狭心症患者の入浴時の心電図変化について　　入浴ホルター心電図による検討

Recently in Japan, cerebro-cardiovascular accidents during bathing have increased in the elderly. By habit most Japanese prefer hot water bathing to lukewarm bathing, and most of them usually bathe without immersion of their head. Bathing Holter Electrocardiographic examinations were performed in 60 patients with angina pectoris.<BR>The subjects were divided into 3 groups ; effort angina (n=28), rest angina (n=16) and effort-rest angina (n=16). Water-proof Holter Electrocardiographic recorders (Marquette) were attached to the subjects from three hours before bathing until about a half an hour after bathing.<BR>Behavior of bathing was arbitrary, but actions of the patient and water temperature of bath-tub were recorded in detail. Analyses were performed by SERIES 8200/T HOLTER ANALYSIS SYSTEM. Significant ischemic ST-T changes and prominent arrhythmias were considered positive on ECG. Positive ECG changes appeared in 7% of the patients with effort angina (2 out of 28), 38% of rest angina (6 out of 16) and 81% of effort-rest angina (13 out of 16). Positive ECG changes in the patients with rest angina occurred in the hot water during bathing and during the standing position immediately after they exited the bath-tub. To the contrary, all positive patients with effort angina and effort-rest angina, had ischemic changes recorded while in the bath-tub. Main cause of these ischemic changes on ECG in the patients with rest angina during bathing was speculated to be coronary spasm that might occur when the blood pressure abruptly dropped when in the standing position during the course of hot water bathing.<BR>In several positive cases of the rest angina, coronary spasms were detected by coronary angiography. The patients with effort angina seemed to get rid of ischemic changes on ECG in the bath-tub in contrast with the patients with effort-rest angina. While the cause of this difference is unclear, patients with effort angina may be able to manage the balance of oxygen demand and supply of the heart while in the bath-tub much more efficiently than the patients with effort-rest angina.<BR>An important observation is that none of the positive patients of angina complained of any chest pain during bathing, so they may be classified as having “Silent Myocardial Ischemia”.