High resting coronary flow velocity predicts worse survival in chronic coronary syndromes. (3rd October 2022) - Ciampi, Q
Abstract: Background: Coronary flow velocity (CFV) in the mid-distal left anterior descending coronary artery (LAD) can be easily assessed with transthoracic echocardiography (TTE). Although high resting CFV is associated with a reduced coronary flow velocity reserve which is a predictor of poor outcome, the prognostic significance of resting CFV remains unknown. Aim: To assess the relationship between resting CFV and outcome. Methods: Out of 11, 410 initially screened, we prospectively enrolled 10, 023 patients (age 64±12 years, 5, 902 men, left ventricular ejection fraction [LVEF] 58±10%) with chronic coronary syndromes referred for resting TTE and with interpretable CFV. Recruitment (years 2004–2020) involved 5 accredited laboratories, with inter-observer variability <10% for CFV at study entry. Baseline peak diastolic CFV was obtained by pulsed-wave Doppler in mid-distal LAD. All-cause death was the only end-point. Results: The feasibility of CFV was 95%. The mean CFV of LAD was 32±14 cm/s. By multivariable logistic regression analysis diabetes mellitus, prior myocardial infarction, lower LVEF and higher age, heart rate, and systolic blood pressure were associated with the highest quintile of CFV. During a mean follow-up of 4.6±3.7 years, 1, 066 died. Mortality at 10-years was lowest (15%) in patients in the lowest quintile (≤24 cm/s) and highest (34%) in patients in the highest (≥38 cm/s) quintile of CFV. Age (HR 1.057, 95% CI 1.053–1.062; p<0.0001), diabetes mellitus (HR 1.845, 95% CI 1.573–2.164; p<0.0001), prior coronary surgery (HR 1.350, 95% CI 1.064–1.712; p=0.01), LVEF (HR 0.973, 95% CI 0.963–0.982; p<0.0001), the 4th quintile (HR 1.267, 95% CI 1.010–1.589; p=0.04), and the 5th quintile of CFV of LAD (HR 1.311, 95% CI 1.040–1.652; p=0.02) independently predicted mortality. At incremental analysis, CFV of LAD added prognostic information to clinical findings and LVEF. Conclusion: CFV imaging in mid-distal LAD is highly feasible with TTE. High resting CFV predicts worse survival in the long-term. Funding Acknowledgement: Type of funding sources: None.