Early Discharge After ST-Segment Elevation Myocardial Infarction

The Days Are Getting Shorter!

Cindy L. Grines, MD; J. Jeffrey Marshall, MD


J Am Coll Cardiol. 2022;78(25):2561-2562. 

Early hospital discharge after ST-segment elevation myocardial infarction (STEMI) is now well accepted. With the first randomized trial of early discharge in patients treated with primary percutaneous coronary intervention (PCI), we demonstrated in the PAMI–2 (Primary Angioplasty in Myocardial Infarction–2) study the ability to use acute angiographic and clinical data to identify low-risk patients.[1] These 471 patients were randomized to the standard hospital stay vs an accelerated approach that omitted the intensive care unit, avoided all noninvasive testing, and discharged the patient on day 3. We found this accelerated approach to be safe and cost-effective. Using data sets from our trials of thousands of patients, the PAMI risk score was created to identify predictors of mortality after primary PCI.[2] Subsequently, 4 additional randomized trials of early discharge were conducted, and a meta-analysis of 1,575 randomized patients confirmed that early discharge of low-risk individuals at 2 to 3 days was safe.[3] Currently, the guidelines of the European Society of Cardiology[4] state that selected patients may be considered for early discharge 72 hours after STEMI (Class IIb). Although the U.S. guidelines do not comment on length of stay, early discharge after primary PCI is widely embraced, even among selected older patients.[5] With the advent of radial access for PCI and performance of outpatient elective PCI, it was only a matter of time before length of stay was further shortened after primary PCI.

In this issue of the Journal, Rathod et al[6] report their observational series of patients with STEMI who were treated with primary PCI at a single high-volume center and who were stratified into high- and low-risk groups. Patients enrolled between April 2020 and June 2021 who were thought to be at low risk of major adverse cardiac events followed an early discharge pathway to be sent home by 48 hours, with very close telemedicine follow-up and with free blood pressure machines provided to the patients. The comparator group was a >48-hour low-risk group (n = 700) of patients who, despite meeting the early discharge criteria, were hospitalized for >48 hours according to physician discretion. Rathod et al[6] used well-established criteria for determination of low-risk status (ejection fraction >40%, successful PCI with flow grade 3, absence of multivessel disease requiring inpatient revascularization, Killip class 1, no recurrent ischemia or arrhythmias, and appropriate social situation for early discharge).

This study is unique given the short median length of stay (24.6 hours) and the long duration of follow-up (median 271 days), during which time there were no cardiovascular deaths, and major adverse cardiac events occurred in only 1.2%. Rathod et al[6] should be congratulated on their outstanding results and ability to move the target discharge time even shorter than previously attempted. Early discharge at 24 hours was likely facilitated by the presence of the coronavirus disease 2019 pandemic, with concerns about patient risk of exposure in the hospital and the lack of beds. Importantly, these excellent clinical outcomes were achieved by a highly sophisticated and coordinated team approach with high-volume operators using PCI protocols to reduce the risk of bleeding (radial access in 94%) and thrombosis (dual antiplatelet therapy loading before the procedure, heparin dose 100 U/kg). It should also be pointed out that early discharge was applied to patients treated very early (median symptom onset to reperfusion of only 80 minutes, door-to-balloon time of 50 minutes), thus suggesting there may have been minimal myocardial damage from the STEMI. Moreover, there was some operator selection bias (perhaps appropriately so) because low-risk patients who stayed longer than 48 hours were more likely to have anterior myocardial infarction, multivessel disease, and multivessel PCI. In fact, we suggest other areas of concern where physician judgment may overrule the early discharge protocol, such as very late reperfusion (the maximum duration of myocardial infarction to reperfusion was only 4 hours in the current study), advanced age, severe renal insufficiency, profound anemia, cardiac arrest requiring more than brief resuscitation, bleeding complications, or symptomatic coronavirus disease 2019. It is somewhat concerning that Rathod et al[6] required only 12 hours of cardiac rhythm monitoring, but perhaps that is acceptable in patients whose myocardial damage is minimal (35% of patients had no left ventricular dysfunction). Finally, in the absence of such dedicated and frequent telemedicine follow-up, early discharge may increase the risk of readmission.[7]

In summary, Rathod et al[6] have demonstrated the ability to safely discharge very low-risk patients 24 hours after primary PCI for STEMI. Although we believe the discharge criteria should include other factors associated with poor outcomes, their study should cause cardiologists to rethink the ultralow-risk STEMI pathway. However, it is unlikely that the American College of Cardiology and American Heart Association or European Society of Cardiology guidelines will shorten the length of stay to ≤24 hours on the basis of an observational report from a single center. Future randomized trials of very early discharge vs standard discharge will be necessary.