Candinas R A, Podrid P J
Section of Cardiology, Boston University School of Medicine, University Hospital.
Herz. 1990 Feb;15(1):1-10.
Ambulatory ECG monitoring has enabled documentation of the type and frequency of ventricular arrhythmias and their relation to symptoms as well as prognosis. On 24-hour ambulatory ECG monitoring, ventricular premature beats (VPB) can be found in healthy subjects with a prevalence of 40 to 80% which is directly related to age. Complex ventricular arrhythmias are uncommon. The prevalence of VPB is higher in patients who have underlying structural heart disease; in those resuscitated from out of hospital sudden cardiac death, it is reported to be 100%. One of the most important concerns with regard to ventricular arrhythmias is the problem of spontaneous variability. There is, however, a higher degree of reproducibility on two consecutive days in patients with more than 300 VPB/hour and in patients who have experienced sustained ventricular tachycardia than in those with infrequent VPB. When ambulatory monitoring is repeated months up to one year after the initial investigation, reproducibility of arrhythmias is poor. The mechanism of sudden cardiac death has been shown to be ventricular tachycardia or ventricular fibrillation, both of which are associated with an antecedent increase in VPB. In patients with chronic coronary artery disease, idiopathic or hypertrophic cardiomyopathy, a relationship between the presence of ventricular arrhythmias and sudden cardiac death has been described but VPB are considered to be of independent prognostic value only in those with myocardial infarction. Ambulatory ECG monitoring is the preferred noninvasive method for drug evaluation in patients with frequent ventricular arrhythmias. In general, the available antiarrhythmic drugs are effective for suppression of ventricular arrhythmias in 45 to 80% of patients. As a side-effect dependent on the underlying condition, the incidence of proarrhythmic effects varies from 6 to 19%. Medical treatment may be effective in prolonging life in resuscitated patients. Limitations of ambulatory monitoring include low reliability in the presence of infrequent ventricular arrhythmias or marked spontaneous variability, low specificity with respect to prognosis, lack of standardized definition for treatment efficacy and problems of recognizing complex forms of ventricular arrhythmias.
动态心电图监测能够记录室性心律失常的类型和频率、其与症状的关系以及预后情况。在24小时动态心电图监测中，健康受试者中可发现室性早搏（VPB），其发生率为40%至80%，且与年龄直接相关。复杂室性心律失常并不常见。有潜在结构性心脏病的患者中VPB的发生率更高；据报道，从院外心脏性猝死中复苏的患者中VPB的发生率为100%。关于室性心律失常，最重要的问题之一是自发变异性问题。然而，每小时VPB超过300次的患者以及经历过持续性室性心动过速的患者，其连续两天的重复性程度高于VPB不频繁的患者。当初次检查数月至一年后重复进行动态监测时，心律失常的重复性较差。心脏性猝死的机制已被证明是室性心动过速或心室颤动，这两者都与VPB先前增加有关。在慢性冠状动脉疾病、特发性或肥厚型心肌病患者中，已描述了室性心律失常的存在与心脏性猝死之间的关系，但仅在心肌梗死患者中，VPB被认为具有独立的预后价值。动态心电图监测是频繁室性心律失常患者药物评估的首选非侵入性方法。一般来说，现有的抗心律失常药物对45%至80%的患者抑制室性心律失常有效。作为取决于基础疾病的副作用，促心律失常作用的发生率为6%至19%。药物治疗可能对复苏患者延长生命有效。动态监测的局限性包括存在不频繁室性心律失常或明显自发变异性时可靠性低、对预后的特异性低、治疗疗效缺乏标准化定义以及识别复杂形式室性心律失常存在问题。
