Transcatheter Pulmonary Valve in Congenital Heart Disease.

Over the last 2 decades, experience with transcatheter pulmonary valve replacement (TPVR) has grown significantly and has become an effective and reliable way of treating pulmonary valve regurgitation, right ventricular outflow (RVOT) obstruction, and dysfunctional bioprosthetic valves and conduits. With the introduction of self-expanding valves and prestents, dilated native RVOT can be addressed with the transcatheter approach. In this article, the authors review the current practices, technical challenges, and outcomes of TPVR.

Flow pattern analysis of right ventricular outflow tract in repaired tetralogy of Fallot through 4D flow MRI.

Cardiac magnetic resonance imaging (CMR) often shows discrepancies between right ventricular outflow tract (RVOT) flow and left ventricular outflow tract flow in patients with late-stage repaired tetralogy of Fallot (rTOF), leading to potential errors in pulmonary regurgitation fraction (PRF) assessment. This study aimed to identify the conditions under which RVOT flow can be acutely evaluated using four-dimensional (4D) flow CMR. Twenty-seven consecutive patients with rTOF underwent both two-dimensional phase-contrast (2D PC) and 4D flow CMR between 2016 and 2018, excluding those with peripheral pulmonary artery stenosis, RVOT conduit replacement, unknown surgical method, and an aortic valve regurgitation greater than 20%. Seven healthy controls also underwent only 4D Flow CMR. All healthy controls and fifteen patients with rTOF showed laminar RVOT flow, while seven patients exhibited helical, and four patients exhibited vortical RVOT flow in 4D flow CMR visualization. Flow-volume concordance between the pulmonary artery and aortic flow was significantly lower in patients with rTOF and PRF > 40% in 2D PC CMR. This concordance rate in the suprapulmonary valve was high in both the TOF and control groups, comparing at five RVOT locations in 4D flow CMR. Regarding RVOT flow regurgitation in 4D flow, the whole bulk evaluation exhibited greater variation depending on the flow type compared to the whole pixel-wise evaluation. The study confirmed the flow volume at the upper section of the pulmonary valve as the most accurate correlate of aortic flow volume. Furthermore, the 4D flow CMR using the pixel-wise method demonstrated superior accuracy compared to the traditional bulk flow method.

Electromechanical Dyssynchrony Is Associated With Right Ventricular Remodeling and Dysfunction Independently of Pulmonary Regurgitation Late After Tetralogy of Fallot Repair.

BACKGROUND: The aim of this study was to investigate the relationship among right ventricular (RV) dilatation, dysfunction, and electromechanical dyssynchrony (EMD) in patients with repaired tetralogy of Fallot (rTOF). METHODS: Data from a prospective rTOF registry of subjects with moderate or greater pulmonary regurgitation (PR) and contemporary imaging were analyzed. Electrocardiograms and echocardiograms were analyzed for EMD (prolonged QRS duration [QRSd], echocardiographic septal flash, and mechanical delay) and mechanical dispersion. The relationship among these, RV measurements on cardiac magnetic resonance, exercise capacity, and incident arrhythmia or death was analyzed with adjustment for PR. RESULTS: In total, 271 patients with rTOF (42% women; median age, 32 years; interquartile range [IQR], 23-34 years) were included. Patients had moderate to severe PR (median PR fraction, 38%; IQR, 30%-47%), moderate to severe RV enlargement (median RV end-diastolic volume index, 161 mL/m2; IQR, 138-186 mL/m2) and mild RV systolic dysfunction (median RV ejection fraction [RVEF], 44%; IQR, 38%-48%). Eleven patients (4%) experienced ventricular arrhythmia or death. Presence of EMD was associated with larger RV size (RV end-diastolic volume index and RV end-systolic volume index, P = .006 and P < .001, respectively) and lower RVEF (P < .001). A sharp inflection in the relation among QRSd, RV size, and RVEF was observed when QRSd exceeded 150 msec (3.1% decrease in RVEF for every 20-msec increase in QRSd between 160 and 200 msec). Similar inflection points were observed for the mechanical delay between the RV basal-lateral and midseptal segments. The mechanical delay was higher in patients with vs without incident atrial arrhythmia (371 vs 276 msec, P = .014). CONCLUSIONS: In adults with rTOF, EMD is independently associated with larger RV size, lower RVEF, and incident atrial arrhythmias.

Self-Expanding Pulmonary Valves in 53 Patients With Native Repaired Right Ventricular Outflow Tracts.

BACKGROUND: Self-expanding pulmonary valve grafts have been designed for percutaneous pulmonary valve implantation (PPVI) in patients with native repaired right ventricular (RV) outflow tracts (RVOTs). However, their efficacy, in terms of RV function and graft remodelling remain unclear. METHODS: Patients with native RVOTs who received Venus P-valve (N = 15) or Pulsta valve (N = 38) implants between 2017 and 2022 were enrolled. We collected data on patient characteristics and cardiac catheterization parameters as well as imaging and laboratory data before, immediately after, and 6 to 12 months after PPVI and identified risk factors for RV dysfunction. RESULTS: Valve implantation was successful in 98.1% of patients. The median duration of follow-up was 27.5 months. In the first 6 months after PPVI, all patients exhibited resolution of paradoxical septal motion and a significant reduction (P < 0.05) in RV volume, N-terminal pro-B-type natriuretic peptide levels, and valve eccentricity indices (-3.9%). Normalization of the RV ejection fraction (≥ 50%) was detected in only 9 patients (17.3%) and was independently associated with the RV end-diastolic volume index before PPVI (P = 0.03). Nine patients had residual or recurrent pulmonary regurgitation or paravalvular leak (graded as ≥ mild), which was associated with a larger eccentricity index (> 8%) and subsided by 12 months postimplantation. CONCLUSIONS: We identified the risk factors likely to be associated with RV dysfunction and pulmonary regurgitation following PPVI in patients with native repaired RVOTs. RV volume-based patient selection is recommended for PPVI of a self-expanding pulmonary valve, along with monitoring of graft geometry.

High Variability of Right Ventricular Volumes and Function in Adults with Severe Pulmonary Regurgitation Late After Tetralogy of Fallot Repair.

Our aim was to assess changes of right ventricular end-diastolic volumes (RVEDVi) and right ventricular ejection fraction (RVEF) in asymptomatic adults with repaired tetralogy of Fallot, with native right ventricular outflow tract and severe pulmonary regurgitation by serial cardiac magnetic resonance imaging (CMR). The study included 23 asymptomatic adults who underwent ≥3 CMR studies (total of 88 CMR studies). We compared changes in RVEDVi and RVEF between first and last study (median follow-up: 8.8 years, interquartile range: 6.3 to 13.1 years) and between all study pairs. Variability of measurements between study pairs (65 consecutive and 139 nonconsecutive CMR study pairs) were assessed using Bland-Altman analysis and intraclass correlation coefficients. On average, there were no significant changes of RVEDVi or RVEF over the study period (change in RVEDVi: +0.4 ± 17.8 ml/m2, change in RVEF: -1.0 ± 5.5%). Assessment of variability of measurements between study pairs demonstrated no systematic change in RVEDVi and RVEF between study pairs with limits of agreement within the range of previously published studies (RVEDVi -29.1 to +27.2 ml/m2; RVEF -11.5% to 10.2%). High intraclass correlation coefficients for RVEDVi (0.943, 95% CI 0.906 to 0.965, p <0.001) and RVEF (0.815, 95% CI 0.697 to 0.887, p <0.0001) indicate high reliability of reported measurements. In conclusion, in asymptomatic adults with repaired tetralogy of Fallot with native right ventricular outflow tracts and severe pulmonary regurgitation, CMR measurements of RV volumes and RVEF remain stable during follow-up with variability between CMR studies in individual patients, as expected for interobserver and interstudy variability. Measurements derived from a single CMR study or changes occurring between 2 CMR studies should be used with caution for clinical decision-making.

Early Failure of a Bioprosthetic Valve in the Pulmonary Position Causing Panic.

An asymptomatic 26-year-old woman with repaired tetralogy of Fallot and a bioprosthetic pulmonary valve presented with a large thrombosis occluding most of her right ventricular outflow tract and main pulmonary arteries. Our pulmonary embolism response team was emergently consulted, resulting in considerable discussion regarding the treatment modality given the large size and high-risk nature of the thrombosis. Ultimately, she was started on a heparin infusion until she could undergo open thrombectomy and pulmonary valve repeat replacement. The patient's asymptomatic presentation, despite the considerable clot burden, complicated our approach to management but ultimately led to a measured and timely intervention.

Biomechanical Modeling to Inform Pulmonary Valve Replacement in Tetralogy of Fallot Patients After Complete Repair.

BACKGROUND: A biomechanical model of the heart can be used to incorporate multiple data sources (electrocardiography, imaging, invasive hemodynamics). The purpose of this study was to use this approach in a cohort of patients with tetralogy of Fallot after complete repair (rTOF) to assess comparative influences of residual right ventricular outflow tract obstruction (RVOTO) and pulmonary regurgitation on ventricular health. METHODS: Twenty patients with rTOF who underwent percutaneous pulmonary valve replacement (PVR) and cardiovascular magnetic resonance imaging were included in this retrospective study. Biomechanical models specific to individual patient and physiology (before and after PVR) were created and used to estimate the RV myocardial contractility. The ability of models to capture post-PVR changes of right ventricular (RV) end-diastolic volume (EDV) and effective flow in the pulmonary artery (Qeff) was also compared with expected values. RESULTS: RV contractility before PVR (mean 66 ± 16 kPa, mean ± standard deviation) was increased in patients with rTOF compared with normal RV (38-48 kPa) (P < 0.05). The contractility decreased significantly in all patients after PVR (P < 0.05). Patients with predominantly RVOTO demonstrated greater reduction in contractility (median decrease 35%) after PVR than those with predominant pulmonary regurgitation (median decrease 11%). The model simulated post-PVR decreased EDV for the majority and suggested an increase of Qeff-both in line with published data. CONCLUSIONS: This study used a biomechanical model to synthesize multiple clinical inputs and give an insight into RV health. Individualized modeling allows us to predict the RV response to PVR. Initial data suggest that residual RVOTO imposes greater ventricular work than isolated pulmonary regurgitation.

Coronary compression testing by balloon interrogation during pulmonary valve implantation: room for doubt?

OBJECTIVE: To evaluate the reliability of balloon coronary compression testing during percutaneous pulmonary valve implantation. BACKGROUND: Despite the widespread use of the 'balloon coronary test' as the preferable method to rule out the risk of coronary compression, this adverse event has been described after pulmonary valve implantation where coronary balloon test suggested no risk or low risk, calling into question the accuracy of the test. METHODS: We performed a retrospective chart review of 84 patients who underwent pulmonary valve implantation between January 2018 and December 2019 and selected 36 patients whose archived imaging was suitable to perform quantitative analysis of the 'balloon coronary test'. We focused on the spatial disparity between the right ventricular outflow tract position defined by the inflated testing balloon and the eventual implanted valve position, to classify the test as inaccurate or accurate. RESULTS: In total, 36.1% of cases were classified as having an inaccurate coronary balloon test. Among the baseline characteristics, right ventricular outflow tract substrate was identified as a significant predictor of test accuracy. Related to this characteristic, the type of testing balloon used and the size of the eventually implanted valve were found to be associated with test accuracy. CONCLUSIONS: Based on our findings, balloon coronary testing is not an accurate method of predicting final valve position with respect to fixed structures in the thorax. This may translate to a high false positive rate for the likelihood of coronary compression in pulmonary valve implantation.

Late Explantation of Venus P-Valve After Implantation: Macroscopic and Histologic Findings.

Percutaneous pulmonary valve replacement with the self-expandable Venus P-valve (Venus Medtech, Hangzhou, China) has shown satisfactory feasibility and early and midterm outcomes. However, the long-term results are not well described. This is a report of the gross and microscopic findings of an explanted Venus P-valve 78 months after implantation.

Degenerative Pulmonary Valve Insufficiency in a Patient With a Prior Bentall Procedure.

Adult pulmonary valve regurgitation most commonly presents after congenital cardiac surgery, with limited reports of pure degenerative valvular disease. We present a patient who underwent a Bentall procedure for annuloaortic ectasia with severe aortic insufficiency 14 years prior now presenting with degenerative, severe, symptomatic pulmonary valve regurgitation and normal pulmonary pressures. The patient underwent successful valve replacement with a bovine prosthesis. Recovery was unremarkable, and he continues to do well without further cardiac surgical requirements.

Outcomes in Young Adults With Tetralogy of Fallot and Pulmonary Annular Preserving or Transannular Patch Repairs.

BACKGROUND: Early surgical tetralogy of Fallot (ToF) repair involved patching across the pulmonic annulus (transannular patch [TAP] repair), which resulted in severe pulmonic regurgitation. Long-term outcome improvements were anticipated with modifications that preserved the pulmonic annulus (annulus-preserving [AP] repair). The objective of the present study was to evaluate the need for late reintervention in adults with AP repair and those with TAP repair. METHODS: We conducted a retrospective review of adults (born 1981-1996) with childhood intracardiac ToF repairs at a tertiary care center. The primary cardiovascular outcome was need for reintervention after primary intracardiac repair of ToF. Secondary outcomes included a composite of death, heart failure, and ventricular arrhythmias. RESULTS: Two hundred thirty adults were included: 104 with AP repair and 126 with TAP repair. The median age at last follow up was 25 years (interquartile range [IQR] 20-28) and the median follow-up duration was 7.9 years (IQR 3.5-12). Reintervention of any type was significantly more common in the TAP group during both childhood and adulthood (72.2% TAP vs 20.2% AP, HR 5.5, 95% CI 3.4-9.0; P < 0.001). Pulmonary valve replacement (PVR) was almost 6 times more likely in adults with TAP repair (65.1% TAP vs 16.3% AP, HR 5.7, 95% CI 3.4-9.7; P < 0.001). CONCLUSIONS: Patients who had AP ToF repair had significantly fewer late reinterventions compared with TAP repair, with the majority of reinterventions due to PVR. More long-term follow-up is required.

CT and MRI for Repaired Complex Adult Congenital Heart Diseases.

An increasing number of adult congenital heart disease (ACHD) patients continue to require life-long diagnostic imaging surveillance using cardiac CT and MRI. These patients typically exhibit a large spectrum of unique anatomical and functional changes resulting from either single- or multi-stage palliation and surgical correction. Radiologists involved in the diagnostic task of monitoring treatment effects and detecting potential complications should be familiar with common cardiac CT and MRI findings observed in patients with repaired complex ACHD. This review article highlights the contemporary role of CT and MRI in three commonly encountered repaired ACHD: repaired tetralogy of Fallot, transposition of the great arteries after arterial switch operation, and functional single ventricle after Fontan operation.

"The Heart Sound Quintet": A Case Report of Right-Sided Heart Failure Due to Free Pulmonary Regurgitation Long After Intracardiac Repair of Tetralogy of Fallot.

BACKGROUND Intracardiac repair of tetralogy of Fallot (TOF) is generally performed during childhood. However, the majority of patients develop the sequelae long after surgical repair, which results in significant right ventricular (RV) dilation, RV myocardial dysfunction, and, ultimately, in right-sided heart failure. CASE REPORT A 52-year-old man was referred to our institution for the evaluation of sudden-onset ventricular tachycardia. His medical history included RV outflow tract reconstruction at 5 years of age. Auscultation revealed a harsh diastolic regurgitant murmur, widely split first heart sound (S1), and a single second heart sound (S2), indicating a severely dilated RV due to severe pulmonary regurgitation (PR) and the presence of a non-functioning pulmonary valve. Moreover, the right-sided third heart sound (S3) and fourth heart sound (S4) were present, consistent with elevated RV filling pressure and the presence of a non-compliant RV. Eventually, the aforementioned "heart sound quintet" was confirmed using multimodal evaluation as right-sided heart failure with a concomitant severely dilated RV because of complete regression of the pulmonary valve and resultant free PR. CONCLUSIONS We encountered a case with a "heart sound quintet" that was composed of a widely split S1, single S2 with a harsh diastolic regurgitant murmur, and right-sided S3 and S4 The logical interpretation of the findings from physical examination will contribute to understanding the pathophysiology and aid clinical decision-making.

Influence of Pulmonary Valve Function Preservation Technique for Tetralogy of Fallot Repair on Right Ventricular Performance in Children.

BACKGROUND: Right ventricular (RV) ejection fraction may remain normal or even high despite significant impairment of RV myocardial performance in cases of total repair for tetralogy of Fallot (TOF). The aim of this study is to evaluate the influence of pulmonary valve function preservation (PVFP) versus monocuspid transannular patch augmentation (MTAPA) surgical strategies for Fallot repair on postoperative RV performance. METHODS: This retrospective study enrolled all patients (N = 480) who had TOF repaired at our center over a period of 7 years (March 2012 to January 2019). Group I included 377 patients (78.5%) who underwent TOF repair with MTAPA, and group II included 103 patients (21.5%) who underwent TOF repair with PVFP, which included all patients with pulmonary valve sparing with limited sub- or supravalvular patch. Patients' preoperative and postoperative echocardiography and other parameters (ventilation time, intensive care unit [ICU] stay duration, and RV myocardial performance index [RVMPI]) were recorded to evaluate RV function. RESULTS: We observed a significant statistical difference in the postoperative course between groups I and II, with excellent midterm outcomes for group II. A remarkable significant improvement of RVMPI took place in group II versus group I (P < .0001), as well as a significant decline in pulmonary regurgitation progression (P < .0001). The immediate postoperative RVMPI in group I (0.79 ± 0.63) versus that in group II (0.36 ± 0.17) was significantly higher (P < .0001), as was the late postoperative RVMPI (group I, 0.64 ± 0.25; group II, 0.49 ± 0.17; P < 0001). The postoperative RV outflow tract was decreased in group II versus group I. Group II had a significantly shorter duration on mechanical ventilation and in the ICU and less need for inotropes. CONCLUSION: We conclude that TOF repair patients have excellent RV myocardial performance with the PVFP surgical strategy in comparison with MTAPA.

Pulmonary Valve Replacement via Left Thoracotomy as an Alternative to Resternotomy.

Most patients with repaired tetralogy of Fallot (TOF) survive to adulthood and suffer from residual right ventricular pathology, mostly pulmonary regurgitation. Pulmonary valve replacement (PVR) is a procedure of choice to alleviate right ventricular dilatation and pulmonary regurgitation. Resternotomy is the standard approach for PVR in patients who have undergone TOF repair. However, these patients require multiple reoperations during their lifetime. We performed minimally invasive redo PVR through left mini-thoratocomy in 2 patients who had previously undergone TOF repair through sternotomy.

Multicenter Comparison of Percutaneous and Surgical Pulmonary Valve Replacement in Large RVOT.

BACKGROUND: A percutaneous approach for pulmonary valve replacement (PVR) is a feasible alternative to surgical PVR in selected patients with severe pulmonary regurgitation after repair of tetralogy of Fallot. However, large right ventricular outflow tract (diameter ≥ 25 mm) remains challenging. METHODS: This retrospective multicenter study enrolled consecutive patients with large right ventricular outflow tract who underwent percutaneous PVR (Venus P-valve, Venus MedTech Inc, Hangzhou, China) (n = 35) or surgical PVR (homograft valve; n = 30) between May 2014 and April 2017. Patients were followed up at 1, 3, 6, and 12 months, and yearly thereafter. Main study outcomes were pulmonary valve function and right ventricular function at discharge and midterm follow-up. RESULTS: PVR was successful in all patients. Percutaneous compared with surgical PVR group had: similarly distributed baseline characteristics; shorter hospitalization, intensive care unit stay, and endotracheal intubation duration; lower cost; lower pulmonary valve gradient before discharge; lower pulmonary valve regurgitant grade (mean difference, -0.63; 95% CI -1.11 to -0.20, P = .022), pulmonary valve gradient (mean difference, -5.7 mm Hg; 95% CI -9.4 to -2.2 mm Hg, P = .005), and right ventricular end-diastolic volume index (mean difference, -9.5 mL/m2; 95% CI -16.9 to -3.1 mL/m2, P = .022); and greater right ventricular ejection fraction (mean difference, 5.4%; 95% CI 2.4%-8.3%, P = .002) at median 36 months follow-up, without deaths in either group. CONCLUSIONS: Percutaneous PVR using Venus P-valve appeared to be a safe, efficacious and minimally invasive alternative to surgical PVR in selected patients with large right ventricular outflow tract yielding better right ventricular and pulmonary valve function at midterm follow-up.

Pulmonary Valve Function Late After Ross Procedure in 443 Adult Patients.

BACKGROUND: Limited data exist on long-term pulmonary valve function after the Ross procedure. This study sought to determine the long-term function of the pulmonary valve in 443 consecutive adult patients who underwent a Ross procedure. METHODS: All 443 patients who underwent a Ross procedure between November 1992 and March 2018 were reviewed retrospectively. All underwent pulmonary valve replacement using a cryopreserved pulmonary allograft. Freedom from the study's outcomes were calculated using Kaplan Meier survival. Risk factors for valve failure were analyzed using Cox regression. RESULTS: Mean age at time of operation was 39 years (range: 15-66 years). There was 1 (0.2%, 1 of 443) operative mortality. Nine patients required reintervention on the pulmonary allograft at a mean 6.1 years (range: 1-12 years) after Ross procedure. Patients required pulmonary allograft reintervention for infective endocarditis (n = 4), severe pulmonary stenosis (n = 4), or severe pulmonary regurgitation (n = 1). Freedom from pulmonary allograft reintervention was 98.9% (95% confidence interval [CI] 97.1%-99.6%), 97.7% (95% CI 95.1%-98.9%), 96.6% (95% CI 93.3%-98.3%), and 96.6% (95% CI 93.3%-98.3%) at 5, 10, 15, and 20 years, respectively. Freedom from pulmonary allograft dysfunction (at least moderate pulmonary regurgitation and/or mean systolic gradient ≥ 25 mm Hg and/or reintervention) was 94.5% (95% CI 91.6%-96.4%), 88.1% (95% CI 83.6%-91.4%), 84.9% (95% CI 79.6%-88.9%), and 78.3% (95% CI 69.5%-84.9%) at 5, 10, 15, and 20 years, respectively. No risk factors were identified to influence pulmonary valve durability. CONCLUSIONS: The pulmonary valve allograft gives excellent long-term function when used in adults undergoing the Ross procedure. Reintervention on the pulmonary valve is rare and significant pulmonary allograft dysfunction is uncommon.

Melody Transcatheter Pulmonary Valve Placement in a HeartMate II Patient.

Transcatheter pulmonary valve placement is emerging as a standard therapy for dysfunctional right ventricular outflow tract conduits. The Melody transcatheter pulmonary valve is indicated for use in the management of pediatric and adult patients with right ventricular outflow tract conduits measuring at least 16 mm in diameter. This is the first reported case of placement in a patient with a left ventricular assist device. We outline the preprocedural evaluation process, the procedural methods, and the outcomes of a successful implantation in a complex patient. With a team-based approach including thoughtful preprocedural evaluation, and close monitoring, successful deployment of a transcatheter pulmonary valve is possible in complex patients in the setting of mechanical circulatory support.