The Creation of an Interatrial Right-To-Left Shunt in Patients with Severe, Irreversible Pulmonary Hypertension: Rationale, Devices, Outcomes

Implantation of atrial flow regulator devices in patients with congenital heart disease and children with severe pulmonary hypertension or cardiomyopathy-an international multicenter case series

Background

The Occlutech Atrial Flow Regulator (AFR) is a self-expandable double-disc nitinol device with a central fenestration. Its use has been approved in the adult population with heart failure and described for pulmonary hypertension (PH). Only case reports and small series have been published about its use in the paediatric population and for congenital heart disease (CHD).

Objectives

The authors sought to investigate the feasibility, safety, and short-term follow-up of AFR implantation in patients with CHD or children with PH or cardiomyopathy.

Methods

This is a multicenter retrospective study involving 10 centers worldwide. Patients of any age with CHD or patients aged < 18 years with PH or cardiomyopathy needing AFR implantation were included.

Results

A total of 40 patients underwent AFR implantation. The median age of the population at the time of the procedure was 58.5 months (IQR: 31.5-142.5) and the median weight was 17 kg (IQR: 10-46). A total of 26 (65.0%) patients had CHD, nine (22.5%) children, a cardiomyopathy, and five (12.5%), a structurally normal heart. The implantation success rate was 100%. There were two early and one late device thrombosis. Two patients (5.0%) with dilated cardiomyopathy on extracorporeal membrane oxygenator (ECMO) died during the hospital stay. At a median follow-up of 330 days (IQR: 125-593), 37 (92.5%) patients were alive. At follow-up, 20 patients improved their New York Heart Association (NYHA) class, 12 patients did not change their NYHA class, and one patient with idiopathic PH worsened.

Conclusions

AFR implantation in patients with CHD and children with severe PH or cardiomyopathy is promising and seems to have beneficial effects at short-term follow-up.

Case report: Beneficial long-term effect of the atrial-flow-regulator device in a pediatric patient with idiopathic pulmonary arterial hypertension and recurring syncope

We report the long-term effect after successfully implanting an 8 mm Atrial-flow-regulator (AFR) device in a 7-year-old girl with idiopathic pulmonary hypertension with persistent syncope under triple therapy with significant improvement after implantation and absence of any further syncope. Early Implantation of the AFR device (Occlutech, Germany) can be efficient and safe interventional therapy option for pulmonary arterial hypertension with a history of syncope.

Update on Transcatheter Device Closure of Congenital Septal Defects

PURPOSE OF REVIEW

The goal of this paper is to review currently available devices for closure of atrial septal defects (ASDs) and ventricular septal defects (VSDs).

RECENT FINDINGS

Favorable results from the ASSURED trial resulted in FDA approval for the most recently developed device for transcatheter ASD closure in the United States. Further studies are required to assist in the development or approval of safe devices for transcatheter perimembranous VSD closure in pediatric patients. Device closure is the less invasive and preferred management option for many ASDs, with multiple studies demonstrating lower complication rates, shorter hospital stays, and lower mortality than surgical repair. Complex ASDs that make device closure more difficult include large defects, rim deficiencies, fenestrated defects, multiple defects, and the presence of pulmonary arterial hypertension. Device closure has also become an accepted alternative to surgery for some types of ventricular septal defects VSDs, though challenges and limitations remain. Future innovations including novel devices and techniques are needed to further expand on the types of defects that can be safely closed via transcatheter approach.

Case report: Paracorporeal lung assist device for 215 days as a bridge-to-lung transplantation in a patient with bronchopulmonary dysplasia and severe pulmonary hypertension

Pulmonary hypertension (PH) is a known and life limiting complication of preterm born young adults with bronchopulmonary dysplasia (BPD), ultimately leading to progressive right ventricular (RV) failure. Prognosis remains poor, especially in patients unresponsive to modern vasoactive pharmacotherapy. Therefore, lung transplantation presents the treatment of choice to avert cardiac failure. With limited donor organ availability and long waiting times, the implantation of a paracorporeal lung assist device (PLAD) is a way to bridge the patient as an alternative to veno-arterial ECMO. Herein, we present the case of a prematurely born 23-year-old female, who developed severe PH due to BPD and consequently experienced therapy refractory RV failure. Urgent PLAD implantation was performed and the patient successfully underwent double-lung transplantation after 215 days of PLAD support. No major PLAD-associated complications occurred and full recovery of RV function could be observed after double-lung transplantation.

Epidemiology and management of right ventricular-predominant heart failure and shock in the cardiac intensive care unit

Cardiogenic shock from left ventricular failure is a common presentation in the intensive care unit. In contrast, right ventricular (RV)-predominant heart failure (HF) causing shock is less well recognized. We review the epidemiology and mechanisms of RV-predominant HF and discuss pharmacologic and device-based approaches for the management of this challenging clinical problem.

Clinical study on the treatment of chronic heart failure with a novel D-shant atrium shunt device

BACKGROUND

Atrial septal shunt devices might improve hospitalizations and also prognosis in heart failure with increased pulmonary pressures due to left heart diseases. In recent years, atrial shunt devices have been used for the treatment of chronic heart failure, but there remains a lack of clinical experience. This study aimed to analyse the therapeutic effect of a novel type of atrial shunt on chronic heart failure.

METHODS AND RESULTS

From May 2020 to September 2020, six patients who were diagnosed with chronic heart failure and completed percutaneous D-shant atrium shunt device implantation in the Department of Cardiovascular Surgery, Union Hospital, were retrospectively included. The shunt location was evaluated by echocardiography and digital subtraction angiography. Heart function was evaluated by New York Heart Association functional class. Echocardiography was used to measure the diameter of the new chamber and ventricle, and to evaluate the degree of mitral and tricuspid regurgitation. Before operation and 6 months after operation, left atrial end-diastolic volume, right atrial end-diastolic volume, left ventricular end-diastolic volume, and right ventricular end-diastolic volume were measured by magnetic resonance imaging. Left ventricular ejection fractions and right ventricular ejection fractions were calculated. Haemodynamic indexes of right heart catheterization and clinical cardiac function indexes were collected and compared before and 6 months after shunt implantation. All six patients completed percutaneous shunt device implantation. Echocardiography and digital subtraction angiography showed that the shunt device was correctly positioned and unobstructed in all patients. Echocardiography revealed that the left ventricular diameter decreased significantly from 6.40 ± 0.57 mm to 5.03 ± 0.73 mm (P < 0.05). There was an obvious decrease in mitral regurgitation. Magnetic resonance imaging showed a reduction in the volume of the left ventricle (182.00 ± 27.02 mL vs. 125.75 ± 16.11 mL, P < 0.05). Cardiac catheter examination showed the mean left atrium pressure or pulmonary capillary wedge pressure decreased postoperatively (31.83 ± 11.55 vs. 18.00 ± 5.51 mmHg, P < 0.05). There was also obvious improvement in clinical indicators of cardiac function at 6 months after implantation.

CONCLUSIONS

This novel D-shant atrium shunt device revealed maintained good function, no dislodgement and no paradoxical emboli. After implantation, functional mitral regurgitation in all patients with heart failure with reduced ejection fraction improved.

Does patent foramen ovale presence procure favourable outcomes in patients with severe rheumatic mitral stenosis?

Mitral stenosis (MS) is tolerated for an extended period in patients with atrial septal defect (ASD) known as Lutembacher syndrome due to depressurizing effect. In a similar way, patients with patent foramen ovale (PFO) may have clinical benefits in severe MS. We aim to evaluate the clinical effects of PFO in rheumatic MS. Transthoracic and transesophageal echocardiography records of the patients with symptomatic severe MS were screened for the period between 2008 and 2019 in a single center. 320 symptomatic patients with severe MS were included and presence of PFO recorded. Left atrial appendix (LAA) thrombotic status was defined as clear, spontaneous echo contrast, and thrombus. Two different statistical models were used to determine the predictors of either smallest (mitral valve area) MVA at symptomatic presentation or more thrombogenic LAA. 34 patients had PFO. Multivariable ordinary least square model demonstrated that increase in systolic pulmonary arterial pressure, ejection fraction and presence of PFO were associated with smaller MVA on presentation. Multivariable proportional odds logistic regression model demonstrated that advanced age, increased left atrial diameter, absence of PFO were associated with more thrombotic status whereas larger MVA was associated with decreased thrombotic status in LAA. Presence of PFO in severe MS results in two clinical benefits as (i) being asymptomatic with smaller MVA and (ii) having less LAA thrombosis probably caused by depressurizing effect on the left atrial pressure. Our study could serve as an example for patient groups with expected symptomatic benefits from left atrium pressure offloading interventions.

Atrial flow regulator for drug-resistant pulmonary hypertension in a young child

This case describes the successful implantation of an Occlutech Atrial Flow Regulator in a young child with idiopathic pulmonary hypertension and recurrent syncope despite targeted combination therapy, with subsequent relief of symptoms.

One-year results of the first-in-man study investigating the Atrial Flow Regulator for left atrial shunting in symptomatic heart failure patients: the PRELIEVE study

AIMS

Attenuating exercise-induced elevated left atrial pressure with an atrial shunt device is under clinical investigation for treatment of symptomatic heart failure (HF).

METHODS AND RESULTS

PRELIEVE was a prospective, non-randomised, multicentre, first-in-man study in symptomatic HF patients with reduced (HFrEF) or preserved (HFpEF) ejection fraction and pulmonary capillary wedge pressure (PCWP) ≥15 mmHg at rest or ≥25 mmHg during exercise. Here, we provide follow-up data up to 1 year after implantation of the Atrial Flow Regulator (AFR) device. The AFR was successfully implanted in 53 patients (HFrEF n = 24 and HFpEF n = 29). Two patients were not enrolled due to an unsuccessful transseptal puncture. There was one device embolisation into the left atrium, which required surgical removal. One patient experienced a serious procedure-related adverse event (post-procedural bleeding and syncope). All patients with sufficient echocardiography readout confirmed device patency with left-right shunt both at 3 (n = 47/51, 92%) and 12 (n = 45/49, 92%) months. At 3 months, rest PCWP decreased by 5 (-12, 0) mmHg (P = 0.0003, median Q1, Q3). No patient developed a stroke, worsening of right heart function or significant increase of pulmonary artery pressure. Six (6/53, 11%) patients were hospitalised for worsening of HF and three (3/53, 6%) patients died. We observed improvements in New York Heart Association functional class, 6-min walking distance and quality of life (Kansas City Cardiomyopathy Questionnaire) in certain patients.

CONCLUSIONS

Implantation of the AFR device in HF patients was feasible. No shunt occlusion, stroke or new right HF was observed during the 1-year follow-up, with clinical improvements in certain patients.

Study of the effect of Occlutech Atrial Flow Regulator on symptoms, hemodynamics, and echocardiographic parameters in advanced pulmonary arterial hypertension

Optimal sized balloon atrial septostomy improves hemodynamics in advanced pulmonary arterial hypertension. Occlutech Atrial Flow Regulator is designed to provide an atrial septal fenestration diameter titrated according to the age and right atrial pressures. This observational study analyzed symptoms, exercise distance, oxygen saturations, hemodynamics and echocardiographic parameters after Atrial Flow Regulator implantation in patients with syncope or right-heart failure. Patients with high-risk predictors of mortality during septostomy were scrutinized. Thirty-nine patients (9 children) with syncope (34/39) or right-heart failure (27/39) underwent Atrial Flow Regulator implantation without procedural complications. Six-minute walk distance increased from 310 ± 158.2 to 376.4 ± 182.6 m, none developed syncope. Oxygen saturations reduced from 96.4 ± 6.4% to 92 ± 4.9% at rest and further to 80.3 ± 5.9% on exercise. Right atrial pressures reduced from 9.4 ± 5 (2-27) mmHg to 6.9 ± 2.6 (1-12) mmHg, while cardiac index increased from 2.4 ± 0.8 (0.98-4.3) to 3 ± 1 (1.1-5.3) L/min/m² and systemic oxygen transport increased from 546.1 ± 157.9 (256.2-910.5) to 637.2 ± 191.1 (301.3-1020.2) ml/min. Echocardiographic improvement included significant reduction of pericardial effusion and inferior caval congestion at a median follow-up of 37 months. Overall survival improved except two early and one late deaths in high-risk patients. Five of seven patients with advanced disease and key hemodynamic predictors of mortality survived. Acute hemodynamic benefits in pulmonary arterial hypertension after Atrial Flow Regulator were improved cardiac output, systemic oxygen transport, and reduced right atrial pressures. Improvement of symptoms especially syncope, exercise duration, and right ventricular systolic function as well as device patency were sustained on mid-term follow-up. Implantation was safe in all including young children without procedural complications. Mortality was noted only in patients who had high-risk predictors and patients at advanced stage of the disease.

Implantation of an Atrial Flow Regulator in a Child on Venoarterial Extracorporeal Membrane Oxygenator as a Bridge to Heart Transplant: A Case Report

BACKGROUND

Balloon dilation and stenting of the atrial septum are techniques used to unload left heart cavities in acute or end-stage heart failure in children. However, they carry significant risks such as tamponade or device embolization.

CASE PRESENTATION

We report the first case of a child with an end-stage mitochondrial cardiomyopathy on a venoarterial extracorporeal membrane oxygenator as a bridge to heart transplant where an atrial flow regulator device has been implanted.

CONCLUSIONS

This case illustrates the feasibility and safety of atrial flow regulator implantation in this setting. This procedure allowed to wean inotropic support while awaiting heart transplantation.

A New Percutaneous Approach to Treat Combined Right Ventricular and Respiratory Failure: The "Aachen Cannula"

INTRODUCTION

Right ventricular failure (RVF) on its own is a life-threatening condition. Often it manifests as a two-organ failure in the final phase of several lung diseases. Mechanical circulatory support is a proven treatment of RVF but remains challenging. Our objective is to develop a novel, simplified, and minimally invasive cannula approach to treat both RVF and respiratory failure.

METHODS

We conceptualized a dual lumen cannula approach to allow oxygenated right-to-left shunting at an atrial level to decompress right-sided circulation. A minimally invasive approach through percutaneous, transjugular insertion and transseptal placement should enable patients to be non-sedated and even ambulatory. In an iterative design, pre-prototyping, prototyping, and anatomic fitting process, such a cannula was generated and tested in both cadaveric and fluid dynamic studies.

RESULTS

After various modifications and improvements, a 27-Fr 255-mm-long double-lumen cannula with an inner line (oxygenated blood return to patient into the left atrium) of 18 Fr and an inflatable balloon (with a volume of approximately 1 mL) at the outflow tip was produced - one version with a straight head and another one with a curved head. In our anatomic studies, the "Aachen Cannula" allowed an easy transjugular introduction and advancement into the right atrium by Seldinger technique. Transseptal placement was achieved by puncture (Brockenbrough needle) in combination with dilatation and was then secured in place with the stabilizing balloon, even under slight tension. The cannula prototype enabled a flow of up to 3.5 L/min, at which common pressure drops were observed.

CONCLUSION

In conclusion, we successfully conceptualized, designed, and verified a minimally invasive one-cannula approach for the treatment of either isolated right heart failure and even combined RVF and respiratory failure through our transseptal Aachen Cannula. This concept may also be carried out in ambulatory conditions. Moreover, this approach completely avoids recirculation issues and ensures reliable oxygenated coronary as well as cerebral perfusion.