Congenital heart defects and heterotaxy syndrome Heterotaxy Hope Organization Terence Prendiville, pediatric cardiology fellow, Boston Children’s Hospital June 20th-23rd 2013 No conflicts of interest to declare Talk outline: ▪ Overview: spectrum of congenital heart defects seen in patients with heterotaxy syndrome ▪ Outcome data after repair of congenital heart disease ▪ Highlighting some of the differences between patients with and without heterotaxy syndrome passing through a cardiac intensive care unit: (next slide) Specific issues relating to congenital heart disease in heterotaxy syndrome ▪ Single ventricle physiology in those with heterotaxy syndrome – what’s known ▪ Fontan V’s biventricular repair (decision-waying) ▪ Pregnancy considerations in patients with congenital heart disease (including single ventricle) ▪ Risk of liver cirrhosis in patients with Fontan repair (and whether Heterotaxy syndrome affects this) ▪ Malrotation of the GI tract Heterotaxy syndrome: definition ▪ Heterotaxy is defined as any arrangement of organs across the body’s left-right axis that differs from complete situs solitus and complete situs inversus. Martina Brueckner, MD Associate Professor of Pediatrics (Cardiology) and of Genetics; Yale University School of Medicine Editorial, Circulation 2012 Origin of the term ‘heterotaxy’ Heteros: ‘other’ Taxis: ‘order or arrangement’ Stella Van Praagh, MD; Nadas Pediatric Cardiology, 2nd edition Incidence: 1 in 7,000 live births (1.7% of congenital heart disease) Normal and mirror image anatomy / position of internal organs Images: Laboratory Heymut Omran, MD; University Children’s Hospital Muenster, Germany Organ malposition (and / or maldevelopment) in heterotaxy syndrome Asplenia or polysplenia in heterotaxy syndrome ▪ Spleen frequently affected in heterotaxy syndrome: ABSENT (asplenia) MULTIPLE, small ‘splenules’ (polysplenia) Theory for link with heart disease in heterotaxy syndrome: Splenic development occurs at approximately the same time as the outflow tracts of the heart and the valves inside the heart (atrioventricular canal) Heart defects in patients with heterotaxy syndrome 1. Considerable variability 2. Definite clustering of cardiac malformations corresponding to either asplenia or polysplenia 3. Recent data that genes implicated in heterotaxy syndrome may be involved in congenital heart defects in patients without a formal diagnosis of heterotaxy syndrome Reference for heart disease in Heterotaxy syndrome: Nadas’ Pediatric Cardiology 2nd edition (2006) Ch.39: Cardiac Malpositions and the Heterotaxy Syndromes Stella Van Praagh Normally connected inferior vena cava Interrupted inferior vena cava Abnormal hepatic vein connections Absence of coronary sinus Bilateral superior vena cavae All pulmonary venous drainage to systemic vein All pulmonary venous drainage to RA or ipsilateral atria Atrial situs inversus Complete atrioventricular canal (common AVV) Intact atrioventricular canal septum L-looped ventricles Dextrocardia Normal biventricular size Left ventricular hypoplasia (or absence) Right ventricular hypoplasia (or absence) Sub-pulmonary stenosis Sub-aortic stenosis Double-outlet right ventricle Transposition of the Great Vessels Normally-related Great Vessels Asplenia (n=58) 100% 0% 28% 95% 71% 64% 2% 31% 69% 7% 38% 36% 45% 28% (14%) 10% (3%) 96% 2% 82% 9% 9% Adapted from Nadas Pediatric Cardiology, 2nd Ed 2007 Polysplenia (n=46) 20% 80% 80% 26% 50% 2% 37% 22% 33% 35% 30% 33% 63% 24% (0%) 11% (2%) 43% 22% 37% 2% 61% Heterotaxy syndrome: congenital heart disease associated with asplenia • Normally connected inferior vena cava • Pulmonary veins draining to other large vein (instead of to the left atrium) • Common (single) atrioventricular canal • Double-outlet right ventricle with pulmonary stenosis Heterotaxy syndrome: congenital heart disease associated with polysplenia • Interrupted inferior vena cava • Pulmonary veins draining to right atrium (instead of to the left atrium) • Common (single) atrioventricular canal • Normally-related great vessels exiting the heart Normally connected inferior vena cava Interrupted inferior vena cava Abnormal hepatic vein connections Absence of coronary sinus Bilateral superior vena cavae All pulmonary venous drainage to systemic vein All pulmonary venous drainage to RA or ipsilateral atria Atrial situs inversus Complete atrioventricular canal (common AVV) Intact atrioventricular canal septum L-looped ventricles Dextrocardia Normal biventricular size Left ventricular hypoplasia (or absence) Right ventricular hypoplasia (or absence) Sub-pulmonary stenosis Sub-aortic stenosis Double-outlet right ventricle Transposition of the Great Vessels Normally-related Great Vessels Asplenia (n=58) 100% 0% 28% 95% 71% 64% 2% 31% 69% 7% 38% 36% 45% 28% (14%) 10% (3%) 96% 2% 82% 9% 9% Adapted from Nadas Pediatric Cardiology, 2nd Ed 2007 Polysplenia (n=46) 20% 80% 80% 26% 50% 2% 37% 22% 33% 35% 30% 33% 63% 24% (0%) 11% (2%) 43% 22% 37% 2% 61% Single ventricle palliation in patients with heterotaxy syndrome Historic data on outcome after Fontan operation in patients with heterotaxy syndrome ▪ Pediatric Heart Network study: 546 survivors of the Fontan operation (aged 6-18 years old) ▪ 42 (8%) had heterotaxy syndrome ▪ Families and patients completed functional health status questionnaires ▪ Investigators performed echocardiography, EKG, exercise testing, cardiac MRI Functional state of patients with heterotaxy syndrome following the Fontan operation. Atz AM et al. Cardiol Young 2007 Results: ▪ Heterotaxy syndrome patients had different anatomical considerations (pulmonary veins, systemic ventricle and atrioventricular valves) ▪ No difference in: 1. Length of hospital stay 2. Number of post-operative complications 3. Exercise performance 4. Levels of BNP (marker of heart failure) 5. Health status questionnaire scores Pulmonary arteriovenous malformations… Blood that drains from the liver needs to pass through the lungs to prevent the growth of accessory vessels that drain blue blood back to the heart (bypassing the lungs) Heterotaxy syndrome patients can have an interrupted inferior vena cava (drains blood from liver to heart) Some heterotaxy syndrome pateints may require Fontan pathway modifications to re-direct liver blood flow through both lungs. Cavopulmonary pathway modification in patients with heterotaxy and newly diagnosed or persistent pulmonary arteriovenous malformations after a modified Fontan operation. McElhinney et al. J Thorac Cardiovasc Surg. 2011 Reporting the Boston Children’s Hospital experience on managing patients with borderline small left ventricles 34 patients with borderline left ventricle (2001-2010) • Careful selection of patients with borderline left ventricle (initial single ventricle palliation) LV end-diastolic volume z-score of -5 to -0.5 Failed any initial attempt at biventricular repair (balloon dil Ao V / coarct repair) or PGE1 dept. EXCLUDED: aortic atresia; mitral atresia; ventricular septal defect; l-transposed ventricles; transposed great vessels; heterotaxy syndrome (for purposes of analysis) Staged left ventricular recruitment after single-ventricle palliation in patients with borderline left heart hypoplasia. Emani et al. JACC. 2012 Reporting the Boston Children’s Hospital experience on managing patients with borderline small left ventricles 34 patients with borderline left ventricle (2001-2010) • Careful selection of patients with borderline left ventricle (initial single ventricle palliation) • Staged left ventricular recruitment and left ventricular rehabilitation Relief of inflow and outflow tract obstruction Resection of endocardial fibroelastosis Promotion of flow through the left ventricle I. (4mm restrictive atrial septal defect with resultant >5mmHg gradient across defect) II. Providing additional source of pulmonary blood flow Staged left ventricular recruitment after single-ventricle palliation in patients with borderline left heart hypoplasia. Emani et al. JACC. 2012 Endocardial fibroelastosis Reporting the Boston Children’s Hospital experience on managing patients with borderline small left ventricles Conversion to biventricular repair: 12 (40%) patients Surgically restricted atrial septum: 19 patients Single ventricle repair: 15 patients with Fontan; 3 patients with BDG 31 survivors (88%) 34 patients with borderline left ventricle (1 transplanted) Did not restrict atrial septum: 11 patients (2001-2010) 3 deaths (9%) Staged left ventricular recruitment after single-ventricle palliation in patients with borderline left heart hypoplasia. Emani et al. JACC. 2012 Reporting the Boston Children’s Hospital experience on managing patients with borderline small left ventricles Conversion to biventricular repair: 12 (40%) patients (1 transplanted) *Median length of hospitalization: 94 days Left ventricle volumes prior to biventricular conversion: Echo: LV EDV z-score: 0.21 (mean) MRI: LV EDV: 67mls/m2 (average) Median follow-up 2.9 years: no mortality (one heart transplant) Staged left ventricular recruitment after single-ventricle palliation in patients with borderline left heart hypoplasia. Emani et al. JACC. 2012 “In these patients (heterotaxy syndrome) aggressive pursuit of biventricular circulation may provide the best chance of long term survival” Sitiram Emani, Pedro del Nido Strategies to maintain biventricular circulation in patients with high-risk anatomy. Semin Thorac Cardiovasc Surg Pediatr Card Surg Ann. 2013 Non-cardiac anomalies in heterotaxy syndrome: 160 autopsy cases Extracardiac anomalies in the heterotaxy syndromes with focus on anomalies of midline-associated structures. Ticho, Goldstein and Van Praagh. Am J Cardiol 2000 Non-cardiac anomalies in heterotaxy syndrome ▪ Abnormal lung morphology: 92% ▪ Central nervous system anomaly: 7% (brain and spinal cord) ▪ Genitourinary anomalies: 14% (kidneys) ▪ Craniofacial involvement: 9% (incl. cleft lip / palate) ▪ Musculoskeletal involvement: 13% (e.g. scoliosis of spine) Non-cardiac anomalies in heterotaxy syndrome ▪ Gastrointestinal involvement: ALL PATIENTS – Malrotation of intestines (33%) – Stomach positioned on the right of the body (~42%) – Biliary atresia – Tracheo-esophageal fistula – Anal stenosis Intestinal malrotation and prophylactic Ladd’s procedure malrotation ▪ Intestinal malrotation (abnormally narrow base attachment of small bowel) places the patient at risk of volvulus (twisted bowel that is at risk of necrosis) volvulus Intestinal malrotation in heterotaxy syndrome and Ladd’s procedure: controversy • Screen all patients with upper gastro-intestinal fluoroscopy • Upper gastro-intestinal fluoroscopy may be challenging to interpret correctly • Intervene with preventative surgical procedure (Ladd’s) with evidence of malrotation • Preventative surgery is not without its own risks (by recent report) for complications including re-operation Intestinal malrotation in heterotaxy syndrome and Ladd’s procedure: controversy • Volvulus (twisted bowel) is a surgical • Don’t screen patients for malrotation emergency and can be a life-threatening event • Educate families fully about early signs of SYMPTOMATIC malrotation • Waiting until a patient presents with volvulus can put their life at risk • Appropriately investigate those that have any gastro-intestinal symptoms • ? Difficult medico-legally to NOT intervene of concern once there is radiology report of (asymptomatic) malrotation Symptoms of symptomatic malrotation / volvulus ▪ Vomiting (especially green or bilious) – acute or chronic ▪ Abdominal pain, constipation or diarrhea, blood stools ▪ Lethargy or irritability, loss of appetite 60% present with symptoms in the first month of life, 20% in the remaining first year, 20% thereafter Diagnosis: Upper gastrointestinal fluoroscopy Note: x-rays of the abdomen, CT scans, ultrasound and barium enemas may NOT diagnose malrotation. Children’s Hospital Los Angeles experience: managing patients with heterotaxy and ‘malrotation’ report ▪ Data from 2003-2011: 224 patients identified with heterotaxy syndrome (ISNPCHD definition) ▪ 62 patients: upper GI fluoroscopy screening ▪ 30 screened patients had ‘malposition’ and underwent a prophylactic Ladd’s procedure – 11 complications (8 re-operations) ▪ Incidence of volvulus: 0.2% ▪ 138 patients (asymptomatic) had no investigations: remained asymptomatic after 4 years of follow-up. Congenital heart disease and heterotaxy: upper gastrointestinal fluoroscopy can be misleading and surgery in an Asymptomatic patient is not beneficial. Papillon et al. Journal of Pediatric Surgery. 2013 Liver disease in Fontan patients (with heterotaxy syndrome) ▪ Boston Children’s Hospital / Brigham Women’s Hospital (unpublished data): ▪ 68 liver biopsies in patients after Fontan repair (13 with heterotaxy syndrome) Heterotaxy syndrome was not a risk factor for liver cirrhosis Heterotaxy syndrome diagnosis was not a risk factor for death or transplantation in this cohort Liver disease in Fontan patients (with heterotaxy syndrome) Unclear what significance (if any) biopsy-only evidence of fibrosis has in a patient after Fontan palliation Usually liver function tests are NORMAL in asymptomatic (biopsyproven fibrosis) patients Clinically apparent liver cirrhosis does complicate subsequent patient outcome Practical advice: Hep A and B vaccination Airway complications in patients with heterotaxy syndrome ▪ ▪ Circulation. 2012 May 8;125(18):2232-42. doi: 10.1161/CIRCULATIONAHA.111.079780. Epub 2012 Apr 12. High prevalence of respiratory ciliary dysfunction in congenital heart disease patients with heterotaxy. Nakhleh et al. Circulation 2012. Airway complications in patients with heterotaxy syndrome ▪ 42% (18/43) of patients with heterotaxy syndrome and congenital heart disease had documented ciliary dyskinesia (CD) ▪ CD risk higher in those heterotaxy syndrome patients with abnormal position of other thoraco-abdominal organs (in addition to the heart disease) ▪ This likely accounts for (at least some) of the post-operative respiratory complications after cardiac surgery in patients with heterotaxy syndrome Fertility in patients with heterotaxy syndrome ▪ Anecdotal experience from my adult congenital heart disease colleagues at BCH: ▪ Our program – 2 women with heterotaxy syndrome (polysplenia) who successfully carried pregnancies I. Fontan repair: 1 pregnancy (no complications) II. Biventricular heart repair: 4 pregnancies (no complications)– one child with heterotaxy syndrome and heart disease, another child with heart disease alone (TGA). ▪ Any concerns for male fertility unknown In summary Heterotaxy syndrome research has made significant advances in the last several years Researchers are unravelling the specific reasons that patients with heterotaxy syndrome and congenital heart disease may have a more challenging post-operative course Newer surgical techniques (left ventricular recruitment) will continue to advance the outcomes for children with heterotaxy syndrome The genetic underpinnings of heterotaxy syndrome is being actively pursued and will further enlighten our understanding of this complex disease Acknowledgements Research support from: Heterotaxy Foundation Keegan’s Spirit Foundation (Bruce Southers) My contact details: terence.prendiville@cardio.chboston.org ‘Preservation’ of cardiac developmental pathways: robust tolerance to perturbation An example of the variation in heart disease associated with one (well-known) cardiac gene…