Mechanisms of Mitral Valve Dysfunction Following Mitral Valve Repair for Degenerative Disease
Author + information
- Jocelyn N. Spoon, MD∗∗ (jocy.huey{at}gmail.com),
- Vuyisile T. Nkomo, MD, MPH∗∗∗ (nkomo.vuyisile{at}mayo.edu),
- Rakesh M. Suri, MD, DPhil†,
- Sorin V. Pislaru, MD, PhD∗,
- Daniel B. Spoon, MD∗,
- Hector I. Michelena, MD∗,
- Maurice E. Sarano, MD∗ and
- Joseph F. Malouf, MD∗
Mitral valve repair is the treatment of choice for mitral regurgitation secondary to myxomatous degenerative valve disease given the associated low operative mortality and excellent long-term survival. Recurrent mitral valve dysfunction requiring reoperation following primary valve repair is uncommon, especially when performed by experienced surgeons at high-volume centers. The most common etiology of recurrent regurgitation after repair is progressive degeneration of the valvular apparatus, including new leaflet prolapse or flail. Less common mechanisms for repair failure can be categorized as procedural or technical failures and include annuloplasty dehiscence, leaflet suture rupture, incorrect artificial chord length, and incorrect annuloplasty position. Determining etiology of primary repair failure provides essential information regarding candidacy for re-repair, which is associated with superior outcomes over valve replacement (1). Our aim is to provide an echocardiography-based imaging guide to help evaluate patients presenting with recurrent mitral valve dysfunction following repair. We have included 8 total illustrative cases (Figures 1, 2, 3, 4, 5, and 6).
Progressive Degenerative Disease Causing New Leaflet Prolapse and Chordal Rupture
A 66-year-old man with dyspnea was diagnosed with bileaflet mitral valve prolapse and severe regurgitation. (A and B) Transesophageal echocardiogram (TEE) showed redundant leaflets with severe, posteriorly directed regurgitation. During gross inspection, elongated anterior leaflet chordae were identified as the primary pathology responsible for the regurgitation. (C and D) Successful repair was completed by insertion of 2 neochordae to the anterior leaflet and posterior annuloplasty band insertion. (E and F) Two years later, the patient had recurrent dyspnea related to a newly ruptured chord (pink arrow) to the middle scallop (P2) of the posterior leaflet (white arrow). (G) Three-dimensional TEE en-face view of the mitral valve confirmed intact prior repair and newly prolapsed P2 with ruptured chordae (asterisks). A 66-year-old man with a ruptured chord (pink arrow) and flail P2 (yellow arrow) (H and I) underwent successful triangular resection and posterior annuloplasty band insertion (J and K), but developed recurrent symptoms 9 years later from new P2 prolapse (L to N, yellow arrow). Used with permission from the Mayo Clinic. AV = aortic valve; LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.
Early and Delayed Mitral Inflow Stenosis Following Mitral Valve Repair
A 71-year-old woman underwent mitral valve repair with a complete annuloplasty ring at an outside institution for a flail posterior leaflet (yellow arrow) from a ruptured chord (pink arrow) (A and B). Over the next year, she experienced transient ischemic attacks. TEE showed large mobile thrombus (C, arrowheads) attached to the annuloplasty ring associated with high-velocity inflow (D) and gradient (E) across the mitral valve. Endocarditis was ruled out. (F–H) Repeat TEE after chronic anticoagulation demonstrated near complete resolution of thrombus, but persistent obstruction from an undersized annuloplasty ring. A 62-year-old man status post 2 previous mitral valve repairs at an outside institution developed exertional dyspnea approximately 12 years following repair. (I and J) Transthoracic echocardiogram apical 4-chamber depicted restricted leaflet motion and high-velocity mitral inflow and gradient. (K) Three-dimensional TEE en-face image of the mitral valve revealed annuloplasty ring (double arrows) and thickened leaflets with a restrictive valve orifice (arrowhead). Used with permission from the Mayo Clinic. Ao = aorta; other abbreviations as in Figure 1.
Residual Mitral Regurgitation Secondary to Incomplete Initial Repair
A 78-year-old man underwent mitral valve repair for severe symptomatic regurgitation and aortic valve replacement for severe aortic valve regurgitation. Pre-bypass mid-esophageal long-axis (A and B) and trans-gastric short-axis (C) views of the mitral valve suggested a flail leaflet (pink arrow) at the posteromedial commissure and associated regurgitant jet. Gross surgical inspection of the valve revealed a flail A3 segment but otherwise normal-appearing valve. The repair involved chordae resection and artificial chord placement in addition to posterior annuloplasty band insertion. Post-bypass TEE mid-esophageal (D and E) and transgastric (F and G) short-axis views revealed persistent prolapse (arrowhead) with residual commissural regurgitation initially noted to be mild but progressed to at least moderate with continued imaging. No repeat surgical intervention was performed given the difficult initial exposure of the mitral valve and presence of aortic valve prosthesis. Follow-up transthoracic echocardiogram 3 years later confirmed progression to moderate–severe mitral regurgitation. Used with permission from the Mayo Clinic. AL = anterior leaflet; PL = posterior leaflet; other abbreviations as in Figures 1 and 2.
Incorrect Neochord Length
A 63-year-old asymptomatic man with a history of mitral valve prolapse status post–mitral valve repair at an outside institution was found to have recurrent severe mitral regurgitation on routine follow-up imaging prompting reoperation. (A and B) TEE mid-esophageal 4-chamber view showed a redundant artificial chord (pink arrow) attached to a prolapsed anterior leaflet segment (yellow arrow) with severe posteriorly directed regurgitation. TEE transgastric short axis at the level of the mitral valve (C) and with the probe pulled back to the level of the gastroesophageal junction (D) revealed the site where the artificial chord had been attached (pink arrow) to the prolapsed A2/A3 segment (yellow arrow). (E) Intraoperative photograph of the anterior leaflet of the mitral valve depicted the redundancy in the previously placed artificial chord, which had not been sized correctly and thus did not appropriately support the prolapsed segment and resulted in regurgitation. Used with permission from the Mayo Clinic. Abbreviations as in Figures 1 and 3.
Displacement of Annuloplasty Ring in Addition to Clip and Leaflet Suture Dehiscence
A 63-year-old woman underwent a minimally invasive mitral repair involving leaflet resection and sutureless annuloplasty ring placement secured with nitinol clips at an outside institution. Significant mitral regurgitation recurred 4 months later necessitating reoperation. (A) Intraoperative pre-bypass TEE revealed 2 mitral regurgitant jets; (B and C) a regurgitant jet outside the annuloplasty ring posteriorly (pink arrows), consistent with annuloplasty dehiscence found to be secondary to nitinol clip detachment, and another leaflet-related jet can be seen adjacent to the site of dehiscence. (D) Three-dimensional TEE en-face view of the mitral valve showed the native valve annulus remained intact despite the localized area of annuloplasty dehiscence (arrowheads). (E) Intraoperative photograph depicting gross site of nitinol clip failure (arrowheads). (F) Intraoperative photograph of the posterior leaflet showing the site of leaflet suture dehiscence (arrows). Dehiscence is also a risk for red blood cell damage and may present as hemolysis (2). Used with permission from the Mayo Clinic. Abbreviations as in Figure 1.
Extreme Dehiscence of Complete Annuloplasty Ring
A 65-year-old man with a history of severe mitral regurgitation status post–mitral valve repair 1 year ago at an outside institution presented seeking a second opinion after being told he had recurrent regurgitation. (A) TEE mid-esophageal view revealed extensive dehiscence of his complete annuloplasty ring into the left atrium, approximately 2 cm above the plane of the mitral annulus. (B) TEE mid-esophageal view with color Doppler (baseline shifted) identified 2 regurgitant jets originating below the ring at the level of the native annulus as a result of primary leaflet pathology. (C) Three-dimensional TEE image shows how the detached ring (arrows) did not interfere with leaflet function given the superior location of the ring relative to the plane of leaflet coaptation. (D) Three-dimensional TEE with color flow demonstrated the origin and trajectory of the 2 jets of mitral regurgitation, with the larger jet directed at the detached ring (arrows). Used with permission from the Mayo Clinic. AR = annuloplasty ring; LAA = left atrial appendage; MV = mitral valve; other abbreviations as in Figure 1.
Determination of the mechanism of mitral valve dysfunction following mitral valve repair is paramount and can be done reliably with echocardiography. Two-dimensional and 3-dimensional transesophageal echocardiography should be performed in all cases of recurrent mitral valve dysfunction because of superior spatial resolution and anatomic detail when compared with transthoracic echocardiography.
Acknowledgments
The authors thank Mark A. Zangs for his time and expertise in image construction, as well as Dr. William D. Edwards for his expert review.
Footnotes
Dr. Suri has received research funding from Sorin, Abbott, Edwards Lifesciences, and St. Jude Medical; is a member of the board of Abbott (COAPT Trial Clinical Steering Committee) and St. Jude Medical (Portico Trial Steering Committee); and is a consultant for Sorin (Perceval trial national principal investigator) and Abbott (COAPT trial co-principal investigator). All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
