Outpatients on mechanical circulatory support

Successful Perioperative Management of a Patient with the Left Ventricular Assist Device for Brain Tumor Resection: Case Report and Review of the Literature

Heart failure is the leading cause of death in the United States. Our increasingly aged population will contribute to an increased incidence and prevalence of heart failure, thereby augmenting the need for mechanical circulatory devices. Here we present the first successful resection of a brain tumor in a left ventricular device- (LVAD-) dependent patient with increased intracranial pressure and address pertinent perioperative anesthetic considerations and management.

Home discharge and out-of-hospital follow-up of total artificial heart patients supported by a portable driver system

To enhance ambulation and facilitate hospital discharge of total artificial heart (TAH)–supported patients, we adapted a mobile ventricular assistance device (VAD) driver (Excor) for TAH use and report on the performance of Excor-driven TAH patients discharged home. Ten patients stabilized on a TAH, driven by the CSS (“Circulatory Support System”), were progressively switched over to the Excor in hospital over 14 days as a pilot, with daily hemodynamics and laboratory parameters measured. Twenty-two stable TAH patients were subsequently placed on the Excor, trained, and discharged home. Clinical and hemodynamic parameters were followed. All pilot study patients were clinically stable on the Excor, with no decrease in TAH output noted (6.3 + 0.3 L/min [day 1] vs. 5.8 + 0.2 L/min [day 14], p = 0.174), with a trend suggesting improvement of both hepatic and renal function. Twenty-two TAH patients were subsequently successfully discharged home on the portable driver and were supported out of hospital for up to 598 days (range, 2–598; mean = 179 ± 140 days), remaining ambulatory, New York Heart Association (NYHA) class I or II, and free of readmission for 88.5% of the time of support. TAH patients may be effectively and safely supported by a mobile drive system. As such, the utility of the TAH may be extended to support patients beyond the hospital, at home, with overall ambulatory freedom.

Cardiac assist devices: present status and future opportunities

Over the last 20 years, continuous progress has been made in the technology and clinical applications of mechanical circulatory support systems for the treatment of the most severe forms of cardiac failure. In a few pioneering centers, their efficacy has been demonstrated in selected groups of patients. This experience enables assessment of the state-of-the-art devices and prediction of likely future developments.

End-stage heart failure and mechanical circulatory support: feasibility of discharge from hospital

BACKGROUND.: Due to the shortage of donor hearts, mechanical circulatory support is increasingly being used as a bridge to transplantation. In order to allow for more widespread use of ventricular assist devices it is mandatory that patients are not continuously hospitalised. We present the results of our experience with patients with end-stage heart failure, discharged from hospital after implantation of a ventricular assist device and followed in an outpatient setting. METHODS.: After an intensive training and education programme, focusing on the management of the percutaneous driveline and instructions on how to handle in case of an alarm or malfunction of the device, patients were discharged. They were followed in the outpatient department. All regular and unplanned visits were registered, including readmissions. RESULTS.: Twenty-seven patients treated with a ventricular assist device were discharged from hospital. There were 37 extra visits, of these, 27 were device related resulting in 21 readmissions (0.78/patient). We treated eight infectious episodes in four patients, all device related. Furthermore seven thromboembolic episodes occurred in four patients. One patient died because of multiorgan failure seven weeks after he was readmitted with an urosepsis. In our experience of 11.4 patient years at home while on the device, only 5% of the time was spent in hospital for complications. In comparison with patients on an assist device who stayed in hospital until transplantation, there were no more complications. CONCLUSION.: This study demonstrates that patients with end-stage heart failure, treated with a ventricular assist device, can be safely discharged from hospital, with an acceptable rate of readmissions. It results in a fair quality of life, with a high degree of independence of the patient. (Neth Heart J 2007;15:45-50.).

[Improvements in implantable mechanical circulatory support systems : literature overview and update]

In recent years, ventricular assist devices (VAD) supporting the left (LVAD), the right (RVAD) or both ventricles (BVAD) have rapidly emerged as the standard of care for advanced heart failure patients. Both the numbers and ages of patients in which they are used are rising worldwide, especially when used as a permanent support (bridge to destination, BTD). Due to the continuing lack of donor organs, these devices now represent a viable alternative to bridge patients to transplantation (BTT), with a 1-year survival rate of 86%. BTD, especially in long-term support, might be a valid, and the sole, option for those patients in whom heart transplantation is contraindicated. Patient selection, pre- and intra-operative preparation, as well as the timing of VAD implantation are important factors critical to successful circulatory support. While BTT remains the goal in the majority of patients, the number of permanent VADs (i. e. BTD) is rising significantly. Although explantation of a VAD system as a bridge to recovery (BTR) can be considered in only a small number of patients, it represents a very special part of this therapy modality.

Intracranial hemorrhage surgery on patients on mechanical circulatory support: a case series

BACKGROUND

Cardiac disease is the leading cause of death in the United States and late-stage heart failure is associated with a high level of morbidity and mortality. The ventricular assist devices and extracorporeal membrane oxygenators are the mainstay of mechanical circulatory support devices for the patients with extremely low cardiac output. However, they come at a price of significant risk factors, including intracranial hemorrhage. The incidence of intracranial hemorrhage on extracorporeal membrane oxygenators and on ventricular assist devices is 37% and 13% to 14%, respectively.

METHODS/RESULTS

The cases in this series focus on the risks of ICH and the decompressive craniotomies that were carried out on patients while they were on mechanical circulatory support. The intraoperative anesthetic management for patients on mechanical circulatory support for the noncardiothoracic anesthesiologist is highlighted.

CONCLUSIONS

The results of recent cardiothoracic surgery trials have led to an increase of surgical management instead of medical management in the treatment of heart failure. Although most agree with the immediate reversal of anticoagulation and antiplatelet therapy, there is no standard protocol for restarting anticoagulation or antiplatelet therapy after craniotomy in this population. The standard practices of resuscitation and ACLS including inotropes, vasopressors, and vasodilators (with the exception of chest compressions that can dislodge the devices), can be used as needed. The identification of cardiothoracic surgeons and perfusionists who are available for immediate assistance as and when required during the surgery and transportation is an important factor.

Clinical management of continuous-flow left ventricular assist devices in advanced heart failure

Continuous-flow left ventricular assist devices (LVAD) have emerged as the standard of care for advanced heart failure patients requiring long-term mechanical circulatory support. Evidence-based clinical management of LVAD-supported patients is becoming increasingly important for optimizing outcomes. In this state-of-art review, we propose key elements in managing patients supported with the new continuous-flow LVADs. Although most of the presented information is largely based on investigator experience during the 1,300-patient HeartMate II clinical trial, many of the discussed principles can be applied to other emerging devices as well. Patient selection, pre-operative preparation, and the timing of LVAD implant are some of the most important elements critical to successful circulatory support and are principles universal to all devices. In addition, proper nutrition management and avoidance of infectious complications can significantly affect morbidity and mortality during LVAD support. Optimizing intraoperative and peri-operative care, and the monitoring and treatment of other organ system dysfunction as it relates to LVAD support, are discussed. A multidisciplinary heart failure team must be organized and charged with providing comprehensive care from initial referral until support is terminated. Preparing for hospital discharge requires detailed education for the patient and family or friends, with provisions for emergencies and routine care. Implantation techniques, troubleshooting device problems, and algorithms for outpatient management, including the diagnosis and treatment of related problems associated with the HeartMate II, are discussed as an example of a specific continuous-flow LVAD. Ongoing trials with other continuous-flow devices may produce additional information in the future for improving clinical management of patients with these devices.

Influence of inflow cannula length in axial-flow pumps on neurologic adverse event rate: results from a multi-center analysis

BACKGROUND

The application of axial-flow pumps in patients with end-stage heart failure reveals a significantly reduced infectious complication rate as compared with rates observed with pulsatile devices. The remaining adverse event rate relates mainly to thromboembolic complications with neurologic consequences. We investigated the dependence of the neurologic adverse event rate on the length of the inflow cannula.

METHODS

A total of 216 consecutive patients with an axial-flow pump (INCOR; Berlin Heart GmbH, Berlin, Germany) were included in a retrospective multi-center analysis. In 138 patients, a short inflow cannula (24-mm tip length into the left ventricle), and in 78 patients a long inflow cannula (tip length 34 mm) was applied.

RESULTS

Patients with a long inflow cannula (LC) demonstrated a better survival rate than those with a short inflow cannula (SC) at the end of the observation period (LC, 63.4%; SC, 52.9%; p = 0.05). The thromboembolic adverse event rate was also significantly lower. Only 3 of the 78 patients (3.8%) with an LC had a thromboembolic adverse event (thromboembolic events per patient-year = 0.11) as compared with 32 (23.2%) of SC patients (thromboembolic events per patient-year = 0.50, p < 0.001).

CONCLUSIONS

Patients with a long inflow cannula had a better survival rate and a lower incidence of cerebrovascular adverse events than patients with a short inflow cannula.

Ventricular assist devices in children: current achievements and future perspectives

Mechanical circulatory support systems for the treatment of acute and chronic heart failure are now available for use in several clinical situations and are designed for different indications and support times. In children, particularly in small infants, extracorporeal membrane oxygenation and centrifugal pumps have been most widely used in the past. These systems are preferred for support after cardiac operations and for use in patients who have concomitant respiratory failure, but they are suitable for short-term application only and intensive care is obligatory. VADs are designed for long-term application and allow patients to be discharged home. Pneumatic pulsatile VADs have been available in pediatric sizes since 1992. Currently at our institution, 74 children have been supported with pediatric extracorporeal VADs for up to 14 months. In the past five yr, a notable rise in survival has been achieved by improvements in pump design and pre- and post-operative management. We have been able to discharge 78% of the infants under one yr old. In this review, our current VAD experience in children will be presented in the light of improvements in decision-making, device technology, and implantation techniques, and in coagulation monitoring and anticoagulation. Additionally, new developments in the field of pediatric assist devices will be presented.

Left Ventricle Load Impedance Control by Apical VAD Can Help Heart Recovery and Patient Perfusion: A Numerical Study

The aim of this work is to investigate the dependence between left ventricular load impedance control by an apical ventricular assist device (VAD) and the consequent benefits for pathological heart recovery. A pathological left ventricle with 34% contractility has been simulated in the assisted and nonassisted conditions. By means of an extended Kalman filter, left ventricular pressure-volume loops have been partially estimated and ventricular as well as circulatory quantities inferred. The heart operation mode, based on cardiac energetic criteria, is imposed by controlling the VAD filling phase. In the assisted condition, results show that the left ventricle end-diastolic volume, left atrial pressure, and wall stress all decrease; stroke volume, ejection fraction, ventricular efficiency, aortic pressure, and cardiac output all increase. Benefits are also evident for the right ventricle and systemic and pulmonary circulation. The strategy outlined in this work also shows that good results for heart recovery are achievable and a possible way to improve the functional properties of commercial pulsatile VADs.

Home Discharge Experience With the Thoratec TLC-II Portable Driver

With the growing success and expanded use of ventricular assist devices, home discharge with independent ambulation and self-care are now important issues. We describe our initial home discharge experience with the Thoratec TLC-II portable drive. Patients discharged home were required to have five outpatient excursions (three monitored) before discharge and were seen weekly after discharge. Between August 2000 and December 2004, 14 patients (average age, 57 years) were placed on the TLC-II portable driver. One patient on the TLC-II portable driver had left ventricular assist device removal after 50 days of support but before discharge. Thirteen patients were discharged from the hospital with average time at home of 62 days (range, 16 to 243 days). After discharge, the TLC-II portable driver was maintained in the auto mode at average settings of 78 beat rate, 5.1 L/min flow rate, 204 mm Hg ejection pressure, and -8.4 mm Hg fill vacuum. A total of 5852 alarms (average, 6.7 per day) were recorded with 2373 battery reminders (41%), 1922 occlusion alarms during sleep (33%), and 1461 no-fill signals (25%). There were no readmissions for device malfunction, emergency battery utilization or back-up unit use. These results demonstrate that the Thoratec TLC-II portable driver is safe, reliable, and can be effectively managed at home.

Technology Insight: use of ventricular assist devices in children

Mechanical circulatory support systems for the treatment of end-stage heart failure are now available for a wide variety of clinical situations and support times. Extracorporeal membrane oxygenation and centrifugal pump circuits have been most widely used in children, particularly in small infants. These systems are preferred for support after cardiac operations and for use in patients who have concomitant respiratory failure, but are suitable for short-term application only and intensive care is obligatory. True ventricular assist devices (VADs) qualify for long-term application and allow patients full mobilization. These features are important in patients awaiting heart transplantation as well as in those with myocarditis and cardiomyopathy, who might achieve complete cardiac recovery. Pneumatic pulsatile VADs have been available in pediatric sizes since 1992. At our institution, VAD use lasting from several days to 14 months in 70 infants and children with myocarditis and cardiomyopathy has led to a notable rise in survival in the past 5 years. We have been able to discharge 78% of the infants under 1 year old. In this review we present current VAD experience in children in the light of improvements in decision making, device technology, implantation techniques, and in coagulation monitoring and anticoagulation.

Improved early outcome for end-stage dilated cardiomyopathy in children

OBJECTIVE

To review the impact of management changes on the early outcomes of end-stage dilated cardiomyopathy in children.

METHODS

We conducted a retrospective study of all consecutive children with end-stage dilated cardiomyopathy who received hospital treatment since 1992. Over the past 3 years the following management changes were made: (1) more aggressive use of mechanical cardiac assistance; (2) high priority listing for transplantation; and (3) ABO incompatible transplants for infants. Outcomes for 46 patients admitted between 1992 and 1999 (group I) were compared with 53 patients between 2000 and March 2003 (group II).

RESULTS

In group I, 12 (26%) patients received mechanical support with recovery in 3 and transplantation in 5 (1 died). In group II, 19 (36%) patients received extracorporeal membrane oxygenation, with recovery in 5 and transplantation in 12 (all survived). The use of mechanical assistance was associated with high morbidity related to bleeding, end-organ failure, and long-term mechanical ventilation. Five patients in group II received ABO incompatible transplants and all survived. There have been no episodes of rejection or need for increased immunosuppressive therapy. Hospital mortality has been significantly reduced (group I, 37% vs group II, 11%; P <.05).

CONCLUSIONS

Recent refinements in the management of end-stage dilated cardiomyopathy in children have significantly reduced early mortality. Identification of markers of early myocardial recovery and development of mechanical devices for longer term and more physiologic support are essential to achieve further improvements in outcome.