1Universitäres Herz- und Gefäßzentrum Hamburg Klinik und Poliklinik für Herz- und Gefäßchirurgie Hamburg, Deutschland; 2Universitäres Herz- und Gefäßzentrum Hamburg Klinik und Poliklinik für Kardiologie Hamburg, Deutschland; 3Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Kardiologie Hamburg, Deutschland
Objectives
Traditional echocardiographic parameters such as left ventricular ejection fraction (LVEF) may be misleading due to volume overload and subclinical LV dysfunction in patients with primary mitral regurgitation (PMR), which makes assessment of cardiac performance and optimal timing of mitral valve repair (MVR) challenging. Our objective was to explore the predictive value of speckle-tracking echocardiography (STE)-derived LV global longitudinal strain (GLS) in this scenario.
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 to 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
The implication of LV GLS, compared to traditional echocardiographic parameters, demonstrates potential in predicting short-term cardiac performance after MVR in PMR patients. Thus, STE emerges as a promising supplementary diagnostic tool and provides valuable insights to decision-making for surgical timing.