Alterations in transesophageal pulsed Doppler indexes of filling of the left ventricle after pericardiotomy

The impact of pericardial constraint on patterns of left ventricular filling was measured by transesophageal pulsed Doppler echocardiography in 30 patients undergoing elective nonvalvular cardiac surgery. Peak early left ventricular filling velocity increased from 0.52 ± 0.11 to 0.56 ± 0.15 m/s (p < 0.05) and early left ventricular filling fraction increased from 60 ± 9% to 65 ± 9% (p < 0.005) after pericardiotomy. The study group was retrospectively subdivided into two groups based on the prepericardiotomy mean right atrial pressure, an index of intrapericardial pressure and hence pericardial constraint. In 13 patients with a mean right atrial pressure <6 mm Hg, no significant changes in early left ventricular filling were evident after pericardiotomy. In 17 patients with a mean right atrial pressure ≥6 mm Hg indicative of a greater degree of pericardial constraint before pericardiotomy, significant increases in peak early filling velocity (0.52 ± 0.13 to 0.57 ± 0.19 m/s, p < 0.05), peak early filling rate (4.29 ± 0.67 to 4.66 ± 0.86 stroke volume/s, p < 0.05) and early left ventricular filling fraction (57 ± 7% to 63 ± 8%, p < 0.001) were measured after pericardiotomy. Thus, the pericardium does constrain early left ventricular filling and its effects are more pronounced in patients with an elevated right atrial pressure.