Percutaneous Pulmonary Valve Implantation Alters Electrophysiologic Substrate

PR and QRS interval changes after transcatheter pulmonary valve replacement in children

BACKGROUND

Changes in PR intervals after transcatheter pulmonary valve replacement (TCPVR) have not been thoroughly evaluated in children. This study evaluated the changes in PR and QRS intervals six months after TCPVR in children with congenital heart disease.

RESULTS

This study included 41 patients who underwent TCPVR from 2010 to 2022. ECG of patients was reviewed before and six months after TCPVR, and the PR and QRS intervals were reported. Right ventricular systolic pressure (RVSP) was retrieved indirectly from echocardiography and compared pre- and 6-months after TPVR. The median age was 13 years (25th-75th percentiles: 11-16), and 61% were males. The preoperative diagnosis was tetralogy of Fallot (n = 29, 71%), transposition of great vessels (n = 4, 10%), common arterial trunk (n = 3, 7%), pulmonary valve stenosis (n = 3, 7%) and pulmonary atresia (n = 2, 5%). The Melody valve was used in 30 patients, and Edwards Sapien was used in 11 patients. RVSP was significantly reduced six months after the procedure (pre-RVSP 40 (30-55) mmHg vs. post-RVSP 25 (20-35) mmHg; P < 0.001). The PR interval was 142 (132-174) msec before TPVR and 146 (132-168) msec post-TCPVR (P = 0.442). Post-TPVR PR was positively related to the pre-PR (β: 0.79 (0.66-0.93), P < 0.001) and inversely related to the right ventricular outflow tract size (- 1.48 (- 2.76 to - 0.21), P = 0.023). The pre-TPVR QRS was 130 (102-146) msec, and the post-TPVR QRS was 136 (106-144) msec (P = 0.668).

CONCLUSIONS

In children undergoing TCPVR, the PR and QRS intervals did not change significantly during a 6-month follow-up.

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.

Ventricular Arrhythmias and Sudden Death Following Percutaneous Pulmonary Valve Implantation in Pediatric Patients

Reports have suggested a transient increase in ventricular ectopy early after percutaneous pulmonary valve implantation (PPVI). Little is known about the potential for more serious ventricular arrhythmias (VA) in children who undergo PPVI. We sought to evaluate the incidence of severe VA following PPVI in a pediatric population and to explore potential predictive factors. A retrospective cohort study was conducted of patients who underwent PPVI under 20 years of age in our institution from January 2007 to December 2019. The primary outcome of severe VA was defined as sustained and/or hemodynamically unstable ventricular tachycardia (VT), inducible sustained VT, or sudden death of presumed arrhythmic etiology. A total of 21 patients (mean age 16.2 ± 2.1 years; 66.7% male) underwent PPVI. The majority of patients (N = 15; 71.4%) had tetralogy of Fallot (TOF) or TOF-like physiology, with the most common indication being pulmonary insufficiency (N = 10; 47.6%). During a median follow-up of 29.6 months (IQR 10.9-44.0), severe VA occurred in 3 (14.3%) patients aged 15.6 (IQR 14.7-16.1) a median of 12.3 months (IQR 11.2-22.3) after PPVI. All events occurred in patients with TOF-like physiology following Melody valve implant. In conclusion, severe VA can occur long after PPVI in a pediatric population, particularly in those with TOF-like physiology. Further studies are required to elucidate underlying mechanisms and assess strategies to mitigate risks.

Percutaneous pulmonary valve implantation (PPVI) in non-obstructive right ventricular outflow tract: limitations and mid-term outcomes

BACKGROUND

Percutaneous pulmonary valve implantation (PPVI) has been established as a safe and effective alternative to surgery treating patients with a failing pulmonary valve conduit. Nevertheless, the majority of patients in need of a valve have a native, non-obstructive right ventricular outflow tract (RVOT). The current approved stent-valves have a balloon-expandable design. Pre-stenting of the RVOT to create a landing zone and also protect the valve stability is usually mandatory; large, non-obstructive RVOTs need pre-stenting to reduce the RVOT-diameter for a balloon-expandable valve implantation.

METHODS

A retrospective study design was used to analyze the medium-term outcome after PPVI in a series of 26 patients with native or reconstructed RVOT.

RESULTS

PPVI was successfully performed in all, but 1 (96%). Within the follow-up of a minimum of 2 years, the percutaneous implanted valves remained competent; a significant pressure gradient was not detected. Furthermore, no PPVI-related complications such as endocarditis, migration or stent fractures were observed. The electrocardiogram at rest, in particular the QRS duration remained unchanged immediate post-PPVI as well as at medium-term follow-up of 24 months. However, ventricular arrhythmias were documented in 3 patients (11.5%); all patients were successfully treated with antiarrhythmic drugs, utilizing metoprolol. A trial of an invasive catheter based RVOT-ablation in one remained unsuccessful; pre-stented RVOT did not allow a successful intervention.

CONCLUSIONS

Medium-term follow-up showed excellent results of the mechanical valve function. PPVI utilizing balloon-expandable stent-valves in a native RVOT remains an off-label use. Despite our encouraging results, advanced manipulations of the patched or native RVOT might be associated with significant ventricular arrhythmias. There is a need for less invasive RVOT reduction devices.

Percutaneous pulmonary valve implantation as an alternative to repeat open-heart surgery for patients with pulmonary outflow obstruction: a reality in Singapore

Right ventricle to pulmonary artery (RV-PA) conduits have been used for the surgical repair of congenital heart defects. These conduits frequently become stenosed or develop insufficiency with time, necessitating reoperations. Percutanous pulmonary valve implantation (PPVI) can delay the need for repeated surgeries in patients with congenital heart defects and degenerated RV-PA conduits. We presented our first experience with PPVI and described in detail the procedural methods and the considerations that are needed for this intervention to be successful. Immediate and short-term clinical outcomes of our patients were reported. Good haemodynamic results were obtained, both angiographically and on echocardiography. PPVI provides an excellent alternative to repeat open-heart surgery for patients with congenital heart defects and degenerated RV-PA conduits. This represents a paradigm shift in the management of congenital heart disease, which is traditionally managed by open-heart surgery.

Ventricular arrhythmia burden after transcatheter versus surgical pulmonary valve replacement

Objective

Comparative ventricular arrhythmia (VA) outcomes following transcatheter (TC-PVR) or surgical pulmonary valve replacement (S-PVR) have not been evaluated. We sought to compare differences in VAs among patients with congenital heart disease (CHD) following TC-PVR or S-PVR.

Methods

Patients with repaired CHD who underwent TC-PVR or S-PVR at the UCLA Medical Center from 2010 to 2016 were analysed retrospectively. Patients who underwent hybrid TC-PVR or had a diagnosis of congenitally corrected transposition of the great arteries were excluded. Patients were screened for a composite of non-intraoperative VA (the primary outcome variable), defined as symptomatic/recurrent non-sustained ventricular tachycardia (VT) requiring therapy, sustained VT or ventricular fibrillation. VA epochs were classified as 0–1 month (short-term), 1–12 months (mid-term) and ≥1 year (late-term).

Results

Three hundred and two patients (TC-PVR, n=172 and S-PVR, n=130) were included. TC-PVR relative to S-PVR was associated with fewer clinically significant VAs in the first 30 days after valve implant (adjusted HR 0.20, p=0.002), but similar mid-term and late-term risks (adjusted HR 0.72, p=0.62 and adjusted HR 0.47, p=0.26, respectively). In propensity-adjusted models, S-PVR, patient age at PVR and native right ventricular outflow tract (RVOT) (vs bioprosthetic/conduit outflow tract) were independent predictors of early VA after pulmonary valve implantation (p<0.05 for all).

Conclusion

Compared with S-PVR, TC-PVR was associated with reduced short-term but comparable mid-term and late-term VA burdens. Risk factors for VA after PVR included a surgical approach, valve implantation into a native RVOT and older age at PVR.

Pediatrics Spanish Registry of Percutaneous Melody Pulmonary Valve Implantation in Patients Younger Than 18 Years

INTRODUCTION AND OBJECTIVES

A decade has passed since the first Spanish percutaneous pulmonary Melody valve implant (PPVI) in March 2007. Our objective was to analyze its results in terms of valvular function and possible mid-term follow-up complications.

METHODS

Spanish retrospective descriptive multicenter analysis of Melody PPVI in patients < 18 years from the first implant in March 2007 until January 1, 2016.

RESULTS

Nine centers were recruited with a total of 81 PPVI in 77 pediatric patients, whose median age and weight were 13.3 years (interquartile range [IQR], 9.9-15.4) and 46kg (IQR, 27-63). The predominant cardiac malformation was tetralogy of Fallot (n = 27). Most of the valves were implanted on conduits, especially bovine xenografts (n = 31). The incidence of intraprocedure and acute complications was 6% and 8%, respectively (there were no periprocedural deaths). The median follow-up time was 2.4 years (IQR, 1.1-4.9). Infective endocarditis (IE) was diagnosed in 4 patients (5.6%), of which 3 required surgical valve explant. During follow-up, the EI-related mortality rate was 1.3%. At 5 years of follow-up, 80% ± 6.9% and 83% ± 6.1% of the patients were free from reintervention and pulmonary valve replacement.

CONCLUSIONS

Melody PPVI was safe and effective in pediatric patients with good short- and mid-term follow-up hemodynamic results. The incidence of IE during follow-up was relatively low but was still the main complication.