Martin de Miguel I; Hospital Universitario 12 de Octubre, Madrid, Spain;
Jimenez Lopez-Guarch C; Segura de La Cal T; Huertas
Nieto S; Sarnago Cebada F; Velazquez Martin M; Maneiro Melon N; Cruz
Utrilla A; Biscotti Rodil B; Gutierrez-Ortiz E; Arribas Ynsaurriaga F;
Escribano Subias P

Chest. 169(3):769-783, 2026 Mar.

BACKGROUND: Chronic thromboembolic pulmonary disease corresponds to
exercise impairment after a pulmonary embolism due to persistent chronic
thrombi and exercise pulmonary hypertension (PH). Diagnosis requires
exercise right heart catheterization (RHC), whereas data on noninvasive
diagnosis are scarce.

RESEARCH QUESTION: Is there an association between noninvasive parameters
and exercise PH among symptomatic patients with chronic thromboembolism?

STUDY DESIGN AND METHODS: Data come from a prospective cohort of 92
patients with chronic thrombi and absence/only mild resting PH undergoing
cardiopulmonary exercise testing and exercise RHC with concomitant
echocardiography. Clinical, functional, imaging, and hemodynamic data were
documented. Exercise PH was defined as mean pulmonary artery
pressure/cardiac output slope > 3 mm Hg/L/min.

RESULTS: The mean age of the patients was 52.7 +/- 14.3 years, and 62.0%
were male. A total of 37 patients (40.2%) developed exercise PH. Patients
with exercise PH had lower peak oxygen consumption, lower peak exercise
oxygen saturation, and higher ventilatory inefficiency. At rest and peak
exercise, they had higher tricuspid regurgitation peak velocity (TRPV),
lower tricuspid annular plane systolic excursion (TAPSE)/pulmonary artery
systolic pressure (PASP) ratio, invasively higher pulmonary pulse
pressure, and lower pulmonary artery compliance. Peak exercise aortic
saturation, peak oxygen consumption, partial pressure of end-tidal CO2 at
first ventilatory threshold, TRPV, and TAPSE/PASP ratio were independent
predictors of exercise PH. Two weighted risk scores including age, partial
pressure of end-tidal CO2 at first ventilatory threshold, and peak TRPV or
peak TAPSE/PASP identified patients at low vs high risk of exercise PH.

INTERPRETATION: Our results show that symptomatic patients with chronic
thrombi and exercise PH had impaired right ventricular contractile reserve
and augmented afterload assessed by cardiopulmonary exercise testing,
exercise echocardiography, and exercise RHC. Two noninvasive
multiparametric scores aided stratification of low vs high risk of
exercise PH.