[Effects of bathing on cardiac function in patients with myocardial infarction: hemodynamic and Doppler echocardiographic studies].

Hemodynamic changes during bathing in patients with myocardial infarction were studied using a Swan-Ganz catheter and Doppler echocardiography. The subjects consisted of 14 patients with myocardial infarction (mean age 55.6 years), including the six extensive ones of the anterior wall, five of the anteroseptal wall, two of the inferior wall, and one of the inferoposterior wall. Bathing was by means of 42 degrees C tap water for five min in the supine position in a Hubbard tank. Pulsed wave Doppler was used to analyze left and right ventricular inflow velocity patterns, and continuous wave Doppler was employed to measure right ventricular outflow velocity. Blood pressure, pulmonary arterial pressure, pulmonary arterial wedge pressure and right atrial pressure increased significantly during bathing. After bathing, these parameters decreased and remained lower than the baseline levels before bathing. Heart rate and the cardiac index increased significantly during bathing, but decreased after bathing. The systemic vascular resistance index and pulmonary vascular resistance index decreased significantly during bathing, but increased after bathing. The A/R ratio at the left and right ventricular inflow tracts increased during bathing, and right ventricular outflow velocity increased significantly. However, when the subjects were categorized into two groups, i.e., those whose pulmonary arterial pressure consistently increased to the higher level than the average during bathing and those who did not show any increase, the A/R ratio at the inflow tract of the left ventricle increased significantly during bathing in the former group, but there was no significant change in the latter group.(ABSTRACT TRUNCATED AT 250 WORDS)