Frequency and characterization of CTEPH and CTEPD according to the mPAP threshold > 20 mm Hg: Retrospective analysis from data of a prospective PE aftercare program.

BACKGROUND: The influence of the new pulmonary hypertension (PH) definition on the incidence of chronic thromboembolic PH (CTEPH) is unclear. The incidence of chronic thromboembolic pulmonary disease without PH (CTEPD) is unknown. OBJECTIVES: To determine the frequency of CTEPH and CTEPD using the new mPAP cut-off >20 mmHg for PH in patients who have suffered an incidence of pulmonary embolism (PE) and were recruited into an aftercare program. METHODS: In a prospective two-year observational study based on telephone calls, echocardiography and cardiopulmonary exercise tests, patients with findings suspicious for PH received an invasive work-up. Data from right heart catheterization were used to identify patients with or without CTEPH/CTEPD. RESULTS: Two years after acute PE (n = 400) we found an incidence of 5.25% for CTEPH (n = 21) and 5.75% for CTEPD (n = 23) according to the new mPAP threshold >20 mmHg. Five of 21 patients with CTEPH and 13 of 23 patients with CTEPD showed no signs of PH in echocardiography. CTEPH and CTEPD subjects showed a reduced VO2 peak and work rate in cardiopulmonary exercise testing (CPET). The capillary end-tidal CO2 gradient was comparably elevated in CTEPH and CTEPD, but it was normal in the Non-CTEPD-Non-PH group. According to the PH definition provided by the former guidelines, only 17 (4.25%) patients have been diagnosed with CTEPH and 27 individuals (6.75%) were classified having CTEPD. CONCLUSIONS: Using mPAP >20 mmHg for diagnosis of CTEPH leads to an increase of 23.5% of CTEPH diagnosis. CPET may help to detect CTEPD and CTEPH.

Prognostic Relevance of Cardiopulmonary Exercise Testing for Patients with Chronic Thromboembolic Pulmonary Hypertension.

Background: Following acute pulmonary embolism (PE), a relevant number of patients experience decreased exercise capacity which can be associated with disturbed pulmonary perfusion. Cardiopulmonary exercise testing (CPET) shows several patterns typical for disturbed pulmonary perfusion. Research question: We aimed to examine whether CPET can also provide prognostic information in chronic thromboembolic pulmonary hypertension (CTEPH). Study Design and Methods: We performed a multicenter retrospective chart review in Germany between 2002 and 2020. Patients with CTEPH were included if they had ≥6 months of follow-up and complete CPET and hemodynamic data. Symptom-limited CPET was performed using a cycle ergometer (ramp or Jones protocol). The association of anthropometric data, comorbidities, symptoms, lung function, and echocardiographic, hemodynamic, and CPET parameters with survival was examined. Mortality prediction models were calculated by Cox regression with backward selection. Results: 345 patients (1532 person-years) were included; 138 underwent surgical treatment (pulmonary endarterectomy or balloon pulmonary angioplasty) and 207 received only non-surgical treatment. During follow-up (median 3.5 years), 78 patients died. The death rate per 1000 person-years was 24.9 and 74.2 in the surgical and non-surgical groups, respectively (p < 0.001). In age- and sex-adjusted Cox regression analyses, CPET parameters including peak oxygen uptake (VO2peak, reflecting cardiopulmonary exercise capacity) were prognostic in the non-surgical group but not in the surgical group. In mortality prediction models, age, sex, VO2peak (% predicted), and carbon monoxide transfer coefficient (% predicted) showed significant prognostic relevance in both the overall cohort and the non-surgical group. In the non-surgical group, Kaplan−Meier analysis showed that patients with VO2peak below 53.4% predicted (threshold identified by receiver operating characteristic analysis) had increased mortality (p = 0.007). Interpretation: The additional measurement of cardiopulmonary exercise capacity by CPET allows a more precise prognostic evaluation in patients with CTEPH. CPET might therefore be helpful for risk-adapted treatment of CTEPH.

Impact of the new definition of pulmonary hypertension according to world symposium of pulmonary hypertension 2018 on diagnosis of post-capillary pulmonary hypertension.

BACKGROUND: The World Symposium on Pulmonary Hypertension (WSPH) in 2018 recommended new definitions of pulmonary hypertension (PH). We investigated the impact of the updated definition on prevalence of PH due to left heart disease (PH-LHD). METHODS: The data of right heart catheterizations in patients with suspected PH-LHD between January 2008 and July 2015 was retrospectively analyzed applying different definitions. The number of patients diagnosed by the updated WSPH hemodynamic criteria of a mean pulmonary artery pressure (mPAP) > 20 mmHg was compared to the number of patients using mPAP ≥ 25 mmHg. The differentiation between patients with isolated post-capillary (Ipc) and combined post-capillary and pre-capillary (Cpc) PH was analyzed comparing the ESC/ERS guidelines, the recommendation of Cologne Consensus Conference (CCC) and WSPH. RESULTS: Of the 726 patients with a suspected PH, 58 patients met the diagnostic criteria of the ESC/ERS guidelines for PH-LHD with 32.8% Ipc-cases, 34.4% Cpc-PH-cases and 32.8% unclassifiable cases. Overall, 58 patients were diagnosed by the CCC criteria, with 34.5% classified as Cpc-PH and 65.5% as Icp-PH. Using the criteria of WSPH, the number of PH-LHD rose by one patient. According to the new definition, 64.4% of the patients were classified as Cpc-PH and had a significantly higher right to left atrial area (RA/LA) ratio than Ipc-PH patients. CONCLUSION: Applying the new recommendation, the number of diagnosed patients with PH-LHD increases marginally. There is, however, a relevant shift in the number of Cpc-PH cases. An elevated RA/LA ratio might help to identify patients for invasive diagnostic work-up.