Sauna-induced myocardial ischemia in patients with coronary artery disease

PURPOSE: Sauna bathing is a popular recreational activity that is generally considered to be safe. However, there have been case reports of adverse ca rdiac events. We sought to determine whether sauna use caused myocardial is chemia in patients with coronary artery disease. METHODS: Sixteen patients with proven coronary artery disease were submitte d to three conditions (rest, exercise, and sauna bathing) with continuous e lectrocardiographic (ECG) monitoring and regular blood pressure measurement s. During each condition, patients were injected with Tc-99 sestamibi follo wed by nuclear scintigraphic imaging. Perfusion defect scores were calculat ed in 15 patients. RESULTS: Sauna bathing was well tolerated. There was a mean (+/- SD) increa se in heart rate of 32% +/- 20% in the sauna (resting mean heart rate = 60 +/- 9 beats per minute vs sauna mean heart rate = 79 +/- 11 beats per minut e, P < 0.001) and a 13% +/- 6% drop in systolic blood pressure (resting mea n systolic blood pressure = 142 +/- 14 mm Hg vs sauna mean systolic blood p ressure = 123 +/- 15 mm Hg, P < 0.001). There were no arrhythmias or ECG ch anges in the sauna. Compared with rest, there was significant ischemia duri ng sauna bathing (average perfusion defect score at rest = -0.44 vs average sauna score = -0.93, P < 0.001). The perfusion defect score in the sauna w as worse than the resting score in 14 of the 15 patients. Sauna-associated perfusion defect scores were highly correlated with exercise-induced scores (R-2 = 0.65, P < 0.001), CONCLUSION: In patients with stable coronary artery disease, sauna use is c linically well tolerated but is associated with scintigraphically demonstra ted myocardial ischemia. (C) 1999 by Excerpta Medica, Inc.