著者

鈴木 信 秋坂 真史 野崎 宏幸

出版者

社団法人 日本循環器管理研究協議会

雑誌

日本循環器管理研究協議会雑誌 (ISSN:09147284)

巻号頁・発行日

vol.29, no.3, pp.184-189, 1995-02-01 (Released:2009-10-15)

参考文献数

27

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Two groups of peak incidence of sudden cardiac death (SCD) are apparent in the general population : one type due to myocarditis and cardiomyopathy found mainly in patients in their teens and twenties and the other stemming from ischemic heart diseases seen in patients in their fifites and sixties.Ninety percent of SCD results from tachyarrhythmias such as ventricular tachycardia and fibrillaton, the mechanism being ventricular ectopic beats induced by ischemia, autonomic nervous disorders, physical exercise, mental stress, mineral imbalances and unexpected drug effects, based upon substrate abnormalities of myocardium.In experimental models using rabbits, ventricular tachycardia and fibrillation (VT, VF) are observed immediately after marked bradyarrhythmias, such as sinus arrest and AV-block induced by brain injury and marked physical and / or mental aggression.Ventricular tachyarrhythmias, ventricular tachycardia, and fibrillation could not be seen in rabbits decorticated at the site of the hypothalamic region, suggesting that the hypothalamus has an important role in producing ventricular tachycardia and fibrillation, and is influenced by brain injury and marked aggression. Severe stresses are most likely to be associated with sudden cardiac death.Behavior patterns in humans may also be associated with SCD. Odds ratios for competitive behavior typical of type A behavior pattern (TABP) are 6.4 in ischemic heart disease (IHD) and 1.6 SCD, the former being much higher than the latter. The frequency of TABP is high among Okinawan centenarians who have not experienced IHD, and for this reason, there are some doubts whether TABP is truly a risk factor for IHD and SCD. There are two types of TABP : “self-assertive type” which include competitiveness and impatience ; and “persistent personality” characterized by “workaholic” tendencies. The role of TABP as a risk factor for SCD and IHD can be better clarified by analyzing the different components of TABP. We have tried to develop a primary screening system for SCD by combination of ECG, radiography, physical examinations, and personal history and have successfully identified in most cases at risk for SCD based on these criteria. There were a few cases that were negative but subsequently experienced SCD causes of which could not be determined by autopsy. The sensitivity of this system may be increased by detection of local gradients by VCG and / or late potential (LP) using signal averaged ECG (SAE).