Elevated tricuspid peak systolic gradient with enlarged right ventricle present during acute episode of pulmonary embolism predict subsequent chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disease with poor outcome if left untreated. Identifying patients at risk of CTEPH already at acute pulmonary embolism (APE) would lead to earlier goal-directed management. Since echocardiography is frequently performed during APE we aimed to assess its predictive value for subsequent CTEPH. During follow up all symptomatic patients underwent diagnostic workup for CTEPH. Echocardiographic parameters recorded during the APE episode were analyzed for subsequent CTEPH. The study included 625 patients (345 F, age 60.36 ± 17.71), 25 subjects (4%) (12 F; age 62.9 ± 18.8), were diagnosed with CTEPH. Patients with CTEPH presented at APE diagnosis more severe echocardiographic signs of right ventricular (RV) pressure overload. Multivariate analysis revealed that only tricuspid regurgitation peak gradient (TRPG), (OR = 1.05 CI95[1.03; 1.08], p < 0.001) and RV to left ventricle ratio (RV/LV), (OR = 9.86 CI95[2.26; 43.56], p = 0.002) were significant predictors of CTEPH. ROC analysis of TRPG for the diagnosis of CTEPH had AUC = 0.792 CI95[0.683-0.900], while RV/LV 0.777 CI95[0.675–0.878]. Combination of RV/LV ≥ 1.14 and TRPG ≥ 44mmHg (tricuspid regurgitation velocity (TRV) ≥ 3.3 m/s) present in 8.1% of patients identified high risk category of subsequent CTEPH with CTEPH incidence of 28.2% CI95[15.0-44.9%] (sensitivity 47.8% CI95[26.8–69.4%], specificity 93.9% CI95[91.3–95.9%], NPV 97.3% CI95[96.0-98.1%], PPV 28.2% CI95[18.4–40.7%]). TRPG < 44mmHg (TRV < 3.3 m/s) with RV/LV ratio < 1.14 present 66.7% of studied patents formed low risk group with CTEPH incidence of 1.6% CI95 [0.5–3.6%] (sensitivity 21.7% CI95 [7.5–43.7%], specificity 31.1% CI95 [26.9–35.5%]. Combination of TRPG ≥ 44mmHg (TRV ≥ 3.3 m/s) with RV/LV ≥ 1.14 present at echocardiography during acute PE identifies patients at high risk of subsequent CTEPH and our opinion warrants their active screening for CTEPH.