Prosthesis-patient mismatch after mitral valve replacement: a single-centered retrospective analysis in East China

Case Report: Using Medtronic AP360 mechanical prosthesis in mitral valve replacement for patients with mitral insufficiency after primum atrial septal defect repair to reduce left ventricular outflow tract obstruction risk

Background

Atrial septal defect is one of the most common congenital heart diseases in adults. Primum atrial septal defect (PASD) accounts for 4%-5% of congenital heart defects. Patients with PASD frequently suffer mitral insufficiency (MI), and thus, mitral valvuloplasty (MVP) or mitral valve replacement (MVR) is often required at the time of PASD repair. Unfortunately, recurrent unrepairable severe mitral regurgitation can develop in many patients undergoing PASD repair plus MVP in either short- or long-term after the repair surgery, requiring a re-do MVR. In those patients, the risk of left ventricular outflow tract obstruction (LVOTO) has increased.

Case presentation

We present five such cases, ranging in age from 24 to 47 years, who had a PASD repair plus MVP or MVR for 14-40 years while suffering moderate to severe mitral regurgitation. Using Medtronic AP360 mechanical mitral prostheses, only one patient experienced mild LVOTO.

Conclusions

The use of Medtronic AP360 mechanical mitral prostheses to perform MVR in patients with MI who had a history of PASD repair can potentially reduce the risk of LVOTO. Long-term follow-up is required to further confirm this clinical benefit associated with AP360 implantation in patients with PASD.

Impact of prosthesis-patient mismatch on late outcomes after bioprosthetic mitral valve replacement for mitral regurgitation

Negative impact of prosthesis-patient mismatch on long-term survival after valve replacement has been reported. However, the effect of prosthesis-patient mismatch after bioprosthetic mitral valve replacement has not yet been well examined. The purpose of this study was to investigate the effect of prosthesis-patient mismatch on late outcomes after bioprosthetic mitral valve replacement for mitral regurgitation. A total of 181 patients underwent bioprosthetic mitral valve replacement between April 2008 and December 2016. After excluding patients with mitral stenosis and those with incomplete data, 128 patients were included in the study. Postoperative transthoracic echocardiography was performed before discharge for all patients and the effective orifice area of bioprosthetic mitral valve was calculated using the formula: 220/pressure half-time, and the effective orifice area index was calculated by the formula: effective orifice area/body surface area. Prosthesis-patient mismatch was defined as a postoperative effective orifice area index ≤ 1.2 cm²/m². The characteristics and outcomes were compared between the groups. There were 34 patients (26.6%) with prosthesis-patient mismatch and 94 patients (73.4%) without prosthesis-patient mismatch. There were no significant differences in the in-hospital mortality and morbidities. Multivariable analysis showed that prosthesis-patient mismatch was an independent predictor of late mortality (hazard ratio 3.38; 95% confidence interval 1.69-6.75; p = 0.001) and death from heart failure (hazard ratio 31.03, 95% confidence interval 4.49-214.40, p < 0.001). Prosthesis-patient mismatch at discharge after mitral valve replacement for mitral regurgitation was associated with long-term mortality and death from heart failure.

Hemodynamic and clinical performance of the 25-mm Medtronic Mosaic porcine bioprosthesis in the mitral position

The 25-mm Medtronic Mosaic porcine bioprosthesis (MB25) is the smallest bioprosthesis that has been approved for use in the mitral position in Japan. Various studies have reported satisfactory hemodynamic performance and good long-term outcomes of the Medtronic Mosaic porcine bioprosthesis. However, the hemodynamic and clinical performances of the MB25 in the mitral position remain unknown. This study aimed to evaluate the hemodynamic and clinical performance of the MB25 in mitral valve replacement (MVR). Twenty patients who underwent MVR using the MB25 between February 2013 and April 2018 were studied. We evaluated the hemodynamic performance of the MB25, cardiac chamber size, cardiac function, and systolic pulmonary artery pressure (PAP) using echocardiography during follow-up. The study outcomes were major adverse cardiac events (MACEs) and all-cause mortality. Sixteen patients (80%) had a patient prosthesis mismatch defined as an index effective orifice area of ≤ 1.2 cm²/m². The left atrial dimension was significantly reduced after surgery (p = 0.0282). The mean pressure gradients (MPG) in the mitral position were 5.5 ± 1.7 mmHg at discharge and 4.2 ± 1.3 mmHg at 1 year postoperatively. The MPG in the mitral position significantly decreased during the follow-up period (p = 0.0489). Systolic PAP significantly improved postoperatively. The 1-, 3-, and 5-year survival rates were 87, 79, and 70%, respectively. No cardiac death occurred. There were no MACEs or reports of structural valve degeneration during the follow-up period. The hemodynamic and clinical performances of the MB25 in the mitral position were satisfactory as the smallest biological mitral valve. The MB25 is a reasonable option for MVR to reduce the surgical difficulty in high-risk patients with an advanced age, a small body size or MAC and when recurrent MVR or complex procedures are performed.

Prosthesis-patient mismatch after mitral valve replacement: A pooled meta-analysis of Kaplan-Meier-derived individual patient data

Objective

The hemodynamic effect and early and late survival impact of prosthesis–patient mismatch (PPM) after mitral valve replacement remains insufficiently explored.

Methods

Pubmed, Embase, Web of Science, and Cochrane Library databases were searched for English language original publications. The search yielded 791 potentially relevant studies. The final review and analysis included 19 studies compromising 11,675 patients.

Results

Prosthetic effective orifice area was calculated with the continuity equation method in 7 (37%), pressure half‐time method in 2 (10%), and partially or fully obtained from referenced values in 10 (53%) studies. Risk factors for PPM included gender (male), diabetes mellitus, chronic renal disease, and the use of bioprostheses. When pooling unadjusted data, PPM was associated with higher perioperative (odds ratio [OR]: 1.66; 95% confidence interval [CI]: 1.32–2.10; p < .001) and late mortality (hazard ratio [HR]: 1.46; 95% CI: 1.21–1.77; p < .001). Moreover, PPM was associated with higher late mortality when Cox proportional‐hazards regression (HR: 1.97; 95% CI: 1.57–2.47; p < .001) and propensity score (HR: 1.99; 95% CI: 1.34–2.95; p < .001) adjusted data were pooled. Contrarily, moderate (HR: 1.01; 95% CI: 0.84–1.22; p = .88) or severe (HR: 1.19; 95% CI: 0.89–1.58; p = .24) PPM were not related to higher late mortality when adjusted data were pooled individually. PPM was associated with higher systolic pulmonary pressures (mean difference: 7.88 mmHg; 95% CI: 4.72–11.05; p < .001) and less pulmonary hypertension regression (OR: 5.78; 95% CI: 3.33–10.05; p < .001) late after surgery.

Conclusions

Mitral valve PPM is associated with higher postoperative pulmonary artery pressure and might impair perioperative and overall survival. The relation should be further assessed in properly designed studies.

Impact of Prosthesis-Patient Mismatch After Mitral Valve Replacement: A Propensity Score Analysis

The effect of patient-prosthesis mismatch (PPM) on late outcomes after mitral valve replacement (MVR) remains unclear. We evaluated the impact of PPM after MVR on the late survival using propensity score matching analysis. From 2007 to 2018, 660 consecutive MVRs were performed. Effective orifice areas were obtained from a literature review of in vivo echocardiographic data, and mitral PPM was defined as an effective orifice area index of ≤1.2 cm²/m². Propensity score matching yielded a cohort of 126 patients with PPM and 126 patients without PPM. Mitral PPM was found in 37.8% of the patients. In the whole matched patients, there were no differences in late survival (log-rank test, P = 0.629) between 2 groups. Patients aged ≤70 years and those aged >70 years had no differences in late survival (log-rank test, P = 0.073 and 0.572). The Cox proportional hazards model for the overall survival showed that mitral PPM tended to decrease survival in patients aged ≤70 years (P = 0.084, hazard ratio [HR] 2.647, 95% CI: 0.876-7.994). Mitral PPM did not adversely affect long-term survival. There may be a tendency of adverse impact on late survival in patients aged ≤70 years. Implanting a safe size rather than larger size prosthesis in mitral position may be an appropriate option in older patients.

Clinical outcomes and hemodynamic performance of Dafodil™ aortic and mitral pericardial bioprosthesis: 1-year results from Dafodil-1 first-in-human trial

BACKGROUND

Bioprosthesis has been increasingly implanted for the treatment of transvalvular disease across the world. A new Dafodil™ pericardial bioprosthesis (Meril Life Sciences Pvt. Ltd., India) recently approved by Conformité Européenne (CE) is a tri-leaflet, stented, bovine valve. The purpose of Dafodil-1 first-in-human trial was to evaluate clinical safety and performance (including hemodynamic parameters) of the Dafodil pericardial bioprosthesis in patients who underwent aortic or mitral valve replacement.

METHODS

This prospective, multicenter clinical trial enrolled 60 patients (Aortic: 30 patients; Mitral: 30 patients) from seven sites across India. Safety endpoints were early (≤30 days) and late (> 30 days) mortality and valve-related morbidity. The performance endpoints were hemodynamic performance, improvement in NYHA functional class, and change in the quality of life using SF-12v1 health survey.

RESULTS

From July 2017 to July 2018, 60 patients underwent implantation of the Dafodil pericardial bioprosthesis. Post-operatively, NYHA functional class significantly improved in all the patients (Aortic: 90% NYHA class-I and 10% NYHA class-II; Mitral: 96.55% NYHA class-I and 3.45% NYHA class-II; P < 0.001). There was no death in aortic valve replacement patients till 12-month. In mitral valve replacement patients, early mortalities occurred in three patients, and late mortality occurred in one patient; none of these were valve-related. Freedom from all-cause mortality reported was 93.33% at 12-month. Mean aortic pressure gradient decreased from 52.71 ± 24.47 mmHg [with 0.89 ± 0.70 cm² effective orifice area (EOA)] pre-operatively to 14.49 ± 6.58 mmHg (EOA: 1.85 ± 0.27 cm²) at 12-month. Overall, the mitral mean pressure gradient and EOA were 4.41 ± 1.69 mmHg and 2.67 ± 0.48 cm², respectively, at 12-month. Significant improvement (P < 0.05) in the patients' quality of life was reported at all follow-ups.

CONCLUSIONS

The clinical safety and performance of the Dafodil pericardial bioprosthesis were favourable at 12-month. Moreover, a study with a larger patient population and longer follow-up is warranted to further assess the device.

TRIAL REGISTRATION

Dafodil-1 trial has been prospectively registered on 10/07/2017 under Clinical Trial Registry-India (http://www.ctri.nic.in). (Registration number: CTRI/2017/07/009008).

Prosthesis-Patient Mismatch Negatively Affects Outcomes after Mitral Valve Replacement: Meta-Analysis of 10,239 Patients

OBJECTIVE

This study sought to evaluate the impact of prosthesis-patient mismatch on the risk of perioperative and long-term mortality after mitral valve replacement.

METHODS

Databases were researched for studies published until December 2018. Main outcomes of interest were perioperative and 10-year mortality and echocardiographic parameters.

RESULTS

The research yielded 2,985 studies for inclusion. Of these, 16 articles were analyzed, and their data extracted. The total number of patients included was 10,239, who underwent mitral valve replacement. The incidence of prosthesis-patient mismatch after mitral valve replacement was 53.7% (5,499 with prosthesis-patient mismatch and 4,740 without prosthesis-patient mismatch). Perioperative (OR 1.519; 95%CI 1.194-1.931, P<0.001) and 10-year (OR 1.515; 95%CI 1.280-1.795, P<0.001) mortality was increased in patients with prosthesis-patient mismatch. Patients with prosthesis-patient mismatch after mitral valve replacement had higher systolic pulmonary artery pressure and transprosthethic gradient and lower indexed effective orifice area and left ventricle ejection fraction.

CONCLUSION

Prosthesis-patient mismatch increases perioperative and long-term mortality. Prosthesis-patient mismatch is also associated with pulmonary hypertension and depressed left ventricle systolic function. The findings of this study support the implementation of surgical strategies to prevent prosthesis-patient mismatch in order to decrease mortality rates.