Smilowitz Nathaniel R, Subramanyam Pritha, Gianos Eugenia, Reynolds Harmony R, Shah Binita, Sedlis Steven P
Department of Medicine, Division of Cardiology, NYU School of Medicine.
Department of Medicine, Icahn School of Medicine at Mount Sinai.
Coron Artery Dis. 2018 Jan;29(1):46-52. doi: 10.1097/MCA.0000000000000545.
Type 2 myocardial infarction (MI) is defined by a rise and fall of cardiac biomarkers and evidence of ischemia without unstable coronary artery disease (CAD) because of a mismatch in myocardial oxygen supply and demand. Myocardial injury is similar but does not fulfill the clinical criteria for MI. There is uncertainty in terms of the clinical characteristics, management, and outcomes of type 2 MI and myocardial injury in comparison with type 1 MI.
Patients admitted to a Veterans Affairs tertiary care hospital with a rise and fall in cardiac troponin were identified. MI and injury subtypes, presentation, management, and outcomes were determined.
Type 1 MI, type 2 MI, and myocardial injury occurred in 137, 146, and 175 patients, respectively. Patients with type 2 MI were older (P=0.02), had lower peak cardiac troponin (P<0.001), and were less likely to receive aspirin and statin at discharge (P<0.001) than type 1 MI survivors. All-cause mortality (median follow-up: 1.8 years) was not different between patient groups (type 1 MI mortality: 29.9%, type 2 MI: 30.8%, myocardial injury: 29.7%; log rank P=0.94). A significant proportion of deaths were attributed to cardiovascular causes in all subgroups (type 1 MI: 34.1%, type 2 MI: 17.8%, myocardial injury: 30.8%).
Patients with type 2 MI and myocardial injury were less likely to receive medical therapy for CAD than those with type 1 MI. No differences in all-cause mortality among MI subtypes were observed. Additional studies to determine optimal medical therapy and risk stratification strategies for these high-risk populations are warranted.
2型心肌梗死（MI）的定义为心肌生物标志物升高和降低，且存在心肌缺血证据，但无不稳定冠状动脉疾病（CAD），原因是心肌氧供需不匹配。心肌损伤与之相似，但不符合MI的临床标准。与1型MI相比，2型MI和心肌损伤的临床特征、管理及预后存在不确定性。
确定入住退伍军人事务部三级护理医院且心肌肌钙蛋白升高和降低的患者。确定MI和损伤亚型、表现、管理及预后。
分别有137例、146例和175例患者发生1型MI、2型MI和心肌损伤。与1型MI幸存者相比，2型MI患者年龄更大（P = 0.02），心肌肌钙蛋白峰值更低（P < 0.001），出院时接受阿司匹林和他汀类药物治疗的可能性更小（P < 0.001）。各患者组间全因死亡率（中位随访时间：1.8年）无差异（1型MI死亡率：29.9%，2型MI：30.8%，心肌损伤：29.7%；对数秩检验P = 0.94）。所有亚组中相当一部分死亡归因于心血管原因（1型MI：34.1%，2型MI：17.8%，心肌损伤：30.8%）。
与1型MI患者相比，2型MI和心肌损伤患者接受CAD药物治疗的可能性更小。未观察到MI各亚型间全因死亡率存在差异。有必要开展进一步研究以确定这些高危人群的最佳药物治疗和风险分层策略。
