Perspective:

Michelis and colleagues review the coronary artery manifestations of fibromuscular dysplasia (FMD) in this article. This is an uncommon, but increasingly recognized disease in the cardiac cath lab. It is important for both general cardiologists and interventional cardiologists to become familiar with its key aspects. The following are five take-home points from this review:

1. Think about FMD in the coronary artery when you see an acute coronary syndrome (ACS) or episode of sudden cardiac death in patients without other manifestations or risk factors for coronary artery disease. It can happen in all age groups and both genders, but young and middle-aged women are particularly susceptible.

2. An affected coronary artery does not look like a ‘string of beads’ as in other vascular territories, but can appear as a dissection, smooth narrowing of a distal vessel, intramural hematoma, or tortuosity. The key manifestation of FMD in the coronary artery is spontaneous coronary artery dissection (SCAD) of an epicardial or major branch that leads to ACS.

3. In order to label a patient with FMD and coronary artery manifestations, visualization of FMD must be confirmed in other territories. Cross-sectional imaging from head-to-pelvis is recommended, typically with computed tomography scanning to identify abnormal arterial structures, including aneurysms or dissections, in other vessels.

4. Differential diagnosis should include: Ehlers-Danlos type IV, arteritis of the coronary artery (Takayasu’s or giant cell), cocaine use, coronary artery spasm, myocardial bridging, standing waves, and of course, atherosclerotic coronary artery disease.

5. Treatment is largely experience-based with no randomized clinical trials. Conservative management seems most appropriate for patients even in the setting of SCAD, unless unstable symptoms prompt early intervention. Conservative management is best since most dissections appear to heal on their own and the risk of percutaneous coronary intervention is high in these patients due to propagation of the dissection and other procedural complications.