Background: Stroke distance of the left ventricular outflow tract (LVOT) or pulmonary artery (PA) is readily measurable by Doppler echocardiography. Stroke distance, calculated by the velocity time integral, expresses the average linear distance traveled by red blood cells during systole. We hypothesized that reduced stroke distance predicts heart failure (HF) hospitalization or mortality among ambulatory adults with stable coronary artery disease.
Methods: We compared stroke distances by lowest quartile among 990 participants in the Heart and Soul Study. We calculated hazard ratios (HRs) for events adjusted for clinical and echocardiographic parameters.
Results: At 5.9 ± 1.9-year follow-up, there were 154 HF hospitalizations and 271 all-cause deaths. Among 254 participants with LVOT stroke distance in the lowest quartile (≤ 18 cm), 24% developed HF hospitalization, compared with 10% of those with higher stroke distance (HR 2.7; CI, 2.0-3.8; P < .0001). This association remained after adjustment for multiple variables including medical history, heart rate, blood pressure, and left ventricular ejection fraction (HR 1.8; CI, 1.1-3.0; P = .02). Both LVOT stroke distance ≤ 18 cm and PA stroke distance ≤ 17 cm were independently associated with the combined end point of HF hospitalization and mortality (HR 1.4; CI, 1.1-1.9; P = .02).
Conclusion: Reduced stroke distance predicts HF hospitalization and mortality independent of clinical and other echocardiographic parameters among ambulatory adults with coronary artery disease.
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