Right ventricular remodelling after transcatheter pulmonary valve implantation

Percutaneous pulmonary valve implantation in children and adults with an age and gender-specific analysis

BACKGROUND

There are limited studies with medium-term follow-up following percutaneous pulmonary valve implantation and no studies with a gender-specific analysis.

AIMS

To report clinical outcomes up to five years following percutaneous pulmonary valve implantation using the two most common balloon expandable valves in a mixed population of paediatric and adult patients with an age and gender-specific analysis.

METHODS

This was a single-centre retrospective observation study. Relevant data were obtained retrospectively from the case files. Age and gender- specific analysis was performed using SPSS.

RESULTS

Totally, 58 patients (13 children, 45 adults) underwent percutaneous pulmonary valve implantation. Statistically significant reduction in median right ventricular outflow tract flow velocity following valve implantation was maintained for the whole five years in adults but not in children. There were no gender-specific differences despite the study being adequately powered. Independent of valve type used, there was significant reduction of the right ventricular outflow tract flow velocity in the immediate post valve implantation period (Edwards P = 0.001, Melody P = 0.013). There was a significant negative correlation between implanted valve Z-score and subsequent right ventricular outflow tract gradient during the first two years following valve implantation.

CONCLUSION

Gender does not significantly affect valve function following percutaneous pulmonary valve implantation. It is important to consider patients' age and body surface area in relation to existing right ventricular outflow tract size during decisions for percutaneous pulmonary valve implantation.

Application of Speckle Tracking Echocardiography for Evaluating Ventricular Function after Transcatheter Pulmonary Valve Replacement

Pulmonary regurgitation usually leads to right heart dilatation and eventually right heart dysfunction, which is associated with a poor prognosis. Transcatheter pulmonary valve replacement is a developing treatment for pulmonary valve dysfunction that can take the place of traditional surgery and make up for the shortcomings of a large injury. Echocardiography plays a significant role in assessing ventricular function; however, conventional echocardiographic parameters have several limitations. Speckle tracking echocardiography has been regarded as a more accurate tool for quantifying cardiac function than conventional echocardiography. Therefore, the aim of this review was to summarize the application of speckle tracking echocardiography for evaluating right and left ventricular functions in patients after transcatheter pulmonary valve replacement.

First experience with real-time magnetic resonance imaging-based investigation of respiratory influence on cardiac function in pediatric congenital heart disease patients with chronic right ventricular volume overload

BACKGROUND

Congenital heart disease (CHD) is often associated with chronic right ventricular (RV) volume overload. Real-time magnetic resonance imaging (MRI) enables the analysis of cardiac function during free breathing.

OBJECTIVE

To evaluate the influence of respiration in pediatric patients with CHD and chronic RV volume overload.

METHODS AND MATERIALS

RV volume overload patients (n=6) and controls (n=6) were recruited for cardiac real-time MRI at 1.5 tesla during free breathing. Breathing curves from regions of interest reflecting the position of the diaphragm served for binning images in four different tidal volume classes, each in inspiration and expiration. Tidal volumes were estimated from these curves by data previously obtained by magnetic resonance-compatible spirometry. Ventricular volumes indexed to body surface area and Frank-Starling relationships referenced to the typical tidal volume indexed to body height (TTVi) were compared.

RESULTS

Indexed RV end-diastolic volume (RV-EDVi) and indexed RV stroke volume (RV-SVi) increased during inspiration (RV-EDVi/TTVi: RV load: + 16 ± 4%; controls: + 22 ± 13%; RV-SVi/TTVi: RV load: + 21 ± 6%; controls: + 35 ± 17%; non-significant for comparison). The increase in RV ejection fraction during inspiration was significantly lower in RV load patients (RV load: + 1.1 ± 2.2%; controls: + 6.1 ± 1.5%; P=0.01). The Frank-Starling relationship of the RV provided a significantly reduced slope estimate in RV load patients (inspiration: RV load: 0.75 ± 0.11; controls: 0.92 ± 0.02; P=0.02).

CONCLUSION

In pediatric patients with CHD and chronic RV volume overload, cardiac real-time MRI during free breathing in combination with respiratory-based binning indicates an impaired Frank-Starling relationship of the RV.

Reversal of Right Ventricular Remodeling After Correction of Pulmonary Regurgitation in Tetralogy of Fallot

In the sheep model with pathophysiologic changes similar to patients with repaired TOF, severe PR leads to fibrotic changes in the RV. Pulmonary valve replacement reverses these fibrotic changes. Early valve replacement led to a quick RV recovery, and in time there was no difference in outcome between early and late valve replacement. These data support the benefit of valve replacement for RV function and suggest that there is a margin in the timing of the surgery. The fibrotic changes correlated well with the circulating biomarker PICP, which can have an added value in the clinical follow-up of patients with repaired TOF.

The challenges of an aging tetralogy of Fallot population

Introduction: Advancements in surgery and management have resulted in a growing population of aging adults with tetralogy of Fallot (TOF). As a result, there has been a parallel growth in late complications associated with the sequelae from the underlying cardiac anomalies as well as the surgical and other interventional treatments.Areas covered: Here, we review challenges related to an aging population of patients with TOF, particularly late complications, and highlight advances in management and key areas for future research. Pulmonary regurgitation, heart failure, arrhythmias, and aortic complications are some of these late complications. There is also a growing incidence of acquired cardiovascular disease, obesity, and diabetes associated with aging. Management of these late complications and acquired comorbidities continues to evolve as research provides insights into long-term outcomes from medical therapies and surgical interventions.Expert opinion: The management of an aging TOF population will continue to transform with advances in imaging technologies to identify subclinical disease and valve replacement technologies that will prevent and mitigate disease progression. In the coming years, we speculate that there will be more data to support the use of novel heart failure therapies in TOF and consensus guidelines on the management of refractory arrhythmias and aortic complications.

Physiologic effects and functional outcome after treatment of dysfunctional right ventricular outflow tract in congenital heart disease using a two-stage intervention

BACKGROUND

Pathophysiological differences in relief of pulmonary stenosis (PS) as opposed to pulmonary regurgitation (PR) by percutaneous pulmonary valve implantation (PPVI) remain elusive, but might impact current assessment of procedural success and ultimately indications.

METHODS

Invasive pressure measurements, cardiac magnetic resonance imaging and cardiopulmonary exercise testing were performed before pre-stenting (BMS), after BMS and after PPVI in patients with either PS or PR.

RESULTS

In PS (n = 14), BMS reduced the right ventricular (RV) to systemic pressure ratio (0.8 ± 0.2 vs. 0.4 ± 0.1%; p < .01), improved RF EF (53 ± 14 vs. 59 ± 12%; p = .01) but introduced free PR (PR fraction post 39 ± 12%; p < .01) with no changes in effective RV stroke volume (SV). PPVI eliminated PR (PR fraction 5 ± 3%; p < .01) and improved effective RV SV (p < .01) with no changes in RV EF (p = .47). Peak VO2 improved significantly after BMS, with no changes following PPVI (26 ± 9 vs. 30 ± 11 vs. 31 ± 10 ml/kg*min). In PR (n = 14), BMS exaggerated PR (PR fraction post 47 ± 10) with reduction in effective RV SV (pre 43 ± 9 vs. post 38 ± 8 ml/m²; p = .01), which improved after PPVI (post PPVI 49 ± 9 ml/m²; p < .01), secondary to elimination of PR (PR fraction 5 ± 4%; p < .01). RV EF (pre 53 ± 11 vs. post 53 ± 9 vs. post PPVI 50 ± 9%) and Peak VO2 (pre 22 ± 7 vs. post 21 ± 7 vs. post PPVI 23 ± 7 ml/kg*min) remained unchanged.

CONCLUSIONS

Exercise capacity in patients with right ventricular outflow tract dysfunction is primarily afterload-dependent.

Percutaneous Pulmonary Valve Implantation

Percutaneous pulmonary valve implantation (PPVI) is recognized as a feasible and low risk alternative to surgery to treat dysfunctional right ventricular outflow tract (RVOT) in usually pluri-operated patients. Evolving technology allowed to develop different kind of prosthesis and to go from an initial treatment exclusively of stenotic conduit to an actual approach extended also to wide native RVOT. The Melody transcatheter pulmonary valve (TPV) and the Edwards Sapien valve are nowadays the most commonly implanted prostheses. However, other devices have been developed to treat large RVOT (i.e., the Venus p-valve, the Medtronic Harmony TPV, the Alterra Adaptive Prestent, and the Pulsta valve). Indications for PPVI are the same as for surgical interventions on pulmonary valve, with limits related to the maximum diameter of the available percutaneous prosthesis. Therefore, an accurate preoperative evaluation is of paramount importance to select patients who could benefit from this procedure. The overall periprocedural mortality incidence is around 1.4%, while freedom from RVOT reintervention ranges from 100% at 4 months to 70% at 70 months, according to the different published studies.

Percutaneous Pulmonary Valve Implantation: Current Status and Future Perspectives

Patients with congenital heart disease (CHD) with right ventricle outflow tract (RVOT) dysfunction need sequential pulmonary valve replacements throughout their life in the majority of cases. Since their introduction in 2000, the number of percutaneous pulmonary valve implantations (PPVI) has grown and reached over 10,000 procedures worldwide. Overall, PPVI has been proven safe and effective, but some anatomical variations can limit procedural success. This review discusses the current status and future perspectives of the procedure.

Percutaneous pulmonary valve implantation in patients with right ventricular outflow tract dysfunction: a systematic review and meta-analysis

Background:

Pulmonary valve replacement is required for patients with right ventricular outflow tract (RVOT) dysfunction. Surgical and percutaneous pulmonary valve replacement are the treatment options. Percutaneous pulmonary valve implantation (PPVI) provides a less-invasive therapy for patients. The aim of this study was to evaluate the effectiveness and safety of PPVI and the optimal time for implantation.

Methods:

We searched PubMed, EMBASE, Clinical Trial, and Google Scholar databases covering the period until May 2018. The primary effectiveness endpoint was the mean RVOT gradient; the secondary endpoints were the pulmonary regurgitation fraction, left and right ventricular end-diastolic and systolic volume indexes, and left ventricular ejection fraction. The safety endpoints were the complication rates.

Results:

A total of 20 studies with 1246 participants enrolled were conducted. The RVOT gradient decreased significantly [weighted mean difference (WMD) = −19.63 mmHg; 95% confidence interval (CI): −21.15, −18.11; p < 0.001]. The right ventricular end-diastolic volume index (RVEDVi) was improved (WMD = −17.59 ml/m²; 95% CI: −20.93, −14.24; p < 0.001), but patients with a preoperative RVEDVi >140 ml/m² did not reach the normal size. Pulmonary regurgitation fraction (PRF) was notably decreased (WMD = −26.27%, 95% CI: −34.29, −18.25; p < 0.001). The procedure success rate was 99% (95% CI: 98–99), with a stent fracture rate of 5% (95% CI: 4–6), the pooled infective endocarditis rate was 2% (95% CI: 1–4), and the incidence of reintervention was 5% (95% CI: 4–6).

Conclusions:

In patients with RVOT dysfunction, PPVI can relieve right ventricular remodeling, improving hemodynamic and clinical outcomes.

Percutaneous pulmonary valve implantation in grown-up congenital heart disease patients: Insights from the Zurich experience

OBJECTIVES

The aim of the study was to assess indications, procedural success, complications, echocardiographic, and clinical outcomes of percutaneous pulmonary valve implantation (PPVI) in adult patients with congenital heart disease (CHD).

BACKGROUND

PPVI offers a non-surgical treatment option for failing prosthetic conduits in pulmonary position. However, efficacy and clinical outcomes after PPVI are still underreported.

METHODS

From January 2008 to March 2016, 25 adult CHD patients with right ventricular outflow tract (RVOT) stenosis and/or pulmonary regurgitation underwent PPVI in our institution. Clinical and echocardiographic data was collected at baseline, at 12 months of follow-up and yearly afterwards.

RESULTS

Tetralogy of Fallot and repaired pulmonary atresia were among the most prevalent underlying congenital defects. Twenty-one (84%) received a Medtronic Melody® and four (16%) patients an Edwards Sapien valve prosthesis. The PPVI procedure was successful in all 25 patients. Pre-stenting was performed in all but two (8%) patients. PPVI reduced peak-to-peak pulmonary valve gradient from 43 (IQR 28-60) mmHg to 16 (IQR 14-22) mmHg (P < 0.001). Periprocedural complications occurred in two (8%) patients (tricuspid valve damage, pulmonary artery perforation). Over a median follow-up of 43 (IQR 18-58) months all patients were alive. Only two (8%) required re-operation and two (8%) developed stent fractures (one of them had not undergone pre-stenting). NYHA functional class improved significantly, with 20 (80%) patients in NYHA class I on follow-up.

CONCLUSIONS

PPVI with Medtronic Melody or Edwards Sapien valve conduits is safe and provides effective relief from right ventricular outflow tract obstruction or pulmonary regurgitation.