老年急性心肌梗死患者发病时间与梗死部位及ST段偏移的相关性

目的 探讨老年急性心肌梗死患者发病时间与梗死部位及ST段偏移的相关性. 方法 对909例老年急性心肌梗死患者(其中包括412例前壁和423例下壁的急性心肌梗死患者)发病时间、部位和ST段抬高及冠状动脉造影等临床资料进行分析. 结果 老年急性心肌梗死患者在清晨6时至中午12时发病为525例(57.8%).24时至清晨6时发生下壁心肌梗死138例(32.6%),与其他时间比较,差异有统计学意义(P<0.01),从清晨6时至中午12时,发生前壁心肌梗死156例(37.9%),与其他时间段比较,差异有统计学意义(P<0.01),516例冠状动脉造影的AMI患者中,24时至清晨6时发病的急性下壁心肌梗死118例,其病变累及右冠状动脉多于累及左冠状动脉分别为85.6%(101/118)和14.0%(17/118),P<0/013,清晨6时至24时发病的急性下壁心肌梗死275例,其病变累及右冠状动脉与左冠状动脉分别为54/2%(149/275)和45.8%(126/275)(P>0.05);732例急性ST段抬高患者在清晨6时至中午12时发病率最高为44.0%(263/644),265例非ST段抬高的心肌梗死24时至清晨6时发病率最高为36.6%(96/265). 结论 老年急性心肌梗死患者中,夜间非ST段抬高的发生率高于ST段抬高.由于夜间右冠状动脉闭塞所引起的急性下壁心肌梗死多于左冠状动脉,所以睡眠对老年患者的左冠状动脉累及和急性非ST段抬高性心肌梗死的保护作用是有限的.

Relationship of circadian distribution of acute myocardial infarction with AMI location and ST segment changes in elderly patients

Objective To explore the relationship of circadian distribution of acute myocardial infarction with AMI location and ST segment changes in elderly patients. Methods The time of infarction, its anatomic location, changes of ST segment, and coronary angiography were studied in 909 elderly patients with acute myocardial infarction (AMI) ( 412 with anterior AMI and 423 with inferior AMI) admitted to our coronary care units from January 1996 to January 2006. Results The onset of inferior myocardial infarction were more frequent between midnight and 6AM than other periods of the day (n=138/423,32.6% of all inferior myocardial infarction patients, P<0.01). The onset of anterior myocardial infarction were more frequent between 6AM and noon than other periods of the day (n=156/412, 37.9% of all anterior myocardial infarction patients, P<0.01). Coronary angiography was performed in 789 patients (86.8%, 516/909). 118 cases of them with inferior infarction occured between midnight and 6AM, including 85.6% of them were due to right coronary artery occlusion and 14.0%(17/118) of them were due to left coronary artery occlusion (P<0.01).275 cases of them with inferior infarction oecured between 6AM and midnight, including 52.2% (149/275) of them were due to right coronary artery occlusion and 45.8% of them were due to left coronary artery occlusion (P>0. 05). The onset of inferior myocardial infarction between 6AM and noon was the most frenquent in patients with ST segment elevation (44.0%, 263/644), while the onset of inferior myocardial infarction between midnight and 6 AM was the most frenquent in patients with non-ST segment elevation (36.6%,96/265). Conclusions The frequency of AMI at night is higher in elderly patients with ST segment elevation than in elderly patients with non-ST segment elevation.AMI at night is usually due to right coronary artery occlusion, which suggests that a protective role of sleep may be limited to left coronary artery -related events and AMI of non-ST segment.