In order to clarify the causes of sudden death (death within 6 hours after the acute episode), we studied the 1564 consecutive autopsies in the aged. There were 250 cases (14.7% of total autopsied cases) of sudden death. They consisted of 119 males and 111 females. Sudden death from cardiovascular disease was found in 37.8%; cardiac death was 30.4%, and the death due to rupture of aortic aneurysm was 7.4%. Other cases of sudden death were asphyxia (20.8%), pneumonia (10.8%), cerebrovascular disease (6.5%), gastrointestinal disease (5.2%) and others. One hundred and sixteen were diagnosed acurately before death. The percentage of acurate diagnosis was highest in cases who died of gastrointestinal bleeding (83.3%) and the lowest in the cases of the rupture of the aortic aneurysm (35.3%). The major underlying diseases were cardiovascular disease (39.6%), pulmonary disease (22.6%), gastrointestinal disease (16%), cerebrovascular disease (13.5%) and others. Pulmonary diseases were the common underlying disease in cases of asphyxia. The cases, died less than five minutes from the onset of the acute episode, were observed in 56 cases. Of the 56 cases there were 25 cases of cardiovascular diseases and 15 cases of asphyxia. There were 21 cases found after death; 7 of them died of asphyxia and 3 died of pneumonia. It should be noticed that sudden death in the aged was observed in 14.7% and showed multiple causes, atypical or minimun symptomes.
ST segment mapping was performed on 15 patients with ischemic heart disease and 5 control subjects before and after isoproterenol (ISP) infusion. ST mapping was recorded using 87 leads according to Yamada. ISP was injected at a rate of 0.02g/kg/min for 5 minutes. In ischemic heart disease, ST map developed negative areas in the left anterior chest wall extending from mid line to left axillar line after ISP. The ST depression appeared gradually during infusion of ISP and completed by 5 minutes. This distribution of ST depression was different from that of left ventricular hypertrophy, or of complete left bundle branch block which spared mid anterior chest. Typical precordial ST depression were not found in patients without ischemic heart disease. Maximal ST depression was between 0.07mV and 0.53mV. The point of maximal ST depression corresponded to one of the conventional chest lead in 6 of 15 cases. In other 9 cases, the point of maximal ST depression did not correspond to the conventional chest lead and was mostly located superiorly to V3-V5. ST depression correlated well with the maximal ST depression (r=0.90). ST depression at V5 correlated less well with ST depression (r=0.70). On 201 Tl stress scan, a reversible large perfusion defect was detected in 2 out of 5 patients with marked ST depression. These findings suggested that ISP induced ST map changes are useful in diagnosis of myocardial ischemia.