Discussion
The current American Heart Association/American College of Cardiology Guidelines recommend mitral valve repair as the treatment of choice for degenerative MR. Both pre- and intra-operative echocardiography are critical to guiding surgical management in the operating room. Echocardiography enables evaluation of the of the entire MV apparatus including the leaflets, annulus and chordae tendineae, the severity and mechanism of regurgitation, and any additional cardiac pathology that increases surgical risk. Transthoracic echocardiography, as a low cost and minimally invasive diagnostic imaging modality, provides the data needed for clinical decision-making in most patients with chronic primary MR. When TTE images are inadequate, TEE is recommended. The severity of MR can be estimated using multiple echocardiographic parameters such as color doppler, effective regurgitant orifice area, vena contracta width, and pulmonary blood flow.
Outcomes, including postoperative morbidity/mortality and freedom from recurrent moderate/severe MR, after mitral valve repair have been demonstrated to be superior when performed by surgeons with extensive experience at high volume centers. These findings are consistent with guidelines recently published by The American College of Cardiology/ American Heart Association as well as the European Society of Cardiology9,10. The MV complexity score has demonstrated to have a direct correlation with the difficulty of surgical repair and the length of cardiopulmonary bypass time, both of which have implications for postoperative outcomes. The current analysis suggests the feasibility of using TEE-derived MV complexity scores to preoperatively stratify degenerative MV repair complexity. This correlation should permit expedient and cost-effective referral of appropriate candidates for MV repair to centers of excellence. The authors accordingly claim that TEE is a practical and useful imaging modality for stratification of MV complexity with the potential to improve mitral valve disease outcomes.