Page 170 - Assessing right ventricular function and the pulmonary circulation in pulmonary hypertension Onno Anthonius Spruijt

10
Methods
Subjects
We prospectively included precapillary PH patients (idiopathic pulmonary arterial hypertension (IPAH), hereditary pulmonary arterial hypertension (HPAH) and chronic thromboembolic pulmonary hypertension (CTEPH)) and no-PH controls who performed an invasive cardiopulmonary exercise test (iCPET) in the VU University Medical Center from January 2013 until July 2014. Subjects with a history of left sided heart failure, valvular heart disease, arrhythmias or neuromuscular disease preventing the subject to exercise, were excluded.
In total, 24 subjects performed an iCPET test, including 17 PH patients (13 IPAH, 1 HPAH and 3 CTEPH patients) and 7 no-PH control subjects. The control group consisted of subjects in whom the iCPET did not confirm a previous suspicion of PH. In 9 IPAH patients, the iCPET was part of an ongoing clinical trial that was approved by the Medical Ethical Review Committee of the VU University Medical Center (Registration number: NL41878.029.13). In the remaining 15 subjects, the iCPET was part of their clinical evaluation. All subjects gave written informed consent for usage of the data for research purposes.
Maximal cardiopulmonary exercise test (CPET)
The day prior to the invasive exercise test, a maximal CPET was performed in the upright position using an electromagnetically braked cycle-ergometer (Ergoline GmbH, Bitz, Germany) according to the ATS guidelines [18]. Breath-by-breath measurements were made of oxygen consumption (VO2), carbon dioxide output (VCO2) and ventilation (VE) (Vmax229, Sensormedica, Yorba Linda, CA, USA).
Invasive cardiopulmonary exercise test (iCPET)
A balloon-tipped, flow directed 7,5 Fr, triple-lumen Swan-Ganz catheter (Edwards Lifesciences LLC, Irvine, CA) was inserted in the pulmonary artery via the jugular vein under local anesthesia and constant ECG monitoring. The ports of the catheter were placed in the right atrium, right ventricle and pulmonary artery. The zero reference level for the pressure transducer was placed at mid- thoracic level in supine position. Subsequently, a second catheter was placed in the radial artery under local anesthesia. After placement of the pulmonary artery and radial artery catheters, patients were positioned on a recumbent bicycle (Lode, Groningen, The Netherlands) in supine position. After calibration of the equipment, resting hemodynamics (right atrial pressure, right ventricular pressure, pulmonary artery pressure and systemic blood pressure) were continuously