Clinical, hemodynamic, and functional variables affecting success rate of coronary flow velocity reserve detection during vasodilator stress echocardiography.

AIM: Stress echocardiography (SE) with state-of-the-art imaging protocol allows a comprehensive assessment of regional wall-motion abnormalities and Doppler-based coronary flow velocity reserve (CFVR) in left anterior descending artery (LAD). We sought to assess the variables potentially impacting on success rate of SE with CFVR.

METHODS AND

RESULTS

In a single-center, prospective, observational study design, from 2007 to 2019, we enrolled 2989 consecutive patients (age 67 ± 12 years; 1723 men) referred for SE, without contrast, for chronic known (n = 1130) or suspected (n = 1859) coronary syndromes. Coronary flow velocity reserve was measured as stress/rest peak diastolic flow velocity. The same operator (LC) performed all examinations with the same machine (GE Vivid 7). Interpretable CFVR was obtained in 2808 patients (feasibility = 93.9%). Overall success rate was lowest (91.4%) in 2007-2008 and steadily rose to 97.8% in 2017-2019 (P for trend <.0001). Feasibility was excellent for men (93.7%) and women (94.3%) (P = .47) across all values of body mass index (BMI): <25 (P = .09), 25-29 (P = .84), and ≥30 (P = .23). At multivariable logistic regression analysis, women with BMI ≥ 30 (OR 1.94, 95% CI 1.14-3.29, P = .02), resting heart rate ≥77 beats/min (OR 2.25, 95% CI 1.64-3.11; P < .0001), and stress-induced ischemia in the LAD territory (OR 3.14, 95% CI 1.67-5.90; P < .0001) predicted unfeasible CFVR.

CONCLUSION

Vasodilator SE with CFVR combined with wall-motion analysis is highly feasible also without contrast although with a slight decline in presence of high resting heart rate (reducing diastolic time essential for flow imaging), women with BMI ≥ 30 (increasing tissue thickness interposed between transducer and artery), and anterior ischemia (for underlying low-absent anterograde flow for severely stenotic or occluded LAD).