Aortic valve replacement in young patients: should the biological prosthesis be recommended over the mechanical?

Aortic Valve Replacement in Adult Patients with Decellularized Homografts: A Single-Center Experience

BACKGROUND

decellularized aortic homografts (DAH) represent a promising alternative for aortic valve replacement in young adults due to their low immunogenicity and thrombogenicity. Herein, we report our midterm, single-center experience in adult patients with non-frozen DAH from corlife.

METHODS

safety, durability, and hemodynamic performance were evaluated according to current guidelines in all consecutive patients who had received a DAH at our center since 03/2016.

RESULTS

seventy-three (mean age 47 ± 11 years, 68.4% (n = 50) male) patients were enrolled. The mean diameter of the implanted DAH was 24 ± 2 mm. Mean follow-up was 36 ± 27 months, with a maximum follow-up of 85 months and cumulative follow-up of 215 years. No cases of stenosis were observed, in four (5.5%) cases moderate aortic regurgitation occurred, but no reintervention was required. No cases of early mortality, non-structural dysfunction, reoperation, valve endocarditis, or thrombosis were observed. Freedom from bleeding and thromboembolic events was 100%; freedom from re-intervention was 100%; survival was 98.6% (n = 72).

CONCLUSIONS

early and mid-term results showed low mortality and 100% freedom from reoperation, thromboembolic events, and bleeding at our center. However, in order for this novel approach to be established as a valid alternative to aortic valve replacement in young patients, long-term data are required.

Perimount MAGNA Ease vs. INSPIRIS Resilia Valve: A PS-Matched Analysis of the Hemodynamic Performances in Patients below 70 Years of Age

BACKGROUND

During the past decade, the Perimount Magna Ease (PME) bioprosthesis has been implanted worldwide for aortic valve replacement (AVR). Recently, the INSPIRIS Resilia (IR) valve has been introduced as the newest generation of pericardial bioprostheses. However, few data have been reported about patients ≤70 years, and no comparisons in terms of hemodynamic performance between these two bioprostheses have been ever reported.

METHODS

Patients aged <70 years undergoing AVR were considered for comparison between PME (n = 238) and IR (n = 192). Propensity score (PS) matching was performed by logistic regression with adjustment for eight key baseline variables. The two prostheses were compared in terms of hemodynamic performances up to 3 years postoperatively. Sub-analysis according to prosthetic size-category was accomplished.

RESULTS

A total of 122 pairs with similar baseline characteristics were obtained from the PS-matching. The two prostheses showed comparable hemodynamic performances at one year (Gmean: 11.3 ± 3.5 mmHg vs. 11.9 ± 5.4 mmHg; p = 0.8) and at 3 years postoperatively (Gmean: 12.2 ± 7.9 mmHg vs. 12.8 ± 5.2 mmHg for; p = 0.3). The sub-analysis of size-category confirmed no statistical differences concerning the hemodynamic performances for each annulus size.

CONCLUSIONS

This first PS-matched analysis demonstrated that the newly developed IR valve achieves the same safety and efficacy of the PME valve during mid-term follow-up in patients aged <70 years.

Cytotoxicity of Xenogeneic Pericardium Preserved by Epoxy Cross-Linking Agents

The aim of the study was to assess the cytotoxic effect of xenopericardial biomaterial treated with di- and pentaepoxides on the cell cultures in vitro.

Materials and Methods

Samples of bovine and porcine pericardium were used in the work. Three different modes were employed for preservation: 1) 0.625% solution of glutaraldehyde (GA) and a two-fold change on days 2 and 7; 2) 5% solution of ethylene glycol diglycidyl ether (EGDE) changed on day 2; 3) 5% EGDE solution for 10 days, then 2% pentaepoxide solution also for 10 days. The cytotoxicity of the biomaterial was assessed by the extraction method. To determine the cytotoxicity of the biomaterial, EA.hy926 cells, multipotent mesenchymal stem cells (MMSCs), and fibroblasts were used. Cell viability was determined by the MTT test. The level of apoptosis and necrosis in the cell cultures was assessed by staining with acridine orange and ethidium bromide after cultivation with xenopericardial extracts employing different modes of preservation.

Results

Extracts of bovine and porcine pericardium preserved with GA have been found to have the greatest toxic effect on the cell cultures showing 20-33% reduction of cell viability. Extracts from bovine and porcine pericardium preserved with di- and pentaepoxy compounds do not have a toxic effect on endothelial cells, MMSCs, and fibroblasts since cell viability reduction is by no more than 15%. The lowest level of apoptosis and necrosis is observed in the cell cultures under the influence of extracts from the pericardium, preserved with diepoxide and pentaepoxide compounds.

Conclusion

According to the MTT test for cytotoxicity and determination of the level of apoptosis and necrosis in cell cultures, bovine and porcine pericardia treated with di- and pentaepoxides have been established to have no cytotoxic effect on the culture of endothelial EA.hy926 cells, MMSCs, fibroblasts in vitro, whereas GA, in comparison with di- and pentaepoxides, has a toxic impact on the cells.

Cross-linking method using pentaepoxide for improving bovine and porcine bioprosthetic pericardia: A multiparametric assessment study

Bioprosthetic heart valves made from bovine pericardium (BP) and porcine pericardium (PP) preserved with glutaraldehyde (GA) are commonly used in valve surgeries but prone to calcification in many patients. In this study, we compared BP and PP preserved with GA, ethylene glycol diglycidyl ether (DE), and 1,2,3,4,6-penta-O-{1-[2-(glycidyloxy)ethoxy]ethyl}-d-glucopyranose (PE). We studied the stabilities of DE and PE in preservation media along with the amino acid (AA) compositions, Fourier-transform infrared spectra, mechanical properties, surface morphologies, thermal stability, calcification, and the cytocompatibility of BP and PP treated with 0.625% GA, 5% DE, 2% PE, and alternating 5% DE and 2% PE for 3 + 11 d and 10 + 10 d, respectively. Both epoxides were stable in the water-buffer solutions (pH 7.4). DE provided high linkage densities in BP and PP owing to reactions with Hyl, Lys, His, Arg, Ser, and Tyr. PE reacted weakly with these AAs but strongly with Met. High cross-linking density obtained using the 10 d + 10 d method provided satisfactory thermal stability of biomaterials. The epoxy preservations improved cytocompatibility and resistance to calcification. PE enhanced the stress/strain properties of the xenogeneic pericardia, perhaps by forming nanostructures that were clearly visualised in BP using scanning electron microscopy. The DE + PE combination, in an alternating cross-linking manner, thus constitutes a promising option for developing bioprosthetic pericardia.

Severe structural deterioration of small aortic bioprostheses treated with valve-in-valve transcatheter aortic valve implantation

OBJECTIVES

The aim of this study was to evaluate outcomes of valve-in-valve transcatheter aortic valve implantation (VIV-TAVI) in patients with degenerated small bioprostheses.

METHODS

Outcomes of consecutive 27 high-risk patients (logistic EuroSCORE 35.5 ± 18.5%) with a mean age of 81.0 ± 5.9 years who underwent VIV-TAVI for degenerated small bioprostheses (19 mm-11.1%; 20 mm-11.1%; 21 mm-77.8%) were analyzed. Medtronic CoreValve (n = 11) or CoreValve Evolut-R prostheses (n = 16) were implanted. Follow-up was 3.2 ± 2.0 years.

RESULTS

Early mortality was 11.1%. One patient died intraoperatively due to left ventricle perforation, two others during the in-hospital period as a result of sudden cardiac death and pulmonary embolism. VIV-TAVI was completed in 26 cases (96.3%-success rate). Two patients required pacemaker implantation. Acute kidney injury occurred in two other patients. At discharge, mean transvalvular gradient was 19.2 ± 9.5 mmHg and in 25.9% of patients mean gradient exceeded 20 mmHg. Overall mortality was 25.9% and mortality from cardiac or unknown causes at 18.5%. Ninety percent of survivors were in New York Heart Association (NYHA) class I or II.

CONCLUSIONS

Transfemoral VIV-TAVI in patients with small, degenerated bioprostheses appears to be a promising alternative to surgery. Although the vast majority of patients have significant improvement in their NYHA class, the rate of persistent, residual gradients is relatively high and will need to be followed closely with serial echocardiograms.