Tissue Engineered Transcatheter Pulmonary Valved Stent Implantation: Current State and Future Prospect

Patients with the complex congenital heart disease (CHD) are usually associated with right ventricular outflow tract dysfunction and typically require multiple surgical interventions during their lives to relieve the right ventricular outflow tract abnormality. Transcatheter pulmonary valve replacement was used as a non-surgical, less invasive alternative treatment for right ventricular outflow tract dysfunction and has been rapidly developing over the past years. Despite the current favorable results of transcatheter pulmonary valve replacement, many patients eligible for pulmonary valve replacement are still not candidates for transcatheter pulmonary valve replacement. Therefore, one of the significant future challenges is to expand transcatheter pulmonary valve replacement to a broader patient population. This review describes the limitations and problems of existing techniques and focuses on decellularized tissue engineering for pulmonary valve stenting.

Is Porcine Small Intestinal Submucosal Extracellular Matrix (ECM) a Suitable Material for Right Ventricular Outflow Tract Reconstruction in Association With Pulmonary Valve Replacement?

Pulmonary valve replacement (PVR) with right ventricular outflow tract (RVOT) reconstruction is a common congenital cardiac operation. Porcine submucosal intestinal-derived extracellular matrix (ECM) patches have been used for RVOT reconstruction. We present 2 adult patients with Tetralogy of Fallot who underwent PVR with RVOT reconstruction utilizing ECM. Both cases required reoperation due to patch dehiscence causing a large paravalvular leak. One patient also had a pseudoaneurysm associated with ECM dehiscence. There may be a propensity for ECM dehiscence in this application and, based on these cases, we recommend avoidance of ECM in RVOT reconstruction with PVR. PVR patients repaired with ECM should be monitored for this complication.

Surgical and Transcatheter Pulmonary Valve Replacement: A Single Institution Comparison

Background and Hypothesis: Pulmonary valve replacement (PVR) is one of the most commonly performed procedures for patients with congenital heart disease. Transcatheter-based PVR (TPVR) approaches have emerged as alternatives to surgical pulmonary valve replacement (SPVR), but few studies have directly compared clinical outcomes between the two interventions. Further characterization of performance between the two valve procedures may inform clinical decision-making. Project Methods: Using institutional databases, we identified patients aged ≥ 9 years who underwent either a TPVR or SPVR at Riley Hospital for Children between January 2009 and June 2020. Exclusions were made for previous endocarditis diagnosis, <1 year follow-up, and concomitant left heart procedures. Valve dysfunction was defined as ≥ moderate regurgitation or gradient ≥ 40 mmHg. Results: 94 (TPVR, n=52; SPVR, n=42) patients met inclusion criteria. Average follow-up for SPVR and TPVR patients was 5.1(2.0,6.7) and 2.9(1.6,4.8) years, respectively (p=0.007). The SPVR cohort was younger, had lower BMI, and underwent more prior sternotomies. Hospital length of stay was shorter after TPVR (1.0 day vs. 5.0 days, p<0.001). Despite being younger, BSA-indexed valve size was larger in the SPVR cohort (14.7 mm/m2 vs 12.9 mm/m2, p<0.001). Short-term mortality (0% vs 2%, p=0.36), endocarditis (0% vs 6%, p=0.11), and reintervention (12% vs 8%, p=0.49) did not differ between groups. Intermediate-term valve dysfunction/failure was greater in SPVR patients (29% vs 12%, p=0.04) with time to dysfunction 809(421,1565) and 1184(181,1627) days for SPVR and TPVR, respectively. Valve implantation failure due to pre-stent migration occurred in 4% of TPVR cases; one required surgical intervention. Conclusion and Potential Impact: In patients undergoing PVR at our institution, rates of mortality and infective endocarditis are similar between interventions. Intermediate-term valve dysfunction/failure was greater in SPVR cohort, but length of follow-up was significantly longer in these patients. Reintervention rates were similar between procedures.

Tricuspid Valve Intervention at the Time of Pulmonary Valve Replacement in Adults With Congenital Heart Disease: A Systematic Review and Meta‐Analysis

Background Tricuspid regurgitation (TR) is a common finding in adults with congenital heart disease referred for pulmonary valve replacement (PVR). However, indications for combined valve surgery remain controversial. This study aimed to evaluate early results of concomitant tricuspid valve intervention (TVI) at the time of PVR. Methods and Results Observational studies comparing TVI+PVR and isolated PVR were identified by a systematic search of published research. Random‐effects meta‐analysis was performed, comparing outcomes between the 2 groups. Six studies involving 749 patients (TVI+PVR, 278 patients; PVR, 471 patients) met the eligibility criteria. In the pooled analysis, both TVI+PVR and PVR reduced TR grade, pulmonary regurgitation grade, right ventricular end‐diastolic volume, and right ventricular end‐systolic volumes. TVI+PVR, but not PVR, was associated with a decrease in tricuspid valve annulus size (mean difference, −6.43 mm, 95% CI, −10.59 to −2.27; P =0.010). Furthermore, TVI+PVR was associated with a larger reduction in TR grade compared with PVR (mean difference, −0.40; 95% CI, −0.75 to −0.05; P =0.031). No evidence could be established for an effect of either treatment on right ventricular ejection fraction or echocardiographic assessment of right ventricular dilatation and dysfunction. There was no evidence for a difference in hospital mortality or reoperation for TR. Conclusions While both strategies are effective in reducing TR and right ventricular volumes, routine TVI+PVR can reduce TR grade to a larger extent than isolated PVR. Further studies are needed to identify the subgroups of patients who might benefit most from combined valve surgery.