Overcoming a Surgical Challenge: Inverted Aortic Prosthetic Valves in Small Mitral Annulus

Abstract

We have read with great interest the paper by Barac and colleagues [1Barac Y.D. Zwischenberger B. Schroder J.N. et al.Using a regent aortic valve in a small annulus mitral position is a viable option.Ann Thorac Surg. 2018; 105: 1200-1204Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar] concerning the use of mechanical aortic prostheses in small mitral annulus. Many different and effective techniques can be used for aortic annulus enlargement. Moreover, new sutureless and stentless valves have proven to leave low gradients even in small sizes [2Ghoneim A. Bouhout I. Demers P. et al.Management of small aortic annulus in the era of sutureless valves: a comparative study among different biological options.J Thorac Cardiovasc Surg. 2016; 152: 1019-1028Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar]. Nevertheless, heavily calcified mitral valves can be a challenge [3Salhiyyah K. Kattach H. Ashoub A. et al.Mitral valve replacement in severely calcified mitral valve annulus: a 10-year experience.Eur J Cardiothorac Surg. 2017; 52: 440-444Crossref PubMed Scopus (15) Google Scholar]. Besides, an extensive debridement of the fibrous tissue surrounding the mitral valve can lead to an atrioventricular disruption, with fatal consequences. Therefore, implanting an inverted aortic valve may be a possible solution to overcome this complicated surgical scenario of a heavily calcified mitral valve with a small annulus, when a small mitral prosthesis is not available. We have also analyzed our experience in this matter. We have implanted 22 inverted aortic prostheses in mitral position from 2010 to 2017. Of these patients, 63.64% had predominantly mitral stenosis. Mean body surface area was 1.67 m2. Six patients had a previous mitral valve surgery. The most frequently implanted valve size was an inverted ATS 22-mm aortic valve (ATS Medical, Minneapolis, MN). All the implanted prostheses were mechanical prostheses. Two patients died during their postoperative hospitalization. During a 27-month mean follow-up, periodic transthoracic echocardiograms were performed, obtaining a median transvalvular gradient of 5.8 mm Hg (interquartile range: 4.65 to 7.65 mm Hg). Effective orifice area could not be calculated from the data given in the reports, but considering severe transvalvular stenosis as mean gradients greater than 10 mm Hg, 2 patients had this complication, closely related to their body surface area (2.05 m2 and 2.14 m2). Four patients (20%) died during the follow-up, 3 of them of congestive heart failure. We are deeply concerned with the fact that this is not an ideal solution. However, in spite of the lack of effective orifice area measurements during the follow-up, our results, comparable to the ones published in The Annals [1Barac Y.D. Zwischenberger B. Schroder J.N. et al.Using a regent aortic valve in a small annulus mitral position is a viable option.Ann Thorac Surg. 2018; 105: 1200-1204Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar], prove that this technique can be used as a bailout life-saving alternative in small mitral annulus. Using a Regent Aortic Valve in a Small Annulus Mitral Position Is a Viable OptionThe Annals of Thoracic SurgeryVol. 105Issue 4PreviewOutcome of mitral valve replacement in extreme scenarios of small mitral annulus with the use of the Regent mechanical aortic valve is not well documented. Full-Text PDF ReplyThe Annals of Thoracic SurgeryVol. 106Issue 2PreviewWe were extremely happy to read the letter of Redondo and colleagues [1] and hear about a similar experience as ours [2]. Small mitral annulus is a life-threatening condition in the operating room and one that has very few solutions. We agree that this solution [2] is not perfect and will need further long-term experiences. However, no solution is going to be perfect in these difficult patients, and readers should look at each patient closely in choosing an option. Full-Text PDF