Data from the Canadian Spontaneous Coronary Artery Disease (CanSCAD) study indicate that the majority of patients with non-atherosclerotic spontaneous coronary artery dissection are young to middle-aged women who present with myocardial infarction. Furthermore, they indicate that, despite conservative therapy, 30-day survival is good but cardiovascular outcomes (such as recurrent myocardial infarction) can occur.
Presenting the findings at the 2018 European Society of Cardiology (ESC) Congress (25–29 August, Munich, Germany), Jacqueline Saw (Vancouver General Hospital, Vancouver, Canada) said that the first case of spontaneous coronary artery dissection was reported in 1931 but the condition remained “poorly understood” and underdiagnosed”. She added that although “early myths”, such as it being a rare condition, had been debunked, “there remains uncertainties regarding management, predisposing/precipitating causes and outcomes”.
Therefore, the aim of the multicentre observational study was to describe the natural history of non-atherosclerotic spontaneous coronary artery disease, assess the in-hospital and long-term cardiovascular outcomes with the condition, and identify factors associated with these outcomes. Saw and colleagues prospectively enrolled patients if they had new acute non-atherosclerotic spontaneous coronary artery dissection that was documented on angiogram (confirmed by core laboratory). The investigators reviewed the patients’ baseline characteristics, coronary angiograms, in-hospital outcomes, and post discharge outcomes at one, six, 12, 24, and 36 months.
Of the 750 patients included in the analysis, the majority were women (88.5%) and most of these patients were postmenopausal. Overall, the mean age was 51.8±10.2 (age range 24–89 years) with nearly 10% (9.2%) of patients aged over 65 years. Saw reported that most patients presented with myocardial infarction with 69.9% presenting with non-ST-segment elevation myocardial infarction (NSTEMI) and 29.7% presenting with STEMI; only 0.4% of patients had unstable angina.
“In terms of revascularisation therapy, conservative therapy was used in 84.3% of these patients, 1.5% per cent received fibrinolysis, 14.1% underwent percutaneous coronary intervention (PCI), and 0.7% underwent coronary artery bypass grafting (CABG),” Saw told the ESC audience. She added that the main reasons for performing revascularisation included ongoing chest pain, ongoing ischaemia on ECG, or dissection causing severe stenosis.
Overall, the median rate of major adverse events (MAE) was 8.8% and the median hospital stay was four days. The 30-day rate of major adverse cardiac events (MACE) was also 8.8% with the majority of events occurring within 10 days of discharge. According to Saw, peripartum patients had a significantly higher rate of in-hospital MAE (20.6% vs. 8.2% for non-peripartum patients; p=0.023) and a significantly higher rate of in-hospital high-risk events (23.5% vs. 6.8%; p<0.003). She said: “Indeed, peripartium status was an independent predictor of both in-hospital MAE and 30-day MACE as was connective tissue disorder.”
Saw concluded: “Spontaneous coronary artery dissection predominantly affected young to middle-aged women and presented with myocardial infarction. Despite conservative therapy in the majority of patients, in-hospital and 30-day survival was good. However, significant cardiovascular events accrued within 30 days’ post event, including recurrent myocardial infarction, unplanned revascularisation, and stroke/transient ischaemic attack.” She added that as peripartium status and connective tissue disorder were both independent predictors of 30-day MACE, patients with these predictors should stay in hospital for longer than the four days that is typical for patients with spontaneous coronary artery dissection patients.
Saw told Cardiovascular News: “Spontaneous coronary artery dissection has been neglected for decades. It is important to have greater awareness for spontaneous coronary artery dissection as it is a major cause of myocardial infarction in young to middle-aged women. This disease is frequently missed and misdiagnosed. We need to educate the medical community to think of spontaneous coronary artery dissection in the differential diagnosis when a young/middle-aged women present with MI, and become familiar with how to diagnose and manage this condition.