Waters D, Juneau M, Baird M, Klinke P, Warnica W, Chin C, Théroux P
Department of Medicine, Montreal Heart Institute, Quebec, Canada.
J Cardiovasc Pharmacol. 1991;18 Suppl 9:S15-20.
Silent myocardial ischemia is a frequent finding when Holter monitoring is done in patients with advanced coronary disease. Silent ischemia is associated with a worse prognosis in patients with stable or unstable angina, survivors of myocardial infarction, and populations at risk for coronary disease. Whether medical therapy for silent ischemia improves prognosis is not known. In a randomized, placebo-controlled, multicenter trial of 60 patients with documented coronary disease, positive exercise tests, and ischemic episodes on Holter monitoring, long-acting diltiazem reduced ischemic episodes by 50% compared to placebo, from a mean of 5.6 to 2.8 (p less than 0.0001). Efficacy was maintained over 24 h and diltiazem also significantly improved exercise test parameters. Three smaller studies also demonstrated that diltiazem effectively reduces ambulatory ischemia; however, results with nifedipine are conflicting, with several studies showing no benefit. In contrast, beta-blockers reliably reduce ischemic episodes. The role of medical therapy for silent ischemia will be clarified only when its effect upon morbidity and mortality are determined.
在对患有晚期冠状动脉疾病的患者进行动态心电图监测时，无症状性心肌缺血是一种常见的发现。无症状性缺血与稳定型或不稳定型心绞痛患者、心肌梗死幸存者以及冠心病高危人群的预后较差有关。无症状性缺血的药物治疗是否能改善预后尚不清楚。在一项针对60例有冠心病记录、运动试验阳性且动态心电图监测有缺血发作的患者的随机、安慰剂对照、多中心试验中，与安慰剂相比，长效地尔硫䓬使缺血发作减少了50%，从平均5.6次降至2.8次（p小于0.0001）。疗效在24小时内得以维持，地尔硫䓬还显著改善了运动试验参数。三项规模较小的研究也表明地尔硫䓬能有效减少动态缺血；然而，硝苯地平的结果存在矛盾，几项研究显示无益处。相比之下，β受体阻滞剂能可靠地减少缺血发作。只有当确定无症状性缺血的药物治疗对发病率和死亡率的影响时，其作用才能得以明确。
