RESUMEN
BACKGROUND: We conducted a prospective multicenter case-control study to confirm the clinical efficacy and safety of Waon therapy on chronic heart failure (CHF). METHODS: Patients (n=188) with CHF were treated with standard therapy for at least 1 week, and then were randomized to Waon therapy (n=112) or a control group (n=76). All patients continued conventional treatment for an additional 2 weeks. The Waon therapy group was treated daily with a far infrared-ray dry sauna at 60 degrees C for 15 min and then kept on bed rest with a blanket for 30 min for 2 weeks. Chest radiography, echocardiography, and plasma levels of brain natriuretic peptide (BNP) were measured before and 2 weeks after treatment. RESULTS: NYHA functional class significantly decreased after 2 weeks of treatment in both groups. Chest radiography also showed a significant decrease of the cardiothoracic ratio in both groups (Waon therapy: 57.2+/-8.0% to 55.2+/-8.0%, p<0.0001; control: 57.0+/-7.7% to 56.0+/-7.1%, p<0.05). Echocardiography demonstrated that left ventricular diastolic dimension (LVDd), left atrial dimension (LAD), and ejection fraction (EF) significantly improved in the Waon therapy group (LVDd: 60.6+/-7.6 to 59.1+/-8.4 mm, p<0.0001; LAD: 45.4+/-9.3 mm to 44.1+/-9.4 mm, p<0.05; EF: 31.6+/-10.4% to 34.6+/-10.6%, p<0.0001), but not in the control group (LVDd: 58.4+/-10.3 mm to 57.9+/-10.4 mm; LAD: 46.3+/-9.7 mm to 46.2+/-10.1 mm; EF: 36.6+/-14.1% to 37.3+/-14.0%). The plasma concentration of BNP significantly decreased with Waon therapy, but not in the control group (Waon: 542+/-508 pg/ml to 394+/-410 pg/ml, p<0.001; control: 440+/-377 pg/ml to 358+/-382 pg/ml). CONCLUSION: Waon therapy is safe, improves clinical symptoms and cardiac function, and decreases cardiac size in CHF patients. Waon therapy is an innovative and promising therapy for patients with CHF.