Adverse Events, Radiation Exposure, and Reinterventions Following Transcatheter Pulmonary Valve Replacement

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.

Early Outcomes From a Multicenter Transcatheter Self-Expanding Pulmonary Valve Replacement Registry

BACKGROUND

Transcatheter pulmonary valve replacement (TPVR) with the self-expanding Harmony valve (Medtronic) is an emerging treatment for patients with native or surgically repaired right ventricular outflow tract (RVOT) pulmonary regurgitation (PR). Limited data are available since U.S. Food and Drug Administration approval in 2021.

OBJECTIVES

In this study, the authors sought to evaluate the safety and short-term effectiveness of self-expanding TPVR in a real-world experience.

METHODS

This was a multicenter registry study of consecutive patients with native RVOT PR who underwent TPVR through April 30, 2022, at 11 U.S.

CENTERS

The primary outcome was a composite of hemodynamic dysfunction (PR greater than mild and RVOT mean gradient >30 mm Hg) and RVOT reintervention.

RESULTS

A total of 243 patients underwent TPVR at a median age of 31 years (Q1-Q3: 19-45 years). Cardiac diagnoses were tetralogy of Fallot (71%), valvular pulmonary stenosis (21%), and other (8%). Acute technical success was achieved in all but 1 case. Procedural serious adverse events occurred in 4% of cases, with no device embolization or death. Hospital length of stay was 1 day in 86% of patients. Ventricular arrhythmia prompting treatment occurred in 19% of cases. At a median follow-up of 13 months (Q1-Q3: 8-19 months), 98% of patients had acceptable hemodynamic function. Estimated freedom from the composite clinical outcome was 99% at 1 year and 96% at 2 years. Freedom from TPVR-related endocarditis was 98% at 1 year. Five patients died from COVID-19 (n = 1), unknown causes (n = 2), and bloodstream infection (n = 2).

CONCLUSIONS

In this large multicenter real-world experience, short-term clinical and hemodynamic outcomes of self-expanding TPVR therapy were excellent. Ongoing follow-up of this cohort will provide important insights into long-term outcomes.

Aspirin Responsiveness in a Cohort of Pediatric Patients with Right Ventricle to Pulmonary Artery Conduits and Transcatheter Valve Replacement Systems

The aim of this study was to determine the rate of aspirin responsiveness in a cohort of pediatric patients with in situ xenograft valved right ventricle to pulmonary artery (RV-PA) conduits and/or transcatheter valve replacements (TVR). Aspirin is routinely prescribed to these patients. Optimizing anti-platelet therapy could promote valve longevity and reduce the risk of infective endocarditis in this at-risk group. This was a prospective, observational study. Patients were recruited from both ward and outpatient settings. Patients were eligible if under 18 years and taking aspirin. Non-response to aspirin was defined as > 20% platelet aggregation using light transmission platelet aggregometry (LTA) and < 50% platelet inhibition by thromboelastography with platelet mapping (TEGPM). Participants were invited to provide a confirmatory sample in cases of aspirin resistance and dose adjustments were made. Thirty patients participated. Median age was 9 years (2 months to 18 years). The majority (93%) had complex right ventricular outflow tract pathology. 13 (43%) had an RV-PA conduit and 24 (80%) had a TVR, with valve situated in conduit in 7 (23%) cases. Rate of aspirin non-response on initial testing was 23% (n = 7/30) with median LTA 74.55% (60-76%) and TEG 13.25% (0-44%) in non-responders. Non-responders were more likely to be under 1 year. Two patients required dose increases and one patient non-adherence to dose was identified. Four patients on repeat testing were responsive to aspirin by laboratory tests. The rate of aspirin non-response on laboratory testing in this cohort of patients was 23% and resulted in therapeutic intervention in 10%.

Safety and Short-Term Outcomes for Infants < 2.5 kg Undergoing PDA Device Closure: A C3PO Registry Study

To evaluate short-term procedural outcomes and safety for infants < 2.5 kg who underwent catheterization with intended patent ductus arteriosus (PDA) device closure in a multi-center registry, as performance of this procedure becomes widespread. A multi-center retrospective review was performed using data from the Congenital Cardiac Catheterization Project on Outcomes (C3PO) registry. Data were collected for all intended cases of PDA closure in infants < 2.5 kg from April 2019 to December 2020 at 13 participating sites. Successful device closure was defined as device placement at the conclusion of the catheterization. Procedural outcomes and adverse events (AE) were described, and associations between patient characteristics, procedural outcomes and AEs were analyzed. During the study period, 300 cases were performed with a median weight of 1.0 kg (range 0.7-2.4). Successful device closure was achieved in 98.7% of cases with a 1.7% incidence of level 4/5 AEs, including one periprocedural mortality. Neither failed device placement nor adverse events were significantly associated with patient age, weight or institutional volume. Higher incidence of adverse events associated with patients who had non-cardiac problems (p = 0.017) and cases with multiple devices attempted (p = 0.064). Transcatheter PDA closure in small infants can be performed with excellent short-term outcomes and safety across institutions with variable case volume.

Long-term outcomes of transcatheter pulmonary valve implantation with melody and SAPIEN valves

BACKGROUND

Transcatheter pulmonary valve implantation (TPVI) is effective for treating right ventricle outflow tract (RVOT) dysfunction. Factors associated with long-term valve durability remain to be investigated.

METHODS

Consecutive patients successfully treated by TPVI with Melody valves (n = 32) and SAPIEN valves (n = 182) between 2008 and 2020 at a single tertiary centre were included prospectively and monitored.

RESULTS

The 214 patients had a median age of 28 years (range, 10-81). The RVOT was a patched native pulmonary artery in 96 (44.8%) patients. Median follow-up was 2.8 years (range, 3 months-11.4 years). Secondary pulmonary valve replacement (sPVR) was performed in 23 cases (10.7%), due to stenosis (n = 22, 95.7%) or severe regurgitation (n = 1, 4.3%), yielding an incidence of 7.6/100 patient-years with melody valves and 1.3/100 patient-years with SAPIEN valves (P = 0.06). The 5- and 10-year sPVR-freedom rates were 78.1% and 50.4% with Melody vs. 94.3% and 82.2% with SAPIEN, respectively (P = 0.06). The incidence of infective endocarditis (IE) was 5.5/100 patient-years with Melody and 0.2/100 patient-years with SAPIEN (P < 0.0001). Factors associated with sPVR by univariate analysis were RV obstruction before TPVI (P = 0.04), transpulmonary maximal velocity > 2.7 m/s after TPVI (p = 0.0005), valve diameter ≤ 22 mm (P < 0.003), IE (P < 0.0001), and age < 25 years at TPVI (P = 0.04). By multivariate analysis adjusted for IE occurrence, transpulmonary maximal velocity remained associated with sPVR.

CONCLUSIONS

TPVI is effective for treating RVOT dysfunction. Incidence of sPVR is higher in patients with residual RV obstruction or IE. IE add a substantial risk of TPVI graft failure and is mainly linked to the Melody valve.

SOCIAL MEDIA ABSTRACT

Transcatheter pulmonary valve implantation is effective for treating right ventricular outflow tract dysfunction in patients with congenital heart diseases. Incidence of secondary valve replacement is higher in patients with residual obstruction or infective endocarditis.

Ventricular arrhythmias following transcatheter pulmonary valve replacement with the harmony TPV25 device

BACKGROUND

Transcatheter pulmonary valve replacement (TPVR) with the Harmony valve (Medtronic, Inc.) was recently approved to treat postoperative native outflow tract pulmonary regurgitation. While the 22 mm Harmony valve Early Feasibility Study demonstrated ventricular tachycardia (VT) in only 5% of patients, little is known about ventricular arrhythmias after TPVR with the larger 25 mm valve (TPV25).

METHODS

A single center review was performed of patients with TPV25 implant from 2020 to 2021. Demographic, cardiac, procedural, and postimplant cardiac telemetry data were collected and compared between patients who did and did not have peri-implant ventricular arrhythmia.

RESULTS

Thirty patients underwent TPV25 at a median age of 30 years. On postimplant telemetry, VT events were documented in 12 patients (40%); 11 nonsustained VT (NSVT) (median 3 episodes per patient and 6 beats per episode, maximum 157 episodes) and 1 sustained VT (3%), with Torsades de Pointes secondary to a short coupled premature ventricular contraction (PVC). VT events were associated with annular valve positioning (p &lt; 0.001) and increased postimplant PVC burden (p &lt; 0.0001), but there was no association between VT and other demongraphic, historical, or procedural factors. The frequency of NSVT events fell from 3/h from 0 to 12 h postimplant to 0.5/hr from 12 to 24 h (p &lt; 0.001).

CONCLUSION

VT occurred commonly (40%) in the first 24 h after TPV25 implant, with self-limited NSVT in 11 of 12 patients and 1 patient with cardiac arrest secondary to Torsades de Pointes. VT only occurred with annular valve positioning. Larger, longer-term studies are needed to determine risk factors for and natural history of post-TPVR VT.

Pre- and Postprocedure Imaging of Transcatheter Pulmonary Valve Implantation

Transcatheter pulmonary valve replacement (TPVR) is a minimally invasive procedure for treatment of right ventricular outflow tract (RVOT) dysfunction in surgically repaired congenital heart diseases. TPVR is performed in these patients to avoid the high risk and complexity of repeat surgeries. Several TPVR devices are now available to be placed in the right ventricle (RV) to pulmonary artery (PA) conduit, native RVOT, or surgical bioprosthetic valves. Imaging is used before TPVR to determine patient eligibility and optimal timing, which is critical to avoid irreversible RV dilatation and failure. Imaging is also required for evaluation of contraindications, particularly proximity of the RVOT to the left main coronary artery and its branches. Cross-sectional imaging provides details of the complex anatomy in which the TPVR device will be positioned and measurements of the RVOT, RV-PA conduit, or PA. Echocardiography is the first-line imaging modality for evaluation of the RVOT or conduit to determine the need for intervention, although its utility is limited by the complex RVOT morphology and altered anatomy after surgery. CT and MRI provide complementary information for TPVR, including patient eligibility, assessment of contraindications, and key measurements of the RVOT and PA, which are necessary for procedure planning. TPVR, performed using a cardiac catheterization procedure, includes a sizing step in which a balloon is expanded in the RVOT, which also allows assessment of the risk for extrinsic coronary artery compression. Follow-up imaging with CT and MRI is used for evaluation of postprocedure remodeling and valve function and to monitor complications. ^©RSNA, 2022 Online supplemental material is available for this article.

Echocardiographic Assessment of Melody Versus Sapien Valves Following Transcatheter Pulmonary Valve Replacement

OBJECTIVES

The aim of this study was to compare the immediate and midterm echocardiographic performance of the Melody (Medtronic Inc) and Sapien (Edwards Lifesciences Inc) valves after transcatheter pulmonary valve replacement (TPVR) in native and conduit right ventricular outflow tracts (RVOTs).

BACKGROUND

TPVR is now a common procedure, but limited data exist comparing postimplantation echocardiographic findings between Melody and Sapien valves.

METHODS

This was a single-institution retrospective cohort study of all patients who underwent successful TPVR from 2011 to 2020. Patient demographics, procedural details, and immediate and midterm echocardiographic findings were collected and compared between valve types using the Wilcoxon rank sum, chi-square, or Fisher exact test as appropriate. Subgroups were analyzed individually and were adjusted for multiple comparisons using the Bonferroni method.

RESULTS

A total of 328 patients underwent successful TPVR (Melody: n = 202, Sapien: n = 126). The groups had a similar baseline age, weight, and diagnosis. The most common indications for TPVR were pulmonary stenosis (32.2%) or mixed disease (46%) in the Melody group and pulmonary insufficiency in the Sapien group (52.4%) (P < 0.001). Sapien valves were more often placed in native RVOTs (43.7% vs 18.8%; P < 0.001). The discharge and follow-up mean and peak Doppler gradients were similar between the Melody and Sapien groups. Valves implanted in native RVOTs had significantly lower postimplantation gradients at each follow-up period.

CONCLUSIONS

Echocardiographic performance after TPVR was generally acceptable and similar when comparing Melody and Sapien valves despite differences in the indication and anatomy in each group. The peak and mean gradients were lower in transcatheter valves implanted in native RVOTs compared with those implanted in conduits or bioprosthetic valves.

Reintervention and Survival After Transcatheter Pulmonary Valve Replacement

BACKGROUND

Transcatheter pulmonary valve (TPV) replacement (TPVR) has become the standard therapy for postoperative pulmonary outflow tract dysfunction in patients with a prosthetic conduit/valve, but there is limited information about risk factors for death or reintervention after this procedure.

OBJECTIVES

This study sought to evaluate mid- and long-term outcomes after TPVR in a large multicenter cohort.

METHODS

International registry focused on time-related outcomes after TPVR.

RESULTS

Investigators submitted data for 2,476 patients who underwent TPVR and were followed up for 8,475 patient-years. A total of 95 patients died after TPVR, most commonly from heart failure (n = 24). The cumulative incidence of death was 8.9% (95% CI: 6.9%-11.5%) 8 years after TPVR. On multivariable analysis, age at TPVR (HR: 1.04 per year; 95% CI: 1.03-1.06 per year; P < 0.001), a prosthetic valve in other positions (HR: 2.1; 95% CI: 1.2-3.7; P = 0.014), and an existing transvenous pacemaker/implantable cardioverter-defibrillator (HR: 2.1; 95% CI: 1.3-3.4; P = 0.004) were associated with death. A total of 258 patients underwent TPV reintervention. At 8 years, the cumulative incidence of any TPV reintervention was 25.1% (95% CI: 21.8%-28.5%) and of surgical TPV reintervention was 14.4% (95% CI: 11.9%-17.2%). Risk factors for surgical reintervention included age (0.95 per year [95% CI: 0.93-0.97 per year]; P < 0.001), prior endocarditis (2.5 [95% CI: 1.4-4.3]; P = 0.001), TPVR into a stented bioprosthetic valve (1.7 [95% CI: 1.2-2.5]; P = 0.007), and postimplant gradient (1.4 per 10 mm Hg [95% CI: 1.2-1.7 per 10 mm Hg]: P < 0.001).

CONCLUSIONS

These findings support the conclusion that survival and freedom from reintervention or surgery after TPVR are generally comparable to outcomes of surgical conduit/valve replacement across a wide age range.

Procedural Risk in Congenital Cardiac Catheterization (PREDIC3T)

Background

Advancements in the field, including novel procedures and multiple interventions, require an updated approach to accurately assess patient risk. This study aims to modernize patient hemodynamic and procedural risk classification through the creation of risk assessment tools to be used in congenital cardiac catheterization.

Methods and Results

Data were collected for all cases performed at sites participating in the C3PO (Congenital Cardiac Catheterization Project on Outcomes) multicenter registry. Between January 2014 and December 2017, 23 119 cases were recorded in 13 participating institutions, of which 88% of patients were <18 years of age and 25% <1 year of age; a high‐severity adverse event occurred in 1193 (5.2%). Case types were defined by procedure(s) performed and grouped on the basis of association with the outcome, high‐severity adverse event. Thirty‐four unique case types were determined and stratified into 6 risk categories. Six hemodynamic indicator variables were empirically assessed, and a novel hemodynamic vulnerability score was determined by the frequency of high‐severity adverse events. In a multivariable model, case‐type risk category (odds ratios for category: 0=0.46, 1=1.00, 2=1.40, 3=2.68, 4=3.64, and 5=5.25; all P≤0.005) and hemodynamic vulnerability score (odds ratio for score: 0=1.00, 1=1.27, 2=1.89, and ≥3=2.03; all P≤0.006) remained independent predictors of patient risk.

Conclusions

These case‐type risk categories and the weighted hemodynamic vulnerability score both serve as independent predictors of patient risk for high‐severity adverse events. This contemporary procedure‐type risk metric and weighted hemodynamic vulnerability score will improve our understanding of patient and procedural outcomes.

Novel Minimal Radiation Approach for Percutaneous Pulmonary Valve Implantation

The aim of the study is to evaluate the impact of multimodality imaging technology during percutaneous pulmonary valve implantation (PPVI). Among percutaneous procedures, PPVI traditionally has one of the highest patient radiation exposures. Different protocol modifications have been implemented to address this problem (i.e., improvements in guidance systems, delivery systems, valve design, post-implantation evaluation). Although the effectiveness of individual modifications has been proven, the effect of an approach which combines these changes has not been reported. We performed a retrospective chart review of 76 patients who underwent PPVI between January 2018 and December 2019. Patients were classified in "Traditional protocol," using routine biplane angiography and/or 3D rotational angiography (3DRA); and "Multimodality protocol" that included the use of VesselNavigator for guidance, selective 3DRA for coronary evaluation, Long DrySeal Sheath for valve delivery, and Intracardiac Echocardiography for valve evaluation after implantation. Radiation metrics, procedural time, and clinical outcomes were compared between groups. When the traditional protocol group was compared with the multimodality protocol group, a significant reduction was described for total fluoroscopy time (31.6 min vs. 26.2 min), dose of contrast per kilogram (1.8 mL/Kg vs. 0.9 mL/Kg), DAP/kg (26.6 µGy·m²/kg vs. 19.9 µGy·m²/kg), and Air Kerma (194 mGy vs. 99.9 mGy). A reduction for procedure time was noted (140 min vs. 116.5 min), but this was not statistically significant. There was no difference in clinical outcomes or the presence of complications between groups. The combination of novel technology in PPVI caused a significant reduction in radiation metrics without increasing the complication rate in our population.

Comparison of Management Strategies for Neonates With Symptomatic Tetralogy of Fallot

BACKGROUND

Neonates with tetralogy of Fallot and symptomatic cyanosis (sTOF) require early intervention.

OBJECTIVES

This study sought to perform a balanced multicenter comparison of staged repair (SR) (initial palliation [IP] and subsequent complete repair [CR]) versus primary repair (PR) treatment strategies.

METHODS

Consecutive neonates with sTOF who underwent IP or PR at ≤30 days of age from 2005 to 2017 were retrospectively reviewed from the Congenital Cardiac Research Collaborative. The primary outcome was death. Secondary outcomes included component (IP, CR, PR) and cumulative (SR): hospital and intensive care unit lengths of stay; durations of cardiopulmonary bypass, anesthesia, ventilation, and inotrope use; and complication and reintervention rates. Outcomes were compared using propensity score adjustment.

RESULTS

The cohort consisted of 342 patients who underwent SR (IP: surgical, n = 256; transcatheter, n = 86) and 230 patients who underwent PR. Pre-procedural ventilation, prematurity, DiGeorge syndrome, and pulmonary atresia were more common in the SR group (p ≤0.01). The observed risk of death was not different between the groups (10.2% vs 7.4%; p = 0.25) at median 4.3 years. After adjustment, the hazard of death remained similar between groups (hazard ratio: 0.82; 95% confidence interval: 0.49 to 1.38; p = 0.456), but it favored SR during early follow-up (<4 months; p = 0.041). Secondary outcomes favored the SR group in component analysis, whereas they largely favored PR in cumulative analysis. Reintervention risk was higher in the SR group (p = 0.002).

CONCLUSIONS

In this multicenter comparison of SR or PR for management of neonates with sTOF, adjusted for patient-related factors, early mortality and neonatal morbidity were lower in the SR group, but cumulative morbidity and reinterventions favored the PR group, findings suggesting potential benefits to each strategy.

The Safety and Efficacy of Transcatheter Pulmonary Valve Replacement Combined with Electrophysiology Procedures

The objective of this study was to evaluate the safety and efficacy of combining transcatheter pulmonary valve replacement (TPVR) and electrophysiology (EP) procedures. A retrospective review was undertaken to identify TPVR and EP procedures that were concomitantly performed in the cardiac catheterization laboratory at University of Iowa Stead Family Children's Hospital from January 2011 to October 2019. Procedural and follow-up data were compared between patients who underwent TPVR and EP procedures in the same setting to those who received TPVR or EP procedure separately and that were similar in age and cardiac anatomy. A total of 8 patients underwent combined TPVR and EP procedures. One patient was excluded due to lack of adequate control, leaving seven study subjects (57% female; median age at time of procedure 16 years). The median follow-up time was 11.5 months (range 2-36 months). Patients who received combined TPVR and EP had shorter recovery times (combined: median 18.9 h; IQR 18.35-19.5 vs separate: median 27.98 h; IQR 21.42-39.25; p-value 0.031), shorter hospital length of stay (combined: median 27.5 h; IQR 26.47-31.4 vs separate: median 38.4 h; IQR 33.42-51.50; p-value 0.016), and a 51% reduction in total hospital charges (combined: median $171,640; IQR 135.43-219.22 vs separate: median $333,560 IQR 263.20-400.98; p-value 0.016). There were no significant differences in radiation dose or procedure time between the combined and control groups. The median radiation time for those who had the combination procedure was 30.5 min [IQR 29.6-47.9], and the median dose area product was 215 mGy [IQR 158-935]. In conclusion, combining TPVR and EP procedures is feasible, safe, and economically advantageous.

Four right ventricle to pulmonary artery conduit types

OBJECTIVE

The most durable valved right ventricle to pulmonary artery conduit for the repair of congenital heart defects in patients of different ages, sizes, and anatomic substrate remains uncertain.

METHODS

We performed a retrospective analysis of 4 common right ventricle to pulmonary artery conduits used in a single institution over 30 years, using univariable and multivariable models of time-to-failure to analyse freedom from conduit dysfunction, reintervention, and replacement.

RESULTS

Between 1988 and 2018, 959 right ventricle to pulmonary artery conduits were implanted: 333 aortic homografts, 227 pulmonary homografts, 227 composite porcine valve conduits, and 172 bovine jugular vein conduits. Patients weighed 1.6 to 98.3 kg (median 15.3 kg), and median duration of follow-up was 11.4 years, with 505 (52.2%) conduits developing dysfunction, 165 (17.2%) requiring catheter intervention, and 415 (43.2%) being replaced. Greater patient weight, conduit z-score, type and position, as well as catheter intervention were predictors of freedom from replacement. Multivariable analysis demonstrated inferior durability for smaller composite porcine valve conduits, with excellent durability for larger diameter conduits of the same type. Bovine jugular vein conduit longevity was inferior to that of homografts in all but the smallest patients. Freedom from dysfunction at 8 years was 60.7% for aortic homografts, 72% for pulmonary homografts, 51.2% for composite porcine valve conduits, and 41.3% for bovine jugular vein conduits. Judicious oversizing of the conduit improved conduit durability in all patients, but to the greatest extent in patients weighing 5 to 20 kg.

CONCLUSIONS

Pulmonary and aortic homografts had greater durability than xenograft conduits, particularly in patients weighing 5 to 20 kg. Judicious oversizing was the most significant surgeon-modifiable factor affecting conduit longevity.

Early Outcomes of Percutaneous Pulmonary Valve Implantation with Pulsta and Melody Valves: The First Report from Korea

Percutaneous pulmonary valve implantation (PPVI) is used to treat pulmonary stenosis (PS) or pulmonary regurgitation (PR). We described our experience with PPVI, specifically valve-in-valve transcatheter pulmonary valve replacement using the Melody valve and novel self-expandable systems using the Pulsta valve. We reviewed data from 42 patients undergoing PPVI. Twenty-nine patients had Melody valves in mostly bioprosthetic valves, valved conduits, and homografts in the pulmonary position. Following Melody valve implantation, the peak right ventricle-to-pulmonary artery gradient decreased from 51.3 ± 11.5 to 16.7 ± 3.3 mmHg and right ventricular systolic pressure fell from 70.0 ± 16.8 to 41.3 ± 17.8 mmHg. Thirteen patients with native right ventricular outflow tract (RVOT) lesions and homograft underwent PPVI with the new self-expandable Pulsta valve—a nitinol wire stent mounted with a trileaflet porcine pericardial valve. Following Pulsta valve implantation, cardiac magnetic resonance imaging showed a decreased PR fraction and that the right ventricular end-diastolic volume index decreased from 166.1 ± 11.9 to 123.6 ± 12.4 mL/m². There were no mortality, severe procedural morbidity, or valve-related complications. At the mean 14.2 month (4–57 months) follow-up, no patients had more than mild PR. PPVI using Melody and Pulsta valves was first shown to provide excellent early outcomes without serious adverse event in most patients with RVOT dysfunction in Korea.