Department of Medicine, University of Florida College of Medicine, Gainesville, Florida 32610, USA.
J Am Coll Cardiol. 2012 Jan 31;59(5):435-41. doi: 10.1016/j.jacc.2011.07.050.
Myocardial ischemia can occur without overt symptoms. In fact, asymptomatic (or silent) ST-segment depression during ambulatory electrocardiogram monitoring occurs more often than symptomatic ST-segment depression in patients with coronary artery disease. Initial studies documented that silent ischemia provided independent prediction of adverse outcomes in patients with known and unknown coronary artery disease. The ACIP (Asymptomatic Cardiac Ischemia Pilot Study) enrolled patients in the 1990s and found that revascularization was better than medical therapy in reducing silent ischemic episodes and possibly cardiovascular (CV) events. However, the more recent COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial found similar CV event rates between patients treated with optimal medical therapy alone and those treated with optimal medical therapy plus percutaneous revascularization. Therefore, in the current era, medical therapy appears to be as effective as revascularization in suppressing symptomatic ischemia and preventing CV events. COURAGE was not designed to evaluate changes in the frequency of silent ischemia. Therefore, silent ischemia may persist despite current-era treatment and might still identify patients with increased risk of CV events. Also, silent ischemia is likely to occur frequently in heart transplant patients with denervated hearts and coronary allograft vasculopathy, and future study aimed at improving the management of silent ischemia in this population is warranted. Additionally, future research is warranted to study the effect of newer medical therapies such as ranolazine or selected use of revascularization (for example, guided by fractional flow reserve) in those patients with persistent silent ischemia despite optimal current-era medical therapy.
心肌缺血可无明显症状。事实上，在动态心电图监测中，无症状（或无声）的 ST 段压低比有症状的 ST 段压低更为常见，尤其是在有冠状动脉疾病的患者中。最初的研究表明，无声性心肌缺血为有或无已知冠状动脉疾病的患者提供了独立的预后不良预测。ACIP（无症状性心肌缺血先导研究）在 20 世纪 90 年代招募了患者，结果显示血管重建术在减少无声性缺血发作和可能的心血管（CV）事件方面优于药物治疗。然而，最近的 COURAGE（经皮血管重建术与强化药物治疗评估以改善临床转归）试验发现，仅接受最佳药物治疗的患者和接受最佳药物治疗加经皮血管重建术的患者之间的 CV 事件发生率相似。因此，在当前时代，药物治疗在抑制有症状性缺血和预防 CV 事件方面似乎与血管重建术一样有效。COURAGE 试验并非旨在评估无声性缺血的发生率变化。因此，尽管采用了当前时代的治疗方法，无声性缺血仍可能持续存在，并且仍可能识别出 CV 事件风险增加的患者。此外，在去神经心脏和冠状动脉移植血管病变的心脏移植患者中，无声性缺血可能经常发生，因此需要进一步研究以改善该人群中无声性缺血的管理。此外，还需要进一步研究新的药物治疗（例如雷诺嗪）或在最佳当前时代药物治疗后仍存在持续无声性缺血的患者中选择使用血管重建术（例如，通过血流储备分数指导）的效果。
