Biagini A, Carpeggiani C, Mazzei M G, Testa R, Michelassi C, Antonelli R, L'Abbate A, Maseri A
G Ital Cardiol. 1981;11(1):4-11.
Aim of the study was to evaluate whether frequency of myocardial ischemic attacks at rest (IA) had any identifiable distribution during 24-hour periods. Two ECG leads were continuously recorded by an Oxford 4-24 tape recorder for a total of 148 days in 10 patients admitted to CCU because of frequent spontaneous anginal attacks. During 48 days, in absence of therapy, 682 IA were recorded (2.03 per patient per day). They showed a symmetrical bell-shaped distribution curve in the 24 hour periods with a peak occurring at 5 a.m. and 43% of IA from 0 to 6 a.m. Only 25% of IA was symptomatic with the lowest values (10%) between 2 and 6 a.m. Distribution of IA was independent from their distinctive electrocardiographic feature [ST (71%) or T changes]. During 100 days with therapy [Verapamil and/or Isosorbide dinitrate ointment) a marked reduction of episodes was observed (0.64 per patient per day), while their distribution, the incidence of different electrocardiographic patterns and percentage of symptomatic IA remained unchanged. Attenuated incidence, but inalterated distribution of IA with therapy suggest its possible effect on the threshold response of coronary smooth muscle to vasoconstrictor stimuli rather than its primary effect on pathogenetic factors.
本研究的目的是评估静息时心肌缺血发作（IA）的频率在24小时期间是否有任何可识别的分布规律。10名因频繁自发性心绞痛发作而入住冠心病监护病房（CCU）的患者，用牛津4 - 24磁带记录仪连续记录两个心电图导联，共记录148天。在48天未进行治疗期间，记录到682次IA发作（每位患者每天2.03次）。这些发作在24小时期间呈现出对称的钟形分布曲线，峰值出现在凌晨5点，0至6点期间的IA发作占43%。只有25%的IA发作有症状，其中凌晨2点至6点期间症状发作的比例最低（10%）。IA发作的分布与其独特的心电图特征[ST段改变（71%）或T波改变]无关。在接受治疗的100天[维拉帕米和/或硝酸异山梨酯软膏]期间，观察到发作次数显著减少（每位患者每天0.64次），而其分布、不同心电图模式的发生率以及有症状IA发作的百分比均保持不变。治疗后IA发作的发生率降低但分布不变，这表明其可能对冠状动脉平滑肌对血管收缩刺激的阈值反应产生影响，而非对发病因素的主要作用。
