Temporal Trends in the characteristics, treatment and prognosis of conservatively managed patients with acute myocardial infarction: ACSIS registry 2000-2016

Background: Despite advances in percutaneous coronary interventions, a sub group of acute myocardial infarction (AMI) patients are still being managed by a conservative, noninvasive approach, as dictated by their general medical condition, known or presumed comorbidities, and available resources. We sought to characterize a contemporary, large, real-world cohort of AMI patients selected for non-invasive, medical-only management.

Methods: The Acute Coronary Syndrome (ACS) Israeli Survey (ACSIS) in 2000-2016, which encompass all consecutive patients admitted to cardiology wards with an ACS diagnosis, was used for data analysis. Characteristics and management were examined in 3554 conservatively managed AMI patients. Primary endpoints were 30d major adverse cardiovascular events (MACE) and 1-year survival. Additional outcomes included recurrent MI, atrial fibrillation, acute kidney injury, bleeding, and heart failure symptoms. Patients with ST elevation MI, unstable angina pectoris, and those referred to surgical treatment were excluded. The study cohort was divided to 4 time-periods in order to examine temporal trends.

Results: Over 2 decades, AMI patients managed conservatively were more likely to have atherosclerotic risk-factors and comorbidities. Median age remained unchanged (67±13y, p=0.5). Despite this, during time, more diagnostic angiographies have been performed (p<0.001). more patients have been treated with Statins (p<0.001), Angiotensin converting enzyme inhibitors\Angiotensin Receptor Blockers (p<0.001) and Clopidogrel (p<0.001). The rate of 30d MACE has decreased during time (from 20.7% to 10.2%, earliest to latest period, respectively, p<0.001) but 1-year survival remained unchanged (14.8% vs. 11.6%, p=0.06; Figure 1). Other clinical outcomes have improved, including kidney injury (p=0.001) and heart failure (p<0.001).

Conclusion: During the last 2 decades, in AMI patients who were managed conservatively, short term prognosis has improved significantly, while 1-year mortality remained unchanged, likely due to additional comorbidities. Further studies are needed to examine treatment modalities in these unique AMI patients.

Figure 1:

Figure 1: Kaplan Meyer survival curves of conservatively managed AMI patients within the 4 time periods.