Left atrial appendage closure in a patient previously implanted with an interatrial shunt device: a case report.

Patients with previous interatrial shunt device (IASD) implantation may face greater challenges during future left atrial interventional procedures. Herein, we report the first case of left atrial appendage closure (LAAC) in a patient with previous IASD implantation. The patient successfully underwent LAAC using the LAmbre device without complications.

Interatrial Shunt Devices.

Elevated left atrial pressure during exercise is a hallmark of heart failure (HF) and is associated with adverse left atrial remodeling and poor outcomes. To decompress the pressure-overloaded left atrium in patients with HF, several device-based approaches have been developed to create a permanent, pressure-dependent, left-to-right interatrial shunt. Such approaches are currently in various stages of investigations in both HF with reduced ejection fraction (EF) and HF with preserved EF. This review discusses the evolution of the concept of left atrial decompression and summarizes the current landscape of device-based approaches used for left atrial decompression.

Device-based percutaneous treatments to decompress the left atrium in heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) accounts for more than half of heart failure hospital admissions in the last years and is burdened by high mortality and poor quality of life. Providing effective management for HFpEF patients is a major unmet clinical need. Increase in left atrial pressure is the key determinant of pulmonary congestion, with consequent dyspnoea and exercise limitation. Evidence on benefits of medical treatment in HFpEF patients is limited. Thus, alternative strategies, including devices able to reduce left atrial pressure, through an interatrial communication determining a left-right shunt, were developed. This review aims to summarize evidence regarding the use of percutaneous interatrial shunting devices. These devices are safe and effective in improving hemodynamic and clinical parameters, including pulmonary capillary wedge pressure, 6-min walking distance, and New York Heart Association functional class. Data on cardiovascular mortality and re-hospitalization for heart failure are still scarce.

Efficacy of interatrial shunt devices: an opening window to acute pulmonary hypertensive crisis and chronic pulmonary arterial hypertension.

The current study aimed to elucidate the efficacy of interatrial shunt device (IASD) for the treatment of acute pulmonary hypertensive crisis (PHC) and chronic pulmonary arterial hypertension (PAH). After establishing chronic PAH models using dehydrogenized monocrotaline (DHMCT), PAH dogs were implanted with IASDs (group A) or received no intervention (group B). One month later, DHMCT was injected again to establish an acute PHC. The prognosis, hemodynamics, ultrasound cardiography, electrocardiogram, and lung pathology of the dogs were observed. The baseline mean pulmonary arterial pressure increased from 12.70 ± 1.03 to 19.95 ± 1.75 mmHg and established a chronic PAH model 2 months after DHMCT injection (1.50 mg/kg). After an additional injection of DHMCT (1.50 mg/kg) in the chronic PAH model, acute PHC occurred. Mean PAP, sPAP, and pulmonary vascular resistance increased to 22.67 ± 1.80 mmHg, 35.70 ± 1.66 mmHg, and 12.50 ± 3.50 WOOD U, respectively. Cardiac output (CO) decreased to 1.31 ± 0.26 L/min, and the right-to-left shunt caused hypoxemia. The survival rates of the dogs with and those without IASD were 70.0% and 22.2% (P = 0.037), respectively. Six months after PHC, the CO between the dogs with and those without IASD were 1.44 ± 0.11 L/min and 1.18 ± 0.04 L/min (P = 0.028). The long-term survival rates were 50.0% and 22.2%, respectively (P = 0.21). IASD might be efficacious and beneficial for treating acute PHC and chronic PAH, as well as improving prognosis.

Mechanical and interventional support for heart failure with preserved ejection fraction: A review.

INTRODUCTION: Restrictive cardiomyopathy (RCM) and hypertrophic cardiomyopathy (HCM) are two disease processes that are known to progress to heart failure with preserved ejection fraction (HFpEF). Pharmacologic therapies for HFpEF have not improved patient outcomes or reduced mortality in this patient cohort; thus, there continues to be substantial interest in other treatment strategies, including surgical interventions and devices. In this article, we explore and report the current utility of percutaneous therapies and surgically implanted mechanical support in the treatment of patients with HFpEF. RESULTS: Treatment strategies include percutaneous interventions with interatrial shunts, left atrial assist devices (LAADs), and ventricular assist devices (VADs) in various configurations. Although VADs have been employed to treat patients with heart failure with reduced ejection fraction, their efficacy is limited in those with RCM and HCM. A left atrial-to-aortic VAD has been proposed to directly unload the left atrium, but data is limited. Alternatively, a LAAD could be placed in the mitral position and simultaneously unload the left atrium, while filling the left ventricle. CONCLUSION: A left atrial assist device in the mitral position is a promising solution to address the hemodynamic abnormalities in RCM and HCM; these pumps, however, are still under development.

Impact of atrial flow regulator (AFR) implantation on 12-month mortality in heart failure : Insights from a single site in the PRELIEVE study.

BACKGROUND: Implantation of the atrial flow regulator (AFR) to create an interatrial left-to-right shunt has been shown to be safe and feasible to reduce intracardiac filling pressures in patients with heart failure (HF). OBJECTIVES: We aimed to assess the effect of AFR implantation on 12-month mortality and hospitalization rates in patients with reduced (HFrEF) or preserved HF (HFpEF). METHODS: One-year follow-up data from 34 subjects enrolled at a single PRELIEVE center were analyzed. The 12-month predicted mortality was calculated using the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) risk score. Patients were divided into two groups, according to their history of hospitalizations for HF. RESULTS: Study data of 34 patients (HFrEF: 24 [70.6%]; HFpEF: 10 [29.4%]) were assessed. Median follow-up duration was 355 days. In total, 14 (41.2%) patients were hospitalized during the follow-up period and 6 (17.6%) of these patients were hospitalization for HF (HHF). A total of 24 hospitalizations occurred in this period and 8 (33%) hospitalizations were for HHF. The median baseline MAGGIC score was 23 and the median predicted mortality was 13.4/100 patient years. Observed mortality was 3.1/100 patient years. The observed survival (97%) was 10.3% (95% confidence interval 3.6-17.5%, p = 0.004) better than the predicted survival (86.6%). CONCLUSION: Our results suggest that AFR implantation has favorable effects on mortality in patients with heart failure, regardless of ejection fraction. Furthermore, compared to baseline, left ventricular filling pressure (assessed by echocardiography) decreased significantly without right side volume overload at the 1­year follow-up.

Eustachian valve, interatrial shunt, and paradoxical embolism.

Randomized clinical trials demonstrate that percutaneous closure of the patent oval foramen is a safe and effective treatment for secondary prevention of cryptogenic stroke in selected patients. The Eustachian valve is generally considered an incidental finding without any significant pathophysiological consequences in adults. However, a persistent Eustachian valve, particularly a prominent one, is significantly more prevalent in patients with patent oval foramen and cryptogenic stroke, and is associated with adverse outcomes following percutaneous closure. Therefore, the Eustachian valve may not be an incidental finding or an innocent bystander. By directing the blood flow from the inferior caval vein to the interatrial septum, the persistence of a Eustachian valve may prevent spontaneous closure of the oval foramen, and predispose to paradoxical embolism during adulthood. The Eustachian valve should be considered an adjunctive risk factor for paradoxical embolism in patients with patent oval foramen. Furthermore, the Eustachian valve has been included in several risk prediction models to identify patients at the highest risk of paradoxical embolism and such patients may benefit the most from an intervention.

Percutaneous Atrial Septal Defect Closure in Adult Ebstein's Anomaly with Exertional Hypoxemia.

In Ebstein's anomaly, percutaneous atrial septal defect (ASD) closure for the treatment of hypoxemia due to a right-to-left interatrial shunt remains controversial. We report the case of a 40-year-old woman with Ebstein's anomaly who developed cyanosis and shortness of breath on exercise. Her symptoms improved after percutaneous ASD closure and her clinical course has been good during follow-up. The balloon ASD occlusion test, combined with dobutamine stimulation before the procedure, is useful to confirm treatment indication. A prior electrophysiological evaluation is also important because Ebstein's anomaly is often complicated by atrioventricular recurrent tachycardia.

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

PURPOSE OF THE REVIEW: Targeted pharmacotherapies did improve survival rates, exercise capacity, and quality of life (QoL) of PAH patients. However, these pharmacological interventions are expensive and not always accessible. In addition, not all patients do respond similarly to these medications and many will continue to deteriorate. This review aims to discuss the beneficial role of an artificial right-to-left shunt and highlights current interventional devices and outcomes. RECENT FINDINGS: Since patients with preexisting atrial shunts or patients with Eisenmenger's disease show better survival rates, improved exercise capacity, and QoL, PAH patients clinically do benefit from an atrial septostomy by reducing signs of right heart failure, improving left heart filling, cardiac output, and systemic oxygen transport despite hypoxia. However, an uncontrolled septostomy with unrestricted right-to-left shunt bears the risk of acute severe desaturation and death. The Atrial Flow Regulator (AFR device, Occlutech®, Sweden) provides an adjustable shunt size with restricted flow and excellent short-term outcomes. Interventional strategies for PAH palliation are on the rise. The novel AFR device provides a durable and safe option for a controlled right-to-left shunting, thus enabling an individualized management.

Imaging Device Therapy: Essentials for the Imager.

Treatment of patients with heart failure with reduced ejection fraction has evolved. Recently, a fully implantable remote hemodynamic monitoring sensor in the pulmonary artery was approved in the treatment of patients at risk of heart failure readmissions. Several novel devices designed to offload the left atrium by creating a small interatrial shunt are being investigated. Cardiac imaging plays a vital role in the selection process, implantation, and monitoring of individuals with such devices. This article discusses in detail various imaging techniques and key clinical points relating to several cardiac devices used in the treatment of patients with heart failure.

Heart Failure Interventions Targeting Impaired Left Ventricles in Structural Heart Disease.

PURPOSE OF REVIEW: Interventional techniques have been developed for a wide spectrum of mechanisms of heart failure (HF), especially in valvular heart disease and cardiomyopathies (ischaemic cardiomyopathy and hypertrophic cardiomyopathy). In this article, we review recent reports on catheter interventions to treat patients with HF. RECENT FINDINGS: Direct modification using the Parachute device and the REVIVENT-TC device for patients with impaired left ventricle with large infarct scars improves geometry and haemodynamic efficiency, resulting in a reduction of HF symptoms. Interatrial shunt therapy improves symptoms and quality of life in HF patients. Uniquely, left ventricular outflow tract obstruction has also been targeted in patients with transcatheter mitral valve implantation. For advanced stage HF patients with prohibitively high surgical risk, emerging transcatheter interventions make it possible to modify life-limiting symptoms. Further results on HF interventions are expected from ongoing clinical trials.

Left atrial enlargement and clinical considerations in patients with or without a residual interatrial shunt after closure of the left atrial appendage with the WATCHMAN™-device.

BACKGROUND: Interventional closure of the left atrial appendage (LAA) in patients with non-valvular atrial fibrillation, high thromboembolic and bleeding risk or bleeding history is an alternative therapeutic strategy to oral anticoagulation. It is not known if the exclusion of the LAA from the blood circulation affects the left atrial volume (LAV) and consequently its prognostic value or the circulatory performance of the heart in humans. METHODS: We aimed to prospectively assess potential changes in baseline LAV, left ventricular ejection fraction (LVEF), NT-proBNP-level and the covered distance in the 6-min walk-test 6 weeks and 6 months after LAA closure with the WATCHMAN™ device. We used serial 3-dimensional transthoracic and transesophageal echocardiography to assess LAV, residual interatrial shunt and device performance in 58 consecutive patients with successful LAA closure. RESULTS: Accurate 3D-echocardiographic data for LAV measurements were evaluable for 51 (91%) patients. Maximum LAV (LAVmax) at baseline was 102.8 ± 30.8 ml and increased significantly to 107.7 ± 32.8 ml after 6 weeks (p < 0.01) and 113.5 ± 34.2 ml after 6 months (p < 0.01). Minimal LAV (LAVmin) increased from 76.9 ± 29.5 ml at baseline to 81.8 ± 30.2 ml after 45 days (p < 0.01) and 82.1 ± 33.3 ml after 6 months (p < 0.01). Similarly, their indexes to BSA (LAVImax and LAVImin) increased significantly, as well. Patients without a residual left-to-right interatrial shunt showed a significantly higher increase in LAVmax or LAVmin. Baseline LVEF, NT-proBNP-level or the distance covered at the 6-min walk test did not significantly change 6 weeks or 6 months after LAA closure. CONCLUSIONS: LAVmax and LAVmin increase significantly after interventional LAA closure. LA enlargement does not correlate with clinical progression of heart failure. Persistent left-to-right interatrial shunt counteracts the LA enlargement. A reduced LA compliance after exclusion of the LAA from the blood circulation with consecutive increase in LA pressure may be a potential cause of LA enlargement and warrants further investigation. TRIAL REGISTRATION: German Clinical Trials Register ID: DRKS00010768 ; Registration Date 07.07.2016.

Rationale and Design of the Reduce Elevated Left Atrial Pressure in Patients With Heart Failure (Reduce LAP-HF) Trial.

OBJECTIVE: Heart failure with preserved ejection fraction (HFpEF) is characterized by elevated left atrial pressure during rest and/or exercise. The Reduce LAP-HF (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure) trial will evaluate the safety and performance of the Interatrial Shunt Device (IASD) System II, designed to directly reduce elevated left atrial pressure, in patients with HFpEF. METHODS: The Reduce LAP-HF Trial is a prospective, nonrandomized, open-label trial to evaluate a novel device that creates a small permanent shunt at the level of the atria. A minimum of 60 patients with ejection fraction ≥40% and New York Heart Association functional class III or IV heart failure with a pulmonary capillary wedge pressure (PCWP) ≥15 mm Hg at rest or ≥25 mm Hg during supine bike exercise will be implanted with an IASD System II, and followed for 6 months to assess the primary and secondary end points. Safety and standard clinical follow-up will continue through 3 years after implantation. Primary outcome measures for safety are periprocedural and 6-month major adverse cardiac and cerebrovascular events (MACCE) and systemic embolic events (excluding pulmonary thromboembolism). MACCE include death, stroke, myocardial infarction, or requirement of implant removal. Primary outcome measures for device performance include success of device implantation, reduction of PCWP at rest and during exercise, and demonstration of left-to-right flow through the device. Key secondary end points include exercise tolerance, quality of life, and the incidence of heart failure hospitalization. CONCLUSION: Reduce LAP-HF is the first trial intended to lower left atrial pressure in HFpEF by means of creating a permanent shunt through the atrial septum with the use of a device. Although the trial is primarily designed to study safety and device performance, we also test the pathophysiologic hypothesis that reduction of left atrial pressure will improve symptoms and quality of life in patients with HFpEF.

Effects of an interatrial shunt on rest and exercise hemodynamics: results of a computer simulation in heart failure.

BACKGROUND: A treatment based on an interatrial shunt device has been proposed for counteracting elevated pulmonary capillary wedge pressure (PCWP) in patients with heart failure and mildly reduced or preserved ejection fraction (HFpEF). We tested the theoretical hemodynamic effects of this approach with the use of a previously validated cardiovascular simulation. METHODS AND RESULTS: Rest and exercise hemodynamics data from 2 previous independent studies of patients with HFpEF were simulated. The theoretical effects of a shunt between the right and left atria (diameter up to 12 mm) were determined. The interatrial shunt lowered PCWP by ~3 mm Hg under simulated resting conditions (from 10 to 7 mm Hg) and by ~11 mm Hg under simulated peak exercise conditions (from 28 to 17 mm Hg). Left ventricular cardiac output decreased ~0.5 L/min at rest and ~1.3 L/min at peak exercise, with corresponding increases in right ventricular cardiac output. However, because of the reductions in PCWP, right atrial and pulmonary artery pressures did not increase. A majority of these effects were achieved with a shunt diameter of 8-9 mm. The direction of flow though the shunt was left to right in all of the conditions tested. CONCLUSIONS: The interatrial shunt reduced left-sided cardiac output with a marked reduction in PCWP. This approach may reduce the propensity for heart failure exacerbations and allow patients to exercise longer, thus attaining higher heart rates and cardiac outputs with the shunt compared with no shunt. These results support clinical investigation of this approach and point out key factors necessary to evaluate its safety and hemodynamic effectiveness.

In vivo fluid dynamics of the Ventura interatrial shunt device in patients with heart failure.

AIMS: Interatrial shunts are under evaluation as a treatment for heart failure (HF); however, their in vivo flow performance has not been quantitatively studied. We aimed to investigate the fluid dynamics properties of the 0.51 cm orifice diameter Ventura shunt and assess its lumen integrity with serial transesophageal echocardiography (TEE). METHODS AND RESULTS: Computational fluid dynamics (CFD) and bench flow tests were used to establish the flow-pressure relationship of the shunt. Open-label patients from the RELIEVE-HF trial underwent TEE at shunt implant and at 6 and 12 month follow-up. Shunt effective diameter (Deff) was derived from the vena contracta, and flow was determined by the continuity equation. CFD and bench studies independently validated that the shunt's discharge coefficient was 0.88 to 0.89. The device was successfully implanted in all 97 enrolled patients; mean age was 70 ± 11 years, 97% were NYHA class III, and 51% had LVEF ≤40%. Patency was confirmed in all instances, except for one stenotic shunt at 6 months. Deff remained unchanged from baseline at 12 months (0.47 ± 0.01 cm, P = 0.376), as did the trans-shunt mean pressure gradient (5.1 ± 3.9 mmHg, P = 0.316) and flow (1137 ± 463 mL/min, P = 0.384). TEE measured flow versus pressure closely correlated (R2 ≥ 0.98) with a fluid dynamics model. At 12 months, the pulmonary/systemic flow Qp/Qs ratio was 1.22 ± 0.12. CONCLUSIONS: When implanted in patients with advanced HF, this small interatrial shunt demonstrated predictable and durable patency and performance.

Long-term impact of transcatheter closure interatrial shunts on disabling migraine.

BACKGROUNDS: Effectiveness of patent foramen ovale (PFO) closure on relief of migraine, is still unclear. We sought to analyse the long-term (>10 years) effects of interatrial septal shunt repair on disabling migraine performing a retrospective non-randomised study. METHODS: Clinical records of patients with disabling, medication-refractory migraine and PFO or significant ASD referred to our centre for closure from 2006 to 2018, were analysed. RESULTS: Forty -six patients (38 female, mean age 40.0 ± 3.7 years) with PFO and 32 patients with significant ASD (28 female, mean age 38.0 ± 4.1 years) submitted to transcatheter closure had a pre-existing disabling migraine with mean Migraine Disability Assessment Score (MIDAS) of 35.8 ± 4.7. After a mean follow-up of 118.2 ± 19.1 months (range 96 to 144), 72 out of 78 patients were still followed-up: in all subjects, aura was abolished, and migraine improved also in patients without aura. The mean MIDAS significantly decreased from baseline value (p < 0.01). Complete migraine resolution was associated in PFO patients with a shorter history of migraine, a more severe thrombophilic profile, a more severe Right-to-Left Shunt (RLS) and larger left atrial diameter and volume, and in ASD patients with bidirectional shunt. CONCLUSIONS: Device-based repair of PFO/ASD in patients with migraine was associated with abolition of aura and symptoms reduction in the long-term period.

Design and Rationale of the V-Wave Shunt MitraClip Study.

Heart failure (HF) and moderate-to-severe mitral regurgitation (MR) with residual elevations in left atrial pressure (LAP) after MitraClip may remain symptomatic and experience subsequent HF readmissions. The V-Wave interatrial shunt system is a permanent interatrial septal implant that shunts blood from the left-to-right atrium and serves to continuously unload the left atrium. Although the V-Wave shunt has previously been studied in patients with HF, the safety and feasibility of its deployment at the time of the MitraClip procedure is unknown. The V-Wave Shunt MitraClip Study (NCT04729933) is an early feasibility study that aims to demonstrate the safety and efficacy of implantation of the V-Wave shunt device at the time of MitraClip procedure. Patients with moderate-to-severe secondary MR with left ventricular ejection fraction 20% to 50% and New York Heart Association functional class III/IV symptoms despite optimal medical therapy, residual mean LAP ≥20 mm Hg after MitraClip, and mean LAP-right atrial pressure difference ≥5 mm Hg are included. The primary safety end point is a composite outcome of all-cause death, stroke, myocardial infarction device embolization, cardiac tamponade, or device-related re-intervention or surgery at 30 days. Patients will be followed up to 5 years. Enrollment is ongoing, with 30-day results expected by the end of 2024. The V-Wave Shunt Mitraclip Study aims to demonstrate the safety and efficacy of the implantation of the V-Wave interatrial shunt device at the time of index MitraClip placement which may serve as an adjunctive method by which continuous left atrial unloading may be achieved.

Left Atrial Hemodynamics and Clinical Utility in Heart Failure.

Comprehensive knowledge of the left atrium (LA) and its pathophysiology has emerged as an important clinical and research focus in the heart failure (HF) arena. Although studies on HF focusing on investigating left ventricular remodeling are numerous, those on atrial structural and functional changes have received comparatively less attention. Studies on LA remodeling have recently received increasing attention, and LA pressure (LAP) has become a novel target for advanced monitoring and is a potential therapeutic approach for treating HF. Various devices specifically designed for the direct measurement of LAP have been developed to optimize HF treatment by reducing LAP. This review focuses on LA hemodynamic monitoring and effective LAP decompression.

A 'twice closed' patent foramen ovale: a case report of percutaneous management of a residual interatrial shunt in a patient with persistent migraine symptoms.

Background: Residual interatrial shunt following percutaneous patent foramen ovale (PFO) closure is a rare complication that can be associated with persistent migraine. Case summary: A 32-year-old woman with a history of percutaneous PFO closure due to a previous coronary paradoxical embolism and a condition of drug-refractory migraine underwent transoesophageal echocardiography (TOE) to investigate further recurrent migraine attacks. A partial displacement of a PFO occluder device was found, and it was successfully treated through the fluoroscopic and TOE-guided positioning of a second occluder in overlap with the previous one. The patient reported no more migraine attacks at the 6-month follow-up visit. Discussion: Residual interatrial shunt should be suspected in patients with persistent migraine and a history of percutaneous PFO closure. Fluoroscopic and TOE-guided closure of residual interatrial shunt with a second PFO occlude device seems to be a safe and clinically effective strategy to manage persistent migraine.