Takashi Kihara, MD; Sadatoshi Biro, MD; Yoshiyuki Ikeda, MD; Tsuyoshi Fukudome, MD; Takuro Shinsato, MD; Akinori Masuda, MD; Masaaki Miyata, MD; Shuichi Hamasaki, MD; Yutaka Otsuji, MD; Shinichi Minagoe, MD; Suminori Akiba, MD*; Chuwa Tei, MD

Background: The aim of the present study was to determine whether repeated 60°C sauna treatment improves cardiac arrhythmias in chronic heart failure (CHF) patients, because ventricular arrhythmias are an important therapeutic target in CHF.

Methods and Results: Thirty patients (59±3 years) with New York Heart Association functional class II or III CHF and at least 200 premature ventricular contractions (PVCs)/24h assessed by 24-h Holter recordings were studied. They were randomized into sauna-treated (n=20) or non-treated (n=10) groups. The sauna-treated group underwent a 2-week program of a daily 60°C far infrared-ray dry sauna for 15min, followed by 30min bed rest with blankets, for 5 days per week. Patients in the non-treated group had bed rest in a temperature-controlled room (24°C) for 45 min. The total numbers of PVCs/24 h in the sauna-treated group decreased compared with the non-treated group [848±415 vs 3,097±1,033/24 h, p<0.01]. Heart rate variability (SDNN, standard deviation of normal-to-normal beat interval) increased [142±10 (n=16) vs 112±11 ms (n=8), p<0.05] and plasma brain natriuretic peptide concentrations decreased [229±54 vs 419±110 pg/ml, p<0.05] in the sauna-treated group compared with the non-treated group.

Conclusion: Repeated sauna treatment improves ventricular arrhythmias in patients with CHF. (Circ J 2004; 68: 1146 –1151)