Background:
Aortic valve replacement (AVR) is recommended (IIa) in symptomatic patients with paradoxical low-flow, low-gradient aortic stenosis (PLF-LG AS). This entity is characterized by pronounced LV concentric remodeling with impaired LV filling and reduced LV longitudinal systolic function and stroke volume despite preserved LV ejection fraction (p-EF). However, there is lack of data about the evolution of LV geometry and function following AVR in these patients.
Methods:
We prospectively enrolled thirty-two patients (age=71±12 years; 59% men) with PLF-LG AS (SVi<35 mL/m2, mean gradient<40 mmHg, indexed aortic valve area [AVA] 50%) who underwent AVR within 3 months following inclusion. Stroke volume was measured in the LV outflow tract by pulsed-wave Doppler and indexed for body surface area (SVi). Global left ventricular longitudinal strain (GLS) was measured by 2D speckle tracking.
Results:
Following AVR, mean gradient decreased (15±8 mmHg post vs. 30±7 pre AVR) and AVA increased significantly (1.40±0.31 vs. 0.70±0.12 cm2) (all p<0.0001). AVR was associated with a positive LV remodeling with an increase in LV end-diastolic diameter (46±4 vs. 44±4 vs mm; p=0.0027) and volume (99±21 vs. 89±20 ml, p=0.003) and a decrease in relative wall thickness (0.46±0.06 vs. 0.58±0.11; p=0.0004) and LV mass (175±37 vs. 207±44 g; p=0.002). SVi increased significantly from baseline to 1 year (36±7 vs. 31±3 ml/m2; p=0.0002), whereas LVEF remained unchanged (63±6 vs 63±7; p=NS). SVi increased significantly in the subset of patients with mild to moderate DD at baseline (all p<0.05) but not in those with severe DD (p=NS). GLS also increased significantly from baseline to 1 year (17±4 vs. 14.5±4%; p=0.03). There was a significant correlation between post-AVR increase in GLS and increase in SVi (r=0.52; p=0.02).
Conclusion:
The findings of this study demonstrate that in patients with PLF-LG AS and p-EF, AVR is associated with an increase in LV stroke volume which is mainly due to positive LV remodeling and improvement in LV longitudinal systolic function. Our results provide further support to the ACC/AHA recommendations with regard to indication of AVR in these patients.
Predictive Value of Left Ventricular Myocardial Deformation for Left Ventricular Remodeling in Patients With Classical Low-Flow, Low-Gradient Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement
