Valve Replacement In Tetralogy Research Articles

Pulmonary Valve Replacement in Tetralogy of Fallot: Procedural Volume and Durability of Bioprosthetic Pulmonary Valves

BackgroundRobust data on changes in pulmonary valve replacement (PVR) procedural volume and predictors of bioprosthetic pulmonary valve (BPV) durability in patients with tetralogy of Fallot (TOF) are scarce. ObjectivesThis study sought to assess temporal trends in PVR procedural volume and BPV durability in a nationwide, retrospective TOF cohort. MethodsData were obtained from patient records. Robust linear regression was used to assess temporal trends in PVR procedural volume. Piecewise exponential additive mixed models were used to estimate BPV durability, defined as the time from implantation to redo PVR with death as a competing risk, and to assess risk factors for reduced durability. ResultsIn total, 546 PVR were performed in 384 patients from 1976 to 2021. The annual number of PVR increased from 0.4 to 6.0 per million population (P < 0.001). In the last decade, the transcatheter PVR volume increased by 20% annually (P < 0.001), whereas the surgical PVR volume did not change significantly. The median BPV durability was 17 years (Q1: 10-Q3: 10 years-not applicable). There was no significant difference in the durability of different BPV after adjustment for confounders. Age at PVR (HR: 0.78 per 10 years from <1 year; 95% CI: 0.63-0.96; P = 0.02) and true inner valve diameter (9-17 mm vs 18-22 mm HR: 0.40; 95% CI: 0.22-0.73; P = 0.003 and 18-22 mm vs 23-30 mm HR: 0.59; 95% CI: 0.25-1.39; P = 0.23) were associated with reduced BPV durability in multivariate models. ConclusionsThe PVR procedural volume has increased over time, with a greater increment in transcatheter than surgical PVR during the last decade. Younger patient age at PVR and a smaller true inner valve diameter predicted reduced BPV durability.

Pulmonary valve replacement in tetralogy of Fallot - who and how?

Pulmonary regurgitation is the most common complication in repaired tetralogy of Fallot patients. Severe chronic pulmonary regurgitation can be tolerated for decades, but if not treated, it can progress to symptomatic, irreversible right ventricular dilatation and dysfunction. We investigated clinical associations with pulmonary valve replacement among patients with significative pulmonary regurgitation and how interventional developments can change their management. All adult patients with repaired tetralogy of Fallot who were followed at an adult CHD Clinic at a single centre from 1980 to 2022 were included on their first outpatient visit. Follow-up was estimated from the time of correction surgery until one of the following events occurred first: pulmonary valve replacement, death, loss to follow-up or conclusion of the study. We included 221 patients (116 males) with a median age of 19 (18-25). At a median age of 33 (10) years old, 114 (51%) patients presented significant pulmonary regurgitation. Among patients with significant pulmonary regurgitation, pulmonary valve replacement was associated with male gender, older age at surgical repair, and longer QRS duration in adulthood. Pulmonary valve replacement was performed in 50 patients, including four transcatheter pulmonary valve implantations, at a median age of 34 (14) years. Pulmonary regurgitation affects a large percentage of tetralogy of Fallot adult patients, requiring a long-term clinical and imaging follow-up. Sex, age at surgical repair and longer QRS are associated with the need of PVR among patients with significative pulmonary regurgitation. Clinical practice and current literature support TPVI as the future gold standard intervention.

From Other Journals: A Review of Recent Articles by Our Editorial Team.

In this review, we provide a brief description of recently published articles addressing topics relevant to pediatric cardiologists. This review includes (1) Fetal diagnosis, associated anomalies, and factors affecting outcomes in fetal congenitally corrected transposition of the great arteries (ccTGA), (2) The impact of Fontan-associated liver disease on heart and heart/liver transplant, (3) 1-year outcomes of the Harmony transcatheter pulmonary valve, (4) Risk factors associated with major adverse cardiac events in patients with pulmonary atresia and intact ventricular septum undergoing intervention, and (5) Benefits of pulmonary valve replacement in tetralogy of Fallot patients.

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.

Biventricular Pressure-Volume Loop Assessment Before and After Pulmonary Valve Replacement in Tetralogy of Fallot.

Patients with tetralogy of Fallot (TOF) may undergo pulmonary valve replacement (PVR) after initial full repair. We investigated indices of biventricular function, work and efficiency of TOF patients' using noninvasive pressure-volume (PV) loop analysis on cardiovascular magnetic resonance (CMR) images and compared pre-and post PVR groups. Biventricular segmentations of steady state free precession CMR images were performed using custom validated software (Segment version 2.0 R7067). Brachial cuff pressure estimated left ventricular (LV) systolic pressure. Right ventricular (RV) inputs were obtained from pre-PVR cardiac catheterization data. Biventricular PV loops were then derived using a time-varying elastance model. Twenty seven patients were studied: (22 pre-PVR, 5 post-PVR), mean age of 20±10.5 years and 83% male. RV stroke volume significantly differed before and after PVR (73.2±25 ml vs. 41±10 mL, P =0.01). RV stroke work (SW) and mean external power (MEP) were significantly less post-PVR, but there were no significant differences in the LV hemodynamic indices. TOF patients have reduced RV SW and MEP post-PVR suggesting improved hemodynamics. Noninvasive biventricular PV loop analysis shows potential for integration into standard CMR imaging of TOF and provides hemodynamic data that could influence management decisions.

Comparison of median sternotomy and left anterior mini-incision for pulmonary valve replacement following primary tetralogy of Fallot repair.

Pulmonary insufficiency requiring reintervention frequently occurs after primary tetralogy of Fallot repair. Repeat interventions present a challenge for both the surgeon and patient. We compare a minimally invasive, 5 cm left anterior mini-incision to redo median sternotomy for pulmonary valve replacement in tetralogy of Fallot patients. Following Internal Review Board approval, we conducted a single institution retrospective review of patients with tetralogy of Fallot who underwent pulmonary valve replacement via redo median sternotomy or left anterior mini-incision between 13 July, 2016 and 6 March, 2020. Twenty-three patients underwent pulmonary valve replacement following primary tetralogy of Fallot repair between March 2016 and March 2020. Twelve patients received a redo-median sternotomy from March 2016 to August 2018. Left anterior mini-incision was first offered in August of 2018 and was chosen by all eleven patients thereafter. The two groups had similar baseline characteristics including preoperative pulmonary valve dysfunction. Early trends suggest a longer cardiopulmonary bypass time for patients who received left anterior mini-incisions. Other outcomes were comparable, including operative times, blood product requirements, residual pulmonary valve dysfunction, postoperative pain, narcotic requirements, ICU length of stay, total length of stay, and postoperative complications. In patients who have previously undergone primary repairs of tetralogy of Fallot, outcomes for pulmonary valve replacement via left anterior mini-incision are comparable to those via redo median sternotomy.

Prediction of Ventricular Mechanics After Pulmonary Valve Replacement in Tetralogy of Fallot by Biomechanical Modeling: A Step Towards Precision Healthcare.

Clinical indicators of heart function are often limited in their ability to accurately evaluate the current mechanical state of the myocardium. Biomechanical modeling has been shown to be a promising tool in addition to clinical indicators. By providing a patient-specific measure of myocardial active stress (contractility), biomechanical modeling can enhance the precision of the description of patient's pathophysiology at any given point in time. In this work we aim to explore the ability of biomechanical modeling to predict the response of ventricular mechanics to the progressively decreasing afterload in repaired tetralogy of Fallot (rTOF) patients undergoing pulmonary valve replacement (PVR) for significant residual right ventricular outflow tract obstruction (RVOTO). We used 19 patient-specific models of patients with rTOF prior to pulmonary valve replacement (PVR), denoted as PSMpre, and patient-specific models of the same patients created post-PVR (PSMpost)-both created in our previous published work. Using the PSMpre and assuming cessation of the pulmonary regurgitation and a progressive decrease of RVOT resistance, we built relationships between the contractility and RVOT resistance post-PVR. The predictive value of such in silico obtained relationships were tested against the PSMpost, i.e. the models created from the actual post-PVR datasets. Our results show a linear 1-dimensional relationship between the in silico predicted contractility post-PVR and the RVOT resistance. The predicted contractility was close to the contractility in the PSMpost model with a mean (± SD) difference of 6.5 (± 3.0)%. The relationships between the contractility predicted by in silico PVR vs. RVOT resistance have a potential to inform clinicians about hypothetical mechanical response of the ventricle based on the degree of pre-operative RVOTO.

Right ventricular functional recovery depends on timing of pulmonary valve replacement in tetralogy of Fallot: a video kinematic study.

Indications for and timing of pulmonary valve replacement (PVR) after tetralogy of Fallot repair are controversial. Among magnetic resonance imaging indices proposed to time valve replacement, a right ventricular (RV) end-diastolic volume index greater than 160 ml/m2 is often used. Recent evidence suggests that this value may still identify patients with irreversible RV dysfunction, thus hindering recovery. Our goal was to define, using intraoperative video kinematic evaluation, whether a relationship exists between timing of PVR and early functional recovery after surgery. Between November 2016 and November 2018, a total of 12 consecutive patients aged 27.1 ± 19.1 years underwent PVR on average 22.2 ± 13.3 years after tetralogy of Fallot repair. Mean RV end-diastolic volume evident on the magnetic resonance images was 136.9 ± 35.7 ml/m2. Intraoperative cardiac kinematics were assessed by video kinematic evaluation via a high-speed camera acquiring videos at 200 fps before and after valve replacement. Patients presenting with RV end-diastolic volume <147 ml/m2 were significantly younger (11.2 ± 5.0 vs 38.4 ± 17.0; P = 0.005) and had a shorter time interval to valve replacement (11.0 ± 5.2 vs 30.1 ± 11.3; P = 0.03). The entire population showed a moderate correlation among energy expenditure, cardiac fatigue, perimeter of contraction and preoperative RV end-diastolic volume index. Both groups showed a reduction in all kinematic parameters after PVR, but those with end-diastolic volume >147 ml/m2 showed an unpredictable outcome. Video kinematic evaluation provides insight into intraoperative RV recovery in patients with tetralogy of Fallot undergoing PVR. Accordingly, functional recovery can be expected in patients with preoperative end-diastolic volume <147 ml/m2.

P4163Long term comparison between homograft vs stented bio-prostheses for pulmonary valve replacement in tetralogy of Fallot patients

Abstract Background Tetralogy of Fallot (TOF) repair results in long term chronic pulmonary regurgitation requiring pulmonary valve replacement (PVR). Homograft and stented bio-prosthesis are currently used for PVR but whether one should be considered superior to another remains unknown. Aim To compare echocardiographic and clinical outcomes after PVR with Homograft vs stented bioprosthesis in patients with previous TOF repair. Methods 137 patients who underwent PVR with stented bioproshesis were compared with 80 patients who received an homograft using Mixed linear model and multivariate Cox regression. Results Homograft were associated with a significantly lower transpulmonary gradient postoperatively (P=0.04) and after a mean follow-up 6 years (table). Homograft were associated with a significantly lower risk of reintervention (HR 0.24; 95% CI 0.07–0.85, p=0.026) while long term mortality was comparable between the two groups (P=0.1). Echocardiographic findings BIO HOMOGRAFT P N 137 80 Preoperatively TV regurgitation (mean, sd) 1.80 (0.63) 1.94 (0.81) 0.353 TV regurgitation pressure drop (mean,sd) 35.15 (15.49) 45.34 (25.24) 0.009 PV regurgitation (mean,sd) 3.63 (0.52) 3.34 (0.64) 0.004 PV systolic peak gradient (mean, sd) 25.07 (17.05) 30.68 (21.70) 0.138 Early postoperatively TV regurgitation (mean,sd) 1.52 (0.54) 1.54 (0.55) 0.858 TV regurgitation pressure drop (mean,sd) 30.10 (13.82) 29.13 (13.98) 0.733 PV regurgitation (mean,sd) 1.50 (0.54) 1.64 (0.53) 0.224 PV systolic peak gradient (mean,sd) 24.05 (11.10) 20.16 (14.19) 0.045 Latest follow_up TV regurgitation (mean,sd) 1.63 (0.61) 1.83 (0.80) 0.195 TV regurgitation pressure drop (mean,sd) 37.46 (18.84) 32.58 (13.47) 0.233 PV regurgitation (mean,sd) 2.06 (0.77) 2.07 (0.94) 0.982 PV systolic peak gradient (mean,sd) 32.22 (18.17) 21.25 (13.47) 0.001 TAPSE: Tricuspid annular plane systolic excursion; TV: tricuspid valve; PV: pulmonary valve. PV re-intervention Conclusions When compared to stented bio-prostheses, homografts were associated better early and late hemodynamic profile and a significantly lower risk of re-intervention. Homograft should be considered the first choice in patients undergoing PVR after TOF repair.

Trends and outcomes of pulmonary valve replacement in tetralogy of Fallot

BackgroundPulmonary valve replacement (PVR) is associated with improvement in symptoms and right ventricular remodeling in patients with tetralogy of Fallot (TOF). There are limited population-based data about outcomes after PVR. We therefore hypothesized a temporal increase in annual volume of PVR and decrease in in-hospital mortality after PVR in the United States. MethodsWe reviewed the National Inpatient Sample (NIS) for PVR performed in adults (>18 years) with TOF, 2000–2014. The primary outcome was trends in admissions for PVR, in-hospital mortality after PVR, and age at time of PVR. In order to assess trends, we divided the study period into tertiles: early era (2000–2004), mid era (2005–2009) and late era (2010–2014). ResultsThere were 18,353 admissions in adults with TOF diagnosis, of which PVR was performed in 1230 (6.7%), and 90 (7.3%) were transcatheter PVRs. The median age at PVR was 34 years and in-hospital mortality was 1.5%. Comparisons by study era showed temporal increase in the proportion of admissions for PVR (3.7% vs 6.3% vs 9.6%, p < 0.001), decrease in in-hospital mortality (4.1% vs 1.2% vs 0.8%, p = 0.002), and a decrease in age at the time of PVR (35.8 vs 33.8 vs 31.0 years, p < 0.001). ConclusionsThe proportion of admissions for PVR increased while in-hospital mortality and age at time of PVR decreased over time. A younger age at the time of PVR highlights important concerns and knowledge gaps about the cumulative lifetime risk of reinterventions and prosthetic valve endocarditis. Further studies are required to address these knowledge gaps.

Systolic Function of Right Ventricular Outflow Tract is a Better Predictor to Exercise Performance After Pulmonary Valve Replacement in Tetralogy of Fallot.

Debate on the proper timing of pulmonary valve replacement (PVR) after repair of tetralogy of Fallot is still continuing. We aim to clarify how the different components of right ventricle (RV) changed with relieved volume overload in the remodeling process after pulmonary valve replacement and gain a clear idea of the relationship between different right ventricle components function and exercise capacity after PVR in these patients. The medical records and results of cardiac magnetic resonance imaging and cardiopulmonary exercise testing of 25 consecutive eligible patients were reviewed. End-diastolic, end-systolic, and ejection fraction (EF) were determined for the total RV and its components before and after PVR. There was a marked increase in EF for the outlet after PVR (39.5±11.4 vs. 45.6±12.7, P=0.04); however, EF and volume change for the other components showed no significant difference. Peak oxygen consumption (VO2) correlated better with the RV outflow tract EF than with the EF of other components of the RV or the global EF (r=0.382, P=0.018), and the time interval between initial repair and PVR showed a significant correlation with peak VO2 (r=-0.339, P=0.037). Multivariate analysis showed the RV outflow tract EF to be the only independent predictor of exercise capacity (β=0.479; P=0.046). The systolic function of the RV outflow tract could be a reliable determinant of intrinsic RV performance in repaired TOF (rTOF) patients and a promising parameter for deciding timing of pulmonary valve replacement so as to achieve the best possible exercise capacity in repaired TOF patients.

Preoperative thresholds for mid-to-late haemodynamic and clinical outcomes after pulmonary valve replacement in tetralogy of Fallot.

The right ventricle (RV) remodels early after pulmonary valve replacement (PVR) in tetralogy of Fallot (TOF) patients. Previously reported preoperative thresholds to achieve early postoperative RV normalization were consistently close to 80 mL/m(2) for end-systolic volume (ESV) and 160 mL/m(2) for end-diastolic volume (EDV). Our objective was to determine whether these thresholds were also associated with mid-to-late RV normalization and clinical events. Out of a multicentre cohort of 157 TOF patients who had undergone PVR, in 65 patients (62% male, age 29 ± 8 years, homograft in 98%) cardiovascular magnetic resonance (CMR) imaging was performed preoperatively and >3 years (6.3 years, interquartile range: 4.9-9.5) postoperatively. Mid-to-late haemodynamic outcome was classified as: 'RV normalization' [RV ejection fraction (EF) > 48% and RV EDV < 108 mL/m(2)] in 14 of 65 (22%) patients, 'intermediate' in 34 of 65 (52%) patients, and 'suboptimal' (RV EF < 45% and RV EDV > 120 mL/m(2)) in 17 of 65 (26%) patients. Preoperative RV ESV < 80 mL/m(2) was strongly associated with favourable mid-to-late haemodynamic outcome in a proportional odds model [common odds ratio (OR): 0.04 for worse class, 95% confidence interval (CI): 0.01-0.17]. During 7.8 ± 4.0 years follow-up after PVR, adverse clinical events (death, sustained ventricular tachycardia, or heart failure) occurred in 18 of 106 (17%) patients with preoperative CMR available. Patients with preoperative RV ESV > 95 mL/m(2) were at increased risk for unfavourable mid-to-late haemodynamic outcome (common OR: 25.5, 95% CI: 5.35-122) and events (hazard ratio: 2.89, 95% CI: 1.03-8.11). In TOF patients who had undergone PVR, the best preoperative threshold to achieve mid-to-late RV normalization was RV ESV < 80 mL/m(2). Patients with preoperative RV ESV > 95 mL/m(2) were at increased risk for suboptimal haemodynamic outcome and adverse clinical events. Our findings may assist in timing of PVR.

Impact of Pulmonary Valve Replacement in Tetralogy of Fallot With Pulmonary Regurgitation: A Comparison of Intervention and Nonintervention

The timing and indicators for surgical pulmonary valve replacement (PVR) in patients with pulmonary regurgitation (PR) after repair of tetralogy of Fallot (ToF) are controversial. In this study we tested the hypothesis that delaying PVR in patients with ToF and severe PR would lead to short-term progressive deterioration in right ventricular/left ventricular (RV/LV) dimensions or function. We compared PVR-treated patients with matched untreated patients who were eligible for PVR based on hemodynamic status. A current cohort of 87 patients with ToF and free PR serial cardiovascular magnetic resonance (CMR) assessments at a median interval of 1.8 years (interquartile range [IQR], 1.4-2.1) were identified. During this interval, 51 patients had surgical PVR and 36 patients were managed conservatively. Twenty-five patients from each group were matched for comparison using propensity score matching (PSM). RV and LV measurements were assessed by CMR at rest at follow-up. There was no significant deterioration in RV or LV measurements in the matched untreated patients over a median of 1.8 years. "Normalization" of right ventricular end-diastolic volume (RVEDV) and end systolic volume (ESV) after PVR occurred in the majority of patients during the study period, and no absolute ceiling beyond which the right ventricle did not normalize could be discerned. In a group of treated patients who were not matchable because of severe baseline characteristics, there was a significant improvement in resting cardiac output (CO) after PVR (from 2.9 to 3.3 L/min/m(2); p = 0.001). Our data indicate that patients with intermediate RV dilatation and severe PR are at low risk for significant progression in the short term, which can guide the interval for CMR imaging and advise the timing for future PVR.

Internal flow fraction as a potential indicator of pulmonary valve replacement in tetralogy of Fallot patients

Background Standard of care for TOF patients is a complete surgical repair in infancy but this results in free pulmonary regurgitation as no suitable long-term substitute for the obstructive valve is available. Although chronic pulmonary regurgitation can be well tolerated for decades, many patients (>20%) eventually develop right ventricular dysfunction and often require PVR. Determining the optimal timing of PVR is difficult, and there is no clear consensus within the medical community. In TOF patients before PVR, clinical studies have demonstrated a correlation between QRS duration and RV size with negative electromechanical interaction and dyssynchrony that progresses with RV enlargement. IFF is a quantitative measure of the energy loss throughout the cardiac cycle due to dyssynchronous contraction. We have developed a means of quantifying IFF noninvasively from cardiac magnetic resonance (CMR) images. In this study, we hypothesized that IFF within the left ventricle would increase in serial CMR exams prior to PVR.

Pulmonary valve replacement in tetralogy of Fallot improves the repolarization

Pulmonary valve replacement in tetralogy of Fallot improves the repolarization

Interventional Electrophysiology in Patients With Congenital Heart Disease

“The treatment of congenital heart disease is unsatisfactory. As a rule, nothing can be done to improve patients symptomatically; in some instances digitalis may be of help.” — —L. Emmett Holt, MD, 1933 On August 26, 1938, Dr Robert Gross performed the first successful surgery for a congenital heart defect by closing a patent ductus arteriosus in a 7-year-old girl. The event marked the beginning of an interventional approach to congenital heart disease (CHD) that forever banished the sort of pessimism expressed by Dr Holt in his classic pediatric textbook only 5 years earlier.1 Subsequent diagnostic and operative innovations ultimately led to surgical solutions for nearly all anatomic heart defects, allowing the vast majority of infants born with CHD in the modern era to survive into adulthood. However, improved hemodynamic longevity has exposed alternate sources of morbidity and mortality for this population, central among which are cardiac rhythm disorders. In some instances, arrhythmias are intrinsic to the CHD lesion itself, but in most cases, they arise as an unintended consequence of prior corrective surgery whenever patches and suture lines function in conjunction with hypertrophy and fibrosis to create the substrate for reentrant tachycardias. It is fortunate that improved understanding of rhythm abnormalities in CHD has coincided with the emergence of interventional electrophysiological techniques. Catheter ablation, arrhythmia surgery, pacemakers, and implantable defibrillators have now become indispensable treatment options for this group. It is the purpose of this article to review the application of these tools to CHD with an emphasis on unique technical challenges. Congenital heart defects occur in roughly 0.8% of live births, and in 30% to 50% of cases, the malformations are severe enough to warrant ≥1 surgical procedures during early childhood.2 Arrhythmia mechanisms vary according to the underlying anatomic defect and method of surgical repair. The …

Pulmonary valve replacement in tetralogy of Fallot improves the repolarization

Objective To assess the effect of pulmonary valve replacement (PVR) on the repolarization of patients with tetralogy of Fallot. Background Pulmonary valve regurgitation may cause right ventricular failure in adult patients with Fallot's tetralogy. In these patients, prolonged depolarization and disturbed repolarization are associated with ventricular arrhythmias and sudden cardiac death. Methods Thirty Fallot patients (age 32 ± 9 years, 19 male) eligible for PVR were studied with cardiac magnetic resonance imaging (CMR) before and 6 months after PVR. Electrocardiograms obtained during initial and follow-up CMR were analyzed and occurrence of ventricular arrhythmias was studied. Results Right ventricular end-diastolic volume (RV EDV) decreased from 322 ± 87 to 215 ± 57 ml after PVR ( P < 0.0001). The spatial QRS-T angle normalized from 117 ± 34 to 100 ± 35°, P = 0.0004 (normal angle < 105°). QT dispersion and T-wave complexity did not change significantly. T-wave amplitude decreased from 376 ± 121 to 329 ± 100 μV ( P = 0.01). T-wave area decreased from 43 ± 15 to 38 ± 13 μV s ( P = 0.02). Decreases in T-wave amplitude and area were most prominent in the right precordial leads overlying the RV. Three patients had sustained ventricular arrhythmias and one patient died suddenly. These patients had a QRS duration > 160 ms. No severe ventricular arrhythmias were found in patients with a RV EDV < 220 ml, QRS-T angle < 100°, QT dispersion < 60 ms or T-wave complexity < 0.30. Conclusion Normal repolarization indices may be associated with the absence of severe ventricular arrhythmias. PVR in Fallot patients with dilated right ventricles has a beneficial effect on electrocardiographic indices of repolarization heterogeneity.

Reduction of QRS duration following pulmonary valve replacement in tetralogy of Fallot: implications for arrhythmia reduction?

This editorial refers to ‘Reduction of QRS duration after pulmonary valve replacement in adult Fallot patients is related to reduction of right ventricular volume’† by B. Hooft van Huysduynen et al. , on page 928 Tetralogy of Fallot is the commonest form of cyanotic congenital heart disease, and early outcomes following surgical repair are steadily improving. Nonetheless, these patients remain at risk for late-onset arrhythmias as well as sudden death.1,2 Increased QRS duration and right ventricular (RV) dilation secondary to pulmonary regurgitation have both been described as markers for increased risk of ventricular arrhythmias and sudden death.3–5 Pulmonary valve replacement (PVR) in these patients has been shown to stabilize the QRS duration and, when combined with cryoablation, to decrease the incidence of ventricular arrhythmias.6 Hooft van Huysduyen et al. 7 present a retrospective series of adult patients with tetralogy of Fallot, who were assessed before and … *Corresponding author. E-mail address: andrew.redington{at}sickkids.ca

Aortic valve replacement in tetralogy of Fallot and pulmonary atresia with major aortoputmonary collateral arteries

SummaryA 29-year-old woman who had tetralogy of Fallot and pulmonary atresia with major aortopulmonary collateral arteries developed aortic regurgitation due to infectious endocarditis. Isolated aortic valve replacement was undertaken because of heart failure unresponsive to medical therapy. Excessive flow through the aortopulmonary collateral arteries during cardiopulmonary bypass was controlled by means ofintraaortic balloons which were inflated to occlude the origin of the collateral arteries. Arterial return from the pump was delivered through separate cannulation of the ascending aorta and the right femoral artery. We believe that this method should be considered in those circumstances when excessive flow through systemic-to-pulmonary arteries is expected during cardiopulmonary bypass.