Importance of preoperative liver function as a predictor of survival in patients supported with Thoratec ventricular assist devices as a bridge to transplantation

Preoperative Liver Function Test Abnormalities Were Associated With Short-Term and Long-Term Prognosis in Cardiac Surgery Patients Without Liver Disease

Aims: To explore the value of preoperative liver function tests (LFTs) for the prognosis of cardiac surgery patients without liver disease.

Methods: The Medical Information Mart for Intensive Care III (MIMIC-III) database was used to extract the clinical data. Adult cardiac patients (≥18 years) without liver disease in the database were enrolled. The association of LFTs with the time of hospital stay and ICU stay was analyzed with the Spearman correlation. Survival curves were estimated using the Kaplan-Meier method and compared by the log-rank test. Multivariable logistic regression was used to identify LFTs that were independent prognostic factors of mortality.

Results: A total of 2,565 patients were enrolled in this study. Albumin (ALB) was negatively associated with the time of hospital stay and ICU stay, while alanine transaminase (ALT), aspartate aminotransferase (AST), and total bilirubin were positively associated with the time of hospital stay and ICU stay (all p < 0.001). Abnormal ALB, ALT, AST, and total bilirubin were associated with lower 90-day and 4-year survival (all p < 0.001) and could be used as independent risk factors for hospital mortality and 90-day mortality. However, only ALB and total bilirubin were independent risk factors for 4-year mortality.

Conclusion: Preoperative LFT abnormalities were associated with short-term and long-term prognosis of cardiac surgery patients without liver disease.

The prevalence and prognostic implications of pre-procedural hyperbilirubinemia in patients undergoing transcatheter aortic valve replacement

Preoperative hyperbilirubinemia is associated with increased mortality and morbidity after cardiac surgery. However, this clinical significance is unclear with transcatheter aortic valve replacement (TAVR) procedures. The aims of this study were to determine the prevalence and prognostic implications of preoperative elevations of serum total bilirubin on TAVR outcomes. In 611 consecutive patients who underwent an elective TAVR procedure, 576 patients had recorded serum total bilirubin levels. Hyperbilirubinemia was defined as any value of serum total bilirubin ≥ 1.2 mg/dL obtained within 30-days prior to the TAVR procedure. The primary composite endpoint was post-TAVR all-cause in-hospital mortality or stroke. The overall prevalence of hyperbilirubinemia was 10% (n = 58). There were no patients with a prespecified diagnosis of liver cirrhosis. Pre-TAVR hyperbilirubinemia compared to normal bilirubin level was more common in younger (78 ± 10 vs. 82 ± 8 years old, p < 0.001) males (15 vs. 6%, p < 0.001), with history of pacemaker or ICD (33 vs. 18%, p = 0.005), congestive heart failure New York Heart Association class IV within 2 weeks from TAVR (35 vs. 14%, p < 0.001), severe tricuspid regurgitation (14 vs. 4%, p < 0.001), and atrial fibrillation or flutter (60 vs. 40%, p = 0.004, respectively). Pre-TAVR hyperbilirubinemia was independently associated with an increased post-TAVR in-hospital mortality (7 vs. 2% in normal bilirubin, p = 0.03), stroke (5 vs. 1%, p = 0.019, respectively), and a composite endpoint of death or stroke (12 vs. 3%, p < 0.001). Preoperative hyperbilirubinemia in patients undergoing TAVR is more prevalent than previously considered with multifactorial causes. Hyperbilirubinemia is independently associated with an increased post-TAVR in-hospital mortality and stroke.

Evolution of association between renal and liver functions while awaiting heart transplant: An application using a bivariate multiphase nonlinear mixed effects model

In many longitudinal follow-up studies, we observe more than one longitudinal outcome. Impaired renal and liver functions are indicators of poor clinical outcomes for patients who are on mechanical circulatory support and awaiting heart transplant. Hence, monitoring organ functions while waiting for heart transplant is an integral part of patient management. Longitudinal measurements of bilirubin can be used as a marker for liver function and glomerular filtration rate for renal function. We derive an approximation to evolution of association between these two organ functions using a bivariate nonlinear mixed effects model for continuous longitudinal measurements, where the two submodels are linked by a common distribution of time-dependent latent variables and a common distribution of measurement errors.

Association of direct bilirubin level with postoperative outcome in critically ill postoperative patients

Background

Hyperbilirubinemia is a common postoperative complication. Elevated direct bilirubin (D-Bil) and indirect bilirubin (I-Bil) levels are related to different pathophysiologies; therefore, their associations with outcomes also differ. However, there have been few comparative studies of such associations in postoperative patients.

Methods

This retrospective study compared the associations of postoperative D-Bil and I-Bil with outcomes. We included adult patients requiring postoperative intensive care for more than 48 hours between 2008 and 2013, except those undergoing liver operations. The number of patients was determined using a power calculation. D-Bil and I-Bil measurements were obtained on postoperative days (POD) 1 and 2. The primary outcome was defined as hospital mortality, with the number of ICU-free survival days (IFSD) at POD 28 as the secondary outcome.

Results

The study population consisted of 1,903 patients with a mortality rate of 2.2%. D-Bil at POD 1 was significantly higher in non-survivors than survivors (P = 0.001), but I-Bil at POD 1 showed no such relation (P = 0.209). Multivariate logistic analysis indicated that higher postoperative D-Bil was independently associated with increased postoperative mortality (POD 1: adjusted odds ratio [OR] = 2.32, P < 0.001; POD 2: adjusted OR = 1.95, P < 0.001), but I-Bil showed no such relation (POD 1: P = 0.913; POD 2: P = 0.209). Increased D-Bil was independently associated with decreased IFSD at POD 28 (POD 1: adjusted coefficient = -1.54, P < 0.001; POD 2: -1.84, P < 0.001). In contrast, increased I-Bil at POD 1 was independently associated with increased IFSD at POD 28 (POD 1: adjusted coefficient = +0.39, P = 0.021; POD 2: +0.33, P = 0.080).

Conclusions

D-Bil indices have a higher capability than I-Bil for predicting poorer outcomes in critically ill postoperative patients.

Diagnosis and Management of Noncardiac Complications in Adults With Congenital Heart Disease: A Scientific Statement From the American Heart Association

Life expectancy and quality of life for those born with congenital heart disease (CHD) have greatly improved over the past 3 decades. While representing a great advance for these patients, who have been able to move from childhood to successful adult lives in increasing numbers, this development has resulted in an epidemiological shift and a generation of patients who are at risk of developing chronic multisystem disease in adulthood. Noncardiac complications significantly contribute to the morbidity and mortality of adults with CHD. Reduced survival has been documented in patients with CHD with renal dysfunction, restrictive lung disease, anemia, and cirrhosis. Furthermore, as this population ages, atherosclerotic cardiovascular disease and its risk factors are becoming increasingly prevalent. Disorders of psychosocial and cognitive development are key factors affecting the quality of life of these individuals. It is incumbent on physicians who care for patients with CHD to be mindful of the effects that disease of organs other than the heart may have on the well-being of adults with CHD. Further research is needed to understand how these noncardiac complications may affect the long-term outcome in these patients and what modifiable factors can be targeted for preventive intervention.

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.

Short-Term Experience with Off-Pump Versus On-Pump Implantation of the HeartWare Left Ventricular Assist Device

Implantation of left ventricular assist devices while avoiding cardiopulmonary bypass (CPB) may decrease bleeding and improve postoperative recovery. To understand the effectiveness of this approach, we reviewed the charts of 26 patients who underwent HeartWare left ventricular assist device (HVAD) implantation without use of CPB (off-CPB group) and 22 patients who had HVAD implanted with CPB (CPB group) with an emphasis on the 30 day postoperative period. Preoperatively, both groups had similar demographic, functional, and hemodynamic characteristics. Off-CPB patients had significantly shorter surgery times than CPB patients, 188.5 (161.5-213.3) min versus 265.0 (247.5-299.5) min, respectively; p < 0.001. Blood transfusion requirements during surgery and within the postoperative 48 hour period were significantly lower in the off-CPB group than in the CPB group (odds ratio: 5.9; 95% confidence interval: 1.1-31.1, p = 0.042). Compared with the CPB group, the off-CPB group patients had a shorter intubation time, 21 (17.4-48.5) hours versus 41 (20.6-258.4) hours; p = 0.042. Intensive care unit stay was 7.0 (4.75-13.5) days for off-CPB versus 10.0 (6.0-19.0) days for CPB (p = 0.256). The off-CPB approach allows HVAD to be implanted quickly with significantly less perioperative bleeding and transfusion requirements and facilitates postoperative rehabilitation.

Successful treatment of near-fatal fulminant myocarditis using bi-ventricular assist device support

Fulminant myocarditis is a rare but fatal serious disease that may cause prolonged native cardiac dysfunction with multiorgan failure despite temporary mechanical circulatory support with percutaneous venoatrial extracorporeal membrane oxygenation (VA-ECMO) or intraaortic balloon pumping (IABP). A 26-year-old man with fulminant myocarditis developed life-threatening multiorgan failure after 8 days support by VA-ECMO and IABP. He was transferred to our institution with prolonged cardiac dysfunction on hospital day 8; massive pulmonary edema developed into severe pulmonary dysfunction. Immediately after admission, VA-ECMO and IABP were switched to a paracorporeal pneumatic left ventricular assist device (LVAD) and right centrifugal ventricular assist device with an ECMO circuit shunting from the right ventricle to the pulmonary artery (RVAD-ECMO). After intensive care focusing on respiratory dysfunction, ECMO was successfully weaned, and the right ventricular assist device was switched to a durable paracorporeal pneumatic right ventricular assist device. The paracorporeal bi-ventricular assist devices were finally replaced with an implantable non-pulsatile LVAD on hospital day 181. Currently, 1 year after discharge, the patient is at home awaiting heart transplantation. Combined LVAD and RVAD-ECMO appear to be useful for resolving severe pulmonary edema due to unnecessarily long VA-ECMO support as well as kidney or liver dysfunction caused by circulatory collapse.

Liver stiffness measurements and short-term survival after left ventricular assist device implantation: A pilot study

BACKGROUND

Hepatic dysfunction can contribute to the clinical outcome of patients with end-stage chronic heart failure (HF). This pilot study evaluated the importance of liver stiffness (LS) measurements by acoustic radiation force impulse (ARFI) imaging elastography in patients with end-stage chronic HF who underwent left ventricular assist device (LVAD) implantation.

METHODS

The study enrolled 28 patients (23 men), mean age of 54 ± 11 years, with end-stage chronic HF selected for LVAD implantation. At baseline, all patients received LS measurements using ARFI elastography. Hepatic venous pressure gradient measurements and transjugular liver biopsies were performed in 16 patients. Liver stiffness was measured 21 days (Follow-up 1, n = 23) and 485 ± 136 days (Follow-up 2, n = 13) after LVAD implantation. Patients were classified according to their baseline LS into Group I (low baseline LS [no significant fibrosis = Metavir F < 2]) or Group II (high baseline LS [significant fibrosis = Metavir F ≥ 2]).

RESULTS

LS at baseline was higher in Group II than in Group I (p < 0.001) and decreased significantly after LVAD implantation (Follow-up 1, p = 0.002; Follow-up 2, p = 0.002). Baseline LS correlated with liver fibrosis (p = 0.049) and central venous pressure (p = 0.001). Non-survivors showed higher LS (p = 0.019), bilirubin (p = 0.018), Model for End-Stage Liver Disease score (p = 0.001), and liver fibrosis (p = 0.004) compared with the survivors. In the univariate analysis, LS was a significant factor (p = 0.017) in predicting survival after LVAD implantation.

CONCLUSIONS

ARFI elastography shows that LS is influenced by central venous congestion and histologic changes of the liver in patients with end-stage chronic HF. LS may predict the outcome in patients after LVAD implantation.

Association of Serum Bilirubin with Stroke Severity and Clinical Outcomes

Objective:

The aim of the study is to explore the association of serum bilirubin levels with admission severity and short term clinical outcomes among acute ischemic stroke patients.

Methods:

Data were collected from 2361 acute ischemic stroke patients in four hospitals of Shangdong Province during January 2006 and December 2008. National Institutes of Health Stroke Scale (NIHSS) was used to assess admission and discharge severity. NIHSS≥10 at discharge or in-hospital death was defined as short-term clinical outcomes. Logistic regression and trend test were used to examine the association of serum bilirubin levels with admission severity and short term clinical outcomes.

Results:

Serum bilirubin levels were significantly and positively associated with admission severity (P for trend <0.05). The age-sex adjusted odds ratios (95% confidential intervals) of NIHSS≥10 associated with the second, third and fourth quartile of total bilirubin/direct bilirubin were 1.245 (0.873, 1.777)/1.276 (0.895, 1.818), 1.484 (1.048, 2.102)/1.628 (1.158, 2.289) and 2.869 (2.076, 3.966)/2.765 (1.996, 3.828), respectively, compared with the lowest quartile; the multivariate adjusted odds ratios of NIHSS≥10 associated with the second, third and fourth quartile of total bilirubin/direct bilirubin were 1.088(0.711, 1.665)/1.436(0.94, 2.193), 1.328(0.877, 2.011)/1.647(1.092, 2.485) and 2.336(1.579, 3.458)/3.079 (2.049, 4.623), respectively, compared with the lowest quartile. However, no association between serum bilirubin levels and short-term clinical outcomes was observed in our study.

Conclusion:

Serum bilirubin levels were associated with initial stroke severity closely. Nevertheless, there is no significant relationship between serum bilirubin levels and short-term clinical outcomes among acute ischemic stroke patients.

Extracorporeal life support as a bridge to high-urgency heart transplantation

Extracorporeal life support (ECLS) represents an effective, emergent therapy for patients with end-stage heart failure or cardiac arrest. However, ECLS is typically not used as a bridge to heart transplantation because of the limited duration of ECLS. In France, high-urgency priority heart transplantation remains a possibility for transplant patients who are on ECLS. In this article, we present our experience with high-urgency priority heart transplantation after ECLS. From July 2004 to December 2009, 242 patients underwent emergent ECLS. Heart transplantation was performed in eight of these patients. Time of ECLS was 6.3 ± 4.6 d. Before heart transplantation, all patients on ECLS had decreased organ dysfunctions and four were conscious. Despite frequent post-operative complications, no death occurred during the first year after transplantation. In our experience, ECLS is a valid method of supporting patients awaiting high-urgency heart transplantation and can be used as a short-term bridge to heart transplantation.

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 in patients with liver cirrhosis undergoing cardiovascular operations

BACKGROUND

Variable outcomes of cardiac operations have been reported in cirrhotic patients, but no definitive predictive prognostic factors have been established. This retrospective study assessed operative results to identify risk factors associated with morbidity after cardiovascular operations in cirrhotic patients.

METHODS

The study comprised 42 cirrhotic patients who underwent cardiovascular operations from January 1991 to January 2009. Thirty patients were Child-Turcotte-Pugh class A, and 12 were class B. Hospital morbidity occurred in 13 patients (31.0%; M group), including 4 who died in-hospital. Patients without severe complications (N group) were compared with the M group patients. The Model for End-Stage Liver Disease (MELD) score was evaluated in 25 patients.

RESULTS

Significant differences in hospital morbidity between the M vs N groups were identified for platelet count (8.7 +/- 3.8 vs 12.1 +/- 4.2 x 10(4)/microL), MELD score (17.8 +/- 5.3 vs 9.8 +/- 4.9), operation time (370 +/- 88 vs 313 +/- 94 minutes), and cardiopulmonary bypass time (174 +/- 46 vs 149 +/- 53 minutes) in univariate analyses (p < 0.005). Platelet count, operation time, and age were significantly associated with hospital morbidity in multivariate analyses (p < 0.005). Platelet count of 9.6 x 10(4)/microL and MELD score of 13 were cutoff values for hospital morbidity.

CONCLUSIONS

Careful consideration of operative indications and methods are necessary in cirrhotic patients with low platelet counts or high MELD scores. A high incidence of hospital morbidity is predicted in patients with platelet counts of less than 9.6 x 10(4)/microL or MELD scores exceeding 13.

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.

Association of serum bilirubin with ischemic stroke outcomes

BACKGROUND

Higher levels of serum bilirubin may offer a therapeutic advantage in oxidative stress-mediated diseases, but may also simply reflect intensity of oxidative stress. Little is known about the role of bilirubin in stroke. We assessed the relation of serum bilirubin levels with clinical presentation and outcomes among patients hospitalized with ischemic stroke.

METHODS

Data were collected prospectively during a 5-year period on consecutive ischemic stroke admissions to a university hospital. Serum bilirubin levels, total (Tbil) and direct (Dbil), were measured on admission. Presenting stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS). Functional outcome at discharge was assessed using the modified Rankin scale.

RESULTS

Among 743 patients, mean age was 67.3 years and 47.5% were women. Median presenting NIHSS score was 4, and 24% had a poor (modified Rankin scale 4-6) functional outcome at discharge. Higher Dbil levels were associated with greater stroke severity (P = .001) and poorer discharge outcome (P = .034). Multivariable regression analyses showed that those with higher Dbil levels (> or =0.4 mg/dL) had significantly greater admission NIHSS scores compared with those with lower levels (< or =0.1 mg/dL) (odds ratio 2.79, 95% confidence interval 1.25-6.20, P = .012), but no independent relationship was confirmed between Dbil and discharge outcome. Although higher admission Tbil was associated with greater stroke severity in crude analyses (P = .003), no independent relationship between Tbil versus stroke severity or outcome was noted after adjusting for confounders.

CONCLUSIONS

Higher Dbil level is associated with greater stroke severity but not outcome among ischemic stroke patients, possibly reflecting the intensity of initial oxidative stress. Further study into the underlying pathophysiology of this relationship is needed.

Assessment of transcutaneous bilirubinometry in hospitalized adults

BACKGROUND

Transcutaneous techniques to measure serum bilirubin have been validated in neonates but not in adult patients. We evaluated transcutaneous bilirubinometry (TcB) in adults at risk for or diagnosed with hepatic dysfunction to determine if this technology has clinical use in quantifying the presence and magnitude of hyperbilirubinemia.

DESIGN

Unblinded, consecutive hospitalized adult patients (n = 80) from the general surgery, trauma surgery, and liver resection/transplantation services of a tertiary care, university-affiliated medical center, who were having serum bilirubin measurements performed, underwent transcutaneous bilirubin measurement from the forehead, sternum, forearm, and deltoid. Transcutaneous bilirubin measurements were repeated each time serum bilirubin measurements were performed.

RESULTS

Transcutaneous bilirubin measurements from the forehead correlated with serum bilirubin better (r, 0.963) than measurements from the forearm (r, 0.792), deltoid (r, 0.922), or sternum (r, 0.928). Forehead TcB detected hepatic dysfunction (serum bilirubin > or = 2 mg/dL) by receiver operator curves (area under the curve = 0.971) and sternum (area under the curve = 0.970) and better than deltoid and forearm measurements (area under the curve = 0.935 and 0.893, respectively). A Bland-Altman plot demonstrated that forehead measurements became less accurate as the magnitude of hyperbilirubinemia increased.

CONCLUSIONS

Forehead TcB correlated best with serum bilirubin levels but became less accurate at higher values. Refinements in the technology will be required before this technique, although promising, can be considered for routine clinical application in adults being evaluated for hyperbilirubinemia.

Emergency cardiac mechanical assistance: place of mucosal gastric tonometry as prognostic indicator

BACKGROUND AND OBJECTIVES

The death of patients treated by ventricular assist device is usually related to multiorgan failure for which a disorder of splanchnic circulation is blamed. Gastric tonometry (measurement of gastric intra-mucosal pressure of CO(2)) has already been studied in many fields and especially in cardiac surgery. The aim of this study was to investigate the prognostic value of gastric tonometry monitoring after implantation of a ventricular assist device.

METHODS

In this prospective study, all consecutive patients scheduled for a ventricular assist device were included. Gastric tonometry was added to standard monitoring. Data were collected (lactate, gastric CO(2) (PgCO(2)) during cardiopulmonary bypass, at admission to ICU, 24 and 48 h later and when norepinephrine was stopped. Preoperative biologic and haemodynamic data were also collected. The primary endpoint was death.

RESULTS

Fifty-six patients (50 men and 6 women) were included. In 91% of the cases, the mechanical assistance was biventricular. The objective of the assistance was a bridge to transplant in 93% (n = 27). Twenty-seven deaths (48%) occurred during the study, 59% (n = 16) of them took place before the cardiac transplantation (mean time = 18 +/- 16 days after assist device insertion). Many factors were found to be associated with death: weight (P = 0.018), red cells administration (P = 0.025), length of surgery (P = 0.016), PgCO(2) on admission to ICU (P = 0.040) and norepinephrine dose at 24 h.

CONCLUSIONS

Gastric tonometry has a prognostic value in the early postoperative hours after the implantation of a ventricular assist device.

Open-heart surgery in patients with liver cirrhosis: indications, risk factors, and clinical outcomes

BACKGROUND

Because of recent advances in cardiopulmonary bypass (CPB) surgery, there are broadened indications to approach patients with a high operative risk. Meanwhile, there is an increasing number of patients with severe liver dysfunction subjected to open-heart surgery. This retrospective study was designed to evaluate the operative indications and clinical outcomes in patients with liver cirrhosis (LC) undergoing open-heart surgery. In addition, determinants influencing their prognosis were assessed.

PATIENTS AND METHODS

Between May 1996 and June 2005, 24 patients with LC underwent CPB open-heart surgery in our institution. The preoperative severity of the LC was determined according to the Child-Pugh classification. Their perioperative data were analyzed. Several perioperative factors were compared by multivariate logistic regression analysis between survivors and nonsurvivors to determine possible risk factors contributing to mortality.

RESULTS

There were 14 females and 10 males. Their age ranged from 36 to 72 (mean 53 +/- 13) years. Seventeen cases were classified as having Child-Pugh class A LC, 6 as having Child-Pugh class B, and 1 as having Child-Pugh class C LC. All patients underwent CPB surgery. The mean operation time and the cross-clamp time were 160 +/- 53 and 90 +/- 42 min, respectively. During the first 24 h after the operation, the mean chest tube output was 1,080 +/- 320 ml. The mean duration of mechanical ventilation was 32 +/- 22 h, and the mean intensive care unit stay was 11 +/- 8 days. Sixty-six percent of the patients experienced significant morbidity. Fifty-three percent of the patients with Child-Pugh class A LC and 100% of those with Child-Pugh class B and C LC suffered postoperative complications. The overall mortality rate was 25%. The postoperative mortality rates of the patients with Child-Pugh class A, B, and C LC were 6, 67, and 100%, respectively. Preoperative serum total bilirubin and cholinesterase levels and EuroSCORE (European System for Cardiac Operative Risk Evaluation) values along with CPB time were identified as the important predictors to differentiate between survivors and nonsurvivors by multivariate logistic regression analysis.

CONCLUSIONS

The Child-Pugh class is associated with hepatic decompensation and mortality after open-heart CPB surgery in patients with LC. Such surgery can be performed safely in patients with a Child-Pugh class A LC. But cardiac interventions using CPB in patients with more advanced LC are associated with high mortality and morbidity rates. The preoperative total plasma bilirubin and cholinesterase concentrations as well as the EuroSCORE along with the CPB time are identified as statistically significant predictors of mortality after open-heart surgery in patients with LC. Our findings indicate that patients with chronic liver disease scheduled for open-heart surgery should be carefully evaluated before the operation and that the CPB duration should be as short as possible.

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.

Right ventricular failure after left ventricular assist device implantation: the need for an implantable right ventricular assist device

Right ventricular failure after implantation of a left ventricular assist device is an unremitting problem. Consideration of portal circulation is important for reversing liver dysfunction and preventing multiple organ failure after left ventricular assist device implantation. To achieve these objectives, it is imperative to maintain the central venous pressure as low as possible. A more positive application of right ventricular assistance is recommended. Implantable pulsatile left ventricular assist devices cannot be used as a right ventricular assist device because of their structure and device size. To improve future prospects, it is necessary to develop an implantable right ventricular assist device based on a rotary blood pump.

Clinical outcome after cardiac operations in patients with cirrhosis

BACKGROUND

To evaluate the clinical outcome after cardiac operations in patients with cirrhosis, a retrospective study was undertaken.

METHODS

Between 1989 and 2003, 18 patients with cirrhosis who underwent cardiac operations were identified. Their preoperative status and postoperative clinical results were assessed.

RESULTS

Ten patients were classified as having Child-Pugh class A cirrhosis, 7 as having class B cirrhosis, and 1 as having class C cirrhosis. Fifteen of 18 patients underwent cardiac surgery using cardiopulmonary bypass, and the remaining 3 patients with class B cirrhosis received coronary artery bypass grafting without cardiopulmonary bypass. In patients undergoing cardiopulmonary bypass, 60% of those with class A cirrhosis and 100% of those with class B cirrhosis and class C cirrhosis had postoperative major complications, including infection, respiratory failure, renal failure, bleeding, and gastrointestinal disorder. One of 3 patients (33%) with class B cirrhosis undergoing coronary artery bypass grafting without cardiopulmonary bypass had major complications. The overall postoperative mortality rate was 17%. Hospital mortality of patients with class A cirrhosis, class B cirrhosis, and class C cirrhosis undergoing cardiopulmonary bypass was 0%, 50%, and 100%, respectively. None of 3 patients with class B cirrhosis undergoing coronary artery bypass grafting without cardiopulmonary bypass died in this study.

CONCLUSIONS

Although the incidence of major complications was high, patients with Child-Pugh class A cirrhosis tolerated cardiac surgery satisfactorily. Patients with more advanced cirrhosis, however, may not be suitable for elective cardiac operations with cardiopulmonary bypass. Although our results are not conclusive, coronary artery bypass grafting without cardiopulmonary bypass can be an alternative therapeutic strategy for patients with advanced cirrhosis requiring surgical revascularization.

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.

The use of extracorporeal life support in adult patients with primary cardiac failure as a bridge to implantable left ventricular assist device

BACKGROUND

Extracorporeal life support (ECLS) is an effective technique for providing emergent circulatory assistance, and may represent a life-saving option in patients who might not initially be considered a candidate for other forms of circulatory support (extracorporeal or implantable left ventricular assist device [LVAD]). In the setting of cardiac arrest, ECLS represents the only viable method of initiating circulatory support. However, ECLS has a number of disadvantages that include high complication rates (eg, stroke, bleeding) and a limited duration of potential support, which have prevented its widespread acceptance, particularly in the adult population. With the increased successful application of long-term implantable LVADs as a bridge to transplant, the major limitation of ECLS could be overcome by bridging patients to a long-term implantable LVAD ("bridge to bridge"), thereby reducing the reluctance to utilize ECLS when indicated. After acquisition of the HeartMate LVAD (Thermo Cardiosystems, Inc, Woburn, MA) we investigated the use of ECLS as a bridge to an implantable LVAD and subsequent transplantation in selected high-risk patients.

METHODS AND RESULTS

From Oct 1, 1996 to Sept 30, 2000, 33 adult patients presenting with cardiac arrest or severe hemodynamic instability were placed on ECLS for the bridge to bridge indication. Of the 33 patients, 10 patients survived to LVAD implant, 1 was bridged directly to transplant, 5 weaned from ECLS, and 16 died on ECLS. Overall, 12 patients survived to discharge. One-year actuarial survival from the initiation of ECLS was 36%. One-year actuarial survival from the time of LVAD implant, conditional on surviving ECLS, was 80%.

CONCLUSIONS

The 1-year survival of adult patients placed on ECLS and who subsequently survived to an implantable LVAD was favorable. These data support a strategy of ECLS to implantable LVAD bridge to heart transplant in adult patients who are in need of circulatory support and who are not initially candidates for other forms of mechanical support. The favorable results of this strategy support utilization of ECLS even in situations where myocardial recovery is thought to be unlikely.

Indications and patient selection for mechanical ventricular assistance

Cardiac assist devices have become an important component of transplantation programs as they successfully bridge unsalvageable patients who would otherwise die. The indications for a device can still be classified into short-term and long-term situations. The short-term indications have expanded into areas such as postcardiotomy failure, high-risk cardiac operations, and acute myocardial infarction with results that were not previously possible in the absence of a well-established mechanical assistance program. Appropriate patient selection remains challenging and perhaps the most important attribute of a successful ventricular assist program. Although few exact criteria can define patients who are not eligible, several considerations and screening scales can help determine a particular patient's suitability. Specific attention must be given to right heart function, neurologic status, existing infections, renal function, and transplantation suitability. The future of this field will not only be in technological advances with devices but in optimization of patient selection and expanding indications such as permanent replacement therapy.

Assessment of an extracorporeal life support to LVAD bridge to heart transplant strategy

BACKGROUND

Extracorporeal life support (ECLS) is an effective technique for providing emergent circulatory assistance. However, its use in adult patients is associated with poor survival when myocardial function fails to recover. Due to the prolonged waiting times for heart transplantation, ECLS as a bridge to transplant is associated with poor survival. In addition, ECLS has been reported to be a significant risk factor for death after bridging to an implantable left ventricular assist device (LVAD). After acquisition of the HeartMate LVAD (Thermo Cardiosystems, Inc) in October 1996, we began using ECLS as a bridge to an implantable LVAD and subsequently transplantation in selected high-risk patients.

METHODS

From October 1, 1996 to December 1, 1999, 60 adult patients presenting with cardiogenic shock were evaluated for circulatory assistance.

RESULTS

Twenty-five patients (group 1) with cardiac arrest or severe hemodynamic instability and multiorgan failure were placed on ECLS. Eight patients survived to LVAD implant, 1 was bridged directly to transplant, and 4 weaned from ECLS. Nine patients in group 1 survived to discharge. Thirty patients (group 2) underwent LVAD implant without ECLS. Twenty-three were bridged to transplant, with 22 surviving to discharge. Five patients (group 3) were placed on extracorporeal ventricular assist with 3 bridged to transplant and all surviving to discharge. One-year actuarial survival from the initiation of circulatory support was 36% (group 1), 73% (group 2), and 60% (group 3). One-year actuarial survival from the time of LVAD implant in group 1, conditional on surviving ECLS, was 75% (p = NS compared with group 2).

CONCLUSIONS

In selected high-risk patients, LVAD survival after initial ECLS was not different from survival after LVAD support alone. An initial period of resuscitation with ECLS is an effective strategy to salvage patients with cardiac arrest or extreme hemodynamic instability and multiorgan injury.

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

BACKGROUND

Careful patient selection markedly influences the outcome of patients who undergo mechanical circulatory support. Therefore, we tried to evaluate predictors of survival after implantation of the Thoratec ventricular assist device (VAD).

METHODS

Between October 1992 and January 2000, 104 patients (86 men, 18 women, aged 11 to 69 years) received the Thoratec VAD as a bridge to transplant. A total of 51 patients required left ventricular support (LVAD), 50 patients required biventricular support (BVAD), and 3 patients required total artificial heart implantation. We performed univariate analysis of 25 parameters with regard to their effect on survival and then applied a multivariate analysis to evaluate those factors that turned out to be marginally significant. We performed all analysis for the total collective as well as for the LVAD and BVAD sub-group.

RESULTS

The BVAD patients tended to have worse outcomes than did LVAD patients. We found no significant predictors of survival in either sub-group. In the total collective, however, we found the following pre-implant conditions were independent risk factors for survival after VAD implantation: patient age > 60 years (odds ratio [OR] 3.87, confidence interval [CI] 1.39 to 10.76), pre-implant ventilation (OR, 6.76; CI 2.42 to 18.84), and increased pre-implant total bilirubin (OR, 1.42; CL, 1.19 to 1.69).

CONCLUSIONS

Transplant candidates on inotropic support should be considered for bridging to transplant as soon as bilirubin values start to increase or before respiratory function deteriorates and ventilation becomes necessary. In elderly patients, careful patient selection, particularly considering potential risk factors, might favorably affect their outcomes.

The thoratec ventricular assist device: a paracorporeal pump for treating acute and chronic heart failure

The Thoratec Ventricular Assist Device (VAD) System (Thoratec Laboratories, Pleasanton, CA) is a paracorporeal pump that can provide univentricular or biventricular assistance for patients with heart failure. The system consists of a prosthetic ventricle that has a blood-pumping chamber of Thoralon (Thoratec Laboratories) polyurethane, cannulas for univentricular or biventricular support, and either a hospital-based pneumatic drive console or a portable battery-powered drive unit. For biventricular assistance, 2 pumps are used. The Thoratec voluntary registry indicates that, as of May 2000, this system had been implanted in 1,376 patients, mainly for bridging to transplantation (828 patients) or postcardiotomy support (195 patients); the remaining 353 patients received a hybrid configuration of the device or had incomplete information, so they are not included in this analysis. In the 828 bridge-to-transplant patients, the Thoratec system provided biventricular assistance in 472 cases, left ventricular assistance in 326 cases, and right ventricular assistance in 30 cases for up to 515 days. During the support period, the cardiac index increased significantly from 1.4 +/- 0.8 L/min/m2 to 3.0 +/- 0.5 L/min/m2 (with biventricular assistance and left ventricular cannulation). Sixty percent of the 828 patients underwent transplantation, and the posttransplant survival rate was 86%. In the 195 patients who needed postcardiotomy support, VADs were used for up to 80 days for cardiac recovery. Thirty-eight percent of the patients were weaned from the VAD, and 59% of the weaned group were discharged from the hospital. In addition, 49 postcardiotomy patients were considered for transplantation; of these, 32 received a transplant and 23 were discharged. Patient mobility is being improved by the use of a portable driver. The Thoratec VAD is suitable for a wide range of applications, and efforts are underway to facilitate patient mobility and allow hospital discharge. An intracorporeal version of the VAD, which is currently under development, will help achieve these goals.

Outcome of patients with ventricular assist devices and acute renal failure requiring renal replacement therapy

The significance of acute renal failure (ARF) for patients treated with a ventricular assist device (VAD) is uncertain. There is little information on the outcome of patients who require renal replacement therapy during treatment with a VAD. A retrospective review was undertaken to evaluate the impact of renal failure requiring renal replacement therapy on such patients. Studied were 227 patients who were supplied with a VAD at the German Heart Institute Berlin. Fifty-five patients required renal replacement therapy during treatment with a VAD. These were compared with patients not needing renal replacement therapy (ARF and non-ARF groups). Significant differences for the end points of survival, heart transplantation, and discharge from hospital were observed in patients with ARF (p < 0.01). Survival was then analyzed according to indications for treatment with a VAD (bridge to transplantation or cardiac recovery after cardiotomy, transplantation, myocardial infarction, myocarditis, and endocarditis). Survival for bridge-to-transplantation patients was clearly influenced in a negative way by ARF (p < 0.01). For cardiac recovery patients, only a small difference in survival was observed (p = 0.05). We conclude that ARF is a negative predictor for bridge-to-transplantation patients. For cardiac recovery patients the impact of ARF on survival is marginally significant.