Assessment of Cardiac Performance by Global Longitudinal Strain after Aortic Valve Surgery in Severe Aortic Regurgitation

Background: In patients with severe aortic valve regurgitation (AVR), left ventricular (LV) remodeling takes place before symptoms occur and impairment of ejection fraction (EF) is detected. Early evaluation of cardiac performance is thus crucial for surgical timing. Previous studies highlighted strain analysis with speckle-tracking echocardiography (STE) as a tool for detection of early subclinical myocardial dysfunction. Therefore, the characteristic of strain before and after surgery for AVR and its clinical relevance remain to be investigated.

Method: A total of 98 patients, who underwent elective AV surgery due to AR from 2016 to 2020 with good image quality, were included. Transthoracic echocardiography including STE measurements were performed pre-, postoperatively, and at 1 year follow-up, and global longitudinal strain (GLS) was analyzed. Patients were categorized according to GLS at baseline: normal GLS group (GLS ≤ −18%, n = 42), and impaired GLS group (GLS > −18%, n = 56).

Results: Baseline patient characteristics and chamber quantification of LV were similar in both groups. NYHA functional class was similar, whereas preoperative proBNP value was significantly lower in normal GLS group (136.6 ± 36.1 vs. 775.0 ± 194.6 ng/L, p = 0.002). At baseline, mean GLS was −19.9 ± 1.6% in normal and −14.3 ± 3.1% in impaired GLS group, while the difference of EF did not differ significantly (56.8 ± 5.7 vs. 53.7 ± 8.5%, p = 0.059). Postoperative EF (p < 0.001) and GLS (p < 0.001) declined significantly (3.9 ± 0.9% vs. 3.2 ± 0.5%) compared with baseline. However, postoperative GLS was significantly higher in normal GLS group (−15.6 ± 3.4% vs. −12.0 ± 3.3%, p < 0.001). In addition, postoperative in-hospital stay was shorter in normal GLS group (6.6 ± 2.5 vs. 8.2 ± 3.5 days, p = 0.016). At 1-year follow-up, EF and GLS were significantly improved compared with postoperative (increment of EF: 8.5 ± 2.3% and 9.4 ± 1.1%, increment of GLS: 4.1 ± 1.0% and 3.6 ± 0.6%, both p < 0.001). Furthermore, EF at 1-year follow-up was similar between both groups (53.8 ± 6.8% vs. 53.1 ± 7.3%, p = 0.643), but again, GLS was superior in normal GLS group (−18.4 ± 1.8% vs. −16.4 ± 3.2%, p = 0.001).

Conclusion: Treatment of patients with severe AR in patients at the stage of preserved GLS results in an advantageous cardiac performance after AV surgery and a shorter in-hospital stay. In comparison to traditional parameters like EF, GLS seems to have a superior role in early detection of myocardial dysfunction and could become a promising decision-making tool for surgical timing in AR patients.

Publikationsverlauf

Artikel online veröffentlicht:
28. Januar 2023