Inhaled Nitric Oxide and Inhaled Prostacyclin After Cardiac Surgery for Heart Transplant or LVAD Placement

Combined Inhaled Nitric Oxide and Inhaled Prostacyclin After Cardiac Surgery for Heart Transplantation and for Left Ventricular Assist Device Placement

Research study evaluating the individual and combined effects of inhaled nitric oxide (iNO) and inhaled prostacyclin (iPGI2), on the function of the right heart after surgery for either heart transplant or for left ventricular assist device (LVAD) placement. The investigators hope to learn if these two medications, when given together after surgery, improve right heart function by lowering blood vessel pressures in the lungs. The investigators hope to learn if the combined effects of these two medications are better than either medication used alone. Participants were selected as a possible participant in this study because right heart problems are common during and after surgery for heart transplant and for LVAD placement. In addition, iNO is always given during and after these two types of surgeries at Stanford to help improve how the right heart functions.

The study will begin once the participant arrives in the cardiothoracic intensive care unit (CTICU) after heart surgery for either heart transplant or LVAD placement. As is standard of care after these types of surgeries, the participant will arrive in the CTICU with a breathing tube already in place, receiving iNO, and connected to a breathing machine. The participant will be receiving relaxing medication in an intravenous line provided by the cardiac anesthesiologist and the CTICU physicians. The participant will be unaware of the study period while the participant is sedated. Data will be collected from the monitor screen connected to the participant's arterial and venous lines, and if placed, LVAD monitor. These data are:

Central venous pressure (CVP) Mean arterial pressure (MAP) Mean pulmonary artery pressure (MPAP) Cardiac Index (CI) Systemic vascular resistance (SVR) Pulmonary vascular resistance (PVR) Right ventricular stroke work index (RVSWI) LVAD Flow LVAD Pulsatility Index (PI)

These data will be collected at five different time periods during the first eight hours after surgery.

1. Time zero. Data will be collected after surgery upon your arrival to the CTICU while receiving iNO.
2. After two hours of iNO treatment data will be collected. iPGI2 will then be combined with the current iNO.
3. After two hours of combined iNO and iPGI2 treatment, data will be collected. iNO will then be stopped.
4. After two hours of iPGI2 treatment data will be collected. iNO will be restarted.
5. After two hours of combined iNO and iPGI2 treatment, data will be collected. The study ends after this data collection time.

Inclusion Criteria:

• Adult cardiac surgical patients scheduled to undergo either heart transplantation or LVAD placement

Exclusion Criteria:

• Patients with prior documented allergic reactions or intolerance to either nitric oxide or prostacyclin will be excluded. Patients not undergoing heart transplantation or LVAD placement will be excluded.