Evaluation of coronary artery abnormalities in Williams syndrome patients using myocardial perfusion scintigraphy and CT angiography.

Background: Sudden death risk in Williams syndrome (WS) patients has been shown to be 25-100 times higher than in the general population. This study aims to detect coronary artery anomalies and myocardial perfusion defects in WS patients using noninvasive diagnostic methods.

Methods: This study features 38 patients diagnosed with WS. In addition to physical examination, electrocardiography, and echocardiography, computed tomography (CT) angiography and rest/dipyridamole stress technetium-99m sestamibi ((99m)Tc-sestamibi) single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy (MPS) were performed.

Results: Twenty-one (55%) patients were male; 17 (45%) were female. The average patient age was 12 ± 5 years (2.5-26 years); the average follow-up period was 7.2 ± 4.2 years (6 months-18 years). Cardiovascular abnormalities were found in 89% of patients, the most common one being supravalvar aortic stenosis (SVAS). CT angiography revealed coronary anomalies in 10 (26%) patients, the most common ones being ectasia of the left main coronary artery and proximal right coronary artery as well as myocardial bridging. SVAS was present in 80% of patients with coronary artery anomalies. (99m)Tc-sestamibi SPECT MPS revealed findings possibly consistent with myocardial ischemia in 29% of patients, and ischemia in 7 out of 10 patients (70%) with coronary anomalies shown on CT angiography (p = 0.03).

Conclusions: Coronary artery abnormalities are relatively common in WS patients and are often accompanied by SVAS. CT angiography and dipyridamole (99m)Tc-sestamibi SPECT MPS seem to be less invasive methods of detecting coronary artery anomalies and myocardial perfusion defects in WS patients.