trials with adequate power to detect effects of CAM therapies on clinical outcomes and safety are needed. Until these data are available, clinicians must be aware of the increasing use of CAM approaches by their patients and the potential for interactions with conventional therapies and should focus on treatment with proven, evidence-based strategies.