scholarly journals Right Ventricle Has Normal Myofilament Function But Shows Perturbations in the Expression of Extracellular Matrix Genes in Patients With Tetralogy of Fallot Undergoing Pulmonary Valve Replacement

2020 ◽  
Vol 9 (16) ◽  
Author(s):  
Daniel Brayson ◽  
So‐Jin Holohan ◽  
Sonya C. Bardswell ◽  
Matthew Arno ◽  
Han Lu ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Right Ventricle ◽  
Tetralogy Of Fallot ◽  
Valve Replacement ◽  
Pulmonary Valve ◽  
Pulmonary Valve Replacement ◽  
Collagen Content ◽  
Valve Regurgitation ◽  
Tissue Samples ◽  
Pulmonary Valve Regurgitation

Background Patients with repair of tetralogy of Fallot (rToF) who are approaching adulthood often exhibit pulmonary valve regurgitation, leading to right ventricle (RV) dilatation and dysfunction. The regurgitation can be corrected by pulmonary valve replacement (PVR), but the optimal surgical timing remains under debate, mainly because of the poorly understood nature of RV remodeling in patients with rToF. The goal of this study was to probe for pathologic molecular, cellular, and tissue changes in the myocardium of patients with rToF at the time of PVR. Methods and Results We measured contractile function of permeabilized myocytes, collagen content of tissue samples, and the expression of mRNA and selected proteins in RV tissue samples from patients with rToF undergoing PVR for severe pulmonary valve regurgitation. The data were compared with nondiseased RV tissue from unused donor hearts. Contractile performance and passive stiffness of the myofilaments in permeabilized myocytes were similar in rToF‐PVR and RV donor samples, as was collagen content and cross‐linking. The patients with rToF undergoing PVR had enhanced mRNA expression of genes associated with connective tissue diseases and tissue remodeling, including the small leucine‐rich proteoglycans ASPN (asporin), LUM (lumican), and OGN (osteoglycin), although their protein levels were not significantly increased. Conclusions RV myofilaments from patients with rToF undergoing PVR showed no functional impairment, but the changes in extracellular matrix gene expression may indicate the early stages of remodeling. Our study found no evidence of major damage at the cellular and tissue levels in the RV of patients with rToF who underwent PVR according to current clinical criteria.

scholarly journals Pulmonary Valve Replacement in Adult Patients With a Severely Dilated Right Ventricle and Refractory Arrhythmias After Repair of Tetralogy of Fallot

2009 ◽  
Vol 73 (11) ◽  
pp. 2135-2142 ◽  
Author(s):  
Aya Miyazaki ◽  
Masaki Yamamoto ◽  
Heima Sakaguchi ◽  
Shinya Tsukano ◽  
Koji Kagisaki ◽  
...  
Keyword(s):  
Right Ventricle ◽  
Tetralogy Of Fallot ◽  
Valve Replacement ◽  
Pulmonary Valve ◽  
Pulmonary Valve Replacement ◽  
Adult Patients

scholarly journals A Novel Pulmonary Valve Replacement Surgery Strategy Using Contracting Band for Patients With Repaired Tetralogy of Fallot: An MRI-Based Multipatient Modeling Study

2021 ◽  
Vol 9 ◽  
Author(s):  
Han Yu ◽  
Pedro J. del Nido ◽  
Tal Geva ◽  
Chun Yang ◽  
Zheyang Wu ◽  
...  
Keyword(s):  
Ejection Fraction ◽  
Right Ventricle ◽  
Tetralogy Of Fallot ◽  
Valve Replacement ◽  
Pulmonary Valve ◽  
Pulmonary Valve Replacement ◽  
Repaired Tetralogy Of Fallot ◽  
Active Contraction ◽  
Contraction Ratio ◽  
Rv Function

Patients with repaired Tetralogy of Fallot (ToF), a congenital heart defect which includes a ventricular septal defect and severe right ventricular outflow obstruction, account for the majority of cases with late-onset right ventricle (RV) failure. Current surgery procedures, including pulmonary valve replacement (PVR) with right ventricle remodeling, yield mixed results. PVR with active band insertion was hypothesized to be of clinical usage on improving RV function measured by ejection fraction (EF). In lieu of risky open-heart surgeries and experiments on animal and human, computational biomechanical models were adapted to study the impact of PVR with five band insertion options. Cardiac magnetic resonance (CMR) images were acquired from seven TOF patients before PVR surgery for model construction. For each patient, five different surgery plans combined with passive and active contraction band with contraction ratio of 20, 15, and 10% were studied. Those five plans include three single-band plans with different band locations; one plan with two bands, and one plan with three bands. Including the seven no-band models, 147 computational bi-ventricle models were constructed to simulate RV cardiac functions and identify optimal band plans. Patient variations with different band plans were investigated. Surgery plan with three active contraction bands and band active contraction ratio of 20% had the best performance on improving RV function. The mean ± SD RV ejection fraction value from the seven patients was 42.90 ± 5.68%, presenting a 4.19% absolute improvement or a 10.82% relative improvement, when compared with the baseline models (38.71 ± 5.73%, p = 0.016). The EF improvements from the seven patients varied from 2.87 to 6.01%. Surgical procedures using active contraction bands have great potential to improve RV function measured by ejection fraction for patients with repaired ToF. It is possible to have higher right ventricle ejection fraction improvement with more bands and higher band active contraction ratio. Our findings with computational models need to be further validated by animal experiments before clinical trial could become possible.

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