Serial left ventricular performance evaluated by cardiac catheterization before, immediately after and at 6 months after balloon aortic valvuloplasty

Abstract

Although impaired ventricular function has been shown to improve after aortic valve replacement, there are few data on hemodynamic changes after balloon aortic valvuloplasty based on follow-up catheterization. Of 71 patients surviving 6 months after balloon aortic valvuloplasty, 41 agreed to late recatheterization. All patients had pre- and postvalvuloplasty and 6 month catheterization data measured with high fidelity micromanometer pressure recordings and simultaneous digital subtraction left ventriculography.The hemodynamic result immediately after valvuloplasty included a reduction in the aortic valve gradient and a moderate increase in aortic valve area (0.51 ± 0.14 to 0.81 ± 0.19 cm2, p < 0.0001). Ejection fraction increased slightly (52 ± 18 to 55 ± 17%, p < 0.0001) despite a decrease in peak positive rate of rise of left ventricular pressure (dP/dt 1,650 ± 460 to 1,500 ± 490 mm Hg/s, p < 0.05). There was also a decrease in left ventricular afterload and a small decrease in preload.At 6 month recatheterization, the mean aortic valve gradient and area were similar to baseline values, with 31 (76%) of 41 patients demonstrating valvular restenosis. At 6 months many left ventricular hemodynamic variables, including peak positive dP/dt and stroke work, also resembled prevalvuloplasty values. However, left ventricular end-diastolic volume was reduced (111 ± 40 ml at 6 months versus 136 ± 52 ml before valvuloplasty, p < 0.01). The mean left ventricular ejection fraction was unchanged from prevalvuloplasty values in the study group of 41 patients, but was significantly improved in 9 of 15 patients with a baseline ejection fraction <50%.Thus, recatheterization at 6 months demonstrates left ventricular remodeling and a modest improvement in ventricular performance, with the left ventricle being less dilated while maintaining stroke work and cardiac output. These changes occur despite a high incidence of valve restenosis, indicating that balloon aortic valvuloplasty should be reserved for patients unable to tolerate surgical valve replacement.