Functional mitral stenosis following mitral valve repair

The Predictors and Outcomes of Functional Mitral Stenosis following Surgical Mitral Valve Repair: A Retrospective Analysis

To optimize mitral valve repair outcomes, it is crucial to comprehend the predictors of functional mitral valve stenosis (FMS), to enhance preoperative assessments, and to adapt intraoperative treatment strategies. This study aimed to identify FMS risk factors, contributing valuable insights for refining surgical techniques. Among 228 selected patients, 215 underwent postoperative echocardiography follow-ups, and 36 met the FMS criteria based on a mean trans-mitral pressure gradient of >5 mmHg. Patients with FMS exhibited higher pulmonary systolic arterial pressure and increased late mortality during the follow-up. Univariable logistic regression analysis identified several risk factors for FMS, including end-stage renal disease, anterior leaflet lesion, concomitant aortic valve replacement, smaller ring size, ring type, and neochordae implantation. Conversely, resection alone and resection combined with neochordae implantation had protective effects against FMS. Multivariable logistic regression analysis revealed that smaller ring sizes and patch repair independently predicted FMS. When focusing on degenerative mitral regurgitation, the neochordae implantation without resection in leaflet repair, emerged as an independent predictor of FMS. Surgeons should weigh the substantial impact of surgical procedures on postoperative trans-mitral pressure gradients, emphasizing preoperative evaluation and techniques such as precise ring size assessment and effective leaflet management.

The impact of annuloplasty ring or band implantation on post-repair mitral valve haemodynamic performance

OBJECTIVES

The clinical importance of optimal post-repair mitral valve diastolic performance is increasingly being recognized. The haemodynamic effect of a partial annuloplasty band implantation, in comparison to a full ring, remains insufficiently explored.

METHODS

Patients undergoing mitral valve repair for pure degenerative disease between 2011 and 2019 at 2 experienced heart valve centres were eligible for inclusion. Exclusion criteria were concomitant procedures other than tricuspid valve repair and ablation procedures for atrial fibrillation. Pre-discharge and follow-up echocardiograms (1-4 years after surgery) were analysed to assess haemodynamic mitral valve performance.

RESULTS

Of 535 patients meeting the inclusion criteria, 364 (68.0%) patients underwent full annuloplasty ring and 171 (31.0%) partial band implantation. On predischarge echocardiogram, post-repair mitral valve gradient and area did not differ between groups [2.89 mmHg (IQR 2.26-3.72) vs 2.60 mmHg (IQR 1.91-3.55), P = 0.19 and 1.98 cm2 (IQR 1.66-2.46) vs 2.03 cm2 (IQR 1.55-3.06), P = 0.15]. However, multivariable linear regression analysis demonstrated band annuloplasty as a determinant of larger valve area (coefficient 0.467 cm2, standard error 0.105, P < 0.001). On multivariable analysis, no significant impact on post-repair gradient was observed (-0.370 mmHg, standard error 0.167, P = 0.36). At follow-up, the differences between groups disappeared and multivariable regression analysis failed to demonstrate a significant impact of annuloplasty device type on mitral valve gradient (coefficient -0.095 mmHg, standard error 0.171, P = 1.00) or area (coefficient -0.085 cm2, standard error 0.120, P = 1.00). These results were confirmed with a linear mixed model analysis.

CONCLUSIONS

Partial band annuloplasty was related to an improved haemodynamic profile directly after valve repair for degenerative disease but the effect was short-lived. Our results suggest that the type of annuloplasty device has no durable impact on diastolic valve performance.

Computational Modeling of the Subject-Specific Effects of Annuloplasty Ring Sizing on the Mitral Valve to Repair Functional Mitral Regurgitation

Surgical repair of functional mitral regurgitation (FMR) that occurs in nearly 60% of heart failure (HF) patients is currently performed with undersizing mitral annuloplasty (UMA), which lacks short- and long-term durability. Heterogeneity in valve geometry makes tailoring this repair to each patient challenging, and predictive models that can help with planning this surgery are lacking. In this study, we present a 3D echo-derived computational model, to enable subject-specific, pre-surgical planning of the repair. Three computational models of the mitral valve were created from 3D echo data obtained in three pigs with HF and FMR. An annuloplasty ring model in seven sizes was created, each ring was deployed, and post-repair valve closure was simulated. The results indicate that large annuloplasty rings (> 32 mm) were not effective in eliminating regurgitant gaps nor in restoring leaflet coaptation or reducing leaflet stresses and chordal tension. Smaller rings (≤ 32 mm) restored better systolic valve closure in all investigated cases,but excessive valve tethering and restricted motion of the leaflets were still present. This computational study demonstrates that for effective correction of FMR, the extent of annular reduction differs between subjects, and overly reducing the annulus has deleterious effects on the valve.

Risk Factors for Postrepair Elevated Mitral Gradient: A Post-hoc Analysis of a Randomized Trial

BACKGROUND

Predischarge elevated mean mitral gradients (>5 mm Hg) may occur after repair for degenerative mitral regurgitation. We sought to identify risk factors associated with elevated gradients and to evaluate its impact on functional outcomes at 12 months in this subanalysis of the Canadian Mitral Research Alliance CardioLink-2 trial.

METHODS

One hundred four patients with degenerative mitral regurgitation undergoing mitral repair were randomized to either a leaflet resection or preservation strategy. Logistic regression was used to identify risk factors associated with an elevated gradient. Functional outcomes at 12 months were compared between participants with and without elevated gradients.

RESULTS

Elevated gradients was identified in 15 participants (14.4%), which was not significantly different based on allocation to each repair strategy (P = .10). Patients with elevated gradients were more likely to be women (odds ratio [OR], 4.28; 95% confidence interval [CI], 1.29-14.19; P = .02) and to have a lower preoperative hemoglobin level (OR, 0.93; 95% CI, 0.89-0.98; P = .01) and smaller intercommissural diameter (OR, 0.86; 95% CI, 0.76-0.97; P = .02) and mitral annuloplasty size (OR, 0.71; 95% CI, 0.57-0.87; P = .001). The ratio of intercommissural diameter-to-annuloplasty size was similar between those with and without elevated gradients (both 0.8 ± 0.1, P = .69). At 12 months those with elevated gradients had a worse New York Heart Association functional status (P = .0001), lower peak oxygen saturation in exercise test (P = .01), smaller body weight-walk distance product (P = .02), and higher Borg scale (P = .01) in the 6-minute walk test.

CONCLUSIONS

Female gender, smaller mitral anatomy sizes, and lower preoperative hemoglobin levels were associated with postoperative elevated mitral gradients, which was in turn were associated with reduced functional status. Further research is warranted to investigate these potential risk factors.

Mitral stenosis in a teenager after rheumatic mitral valve regurgitation valve repair: A case report

Introduction

Mitral stenosis (MS) is a widely known complication of mitral valve repair for non-rheumatic mitral regurgitation (MR). Few reports are available on the occurrence of MS after mitral valve repair for rheumatic MR in young populations.

Case summary

A 14-year-old girl presented with orthopnea, abdominal distension, and bilateral lower-limb edema. She was cachectic, with a high-pitched holosystolic murmur best heard at the cardiac apex, bilateral basal crackles, tender hepatomegaly, pitting pedal edema, and jugular venous distension. Antistreptolysin O (ASO) titer was elevated. Transthoracic echocardiography (TTE) revealed the loss of central coaptation of the mitral valve with leaflet restriction and MR, annular dilatation of the tricuspid valve, and tricuspid regurgitation (TR). She had AHA/ACC stage D mitral and TR s. Tricuspid annuloplasty and mitral valve repair for rheumatic MR were performed using Carpentier Edwards numbers 30 and 34, respectively. Following surgery, the weight and body mass index (BMI) rapidly normalized. The patient also developed progressive MS.

Discussion

Previous studies in adults have described the etiopathogenesis of MS after non-rheumatic mitral valve repair. There is a paucity of reports describing the development of MS over the span of months after rheumatic MR valve repair in early pubescent children.

Conclusion

Growth spurts during puberty can potentially affect MR repair, as the mitral valve prosthesis based on the preoperative Body Surface Area (BSA) is outgrown. There is a need for research on planning, prognostication, and development of an optimal, individualized, and adaptable approach to MR intervention in early pubescence.

Left atrial strain and clinical outcome in patients with significant mitral regurgitation after surgical mitral valve repair

Background

This study aimed to investigate the prognostic value of left atrial (LA) strain in patients with significant mitral regurgitation (MR) after surgical mitral valve (MV) repair.

Methods

A total of 169 patients (age 55 ± 15 years, 88 men) with moderate or severe MR on echocardiogram at least 6 months after surgical MV repair for primary MR were studied. Two-dimensional, Doppler, and speckle tracking echocardiography including MR quantitative measures, chamber size, and LA strain were comprehensively analyzed. The primary outcome was a composite of cardiovascular death, heart failure hospitalization, and MV reoperation.

Results

During a median of 44.4 months [interquartile range (IQR): 18.7-70.3 months] of follow-up, 44 patients (26%) experienced clinical events; these patients had greater MR volume, elevated mean diastolic pressure gradient and pulmonary artery systolic pressure, and enlarged chamber size compared with patients who did not experience events. Patients with events showed significantly lower LA strain [13.3% (IQR: 9.3-23.8%) vs. 24.0% (IQR: 13.1-31.4%), p = 0.003] and higher MR volume/LA strain [3.09 ml/% (IQR: 2.06-5.80 ml/%) vs. 1.57 ml/% (IQR: 1.04-2.72 ml/%), p < 0.001] than those without events. MR volume/LA strain was a good predictor of clinical outcomes (cut-off 1.57 ml/%, area under the curve 0.754, p < 0.001). On multivariable Cox proportional analysis, MR volume/LA strain was independently associated with clinical outcomes (hazard ratio: 1.269, 95% confidence interval: 1.109-1.452, p < 0.001) along with pulmonary artery systolic pressure.

Conclusion

A measure of LA mechanical function relative to MR volume is associated with clinical outcomes in patients with significant MR after surgical MV repair.

Assessment of patients with a suspected cardioembolic ischemic stroke. A national consensus statement

OBJECTIVES

Several cardiovascular, structural, and functional abnormalities have been considered as potential causes of cardioembolic ischemic strokes. Beyond atrial fibrillation, other sources of embolism clearly exist and may warrant urgent action, but they are only a minor part of the many stroke mechanisms and strokes that seem to be of embolic origin remain without a determined source. The associations between stroke and findings like atrial fibrillation, valve calcification, or heart failure are confounded by co-existing risk factors for atherosclerosis and vascular disease. In addition, a patent foramen ovale which is a common abnormality in the general population is mostly an innocent bystander in patients with ischemic stroke. For these reasons, experts from the national Danish societies of cardiology, neurology, stroke, and neuroradiology sought to develop a consensus document to provide national recommendations on how to manage patients with a suspected cardioembolic stroke. Design: Comprehensive literature search and analyses were done by a panel of experts and presented at a consensus meeting. Evidence supporting each subject was vetted by open discussion and statements were adjusted thereafter. Results: The most common sources of embolic stroke were identified, and the statement provides advise on how neurologist can identify cases that need referral, and what is expected by the cardiologist. Conclusions: A primary neurological and neuroradiological assessment is mandatory and neurovascular specialists should manage the initiation of secondary prophylactic treatment. If a cardioembolic stroke is suspected, a dedicated cardiologist experienced in the management of cardioembolism should provide a tailored clinical and echocardiographic assessment.