Mitral Valve Replacement With a Third-Generation Porcine Valve: An Italian Multicentered Study

Long-Term Outcomes of Bioprosthetic Valves in the Mitral Position: A Pooled Meta-Analysis of Reconstructed Time-to-Event Individual Patient Data

Bioprosthetic mitral valve replacement (bMVR) use is increasing; however, data regarding long-term durability are lacking. We sought to perform a reconstructed individual patient data meta-analysis from published Kaplan-Meier curves to ascertain survival, freedom from valve degeneration, and reoperation in studies published since 2010. We explored the effects of age and valve type (bovine pericardial or porcine valve) on outcomes. We searched MEDLINE, OVID, Embase, and Cochrane CENTRAL for studies reporting at least 3 years of follow-up after bMVR and published since 2010. The Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) tool was used to assess methodologic quality. Kaplan-Meier curves were digitized to extract individual patient data and reconstructed estimates for overall survival, freedom from structural valve deterioration (SVD), and freedom from reoperation. A total of 20 studies (16,465 patients) were included. A total of 9 studies reported on porcine valves, 6 reported on bovine, and 7 did not specify the valve type. The overall survival after bMVR at 15 years was 40% (confidence interval 38% to 42%), freedom from reoperation at 15 years was 79% (confidence interval 76% to 82%), and freedom from SVD at 15 years was 64% (58% to 70%). Freedom from SVD was improved in the 70+ years age group (93% up to 25 years, hazard ratio 6.6 [2.5 to 17] for 18 to 59 vs >70 years, p <0.0001). There was no difference in valve durability or survival between bovine pericardial or porcine valves. In this meta-analysis of patients who underwent bMVR using newer generation valves, the inverse relation between age and SVD was reiterated in the 70+ years age group. The prosthesis type made no difference in the outcomes.

Long-term outcomes of bioprosthetic valves in the mitral position a systematic review of studies published over the last 20 years

OBJECTIVES

Although the use of bioprostheses for mitral valve replacement (bMVR) is on the rise, their long-term durability is not well described. Defining bMVR durability will be instrumental in setting the standard against which the performance of transcatheter mitral replacement is to be judged against. The authors of this systematic review aimed to identify, assess the quality and review the outcomes in studies reporting on long-term outcomes after bMVR published over the last 20 years.

METHODS

Medline, Embase and Cochrane CENTRAL were searched for studies that have reported outcomes beyond a minimum of 5 years of follow-up after bMVR. Cohort characteristics, definitions of structural valve deterioration (SVD) and outcomes were summarized. The risk of bias in included studies was assessed using the Cochrane QUIPS tool.

RESULTS

Twenty-one studies, including 15 833 patients, were identified. Sixty-four percent of all implants were porcine and the remaining bovine pericardial. Freedom from SVD at 10 years ranged from 58.9% to 100% and at 15 years from 58.3% to 93%. Freedom from reoperation ranged from 65% to 98.7% at 10 years and 78.5% to 91% at 15 years. Information on native valve pathology or dominant haemodynamic lesion was missing in 25% and 66% of studies, respectively. Reports of postoperative echocardiography were lacking, despite the heavy reliance on echocardiography for SVD diagnosis.

CONCLUSIONS

There is considerable variability in reporting bMVR long-term outcomes. As such, it is difficult to generate an unbiased, generalizable understanding of long- term outcomes after bMVR across the spectrum of mitral disease phenotypes.

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.

DURABILITY OF MITRAL VALVE REPLACEMENT WITH A 3RD GENERATION BIOPROSTHESIS

BACKGROUND

To evaluate the durability of a third-generation porcine bioprosthesis (Epic® valve) in the mitral position, according to patients' age at surgery.

METHODS

A total of 482 mitral valve replacements (MVR) using the Epic® valve at a single center were included (2009-2018). Perioperative and early postoperative data were prospectively collected. A systematic follow-up was performed (99% complete, 1,609.5 patient/years, average: 3.8 ± 2.5 years). Standardized definitions of valve-related events were adopted. Age at MVR was 68.1 ± 10.4 years.

RESULTS

Operative mortality was 9.3%. The were 5 early valve-related reoperations, mainly due to recurrent infectious endocarditis. Global survival at 8.8 years was 69.5% ± 5. There were 9 SVD events during the follow-up (3 receiving reoperations, 4 TMVR valve-in-valve, and 2 medical treatment only). The freedom from SVD at 5 and 10 years was 97.4% ± 1.2 and 89.6% ± 4.4 (actuarial), and 97.8% ± 1 and 91.9% ± 3.3, respectively (competing risks). After stratification into subgroups by age at surgery (≤59: 50.8%, 60-69: 32.8%, ≥70: 16.4%) there was no significant intergroup difference in freedom from SVD (log-rank p=0.24). The overall freedom from any reintervention for SVD at 10 years was 90.5% ± 4.4 (actuarial) and 92.7% ± 3.3 (competing risks), with no intergroup difference (log-rank p=0.14). The freedom from any valve-related complication at 8.4 years was 83.2% ± 4.5 (actuarial).

CONCLUSIONS

The Epic® bioprosthesis shows good durability at 5 to 10 years in the mitral position.

Late results after mitral valve replacement with Mosaic bioprosthesis in patients aged 65 years or younger

OBJECTIVES

Although in younger patients indications for biological prosthesis implantation in mitral valve replacement remain controversial, recently bioprostheses use increased considerably. We present late results obtained with the Medtronic Mosaic bioprosthesis in patients aged 65 years or younger.

METHODS

Between 2007 and 2017, 67 mitral Mosaic bioprostheses were implanted in patients aged 65 years or younger (58.5 ± 6.4 years). Follow-up extended up to 13 years. Survival, freedom from structural valve degeneration, endocarditis, thromboembolic events and reoperation were considered as main clinical end points evaluated at 1, 5 and 10 years.

RESULTS

The mean follow-up was 4.7 ± 2.8 years. Overall mortality rate was 12%. At 1, 5 and 10 years, survival was 94 ± 3%, 89 ± 4% and 77 ± 9%, respectively. Freedom from structural valve degeneration was 100%, 94 ± 4% and 71 ± 21%. Freedom from endocarditis was 95 ± 3%, 90 ± 6% and 84 ± 8%. Freedom from thromboembolic events was 94 ± 3%, 90 ± 5% and 90 ± 5%. Freedom from reoperation was 94 ± 3%, 87 ± 5% and 65 ± 19%.

CONCLUSIONS

Mosaic bioprosthesis appears a valid mitral valve substitute even when employed in ≤65-year-old patients.