The move follows the US Food and Drug Administration's revocation of bevacizumab's use for metastatic breast cancer.
The research team, led by Dr. Toni K Choueiri, assessed findings from five clinical trials involving 3,784 patients with metastatic breast cancer. The trials were conducted between 1966 and March 2010. The trials omitted patients with uncontrolled high blood pressure, clinically significant congestive heart failure, cerebrovascular disease, peripheral vascular disease and unstable angina (constrictive chest pain due to lack of oxygenated blood flow to the heart). Patients who had undergone anthracycline therapy (a type of cancer drug) were included in the trials.
The study found that of the 2,366 patients who had received bevacizumab therapy, 36 had high-grade congestive heart failure, whereas among the 1,418 control patients, four had congestive heart failure (CHF) for incident rates of 1.6 percent and .4 percent, respectively.
The study authors said their report marks the first large-scale study to show a significant increase in the risk of congestive heart failure in bevacizumab-treated patients with metastatic breast cancer.
A recent editorial highlights limitations of the study, however, citing prior anthracycline use among patients ranging from 30 percent of patients to 100 percent in some of the trials.
Dr. Sandra M Swain of the Washington Hospital Center, DC said in the editorial that patients with previous anthracycline use could have had damaged hearts that contributed to their heart failure. Swain also listed a series of conditions in the editorial that could also contribute to CHF, which the study's authors did not include. These include: radiation, heart-disease history and diabetes, among others.
Swain said there are other ways in which bevacizumab could be cardiotoxic, however. There are a number of preclinical and physiologic reasons for developing heart failure, she wrote, and accounted the effect of bevacizumab following a drug like doxorubicin, which affects the heart. That may leave a patient with a limited ability to repair injury and lead to heart failure, she wrote.
Congestive heart failure, usually a chronic condition, occurs when the heart can no longer pump enough blood to supply organs and the rest of the body. It may affect only one side of the heart or both. Coronary artery disease is the most common cause of heart failure in the U.S., but the condition may also follow certain illnesses or poisoning that weakens the heart muscle.
Symptoms of heart failure include shortness of breath with activity or while lying down, swelling in the abdomen, irregular or rapid pulse and fatigue.