Predictors of survival in patients bridged to transplantation with the thoratec VAD device: a single-center retrospective study on more than 100 patients

Successful treatment of fulminant myocarditis with intra-aortic balloon pump counterpulsation combined with immunoglobulin and glucocorticoid in a young male adult

Background

Fulminant myocarditis (FM) is a serious non-specific inflammatory disease of the myocardium. FM tends to occur in adolescents and the course of the disease progresses rapidly. It is prone to cardiogenic shock (CGS) and multiple organ failure (MOF) with high mortality. We report a case of FM with CGS and MOF in a young male who was successfully treated with intra-aortic balloon pump counterpulsation (IABP) combined with intravenous immunoglobulin (IVIG) and glucocorticoid (GC).

Case summary

A 21-year-old previously healthy man presented with fever, headache, and chest tightness. He came to the hospital for emergency treatment. The laboratory data showed that the levels of serum cardiac troponin I (cTnI), N-terminal B-type natriuretic peptide (NT-proBNP), myocardial zymogram, and neutrophils increased. Echocardiography showed pericardial effusion and decreased left ventricular systolic function. ECG showed diffuse ST-segment elevation. He was clinically diagnosed with FM and admitted to the intensive care unit for treatment. Within 48 h of admission, the clinical course of the patient deteriorated rapidly, with CGS accompanied by MOF, high atrioventricular block (AVB), and ventricular tachycardia (VT). After using mechanical circulatory support (MCS) therapy with IABP, IVIG, GC, continuous renal replacement therapy (CRRT), and mechanical ventilation complicated with a temporary cardiac pacemaker, he recovered normal cardiac function. He made a full recovery and was discharged home on day 21.

Discussion

For patients with FM, early diagnosis, close monitoring, timely use of MCS devices, and active comprehensive treatment are very important. MCS devices such as IABP can become lifesaving tools for the treatment of FM.

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.

Successful bridge to recovery in fulminant myocarditis using a biventricular assist device: a case report

Background

Fulminant myocarditis is a life-threatening disease, and myocardial damage expands the right ventricle as well as the left ventricle in some cases. There is a mortality rate of over 40% in patients with fulminant myocarditis who need mechanical circulatory support by peripheral venoarterial extracorporeal membrane oxygenation.

Case presentation

We report a case of a 27-year-old Japanese woman who was successfully bridged to recovery by using a biventricular assist device. She was diagnosed with fulminant myocarditis, and peripheral venoarterial extracorporeal membrane oxygenation was established on the same day. Her left ventricular ejection fraction rapidly decreased from 40% to 5% in 3 days and weaning from venoarterial extracorporeal membrane oxygenation was deemed difficult. Therefore, we performed a ventricular assist device implantation on day 4. A left ventricular assist device was implanted first. However, adequate blood flow did not circulate to the left side of her heart because of right-sided heart failure. Thus, an additional implant of a right ventricular assist device was performed during the operation. Her left ventricular ejection fraction recovered to 50% on day 10. The biventricular assist device was successfully removed on day 14. She has not experienced worsening of biventricular function during her follow-ups for 4 years.

Conclusions

Ventricular assist device therapy should be considered if there is no improvement in cardiac function in patients with fulminant myocarditis regardless of several days of support by venoarterial extracorporeal membrane oxygenation. A right ventricular assist device should always be implemented when necessary because biventricular involvement is not uncommon in fulminant myocarditis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13256-017-1466-1) contains supplementary material, which is available to authorized users.

Paediatric mechanical circulatory support with Berlin Heart EXCOR: development and outcome of a 23-year experience

This paper reviews the development and establishment of the Berlin Heart EXCOR® (BHE®) as a paediatric mechanical circulatory support and reports our entire experience with regard to indications, timing of implantation and explantation and outcome. The Berlin group reported the first successful paediatric bridge to transplantation using a pulsatile pneumatic paracorporeal biventricular assist device, the BHE®, in 1990 in an 8-year-old boy with end-stage heart failure and coarctation of the aorta. This experience prompted them to develop miniaturized pump systems for children through the company Berlin Heart Mediproduct GmbH. The development and production of BHE® to support paediatric patients with heart failure then began. Between 1990 and 2013, the BHE® has been implanted in 122 patients (median age 8.64 years, range 3 days to 17 years) with heart failure, who were inotrope-dependent or switched from extracorporeal membrane oxygenation support or had postcardiotomy low-output syndrome. Thirty-five patients were <1 year old (median 125 days). The aetiology of heart failure included cardiomyopathy in 56 (median age 9.14 years), fulminant myocarditis in 17 (median age 8.2 years), end-stage congenital heart disease in 18 (median age 6.4 years), postcardiotomy heart failure (after correction of congenital heart disease) in 28 (median age 9.6 years) and transplant graft failure in 3 (median age 12.5 years). The overall median duration of implantation was 63.6 (range 1-841) days. Fifty-six children eventually underwent orthotopic heart transplantation. Eighteen patients had myocardial recovery and were weaned successfully. They had entirely normal cardiac function after a range of 4-10 years after surgery. At the time of this report, five patients were still on support, with a duration of 354-369 days. Forty-three patients died on the system from loss of peripheral circulatory resistance, multiorgan damage, sepsis or haemorrhagic or thrombotic complications. Re-exploration because of bleeding was necessary in 22 patients. Pump exchange because of thrombus formation in the valves was necessary 35 times. With the introduction of a modified anticoagulation regimen in 2000, the pump exchange rate has decreased. The BHE® can reliably support the circulation at any age for long periods with good results. It is now an established treatment for children with heart failure of any aetiology.

Relationship between early inflammatory response and clinical evolution of the severe multiorgan failure in mechanical circulatory support-treated patients

Background. The mechanical circulatory support (MCS) is an effective treatment in critically ill patients with end-stage heart failure (ESHF) that, however, may cause a severe multiorgan failure syndrome (MOFS) in these subjects. The impact of altered inflammatory response, associated to MOFS, on clinical evolution of MCS postimplantation patients has not been yet clarified. Methods. Circulating cytokines, adhesion molecules, and a marker of monocyte activation (neopterin) were determined in 53 MCS-treated patients, at preimplant and until 2 weeks. MOFS was evaluated by total sequential organ failure assessment score (tSOFA). Results. During MCS treatment, 32 patients experienced moderate MOFS (tSOFA < 11; A group), while 21 patients experienced severe MOFS (tSOFA ≥ 11) with favorable (B group) or adverse (n = 13, C group) outcomes. At preimplant, higher values of left ventricular ejection fraction (LVEF) and estimated glomerular filtration rate (eGFR) were the only parameter independently associated with A group. In C group, during the first postoperative week, high levels of interleukin-8 (IL-8) and tumor necrosis factor (TNF)-α, and an increase of neopterin and adhesion molecules, precede tSOFA worsening and exitus. Conclusions. The MCS patients of C group show an excessive release to IL-8 and TNF-α, and monocyte-endothelial activation after surgery, that might contribute to the unfavourable evolution of severe MOFS.

Parameters associated with short- and midterm survival in bridging to lung transplantation with extracorporeal membrane oxygenation

Patients with terminal lung failure may be bridged to lung transplantation (LTX) by extracorporeal membrane oxygenation (ECMO). With the present shortage of donor organs and the high level of invasiveness of ECMO treatment, appropriate selection criteria for bridge to transplant need to be defined. We report retrospective data from 26 patients on ECMO listed for LTX. Seven patients were successfully transplanted (LTX-s). Six patients survived until transplantation, but died intra- or post-operatively (LTX-ns). Thirteen patients died before transplantation (Fail). There was no difference between LTX-s and the 19 overall non-survivors (NS) prior to ECMO initiation with regard to demographic data or ventilator parameters except for higher PaO2 /FiO2 in the LTX-s. Time on ECMO pre-LTX did not differ in the LTX-s and LTX-ns groups. SOFA score was lower in LTX-s when compared to LTX-ns before ECMO (p = 0.0155), during bridging (p = 0.028), and right before transplantation (p = 0.0038). Maximal bilirubin during bridging and bilirubin prior to transplantation was markedly elevated in the LTX-ns group [4.2 (2.4-4.7) vs. 1.1 (0.8-2.0) mg/dL; p = 0.0266 and 1.6 (1.2-3.0) vs. 0.5 (0.5-0.5) mg/dL; p = 0.0047). Bridging to LTX is a challenging but viable option for selected patients. Special consideration should be given to hepatic function.

Decision tree for adjuvant right ventricular support in patients receiving a left ventricular assist device

BACKGROUND

Right ventricular (RV) failure is a significant complication after implantation of a left ventricular assist device (LVAD). It is therefore important to identify patients at risk a priori. However, prognostic models derived from multivariate analyses have had limited predictive power.

METHODS

This study retrospectively analyzed the records of 183 LVAD recipients between May 1996 and October 2009; of these, 27 later required a RVAD (RVAD(+)) and 156 remained on LVAD only (RVAD(-)) until transplant or death. A decision tree model was constructed to represent combinatorial non-linear relationships of the pre-operative data that are predictive of the need for RVAD support.

RESULTS

An optimal set of 8 pre-operative variables were identified: transpulmonary gradient, age, right atrial pressure, international normalized ratio, heart rate, white blood cell count, alanine aminotransferase, and the number of inotropic agents. The resultant decision tree, which consisted of 28 branches and 15 leaves, identified RVAD(+) patients with 85% sensitivity, RVAD(-) patients with 83% specificity, and exhibited an area under the receiver operating characteristic curve of 0.87.

CONCLUSIONS

The decision tree model developed in this study exhibited several advantages compared with existing risk scores. Quantitatively, it provided improved prognosis of RV support by encoding the non-linear, synergic interactions among pre-operative variables. Because of its intuitive structure, it more closely mimics clinical reasoning and therefore can be more readily interpreted. Further development with additional multicenter, longitudinal data may provide a valuable prognostic tool for triage of LVAD therapy and, potentially, improve outcomes.

Clinical strategies and outcomes in advanced heart failure patients older than 70 years of age receiving the HeartMate II left ventricular assist device: a community hospital experience

OBJECTIVES

The primary objective of this study was to determine outcomes in left ventricular assist device (LVAD) patients older than age 70 years.

BACKGROUND

Food and Drug Administration approval of the HeartMate II (Thoratec Corporation, Pleasanton, California) LVAD for destination therapy has provided an attractive option for older patients with advanced heart failure.

METHODS

Fifty-five patients received the HeartMate II LVAD between October 5, 2005, and January 1, 2010, as part of either the bridge to transplantation or destination therapy trials at a community hospital. Patients were divided into 2 age groups: ≥ 70 years of age (n = 30) and < 70 years of age (n = 25). Outcome measures including survival, length of hospital stay, adverse events, and quality of life were compared between the 2 groups.

RESULTS

Pre-operatively, all patients were in New York Heart Association functional class IV refractory to maximal medical therapy. Kaplan-Meier survival for patients ≥ 70 years of age (97% at 1 month, 75% at 1 year, and 70% at 2 years) was not statistically different from patients <7 0 years of age (96% 1 month, 72% at 1 year, and 65% at 2 years, p = 0.806). Average length of hospital stay for the ≥ 70-year age group was 24 ± 15 days, similar to that of the < 70-year age group (23 ± 14 days, p = 0.805). There were no differences in the incidence of adverse events between the 2 groups. Quality of life and functional status improved significantly in both groups.

CONCLUSIONS

The LVAD patients ≥ 70 years of age have good functional recovery, survival, and quality of life at 2 years. Advanced age should not be used as an independent contraindication when selecting a patient for LVAD therapy at experienced centers.

Age and preoperative total bilirubin level can stratify prognosis after extracorporeal pulsatile left ventricular assist device implantation

BACKGROUND

In Japan, the TOYOBO left ventricular assist device (LVAD) has been commercially available for heart failure patients as of 2010, but clinical risk stratification before implantation has not been widely performed.

METHODS AND RESULTS

In the present study data from 47 patients (age 38.6 ± 14.6 [SD] years, male 74.5%, non-ischemic 74.5%) implanted with a TOYOBO LVAD between November 2002 and February 2010 were analyzed. Kaplan-Meier survival analysis showed significantly higher mortality in the patients who had cardiogenic shock preoperatively (P = 0.031). Multivariate analysis revealed that the preoperative total bilirubin level (odds ratio [OR] 1.312, P < 0.001) and age (OR 1.076, P = 0.013) were independent risk factors for death. Perioperative necessity of a right ventricular assist device was also an independent risk factor for poor prognosis.

CONCLUSIONS

LVAD implantation is preferable before the patient experiences hemodynamic collapse. The preoperative total bilirubin level can be used to predict prognosis after device implantation in end-stage heart failure patients.

Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS)-defined morbidity and mortality associated with pediatric ventricular assist device support at a single US center: the Stanford experience

BACKGROUND

The use of ventricular assist devices (VADs) to bridge pediatric patients to heart transplantation has increased dramatically over the last 15 years. In this report, we present the largest US single-center report of pediatric VAD use to date. We present detailed descriptions of morbidity and mortality associated with VAD support, using standard Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) criteria for pediatrics to facilitate the comparison of these results to other studies.

METHODS AND RESULTS

We retrospectively identified 25 patients younger than 18 years with 27 episodes of mechanical circulatory support using VADs as bridge to heart transplantation from January 1998 to December 2007. Survival to transplant for the entire cohort was 74%. The most common major morbidities, as defined by INTERMACS criteria for a pediatric population, were respiratory failure, major localized infections, major bleeding events, hepatic dysfunction, and right heart failure. Major neurological events occurred in 48% of the study population. The median time to the first occurrence of an adverse event was less than 14 days for respiratory failure, right heart failure, major localized infection, and major bleeding. Patients who died before transplantation had significantly more adverse events per day of support than did those who were successfully transplanted. Episodes of major bleeding, tamponade, acute renal failure, respiratory failure, and right heart failure were all associated with increased risk of mortality.

CONCLUSIONS

INTERMACS criteria can be successfully used to analyze pediatric VAD outcomes. These data serve as a baseline for future studies of VAD support in children and indicate good survival rates but considerable morbidity.

Risk factor analysis of long-term support with left ventricular assist system

BACKGROUND

This study was designed to elucidate the key factors for successful long-term support with a left ventricular assist system (LVAS) in the situation where heart transplantation is rarely available.

METHODS AND RESULTS

From 1992 to 2008, 106 patients underwent 121 LVAS implantations at Osaka University Hospital (Toyobo: 77; Novacor: 18; HeartMate: 14; Jarvik2000: 8; EvaHeart: 2; DuraHeart: 2). Risk factors for infection were early on the former implanted period (odds ratio (OR) 3.30), Toyobo (OR 2.25), mechanical right heart support (OR 2.30) and cardiopulmonary bypass time (OR 1.01). Left atrium as the inflow site was the risk factor for cerebrovascular events (OR 2.84). Older age (OR 1.04) and mechanical right heart support (OR 4.70) were risk factors for mortality. Risk factors for requiring mechanical right heart support were preoperative extracorporeal membranous oxygenation support (OR 5.641), serum total bilirubin (OR 1.11) and serum creatinine (OR 2.46). On the basis of the risk analysis for mortality, patients were divided into 2 subgroups (low and high risk) and the respective cumulative survival at 1 year after LVAS implantation was 75.2% and 25.0%.

CONCLUSIONS

Appropriate selection of device, patient and the timing of implantation and less invasive operation are important for successful long-term LVAS support.

Total artificial heart--concepts and clinical use

End-stage congestive heart failure remains the leading cause of death in the United States. Despite advances in medical treatment, it also remains the most common reason for admission to the hospital. The gold standard of treatment for the failing heart, orthotopic heart transplantation, is limited by a shortage of donor hearts. There are also a significant number of patients who are not transplant candidates due to comorbid conditions and/or inability to tolerate immunosuppressive therapy. To meet the need for this latter group, the medical field has embraced ventricular assist device (VAD) therapy to extend survival and improve quality-of-life for the end-stage cardiac patient. This therapy, however, has been currently limited to the failing left ventricle and is still fraught with complications that limit long-term and widespread use. The total artificial heart, as currently available with two devices, is rapidly becoming the treatment of choice for biventricular failure.

Histology of the explanted hearts of children transplanted for dilated cardiomyopathy

There is little information as to the histology of the explanted hearts of children transplanted for presumed dilated cardiomyopathy. We therefore aimed to describe the histology of these explants. Thirty-six children [mean age 7.4 years (range 0.1-17)] transplanted for dilated cardiomyopathy were identified. Based on histological examination of the explanted hearts patients were classified into three groups: severe inflammation, mild to moderate inflammation, and minimal or no inflammation. Cell death/damage and fibrosis were also scored. Duration of symptoms and degree of support at transplant were ascertained from the case notes. Two patients had severe confluent inflammation, nine mild or moderate focal inflammation, and 25 minimal or no inflammation. The degree of inflammation and fibrosis did not correlate with the interval between presentation and transplant (p = 0.37 and p = 0.78). Patients requiring inotropes or ventricular assist had a shorter time interval between presentation and transplant (p = 0.017) although these levels of support were not associated with the degree of inflammation or fibrosis (p = 0.90 and 0.5). We conclude that the explanted hearts of one-third of children transplanted for presumed cardiomyopathy have some degree of inflammation. Histological findings are not associated with symptom duration or support required.

Results of a multicenter clinical trial with the Thoratec Implantable Ventricular Assist Device⁎⁎Thoratec Corporation, Pleasanton, Calif

OBJECTIVE

The Thoratec Implantable Ventricular Assist Device (Thoratec Corporation, Pleasanton, Calif) can be used for univentricular or biventricular support in patients with a body surface area as low as 1.3 m(2). Results of the multicenter clinical trial are reviewed.

METHODS

Between October 2001 and June 2004, a total of 39 patients at 12 institutions were supported with the Thoratec Implantable Ventricular Assist Device. Twenty-four patients (62%) received left ventricular assist devices and 15 (38%) received biventricular assist devices. Indications included bridge to transplantation (n = 30) and postcardiotomy failure (n = 9). The control group included 100 patients from the Food and Drug Administration approval submissions for the paracorporeal version of the ventricular assist device.

RESULTS

Twenty-eight male and 11 female patients, with mean age of 48 years (16-71 years) and body surface area of 1.9 m(2) (1.3-2.4 m2) were supported for 3938 patient-days (10.8 patient-years). Mean left ventricular assist device flow index on the first postoperative day was 2.5 +/- 0.5 L/(min x m2). Mean duration of support was 101 days (9-597 days). Eighteen patients were discharged after a mean duration of 96 days. There were no ventricular assist device failures. Complications included 13 cases of bleeding requiring reexploration (33.3%), 1 embolic and 2 hemorrhagic strokes (7.7%), 5 driveline infections (12.8%), and 2 pocket infections (5%). Support to successful outcomes was 70% for bridge to transplantation and 67% for postcardiotomy recovery, versus historical results for the paracorporeal ventricular assist device of 69% for bridge to transplantation and 48% for postcardiotomy recovery.

CONCLUSION

The Thoratec Implantable Ventricular Assist Device is a new implantable pulsatile ventricular assist device that allows hospital discharge for patients as a bridge to transplantation or for postcardiotomy failure. It is the first Food and Drug Administration-approved implantable ventricular assist device with biventricular capability.

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.

Mechanical Circulatory Support as a Bridge to Heart Transplantation: What Remains? Long-term Emotional Sequelae in Patients and Spouses

BACKGROUND

Implantation of a ventricular assist device (VAD) reduces short-term mortality and morbidity and provides patients with reasonable quality of life even though it may also be a long-lasting emotional burden. This study was conducted to analyze the long-time emotional consequences of VAD implantation, followed by heart transplantation in patients and spouses.

METHODS

This cross-sectional study used the Impact of Event Scale-Revised (IES-R) Version, recording avoidance, intrusion, and hyperarousal, to investigate symptoms of post-traumatic stress disorder (PTSD), and VAD-related fears and concerns. The study cohort comprised 38 patients (36 men, 2 women) and 27 spouses (26 women, 1 man), 6 to 135 months post-operatively.

RESULTS

Seven (26%) of the 27 spouses but none of the patients met the criteria for PTSD. Patients who were operated at the early stage of our VAD program (82.0 +/- 31.4 months between implantation and evaluation) were significantly more likely to have a spouse with PTSD syndromes than those whose operation took place later on (42.1 +/- 31.1 months, p = 0.007). Patients with higher avoidance scores and a higher level of hyperarousal were significantly more often affiliated with a PTSD spouse than those with lower avoidance (p = 0.008) and hyperarousal scores (p = 0.001). Spouses displayed significantly higher scores in all IES-R dimensions, and they worried more about device-related problems (malfunctioning, pain, infection, and stroke) than the patients themselves. The noise of the device system was not a crucial issue.

CONCLUSION

Our study found that implantation of a VAD, followed by transplantation, does not lead to PTSD in patients but it does in their spouses in the long run. Their emotional well being deserves much closer attention.

Improvement in Survival After Mechanical Circulatory Support With Pneumatic Pulsatile Ventricular Assist Devices in Pediatric Patients

BACKGROUND

Pediatric size pneumatically driven extracorporeal ventricular assist devices (VAD) for infants and small children were introduced into clinical routine in 1992. In the initial period, the results in infants were poor. Since then, several improvements have been introduced with regard to the cannulas, connectors, heparin coating of the blood pump inner surface, anticoagulant treatment and coagulation monitoring, and earlier decision-making in favor of pump implantation before irreversible shock has set in.

METHODS

Since 1990 and as of January 1, 2005, 62 Berlin Heart Excor systems have been implanted in patients below 18 years of age at our institution. The patients were divided into two groups according to the period of treatment: period 1, devices implanted between 1990 and 1998 (n = 34), and period 2, devices implanted between 1999 and 2004 (n = 28). We compared our experience during the earlier and later periods.

RESULTS

There were no significant differences in the preoperative patient data between the two periods except for time of support (17.9 +/- 27.7 days versus 53.2 +/- 83.9 days, p = 0.001). In period 1, more patients needed a biventricular VAD whereas in period 2, more patients were effectively treated with a left VAD (p = 0.05). In the later period, the chest could be primarily closed in a significantly higher percentage of infants (0% versus 89%, p = 0.012), and more infants could be extubated on the VAD (0% versus 55%, p = 0.16). Discharge from the hospital after either weaning from the system or heart transplantation was achieved for 35% in period 1 and for 68% in period 2 (p = 0.029). Whereas in period 1 there were no survivors in the group of children younger than 1 year old, during period 2, survival in this age group was similar to that of the two groups of older children (p = 0.024). There was a significant improvement in the discharge rate in period 2 in patients with cardiomyopathy (43% versus 76%, p = 0.045) and postcardiotomy heart failure (0% versus 57%, p = 0.01).

CONCLUSIONS

Earlier implantation of VADs, heparin coating of the blood pumps, and substantial modifications in cannula design, anticoagulation, and the coagulation monitoring regimen have led to a significant increase in the survival and discharge rate, especially among children under 1 year of age. The pediatric size Berlin Heart Excor VAD is a valuable option as a bridge to heart transplantation or recovery for children suffering from cardiogenic shock.

Cardiac failure: Mechanical support strategies

OBJECTIVE

Mechanical support of the circulation is necessary when heart failure becomes refractory to medical support and is typically applied when organ dysfunction occurs as a result of hypoperfusion. However, in timing the intervention, it is important to apply mechanical support before multiple organ failure occurs. The objective of this work is to review the current strategies for mechanical circulatory support in patients with refractory cardiac failure.

DESIGN

A review of the use of mechanical circulatory support is presented for patients with refractory cardiac failure.

PATIENTS

Data are taken from human studies that were selected to best exemplify the results that may be obtained from various forms of mechanical circulatory support.

INTERVENTIONS

Commonly applied forms of mechanical support include mechanical ventilatory support, intraaortic balloon counterpulsation, and hemodialysis or ultrafiltration. If these measures fail, mechanical support of the circulation with ventricular assist devices is possible in specialized centers with expertise in the implantation and management of these devices. The decision to pursue mechanical circulatory support in the critically ill patient is based on the cause of acute decompensation, the potential reversibility of the condition, and the possibility for other treatments to improve the underlying condition or, in highly selected cases, heart transplantation. Newer forms of ventricular assistance that require less surgery are becoming available and may allow use in a broader range of critically ill patients.

MAIN RESULTS

There is a range of means to mechanically support the circulation in patients with advanced heart failure.

CONCLUSIONS

A variety of means to support the circulation have found application in the treatment of patients with refractory heart failure. More work is required to best identify populations who will benefit from the therapy and to refine the therapy to reduce associated risks.

Clinical outcomes in pediatric patients implanted with Thoratec ventricular assist device

Most mechanical circulatory support devices are designed for adult patients; however, some can be successfully applied to pediatric patients. The rates of complications and patient survival to transplant or native heart recovery after implantation of the Thoratec ventricular assist device (VAD) (Thoratec Corp, Pleasanton, CA) in children and adolescents were determined from the company's voluntary registry. As of January 2005, 209 patients (mean age 14.5 years; range 5 to 18 years) have been supported with the Thoratec VAD. Mean patient weight was 57 kg (range, 17 to 118 kg), and patients had a mean body surface area of 1.6 m2 (range, 0.73 to 2.3 m2). The major etiologies necessitating VAD support included cardiomyopathy (55.0%), acute myocarditis (25.4%), and end-stage congenital heart disease (5.8%). Mean duration of VAD support was 44 days (range, 0 to 434 days). Patient survival to transplantation or native heart recovery was 68.4%. Patients with cardiomyopathy and acute myocarditis had 74.1% and 86.0% survival, respectively, with only 27.3% survival in patients having congenital heart disease. The overall survival rate in smaller children (body surface area, <1.3 m2) was similar at 51.7%, although the incidence of congenital heart disease was higher.

Characteristics of Patients Who Die With Heart Failure and a Low Ejection Fraction in the New Millennium

BACKGROUND

Therapies for heart failure (HF) with a low ejection fraction (EF) have delayed disease progression and prolonged survival, but the implications of these therapies on the end stages of HF have not been examined.

METHODS AND RESULTS

Patients seen by the Brigham and Women's cardiomyopathy service with an EF < or =35%, at least 1 outpatient visit or at least 30 days of follow-up who died between January 1, 2000, and October 20, 2003, were evaluated retrospectively. Of the 160 patients who died since 2000, 80 (50%) were outpatients. In the 6 months before death, 93% of patients had New York Heart Association (NYHA) class III or IV symptoms. The NYHA class, clinical characteristics, medications, and comorbidities differed little between inpatient and outpatient deaths. Renal insufficiency and hyponatremia were worse in the months preceding death than at the time of death (creatinine: 3.2 versus 2.3 mg/dL, P < .0001; sodium: 128 versus 135 mmol/L, P < .0001, respectively). Death was considered sudden in only 21% of patients.

CONCLUSION

Deaths in the current era of HF management occur in patients with long-standing HF characterized by biventricular dysfunction and advanced symptoms. Most deaths are heralded by hyponatremia, acute on chronic renal insufficiency, and frequent hospitalizations.

CardioWest Total Artificial Heart: Bad Oeynhausen Experience

BACKGROUND

The use of ventricular assist devices (VAD) has become a widely accepted therapeutic option. However, there are still limitations to the patient collective eligible for VAD placement, who might therefore benefit from the implantation of a total artificial heart. We present the first German single-center experience with the CardioWest total artificial heart (TAH) (SynCardia Systems, Tucson, AZ) in 42 patients.

METHODS

Between February 2001 and December 2003, 42 patients (37 men, 5 women, mean age 51 +/- 13 years) received a TAH at our Center. Their body surface area ranged between 1.5 and 2.4 (mean, 1.9 +/- 0.19) m2. All patients were in persistent cardiogenic shock in spite of maximum inotropic support and had numerous preoperative risk factors (intraaortic balloon pumping, mechanical ventilation, acute renal failure, previous cardiac surgery, recent cardiopulmonary resuscitation).

RESULTS

Duration of support was 1 to 291 days. Eleven patients (26%) underwent successful transplantation; 9 of them could be discharged home. Twenty-two patients died under support, 21 of them from multiple organ failure and 1 patient from a technical problem. Nine patients are still on the device, 4 of them at home after the original CardioWest console was replaced by the Berlin Heart EXCOR driver (Berlin Heart, Berlin, Germany). Exceptional results were achieved in patients with cardiogenic shock after cardiac surgery or after acute myocardial infarction.

CONCLUSIONS

Against the background of the extremely poor preoperative situation of our patients, the overall survival rate of 48% can be considered as favorable. A prospective, randomized study is planned to find out whether patients with idiopathic dilated or ischemic cardiomyopathy are more likely to benefit from a biventricular assist device or a total artificial heart.

The role of bridge to transplantation: should LVAD patients be transplanted?

PURPOSE OF REVIEW

The decrease in useable donor organs means an increasing number of patients are requiring support with a left ventricular assist device (LVAD) for survival when their clinical status deteriorates before transplantation. We address whether these patients should be transplanted, if so, with what priority, and when and if they are not transplanted, what are the alternatives?

RECENT FINDINGS

The perioperative mortality and morbidity of LVAD insertion remains high. Infection and device failure still limit the safety of long periods of bridging and might necessitate earlier transplantation. Early results suggest that the smaller impeller pumps may be associated with a lower incidence of device failure and infection, but with more thromboembolic and hemorrhagic complications. Transplantation of LVAD patients results in survival rates as good as those with conventional transplantation, and the survival benefit is better than for non-LVAD-supported patients. A small number of LVAD patients have shown a significant improvement in myocardial function, sufficient enough to allow explantation of the device. The proportion of these patients has previously been reported to be as low as 5%, but a strategy to maximize recovery has allowed pump removal in approximately two thirds of dilated cardiomyopathy patients. In a recent destination therapy trial, survival in LVAD patients was superior to those on medical therapy, but the frequency of infection, bleeding, and malfunction of the device was higher.

SUMMARY

LVAD technology is continuing to evolve quickly, while transplantation is here to stay. The interaction between these two powerful modalities requires continued thoughtful evaluation for maximal benefit to patients.

Patient Selection for Left Ventricular Assist Devices

The use of mechanical support as a bridge to cardiac transplant has become the standard of care in many cardiac transplant centers. This therapy has been shown to increase survival and improve morbidity in carefully selected patients waiting for heart transplantation. With approximately 30000 patients being listed worldwide for transplant every year and only 3500 transplantations performed annually, alternative strategies need to be developed to minimize morbidity and mortality in this high-risk population. Patient selection remains the primary determinant of success with left ventricular assist device (LVAD) therapy. This article will review both the cardiac and extracardiac considerations needed in the assessment of patient suitability for LVAD support as a bridge to transplantation.

A strategy of hypothermic circulatory arrest for difficult heart transplant postventricular assist device

Donor heart and ventricular assist device excision can be extremely difficult at the time of heart transplant. We present a strategy of hypothermic circulatory arrest established with ventricular assist device cannulas for difficult heart transplants. The device inlet or outlet cannulas already in place, or both, are used to complement the safe cannulation sites available. This approach permits controlled excision of the recipient heart and device, easy access to convert to standard ascending aorta and bicaval cannulation, and minimizes the donor graft anoxia time. Two case reports are presented.

Insertion of a left ventricular assist device in patients without thorough transplant evaluations: a worthwhile risk?

OBJECTIVES

Patients in acute cardiogenic shock may require placement of left ventricular assist devices before undergoing standard pretransplant evaluations. This practice raises ethical and logistic concerns and has led us to investigate the short- and long-term outcomes for this patient population. Methods and results We examined our adult bridge-to-transplant left ventricular assist device population over a 6-year period to characterize those patients with acute cardiogenic shock who received left ventricular assist devices on an emergency basis (ie, placement of a device within 24 hours of being listed for cardiac transplantation). Outcomes before and after transplant were compared with those of candidates with nonemergency evaluations by Kaplan-Meier survival curves and the Fisher exact test where appropriate. Of the 115 patients who required left ventricular assist device support, 73 (63%) patients required emergency placement; 70% of these patients survived to transplant compared with 83% of those with nonurgent device implantation (not statistically significant). Posttransplant survival curves were similar for patients with emergency device placement and those with nonurgent placement (not statistically significant). Twenty-two patients having emergency device placement did not undergo heart transplantation because of multisystem organ failure (14), device support withdrawal from irreversible neurologic injury (4), device or technical problems (2), and left ventricular assist device explant due to myocardial recovery (2).

CONCLUSIONS

At our institution, the majority of left ventricular assist devices are placed on an emergency basis. Few of these patients require discontinuation of device support due to undetected conditions during abbreviated preoperative evaluation. Survival before and after transplant is comparable with those of patients who undergo nonurgent left ventricular assist device placement or medical therapy.

Patient selection for the use of ventricular assist devices as a bridge to transplantation

Patient selection is a critical factor in the outcome associated with the use of mechanical assist devices for the treatment of refractory heart failure/shock. Numerous risk factors impact on the outcome, many of which can be identified and treated before device surgery. This manuscript reviews all the risk factors that have been identified to date and the use of composite risk scores to predict outcome.

Development of a database of patients supported by ventricular assist devices

An increase in the number of patients with end stage heart failure is leading to increased use of ventricular assist devices (VAD). However, sometimes the optimal time point for implantation of left ventricular or biventricular support remains unclear. Data analysis using an electronic database may help to make the decision making process more precise and thus improve outcome. However, it is not easy to find a balance between sufficient comprehensiveness of the data, which are selected from a huge amount of available information, and practicability of database maintenance and data analysis. We developed the Assist Database based on Access for Windows. The Assist Database consists of five main parts: (1) demographic and admission data, diagnosis, goal, and type of VAD; (2) preoperative period; (3) postoperative period up to 30 days; (4) follow-up period; and (5) statistical evaluation. The preoperative and postoperative parts include hemodynamic data; ventilatory support; laboratory results; results from echocardiographic, neurologic, pathologic, and other examinations; medication; and complications. The follow-up part documents readmissions, complications, and outcome. From April 1987 to October 2002, eight different types of VAD were implanted in 654 patients in our institution. Their data were retrospectively added to the Assist Database using medical records and different previously used electronic databases. Since the Assist Database came into routine use, it has been supplied daily with selected data of current patients. On the data entry level, the data arising from medical records are entered either manually via standard forms or automatically from other electronic documentation systems used in our hospital in routine patient care to collect laboratory results, demographic data, blood transfusion data, and operative data and from electronic patient charts via interfaces. The structure of the database is designed to facilitate the data analysis level. The database presented is one of three databases united to form a network. The structure of the Assist Database facilitates comprehensive, time saving data collection, which allows different online data analyses. These analyses may affect the decision making process and thus improve outcome. However, achieving a balance between the volume of available information, the time consumed, and the relevance of the data for further analysis remains difficult. The Assist Database should include information relevant for the decision making process and for the prediction of outcome. In particular, data collection should be focused on patients' preoperative condition and on postoperative organ function and quality of life. Further, different databases (for patients with congestive heart failure, assist device patients, and transplanted patients) should be unified to form a network to avoid the repeated collection of identical data, to save time, and to increase the quality of analysis. In the long-term, multicenter use of the Assist Database could be considered.

Differential gene expression and genomic patient stratification following left ventricular assist device support

OBJECTIVES

We sought to determine whether mechanical unloading of the failing human heart with a left ventricular assist device (LVAD) results in significant changes in overall left ventricular gene expression.

BACKGROUND

Mechanical circulatory support by LVAD in end-stage human heart failure (HF) can result in beneficial reverse remodeling of myocardial structure and function. The molecular mechanisms behind this salutary process are not well understood.

METHODS

Left ventricular samples from six male patients were harvested during LVAD placement and subsequently at the time of explantation. Cardiac gene expression was determined using oligonucleotide microarrays.

RESULTS

Paired t test analysis revealed numerous genes that were regulated in a statistically significant fashion, including the downregulation of several previously studied genes. Further statistical analysis revealed that the overall gene expression profiles could significantly distinguish pre- and post-LVAD status. Interestingly, the data also identified two distinct groups among the pre-LVAD failing hearts, in which there was blind segregation of patients based on HF etiology. In addition to the substantial divergence in genomic profiles for these two HF groups, there were significant differences in their corresponding LVAD-mediated regulation of gene expression.

CONCLUSIONS

Support with an LVAD in HF induces significant changes in myocardial gene expression, as pre- and post-LVAD hearts demonstrate significantly distinct genomic footprints. Thus, reverse remodeling is associated with a specific pattern of gene expression. Moreover, we found that deoxyribonucleic acid microarray technology could distinguish, in a blind manner, patients with different HF etiologies. Expansion of this study and further development of these statistical methods may facilitate prognostic prediction of the individual patient response to LVAD support.