Thrombolytics in VAD management - A single-center experience

Tissue plasminogen activator in left ventricular assist device-related intravascular hemolysis after failed augmented anticoagulation

OBJECTIVES

We sought to examine the efficacy and safety of adding fibrinogen-guided low-dose multi-day Alteplase™ tissue plasminogen activator (tPA) in the management of intravascular hemolysis (IVH) in patients with the HeartMate II (HM-II) continuous flow (CF) left ventricular assist device (LVAD) who failed to achieve IVH resolution with conventional augmented anticoagulation (AAC).

BACKGROUND

IVH in patients with LVAD is often treated with AAC, failing which pump exchange is considered. We hypothesized that a trial of low-dose tPA after failed AAC therapy could resolve IVH and prevent pump exchange in some patients.

METHODS

We performed a retrospective study of 31 HM-II CF LVAD patients admitted to our center from January 2015 to January 2020 for IVH management who received tPA following failed AAC. Primary 6-month outcomes included successful IVH resolution, unsuccessful IVH resolution requiring pump exchange, gastrointestinal bleeding, ischemic and hemorrhagic cerebrovascular accident (CVA), and death.

RESULTS

Thirty-one patients with IVH were treated with tPA following failed AAC. Successful resolution of IVH occurred in 22/31 (71%) patients. Pump exchange occurred in 9/31 (29%) patients. Gastrointestinal bleeding occurred in 7/31 (22.6%) patients. Ischemic CVA occurred in 6/31 (19.4%) patients.

CONCLUSIONS

Management of IVH with administration of low-dose tPA after failed AAC is feasible and may prevent pump exchange in some patients.

Left Ventricular Assist Device Thrombosis: Combined Approach by Echocardiography and Logfiles Review for Diagnosis and Management

Introduction

Left ventricular assist devices are an established therapy for end-stage heart failure. Follow-up of these patients showed complications, such as thrombosis. Our objective was to evaluate the contribution of echocardiography — in association with HeartWare HVAD online logfiles reviews and lactate dehydrogenase titration — for diagnosis and treatment of thrombosis.

Methods

Seventeen episodes of thrombosis were diagnosed in 8/20 patients with HVAD. Diagnosis was made by trans-thoracic echocardiographic blood flow velocities, logfiles review of power consumption and pump flows, and titration of lactate dehydrogenase. Data were collected at baseline routine control (Group A), during thrombosis (Group B), after thrombolysis (Group C).

Results

Thrombolysis was successful in all cases; one patient died of cerebral haemorrhage. Echocardiographic maximal blood flow velocity near the inflow cannula was 598±42 cm/sec (Group B), 379.41±21 cm/sec (Group C), and 378.24±28 cm/sec (Group A) (P<0.00001). In eight (47%) cases, thrombi were visualized in the left ventricle by three-dimensional modality. Logfiles recordings of blood flows were 9.52±0.9 L/min (Group B), 4.02±0.4 L/min (Group C), and 4.04±0.4 L/min (Group A) (P<00001). Power consumption was 5.01±0.7 W (Group B), 3.45±0.2 W (Group C), and 3.46±0.2 W (Group A) (P<0.00001). Lactate dehydrogenase was 756±54 IU (Group B), 234±22 IU (Group A), and 257±36 IU (Group C) (P<0.00001).

Conclusions

Echocardiography of increased maximal velocity near the inflow cannula is a sign of HVAD obstruction. Logfile reviews provide a clear picture of HVAD obstruction. Combination of echocardiographic data and review of logfiles detects signs of left ventricular assist devices thrombosis leading to a successful treatment.

Identification of characteristics, risk factors, and predictors of recurrent LVAD thrombosis: conditions in HeartWare devices

Background

Redictors of repetitive left-ventricular assist device (LVAD)-thrombosis have not been studied yet.

Methods

We identified predictors of recurrent LVAD thrombosis in HeartWare (HVAD) patients in a long-term study from 2010 until 2020. We included all patients with two or more thrombolysis treatments for repetitive HVAD thrombosis and effectiveness of thrombolytic therapy was defined as freedom from stroke, death, another HVAD thrombosis, or surgical device exchange within 30 days after the event. Study endpoints also include all-cause mortality and heart transplantation.

Results

A total of 534 HVAD implantations have been screened, and 73 patients (13.7%) developed first HVAD thrombosis after a median of 10 months (IQR; 6–21 months). 46 of these patients had effective thrombolysis in 71.7% (n = 33/46). After a median of 14 months (IQR 4–32 months) follow-up, 17 patients (51.5%) had developed a second HVAD thrombosis and all were treated with t-PA therapy again, resulting in effectiveness in 76.5% (n = 13/17). The four patients with ineffective t-PA therapy underwent subsequent surgical HVAD exchange. Multiple Cox regression model analysis revealed time interval between HVAD implantation and first thrombosis as an independent risk factor of recurrent thrombosis (HR, 0.93, 95% CI 0.87–0.99, p = 0.031). Kaplan–Meier analysis at 3 year follow-up showed no significant difference in overall survival for recurrent vs non-recurrent thrombosis groups (log-rank test, p = 0.959).

Conclusion

Recurrent HVAD thrombosis mostly appears within 12 months after first thrombosis. Systemic t-PA therapy for recurrent pump thrombosis seems safe, achieving comparable effectiveness rates to initial t-PA therapy. Survival does not differ between patients with or without recurrent HVAD thrombosis.

Medical Management of Recurrent Left Ventricular Assist Device Thrombosis in a Patient With Biventricular Assist Devices

Ventricular assist device (VAD) pump thrombosis is a known complication and while the preferred standard treatment is surgical pump exchange this procedure is not without risk and for some patients the risks are prohibitive. This is a case of a 68-year-old female with bilateral HeartWare ventricular assist devices (HVAD) implanted as destination therapy who presented with signs of recurrent pump thrombosis. Surgical pump exchange was deemed to confer prohibitive risk due to her underlying medical co-morbidities and therefore not an option for treatment. After careful consideration of possible options for treatment, she received systemic thrombolysis (Alteplase 5 mg IV bolus followed by 3 mg/hour infusion for 10 hours through a central line) which was successful. This case highlights, not only the rarity of bilateral VADs as destination therapy, but also demonstrates the safety and efficacy of using systemic thrombolytics in patients with bilateral HVADs for treatment of pump thrombosis.

Left Ventricular Assist Devices 101: Shared Care for General Cardiologists and Primary Care

Ambulatory patients with a left ventricular assist device (LVAD) are increasing in number, and so is their life expectancy. Thus, there is an increasing need for care of these patients by non-LVAD specialists, such as providers in the emergency department, urgent care centers, community-based hospitals, outpatient clinics, etc. Non-LVAD specialists will increasingly come across LVAD patients and should be equipped with the knowledge and skills to provide initial assessment and management for these complex patients. These encounters may be for LVAD-related or unrelated issues. However, there are limited data and guidelines to assist non-LVAD specialists in caring for these complex patients. The aim of our review, targeting primary care providers (both inpatient and outpatient), general cardiologists, and other providers is to describe the current status of durable LVAD therapy in adults, patient selection, management strategies, complications and to summarize current outcome data.

Treatment of Left Ventricular Assist Device Thrombosis: Single-Center Experience

Heart failure is the one of the biggest health problem in the world. Because of limited donors for heart transplant procedures, the ventricular assist device has become a solution for heart failure therapy. With the increase in number of ventricular assist devices, the incidence of complications has also increased. One of the most important life-threatening complications is ventricular assist device thrombosis. Medical therapy and changes in the ventricular assist device are the main therapy methods for ventricular assist device thrombosis. In this study, we showed our clinical experience with treatment of ventricular assist device thrombosis.

Reviewing the use of ventricular assist devices in the elderly: where do we stand today?

INTRODUCTION

Implantation of left ventricular assist devices (LVADS) in older patients appears to be an attractive option in the wake of donor shortage and increasing incidence and prevalence of end stage heart failure. Since the inception of the artificial heart program half a century ago tremendous progress in research and development has led to utilization of more sophisticated devices. VADs have therefore emerged as a successful therapy for extending life with meaningful quality. Areas covered: This review will address the use of LVADS as a bridge to transplantation, destination therapy and comparison of LVAD therapy with alternate list heart transplantation in the elderly population. Expert commentary: Age >70 years is an important aspect when assessing LVAD risk, but other characteristics appear to be better predictors of LVAD survival. Elevated pre-operative creatinine, bilirubin and ischemic etiology predispose to a higher risk of mortality. Creatinine has been shown to be a very powerful predictor in post LVAD survival. Based on the existing literature, the authors suggest an algorithm which could be useful when evaluating patients for LVAD implantation.