Contemporary Surgical and Transcatheter Management of Mitral Annular Calcification

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.

Clinical Outcomes of Mitral Valve Disease With Mitral Annular Calcification

The prevalence of mitral valve disease with mitral annular calcification (MAC) and its clinical outcomes remain uncertain. This study sought to evaluate the prevalence of significant mitral disease due to MAC, and the impact of intervention on the clinical outcomes in these patients. All patients who underwent transthoracic echocardiography (TTE) between January 2014 and December 2015 in our health care system were reviewed and identified for having MAC with significant mitral valve disease (i.e., either≥moderate mitral regurgitation (MR) or mitral stenosis (MS)). The primary endpoints of the study were all-cause mortality and a composite outcome of mortality or heart failure hospitalization at 3-year follow-up. Of 41,136 patients who underwent TTE, MAC was identified in 2,855 (6.9%) patients, including 434 (1.1% of total) patients who had significant MR and/or MS (median age [IQR], 80 [73 to 87] years; 63% women). MAC predominately involved the posterior annulus (95%), with the majority having calcification of both trigones (55%), the leaflets (71%), and circumferential involvement (67%). During 3-year follow-up, 59 (14%) patients underwent surgical or transcatheter MV intervention. Patients who did not undergo mitral intervention had higher all-cause mortality (HR 2.80, 95% CI 1.60 to 4.92; p <0.001) and a greater risk of the composite outcome (HR 1.43, 1.00 to 2.04; p = 0.05) than those treated. Survival at 3-year follow-up was markedly greater in those with mitral intervention (78% vs 50%; p <0.001). This survival benefit remained after multivariable adjustment. In conclusion, MAC affects approximately % of patients who undergo echocardiography. Those with significant mitral valve disease due to any degree of MAC have poor survival, which may be ameliorated with transcatheter or surgical intervention.

Ultrasonic Emulsification of Severe Mitral Annular Calcification During Mitral Valve Replacement

PURPOSE

Severe mitral annular calcification (MAC) increases surgical complexity and is independently associated with increased operative mortality for mitral valve replacement (MVR). Recently we adopted ultrasonic emulsification/aspiration for annular decalcification to address these risks and describe our early experience with this new technology.

DESCRIPTION

Excluding previous mitral valve surgery or endocarditis, 179 patients with MAC underwent MVR at a single institution between January 2015 and March 2020. Of these, 15 consecutive patients with severe MAC (≥50% of the annulus) underwent annular decalcification with ultrasonic emulsification/aspiration as an adjunct treatment during MVR from April 2019 to March 2020.

EVALUATION

Mean patient age was 68 ± 12 years, and 72% (n = 128) were female. Mean preoperative left ventricular ejection fraction was 60% ± 11%, and mean mitral valve gradient was 9.1 ± 4.4 mm Hg. Concomitant procedures included antiarrhythmia (n = 52), aortic valve replacement (n = 32), and coronary artery bypass grafting (n = 20). There were no operative deaths or strokes in the group undergoing ultrasonic emulsification and aspiration.

CONCLUSIONS

The use of ultrasonic emulsification and aspiration in severe MAC patients may help mitigate the risks of MVR and facilitate operative success in this challenging, high-risk population.

How to Manage Mitral Stenosis Due to Mitral Annular Calcification

PURPOSE OF REVIEW

Mitral annular calcification (MAC) is associated with cardiovascular comorbidities and events and in the presence of mitral stenosis (MS) represents a high-risk cohort with limited treatment options. Emerging hybrid, minimally invasive, and transcatheter therapies that use circumferential MAC as an anchor for mitral valve replacement are emerging, but none are consistently associated with ideal outcomes.

RECENT FINDINGS

In patients with MAC and nonrheumatic calcific mitral stenosis who are severely symptomatic, mitral intervention may be indicated. Surgical decalcification and replacement of the mitral valve remains the conventional therapy. Surgical techniques to avoid decalcification are being described including a left atrium to left ventricular apex graft conduit. Transcatheter balloon-expandable valves designed for the aortic valve have been implanted in the mitral position in MAC with a surgical direct transatrial transcatheter approach or transseptal transcatheter approach. Left ventricular outflow tract (LVOT) obstruction remains prevalent and associated with increased mortality. Direct transatrial approach allows for surgical resection of the anterior leaflet to mitigate this risk, and percutaneous therapies to lacerate the anterior leaflet or to ablate the basal septum are being developed. Cardiac computed tomography has emerged as a requisite for patient selection and procedural planning and has powerful predictive value for LVOT obstruction and valve embolization in valve-in-MAC. Novel transcatheter valves designed specifically for the mitral space are being studied in patients with MAC. MAC with mitral stenosis remains a challenging disease. Advances in technique, technology, and imaging may create new and reproducible treatment options with low procedural mortality for this challenging disease entity.