ACCELERATED STENOTIC FLOW IN THE LEFT ANTERIOR DESCENDING CORONARY ARTERY DETECTED BY ENHANCED TRANSTHORACIC DOPPLER PREDICTS PLAQUE BURDEN

Background: It is well known that an atherosclerotic plaque burden (PB) in coronaries shown by intracoronary ultrasound (IVUS) can predict severe coronary events. Stenosis, even mild, (concentric remodeling) follows on from an atherosclerosis eccentric plaque, further incrementing the atherosclerotic burden. We hypothesized that detecting stenosis, even mild, on the basis of increased flow velocity (velocity increment/reference velocity*100) in the left anterior descending coronary artery (LAD), reliably assessed by convergent color Doppler echocardiography (E-Doppler TTE), may predict PB as detected by IVUS. Methods: Ninety-six consecutive pts scheduled for IVUS underwent E-Doppler TTE; accelerated stenotic flows (ASF) in the entire LAD, when observed, were plotted vs the mean proximal and mid LAD PB. PB was categorized in 4 groups of severity (see graph). Results: Overall, there was a strong correlation between PB and ASF (r= 0.7, p< 0.001) and the missed PBs by ASF were only those with less severity (group 2). The sensitivity and specificity in detecting at least a mild PB were 88% and 95% with a 20% increased velocity cutoff; an increase by >120% mostly demonstrated moderate and severe PB (see graph). Conclusion: Not only can E-Doppler TTE detect stenosis (from mild to severe) but the severity of the stenosis expressed by the ASF is predictive of PB as quantified by IVUS. This can provide an important clinical insight impacting therapy (changing lifestyle to offset atherosclerosis) and prognosis.