Swan ganz catheter

RHC was predominantly performed via the right internal jugular vein, using a Swan Ganz catheter (Baxter Health Care Corp). If patients had >1 RHC prior to HT, the one closest to HT or assist implantation was analyzed. Mean pulmonary artery pressure (MPAP), pulmonary artery wedge pressure (PAWP), mean right atrial pressure (MRAP), and mean arterial pressure were recorded during RHC. Heart rate was recorded from ECG. CO was measured by thermodilution. Cardiac index, stroke volume (SV), SV index, left ventricular stroke work index (LVSWI), right ventricular stroke work index (RVSWI), transpulmonary gradient (TPG), pulmonary vascular resistance (PVR), PVR index, and total PVR (TPVR) were calculated using the following formulas: cardiac index=CO/body surface area; SV=CO/heart rate; SV index=SV/body surface area; LVSWI=(mean arterial pressure−PAWP)×SV index; RVSWI=(MPAP−MRAP)×SV index; TPG=MPAP−PAWP; PVR=TPG/CO; PVR index=TPG/cardiac index; and TPVR=MPAP/CO.

Right heart catheterization (RHC) was predominantly performed through the right internal jugular vein using a Swan Ganz catheter (Baxter Health Care Corp). If patients had more than one RHC before HTx, the one closest to the HTx or a ventricular assist device implantation as a bridge‐to‐heart HTx was used. Pulmonary artery pressure (mPAP, PAP_diastolic, and PAP_systolic), pulmonary artery wedge pressure (PAWP), mean right atrial pressure (mRAP), and mean arterial pressure (MAP) were measured. HR was recorded from electrocardiogram. CO was measured by the thermodilution technique at the pulmonary artery position, and an average was calculated using at least three injections. The following formulas were used to calculate cardiac index (CI) = CO/body surface area; stroke volume index = CI/HR × 1000; right ventricular stroke work index = stroke volume index × (mPAP‐mRAP) × 0.0136; transpulmonary gradient (TPG) = MPAP‐PAWP; pulmonary vascular resistance (PVR) = TPG/CO; diastolic pressure gradient (DPG) = PAP_diastolic − PAWP; and pulmonary artery pulsatility index (PAPi) = (PAP_systolic − PAP_diastolic)/mRAP.

The patients with PAH were diagnosed by experienced cardiologists and defined at time of analysis in accordance with clinical practice and prevailing ESC/ERS PH guidelines, as a resting mPAP ≥ 25 mmHg, at a pulmonary arterial wedge pressure ≤ 15 mmHg and a PVR ≥ 3 Wood units, as assessed by RHC.^{3 (link),4 (link)} RHCs were performed in the supine position at rest, predominantly via the right internal jugular vein, using a Swan–Ganz catheter (Baxter Health Care Corp., Santa Ana, CA, USA). Cardiac output was measured by thermodilution. Echocardiography and/or magnetic resonance tomography, spirometry with diffusion capacity and high-resolution computed tomography, and pulmonary scintigraphy were performed to exclude Groups II, III, and IV PH.

RHC

right-sided heart catheterization

was performed by certified interventionists with a balloon-tipped, flow-directed Swan-Ganz catheter (Baxter Healthcare, Irvine, Calif) to derive cardiac output, cardiac index, mean pulmonary artery pressure, pulmonary capillary wedge pressure, and pulmonary vascular resistance. Six-minute walk distance was measured according to American Thoracic Society guidelines (11 (link)).

RHCs were performed as a part of the routine clinical investigation for all patients, using a Swan–Ganz catheter (Baxter Health Care, Santa Ana, CA, USA), inserted predominantly via an introducer in the right internal jugular vein, at The Hemodynamic Lab, The Section for Heart Failure and Valvular Disease, Skåne University Hospital (Lund, Sweden). Haemodynamic parameters including mPAP, mean right atrial pressure (mRAP), pulmonary arterial wedge pressure (PAWP), diastolic pulmonary arterial pressure, systolic pulmonary arterial pressure and mean arterial pressure (mAP) were measured during the procedure. Cardiac output (CO) was estimated using thermodilution.
Cardiac index (CI), pulmonary vascular resistance (PVR), left ventricular stroke work index (LVSWI) and right ventricular stroke work index (RVSWI) were calculated using the following formulae: CI=CO/body surface area (BSA), PVR=(mPAP−PAWP)/CO, LVSWI=(mAP−PAWP)×stroke volume (SV)/BSA and RVSWI=(mPAP−mRAP)×SV/BSA.