Coronary Flow Velocity Reserve Using Dobutamine Test for Noninvasive Functional Assessment of Myocardial Bridging

Srdjan B Aleksandric; Ana D Djordjevic-Dikic; Vojislav L Giga; Milorad B Tesic; Ivan A Soldatovic; Marko D Banovic; Milan R Dobric; Vladan Vukcevic; Miloje V Tomasevic; Dejan N Orlic; Nikola Boskovic; Ivana Jovanovic; Milan A Nedeljkovic; Goran Stankovic; Miodrag C Ostojic; Branko D Beleslin

doi:10.3390/jcm11010204

Coronary Flow Velocity Reserve Using Dobutamine Test for Noninvasive Functional Assessment of Myocardial Bridging

J Clin Med. 2021 Dec 30;11(1):204. doi: 10.3390/jcm11010204.

Authors

Srdjan B Aleksandric^{1

2}, Ana D Djordjevic-Dikic^{1

2}, Vojislav L Giga^{1

2}, Milorad B Tesic^{1

2}, Ivan A Soldatovic^{2

3}, Marko D Banovic^{1

2}, Milan R Dobric^{1

2}, Vladan Vukcevic^{1

2}, Miloje V Tomasevic^{1

4}, Dejan N Orlic^{1

2}, Nikola Boskovic¹, Ivana Jovanovic¹, Milan A Nedeljkovic^{1

2}, Goran Stankovic^{1

2}, Miodrag C Ostojic^{2

5}, Branko D Beleslin^{1

2}

Affiliations

¹ Cardiology Clinic, University Clinical Center of Serbia, 11000 Belgrade, Serbia.
² Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia.
³ Institute of Medical Statistics and Informatics, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia.
⁴ Department of Internal Medicine, Faculty of Medical Sciences, University of Kragujevac, 34000 Kragujevac, Serbia.
⁵ Institute for Cardiovascular Diseases Dedinje, 11000 Belgrade, Serbia.

Abstract

Background: It has been shown that coronary flow velocity reserve (CFVR) measurement by transthoracic Doppler echocardiography (TTDE) during dobutamine (DOB) provocation provides a more accurate functional evaluation of myocardial bridging (MB) compared to adenosine. However; the cut-off value of CFVR during DOB for identification of MB associated with myocardial ischemia has not been fully clarified.

Purpose: This prospective study aimed to determine the cut-off value of TTDE-CFVR during DOB in patients with isolated-MB, as compared with stress-induced wall motion abnormalities (VMA) during exercise stress-echocardiography (SE) as reference.

Methods: Eighty-one symptomatic patients (55 males [68%], mean age 56 ± 10 years; range: 27-74 years) with the existence of isolated-MB on the left anterior descending artery (LAD) and systolic MB-compression ≥50% diameter stenosis (DS) were eligible to participate in the study. Each patient underwent treadmill exercise-SE, invasive coronary angiography, and TTDE-CFVR measurements in the distal segment of LAD during DOB infusion (DOB: 10-40 μg/kg/min). Using quantitative coronary angiography, both minimal luminal diameter (MLD) and percent DS at MB-site at end-systole and end-diastole were determined.

Results: Stress-induced myocardial ischemia with the occurrence of WMA was found in 23 patients (28%). CFVR during peak DOB was significantly lower in the SE-positive group compared with the SE-negative group (1.94 ± 0.16 vs. 2.78 ± 0.53; p < 0.001). ROC analyses identified the optimal CFVR cut-off value ≤ 2.1 obtained during high-dose dobutamine (>20 µg/kg/min) for the identification of MB associated with stress-induced WMA, with a sensitivity, specificity, positive and negative predictive value of 96%, 95%, 88%, and 98%, respectively (AUC 0.986; 95% CI: 0.967-1.000; p < 0.001). Multivariate logistic regression analysis revealed that MLD and percent DS, both at end-diastole, were the only independent predictors of ischemic CFVR values ≤2.1 (OR: 0.023; 95% CI: 0.001-0.534; p = 0.019; OR: 1.147; 95% CI: 1.042-1.263; p = 0.005; respectively).

Conclusions: Noninvasive CFVR during dobutamine provocation appears to be an additional and important noninvasive tool to determine the functional severity of isolated-MB. A transthoracic CFVR cut-off ≤2.1 measured at a high-dobutamine dose may be adequate for detecting myocardial ischemia in patients with isolated-MB.

Keywords: coronary flow velocity reserve; dobutamine; myocardial bridging; myocardial ischemia; stress-echocardiography; transthoracic Doppler echocardiography.