Does Mitral Valve Calcium in Patients Undergoing Mitral Valve Replacement Portend Worse Survival?

Contemporary experience of mitral transcatheter edge-to-edge repair technology in patients with mitral annular calcification

BACKGROUND

Mitral annular calcification (MAC) has been an exclusion for many of the earlier pivotal trials that were instrumental in gaining device approval and indications for mitral transcatheter edge-to-edge repair (M-TEER).

AIMS

To evaluate the impact of MAC on the procedural durability and success of newer generation MitraClip® systems (G3 and G4 systems).

METHODS

Data were collected from Northwell TEER registry. Patients that underwent M-TEER with third or fourth generation MitraClip device were included. Patients were divided into -MAC (none-mild) and +MAC (moderate-severe) groups. Procedural success was defined as ≤ grade 2 + mitral regurgitation (MR) postprocedure, and durability was defined as ≤ grade 2 + MR retention at 1 month and 1 year. Univariate analysis compared outcomes between groups.

RESULTS

Of 260 M-TEER patients, 160 were -MAC and 100 were +MAC. Procedural success was comparable; however, there were three patients who required conversion to cardiac surgery during the index hospitalization in the +MAC group versus none in the -MAC group (though this was not statistically significant). At 1-month follow-up, there were no significant differences in MR severity. At 1-year follow-up, +MAC had higher moderate-severe MR (22.1% vs. 7.5%; p = 0.002) and higher mean transmitral gradients (5.3 vs. 4.0 mmHg; p = 0.001) with no differences in mortality, New York Heart Association functional class or ejection fraction.

CONCLUSION

In selective patients with high burden of MAC, contemporary M-TEER is safe, and procedural success is similar to patients with none-mild MAC. However, a loss of procedural durability was seen in +MAC group at 1-year follow-up. Further studies with longer follow-ups are required to assess newer mTEER devices and their potential clinical implications in patients with a high burden of MAC.

Mitral transcatheter edge-to-edge repair: patient selection, current devices, and clinical outcomes

INTRODUCTION

Over the last two decades, mitral transcatheter edge-to-edge repair (M-TEER) has become a safe and effective therapy for severe mitral regurgitation in patients deemed at high surgical risk.

AREAS COVERED

This review aims to encompass the most relevant and updated evidence in the field of M-TEER from its inception, focusing on clinical and anatomical features for proper patient and device selection.

EXPERT OPINION

Growing operator experience and device iterations have resulted in improved clinical outcomes and an expansion of the therapy to patients with complex anatomies and clinical scenarios. Future investigations are warranted to determine the best management options and the most suitable device for every patient with MR.

Noncontrast cardiac computed tomography-derived mitral annular calcification scores in mitral valve disease

BACKGROUND AND AIMS

Mitral annular calcification (MAC) by computed tomography (CT) is reported as an independent predictor of poor outcomes. However, it currently remains unclear if quantitative MAC parameters provide more value for mitral valve disease (MVD) management, therefore, we examined the prognostic value of MAC scores using noncontrast cardiac-CT in MVD patients.

METHODS

Between January 2020 and December 2021, we prospectively enrolled 300 consecutive patients with MVD (MAC-present = 80 and MAC-absent = 220) undergoing preoperative cardiac-CT and mitral valve (MV) surgery. Noncontrast cardiac-CT images were used to qualitatively detect MAC (present or absent) and evaluate MAC scores. For analyses, we also collected baseline clinical data, intraoperative conversion (from MV repair to MV replacement), and follow-up arrhythmia data.

RESULTS

Compared with the MAC-absent group, MAC-present patients were older (62 ± 7 vs. 58 ± 9 years, p < .001), mostly women (55% vs. 39.5%, p = .017), and also had aortic valve calcification (57.5% vs. 23.2%, p < .001), mitral stenosis (82.5% vs. 61.8%, p < .001), atrial fibrillation (30% vs. 11.8%, p < .001), and larger left atrial end-diastolic dimension (LADD, 49 [44-56] versus 46 [41-50], p = .001]. Furthermore, MAC-present patients underwent more MV replacements (61.8% vs. 82.5%, p = .001) and experienced a higher intraoperative conversion prevalence (11.8% vs. 61.3%, p < .001). Multiple logistic regression analyses showed that the female gender (odds ratio [OR]/95% confidence interval [CI]/p = 2.001/1.042-3.841/0.037) and MAC scores (OR/95% CI/p = 10.153/4.434-23.253/p < .001) were independent predictors of intraoperative conversion. During a follow-up of 263 ± 134 days, MAC-present patients had more arrhythmias (42.5% vs. 9.5%, p < .001). Also, MAC-scores (hazard ratio [HR]/95% CI/p = 6.841/3.322-14.089/p < .001) and LADD (HR/95% CI/p = 1.039/1.018-1.060/p < .001) were independently associated with arrhythmias by Cox regression analyses.

CONCLUSIONS

Noncontrast cardiac CT-derived MAC-scores showed a high risk for intraoperative conversion and follow-up arrhythmias in MVD-patients.

Feasibility and Outcomes of Mitral Transcatheter Edge-To-Edge Repair in Patients With Variable Degrees of Mitral Annular Calcification

Background The clinical significance of mitral annular calcification (MAC) in patients undergoing mitral transcatheter edge-to-edge repair is not well understood. There is limited evidence regarding the feasibility, durability of repair, and the prognostic value of MAC in this population. We sought to examine the prognostic value of MAC, its severity, and its impact on procedural success and durability of mitral transcatheter edge-to-edge repair. Methods and Results We reviewed the records of 280 patients with moderate-severe or severe mitral regurgitation who underwent mitral transcatheter edge-to-edge repair with MitraClip from March 2014 to March 2022. The primary end point was cumulative survival at 1 year. Independent factors associated with the primary end point were identified using multivariable Cox regression. Among 280 patients included in the final analysis, 249 had none/mild MAC, and 31 had moderate/severe MAC. Median follow-up was 23.1 months (interquartile range: 11.1-40.4). Procedural success was comparable in the MAC and non-MAC groups (92.6% versus 91.4%, P=0.79) with similar rates of residual mitral regurgitation ≤2 at 1 year (86.7% versus 93.2%, P=0.55). Moderate/severe MAC was associated with less improvement in New York Heart Association III/IV at 30 days when compared with none/mild MAC (45.8% versus 14.3%, P=0.001). The moderate/severe MAC group had lower cumulative 1-year survival (56.8% versus 80.0%, hazard ratio [HR], 1.98 [95% CI, 1.27-3.10], P=0.002). Moderate/severe MAC and Society of Thoracic Surgeons predicted risk of mortality for mitral valve repair were independently associated with the primary end point (HR, 2.20 [1.10-4.41], P=0.02; and HR, 1.014 [1.006-1.078], P=0.02, respectively). Conclusions Mitral TEER is a safe and feasible intervention in selected patients with significant MAC and associated with similar mitral regurgitation reduction at 1 year compared with patients with none/mild MAC. Patients with moderate/severe MAC had a high 1-year mortality and less improvement in their symptoms after TEER.

Novel Multi-Parametric Mitral Annular Calcification Score Predicts Outcomes in Mitral Valve Dysfunction

The objective of the study was to construct a multi-parametric mitral annular calcification (MAC) score using computed tomography (CT) features for prediction of outcomes in patients undergoing mitral valve surgery. We constructed a multi-parametric MAC score, which ranges between 2 and 12, and consists of Agatston calcium score (1 point: <1000 Agatston units (AU); 2 points: 1000-<3000 AU; 3 points: 3000-5000 AU; 4 points: >5000 AU), quantitative MAC circumferential angle (1 point: <90°; 2 points: 90-<180°; 3 points: 180-<270°; 4 points: 270-360°), involvement of trigones (1 point: 1 trigone; 2 points: both trigones), and 1 point each for myocardial infiltration and left ventricular outflow tract extension/involvement of aorto-mitral curtain. The association between MAC score and clinical outcomes was evaluated. The study cohort consisted of 334 patients undergoing mitral valve surgery (128 mitral valve repairs, 206 mitral valve replacements) between January 2011 and September 2019, who had both non-contrast gated CT scan and evidence of MAC. The mean age was 72 ± 11 years, with 58% of subjects being female. MAC score was a statistically significant predictor of total operation time (P<0.001), cross-clamp time (P = 0.001) and in-hospital complications (P = 0.003). Additionally, MAC score was a significant predictor of time to all-cause death (P = 0.046). A novel multi-parametric score based on CT features allowed systematic assessment of MAC, and predicted clinical outcomes in patients with mitral valve dysfunction undergoing mitral valve surgery.

Management of Patients With Severe Mitral Annular Calcification: JACC State-of-the-Art Review

Mitral annular calcification (MAC) is a common and challenging pathologic condition, especially in the context of an aging society. Surgical mitral valve intervention in patients with MAC is difficult, with varying approaches to the calcified annular anatomy, and the advent of transcatheter valve interventions has provided additional treatment options. Advanced imaging provides the foundation for heart team discussions and management decisions concerning individual patients. This review focuses on the prognosis of, preoperative planning for, and management strategies for patients with MAC.

Mitral valve surgery with extensive annular calcification: review of surgical techniques and postoperative complications

Mitral annular calcification (MAC) represents an important risk factor in mitral valve (MV) surgery. Despite several procedures having been described, no surgical treatment of choice has been established so far: whether a decalcification should be systematically carried out, or if the MV should be preferentially repaired rather than replaced. A review of the literature on patients undergoing MV surgery associated with MAC was performed. Studies were excluded if dealing with endovascular procedures or emergency surgery for associated endocarditis. Case reports were also not considered in the final analysis. The literature search identified 1429 potentially eligible studies, and 25 papers were eventually included. Several surgical techniques were described to approach this challenging condition. During MV surgery, the presence of MAC favors the occurrence of suboptimal intraoperative outcomes. MAC-related complications such as atrioventricular groove rupture, cerebrovascular accident, new permanent pacemaker implantation, intraoperative conversion from valve repair to replacement and mortality were analyzed. MV surgery in the presence of MAC considerably impacts the postoperative outcomes in terms of morbidity and mortality. A great variability of surgical techniques is reported, suggesting the need for standardization of the approach.

Early outcomes of transcatheter mitral valve replacement with the Tendyne system in severe mitral annular calcification

BACKGROUND

Treatment of mitral regurgitation (MR) associated with severe mitral annular calcification (MAC) is challenging due to the high risk of fatal atrioventricular groove disruption and significant paravalvular leak.

AIMS

The aim of this study was to evaluate the outcomes of transcatheter mitral valve replacement (TMVR) with the Tendyne valve (Abbott Structural) in patients with MR and MAC.

METHODS

Twenty patients (mean age 78 years; 11 women) who were treated with the Tendyne valve, either compassionate use (CU; closed) or as part of The Feasibility Study of Tendyne in MAC (NCT03539458), had reported outcomes in a median follow-up duration of 368 days.

RESULTS

In all patients, a valve was implanted with no procedural mortality and successful hospital discharge. Two embolic events occurred, including one with mesenteric ischaemia and one non-disabling stroke. At 30 days and one year, all-cause mortality occurred in one (5%) and eight patients (40%), respectively. At one year, six patients had been hospitalised for heart failure (30%). There was no prosthetic dysfunction, and MR remained absent in all patients at one year. Clinical improvement, measured by New York Heart Association Functional Class, occurred in 11 of 12 patients who were alive at one year. Among seven survivors with Kansas City Cardiomyopathy Questionnaire (KCCQ) data, mean increase in KCCQ score was 29.9±26.3 at one year with improvement of ≥10 points in five (71.4%) patients.

CONCLUSIONS

In patients with MR and severe MAC, TMVR with the Tendyne valve was associated with encouraging acute outcomes, midterm durability, and clinical improvement. Dedicated TMVR therapy may have a future role in these anatomically challenging, high-risk patients.

Transcatheter edge-to-edge mitral valve repair in patients with mitral annulus calcification

BACKGROUND

MAC is commonly found in patients affected with MR, and it is associated with high morbidity, mortality and worse cardiac surgical outcomes. Transcatheter edge-to-edge repair could be an alternative treatment, although there is little evidence in this population.

AIMS

The aim of this study was to analyse the safety, efficacy and durability of MitraClip implantation in patients affected with mitral regurgitation (MR) and mitral annulus calcification (MAC).

METHODS

We analysed the outcomes of 61 suitable patients affected with severe MR and moderate or severe MAC (the "MAC" group) and 791 patients with no or mild MAC (the "NoMAC" group) treated with the MitraClip device.

RESULTS

Procedural success was similar (91.8% vs 95.1%, p=0.268, in MAC and NoMAC, respectively), with a very low rate of complications. At one-year follow-up, 90.6% of MAC and 79.5% of NoMAC patients had MR grade ≤2 (p=0.129), 80% in both groups remained in NYHA Functional Class ≤II, and a significant reduction in cardiac readmissions was observed (65% vs 78% in MAC vs NoMAC, p=0.145). One-year mortality tended to be higher in MAC patients (19.7% vs 11.3%, p=0.050), with no difference in cardiovascular mortality (15.3% vs 9.2%, p=0.129).

CONCLUSIONS

MitraClip use in selected patients with moderate or severe MAC is safe, feasible and achieves good clinical and echocardiographic results at one-year follow-up.

Mitral Annular Calcification in Obstructive Hypertrophic Cardiomyopathy: Prevalence and Outcomes

BACKGROUND

The prevalence and clinical impact of mitral annular calcification (MAC) in patients with obstructive hypertrophic cardiomyopathy (HCM) are largely unknown.

METHODS

We reviewed 2113 HCM patients who underwent septal myectomy from January 2000 to April 2016. Preoperative and intraoperative echocardiograms along with operative notes were reviewed to identify MAC. Survival was estimated and compared using Kaplan-Meier analysis and log-rank test. Cox regression analysis was used to identify factors independently associated with mortality.

RESULTS

MAC was identified in 390 (18.5%) patients. Older age, female sex, and presence of mitral valve leaflet calcification were strongly associated with higher odds of having MAC. Patients with MAC had higher resting LVOT gradients, more likely to have worse mitral valve regurgitation (MR) preoperatively, and more likely to undergo a concomitant mitral valve replacement (6% vs 1%, P<0.001) compared to those without MAC. Postoperatively, patients with MAC had marginally higher residual MR (13% vs 8%). After a median follow-up of 6.95 (IQR 3.7- 12.1) years, survival of patients with MAC at 1, 5 and 10 years was 99%, 92% and 69% respectively. Adjusted analysis identified MAC as an independent predictor of poor survival (HR 1.46, 95% CI 1.08 to 1.97; P=.014).

CONCLUSIONS

MAC is a frequent finding in older patients with obstructive HCM, more likely to be seen in females, and is associated with higher rates of concomitant mitral valve replacement. Despite higher prevalence of comorbidities, MAC remained an independent predictor for overall mortality following septal myectomy.

Surgical and Transcatheter Mitral Valve Replacement in Mitral Annular Calcification: A Systematic Review

Mitral annular calcification with mitral valve disease is a challenging problem that could necessitate surgical mitral valve replacement (SMVR). Transcatheter mitral valve replacement (TMVR) is emerging as a feasible alternative in high-risk patients with appropriate anatomy. PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched from inception to December 25, 2019 for studies discussing SMVR or TMVR in patients with mitral annular calcification; 27 of 1539 articles were selected for final review. TMVR was used in 15 studies. Relevant data were available on 82 patients who underwent hybrid transatrial TMVR, and 354 patients who underwent transapical or transseptal TMVR. Outcomes on SMVR were generally reported as small case series (447 patients from 11 studies); however, 1 large study recently reported outcomes in 9551 patients. Patients who underwent TMVR had a shorter median follow-up of 9 to 12 months (range, in-hospital‒19 months) compared with patients with SMVR (54 months; range, in-hospital‒120 months). Overall, those undergoing TMVR were older and had higher Society of Thoracic Surgeons risk scores. SMVR showed a wide range of early (0%-27%; median 6.3%) and long-term mortality (0%-65%; median at 1 year, 15.8%; 5 years, 38.8%, 10 years, 62.4%). The median in-hospital, 30-day, and 1-year mortality rates were 16.7%, 22.7%, and 43%, respectively, for transseptal/transapical TMVR, and 9.5%, 20.0%, and 40%, respectively, for transatrial TMVR. Mitral annular calcification is a complex disease and TMVR, with a versatile option of transatrial approach in patients with challenging anatomy, offers a promising alternative to SMVR in high-risk patients. However, further studies are needed to improve technology, patient selection, operative expertise, and long-term outcomes.

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.

Mitral Annular Calcification: Association with Atherosclerosis and Clinical Implications

PURPOSE OF REVIEW

This review summarizes the pathophysiology of mitral annular calcification (MAC) with recent findings and current strategies for diagnosis and treatment.

RECENT FINDINGS

Major factors in MAC development seem to be shear stress of the flow past the mitral valve, local inflammation, and dysregulation in regulators of mineral metabolism. MAC itself poses daunting technical challenges. Implanting a valve on top of the calcium bar might lead to paravalvular leak (PVL) that is less likely to heal. Annular decalcification allows for better valve seating and potentially better healing and less PVL. This, however, comes with the risk for catastrophic atrioventricular groove disruption. MAC can be sharply dissected with the scalpel; the annulus can be reconstructed with the autologous pericardium. Transcatheter mitral valve replacement is a promising approach in the treatment of patients who are deemed high-risk surgical candidates with severe MAC. MAC is a multifactorial disease that has some commonalities with atherosclerosis, mainly regarding lipid accumulation and calcium deposition. It is of great clinical importance, being a risk marker of cardiovascular events (including sudden death) and, with its progression, can have a negative impact on patients' lives.

Hybrid Mitral Valve Replacement: A Heart-Team Approach to Severe Mitral Annular Calcification

Mitral annular calcification tends to be significant in patients of advanced age or with underlying processes such as increased mechanical stress. When severe, it can significantly affect perioperative outcomes, especially if mitral decalcification is required for success. This report describes a versatile heart-team approach to a very complex condition. (Level of Difficulty: Advanced.).

Clinical outcomes of mitral valve intervention in patients with mitral annular calcification: A systematic review and meta-analysis

BACKGROUND

Mitral valve (MV) disease with mitral annular calcification (MAC) poses a surgical challenge and the clinical outcomes of MV surgery as well as transcatheter mitral valve replacement (TMVR) remain relatively unexplored. We performed a systematic review and meta-analysis to assess the effects of MAC on clinical outcomes following MV surgery and TMVR.

METHODS

We searched MEDLINE and EMBASE databases until February 2019 for studies comparing clinical outcomes of MV surgery or TMVR in patients with and without MAC. Data were extracted by two independent investigators. Outcomes were perioperative and midterm complications and mortality.

RESULTS

Seven observational studies enrolling 2902 patients were included. MAC patients were older, more likely to be female with greater chronic lung disease and kidney failure. Perioperative mortality was similar between patients with and without MAC undergoing MV surgery (risk ratio [RR], 1.15; 95% confidence interval [CI], 0.50-2.65; P = .74). MAC was associated with a higher risk of bleeding, permanent pacemaker implantation, and periprosthetic leak. Midterm mortality was greater in MAC patients undergoing MV surgery (incident rate ratio [IRR], 1.32; 95% CI, 1.05-1.67; P = .02). MAC patients undergoing TMVR had higher perioperative (RR, 4.65; 95% CI, 2.93-7.38; P < .01) and 1-year (RR, 5.44; 95% CI, 3.49-8.49; P < .01) mortality, decreased procedural success, greater left ventricular outflow tract obstruction and need for conversion to surgery when compared with patients undergoing TMVR for dysfunction of a bioprosthetic valve or annuloplasty ring.

CONCLUSION

MV procedures in patients with MAC are associated with higher mortality and morbidity. This is largely driven by the high-risk patient profile associated with MAC. TMVR holds promise but has important limitations and should be reserved for select patients.