Safety and utility of dobutamine and pressure wire use in the hemodynamic assessment of low-flow, low-gradient aortic stenosis with reduced left ventricular ejection fraction

Abstract

Background: The ACC/AHA guidelines recommend low-dose dobutamine challenge for hemodynamic assessment of the severity of AS in patients with low flow, low gradient aortic stenosis with reduced ejection fraction (EF) (LFLG-AS; stage D2). Inherent pitfalls of echocardiography could result in inaccurate aortic valve areas (AVA), which have downstream prognostic implications. Data on the safety and efficacy of coronary pressure wire and fluid-filled catheter use for low dose dobutamine infusion is sparse.

Methods: We retrospectively analyzed 39 consecutive patients with EF<50%, AVA<1cm² and SVI<35ml/m² on echocardiography who underwent simultaneous right and left heart catheterization. Hemodynamic assessments were performed at baseline and at every increment in the dobutamine infusion rate (The infusion was continued until maximal dose of dobutamine or a mean AV gradient>40mmHg was attained. The occurrence of sustained ventricular arrhythmias, symptomatic hypotension or intolerable symptoms leading to cessation of infusion was recorded. Transient ischemic attacks (TIAs) or clinically apparent strokes periprocedurally or up to 30days after the procedure were recorded.

Results: Dobutamine challenge confirmed true AS in 26 patients (67%) and pseudosevere AS in 34%. No sustained arrhythmias, hypotension or cessation of infusion from intolerable symptoms were observed. No clinical strokes or TIAs were observed up to 30days after procedure in any of these patients.

Conclusions: Hemodynamic assessment of AS using a pressure wire with dobutamine challenge is a safe and effective tool in identifying truly severe AS in patients with LFLG-AS with reduced EF.

Keywords: Dobutamine; Low flow low gradient aortic stenosis; Pressure wire.