Surgical Techniques for the Management of the ‘Hostile Mitral Annulus’

Double-layer horizontal cross sutures for intra-atrial mitral valve implantation: An effective surgical method for severe mitral annular calcification

Objective

Severe mitral annular calcification (MAC) can make prosthetic implantation extremely difficult. Although intra-atrial mitral valve prosthesis implantation without annular decalcification offers a simpler approach, it poses a potential rupture risk due to high left ventricular pressure. We developed a double-layer (DL) horizontal cross-suture technique, which ensures close proximity of the valve prosthesis to the calcified annulus and segregates the left atrial wall from the left ventricle. The aim of this study was to compare the outcomes of DL suture with conventional single-layer (SL) suture in patients with severe MAC.

Methods

This retrospective cohort study consecutively enrolled patients with severe MAC undergoing mitral valve replacement at Beijing Anzhen Hospital from May 2018 to December 2022. A detailed description of the DL suture method is described. Follow-up medical evaluations, including transthoracic echocardiography measurements, were obtained through outpatient chart reviews.

Results

The study included 10 patients in the DL suture group and 20 in the SL suture group. All patients in the DL group and all but 3 in the SL group achieved technical success. Compared with the SL group, the DL suture technique was associated with lower rates of perivalvular leakage, stroke, new-onset atrial fibrillation, reoperation, and 30-day mortality. Follow-up was complete, with 1 late mortality in the DL group due to stroke and 4 cardiovascular deaths in the SL group.

Conclusions

The DL horizontal cross-suture technique offers a more effective and safer approach for intra-atrial mitral valve implantation in severe MAC cases than the conventional SL suture method.

Surgical implantation of balloon-expandable heart valves for the treatment of mitral annular calcification

OBJECTIVES

The treatment of mitral valve disease in the presence of mitral annular calcification (MAC) is associated with an increased risk of cardiovascular and all-cause mortality. Various surgical and transcatheter techniques for the treatment of mitral disease with severe MAC have been described. However, these procedures are associated with high risk of operative morbidity and mortality. We describe our experience with open surgical implantation of a balloon-expandable valve (BEV) in patients with severe MAC as an alternative approach.

METHODS

BEV implantation was performed with direct vision through the left atrium via a median sternotomy or minimally invasive approach. The midportion of the anterior leaflet is excised, and a ventricular septal myectomy performed if there is high risk for left ventricular outflow tract obstruction. The primary outcome was technical success according to the Mitral Valve Academic Research Consortium criteria; secondary outcomes were 30-day and 1-year mortality.

RESULTS

From October 2015 through October 2020, 51 patients at 2 institutions underwent BEV-in-MAC (mean age, 73.9 ± 8.8 years; 60.8% [31/51] were female; mean Society of Thoracic Surgeons predicted risk of mortality: 6.8% ± 4.8%). Technical success was 94.1% (48/51). Thirty-day and 1-year mortality were 13.7% (7/51) and 33.3% (15/45), and for stroke 3.9% (2/51) and 4.4% (2/45), respectively.

CONCLUSIONS

Surgical implantation of a BEV in the mitral position offers a treatment option for patients with mitral valve disease complicated by severe MAC who are at increased risk for conventional surgical approaches and at risk for left ventricular outflow tract obstruction with transcatheter approaches.

Mitral annular calcification: challenges and future perspectives

Mitral annular calcification (MAC) is a chronic degenerative process that implies calcification on the mitral support structure. It usually appears as a bystander to other cardiac pathologies hindering surgical treatment and increasing morbidity and mortality. When addressing the mitral valve, many surgical strategies have been suggested in the past with no clear consensus on what to choose. Moreover, and as transcatheter therapies have gained popularity over the last few decades, transcatheter mitral valve implantation has appeared as another alternative to conventional surgery. In this review, we aim at describing an overview of MAC, highlighting current challenges and treatment options as well as new potential alternatives.

Intra-atrial Neomitral Ring Creation in the Presence of Severe Mitral Annulus Calcification

Severe mitral annulus calcifications significantly hinder surgical repair and replacement of the dysfunctional mitral valve. Herein, we present a novel surgical technique where we created an intra-atrial neomitral ring using a vascular Dacron graft in which a prosthetic valve was implanted. This approach is a simple alternative technique that can be used when anatomic prosthetic valve implantation is not feasible. Major assets of this approach are evasion of extensive debridement, implantation of an adequately sized prosthesis, and prosthetic material availability.

Open Atrial Transcatheter Mitral Valve Replacement in Patients With Mitral Annular Calcification

BACKGROUND

Mitral valve replacement in the setting of severe mitral annular calcification remains a surgical challenge. Transcatheter mitral valve replacement (TMVR) using an aortic balloon-expandable transcatheter heart valve is emerging as a potential treatment option for high surgical risk patients. Transseptal, transapical, or transatrial access is not always feasible, so an understanding of alternative implantation techniques is important.

OBJECTIVES

The authors sought to present a step-by-step description of a contemporary transatrial TMVR technique using balloon-expandable aortic transcatheter heart valves. This procedure has evolved over time to address valve migration, left ventricular outflow tract obstruction, and paravalvular leak. The authors present a refined technique that has been associated with the most reproducible outcomes.

METHODS

A step-by-step description of the TMVR technique and outcomes of 8 patients treated using this technique are described. Baseline patient clinical and echocardiographic characteristics and 30-day post-TMVR outcomes are presented.

RESULTS

Eight patients underwent transatrial TMVR at a single institution. Five had previous cardiac surgery. Mean STS score was 8%. Technical success by MVARC (Mitral Valve Academic Research Consortium) criteria was 100%. There was zero in-hospital and 30-day mortality. Procedural success by MVARC criteria at 30 days was 100%. Paravalvular leak immediately post-implant was none or trace in 6 and mild in 1.

CONCLUSIONS

The technique described is reproducible and was associated with favorable outcomes in this early experience. It represents a useful technique for the treatment of mitral valve disease in the setting of severe annular calcification. A structured and defined implantation technique is critical to investigators as this field evolves.

Impact of failed mitral valve repair on hospital outcome of redo mitral valve procedures

OBJECTIVES

The prognostic impact of failed mitral valve repair (FMR) on in-hospital outcome after redo mitral valve surgery has not been thoroughly investigated.

METHODS

Hospital outcomes after redo mitral valve surgery because of an FMR in patients from nine European centres were reported. Logistic regressions identified predictors of mortality in combined or isolated redo mitral valve operations. Hospital outcome was compared between propensity-matched cohorts with FMR and native mitral valves in the context of redo surgery and FMR versus failed prostheses.

RESULTS

A total of 246 patients with FMR yielded a 6.5% mortality rate at redo surgery. FMR per se did not impact mortality at multivariable analysis ( P = 0.64). A preoperative Global Initiative for Chronic Obstructive Lung Disease (GOLD) score ≥2 chronic obstructive lung disease (COPD) (OR 15.2, P < 0.01), left ventricular ejection fraction <30% (odds ratio (OR) 21.5, P = 0.005), major injury to cardiovascular structures at re-entry (OR 27.2, P < 0.01) or injury to patent left internal mammary artery-coronary artery bypass graft (OR 7.6, P = 0.03) predicted mortality in the whole FMR population. GOLD ≥ 2 COPD (OR 12.3, P = 0.049), age at surgery (OR 1.15 for each incremental year, P = 0.049) and cardiopulmonary bypass duration (OR 1.02, P = 0.022) predicted mortality in isolated redo mitral valve surgery for FMR. The fourth (> 68 years = 13.8% mortality) and the fifth quintiles of age (≥73.4 years = 14.8%) reported the highest mortality (OR 3.8 and 4.2 respectively, P = 0.002) in this subgroup. Propensity-matched cohorts of FMR and native mitral valves in the context of redo surgery showed no differences in terms of mortality ( P = 0.69) and major morbidity (acute myocardial infarction P = 0.31, stroke P = 0.65, acute kidney injury P  = 1.0), whereas more perioperative dialysis ( P = 0.04) and transfusions ( P = 0.02) were noted in propensity-matched failed prostheses compared to FMR.

CONCLUSIONS

A failed mitral repair does not impact hospital outcome of redo surgery. Given the role of severe left ventricular dysfunction and advanced age on hospital mortality rates, an early indication for redo surgery may improve outcome.

En bloc aortic and mitral valve replacement and left ventricular outflow tract enlargement using a combined transaortic and trans-septal atrial approach

Aortic and mitral valve replacement with division and reconstruction of the inter-valvular fibrous body has been described in clinical situations involving infective endocarditis, extensive annular calcifications and diminutive valve annuli. Herein, we describe a combined transaortic and trans-septal approach with division of the inter-valvular fibrosa for combined aortic and mitral valve replacement. The reconstruction of the inter-valvular fibrous body, atrial walls and aortic root was carried out using a 'three-patch' technique with bovine pericardium.