Impact of Anemia on Exercise and Pharmacologic Stress Echocardiography.

Background The safety and diagnostic accuracy of stress testing in anemic patients have not been well studied. Despite a lack of data, significant anemia may be considered a relative contraindication to stress testing because of safety concerns related to insufficient myocardial oxygen supply. Methods The authors reviewed 28,829 consecutive patients with blood hemoglobin drawn within 48 hours of stress echocardiography (15,624 exercise and 13,205 dobutamine). The associations of blood hemoglobin concentration with arrhythmia and other stress echocardiographic findings were examined. Additionally, the effect of anemia on the positive predictive value of stress echocardiography for the detection of significant coronary artery stenosis (≥50%) was assessed in patients who subsequently underwent coronary angiography. Results Anemia was present in 6,401 patients (22.2%) and was severe (hemoglobin Conclusions This study demonstrates that stress testing is safe in patients with mild and moderately anemia, albeit with a small increase in mild supraventricular arrhythmias with exercise. However, worsening anemia was associated with a significant reduction in exercise capacity. Additionally, worsening anemia was associated with an improvement in the positive predictive value of stress echocardiography. Extrapolation of these data to patients with severe anemia should be performed with caution given the limited number of patients with severe anemia in this study.