Discontinuous Doppler-Derived Intrarenal Venous Flow Is a Predictor of Impaired Exercise Capacity Associated With Poor Prognosis in Patients With Acute Coronary Syndrome

Abstract

Background

Doppler-derived intrarenal venous flow (IRVF) has recently been used to assess renal congestion and intrarenal hemodynamics. Although several reports suggest that IRVF is useful for predicting the prognosis of patients with heart failure (HF), information is sparse for patients with acute coronary syndrome (ACS). Therefore, we performed a study to investigate the relationship between IRVF and peak oxygen consumption (VO₂), which is associated with prognosis in patients with ACS.

Methods and Results

We enrolled 80 patients with ACS. The prevalence of discontinuous IRVF (DIRVF) was higher in patients with peak VO₂ less than the group median (13.2 mL/min/kg; 38% vs. 8%, p = 0.003). Multivariable logistic regression analyses indicated that DIRVF was the only independent predictor of peak VO₂ <12 mL/min/kg (odds ratio 6.33, 95% confidence interval [CI] 1.28−31.1, p = 0.02). Median follow-up was 366 days [189−513 days]. The occurrence of composite endpoints, including death from cardiovascular disease and unplanned hospitalization for HF, was significantly higher in patients with DIRVF than in those with continuous IRVF (p = 0.001). Moreover, according to receiver operating characteristic curves, the area under the curve obtained with basic clinical variables (age, sex, and log N-terminal pro-B-type-natriuretic peptide) was 0.72 (95% CI 0.60−0.83); this increased significantly to 0.84 (95% CI 0.75−0.93) when peak early diastolic mitral inflow velocity to early diastolic velocity ratio (E/e’) and DIRVF were added (p = 0.007).

Conclusions

DIRVF predicts impaired exercise capacity, which is associated with poor prognosis, in patients with ACS.