Evaluation of cardiac manifestations in pediatric liver transplant candidates

Mechanistic insights into the pathophysiology of cirrhotic cardiomyopathy

Myocardial dysfunction in end stage cirrhotic liver disease, termed cirrhotic cardiomyopathy, is a long known, but little understood comorbidity seen in ∼50% of adults and children who present for liver transplantation. Structural, functional, hemodynamic and electrocardiographic aberrations that occur in the heart as a direct consequence of a damaged liver, is associated with multi-organ failure and increased mortality and morbidity in patients undergoing surgical procedures such as porto-systemic shunt placement and liver transplantation. Despite its clinical significance and rapid advances in science and pharmacotherapy, there is yet no specific treatment for this disease. This may be due to a lack of understanding of the pathogenesis and mechanisms behind how a cirrhotic liver causes cardiac pathology. This review will focus specifically on insights into the molecular mechanisms that drive this liver-heart interaction. Deeper understanding of the etio-pathogenesis of cirrhotic cardiomyopathy will allow us to design and test treatments that can be targeted to prevent and/or reverse this co-morbid consequence of liver failure and improve health care delivery and outcomes in patients with cirrhosis.

Evaluation of ventricular systolic function by speckle tracking technique in patients with biliary atresia before and after liver transplantation

To evaluate the ventricular function of patients with biliary atresia (BA) before and after liver transplantation using two-dimensional speckle tracking. Observational, analytical study with healthy control group, volunteers. We recruited patients from 0 to 18 years old who were candidates for liver transplantation and patients after six months of liver transplantation performed for BA from January 1997 to August 2015 at Children's Institute of São Paulo University Medical School. The patients were submitted to a complete conventional echocardiographic study. After that, the images were captured for global longitudinal strain (GLS). A blood sample was collected for brain natriuretic peptide (BNP) level. Ejection fraction obtained by Simpson's method was significantly higher in the hepatic pre-transplantation group (p < 0.001), as well as left atrial size (p < 0.001) and left ventricle size (p = 0.039). The left ventricular mass index was significantly higher in pre-transplantation group (p < 0.001). The left atrium volume (p = 0.008) and the left ventricular mass index (p t = 0.035) were higher in the post-transplant group. It was observed that the lower the BNP, the lower/more negative the GLS in the post-transplant group (p = 0.038 and r = 0.427). Significant reduction in the overall longitudinal strain of the left ventricle was detected before (p = 0.01) and after liver transplantation (p = 0.019). A subclinical left ventricular systolic dysfunction was evidenced by two-dimensional speckle tracking technique before and after liver transplantation, even when compared to normal values of the last pediatric meta-analysis.

Outcomes of liver transplantation in pediatric recipients with cardiovascular disease

LT exerts considerable stress on the heart perioperatively. Limited data exist on impact of cardiovascular diseases on LT children. This study evaluated the outcomes of children with CVD who underwent LT and compared with pretransplant findings. From 518 LT recipients, 82 (15.8%) had CVD. Sixty patients were classified as low-risk adjustment for congenital heart surgery 1 (RACHS 1 and 2). Five patients were classified as RACHS ≥3. The most common echocardiographic finding in the CVD patients (25/82) was ASD. CVD patients had more abnormal EKG (32.4% vs 14.5%, P < .001), abnormal chest X-ray (11.8% vs 1.4%, P < .001), and altered echocardiography (89.7% vs 15.4%, P < .001) findings compared with the No-CVD group pretransplant. Post-transplant, significant differences between groups were observed related to abnormal EKG (14.7% vs 7.0%, P = .03) and echocardiography (48.5% vs 3.2%, P < .01) findings. Pretransplant ASD spontaneously closed in 22 patients. At 1 and 5 years post-transplant, there was no difference in the survival rate between groups (P = .96). The prevalence of CVD in recipients of LT was high, and its presence was associated with significantly higher cardiac decompensation before and after LT. Minor and moderate cardiovascular disease did not impact the long-term survival.

Liver and systemic hemodynamics in children with cirrhosis: Impact on the surgical management in pediatric living donor liver transplantation

Cirrhosis in adults is associated with modifications of systemic and liver hemodynamics, whereas little is known about the pediatric population. The aim of this work was to investigate whether alterations of hepatic and systemic hemodynamics were correlated with cirrhosis severity in children. The impact of hemodynamic findings on surgical management in pediatric living donor liver transplantation (LT) was evaluated. Liver and systemic hemodynamics were studied prospectively in 52 children (median age, 1 year; 33 with biliary atresia [BA]). The hemodynamics of native liver were studied preoperatively by Doppler ultrasound and intraoperatively using invasive flowmetry. Portosystemic gradient was invasively measured. Systemic hemodynamics were studied preoperatively by Doppler transthoracic echocardiography and intraoperatively by using transpulmonary thermodilution. Hemodynamic parameters were correlated with Pediatric End-Stage Liver Disease (PELD) score and the histological degree of fibrosis (collagen proportionate area [CPA]). Cirrhosis was associated with a 60% reduction of pretransplant total liver flow (n = 46; median, 36 mL/minute/100 g of liver) compared with noncirrhotic livers (n = 6; median, 86 mL/minute/100 g; P = 0.002). Total blood flow into the native liver was negatively correlated with PELD (P < 0.001) and liver CPA (P = 0.005). Median portosystemic gradient was 14.5 mm Hg in children with cirrhosis and positively correlated with PELD (P < 0.001). Portal vein (PV) hypoplasia was observed mainly in children with BA (P = 0.02). Systemic hemodynamics were not altered in our children with cirrhosis. Twenty-one children met the intraoperative criteria for PV reconstruction using a portoplasty technique during the LT procedure and had a smaller PV diameter at pretransplant Doppler ultrasound (median = 3.4 mm; P < 0.001). Cirrhosis in children appears also as a hemodynamic disease of the liver, correlated with cirrhosis severity. Surgical technique for PV reconstruction during LT was adapted accordingly. Liver Transplantation 23 1440-1450 2017 AASLD.

Hepatopulmonary syndrome: the anaesthetic considerations

Hepatopulmonary syndrome (HPS) is a pulmonary complication observed in patients with chronic liver disease and/or portal hypertension, attributable to an intrapulmonary vascular dilatation that induces severe hypoxaemia. Considering the favourable long-term survival of HPS patients as well as the reversal of the syndrome with a functional liver graft, HPS is now an indication for orthotopic liver transplantation (OLT). Consequently, blood gas analysis and imaging techniques should be performed when cirrhotic patients present with shortness of breath as well as when OLT candidates are placed on the transplant waiting list. If the arterial partial pressure of oxygen (PaO2) is more than 10.7 kPa when breathing room air, HPS can be excluded and no other investigation is needed. When the PaO2 when breathing room air is 10.7 kPa or less, contrast-enhanced echocardiography should be performed to exclude pulmonary vascular dilatation. Lung function tests may also help detect additional pulmonary diseases that can contribute to impaired oxygenation. When contrast-enhanced echocardiography is negative, HPS is excluded and no follow-up is needed. When contrast-enhanced echocardiography is positive and PaO2 less than 8 kPa, patients should obtain a severity score that provides them with a reasonable probability of being transplanted within 3 months. In mild-to-moderate HPS (PaO2 8 to 10.6 kPa), periodic follow-up is recommended every 3 months to detect any further deterioration in PaO2. Although no intraoperative deaths have been directly attributed to HPS, oxygenation may worsen immediately following OLT due to volume overload and postoperative infections. Mechanical ventilation is often prolonged with an extended stay in the ICU. A high postoperative mortality (mostly within 6 months) is observed in this group of patients in comparison to non-HPS patients. However, the recovery of an adequate PaO2 within 12 months after OLT explains the similar outcome of HPS and non-HPS patients following OLT over a longer time period.