Cas L D, Metra M, Nodari S, Nardi M, Giubbini R, Visioli O
Cattedra di Cardiologia, Università degli Studi, Brescia.
Cardiologia. 1993 Dec;38(12 Suppl 1):415-25.
The role of mental stress in ischemic heart disease is two-fold: as a risk factor of coronary artery disease and as a trigger of acute ischemic attacks in patients with established coronary atherosclerosis. The role of stress as a risk factor is still controversial. Data regarding the relationship between occupational factors and development of coronary atherosclerosis have not been confirmed. A type personality, above all when anger and hostility traits are present, seems to be a predisposing factor for the development of coronary artery disease. These data however, were not confirmed in study groups including patients with a higher prevalence of other, more important, risk factors. Stress can have an important role as a trigger of acute ischemic attacks. This is indirectly shown by the circadian distribution of the main manifestations of ischemic heart disease (sudden death, myocardial infarct, ST segment depression). In fact, their incidence is significantly higher in the morning hours, after awakening, when mental stress is higher. In the laboratory setting, mental stress can induce myocardial ischemia in a variable percentage of patients (0 to 80%). Prevalence of mental stress-induced myocardial ischemia varies depending on the stressor used, the patients group and, above all, the diagnostic tool. Ischemic episodes induced by mental stress, in fact, are generally silent and less severe and extensive than those elicited by exercise stress testing. It is therefore often necessary to use methods, such as myocardial scintigraphy, with higher sensitivity for the detection of myocardial ischemia in comparison with ECG. Patients with mental stress-induced myocardial ischemia tend to present higher scores on measures of aggressivity, anger and hostility. These psychological features are related to a hightened cardiovascular reactivity with a brisk and greater increase in heart rate and blood pressure after exposure to stress. It would be therefore useful to identify patients with such a behaviour by psychological assessment and/or analysis of sympatho-vagal balance by analysis of heart rate variability. The mechanism by which mental stress can induce myocardial ischemia is represented by an increase in myocardial oxygen demand, through the increased heart rate and blood pressure, probably associated with an increase in coronary vascular resistance. This last phenomenon is likely caused by small coronary vessel constriction mediated by alpha-adrenergic activation and by a reduced EDRF release by the damaged endothelium.
一是作为冠状动脉疾病的危险因素，二是作为已患冠状动脉粥样硬化患者急性缺血发作的诱因。压力作为危险因素的作用仍存在争议。关于职业因素与冠状动脉粥样硬化发展之间关系的数据尚未得到证实。A型人格，尤其是当存在愤怒和敌意特质时，似乎是冠状动脉疾病发展的一个易感因素。然而，在包括其他更重要危险因素患病率较高的患者的研究组中，这些数据并未得到证实。压力作为急性缺血发作的诱因可能起重要作用。缺血性心脏病主要表现（猝死、心肌梗死、ST段压低）的昼夜分布间接表明了这一点。事实上，在早晨醒来后，当心理压力较高时，它们的发生率显著更高。在实验室环境中，心理压力可在不同比例的患者（0%至80%）中诱发心肌缺血。心理压力诱发的心肌缺血的患病率因所使用的应激源、患者群体，尤其是诊断工具而异。事实上，心理压力诱发的缺血发作通常是无症状的，且比运动应激试验诱发的缺血发作程度更轻、范围更小。因此，与心电图相比，通常需要使用心肌闪烁显像等对检测心肌缺血具有更高敏感性的方法。心理压力诱发心肌缺血的患者在攻击性、愤怒和敌意测量方面往往得分较高。这些心理特征与心血管反应性增强有关，在暴露于压力后心率和血压会迅速且大幅升高。因此，通过心理评估和/或通过分析心率变异性来分析交感 - 迷走神经平衡，识别具有这种行为的患者可能会有所帮助。心理压力诱发心肌缺血的机制表现为通过心率和血压升高导致心肌需氧量增加，这可能与冠状动脉血管阻力增加有关。最后这种现象可能是由α - 肾上腺素能激活介导的小冠状动脉血管收缩以及受损内皮细胞释放内皮舒张因子减少所致。
