Left Ventricular Mechanics Differ in Subtypes of Aortic Stenosis Following Transcatheter Aortic Valve Replacement

Abstract

BackgroundLeft ventricular (LV) mechanics are impaired in patients with severe aortic stenosis (AS). We hypothesized that there would be differences in myocardial mechanics, measured by global longitudinal strain (GLS) recovery in patients with four subtypes of severe AS after transcatheter aortic valve replacement (TAVR), stratified based upon flow and gradient.MethodsWe retrospectively evaluated 204 patients with severe AS who underwent TAVR and were followed post-TAVR at our institution for clinical outcomes. Speckle-tracking transthoracic echocardiography was performed pre- and post-TAVR. Patients were classified as: (1) normal-flow and high-gradient, (2) normal-flow and high-gradient with reduced LV ejection fraction (LVEF), (3) classical low-flow and low-gradient, or (4) paradoxical low-flow and low-gradient.ResultsBoth GLS (−13.9 ± 4.3 to −14.8 ± 4.3, P < 0.0001) and LVEF (55 ± 15 to 57 ± 14%, P = 0.0001) improved immediately post-TAVR. Patients with low-flow AS had similar improvements in LVEF (+2.6 ± 9%) and aortic valve mean gradient (−23.95 ± 8.34 mmHg) as patients with normal-flow AS. GLS was significantly improved in patients with normal-flow (−0.93 ± 3.10, P = 0.0004) compared to low-flow AS. Across all types of AS, improvement in GLS was associated with a survival benefit, with GLS recovery in alive patients (mean GLS improvement of −1.07 ± 3.10, P < 0.0001).ConclusionsLV mechanics are abnormal in all patients with subtypes of severe AS and improve immediately post-TAVR. Recovery of GLS was associated with a survival benefit. Patients with both types of low-flow AS showed significantly improved, but still impaired, GLS post-TAVR, suggesting underlying myopathy that does not correct post-TAVR.

Prognostic value of ventricular longitudinal strain in patients undergoing transcatheter aortic valve replacement: A systematic review and meta-analysis

“…But the current results were controversial. Some studies revealed a significant prognostic value of LVLS ( 17 , 28 ) and concluded baseline LVLS was associated with poor survival ( 11 , 23 ), but others also found it not associated with a survival benefit ( 15 , 16 , 18 , 22 ). This meta-analysis found that the impaired pooled LVLS was associated with an increased risk for combined ACM and MACE.…”

Left Ventricular Systolic Dysfunction in Aortic Stenosis: Pathophysiology, Diagnosis, Management, and Future Directions

“… 27 In low-flow low-gradient (LFLG) AS patients, GLS improved but did not normalize, suggesting a degree of irreversible adverse remodeling and myocardial damage. 26 , 28 In LFLG AS, GLS was a stronger predictor of LV recovery after TAVR than LVEF. 22 …”

“…27 In low-flow low-gradient (LFLG) AS patients, GLS improved but did not normalize, suggesting a degree of irreversible adverse remodeling and myocardial damage. 26,28 In LFLG AS, GLS was a stronger predictor of LV recovery after TAVR than LVEF. 22 Additionally, the role of LV mass index (LVMi) regression in LVEF recovery has been highlighted among patients in the PARTNER I, II, and S3 trials and registries.…”