Spontaneous Coronary Dissection
Computed Tomography Appearance and Insights From Intravascular Ultrasound Examination
A 47-year-old woman with hypertension and a family history of coronary artery disease presented to the Emergency Department with chest pain that radiated to the left arm. ECG demonstrated T-wave inversion in leads V1 to V3, which was associated with an elevated troponin I value of 4.7 ng/mL. An angiogram performed on the same day (Figure 1, Movie I) showed a narrowing of the entire left anterior descending coronary artery (LAD), which was unresponsive to nitroglycerin infusion. On the basis of her medical history and because of the diffuse narrowing, a spontaneous coronary dissection was suspected, although no flap could be seen. Because the patient’s condition was stable, medical management was instituted with aspirin, clopidogrel, a β-blocker, and an angiotensin-converting enzyme inhibitor, together with coumarin for left ventricular thrombus protection. A 16-slice computed tomography examination performed on day 6 showed a double-lumen aspect in cross-section at the lesion site, compatible with the presence of a false and a true lumen (Figure 2). On day 7, the patient presented with a recurrence of the chest pain and a new troponin elevation of 5.6 ng/mL. Angiography at that time (Figure 3, Movie II) confirmed the etiology of spontaneous coronary dissection, with intense contrast staining in the LAD and delayed filling of the artery (TIMI grade 2 flow). The decision was made to perform a percutaneous coronary intervention guided by intravascular ultrasound (IVUS). IVUS examination (Figure 3, Movie III) showed the dissection with a true lumen compressed by an extensive false lumen filled with hematoma and contrast dye. Importantly, IVUS allowed us to confirm that the guidewire was located in the true lumen. Three stents were successfully implanted (Figure 4) with a good angiographic result. The later course of the patient was uneventful, with regression of cardiac biomarkers.
Spontaneous dissection of the coronary arteries is rare and is more prevalent in young women, particularly in the peripartum period. Percutaneous coronary intervention is the treatment of choice in patients with ongoing ischemia when the left main coronary artery is not involved. However, because of the risk of stenting the false lumen that would occlude the artery, the position of the guidewire in the true lumen is of major importance. This case clearly demonstrates the utility of IVUS imaging in the diagnosis of coronary dissection and in the ascertainment of the proper position of the guidewire in the true lumen.
The online-only Data Supplement, which contains 3 movies, can be found at http://circ.ahajournals.org/cgi/content/full/113/10/e403/DC1.