Immediate hemodynamic effects of transcatheter aortic valve replacement on left ventricular stroke volume and carotid artery blood flow

Abstract

Introduction: Transcatheter aortic valve replacement (TAVR) is performed in selected patients with severe aortic valve stenosis, leading to immediate relief of left ventricular outflow obstruction. The purpose of this study was to evaluate the immediate hemodynamic effects of TAVR on left ventricular stroke volume (SVLVOT) and common carotid artery stroke volume (SVCCA). Material and methods: Twenty-five TAVR patients were included in this prospective observational study. Patients were treated under either local, or general anesthesia. Echocardiographic, and carotid ultrasound measurements were performed in the operating room pre (T1), and post (T2) TAVR. Changes in SVLVOT, SVCCA, carotid peak systolic velocity (PSV), pulsatility index (PI) and other carotid Doppler parameters were evaluated. Results: Following TAVR, the aortic valve area (AVA) increased from 0.8 [0.6–0.9] to 1.9 [1.6–2.3] cm2 (p < 0.001), and the peak transvalvular gradient (PGAV) decreased from 70 [65–81] to 15 [11-18] mm Hg (p < 0.001) from T1 to T2. SVLVOT increased from 58 ± 17 to 69 ± 24 ml, p < 0.01, whereas SVCCA remained unchanged (from 10 [7-11] to 10 [8-11] ml, p = 0.50). Δ SVLVOT was 19 [7–31] % and Δ SVCCA was 1 [-7-20] %, p < 0.05. PSV increased from 68 ± 17 to 81 ± 17 cm/s, p < 0.001, and PI increased from 1.7 [1.5–2.2] to 2.2 [1.7–2.6], p < 0.001. Conclusion: Successful TAVR resulted in immediate improvement of left ventricular stroke volume, whereas carotid stroke volume remained unchanged.

Keywords

• Common carotid artery
• Carotid blood flow
• Transcatheter aortic valve replacement
• Stroke volume
• Carotid Doppler ultrasound1