Commentary: More ado about nothing: Resect “versus” respect and left ventricular function after repair

Abstract

Central MessageThe focus of mitral valve repair should be to leave no more than mild residual mitral regurgitation. Resect and respect are equally successful techniques.See Article page XXX. The focus of mitral valve repair should be to leave no more than mild residual mitral regurgitation. Resect and respect are equally successful techniques. See Article page XXX. Recently data were published showing the equivalence of resect and respect techniques on left ventricular (LV) function in patients with degenerative mitral regurgitation.1van Wijngaarden A.L. Tomšič A. Mertens B.J.A. Fortuni F. Delgado V. Bax J.J. et al.Mitral valve repair for isolated posterior mitral valve leaflet prolapse: the effect of respect and resect techniques on left ventricular function.J Thorac Cardiovasc Surg. February 22, 2021; ([Epub ahead of print])Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar This excellent post-hoc analysis of a randomized study of 104 patients (the CAMRA Cardio-Link 2 study; Clinicaltrials.gov identifier NCT02552771) reports remarkably similar results.2Hibino M. Dhingra N.K. Verma S. Chan V. Quan A. Gregory A.J. et al.Mitral repair with leaflet preservation vs leaflet resection and ventricular reverse remodeling from a randomized trial.J Thorac Cardiovasc Surg. September 14, 2021; ([Epub ahead of print])Abstract Full Text PDF PubMed Scopus (3) Google Scholar LV remodeling begins early after repair, as documented on predischarge echocardiogram. This is especially prominent with the reduction of LV end-diastolic volume and dimension index, and this improvement continued at 12-month follow-up. LV end-systolic volume and dimension index did not change predischarge, but both had reduced by the 12-month echocardiogram. Correspondingly, LV ejection fraction dropped about 10 points early (61.1 ± 5.4% preoperative vs 51.7 ± 8.7% predischarge; P < .0001). In addition, by 12 months and tracking the improvement in LV end-systolic volume index, the ejection fraction had improved (56.4 ± 5.1%; P < .0001) but did not return to the preoperative level. This early reduction in LV ejection fraction, and only partial return to normal, has been reported before and likely reflects that we wait too long to operate on this group of patients.3Desai A. Thomas J.D. Bonow R.O. Kruse J. Andrei A.C. Cox J.L. et al.Asymptomatic degenerative mitral regurgitation repair: validating guidelines for early intervention.J Thorac Cardiovasc Surg. 2021; 161: 981-994.e5Abstract Full Text Full Text PDF PubMed Scopus (9) Google Scholar, 4Suri R.M. Schaff H.V. Dearani J.A. Sundt T.M. Daly R.C. Mullany C.J. et al.Recovery of left ventricular function after surgical correction of mitral regurgitation caused by leaflet prolapse.J Thorac Cardiovasc Surg. 2009; 137: 1071-1076Abstract Full Text Full Text PDF PubMed Scopus (88) Google Scholar, 5Enriquez-Sarano M. Suri R.M. Clavel M.A. Mantovani F. Michelena H.I. Pislaru S. et al.Is there an outcome penalty linked to guideline-based indications for valvular surgery? Early and long-term analysis of patients with organic mitral regurgitation.J Thorac Cardiovasc Surg. 2015; 150: 50-58Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar Asymptomatic, or mildly symptomatic patients, may be observed with “watchful waiting” until there are irreversible changes in LV function, which may reduce late survival.5Enriquez-Sarano M. Suri R.M. Clavel M.A. Mantovani F. Michelena H.I. Pislaru S. et al.Is there an outcome penalty linked to guideline-based indications for valvular surgery? Early and long-term analysis of patients with organic mitral regurgitation.J Thorac Cardiovasc Surg. 2015; 150: 50-58Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar Other notable findings included an early and sustained reduction in pulmonary artery pressures and left atrial volume index. There was no change in tricuspid regurgitation over time (only 4 patients had tricuspid valve annuloplasty). As noted in the previous report,1van Wijngaarden A.L. Tomšič A. Mertens B.J.A. Fortuni F. Delgado V. Bax J.J. et al.Mitral valve repair for isolated posterior mitral valve leaflet prolapse: the effect of respect and resect techniques on left ventricular function.J Thorac Cardiovasc Surg. February 22, 2021; ([Epub ahead of print])Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar,6McCarthy P.M. Commentary: much ado about nothing: resect or respect?.J Thorac Cardiovasc Surg. February 22, 2021; ([Epub ahead of print])Google Scholar there was no appreciable physiologic difference in LV function between the leaflet resection and leaflet preservation (neochords) groups. Although both studies1van Wijngaarden A.L. Tomšič A. Mertens B.J.A. Fortuni F. Delgado V. Bax J.J. et al.Mitral valve repair for isolated posterior mitral valve leaflet prolapse: the effect of respect and resect techniques on left ventricular function.J Thorac Cardiovasc Surg. February 22, 2021; ([Epub ahead of print])Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar,2Hibino M. Dhingra N.K. Verma S. Chan V. Quan A. Gregory A.J. et al.Mitral repair with leaflet preservation vs leaflet resection and ventricular reverse remodeling from a randomized trial.J Thorac Cardiovasc Surg. September 14, 2021; ([Epub ahead of print])Abstract Full Text PDF PubMed Scopus (3) Google Scholar were small, the findings are quite similar in this respect, and the previous study1van Wijngaarden A.L. Tomšič A. Mertens B.J.A. Fortuni F. Delgado V. Bax J.J. et al.Mitral valve repair for isolated posterior mitral valve leaflet prolapse: the effect of respect and resect techniques on left ventricular function.J Thorac Cardiovasc Surg. February 22, 2021; ([Epub ahead of print])Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar also included global LV strain. The take-home point of repair with either strategy should be to leave no residual mitral regurgitation more than mild. Using a technique with which you are comfortable will provide the patient with durable freedom from recurrent mitral regurgitation. Both techniques work fine. Mitral repair with leaflet preservation versus leaflet resection and ventricular reverse remodeling from a randomized trialThe Journal of Thoracic and Cardiovascular SurgeryPreviewIn the Canadian Mitral Research Alliance (CAMRA) Trial CardioLink-2 leaflet resection versus preservation techniques for posterior leaflet prolapse was investigated and no difference was shown in their effect on mean mitral gradient at peak exercise at 12 months postoperatively. The purpose of this subanalysis was to evaluate the effect of the 2 strategies on left ventricular (LV) reverse remodeling after repair. Full-Text PDF