Incremental Prognostic Value of Left Ventricular Outflow Tract Velocity Time Integral (LVOT VTI) Beyond Ejection...

Left ventricular ejection fraction (LVEF) is a widely used echocardiographic prognostic marker; however, its ability to reflect forward flow is limited. Left ventricular outflow tract velocity time integral (LVOT VTI) reflects stroke distance and has prognostic value in patients with cardiac and non-cardiac pathology, yet its incremental value beyond LVEF remains incompletely defined.

To determine whether LVOT VTI confers prognostic value beyond LVEF in a large real-world cohort of hospitalized patients.

Index echocardiograms performed between January and June 2021 at a single tertiary hospital were retrospectively analyzed. Demographics, echocardiographic parameters, biomarkers, and mortality data were collected. Patients were stratified by LVOT VTI (>13 and <13 cm) and LVEF (>40% and <40%). Associations with mortality were evaluated with Cox proportional hazard models.

Altogether, 1325 patients (mean age 70 years) were included; 368 (28%) died over a median follow-up of 35.9 months (IQR 34.4-37.4). Both LVEF < 40% (HR 1.95, 95% CI 1.52-2.50; p < 0.001) and LVOT VTI < 13 cm (HR 1.91, 95% CI 1.41-2.59; p < 0.001) were associated with increased mortality. LVOT VTI < 13 cm remained predictive after adjustment for LVEF, although this was attenuated after adjustment for age. Mortality was greatest in patients with both LVEF < 40% and LVOT VTI < 13 cm (HR 2.37, 95% CI 1.63-3.46; p  < 0.001).

LVOT VTI < 13 cm is independently associated with long-term mortality in hospitalized patients. Its incremental prognostic value beyond LVEF warrants prospective validation as a reproducible marker to enhance risk stratification in hospitalized patients.