In patients with myocardial infarction (MI), anginal attacks, reinfarctions or sudden deaths occur occasionally during or after bathing. Therefore it is important to know well about influence of bathing on cardiac function. In this study we examined hemodynamic indices by means of Swan-Ganz catheter and blood flow pattern with Doppler echocardiographic method in comparison with cardiac events (CE) during and after admission.
Forty-nine patients with MI (mean age 58.9 years) were examined, including 14 patients with extensive anterior MI, 12 with anterior, 17 with inferior and 6 with anterior and inferior MI. Bathing was carried out at supine position in a tap water at 42°C during 5 minutes in the Hubbard tank. The patients was classified into two groups, one with CE (Group A), and the other without CE (Group B). Hemodynamic indices by means of Swan-Ganz catheter, peak velocities of blood flow (PV) at left ventricular outflow tract (LVOT) and blood flow pattern at left ventricular inflow tract (LVIT) with Doppler echocardiographic method were studied in comparisons.
Seven of 49 patients had CE (2 cases with sudden death, 2 cases with reattack of MI and 3 cases with heart failure), and 2 of theses 7 cases had CE during bathing (one with sudden death and the other with reattack of MI). Pulmonary capillary wedge pressure (PCWP) increased from 4.0±2.7mmHg to 12.5±4.6mmHg in Group B, while in Group A marked increases in PCWP on bathing were noted from 3.9±1.2mmHg to 18.1±4.8mmHg (p<0.001) and significant high level was maintained during bathing. Mean pulmonary arterial pressure (mPAP) in Group A also increased during bathing significantly compared with Group B. Six of 13 patients (46.2%) with decreased PV at LVOT and 3 of 8 patients (37.5%) with markedly increased A/R at LVIT on bathing had CE, which was noted at the higher rate compared with those with increased PV and without markedly increased A/R (each, p<0.001, p<0.05). In Group A, severe heart failure on admission into coronary care unit was significantly noted much (p<0.001), physical work capacity was lower in exercise tolerance test by bycyle ergometer and left ventricular ejection fraction was lower (26.9±6.1% vs 56.1±16.6%, p<0.001) with significance in cardiac catheterization, suggesting cardiac dysfunction.
In conclusion, bathing should be carried out carefully in patients with markedly increased PCWP or mPAP, with decreased PV at LVOT and with markedly increased A/R at LVIT.