Etiology of Acute Coronary Syndrome after Noncardiac Surgery

Abstract

Background The objective of this investigation was to determine the etiology of perioperative acute coronary syndrome with a particular emphasis on thrombosis versus demand ischemia. Methods In this retrospective cohort study, adult patients were identified who underwent coronary angiography for acute coronary syndrome within 30 days of noncardiac surgery at a major tertiary hospital between January 2008 and July 2015. Angiograms were independently reviewed by two interventional cardiologists who were blinded to clinical data and outcomes. Acute coronary syndrome was classified as ST–elevation myocardial infarction, non–ST–elevation myocardial infarction, or unstable angina; myocardial infarctions were adjudicated as type 1 (plaque rupture), type 2 (demand ischemia), or type 4b (stent thrombosis). Results Among 215,077 patients screened, 146 patients were identified who developed acute coronary syndrome: 117 were classified as non–ST–elevation myocardial infarction (80.1%); 21 (14.4%) were classified as ST–elevation myocardial infarction, and 8 (5.5%) were classified as unstable angina. After coronary angiography, most events were adjudicated as demand ischemia (type 2 myocardial infarction, n = 106, 72.6%) compared to acute coronary thrombosis (type 1 myocardial infarction, n = 37, 25.3%) and stent thrombosis (type 4B, n = 3, 2.1%). Absent or only mild, nonobstructive coronary artery disease was found in 39 patients (26.7%). In 14 patients (9.6%), acute coronary syndrome was likely due to stress-induced cardiomyopathy. Aggregate 30-day and 1-yr mortality rates were 7 and 14%, respectively. Conclusions The dominant mechanism of perioperative acute coronary syndrome in our cohort was demand ischemia. A subset of patients had no evidence of obstructive coronary artery disease, but findings were consistent with stress-induced cardiomyopathy.

Frontline Science: Low regulatory T cells predict perioperative major adverse cardiovascular and cerebrovascular events after noncardiac surgery

“…Atherosclerotic lesions are the underlying substrate for cardiovascular events such as the individual components of the primary endpoint MACCE. Rupture of destabilized atherosclerotic plaques is seen in approximately 25% of all perioperative MIs . Nonspecific inflammation induced by conditions such as surgical trauma, pain, or blood loss constitutes a second hit, which might put surgical patients at risk for atherosclerotic lesion destabilization.…”

Clinical and Pathological Analysis of Sudden Death after Planned Surgery

“…провели анализ 223 случаев остановки сердца, которая происходила между вводным наркозом и палатой пробуждения у пациентов, и уста- [15]. Эти данные свидетельствуют о том, что значительная доля смертельных периоперационных инфарктов миокарда может быть результатом увеличения потребности в кислороде миокарда в условиях фиксированных стенозов коронарных артерий [16]. При этом имеются результаты другого исследования с участием пациентов кардиохирургического профиля, где показано, что большинство нелетальных периоперационных инфарктов миокарда происходило в артериях без выраженных стенозов, а значит, события могли быть вызваны повреждением атеросклеротических бляшек и острым тромбозом коронарной артерии [17].…”

Platelet Transfusion in Perioperative Medicine

“…In patients not treated for coronary heart disease before surgery by antiplatelet drugs, more than 70% of myocardial infarctions are caused by supply/demand mismatches. 100 It is likely that patients on antiplatelet therapy also have an increased risk for this complication, especially if bleeding causes circulatory distress. 101 Therefore, it is highly relevant to prevent both bleeding and thrombotic coronary occlusion in patients with cardiac disease because both contribute to the perioperative risk of MACCE.…”