The Effects of Pericardiotomy on Diastolic Reserve in Humans

This study will enroll patients with risk factors for LV diastolic dysfunction, either coronary artery disease or aortic stenosis, who are already undergoing cardiac surgery for clinical purposes (e.g. coronary artery bypass grafting or valvular heart disease).

Hemodynamic tests will be performed using standard clinical resources used as part of routine care in this setting, including pulmonary artery (PA) catheterization. After obtaining written informed consent, patients will undergo induction with general anesthesia as per clinical practice. The chest will be open but pericardium left intact. Cardiac hemodynamics (PA wedge pressure, PAWP; PA pressure, PAP, right atrial pressure, RAP) will be measured using PA catheter already in place at rest, and then during conditions of increased cardiac preload, induced by passive leg elevation and saline bolus (300 ml administered over 1-2 minutes).

The surgical team will then perform anterior pericardiotomy, with removal of pericardial restraint similar to our percutaneous approach but using currently-available surgical tools. This will not be a complete pericardiectomy but rather a limited anterior incision to gain access to the heart for surgical exposure (standard care).

The surgical team will then repeat hemodynamic assessments at rest and with acute volume loading (leg raise + saline) in exactly the same manner as with the pericardium intact. Our hypothesis is that as compared to pericardium intact, the increase in PAWP with volume loading will be reduced following opening of the pericardium.