Prognosis after valve replacement in patients with severe aortic stenosis and a low transvalvular pressure gradient.

Objectives: This study was conducted to determine the risks and benefits of valve replacement in patients with severe aortic stenosis and a low transvalvular pressure gradient.

Background: There is uncertainty regarding the appropriate management of adults with severe aortic stenosis and a transvalvular pressure gradient < or = 30 mm Hg. With only six such patients reported, one study suggested that these subjects have a prohibitive operative risk and little symptomatic improvement if they survive surgical treatment, whereas another showed that they can survive an operation and improve symptomatically.

Methods: In an attempt to clarify the risks and benefits of valve replacement in these patients, we reviewed the records of 18 patients (15 men and 3 women, aged 49 to 81 years) with severe aortic stenosis (valve area < or = 0.4 cm2/m2 body surface area), a mean transvalvular pressure gradient < or = 30 mm Hg and limiting symptoms (New York Heart Association functional class III or IV) who underwent valve replacement.

Results: Six patients (33%) (95% confidence interval 13% to 59%) died perioperatively, whereas 10 patients (56%) (95% confidence interval 31% to 78%) improved symptomatically to functional class I (n = 8) or II (n = 2) (p = NS in comparison with the 6 who died). No clinical or hemodynamic variable was predictive of survival or improvement in functional class.

Conclusions: Valve replacement in patients with severe aortic stenosis and a transvalvular pressure gradient < or = 30 mm Hg is accompanied by a considerable operative risk. Although there were no significant differences in this small series between the fraction of patients who died and those who exhibited improvement, we still recommend the procedure because many patients survive the operation and most of the survivors show an improved symptomatic status.