Cardiotoxicities of paclitaxel in African Americans

To assess the cardiac disturbances in African-American patients treated with paclitaxel.

One-hundred-nineteen African-American patients received paclitaxel for various cancers at Howard University Hospital during the years 1993-2001. Medical records of 100 patients were available for review. Sixty-seven percent were women and 33% were men. Ages ranged between 26-85 years (mean age 51 years). Medical records were reviewed for demographics, types of cancer, dosage and frequency of paclitaxel and other chemotherapeutic agents, events during paclitaxel infusion, initial and subsequent EKGs, and hospital admissions. We used the Chi-square test to compare EKG changes in patients with and without cardiac risk factors.

Ninety patients received paclitaxel as second-line chemotherapy, and 10 patients were treated with paclitaxel as a single agent. Dosage of paclitaxel ranged from 75-200 mg/square meter and was administered every 1-3 weeks. The electrocardiogram readings revealed the following cardiac events: 26% sinus tachycardia, 13% non-specific T-wave changes, 6% myocardial infarction, 4% prolonged QT interval, 4% left-bundle branch block, 3% right-bundle branch block, 3% sinus bradycardia, 2% premature atrial contractions, 2% premature ventricular contractions, 2% atrial flutter, and 1% atrial fibrillation. Eighty percent of the patients had risk factors for coronary artery disease. These cardiac disturbances were observed from day one to a maximum of eight years after receiving the chemotherapy and were independent of dosage of paclitaxel. Sixty percent of our study population had underlying co-morbid conditions, such as dehydration, anemia, sepsis, and hypoxia. The EKG changes observed in patients with underlying cardiac risk factors were statistically significant (p<0.0001).

Paclitaxel was not associated with significant symptomatic cardiac disturbances during infusion in our study population. Caution should be exercised in patients with underlying cardiac disease and risk factors for coronary artery disease. However more prospective studies with closer follow-up during paclitaxel infusion are needed to assess its cardiotoxicities.