2019 EACTS Expert Consensus on long-term mechanical circulatory support

A case series of patients with left ventricular assist devices and concomitant mechanical heart valves

Mechanical heart valves left in situ at the time of left ventricular assist device (LVAD) implantation are thought to potentially increase the risk of thromboembolism. Recommendations exist to replace dysfunctional mechanical mitral valves and any mechanical aortic valves at the time of LVAD implantation. Due to potential increases in cardiopulmonary bypass time and associated comorbidities with valve replacement, leaving a functional mechanical valve in place at LVAD implantation has been suggested to be a safe option. We retrospectively reviewed all patients with prior mechanical mitral or aortic valves undergoing LVAD implantation at our center between 2012 and 2017. Echocardiograms were read by a single cardiologist to assess for mechanical valve dysfunction. We identified 15 patients. Five patients had major bleeding requiring transfusion. On follow-up, 2 patients had hemorrhagic stroke and 2 had transient ischemic attach/ischemic stroke. In addition, 2 patients had LVAD thrombosis and 2 patients had LVAD driveline malfunction. Mild mechanical valve regurgitation was identified on follow-up echocardiograms of 2 patients. Rate of complications in patients with mechanical valves undergoing LVAD implantation was comparable to that reported for the general LVAD population. Leaving a functional mechanical valve in place at the time of LVAD implantation could be a reasonable alternative to valve replacement. More data are required to further guide patient care in these individuals.

Right Ventricular Function in Chronic Heart Failure: From the Diagnosis to the Therapeutic Approach

There is growing attention for the study of the right ventricle in cardiovascular disease and in particular in heart failure. In this clinical setting, right ventricle dysfunction is a significant marker of poor prognosis, regardless of the degree of left ventricular dysfunction. Novel echocardiographic methods allow for obtaining a more complete evaluation of the right ventricle anatomy and function as well as of the related abnormalities in filling pressures. Specific and effective therapies for the right ventricle dysfunction are still not well defined and this represents the most difficult and important challenge. This article focuses on available diagnostic techniques for studying right ventricle dysfunction as well as on the therapies for right ventricle dysfunction.

Minimally invasive surgery for left ventricular assist device implantation is safe and associated with a decreased risk of right ventricular failure

Background

Right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation is associated with significant mortality and morbidity. The objective of this study was to determine pre- and postoperative risk factors associated with the occurrence of RVF after LVAD implantation.

Methods

This retrospective study included 68 patients who received LVADs between 2010 and 2018 either for bridge to transplant (40 patients, 58.8%) or bridge to destination therapy (28 patients, 41.2%). RVF after LVAD implantation was defined according to the INTERMACS classification. The primary endpoint was the occurrence of RVF. The secondary endpoints were hospital mortality and morbidity and long-term survival.

Results

The majority of patients (61.8%) had an INTERMACS profile 1 (36.8%) or 2 (25.0%). The LVAD was implanted either by sternotomy (37 patients, 54.4%) or thoracotomy (31 patients, 45.6%). RVF after LVAD implantation was observed in 32 patients (47.1%). In univariate analysis, an elevated serum glutamic oxaloacetic transaminase (SGOT) (P=0.028) and a high preoperative vasoactive inotropic score (VIS) (P=0.028) were significantly associated with an increased risk of RVF, whereas the implantation of LVAD through a thoracotomy approach was associated with a significant reduction in this risk (P=0.006). The multivariate analysis demonstrated that only the thoracotomy approach was significantly associated with decreased risk of RVF (odds ratio =0.33, 95% confidence interval: 0.17–0.96; P=0.042). Hospital mortality was 53.1% and 5.6% in the RVF and control groups, respectively (P<0.0001). The incidence of stroke and postoperative acute renal failure were significantly increased in the RVF group compared with the control group. The survival after LVAD implantation was 33.5%±9.0% and 85.4%±6.0% at 1 year in the RVF and control groups, respectively (P<0.0001).

Conclusions

LVAD implantation by thoracotomy significantly reduced the risk of postoperative RVF. This surgical approach should, therefore, be favored.

Long-term follow-up of patients supported with the HeartWare left ventricular assist system

The aim of the present study is to report our long-term experience with the HeartWare Ventricular Assist System (HVAD). Between July 2009 and February 2018, a total of 103 patients (mean age 50.0 ± 14.4, range 28-74 years; 22 females) received HVAD implantation in a single center institution. A total of 26 (25.4%) patients were in cardiogenic shock preoperatively and received extracorporeal life support (ECLS) prior to HVAD implantation. The aim of left ventricular assist device (LVAD) implantation was bridge to transplantation (BT) in 59 (57.3%), destination therapy (DT) in 28 (27.2%), and bridge to decision in 16 (15.5%). There were 211.1 total patient years of support. Mean survival was 2.05 ± 2.14 years. Kaplan-Meier analysis showed an overall survival rate of 69.7%, 56.7%, 46.0%, and 25.0% at 1, 2, 4, and 8 years, respectively. A total of 23 patients (22.3%) died during the hospital stay. Of them 65.2% (15 patients) were preoperatively in cardiogenic shock (INTERMACS 1). Sub-analysis of the BT patients showed a mean survival of 2.45 ± 2.29 years with a survival rate of 85.1%, 75.1%, 67.2%, and 44.8% at 1, 2, 4, and 8 years, respectively. Among them, 20 patients received heart transplantation on follow-up. Mean survival of DT patients was 2.18 ± 1.91 years with a survival rate of 67.9%, 49.0%, and 25.1% at 1, 2, and 4 years, respectively. At latest follow-up in September 2018, 26 patients (25.24%) were still on LVAD. A total of five patients completed 6 years on LVAD, of them two were supported over 8 years. The most common adverse event reported was gastrointestinal bleeding requiring rehospitalization (0.161 EPPY). A total of 19 patients reported disabling stroke. Pump thrombosis was diagnosed in six patients (5.8%) (0.02 EPPY), of them four patients underwent pump exchange. To the best of our knowledge, this is the longest experience with HVAD reported so far. Patients supported with an HVAD show a satisfactory long-term survival. Further multicenter evaluations are needed to confirm these single-center results.

Randomized trial of a left ventricular assist device as destination therapy versus guideline-directed medical therapy in patients with advanced heart failure. Rationale and design of the SWEdish evaluation of left Ventricular Assist Device (SweVAD) trial

AIMS

Patients with advanced heart failure (AdHF) who are ineligible for heart transplantation (HTx) can become candidates for treatment with a left ventricular assist device (LVAD) in some countries, but not others. This reflects the lack of a systematic analysis of the usefulness of LVAD systems in this context, and of their benefits, limitations and cost-effectiveness. The SWEdish evaluation of left Ventricular Assist Device (SweVAD) study is a Phase IV, prospective, 1:1 randomized, non-blinded, multicentre trial that will examine the impact of assignment to mechanical circulatory support with guideline-directed LVAD destination therapy (GD-LVAD-DT) using the HeartMate 3 (HM3) continuous flow pump vs. guideline-directed medical therapy (GDMT) on survival in a population of AdHF patients ineligible for HTx.

METHODS

A total of 80 patients will be recruited to SweVAD at the seven university hospitals in Sweden. The study population will comprise patients with AdHF (New York Heart Association class IIIB-IV, INTERMACS profile 2-6) who display signs of poor prognosis despite GDMT and who are not considered eligible for HTx. Participants will be followed for 2 years or until death occurs. Other endpoints will be determined by blinded adjudication. Patients who remain on study-assigned interventions beyond 2 years will be asked to continue follow-up for outcomes and adverse events for up to 5 years.

CONCLUSION

The SweVAD study will compare survival, medium-term benefits, costs and potential hazards between GD-LVAD-DT and GDMT and will provide a valuable reference point to guide destination therapy strategies for patients with AdHF ineligible for HTx.

Patients with left ventricle assist devices presenting for thoracic surgery and lung resection: tips, tricks and evidence

PURPOSE OF REVIEW

Over a thousand left ventricular-assist device (LVAD) implants were performed for heart failure destination therapy in 2017. With increasing survival, we are seeing increasing numbers of patients present for noncardiac surgery, including resections for cancer. This article will review the relevant literature and guidelines for patients with LVADs undergoing thoracic surgery, including lung resection.

RECENT FINDINGS

The International Society for Heart and Lung Transplant Mechanically Assisted Circulatory Support Registry has received data on more than 16 000 patients with LVADs. Four-year survival is more than 60% for centrifugal devices. There are increasing case reports, summaries and recommendations for patients with LVADs undergoing noncardiac surgery. However, data on thoracic surgery is restricted to case reports.

SUMMARY

Successful thoracic surgery requires understanding of the LVAD physiology. Modern devices are preload dependent and afterload sensitive. The effects of one-lung ventilation, including hypoxia and hypercapnia, may increase pulmonary vascular resistance and impair the right ventricle. Successful surgery necessitates a multidisciplinary approach, including thorough preoperative assessment; optimization and planning of intraoperative management strategies; and approaches to anticoagulation, right ventricular failure and LVAD flow optimization. This article discusses recent evidence on these topics.

ECMO in cardiogenic shock and bridge to heart transplant

Purpose

The aim of this review is to discuss the role of extracorporeal membrane oxygenation (ECMO) in cardiogenic shock and its use to bridge patients to heart transplantation.

Methods and results

Consideration of published literature reveals indications for ECMO in cardiogenic shock and tools for patient selection, adequate evidence of its efficacy, its advantages when compared with other temporary mechanical circulatory support devices and details of its use as a bridge to decision, bridge to recovery, bridge to bridge (durable ventricular assist device) and bridge to heart transplant.

Conclusion

ECMO is invaluable in treating patients with medically refractory profound cardiogenic shock and allows for cardiac recovery or planning for permanent heart replacement treatments.

Validation of non-invasive ramp testing for HeartMate 3

Aims

Ramp testing in the postoperative period can be used to optimize left ventricular assist device (LVAD) speed for optimal left ventricular (LV) unloading. We tested the hypothesis that a non‐invasive echocardiographic ramp test post‐HeartMate 3 implantation improves LV unloading immediately after and 1–3 months after as compared with before the test. We also tested a secondary hypothesis that speed adjustments during echocardiography‐guided ramp testing do not worsen right ventricular (RV) function immediately after and 1–3 months after.

Methods and results

We retrospectively reviewed data from patients who underwent an echocardiographic ramp test. A total of 14 out of 19 patients were clinically stable and were enrolled. Adequate LV unloading was defined as no more than mild mitral regurgitation, and intermittent aortic valve (AV) opening or closed AV, and reduction of left ventricular end‐diastolic diameter (LVEDD); and for the follow‐up measurement, decreased NT‐proBNP. Median (interquartile range) time from implantation to ramp test was 27 (16; 56) days, and median time from ramp test to follow‐up echocardiography was 55 (47; 102) days. Median LVAD speed achieved during ramp testing was 5550 (5375; 6025) revolutions per minute (rpm), and median final LVAD speed was 5200 (5000; 5425) rpm. Ramp testing resulted in final LVAD speed increase in 11 (79%) patients and a median net change of 200 (200; 300) rpm. Speed adjustments after ramp testing resulted in improved LVAD unloading that was achieved in additional 3 (21%) patients who were not originally optimized. RV function did not worsen significantly during ramp testing or at final LVAD speed.

Conclusions

The echocardiographic ramp test allowed LVAD speed adjustment and optimization and improved LV unloading during ramp testing and at final speed with no evidence of worsening of RV function.

Bleeding in critical care associated with left ventricular assist devices: pathophysiology, symptoms, and management

Chronic heart failure (HF) is a growing health problem, and it is associated with high morbidity and mortality. Left ventricular assist devices (LVADs) are nowadays an important treatment option for patients with end-stage HF not only as a bridging tool to heart transplantation but also, as a permanent therapy for end-stage HF (destination therapy). The use of LVAD is associated with a high risk for bleeding complications and thromboembolic events, including pump thrombosis and ischemic stroke. Bleeding is the most frequent complication, occurring in 30% to 60% of patients, both early and late after LVAD implantation. Although the design of LVADs has improved over time, bleeding complications are still the most common complication and occur very frequently. The introduction of an LVAD results in an altered hemostatic balance as a consequence of blood-pump interactions, changes in hemodynamics, acquired coagulation abnormalities, and the strict need for long-term anticoagulant treatment with oral anticoagulants and antiplatelet therapy. LVAD patients may experience an acquired coagulopathy, including platelet dysfunction and impaired von Willebrand factor activity, resulting in acquired von Willebrand syndrome. In this educational manuscript, the epidemiology, etiology, and pathophysiology of bleeding in patients with LVAD will be discussed. Because hematologist are frequently consulted in cases of bleeding problems in these individuals in a critical care setting, the observed type of bleeding complications and management strategies to treat bleeding are also reviewed.

Medical Management of Left Ventricular Assist Device Patients: A Practical Guide for the Nonexpert Clinician

Left ventricular assist devices (LVADs) provide short- or long-term circulatory support to improve survival and reduce morbidity in selected patients with advanced heart failure. LVADs are being used increasingly and now have expanded indications. Health care providers across specialties will therefore not only encounter LVAD patients but play an integral role in their care. To accomplish that, they need to understand the elements of LVAD function, physiology and clinical use. This article provides a concise overview of the medical management of LVAD patients for nonexpert clinicians. Our presentation includes the basics of LVAD physiology, design, and operation, patient selection and assessment, medical management, adverse event identification and management, multidisciplinary care, and management of special circumstances, such as noncardiac surgery, cardiac arrest, and end-of-life care. The clinical examination of LVAD patients is unique in terms of blood pressure and heart rate assessment, LVAD "hum" auscultation, driveline and insertion site inspection, and device parameter recording. Important potential device-related adverse events include stroke, gastrointestinal bleeding, hematologic disorders, device infection, LVAD dysfunction, arrhythmias, and heart failure. Special considerations include the approach to the unconscious or pulseless patient, noncardiac surgery, and palliative care. An understanding of the principles presented in this paper will enable the nonexpert clinician to be effective in collaborating with an LVAD center in the assessment, medical management, and follow-up of LVAD patients. Future opportunities and challenges include the improvement of device designs, greater application of minimally invasive surgical implantation techniques, and management of health economics in cost-constrained systems like those of Canada and many other jurisdictions.