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Page 2 of 13 Zahrai et al. Vessel Plus 2023;7:32 https://dx.doi.org/10.20517/2574-1209.2023.100

catheter-based, and surgical management . When treating AMI, clinicians need to decide on methods that
[3]
lead to the least amount of harm to each unique patient.

AMI patients who have hemodynamic instability and/or ongoing ischemia, particularly in the presence of
[4]
an ST-elevation myocardial infarction (STEMI), may be candidates for emergency revascularization . A
small proportion of STEMI patients may require emergency surgery due to mechanical complications of
[5,6]
STEMI . However, this review will focus on the larger group requiring intervention solely for
revascularization. In particular, the strategies that have been proposed include complete revascularization to
address all identified coronary stenoses, or a limited revascularization of the culprit vessel responsible for
the acute event, with consideration given to revascularize any remaining areas of potential ischemic
jeopardy at a later time. As discussed below, this review will focus on the data supporting the timing of
surgery in the context of an AMI, particularly after percutaneous coronary intervention (PCI). When done
too early, coronary artery bypass grafting (CABG) has been associated with injury from reperfusion and
[7,8]
systemic inflammation, poor postoperative outcomes, and an increase in mortality . On the other hand,
delayed surgery may put the patient at risk for recurrent ischemia with the potential for myocardial loss and
worsening left ventricular function [9,10] .

Recent studies have provided insight into the role that patient parameters, such as AMI type, left
ventricular, pulmonary function, and others, could inform the process of surgical revascularization
timing [10,11] . There also appears to be a scarcity of robust clinical trials studying AMI patients who do not
respond successfully to initial PCI or who are eligible for first-line surgical revascularization. In this review,
we summarize the current evidence to guide decision-making for the timing of surgical revascularization for
AMI patients.

HISTORY OF CORONARY REVASCULARIZATION IN AMI
Management of AMI has dramatically evolved owing to insights into the pathophysiology of coronary
artery disease (CAD). In the mid-twentieth century, prolonged bedrest with oxygen and intravenous fluid
therapy served as the principal treatment modality for AMI, often with fatal results . Medical therapeutic
[12]
interventions have included the introduction of coronary care units with improved monitoring and
management of arrhythmias , and the generalized use of aspirin as a potent platelet aggregation
[13]
inhibitor [14-16] .

The recognition that AMI was a result of acute coronary thrombosis stimulated the introduction of
thrombolysis with streptokinase as the first targeted revascularization approach in 1978, with moderate
clinical success [12,17] . In parallel to this innovation, CABG was growing as a first-line revascularization
therapy for CAD [18,19] . Investigations comparing surgical and non-surgical management of AMI patients
included only nonrandomized data due to challenges with performing a clinical trial on surgical
reperfusion [20,21] . This changed when Koshal et al. conducted the first randomized trial in 1988 to compare
[22]
surgical revascularization with conventional medical methods (excluding thrombolysis) for treating AMI .
The authors discovered that urgent surgical reperfusion in AMI reduces early and late mortality compared
to medical therapy.

PCI emerged in the 1970s when Andreas Gruentzig performed the first successful PCI in a 38-year-old with
[23]
[24]
stable angina in 1977 . Two years later, Geoffrey Hartzler introduced primary angioplasty to treat AMI .
Several randomized trials and large registry studies subsequently compared primary angioplasty and
thrombolysis, and a large meta-analysis of randomized trials including 7,739 patients confirmed the
reduction in mortality, nonfatal reinfarction, and stroke with primary PCI, thereby justifying its wide use
today .
[25]