Echocardiographic Implication of Global Longitudinal Strain in Short-term Outcome Following Endoscopic Mitral Valve Repair for Primary Mitral Regurgitation

Background: Assessment of cardiac performance to determine optimal timing for surgical mitral valve repair (MVR) for primary mitral regurgitation (PMR) remains challenging. Traditional echocardiographic parameters such as left ventricular ejection fraction (LVEF) may be misleading due to volume overload and subclinical LV dysfunction. Therefore, we aimed to investigate predictive value of speckle-tracking-echocardiography (STE) derived LV global longitudinal strain (GLS) in such cases.

Methods: A total of 76 consecutive patients with adequate transthoracic echocardiogram (TTE) quality receiving isolated endoscopic MVR for PMR in 2021 were included for analysis. Patients were stratified to normal GLS (≤−18%, n = 35, group 1) and impaired GLS (>−18%, n = 41, group 2). Pre- and postoperative (5–8 days) TTE including STE measurements were performed and analyzed.

Results: Baseline patient characteristics and traditional TTE parameters such as effective regurgitation orifice area (EROA), left ventricular end-diastolic and end-systolic diameters (LVEDD, LVESD) were similar between groups. Mean GLS was -20.6% and -15.2% in group 1 and group 2 respectively, with no statistically significant difference in LVEF (60.8 ± 3.4% vs. 59.0 ± 4.5%, p = 0.098). NYHA functional class was similar, but group 1 showed substantially lower serum level of proBNP (274.6 ± 38.6 vs. 1187.2 ± 235.5 ng/L, p = 0.001). Postoperatively, patients in group 1 had significantly higher LVEF (51.1 ± 5.9% vs. 45.2 ± 5.9%, p < 0.001), and more patients with preserved LVEF (>50%) (68.6% vs. 17.1%, p < 0.001). Postoperative LV GLS was significantly reduced in both groups, but group 1 still demonstrated superior GLS (−15.9 ± 3.3% vs. −10.7 ± 2.9%, p < 0.001). In a subgroup analysis in patients with preoperative LVEF >60%, patients in group 1 exhibited superior LVEF compared with patients in group 2 (52.9 ± 4.5% vs. 46.6 ± 5.9%, p < 0.001), and preserved LVESD (37.2 ± 4.3 vs. 40.5 ± 6.0mm, p = 0.037) postoperatively.

Conclusion: Compared with traditional TTE parameters, LV GLS has the potential to predict short-term cardiac performance after MVR in PMR patients. Thus, STE seems to be a promising additional diagnostic tool for evaluating cardiac performance and to guide decision-making for surgical timing.

Publikationsverlauf

Artikel online veröffentlicht:
13. Februar 2024