Abstract 2684: Perfusion Abnormalities Detected by Myocardial Contrast Echocardiography in Patients With Coronary Ectasia in the Absence of Significant Stenosis
Background/aim: Coronary ectasia has been correlated in the past to decreased coronary blood flow velocity. However, its impact on myocardial perfusion has not been adequately evaluated. The goal of this study was to assess myocardial perfusion in patients with ectatic coronary arteries, using stress-contrast echocardiography .
Methods: 25 subjects (10 females, age 67 ± 7) with ectatic coronary segments shown on coronary angiography (CAG) - with ectasia defined as vessel diameter >1.5 times the diameter of adjacent arterial segments - without stenoses >50% and 20 controls with normal coronary arteries (matched for age, sex, presence of diabetes, smoking history and dyslipidemia) were submitted to dobutamine stress echocardiography (four-staged protocol with atropine as required to achieve 90% of target heart rate). Concurrent myocardial contrast echocardiography (MCE) study was performed (Sonovue, Bracco) with a Sonos 5500 (Philips Medical Systems) machine. The acquired images were reviewed by two experienced readers, who were blinded to the angiographic findings.
Results : Among patients with ectasia, all had normal perfusion studies at rest, while 21 (84%) showed a reversible perfusion defect at peak stress. On the contrary, only 4 (20%) (p<0.01) of the controls showed a reversible perfusion defect on MCE. The location of the perfusion defects in each patient with coronary ectasia were then compared with the distribution of the artery(ies) with the ectatic segment(s). The observed perfusion defect on MCE corresponded to a coronary artery with ectatic segment(s) in 19 out of the 21 patients with coronary ectasia and perfusion defects on MCE, which means that in 19 out of 25 (76%) patients with ectatic coronary artery segments, the myocardial regions supplied by the ectatic vessels showed impaired perfusion at stress, demonstrable by MCE.
Conclusions: Our findings suggest that ectatic coronary arteries commonly cause significant myocardial ischemia on stress, as shown by MCE, in the absence of significant stenoses on CAG. This may be taken into account in the clinical evaluation of these patients and may explain the manifestation of symptoms of ischemia in subjects with non-stenosed, albeit ectatic, coronary arteries.