scholarly journals Using contracting band to improve right ventricle ejection fraction for patients with repaired tetralogy of Fallot: A modeling study using patient-specific CMR-based 2-layer anisotropic models of human right and left ventricles

2013 ◽  
Vol 145 (1) ◽  
pp. 285-293.e2 ◽  
Author(s):  
Chun Yang ◽  
Dalin Tang ◽  
Tal Geva ◽  
Rahul Rathod ◽  
Haruo Yamauchi ◽  
...  
Author(s):  
Chun Yang ◽  
Dalin Tang ◽  
Tal Geva ◽  
Rahul Rathod ◽  
Haruo Yamauchi ◽  
...  

Patients with repaired Tetralogy of Fallot (ToF) account for the majority of cases with late onset right ventricle (RV) failure. The current surgical approach, which includes pulmonary valve replacement/insertion (PVR), has yielded mixed results [1–2]. A new surgical option placing an elastic band in the right ventricle is proposed to improve RV cardiac function measured by ejection fraction (EF).


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J Rodriguez Garcia ◽  
A Pijuan Domenech ◽  
J Perez Rodon ◽  
B Benito Villabriga ◽  
J Francisco Pascual ◽  
...  

Abstract Introduction Patients with repaired tetralogy of Fallot (rTF) and severe pulmonary regurgitation frequently progress to dilation and dysfunction of the right ventricle (RV). It has been documented in the literature that there is a correlation between the duration of the QRS in the surface electrocardiogram and the hemodynamic parameters of the RV of these patients, suggesting the presence of a mechanical-electrical interaction. Purpose To determine if there is an association between the contraction delay in certain areas of the RV measured in M-mode echocardiography and the delay in electrical activation measured in the electroanatomic map (EAM) of RV in patients with rTF. Methods Unicentric and observational study of all patients with rTF undergoing EAM, echocardiography with study of RV asynchrony and cardiac magnetic resonance imaging (MRI). Activation delay in the antero-basal area and in the RV outflow tract (RVOT) in the EAM were both analysed (Figure 1A). The shortening delay in the same areas in M-mode echocardiography was also evaluated (Figure 1B, C). MRI data regarding volume and ejection fraction was also collected. Results 64 patients were included (36.7±10.6 years, 65% men). The mean total activation time of the RV (RV-TAT) was 127.3±42.4 ms. Activation mapping showed a recurrent pattern with beginning in the interventricular septum and ending in RV antero-basal region and/or RVOT. A linear positive correlation was observed between RV-TAT and the activation delay in both regions analysed (ρ=0.60 and ρ=0.52, respectively; p<0.001) and also between the electrical and mechanical delay in the anterior wall (ρ=0.41; p=0.001). On the other hand, it was observed a negative correlation between RV ejection fraction (RVEF), measured on MRI, and the RV-TAT (ρ=−0.41, p=0.002) and also between RVEF and the activation delay in the RV antero-basal region and in the RVOT (ρ=−0.32, p=0.016 and ρ=−0.36, p=0.007, respectively). Conclusions There is a mechanical-electrical interaction in the RV of patients with rTF, with a negative correlation between the activation delay and RVEF and between mechanical and electrical activation delay in specific anatomical regions (regional mechanical-electrical interaction). These results may guide future studies on resynchronization in this heart disease. Figure 1. EAM and echocardiographic measures Funding Acknowledgement Type of funding source: None


Author(s):  
Han Yu ◽  
Pedro J. del Nido ◽  
Tal Geva ◽  
Chun Yang ◽  
Zheyang Wu ◽  
...  

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.


2022 ◽  
pp. 1-9
Author(s):  
Ayşe G. Eroğlu ◽  
Selman Gökalp ◽  
Sezen U. Atik ◽  
Damla Önal ◽  
Hazal C. Acar ◽  
...  

Abstract Aim: The left and right ventricular dysfunction are important clinical course indicators in patients with repaired tetralogy of Fallot. This study aimed to evaluate ventricular volumes, functions, and myocardial deformation in children with repaired tetralogy of Fallot by real-time three-dimensional (four-dimensional) echocardiography and compared with healthy children. It also aimed to investigate the relationships between ventricular volumes, functions, and myocardial deformation parameters in the patients. Materials and methods: In this cross-sectional study, 35 patients (mean age 15.1 ± 2.8 years, 54% male) and 35 healthy controls of similar age, gender, and body measurements underwent echocardiography. End-diastolic volume index, end-systolic volume index, and ejection fractions of both ventricles; global longitudinal, circumferential, radial strain, twist, and torsion of the left ventricle; the longitudinal strain of the right ventricle free wall and septum were measured. Results: Left ventricular ejection fraction, global circumferential and radial strain, twist and torsion were significantly lower in patients compared with controls. Left ventricular ejection fraction correlated with global circumferential (r = −0.446, p < 0.001) and radial strain (r = −0.433, p < 0.001) in the patients. Right ventricular volumes were significantly higher, and ejection fraction was significantly lower in patients compared with controls. All right ventricular parameters correlated with each other in the patients. Conclusion: Left ventricular contraction pattern was changed, circumferential and radial fibres were most affected in the patients. Right ventricular dilatation and dysfunction were detected, and right ventricular ejection fraction correlated well with strain measurements of the right ventricle.


2017 ◽  
Vol 28 (01) ◽  
pp. 034-038 ◽  
Author(s):  
Paloma Triana Junco ◽  
Monserrat Bret ◽  
Manuel Gomez Cervantes ◽  
Martha Muñoz Romo ◽  
Javier Jimenez Gomez ◽  
...  

Aim Cardiac function can be impaired in patients with pectus excavatum (PE) due to anatomic and dynamic compression of the heart. Efforts for radiation dose reduction in imaging techniques have allowed cardiac magnetic resonance imaging (c-MRI) to play a major role in PE assessment. The aim of our study is to describe the findings of c-MRI 18 months after we changed the PE assessment protocol from chest computed tomography to c-MRI. Patients and Methods Since mid-2015 all patients with severe PE (suspected Haller's index > 3.2) were assessed with inspiratory and expiratory c-MRI. A retrospective analysis of these patients was performed evaluating the following parameters: (1) Radiologic PE indexes (Haller's, correction and asymmetry indexes; and sternal rotation) and (2) cardiac function (including left and right ventricle ejection fraction). Results A total of 20 patients met the inclusion criteria. Dynamic imaging showed a significant difference during inspiration and expiration of the Haller's index 3.85 (range: 3.17–7.3) versus 5.10 (range: 3.85–10.8) (p < 0.05), and correction index (26.86% vs. 36.84%, respectively, p < 0.05). The sternal rotation was 14.5 (range: 0–36). c-MRI analysis disclosed a right ventricle ejection fraction of 50.3%. (normal range: 61% [54–71%]). Echocardiographic imaging underestimated the functional repercussion of PE in all patients. Conclusion Initial results show that PE assessment by c-MRI allows a radiation-free image of the chest wall deformity during the entire breathing process. Also, it permitted the evaluation of the influence of sternum impingement on cardiac function. These findings allowed us a careful surgical evaluation and preoperative planning.


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