Titanium Plug Closure after HeartWare Ventricular Assist Device Explantation in a 15-Year-Old Girl: First U.S. Experience

HeartMate 3 Explantation Using Felt Plug for Ventriculotomy Occlusion

Left ventricular assist devices (LVAD) can be utilized for heart failure patients as a bridge to transplant, bridge to destination, or bridge to recovery. Given the lack of a universally accepted consensus for assessing myocardial recovery, techniques and strategies in LVAD explantation also vary. In addition, the incidence of LVAD explantation remains relatively low, and surgical techniques of explantation continue to be areas of interest. Our approach using a felt-plug Dacron technique is an effective way to preserve left ventricular geometry and cardiac function.

Extracting Mural and Volumetric Growth Patterns of Platelet Aggregates on Engineered Surfaces by Use of an Entity Tracking Algorithm

Thrombosis is a major complication that can occur in both blood-contacting devices and regions and in regions of vascular damage. Microfluidic devices are popular templates to model various thrombogenic settings and to assess conditions that lead to bulk channel occlusion. However, area-averaged measurements miss the opportunity to extract real-time information on thrombus evolution and early dynamics of thrombus formation and propagation, which result in late-stage bulk channel occlusion. To clarify these dynamics, we have developed a standalone tracking algorithm that uses consecutive image connectivity and minimal centroid distance mappings to uniquely index all appearing thrombi in fluorescence time-lapse videos http://links.lww.com/ASAIO/A887 , and http://links.lww.com/ASAIO/A888 . This leads to measurements of all individual aggregates that can in turn be studied as ensembles. We applied tracking to fluorescence time-lapse videos http://links.lww.com/ASAIO/A887 , and http://links.lww.com/ASAIO/A888 of thrombosis across both collagen-functionalized substrate and across the surface of a roughened titanium alloy (Ti6Al4V) at a shear rate of 4000 s -1 . When comparing ensemble-averaged measurements to area-averaged metrics, we unveil immediate, steady thrombus growth at early phases on collagen surfaces and unstable thrombus attachment to roughened Ti6Al4V surfaces on Ti6Al4V surfaces. Additionally, we introduce tracked thrombus eccentricity and fluorescence intensity as additional volumetric measures of thrombus growth that relate back to the primary thrombosis mechanism at play. This work advocates for the complementation of surface macrostate metrics with characteristic thrombus microstate growth patterns to accurately predict critical thrombosis events.

Ventricular assist device support for children with chemotherapy-induced cardiomyopathy and advanced heart failure: Perspectives gained from a single-center experience

BACKGROUND

Guidance and data on ventricular assist device (VAD) support for children with chemotherapy-induced cardiomyopathy, particularly within the first 2 years after chemotherapy, are limited.

METHODS

We performed a single-center retrospective case series, reviewing medical records of children <18 years of age with chemotherapy-induced cardiomyopathy and advanced heart failure (HF) who received durable VAD support.

RESULTS

Six patients met inclusion criteria-5 HeartWare™ HVAD, 1 Berlin Heart EXCOR^® . Median age at cancer diagnosis was 6 years (IQR 4.5-10 years). Median dose of anthracycline received was 540 mg/m² (IQR 450-630 mg/m² ). All patients developed HF within 1 year after initiation of cancer treatment (median 8 months, IQR 6-11.5 months) and were initiated on durable VAD support at a median of 8 months after completion of cancer treatment (IQR 3.3-43.5 months). Four patients had significant right ventricular dysfunction needing oral pulmonary vasodilator therapy, one patient had a major bleeding complication, and two patients had thromboembolic strokes while on VAD support. Median duration of VAD support was 7.5 months (IQR 3-11.3 months). Two patients underwent VAD explant due to recovery of LV function, one died due to cancer progression, and three underwent heart transplantation.

CONCLUSIONS

Durable VAD support should be considered as a therapeutic option for children who have advanced HF due to chemotherapy-induced cardiomyopathy, even within 2 years of completing cancer treatment. A multi-disciplinary approach is essential for appropriate patient selection prior to implant and to ensure comprehensive care throughout the duration of VAD support.

Management of Advanced Heart Failure in Children with Cancer Therapy-Related Cardiac Dysfunction

The evolution of cancer therapies has led to marked improvement in survival of those affected by childhood malignancies, while also increasing the recognition of early and late toxicities associated with cancer therapies. Cardiotoxicity can include cardiomyopathy/heart failure, coronary artery disease, stroke, pericardial disease, arrhythmias, and valvular and vascular dysfunction as a result of exposure to chemotherapy and/or radiation. Anthracyclines remain the most common cause of chemotherapy-induced cardiomyopathy (CCM) with varying clinical presentations including: acute, early onset, and late-onset. Many individuals develop cardiac dysfunction over the long-term, ranging from subclinical cardiac dysfunction to end-stage symptomatic heart failure. The focus of this review is on characterization of symptomatic heart failure in children with cancer therapy-related cardiac dysfunction (CTRCD) primarily due to CCM and utilization of advanced heart failure therapies, including ventricular assist device (VAD) support and heart transplantation, with consideration of unique patient-related factors.

Simple Felt-Plug Closure Technique for Minimally Invasive Removal of a Centrifugal-Flow Left Ventricular Assist Device

As the indications for implanting left ventricular assist devices have expanded, some patients are qualifying for device removal after myocardial recovery. Whereas explantation has been described for previous generations of devices, no standard procedures have been developed. Removal of centrifugal-flow devices has created the need for a plug to seal the apical ventriculotomy after pump removal. However, no commercially available products are available in the United States. We used a novel technique to fashion a plug from Teflon felt and a Dacron graft to enable minimally invasive explantation of a current-generation centrifugal-flow device in a 33-year-old woman.

A detailed explantation assessment protocol for patients with left ventricular assist devices with myocardial recovery

OBJECTIVES

Left ventricular assist device (LVAD) implantation for end-stage heart failure patients has been on the rise, providing a reliable long-term option. For some LVAD patients, longer term LV unloading leads to recovery; hence, the need for evaluating potential myocardial recovery and weaning eligibility has emerged.

METHODS

All patients who underwent contemporary LVAD explantation at our institution between 2009 and 2020 were included in the study. Patients in New York Heart Association I, left ventricular ejection fraction >40%, a cardiac index >2.4 l/min and a peak oxygen intake >50% predicted underwent a 4-phase weaning assessment. A minimally invasive approach using a titanium plug was the surgery of choice in the most recent explants. Kaplan-Meier curves were used to estimate the survival at 1 and 5 years.

RESULTS

Twenty-six patients (17 HeartMate II, 9 HeartWare) underwent LVAD explantation after a median 317 days of support [IQ (212-518)], range 131-1437. Mean age at explant was 35.8 ± 12.7 years and 85% were males. Idiopathic dilated cardiomyopathy was the underlying diagnosis in 70% of cases. Thirteen (48%) patients were on short-term mechanical circulatory support and 60% required intensive care unit admission prior to the LVAD implantation. At 1 year, Kaplan-Meier estimated survival was 88%, whereas at 6 years, it was 77%. The average left ventricular ejection fraction at 1 year post-explant was 44.25% ± 8.44.

CONCLUSIONS

The use of a standardized weaning protocol (echocardiographic and invasive) and a minimally invasive LVAD explant technique minimizes periprocedural complications and leads to good long-term device-free survival rates.

Antiplatelet and Anticoagulant Strategies Following Left Ventricular Assist Device (LVAD) Explantation or Decommissioning: A Scoping Review of the Literature

Mechanical circulatory support using left ventricular assist devices (LVADs) has transformed management of patients with end-stage heart failure with more patients on LVAD therapy surviving long enough to necessitate either device explantation or decommissioning. Usually, there is foreign material retained following these procedures that requires maintaining antiplatelet and/or anticoagulant therapy. However, there is no consensus on optimal management of antiplatelet and anticoagulant therapy following LVAD explantation or decommissioning. We conducted a scoping review of antiplatelet and anticoagulation strategies, searching EMBASE, PubMed and CENTRAL. A total of 15 case reports and series encompassing 38 patient cases were found that met inclusion criteria. There was a heterogeneity of LVAD types and techniques used for explantation and decommissioning. Most reports identified in our review maintained patients on a vitamin K antagonist for at least 3 months post-explantation or decommissioning with or without concomitant antiplatelet therapy with low-dose aspirin. However, there was no single agreed-upon optimal strategy for antiplatelet and anticoagulant use post-procedure. Factors such as the degree of foreign material retained following device explantation or decommissioning and whether there is another indication for anticoagulation or antiplatelet use must be considered. A lack of overall consensus indicates that more studies are needed in this area to establish definitive guidelines around antiplatelet and anticoagulant therapy following LVAD explantation or decommissioning.

Improved 6 Minute Walk Distance and Brain-Type Natriuretic Peptide After Continuous-Flow Ventricular Assist Device Placement in Children

Despite increasing continuous-flow ventricular assist device (CF-VAD) use in children, minimal data exist regarding the functional recovery and rehabilitation potential after device placement. We hypothesized that after CF-VAD implantation, children would demonstrate a time-limited improvement in 6 minute walk distance (6MWD) and brain-type natriuretic peptide (BNP). A retrospective cohort study of 27 patients was conducted, those <18 years of age at a tertiary-care center during the study period. Seventy-four percent were male; median age was 12.7 years. Six minute walk distance and BNP were evaluated within 365 days of implantation. Associations were examined before and after 90 days postimplantation because a plateau in both values was seen after 90 days. Data included 92 6MWD and 341 BNP values. In the first 90 days, 6MWD increased by 12 percent predicted (%P) per 30 days (P < 0.01); with no significant change thereafter, increasing 0.6 %P per 30 days (P = 0.482). In the first 90 days, BNP decreased by 59% per 30 days (P < 0.01); with no significant change thereafter, increasing 1.2% per 30 days (P = 0.561). Six minute walk distance and BNP improved after CF-VAD implantation, with a significant improvement only in the first 90 days. Routine use of 6MWD and BNP can help in assessment of functional recovery in children after CF-VAD placement.

Extracorporeal membrane oxygenation, Berlin, and ventricular assist devices: a primer for the cardiologist

PURPOSE OF REVIEW

Mechanical circulatory support (MCS) has become an indispensable tool in the management of children with impending respiratory and cardiac failure. Though extracorporeal membrane oxygenation (ECMO) was classically the only form of support available to pediatric patients, considerable advances have allowed ventricular assist devices (VADs) to become increasingly utilized in children. This review provides an update of recent advances in ECMO and VAD management in children.

RECENT FINDINGS

The options for mechanical support in infants and small children with end-stage heart failure are limited. As such, the greatest advances in the past decade have come in the successful adoption of the Berlin Heart EXCOR device, with a marked improvement in survival to transplant over ECMO. Further advances have been made in the use of adult VADs in children. For instance, the HeartWare HVAD has been utilized in children as young as 3 years of age, despite being designed for use in adult patients.

SUMMARY

The availability of mechanical support options for children remains limited to ECMO and a small number of VADs. While outcomes of VAD support in pediatric patients have been promising, further study in smaller and more complex pediatric patients is necessary.