| dc.description.abstract | Background: Uncertainty remains about the timing for intervention in primary MR. The incremental and clinical value of newer techniques including LV and LA deformation, 3D LV volumes, myocardial work and cardiac biomarkers are poorly understood. We aimed to examine whether advanced echocardiographic imaging techniques, exercise tests and blood biomarkers may be able to identify the earliest signs of LV dysfunction, predict post-operative outcomes and objectively detect symptoms in patients with primary MR which may help guide the timing of intervention. Method: In the asymptomatic cohort, resting and exercise echocardiography combined with CPET were performed prospectively in 97 asymptomatic patients with moderate to severe or severe primary MR. In the surgery cohort, echocardiography was performed at baseline and one year after MV surgery in 98 patients with severe degenerative MR. Results: In the asymptomatic cohort, 54% of patients had reduced exercise capacity, i.e. VO2 peak < 84% of the predicted value. 18% of patients stopped the exercise test because of dyspnoea. Higher rest PASP was a predictor of dyspnoea during exercise testing. LV end-diastolic volume was a better predictor of the subsequent mitral surgery. In the surgery cohort, after mitral surgery, 6 (6%) patients died, and LV dysfunction developed in 12 (12%) patients, i.e. LVEF <50%. Reservoir LA strain and global work index were associated with post-operative LVEF. However, pre-operative GLS and NT-proBNP were independent predictors of post- operative LVEF. LA strain parameters and NT-proBNP were associated with the presence of symptoms However, GWI and PASP were independently associated with the occurrence of symptoms. Conclusion: This thesis demonstrated that presence of adverse features markers such as impaired myocardial deformation, reduced myocardial work index, pulmonary hypertension and high NT-proBNP was associated with poor prognosis. These markers are non-invasive, safe and relatively easy to obtain. The combination of CPET and exercise echocardiography provides unique data in the assessment of symptomatic status and it should be used much more frequently in the assessment of MR and perhaps even incorporated as standard part of clinical practice. | en_US |
