The first findings from a study on spontaneous coronary artery dissection, a major cause of heart attacks in women, are reported today in a late scientific session at ESC Congress 2018.
Professor Jacqueline Saw, principal investigator at the University of British Columbia, Vancouver, Canada, said: "Spontaneous coronary artery dissection (SCAD) causes about one third of heart attacks in women under 60. SCAD was previously under-diagnosed and considered rare. Progress in intracoronary imaging techniques have an improved diagnosis, but we still know very little about the cause and natural history of SCAD. "
SCAD occurs when the lining of an artery that supplies blood to the heart, tears away from the outer layer of the artery. Blood leaks into the space between the layers and forms a clot, making the vein narrower and restricting blood flow. The symptoms are similar to a heart attack and include chest pain, rapid heartbeat, pain in the arms, shoulders or jaw, and nausea, shortness of breath, sweaty and light-headed. If you have chest pain or other symptoms, call the emergency immediately.
The treatment is aimed at restoring the blood supply to the heart. Some patients receive medication only, while others undergo a procedure to open the vein, either with a stent or by surgically bypassing the vein.
The Canadian SCAD study examined the clinical presentation, natural history, treatment and outcomes of SCAD. The researchers prospectively included 750 patients who presented acutely with SCAD at 20 centers in Canada and two centers in the US between 2014 and 2018. The diagnosis of SCAD was assessed by an angiographic core laboratory. At the start of the study, information was collected about demographic data, stress factors and disorders that could have caused SCAD and treatments. Patients are monitored for significant adverse cardiovascular events (MACE) for three years.
Today researchers report the baseline characteristics and results in the hospital and on a month. The average age of the patients in the study was 52 years and 89% were women.
Regarding the possible causes of SCAD, about half of the patients (49%) reported emotional stress prior to the event and 30% reported physical stress (in 10% this was more than 23 kg). The most common predisposing disorder was fibromuscular dysplasia (40% of the studied), which causes abnormal cell development in the blood vessels and can lead to narrowing (stenosis), aneurysms & tears (dissections). Other predisposing disorders were five or more pregnancies (10%), such as peripartum (5.3%), fertility treatment (5.1%), systemic inflammatory disorders (4.7%) and connective tissue disorders (3.5%).
Professor Saw said: "Emotional stress seems to be an important trigger for SCAD Fibromusclar dysplasia, which is more common in women than in men, also played an important role – it often has no symptoms but in some patients it causes headaches or swooshing noise in the ears called pulsatile tinnitus. "
All patients had acute coronary syndrome with their acute SCAD event, with 99.3% having a heart attack and 0.7% having unstable angina. The main symptom was chest pain, which occurred in nine out of ten patients. In angiography, the left front descending artery was most frequently affected (52%) and long diffuse narrowing was the most common feature (called type 2 SCAD, 58%).
The majority of patients were treated with medication alone (85%), 14% underwent percutaneous coronary intervention and less than 1% had coronary bypass surgery.
Almost all patients (99.9%) survived up to 30 days. The rate of MACE up to 30 days was 7.5% (including recurrent heart attack at 5.1%, cardiac arrest at 3.3%, unscheduled revascularization at 2.1%, severe heart failure at 1.5%, mechanical haemodynamic support at 1 , 5%, stroke at 1.2%, heart transplantation at 0.1% and death at 0.1% of patients). Within 30 days of discharge, 5.1% had a repeat visit to the first aid, and 2.5% were admitted for chest pain.
Professor Saw said: "Our research shows that SCAD mainly affects middle-aged women and that most acute presentations occur simultaneously with a heart attack.The vast majority of patients survived for up to 30 days with medication alone., Recurrent heart attacks and emergency room visits were high within 30 days More research is needed to determine the most appropriate treatment for patients with SCAD. "
Women who suffer from SCAD can do better with conservative care
"Canadian SCAD study – Canadian spontaneous coronary arterial dissection cohort study" will be presented during the Late Breaking Science in interventional cardiology 1 on Saturday, August 25 from 11.00 to 12.30 in the Center Stage – The Hub.