Spontaneous coronary artery dissection (SCAD) in stable patients is best treated conservatively with in-hospital monitoring rather than invasive treatment, despite the typical appearance of atherosclerotic heart attack, according to a new statement from the American Heart Association.
The condition occurs overwhelmingly in women, accounting for up to 35% of myocardial infarctions (MIs) in those under age 50, Sharonne Hayes, MD, of the Mayo Clinic in Rochester, MN, and colleagues wrote in the statement, published in . The presentation is almost always as an acute coronary syndrome (ACS) with elevated cardiac enzymes, which appears consistent with atherosclerotic disease but does not stem from it, she and her colleagues noted.
Too often, SCAD patients get other diagnoses and are sent home from the emergency department because the patients are young and do not have the atherosclerotic risk factors that would prompt workup for MI, or the condition gets managed as atherosclerotic ACS, "which may harm patients with SCAD," the team said.
It's only recently that evidence has developed to counter the traditional medical school teaching that this is an incredibly rare condition that should be worked up with an angiogram, Hayes told ľֱ in an interview.
"There's been a sea change in our understanding of this condition over the past 7 or 8 years. Wow, we were missing it all these years. And people are still missing it."
The statement included an algorithm for management, focusing on when to consider invasive measures, which is notably different from what is done for atherosclerotic forms of coronary artery disease.
"Once SCAD is suspected, coronary angiography should be performed as early as feasible, especially in the setting of ST-segment-elevation MI," the team urged. This imaging modality isn't very good at diagnosing SCAD but remains first-line due to wide availability and the role for the minority of SCAD patients who will need early invasive management.
The best data available, from observational angiographic studies, suggest that the dissections heal in up to 70-97% of those patients restudied in the weeks to months after being conservatively managed initially.
About 5-10% of conservatively managed patients have early complications of recurrent MI, mostly related to extension of dissection within the first week and most of whom require emergency revascularization, Hayes et al wrote. Because of that risk, inpatient monitoring for 3 to 5 days is typically recommended as part of a conservative strategy.
While conservative strategies might not be appropriate for high-risk patients with ongoing ischemia, left main artery dissection, or hemodynamic instability -- they need urgent percutaneous or surgical intervention, according to the statement -- stenting in SCAD is riskier. Studies have reported technical failure in 27-36% of patients, and a need for emergency bypass surgery as a complication in 9-12%.
"This is the first statement that pulls all of that data from the international collection where there's been a growth in our knowledge but it hasn't been put together anywhere," Hayes concluded. "Much of the research that has been published over the past 7 or 8 years is hypothesis generating less than answering the questions. I hope this spurs many other people to properly diagnose their patients, to properly treat them, and to take the science to next level."
Disclosures
Hayes disclosed no relevant relationships with industry.
The authors noted that the creation of one of the figures used in the paper was supported financially by the family of Ann Fensterwald Eisenstein.
Primary Source
Circulation
Hayes SN, et al "Spontaneous Coronary Artery Dissection: Current State of the Science: A Scientific Statement from the American Heart Association" Circulation 2018; DOI: 10.1161/CIR.0000000000000564.