Background: In patients with chronic severe mitral regurgitation, the preoperative systolic function may be preserved as a consequence of the loading conditions imposed by the regurgitant lesion, which increases the left ventricular ejection fraction (LVEF). Left Ventricular Strain Imaging provides an alternative to LVEF in the detection of subclinical systolic dysfunction early on before deterioration of LVEF sets in. This study aimed to predict if GLS and GCS could predict short term outcomes in patients with chronic severe mitral regurgitation who underwent mitral valve repair or replacement.
Method: Patients with Chronic Severe Mitral Regurgitation (MR) who underwent mitral valve surgery in Philippine Heart Center from 2016 to 2017 were identified. Patients with coronary artery disease, aortic stenosis, moderate to severe aortic regurgitation and shunt anomalies, LVEF <30%, and patients with poor echo window were excluded from the study. The variables included are GLS and GCS, and short-term postoperative outcomes like mortality, prolonged intubation, arrhythmia, LV failure, and prolonged ICU stay and need of inotropic support.
Results: 42 subjects were included in the study. 14 patients were included in the first group (with adverse clinical events) and 28 patients in the second group (without adverse clinical events). In the group with adverse clinical events, the RVFAC is significantly lower and higher pulmonary artery pressure (RVFAC 41 ± 7.4% vs. 47 ± 7.6%, p value 0.02; PAP 59.5 ± 20.7 mmHg vs. 46.1 ± 20.5 mmHg, p value 0.05). GLS is a sensitive test in predicting outcomes of mitral valve surgery (sensitivity 100%, negative predictive value 100%). GCS is neither a sensitive nor a specific test to predict outcomes of corrective surgery for mitral regurgitation (sensitivity 21%, specificity 46%).
Conclusion: The GLS score of patients in both groups were both abnormal and lower GLS in the group with adverse clinical events (-15.65 ± 3.46 vs. -15.84 ± 4.43, p value 0.89). The GCS in the group with adverse events is higher than in the group with no reported adverse clinical events (-21.1 ± 5.22% vs. -19.86 ± 5.81%, p value 0.51). GLS is a sensitive test to predict adverse clinical events after mitral valve surgery for Chronic Severe Mitral Regurgitation. The cut-off value is - 19.86%. GCS is not a good predictor of outcome after mitral valve surgery. The cut-off value is - 18.38%.