Computational Study on the Effects of Valve Orientation on the Hemodynamics and Leaflet Dynamics of Bioprosthetic Pulmonary Valves

Pulmonary valves do not display a fibrous annulus as do other valves in the heart; thus, pulmonary valves can be implanted at multiple orientations and locations within the right ventricular outflow tract (RVOT). This gives surgeons more freedom when implanting the valve but it also results in uncertainties regarding placement, particularly with respect to valve orientation. We investigate the pulmonary artery hemodynamics and valve leaflet dynamics of pulmonary valve replacements (PVRs) with various orientations via fluid-structure interaction (FSI) models. A canonical model of the branching pulmonary artery is coupled with a dynamic model of a pulmonary valve, and from this we quantify the effect of valve implant orientation on the postvalvular hemodynamics and leaflet dynamics. Metrics such as turbulent kinetic energy (TKE), branch pulmonary artery flow distributions, projected valve opening area (PVOA), and pressure differentials across the valve leaflets are analyzed. Our results indicate that off-axis orientation results in higher pressure forces and flow and energy asymmetry, which potentially have implications for long-term durability of implanted bioprosthetic valves.

Transcatheter Pulmonary Valve Replacement in Middle and Late Adulthood

Transcatheter pulmonary valve replacement (TPVR) is now frequently performed in patients with adult congenital heart disease. As the life expectancy of the population with adult congenital heart disease continues to improve, more patients will require pulmonary valve intervention. This study details the short-term and midterm clinical outcomes of patients aged ≥40 years who underwent TPVR. We performed an institutional retrospective cohort study that included patients aged ≥40 years who underwent TPVR (and clinical follow-up) from January 1, 2012 to January 1, 2024. Descriptive analyses, Kaplan-Meier survival analysis, and Cox proportional hazard modeling were used to determine outcomes and risk factors affecting survival. The study included 67 patients, and median age at TPVR was 48 years (43 to 57). Median hospital length of stay after TPVR was 1 day (1 to 3); periprocedural complications occurred in 5 patients, and acute kidney injury occurred in 1 patient. Median duration of follow-up was 3.5 years (0.1 to 9.7). There were 9 total deaths, and 1-, 3-, and 5-year Kaplan-Meier survival after TPVR was 95%, 91%, and 82%, respectively. Moderate or worse right ventricular dysfunction was present in 22 patients before TPVR and in 20 patients after TPVR. Inpatient status before TPVR negatively affected survival (hazard ratio 24.7, 3.3 to 186.1, p = 0.002). In conclusion, TPVR was performed in patients aged ≥40 years with favorable periprocedural and midterm follow-up outcomes including survival, but right ventricular dysfunction did not improve, and further exploration of the ideal timing of TPVR in this age group is warranted.

Radiofrequency Perforation of an Atretic Pulmonary Valve with a Modified Coronary Wire and Electrocautery Pencil

Radiofrequency (RF) perforation of an atretic pulmonary valve is commonly performed in patients with pulmonary atresia with intact ventricular septum with specifically designed RF wires. In difficult anatomy or low-resource centers, this may instead be successfully performed with a modified coronary guide wire and an electrocautery surgical pencil.

Isolated pulmonary valve endocarditis in a pediatric patient with down syndrome

BACKGROUND

Isolated pulmonary valve endocarditis (IPE) accounts for less than 2% of all infective endocarditis patients. It is commonly associated with several predisposing factors, including intravenous drug use (IVDU) and congenital heart disease. The most common causative pathogens of IPE are Staphylococcus aureus and Streptococcus viridans. We report a Down's syndrome patient with IPE and with no standard risk factors caused by the rare pathogen Acinetobacter spp. This led to respiratory failure and systemic infection due to septic pulmonary emboli. Early elective surgery was decided upon as the patient was no longer responding to medical therapy, and his clinical condition was worsening over time.

CASE PRESENTATION

A 15-year-old male with Down syndrome and no underlying heart defect presented with a 3-month history of episodic fever, nausea, vomiting, and diarrhea. Transthoracic echocardiography (TTE) revealed large vegetation on the pulmonary valve leaflet, another mobile mass at the pulmonary artery bifurcation, and severe pulmonary regurgitation. Serial blood cultures isolated Acinetobacter spp. Despite initial antibiotic therapy, the patient continued to have sepsis, unresolved vegetations, and developed life-threatening complications and respiratory distress, which convinced us to perform a pulmonary valve replacement surgery with a homograft. After surgery, the patient recovered and was discharged on the ninth postoperative day (POD).

CONCLUSION

This report highlights IPE's diagnostic and therapeutic challenges, alongside the importance of a comprehensive cardiopulmonary workup in patients with unexplained fever, sepsis, and pulmonary symptoms, even without typical risk factors. Based on the patient's aggravating condition despite medical treatment, early surgical intervention and pulmonary valve replacement were deemed crucial. However, there still needs to be a definitive guideline on when and how surgery should be performed in patients with complicated IPE, especially in pediatric patients.

Extravascular protrusion of the Alterra adaptive prestent identified on surveillance computed tomography imaging

BACKGROUND

The Alterra adaptive prestent is a novel self-expanding device designed to provide a landing zone for the 29 mm SAPIEN 3 valve to treat pulmonary regurgitation in patients with a right ventricular outflow tract that is too large for a balloon expandable valve alone. The mechanism of fixation for the Alterra prestent is radial force from the self-expanding stent frame, combined with a unique set of flared "tines" that protrude from both ends of the stent.

AIMS, METHODS, AND RESULTS

In this report, we describe 6 patients who underwent uncomplicated transcatheter pulmonary valve replacement with an Alterra adaptive prestent and SAPIEN 3 valve and had surveillance chest computed tomography (CT) scans performed 1 day to 21 months after implant. In each patient, the CT scan demonstrated extravascular extension of a portion of the Alterra prestent, without clinical sequelae, but with extension into the ascending aorta in 1 patient and contact with the ascending aorta, left pulmonary vein, or left atrial appendage in 3 others.

CONCLUSIONS

Surveillance CT imaging shows that the Alterra prestent can perforate the pulmonary artery and/or right ventricle. Although no sequelae were seen in these patients, prestent perforation has the potential to be clinically important. Implanters should be aware of this finding and its potential implications. As experience with the Alterra prestent grows, it will be important to further define the risk factors, incidence, and implications of this phenomenon.

Simultaneous Aortic and Pulmonary Valve Replacement in Repaired Congenital Heart Disease

OBJECTIVES

 Patients with congenital heart disease frequently require surgical or percutaneous interventional valve replacement after initial congenital heart defect (CHD) repair. In some of these patients, simultaneous replacement of both semilunar valves is necessary, resulting in increased procedural complexity, morbidity, and mortality. In this study, we analyze the outcomes of simultaneous aortic and pulmonary valve replacements following multiple surgical interventions for CHD.

METHODS

 This was a retrospective study of 24 patients who after initial repair of CHD underwent single-stage aortic and pulmonary valve replacement at our institution between 2003 and 2021.

RESULTS

 The mean age of the patients was 28 ± 13 years; the mean time since the last surgery was 15 ± 11 years. Decellularized valved homografts (DVHs) were used in nine patients, and mechanical valves were implanted in seven others. In eight patients, DVHs, biological, and mechanical valves were implanted in various combinations. The mean cardiopulmonary bypass time was 303 ± 104 minutes, and aortic cross-clamp time was 152 ± 73 minutes. Two patients died at 12 and 16 days postoperatively. At a maximum follow-up time of 17 years (mean 7 ± 5 years), 95% of the surviving patients were categorized as New York Heart Association heart failure class I.

CONCLUSION

 Single-stage aortic and pulmonary valve replacement after initial repair of CHD remains challenging with substantial perioperative mortality (8.3%). Nevertheless, long-term survival and clinical status at the latest follow-up were excellent. The valve type had no relevant impact on the postoperative course. The selection of the valves for implantation should take into account operation-specific factors-in particular reoperability-as well as the patients' wishes.

Differences in Right Heart Function After Pulmonary Valve Replacement in Patients With Pulmonary Valve Stenosis Versus Tetralogy of Fallot

BACKGROUND

There are limited data about the impact of timing of pulmonary valve replacement (PVR) on right heart reverse remodeling in patients with pulmonary regurgitation following intervention for isolated pulmonary valve stenosis (PS). This study compared differences in postprocedural right heart reverse remodeling after early versus late PVR (defined as PVR before versus after attainment of the conservative consensus criteria proposed by Bokma et al, 2018) in patients with prior intervention for PS, using patients with tetralogy of Fallot as the reference group.

METHOD AND RESULTS

Right atrial reservoir strain and right ventricular free wall strain was measured at baseline, 1 and 3 years after PVR. There were 114 patients with PS (early PVR, 87 [76%]; late PVR, 27 [24%]) and 291 patients with tetralogy of Fallot (early PVR, 197 [67%]; late PVR, 96 [33%]). The PS group had greater improvement in right atrial reservoir strain at 1 year (12%±4% versus 8%±4%; P<0.001) and 3 years (15%±6% versus 9%±6%; P<0.001), and a greater improvement in right ventricular free wall strain at 1 year (12%±4% versus 7%±3%, P=0.008) and 3-years (16%±6% versus 12%±5%; P=0.01) after PVR compared with the tetralogy of Fallot group. There was no difference in right heart reverse remodeling between patients who underwent early versus later PVR within the PS group. In contrast, late PVR was associated with less right heart reverse remodeling within the tetralogy of Fallot group.

CONCLUSIONS

These data suggest that patients with palliated PS presenting pulmonary regurgitation have a more benign clinical course, and hence delaying PVR in this population may be appropriate.

Left anterior mini-thoracotomy: an alternative approach for pulmonary valve replacement after surgically corrected tetralogy of fallot

INTRODUCTION

Pulmonary regurgitation (PR) remains a common sequela in patients following surgically corrected TOF, and may lead to progressive right ventricle dilatation and dysfunction. The conventional approach of redo-sternotomy for pulmonary valve replacement (PVR) is associated with increased operative time as well as risks of bleeding and injury to the heart and great vessels. Thus, left anterior mini-thoracotomy has become an alternative approach in eliminating the risks of redo-sternotomy in these patients. This series aimed to determine the outcomes of minimally invasive pulmonary valve replacement after surgical TOF correction.

METHODS

A retrospective analysis was conducted on 24 patients with severe PR post-surgical TOF correction who underwent left anterior mini-thoracotomy PVR in Penang General Hospital from January 2021 to January 2023.

RESULTS

The median age was 23.5 years (I.Q.range 17.6-36.3), with a male:female ratio of 1:4. Majority of patients had mild to moderate symptoms prior to surgery and 19 patients (79.1%) were on regular diuretics medication. All patients had severe free-flow PR with evidence of right ventricular dilatation and dysfunction. Magnetic Resonance Imaging and computed tomography of pulmonary artery were performed prior to surgery. Minimally invasive PVR was performed on all patients via left upper anterior mini-thoracotomy and femoral-femoral bypass without cardioplegic arrest. The operative time and cardiopulmonary bypass time were 208 (I.Q.range 172-324) and 98.6 minutes(I.Q.range 87.4-152.4) respectively. The time to wean off inotropes postoperatively was 6.2 hours (I.Q.range1.4-14.8), and no postoperative arrhythmia and chest re-exploration were reported. Most patients stayed in Intensive Care Unit (ICU) for 10.8 hours (I.Q.range 8.4-36.5), and the total hospital stay was 4.2 days (I.Q.range 3.4-7.6). 2 patients (11.1%) required blood transfusion postoperative. There was no paravalvular leak and no mortality during the follow-up period of up to 28 months.

CONCLUSION

Minimally invasive PVR after surgical correction of TOF is a safe alternative to the conventional redo-sternotomy approach in patients with favorable anatomy. This approach is able to reduce the risks associated with redo-sternotomy, particularly bleeding and injury to mediastinal structures, with the additional benefit of expedited recovery and hospital discharge. Our series has shown a safe and efficient approach in these patients with favorable outcomes.

The Ross-Konno Procedure With or Without Mitral Valve Surgery: A Systematic Review With Individual Data Pooling

Background: The Ross-Konno procedure is a technically demanding surgical option to treat multilevel left ventricular outflow tract obstruction. Methods: A systematic review with pooled analyses was conducted according to PRISMA criteria on studies published between January 2000 and May 2022 that assessed outcomes following the Ross-Konno intervention in children. Individual patient data were extracted from published Kaplan-Meier curves using digitalization software. Overall survival and freedom from reintervention were assessed by time-to-event approaches. Determinants of one-year survival were investigated by meta-regression analyses. Results: Ten studies with a total population of 274 patients were included. The overall pooled early (≤30 days) survival rate was 86.9% (95% CI [87.6%-78.4%]). Five-year survival rates in patients without and with (N = 50 [18.2%] of 274 total patients) concomitant mitral valve surgery were 82.5% (95% CI [87.6%-77.4%]) versus 56.1% (95% CI [74.1%-38.1%]), hazard ratio 2.67, 95% CI (1.44-4.93), P < .0001. Five- and ten-year freedom from pulmonary autograft reoperation rates were 93.5% and 90.9%, respectively. Five- and ten-year freedom from right ventricular outflow tract reoperation rates were 74.3% and 57.3%, respectively. By meta-regression analysis, resection of endocardial fibroelastosis (N = 32 [11.7%] of 274 total patients) was associated with superior one-year survival (P = .027). Conclusion: The Ross-Konno procedure is associated with substantial early mortality and gradual attrition thereafter. Mortality is higher in patients with concomitant mitral valve surgery. Resection of endocardial fibroelastosis is associated with superior survival. Right ventricular outflow tract reinterventions are common.

Comparison of Right Ventricular Outflow Tract Reconstruction Techniques on Mid-Term Pulmonic Valve Fate

Introduction: The pulmonic valve-sparing technique (PVS) is an emerging approach of right ventricular outflow tract reconstruction in tetralogy of Fallot (TOF) correction aimed at reducing the incidence of pulmonic regurgitation (PR) and the need for subsequent reintervention. This study aims to compare the long-term occurrence of moderate to severe PR/stenosis (PR/PS) between three different approaches. Patients and Methods: We conducted a retrospective cohort study involving 173 patients who underwent TOF correction at Chiang Mai University hospital between January 2006 and December 2016. The patients were divided into three groups: transannular patch (TAP; n = 88, 50.9%), monocusp insertion (MCI; n = 40, 23.1%), and PVS (n = 45, 26%). The study assessed freedom from moderate to severe PR/PS. Results: The median overall follow-up time was 79.8 months (interquartile range: 50.7-115.5 months. The PVS exhibited larger PV Z-score (-2.6 ± 2.3 mm, P < .001), with predominantly tricuspid morphology (64.4%). The PVS had significantly shorter median ventilator time, intensive care unit stay, hospital stay, and longer median follow-up time. Postoperative moderate-severe PR was lower in the PVS group (P < .001), with no significant difference in PS (P = .356) and complications among the groups. Freedom from moderate-severe PR/PS was longer in the MCI group (2.8, 0.2-42.3 months vs 30.9, 0.2-50.9 months, respectively). Multivariable analysis showed TAP and MCI had a higher risk of developing moderate-severe PR (hazard ratio [HR] 2.51; 95% confidence interval [CI] 1.23-5.13 vs HR 1.41; 95%CI 0.59-3.38) but lower risk of moderate-severe PS (HR 0.14; 95%CI 0.02-0.9 vs HR 0.39; 95%CI 0.05-3.19). Conclusion: Pulmonic valve-sparing reconstruction showed promise in preventing late moderate-severe PR in patients with favorable PV anatomy. However, it should be noted that this technique is associated with a higher incidence of PS.

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.

Long-term outcome after the Ross procedure in 173 adults with up to 25 years of follow-up

OBJECTIVES

The potential risk of autograft dilatation and homograft stenosis after the Ross procedure mandates lifelong follow-up. This retrospective cohort study aimed to determine long-term outcome of the Ross procedure, investigating autograft and homograft failure patterns leading to reintervention.

METHODS

All adults who underwent the Ross procedure between 1991 and 2018 at the University Hospitals Leuven were included, with follow-up data collected retrospectively. Autograft implantation was performed using the full root replacement technique. The primary end-point was long-term survival. Secondary end-points were survival free from any reintervention, autograft or homograft reintervention-free survival, and evolution of autograft diameter, homograft gradient and aortic regurgitation grade over time.

RESULTS

A total of 173 adult patients (66% male) with a median age of 32 years (range 18-58 years) were included. External support at both the annulus and sinotubular junction was used in 38.7% (67/173). Median follow-up duration was 11.1 years (IQR, 6.4-15.9; 2065 patient-years) with 95% follow-up completeness. There was one (0.6%) perioperative death. Kaplan-Meier estimate for 15-year survival was 91.1% and Ross-related reintervention-free survival was 75.7% (autograft: 83.5%, homograft: 85%). Regression analyses demonstrated progressive neoaortic root dilatation (0.56 mm/year) and increase in homograft gradient (0.72 mmHg/year).

CONCLUSIONS

The Ross procedure has the potential to offer excellent long-term survival and reintervention-free survival. These long-term data further confirm that the Ross procedure is a suitable option in young adults with aortic valve disease which should be considered on an individual basis.

Melody transcatheter pulmonary valve replacement: a single-center case series in Southeast Asia

BACKGROUND

Studies of transcatheter pulmonary valve replacement (TPVR) with the Melody valve have demonstrated good clinical and hemodynamic outcomes. Our study analyzes the midterm clinical and hemodynamic outcomes for patients who underwent Melody valve implantation in Southeast Asia.

METHODS

Patients with circumferential conduits or bioprosthetic valves and experiencing post-operative right ventricular outflow tract (RVOT) dysfunction were recruited for Melody TPVR.

RESULTS

Our cohort (n = 14) was evenly divided between pediatric and adult patients. The median age was 19 years (8-38 years), a male-to-female ratio of 6:1 with a median follow-up period of 48 months (16-79 months), and the smallest patient was an 8-year-old boy weighing 18 kg. All TPVR procedures were uneventful and successful with no immediate mortality or conduit rupture. The primary implant indication was combined stenosis and regurgitation. The average conduit diameter was 21 ± 2.3 mm. Concomitant pre-stenting was done in 71.4% of the patients without Melody valve stent fractures (MSFs). Implanted valve size included 22-mm (64.3%), 20-mm (14.3%), and 18-mm (21.4%). After TPVR, the mean gradient across the RVOT was significantly reduced from 41 mmHg (10-48 mmHg) to 16 mmHg (6-35 mmHg) at discharge, p < 0.01. Late follow-up infective endocarditis (IE) was diagnosed in 2 patients (14.3%). Overall freedom from IE was 86% at 79 months follow-up. Three patients (21.4%) developed progressive RVOT gradients.

CONCLUSION

For patients in Southeast Asia with RVOT dysfunction, Melody TPVR outcomes are similar to those reported for patients in the US in terms of hemodynamic and clinical improvements. A pre-stenting strategy was adopted and no MSFs were observed. Post-implantation residual stenosis and progressive stenosis of the RVOT require long term monitoring and reintervention. Lastly, IE remained a concern despite vigorous prevention and peri-procedural bacterial endocarditis prophylaxis.

Short- and Mid-Term Results of Pulmonary Valve Replacement with the Inspiris Valve

BACKGROUND

Various bioprosthetic valves are used off-label for pulmonary valve replacement (PVR), but there is no consensus on whether a particular valve is best for this application. Recently, the Inspiris Resilia valve (Edwards Lifesciences Inc) was approved for aortic valve replacement, and surgeons have begun using it for PVR. There is limited evidence on the performance of the Inspiris valve compared with other valves in the pulmonary position.

METHODS

This study reviewed all patients who underwent PVR with a size 19- to 29-mm Inspiris valve or Mosaic valve (Medtronic Inc) from 2007 to 2022 at Lucile Packard Children's Hospital Stanford (Palo Alto, CA). Midterm outcomes included freedom from moderate or severe pulmonary regurgitation (PR), a maximum Doppler gradient ≥36 mm Hg, and freedom from reintervention.

RESULTS

A total of 225 consecutive patients who underwent PVR with a size 19- to 29-mm Mosaic (n = 163) or Inspiris (n = 62) valve were included. There was no difference in baseline characteristics. Early postoperative gradients were low in both groups but higher in the Mosaic cohort, and neither group had more than mild PR on discharge. On univariable and multivariable analysis, Inspiris valves were significantly more likely to develop moderate or greater PR over time. There was no significant difference between the valves in freedom from reintervention or from a maximum gradient ≥36 mm Hg.

CONCLUSIONS

Early and short-term gradients were similar in patients undergoing PVR with Inspiris and Mosaic valves, but significant PR was more common in patients who received an Inspiris valve. These preliminary findings suggest that the durability of the Inspiris valve in the pulmonary position may not be superior to that of other bioprosthetic valves used for PVR.

First reported long-term two- and three-dimensional echocardiographic follow-up with histopathological analysis of a transcatheter pulmonary valve implantation in a pet dog

Transcatheter pulmonary valve implantation (TPVI) is indicated for use in the management of failing pulmonary valves in humans. We report here the long-term follow-up of the first documented transcatheter pulmonary valve implanted in a client-owned dog. A one-year-old Beagle dog with severe congenital type A valvular pulmonic stenosis first underwent percutaneous balloon pulmonary valvuloplasty, leading two years later to severe pulmonary regurgitation. A TPVI using a Melody™ bioprosthetic valve was then successfully performed, with normalization of the right heart cavities. Repeated two- and three-dimensional transthoracic echocardiographic examinations combined with Doppler modes confirmed the appropriate position and function of the valve for four years. Mitral myxomatous valvular degeneration led to refractory left-sided congestive heart failure, and the dog was humanely euthanized. After postmortem examination, X-ray imaging and histopathological evaluation of the stent and the valve were performed. Ex-vivo imaging of the implanted valve using a Faxitron® Path radiography system and microscopic evaluation of the implanted stent and bioprosthetic leaflets did not show any relevant leaflet or stent alterations. This case provides a proof of concept in interventional veterinary cardiology, showing that TPVI can be performed in dogs with subsequent long-term maintaining normal pulmonary valve function.