[Cardiopulmonary exercise testing in exercise-induced pulmonary hypertension]

Area of Science:

• Pulmonary Medicine
• Cardiology
• Exercise Physiology

Background:

• Cardiopulmonary exercise-testing (CPET) is crucial for diagnosing exertional breathlessness.
• Exercise-induced pulmonary hypertension (EIPH) is a recognized cause of exertional dyspnea.
• Specific CPET indicators for EIPH remain unclear.

Purpose of the Study:

• To assess the accuracy of CPET in identifying EIPH.
• To elucidate CPET characteristics associated with EIPH.

Main Methods:

• Prospective study of 39 patients with exertional breathlessness undergoing CPET and exercise echocardiography.
• Patients categorized into controls, EIPH, and resting pulmonary hypertension (PH) groups.
• Analysis of CPET parameters, including VD/VT and P[a-ET]CO2, in each group.

Main Results:

• Patients with EIPH showed significantly higher VD/VT and P[a-ET]CO2 at peak exercise compared to controls.
• A peak exercise VD/VT ratio > 0.34 demonstrated 72.7% sensitivity and 71% specificity for predicting EIPH.
• Elevated VD/VT and P[a-ET]CO2 were also observed in patients with resting PH.

Conclusions:

• EIPH is associated with a failure to decrease or an increase in dead space during exercise.
• CPET is a valuable tool for identifying patients who may benefit from further invasive hemodynamic assessment for EIPH.