Right ventricular-pulmonary artery coupling for prognostication in acute pulmonary embolism

Background: Acute pulmonary embolism (PE) increases pulmonary pressure and impair right ventricular (RV) function. Echocardiographic investigation can quantify this mismatch as the tricuspid annular plane systolic excursion (TAPSE) to pulmonary arterial systolic pressure (PASP) ratio. The aim of the study was to investigate the prognostic capabilities of TAPSE/PASP ratio in patients with acute PE.

Methods: We utilized the RIETE registry to analyze consecutive hemodynamically stable PE patients. We used multivariable logistic regression analyses to assess the association between the TAPSE/PASP ratio and 30-day all-cause mortality across the strata of European Society of Cardiology (ESC) risk categories.

Results: We included 4,478 patients, of whom 1,326 (30%) had low-risk, 2,425 (54%) intermediate-low risk, and 727 (16%) intermediate-high risk PE. Thirty-day mortality rates were 0.7%, 2.3% and 3.4%, respectively. Mean TAPSE/PASP ratio was 0.65±0.29 in low-risk patients, 0.46±0.30 in intermediate-low risk, and 0.33±0.19 in intermediate-high risk patients. In multivariable analyses, there was an inverse association between TAPSE/PASP ratio and 30-day mortality (adjusted OR 1.32 [95%CI 1.14-1.52] per 0.1 decrease in TAPSE/PASP). TAPSE/PASP ratio below optimal cut-points was associated with increased mortality in low- (<0.40, aOR: 5.88; 95%CI:1.63-21.2), intermediate-low (<0.43, aOR: 2.96; 95%CI:1.54-5.71) and intermediate-high risk patients (<0.34, aOR: 4.37; 95%CI:1.27-15.0). TAPSE/PASP <0.44 showed net reclassification improvement of 18.2% (95%CI:0.61-35.8) vs. RV/LV ratio >1, and 27.7% (95%CI:10.2-45.1) vs. ESC risk strata.

Conclusions: Decreased TAPSE/PASP ratio was associated with increased mortality. The ratio may aid in clinical decision-making, particularly for intermediate-risk patients for whom the discriminatory capability of the current risk stratification tools is limited.