Chronic pulmonary insufficiency induced by pulmonary valve stenting in young swine significantly reduced right ventricular myocardial contractility (E max 2.6 vs 3.5 mm Hg/mL; P<0.01).
Does chronic pulmonary insufficiency alter right and left ventricular function in a young growing swine model?
In a developing swine model, chronic pulmonary insufficiency leads to adverse biventricular changes, specifically limiting biventricular functional reserve, altering RV contractility, and decreasing LV diastolic compliance.
Absolute Event Rate: 2.6% vs 3.5%
p-value: p=<0.01
Background— This study was conducted to determine the effects of chronic pulmonary insufficiency (PI) on right (RV) and left (LV) ventricular function in young growing swine. Methods and Results— Six PI and 5 control animals were studied. PI was induced by transcatheter placement of stents across the pulmonary valve. Indices of systolic function (ejection fraction, cardiac output, and cardiac functional reserve), diastolic function (compliance), and myocardial contractility (the slope of the relationship of end-systolic pressure versus end-systolic volume E max and the slope of the dP/dt max –end-diastolic volume relationship M dP/dt ) were assessed within 2 days of intervention and 3 months later. MRI was used to quantify PI and ventricular volumes. Conductance catheter techniques were used to obtain indices of contractility and diastolic compliance from pressure-volume relations at rest and under dobutamine infusion. In the PI group, pulmonary regurgitant fraction was 49.2±5.9% at 3-month follow-up. RV cardiac functional reserve was limited, diastolic function was preserved, and myocardial contractility was altered (E max =2.6±0.3 mm Hg/mL for the PI group versus 3.5±0.4 mm Hg/mL for control; P <0.01). LV cardiac functional reserve was limited, ventricular compliance decreased, and myocardial contractility was preserved. Conclusions— In the young developing heart, chronic PI alters biventricular systolic function, RV myocardial contractility, and LV diastolic performance.
Kühne et al. (Tue,) conducted a other in Pulmonary insufficiency (n=11). Transcatheter placement of stents across the pulmonary valve vs. Control was evaluated on Right ventricular myocardial contractility (E max) (p=<0.01). Chronic pulmonary insufficiency induced by pulmonary valve stenting in young swine significantly reduced right ventricular myocardial contractility (E max 2.6 vs 3.5 mm Hg/mL; P<0.01).