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

Pushing the hybrid approach to the edges, three stories in one: a case report

Background

Mitral annular calcification (MAC) is common in the elderly. Extensive calcification has been historically challenging for the cardiac surgeons, with traditional surgical approaches carrying significant risks. Less invasive approaches have recently been explored in an attempt to reduce this risk.

Case summary

We report the case of a 75-year-old woman who presented with recurrent pulmonary oedema, due to severe MAC and mitral regurgitation. Her past medical history included bioprosthetic aortic valve replacement 5 years ago. Given the extensive MAC and the patient's frailty, a minimally invasive hybrid approach with direct implantation of a transcatheter balloon expandable Sapien 3 valve was selected to manage her. Although the post-surgical result was initially excellent with elimination of the mitral regurgitation, the patient's post-operative course was marked by two serious complications, namely, acute severe aortic regurgitation, due to rupture of the bioprosthetic valve's right cusp, and severe paravalvular leak of the Sapien valve, due to posterior migration towards the left atrium. These were managed successfully with emergency valve-in-valve implantation using the 'double chimney' technique for the bioprosthetic aortic valve, as well as transeptal valve-in-valve implantation of a 2nd Sapien valve in the mitral valve, which sealed the gap between the 1st Sapien and the calcified mitral annulus.

Discussion

This case illustrates a less invasive approach for the management of severe MAC. Complications can still occur in this high-risk group of patients, and therefore, such cases should be managed with close collaboration between cardiac surgeons and cardiologists, in centres with high expertise.

Echocardiographic Profiling Predicts Clinical Outcomes After Mitral Transcatheter Edge-to-Edge Repair

BACKGROUND

Prior studies investigating the impact of residual mitral regurgitation (MR), tricuspid regurgitation (TR), and elevated predischarge transmitral mean pressure gradient (TMPG) on outcomes after mitral transcatheter edge-to-edge repair (TEER) have assessed each parameter in isolation. We sought to examine the prognostic value of combining predischarge MR, TR, and TMPG to study long-term outcomes after TEER.

METHODS AND RESULTS

We reviewed the records of 291 patients who underwent successful mitral TEER at our institution between March 2014 and June 2022. Using well-established outcomes-related cutoffs for predischarge MR (≥moderate), TR (≥moderate), and TMPG (≥5 mm Hg), 3 echo profiles were developed based on the number of risk factors present (optimal: 0 risk factors, mixed: 1 risk factor, poor: ≥2 risk factors). Discrimination of the profiles for predicting the primary composite end point of all-cause mortality and heart failure hospitalization at 2 years was examined using Cox regression. Overall, mean age was 76.7±10.6 years, 43.3% were women, and 53% had primary MR. Two-year event-free survival was 61%. Predischarge TR≥moderate, MR≥moderate, and TMPG≥5 mm Hg were risk factors associated with the primary end point. Compared with the optimal profile, there was an incremental risk in 2-year event-rate with each worsening profile (optimal as reference; mixed profile: hazard ratio (HR), 2.87 [95% CI, 1.71-5.17], P<0.001; poor profile: HR, 3.76 [95% CI, 1.84-6.53], P<0.001). Echocardiographic profile was statistically associated with the 2-year mortality end point (optimal as reference; mixed profile: HR, 3.55 [95% CI, 1.81-5.96], P<0.001; poor profile: HR, 3.39 [95% CI, 2.56-7.33], P=0.02).

CONCLUSIONS

The echocardiographic profile integrating predischarge TR, MR, and TMPG presents a novel prognostic stratification tool for patients undergoing mitral TEER.

Mitral Annular Calcification-Related Valvular Disease: A Challenging Entity

Mitral valve annular calcification-related valvular disease is increasingly common due to the rising prevalence of age-related mitral annular calcifications. Mitral annular calcification alters the structure and function of the mitral valve annulus, which in turn causes mitral valve regurgitation, stenosis, or both. As it frequently coexists with comorbid conditions and overlapping symptoms, mitral annular calcification-related valvular disease poses significant diagnostic and therapeutic challenges. For instance, left ventricular diastolic dysfunction hinders the assessment of mitral valvular disease. Detection of mitral annular calcifications and assessment of related mitral valve disease hinge on two-dimensional echocardiography. Comprehensive assessment of mitral annular calcifications and related mitral valve disease may require multidetector computed tomography and three-dimensional echocardiography. Invasive hemodynamic testing with exercise helps identify the cause of symptoms in patients with comorbid conditions, and transcatheter interventions have emerged as a viable therapeutic option for older patients. After an outline of the normal mitral annulus, we examine how mitral annular calcifications lead to mitral valve disease and how to accurately assess mitral regurgitation and stenosis. Lastly, we review surgical and transcatheter approaches to the management of mitral annular calcification-related mitral valve regurgitation, stenosis, or both.