Whether Pulmonary Valve Replacement in Asymptomatic Patients With Moderate or Severe Regurgitation After Tetralogy of Fallot Repair Is Appropriate: A Case-Control Study

Pulmonary Valve Replacement Timing Following Initial Tetralogy of Fallot Repair: A Systematic Review

Pulmonary valve replacement (PVR) is a critical aspect of surgical management for patients with tetralogy of Fallot (ToF). Determining an optimal timeframe for intervention is imperative, as it directly impacts long-term outcomes and the risk of complications in ToF patients. Ventriculotomy with the transannular patch is currently indicated for right ventricular outflow tract obstruction, but the patch itself can lead to pulmonary regurgitation (PR), dyspnea, and cyanosis, among other complications. This investigation seeks to establish an evidence-based timeline to enhance the overall quality of care for individuals with this congenital heart condition. From 2002 to 2022, 21,935 articles regarding the PVR timing for ToF were examined and filtered. The publications were screened using PRISMA guidelines, and 32 studies were included for analysis and review. Among the studies, PVR was strongly indicated for patients who had developed severe PR, especially in asymptomatic patients and those experiencing fatigue and exercise intolerance. Severe PR was associated with arrhythmias such as right bundle branch block, atrioventricular block, and prolonged QRS intervals, in which male sex and high right ventricular end-diastolic volume (RVEDV) were significant predictors of long preoperative QRS duration. Most physicians found RVEDV necessary for making surgical referrals despite a lack of correlation between PR severity and RVEDV or indexed right ventricular end-systolic volume (RVESVi). However, asymptomatic ToF patients with preoperative RVESVi benefited from PVR. Except for some variations in QRS intervals among studies, arrhythmias tended to persist post-op, yet NYHA functional class and RV size improved significantly following PVR. Older age at PVR was found to be associated with adverse cardiac events, whereas early PVR presented with appropriately short QRS intervals. Cardiac function tended to be significantly worse in patients undergoing late PVR versus early PVR, with timelines ranging from one to three decades following initial ToF repair. Choosing the best timeline for PVR largely depends on the patient's baseline cardiopulmonary presentation, and additional quantitative deformation analysis can help predict an appropriate timeline for ToF patients.

Improving long-term care and outcomes of congenital heart disease: fulfilling the promise of a healthy life

Advances in the prevention, diagnosis, and treatment for congenital heart disease (CHD), the most common birth defect in China, have drastically improved survival for individuals with the disease. However, China's current health system is not well prepared to manage the growing population of people with CHD and their complex medical needs, which range from early detection of the condition and intervention for physical, neurodevelopmental, and psychosocial impairment, to long-term management of major complications and chronic health problems. Health disparities caused by long-standing regional differences in access to care pose challenges when major complications such as pulmonary hypertension arise, and when individuals with complex CHD become pregnant and give birth. Currently, no data sources track neonates, children, adolescents, and adults with CHD in China and delineate their clinical characteristics and use of health resources. This scarcity of data should warrant attention from the Chinese Government and relevant specialists in the field. In the third paper of the Series on CHD in China, we summarise key literature and current data to identify knowledge gaps and call for concerted efforts by the government, hospitals, clinicians, industries, and charitable organisations to develop an actionable, lifelong framework of congenital cardiac care that is accessible and affordable for all individuals with CHD. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Current treatment outcomes of congenital heart disease and future perspectives

China has the largest number of individuals with congenital heart disease (CHD) in the world and a heavy burden of CHD. Therefore, understanding current CHD treatment outcomes and patterns in China will contribute to global progress in CHD treatment and be a valuable experience. Generally, CHD treatment in China has satisfactory outcomes owing to the joint efforts by all relevant stakeholders across the country. However, efforts are needed to overcome the remaining challenges: management of mitral valve disease and paediatric end-stage heart failure needs to be improved; cohesive paediatric cardiology teams should be established and collaboration between hospitals enhanced; CHD-related medical resources need to be more accessible and equitable; and nationwide CHD databases should be enhanced. In the second paper of this Series, we aim to systematically summarise the current CHD treatment outcomes in China, discuss potential solutions, and provide future perspectives.

Biopsy-detected myocardial fibrosis predicts adverse cardiac events after pulmonary valve replacement in patients with repaired tetralogy of Fallot

OBJECTIVES

Risk factors associated with adverse cardiac events (cardiac AEs) after pulmonary valve replacement (PVR) in patients with repaired tetralogy of Fallot are incompletely understood. In this study, we aimed to determine the relationship between histological myocardial fibrosis and cardiac AEs after PVR in patients with rTOF.

METHODS

We consecutively collected clinical, cardiac magnetic resonance, echocardiography and electrocardiogram data of 51 patients with rTOF who underwent surgical PVR. The right ventricular outflow tract tissue was collected during the PVR and the degree of histological myocardial fibrosis was determined by a tailor-made automated image analysis method of picrosirius red staining.

RESULTS

The median follow-up time was 4.9 years, and 14 patients had cardiac AEs (a composite of heart failure admission and arrhythmia) during follow-up. The total analysis area of myocardial samples was 5782.18 mm2, and the median percentage of myocardial fibrosis was 20.6% (interquartile range 16.7-27.0%), which were significantly elevated in patients with cardiac AEs compared with patients without cardiac AEs (24.1% vs 19.7%, P = 0.007). Right ventricular ejection fraction and left ventricular end-systolic volume index were significantly associated with myocardial fibrosis in multivariable stepwise linear regression analysis (R2 = 0.238). Cox proportional hazards regression identified degree of myocardial fibrosis [hazard ratio 1.127; 95% confidence interval (CI) 1.047-1.213; P = 0.001] and age at PVR (hazard ratio 1.062; 95% CI 1.010-1.116; P = 0.019) were associated with increased risk of cardiac AEs. The incidence of adverse cardiac events was significantly increased when myocardial fibrosis >20.1% and age at PVR >18.2 years.

CONCLUSIONS

Histological myocardial fibrosis was associated with biventricular systolic functions in rTOF. Higher myocardial fibrosis and older age at PVR are independent risk factors for the adverse cardiac events after PVR in patients with rTOF.

Biventricular shape modes discriminate pulmonary valve replacement in tetralogy of Fallot better than imaging indices

Current indications for pulmonary valve replacement (PVR) in repaired tetralogy of Fallot (rTOF) rely on cardiovascular magnetic resonance (CMR) image-based indices but are inconsistently applied, lead to mixed outcomes, and remain debated. This study aimed to test the hypothesis that specific markers of biventricular shape may discriminate differences between rTOF patients who did and did not require subsequent PVR better than standard imaging indices. In this cross-sectional retrospective study, biventricular shape models were customized to CMR images from 84 rTOF patients. A statistical atlas of end-diastolic shape was constructed using principal component analysis. Multivariate regression was used to quantify shape mode and imaging index associations with subsequent intervention status (PVR, n = 48 vs. No-PVR, n = 36), while accounting for confounders. Clustering analysis was used to test the ability of the most significant shape modes and imaging indices to discriminate PVR status as evaluated by a Matthews correlation coefficient (MCC). Geometric strain analysis was also conducted to assess shape mode associations with systolic function. PVR status correlated significantly with shape modes associated with right ventricular (RV) apical dilation and left ventricular (LV) dilation (p < 0.01), RV basal bulging and LV conicity (p < 0.05), and pulmonary valve dilation (p < 0.01). PVR status also correlated significantly with RV ejection fraction (p < 0.05) and correlated marginally with LV end-systolic volume index (p < 0.07). Shape modes discriminated subsequent PVR better than standard imaging indices (MCC = 0.49 and MCC = 0.28, respectively) and were significantly associated with RV and LV radial systolic strain. Biventricular shape modes discriminated differences between patients who did and did not require subsequent PVR better than standard imaging indices in current use. These regional features of cardiac morphology may provide insight into adaptive vs. maladaptive types of structural remodeling and point toward an improved quantitative, patient-specific assessment tool for clinical use.

Left ventricular strain derived from cardiac magnetic resonance can predict outcomes of pulmonary valve replacement in patients with repaired tetralogy of Fallot

Purpose

Several adults with repaired tetralogy of Fallot (rToF) undergo pulmonary valve replacement (PVR) to reduce the right ventricular volume and retain right ventricular function. However, there is currently no consensus on the ideal time for PVR surgery in asymptomatic patients with rTOF with pulmonary regurgitation (PR). Clinical outcomes after PVR are also indeterminate. Recently, myocardial strain and strain rate derived from cardiac magnetic resonance (CMR) feature tracking were found to be more sensitive to right ventricular dysfunction than conventional parameters and therefore may add prognostic value in patients with rToF. We aimed to analyze whether pre-PVR left ventricular (LV) strain and strain rate detected by CMR feature tracking are associated with midterm outcomes after PVR in patients with rToF.

Methods

Seventy-eight asymptomatic patients with rToF who required PVR due to moderate or severe PR were prospectively enrolled between January 2014 and June 2020. CMR cine sequences were obtained, and feature tracking parameters were measured preoperatively. Adverse events were documented during the follow-up. Receiver operating characteristic analysis was performed to determine the cutoff value. Kaplan–Meier curves were drawn with log-rank statistics; moreover, univariate and multivariate Cox proportional hazards regression analyses and Harrel C-indices were analyzed.

Results

During 3.6 ± 1.8 years of follow-up, 25 adverse events were recorded. Kaplan–Meier survival curves and univariate Cox analysis verified that patients with significantly reduced radial strain (RS), circumferential strain (CS), longitudinal strain (LS), RS rate at systole and diastole (RSRs and RSRe), and circumferential and LS rates at diastole (CSRe and LSRe) had worse event-free survival. After multivariate correction, only LS and LSRe remained significantly associated with adverse outcomes (hazard ratio = 1.243 [1.083–1.428] and 0.067 [0.017–0.258], respectively, all p &lt; 0.05). The cutoff values of LS and LSRe were −12.30 (%) and 1.07 (s–1), respectively.

Conclusion

The LV strain and strain rate prior to PVR are important prognostic factors for adverse events after PVR in rToF.

Cardiac MRI predictors of good long-term outcomes in patients with repaired TOF

BACKGROUND

Risk stratification in patients with repaired tetralogy of Fallot (rTOF) have focused on poor clinical outcomes while predictors of a benign clinical course have not been characterized.

OBJECTIVE

The goal of this study was to Identify cardiac magnetic resonance (CMR) markers of a good clinical course late after TOF repair.

METHODS

Clinical and CMR data from the International Multicenter TOF Registry (INDICATOR) were analyzed. The primary outcome was time to the earliest occurrence of a composite of death, aborted sudden death, and sustained ventricular tachycardia (VT). The secondary outcome was time to the earliest occurrence of atrial arrhythmia, nonsustained VT, and NYHA class >II. Multinomial regression was used to identify predictors of the 3-category outcome: (a) good outcome, defined as freedom from the primary AND secondary outcomes at age 50 years; (b) poor outcome, defined as presence of the primary outcome before age 50 years; and (c) intermediate outcome, defined as not fulfilling criteria for good or poor outcomes.

RESULTS

Among 1088 eligible patients, 96 had good outcome, 60 experienced poor outcome, and 932 had intermediate outcome. Patients were age 25.8±10.8 years at the time of the index CMR. Median follow-up was 5.8 years (IQR 3.0, 9.9) after CMR in event-free patients. By univariate analysis, smaller right ventricular (RV) end-systolic and end-diastolic volume index, smaller left ventricular end-systolic volume index, higher right and left ventricular ejection fraction, lower right and left ventricular mass index, and lower left ventricular mass/volume ratio were associated with good outcome. Multivariable modeling identified higher RV ejection fraction (OR 2.38 per 10% increase, P = .002) and lower RV mass index (OR 1.72, per 10 g/m2 decrease, P = .002) as independently associated with good outcome after adjusting for age at CMR. Classification and regression tree analysis identified important thresholds associated with good outcome that were specific to patients age ≥37 years at the time of CMR; these were RV ejection fraction ≥42% and RV mass index <39 g/m2.

CONCLUSIONS

Adults with rTOF and no more than mild RV dysfunction combined with no significant RV hypertrophy are likely to be free from serious adverse clinical events into their sixth decade of life and may require less frequent cardiac testing.

Pulmonary Valve Replacement in Repaired Tetralogy of Fallot: Midterm Impact on Biventricular Response and Adverse Clinical Outcomes

BACKGROUND

Pulmonary regurgitation (PR), though well tolerated for short term in patients with repaired tetralogy of Fallot (rTOF), could lead to right ventricular (RV) dysfunction, arrhythmias, and sudden cardiac death. Pulmonary valve replacement (PVR), considered as the gold-standard treatment for PR, is performed to mitigate these late effects. In this study, we aimed to evaluate the midterm outcomes and predictors of adverse clinical outcomes (ACO).

METHODS

From May 2014 to December 2017, 42 patients with rTOF undergoing surgical or transcatheter PVR in our department were retrospectively included. Cardiovascular magnetic resonance was performed before PVR (pre-PVR), early after PVR (early post-PVR), and midterm after PVR (midterm post-PVR). Medical history and individual data were collected from medical records. ACO included all-cause death, new-onset arrhythmia, prosthetic valve failure, and repeat PVR.

RESULTS

The median follow-up duration was 4.7 years. PVR was performed at a median age of 21.6 years. There was no early or late death. Freedom from ACO at 3 and 5 years was 88.1 ± 5% and 58.2 ± 9%, respectively. RV end-diastolic volume index (RVEDVI) and end-systolic volume index (RVESVI) significantly reduced early after PVR and further decreased by midterm follow-up (pre-PVR vs. early post-PVR vs. midterm post-PVR: RVEDVI, 155.2 ± 34.7 vs. 103.8 ± 31.2 vs. 95.1 ± 28.6 ml/m², p < 0.001; RVESVI, 102.9 ± 28.5 vs. 65.4 ± 28.2 vs. 57.7 ± 23.4 ml/m², p < 0.001). Multivariable analysis revealed that the occurrence of ACO was significantly increased in patients with lower left ventricular end-systolic volume index.

CONCLUSIONS

A significant reduction of RV volume occurred early after PVR, followed by a further improvement of biventricular function by midterm follow-up. The midterm freedom from ACO was favorable.

Concomitant pulmonary valve replacement with intracardiac repair for adult tetralogy of Fallot

Objectives :

Adult patients undergoing tetralogy of Fallot (TOF) repair have a higher risk of mortality compared to pediatric patients. Pulmonary regurgitation (PR) further predisposes these patients to heart failure, arrhythmias, and sudden death. Pulmonary valve replacement (PVR) may improve the symptoms in these patients but, fails to reverse the other deleterious effects. Aim of our study was to evaluate the effect of concomitant PVR with TOF repair on right ventricular (RV) parameters, cardiopulmonary exercise capacity, and bioprosthetic valve durability at mid-term.

Materials and Methods:

Between January 2013 and August 2018, 37 adolescents and adults with TOF who had hypoplastic pulmonary annulus underwent concomitant TOF repair with PVR at our institute. We retrospectively collected the data from the hospital records including follow-up.

Results :

Mean age of the patients was 18.48 ± 7.53 years. Bioprosthetic valve size ranged from 19 mm to 25 mm. There was no early or late mortality. No patient had developed significant perioperative complications. At a mean follow-up of 53.3 ± 16.4 months, there was no significant change in mean QRS duration, RV function, RV end-systolic and end-diastolic dimensions, RV myocardial performance index, and functional status (including NYHA class and 6-min walk test) compared to at-discharge values. Four patients developed prosthetic valve degeneration with mild PR and without significant increase in gradient.

Conclusion :

Concomitant PVR with TOF repair in adult provides excellent mid-term outcome, with a minimal rate of pulmonary valve degeneration. It not only eases the early postoperative course but also preserves the RV function as well as functional status at mid-term.

Whether Pulmonary Valve Replacement in Asymptomatic Patients With Moderate or Severe Regurgitation After Tetralogy of Fallot Repair Is Appropriate: A Case-Control Study

Background

Although right ventricular (RV) volume was significantly decreased in symptomatic patients with repaired tetralogy of Fallot (rTOF) after pulmonary valve replacement (PVR), RV size was still enlarged along with RV dysfunction.

Methods and Results

A prospective case‐control study was conducted in a tertiary hospital; 81 asymptomatic repaired tetralogy of Fallot patients with moderate or severe pulmonary regurgitation were enrolled. The enrolled cohort was divided into 2 groups: PVR group (n=41) and medication group (n=40). Cardiac magnetic resonance, transthoracic echocardiography, and electrocardiography were scheduled after recruitment and 6 months after PVR or recruitment. Adverse events were recorded during follow‐up. Three deaths, 1 heart transplantation, 3 PVRs, and 2 symptomatic heart failures in medication group and 1 redo PVR in the PVR group were observed during follow‐up. Compared with the medication group, the PVR group had significantly lower adverse events rate (P=0.023; odds ratio, 0.086; 95% CI, 0.010–0.716), and RV function was significantly improved (P<0.05). Binary logistic regression analysis identified preoperative RV end‐systolic volume index (10‐mL/m² increment, P=0.009; odds ratio, 0.64; 95% CI, 0.457–0.893) was an independent predictor of normalization of RV size after PVR. A preoperative RV end‐systolic volume index cut‐off value of 120 mL/m² (area under curve, 0.819; sensitivity, 90.3%; specificity, 70%) was analyzed by receiver operating characteristic curves for normalized RV size after PVR.

Conclusions

PVR in asymptomatic repaired tetralogy of Fallot patients is appropriate and effective in reducing right ventricular size and preserving right ventricular function. The recommended criterion of RV end‐systolic volume index for PVR is 120 mL/m².

Right ventricular failure in congenital heart disease

PURPOSE OF REVIEW

We aim to review select literature pertaining to congenital heart disease (CHD)-induced right ventricular (RV) function and failure.

RECENT FINDINGS

We review recent findings pertaining to children and adults with repaired tetralogy of Fallot (rTOF), systemic RV and hypoplastic left heart syndrome (HLHS). We emphasize pathophysiological mechanisms contributing to RV dysfunction in these conditions, the risk factors for adverse outcomes and the continuing challenges in treating these patients. We discuss how recent pathology findings, as well as developments in imaging and computer modeling have broadened our understanding of the pathophysiology of these conditions. We further review developments in the molecular and cellular basis of RV failure; and in particular, the RV molecular response to stress in repaired tetralogy of Fallot (rTOF). We highlight some of the genetic complexities in HLHS and how these may influence the long-term outcomes in these patients.

SUMMARY

Recent literature has led to new understandings in the pathology, pathophysiology, risk factors for adverse outcomes, molecular and genetic basis for RV dysfunction and failure in CHD. Although these findings provide new therapeutic targets, the treatment of RV failure at this time remains limited.