Chronic Thromboembolic Pulmonary Disease Phenotypes Using Upright Invasive Cardiopulmonary Exercise Testing.

Area of Science:

• Cardiology
• Pulmonary Medicine
• Exercise Physiology

Background:

• Patients with chronic thromboembolic pulmonary disease (CTEPD) often experience unexplained dyspnea.
• Standard assessments may not fully explain exertional dyspnea in CTEPD patients.
• Cardiopulmonary exercise testing (CPET) is crucial for further diagnostic insight.

Purpose of the Study:

• To evaluate the utility of upright integrated CPET (iCPET) in characterizing CTEPD patients.
• To define and identify ventilatory inefficiency in CTEPD.
• To accurately diagnose preload insufficiency in CTEPD patients.

Main Methods:

• Utilized upright integrated cardiopulmonary exercise testing (iCPET).
• Defined ventilatory inefficiency by the lack of reduction in the dead space to tidal volume ratio (VD/VT) with exercise.
• Assessed patients with CTEPD, particularly those without resting pulmonary hypertension.

Main Results:

• Upright iCPET can effectively characterize CTEPD patients.
• A specific definition of ventilatory inefficiency (lack of VD/VT reduction) aids in patient stratification.
• This approach helps identify patients with preload insufficiency.

Conclusions:

• Upright iCPET provides valuable diagnostic information for CTEPD patients with dyspnea.
• Defining ventilatory inefficiency through VD/VT response during exercise is key.
• Accurate identification of preload insufficiency can prevent misclassification and undiagnosed cases in CTEPD.