Percutaneous coronary intervention is a feasible treatment option associated with reasonably good outcomes in patients with acute myocardial infarction and thrombosis of the unprotected left main coronary artery, a new study has shown. The results of the investigation, conducted in Italy and the UK, showed that long-term prognosis is “excellent” in hospital survivors with an 89.5% survival rate at one year.
The study “Percutaneous coronary intervention of unprotected left main coronary artery disease as culprit lesion in patients with acute myocardial infarction”, by Alessandro Pappalardo et al, was published in June in the Journal of the American College of Cardiology: Cardiovascular Interventions.
This study sought to evaluate short- and long-term outcomes of patients undergoing emergency percutaneous coronary intervention for acute myocardial infarction due to a culprit lesion in an unprotected left main coronary artery.
In this retrospective, two-centre, international observational study, 5,261 patients were admitted between February 2005 and December 2008 with acute myocardial infarction and treated with percutaneous coronary intervention; of these, 1,277 were ST-segment elevation myocardial infarction and 3,984 non–ST-segment elevation myocardial infarction.
The investigators identified 48 patients among this cohort who underwent emergency percutaneous coronary intervention to an unprotected left main coronary artery culprit lesion.
Mean age was 70±12.5 years, and 45% of the patients presented with ST-segment elevation myocardial infarction or new left bundle branch block. Cardiogenic shock was present in 45%, and distal left main coronary artery disease was present in 71% of patients.
Angiographic procedural success was achieved in 92% of patients. Overall in-hospital mortality was 21%, due in all cases to refractory, multi-organ failure. Twenty five per cent experienced major adverse cardiac events, defined as death, myocardial infarction, stent thrombosis, and target vessel revascularisation. In patients presenting in cardiogenic shock, in-hospital mortality was 32%.
At one-year follow-up, in-hospital survivors had a mortality rate of 10.5%, whereas 18.4% experienced subsequent major adverse cardiac events. “Long-term prognosis was excellent in hospital survivors with a one-year survival rate of 89.5%,” the authors wrote.
“Unprotected left main coronary artery culprit disease in patients presenting with acute coronary syndrome is rare but is associated with high in-hospital mortality, especially in those presenting with cardiogenic shock. We demonstrate in this study that PCI is a feasible treatment option in these patients and is a reasonable alternative to surgical revascularisation,” the authors said. “Despite the extensive use of haemodynamic support, a 21% in-hospital mortality rate was observed in this study, although for those who survive to hospital discharge, a much better prognosis is recorded, with a 10.5% mortality rate at one year. Without randomised trial data, the decision to perform CABG or PCI in acute myocardial infarction patients with unprotected left main coronary artery disease is difficult, and the decision needs to be individualised, taking into consideration potential risks involved for each treatment strategy. Ultimately, randomised, controlled trials will be needed to further elucidate the optimal treatment strategy, although PCI is both feasible and associated with acceptable outcomes as demonstrated in this study.”