Hemodynamic and biomechanical impact of proximal aortic surgery on the cardiovascular system: a systematic review and meta-analysis

Background: The consequences of proximal aortic (PA) replacement with a stiff vascular prosthesis remain insufficiently understood. This systematic review and meta-analysis aims to consolidate evidence regarding the hemodynamic and biomechanical effects of PA surgery on the cardiovascular system.

Methods: Four databases were searched on April 16th, 2025. Clinical and experimental studies reporting hemodynamic or biomechanical outcomes after PA compliance alterations were included. Exclusion criteria comprised non-original work, computational models, acute procedures, interventions beyond the PA, and PA constriction surgeries. Primary outcomes reflected cardiac functioning, hemodynamics, and aortic biomechanics.

Results: Thirteen studies (six clinical, seven experimental) were included. Six studies measured changes pre- and post-intervention, seven studies compared changes to a control group. Pulse pressure (investigated in four studies) significantly increased in one experimental study (37.7±5.9 vs. 49.2±6.9 mmHg, P=0.01). Left ventricular mass (one study) increased significantly following stiff prosthetic replacement versus optimal medical therapy (3.67±4.1 vs. 0.62 ±4.4 g/m², P<0.001). Blood flow velocity of the PA (two studies) showed significant increases in both studies. Two (of five) studies reported significant increases in aortic wall mechanics parameters including mean wall shear stress (WSS) (0.31 vs. 0.82 Pa, P=0.04) and maximal WSS (0.55 vs. 1.11 Pa, P=0.04). Meta-analysis (four studies) found increased distensibility [standardized mean change score (SMCC) 0.50, 95% confidence interval (CI): 0.24–0.76, k=3] and circumferential strain (SMCC 0.55, 95% CI: 0.00–1.10), k=3) of the descending aorta. Ejection fraction (SMCC 0.08, 95% CI: −0.29–0.45), k=3) and pulse pressure (SMCC 0.47, 95% CI: −0.36–1.31), k=3) remained unchanged. Evidence of certainty was low, and risk of bias was moderate.

Conclusions: PA stiffening due to a vascular prosthesis appears to have limited systemic hemodynamic effects, likely due to compensatory mechanisms (e.g. increased left ventricular mass and distal aortic adaptation). Local distensibility, WSS and flow dynamics are adversely affected.