Andrew Bullock

Redefining Expectations of Long-Term Survival After the Fontan Procedure Twenty-Five Years of Follow-Up From the Entire Population of Australia and New Zealand

Background— The life expectancy of patients undergoing a Fontan procedure is unknown. Methods and Results— Follow-up of all 1006 survivors of the 1089 patients who underwent a Fontan procedure in Australia and New Zealand was obtained from a binational population-based registry including all pediatric and adult cardiac centers. There were 203 atriopulmonary connections (AP; 1975–1995), 271 lateral tunnels (1988–2006), and 532 extracardiac conduits (1997–2010). The proportion with hypoplastic left heart syndrome increased from 1/173 (1%) before 1990 to 80/500 (16%) after 2000. Survival at 10 years was 89% (84%–93%) for AP and 97% (95% confidence interval [CI], 94%–99%) for lateral tunnels and extracardiac conduits. The longest survival estimate was 76% (95% CI, 67%–82%) at 25 years for AP. AP independently predicted worse survival compared with extracardiac conduits (hazard ratio, 6.2; P<0.001; 95% CI, 2.4–16.0). Freedom from failure (death, transplantation, takedown, conversion to extracardiac conduits, New York Heart Association III/IV, or protein-losing enteropathy/plastic bronchitis) 20 years after Fontan was 70% (95% CI, 63%–76%). Hypoplastic left heart syndrome was the primary predictor of Fontan failure (hazard ratio, 3.8; P<0.001; 95% CI, 2.0–7.1). Ten-year freedom from failure was 79% (95% CI, 61%–89%) for hypoplastic left heart syndrome versus 92% (95% CI, 87%–95%) for other morphologies. Conclusions— The long-term survival of the Australia and New Zealand Fontan population is excellent. Patients with an AP Fontan experience survival of 76% at 25 years. Technical modifications have further improved survival. Patients with hypoplastic left heart syndrome are at higher risk of failure. Large, comprehensive registries such as this will further improve our understanding of late outcomes after the Fontan procedure.

The extracardiac conduit Fontan procedure in Australia and New Zealand: hypoplastic left heart syndrome predicts worse early and late outcomes

OBJECTIVES To identify factors associated with hospital and long-term outcomes in a binational cohort of extracardiac conduit (ECC) Fontan recipients. METHODS All patients who underwent an ECC Fontan procedure from 1997 to 2010 in Australia and New Zealand were identified, and perioperative, follow-up, echocardiographic and reintervention data collected. Risk factors for early and late mortality, failure and adverse outcomes were analysed. RESULTS A total of 570 patients were identified, and late follow-up was available in 529 patients. The mean follow-up was 6.7 years (standard deviation: 3.5) and completeness of the follow-up was 98%. There were seven hospital mortalities (1%) and 21 patients (4%) experienced early failure (death, Fontan takedown/revision or mechanical circulatory support). Prolonged length of stay occurred in 10% (57 patients), and prolonged effusions in 9% (51 patients). Overall survival at 14 years was 96% (95% confidence interval [CI]: 93-98%), and late survival for patients discharged with intact Fontan was 98% (95% CI: 94-99%). The rates of late failure (late death, transplantation, takedown, New York Heart Association class III/IV or protein-losing enteropathy) and adverse events (late failure, reoperation, percutaneous intervention, pacemaker, thromboembolic event or supraventricular tachycardia) per 100 patient-years were 0.8 and 3.8, and their 14-year freedoms were 83% (95% CI: 70-91%) and 53% (95% CI: 41-64%), respectively. After adjustment for confounders, hypoplastic left heart syndrome (HLHS) was strongly associated with prolonged effusions (OR: 2.9, 95% CI: 1.4-5.9), late failure (hazard ratio [HR]: 2.8, 95% CI: 1.1-7.5) and adverse events (HR: 3.6, 95% CI: 1.3-7.5). CONCLUSIONS The extracardiac Fontan procedure provides excellent survival into the second decade of life, but half of patients will suffer a late adverse event by 14 years. Patients with HLHS are at higher risk of late adverse events than other morphological groups, but their survival is still excellent.

The Australia and New Zealand Fontan Registry: description and initial results from the first population-based Fontan registry

The Fontan procedure is the final in a series of staged palliations for single‐ventricle congenital heart disease, which encompasses rare and heterogeneous cardiac lesions. It represents an unusual and novel physiological state characterised by absence of a subpulmonary ventricle.

Twenty-three years of single-stage end-to-side anastomosis repair of interrupted aortic arches

OBJECTIVE This study defined long-term results of a policy of single-stage repair of interrupted aortic arch with end-to-side anastomosis. METHODS Records of 112 consecutive patients undergoing interrupted aortic arch repair between 1985 and 2007 were reviewed. Single-stage repair was performed in 95 patients, with 90 having end-to-side repair. RESULTS There were 11 in-hospital deaths (10%). Twelve patients needed arch reintervention during the same hospital stay: 7 for residual arch obstruction and 5 for left main bronchus obstruction. Nine patients were unavailable for follow-up. After a mean of 10 +/- 7 years, 6 late deaths occurred, for 18-year survival of 92% (95% confidence interval [CI], 84%-97%). Patients with end-to-side anastomoses had better 18-year survival (97%, 95% CI, 87%-99%, vs 74%, 95% CI, 44%-89%, P < .01). After discharge, 19 patients underwent further aortic arch intervention. The only factors predictive of late arch reintervention were technique other than end-to-side (P < .001) and reoperation for left outflow tract obstruction. Freedom from arch reintervention after end-to-side repair was 78% at 18 years (95% CI, 59%-89%). Another 16 patients had significant residual obstruction. The 18-year freedom from hypertension was 88% (95% CI, 72%-95%). CONCLUSIONS Single-stage repair with end-to-side anastomosis seems the best approach for most neonates with interrupted aortic arch, because it provides relief of the arch obstruction with low early mortality. After 2 decades of experience with this approach, incidence of late hypertension seems minimal. The need for further arch reintervention warrants close follow-up of these patients.

The Fontan epidemic: Population projections from the Australia and New Zealand Fontan Registry

BACKGROUND The number and age demographic of the future Fontan population is unknown. METHODS Population projections were calculated probabilistically using microsimulation. Mortality hazard rates for each Fontan recipient were calculated from survivorship of 1353 Fontan recipients in the Australia and New Zealand Fontan Registry, based on Fontan type, age at Fontan, gender and morphology. Projected rates of new Fontan procedures were generated from historical rates of Fontan procedures per population births. RESULTS At the end of 2014, the living Fontan population of Australia and New Zealand was 1265 people from an Australian and New Zealand regional population of 28 million (4.5 per 100,000 population). Of those, 165 (13%) received an atrio-pulmonary (AP) procedure, 262 (21%) a lateral tunnel (LT) procedure and 838 (66%) an extra-cardiac conduit (ECC) procedure. This population is expected to grow to 1917 (95% CI: 1846: 1986) by 2025 (5.8 per 100,000 population), with 149 (8%) AP procedures, 254 (13%) LT procedures, and 1514 (79%) ECC procedures. By 2045, the living Fontan population is expected to reach 2986 (95% CI: 2877: 3085; 7.2 per 100,000 population). The average age of the Fontan population is expected to increase from 18years in 2014 to 23years (95% CI: 22-23) by 2025, and 31years (95% CI: 30-31) by 2045. CONCLUSION The Australian and New Zealand population of patients alive after a Fontan procedure will double over the next 20years increasing the demand for heart-failure services and cardiac transplantation. Greater consideration for the needs of this mostly adult Fontan population will be necessary.

Ten-year outcomes of Fontan conversion in Australia and New Zealand demonstrate the superiority of a strategy of early conversion

OBJECTIVE To investigate the benefits of a strategy of early Fontan conversion. METHODS Using the Australia and New Zealand Fontan Registry, retrospective analysis of their long-term follow-up data was performed. RESULTS Between 1990 and 2014, a total of 39 patients underwent surgical conversion in 6 centres at a median age of 23.8 years (IQR: 19.3-28.2), 18.7 ± 5.0 years post-Fontan. One centre tended to perform conversion earlier: interval since first documented arrhythmia 2.9 ± 4.0 vs 4.0 ± 4.2 years, average NYHA Class 2 ± 0.4 vs 3 ± 0.9 (P = 0.008), mean number of preop anti-arrhythmics 1 ± 0.4 vs 2 ± 0.6 (P = 0.05). Two patients underwent conversion to an extracardiac conduit only, while 36 had concomitant right atrial cryoablation, of which 16 also had pacemaker implantation. Nine patients suffered major cardiac-related complications (7 low output syndrome, 3 ECMO, 3 acute renal failure, one stroke) (2/17 from the early conversion centre and 7/22 of the others; P = 0.14). Four patients died in hospital (10.3%) and 4 late after a median of 0.9 years [95% confidence interval (CI): 0.5-1] after conversion. An additional 2 patients needed transplantation at 1 and 8.8 years after conversion, respectively. The 10-year freedom from heart transplantation was 86% (95% CI: 51-97%). Outcomes from the centre with an early conversion strategy were significantly better: 8-year freedom from death or heart transplantation was 86% (95% CI: 53-96) vs 51% (95% CI: 22-74; log-rank P = 0.007). Eight additional patients required pacemaker implantation and 5 had arrhythmia recurrence. CONCLUSIONS Fontan conversion is associated with lasting survival outcomes up to 10 years after conversion. A strategy of surgical conversion at earlier stage of failure may be associated with better survival free from transplantation.

Long-term outcomes of patients with absent pulmonary valve syndrome: 38 years of experience.

BACKGROUND Absent pulmonary valve syndrome is associated with aneurysmal dilatation of the pulmonary arteries and compression of the tracheobronchial tree and may lead to significant respiratory compromise. We describe the outcomes of surgical correction of absent pulmonary valve syndrome and risk factors for mortality and reoperation. METHODS A review of 52 patients with absent pulmonary valve syndrome who underwent surgical correction between 1975 and 2013 was conducted. The median age and weight at repair were 9 months (range, 4 days to 24.2 years) and 6.9 kg (range, 1.8 to 56 kg). Preoperative intubation was required in 15 patients (29%), and 21 patients (40%) underwent urgent repair. The pulmonary valve was replaced with a valved conduit in 16 patients (31%) or monocusp valve in 16 patients (31%). Valveless repair was performed in 20 patients (38%). Pulmonary artery reduction was performed in 39 patients (75%), and 2 patients (4%) underwent a Lecompte maneuver. RESULTS The median follow-up time was 13 years (range, 1 month to 35 years). Early mortality was 18.8% (3 of 16) during 1975 through 1989, 19% (4 of 21) during 1990 through 2000, and 0% (0 of 15) during 2001 through 2013. Late mortality was 6.7% (3 of 45). Overall survival at 5, 10, and 20 years was 81.4%±5.6%. On multivariate analysis, preoperative ventilation (p=0.009) was the only risk factor for overall mortality. Freedom from late reoperation at 5, 10, and 20 years was 79.7%±6.9%, 69.4%±8.2%, and 52.1%±9.8%, respectively. No difference in reoperation rates was found between valved conduit, monocusp, or valveless techniques. Risk factors for late reoperation on multivariate analysis were prematurity (p=0.001) and neonatal primary repair (p=0.007). Longer postoperative ventilation periods were predicted by preoperative ventilation (p<0.001) and surgery during infancy (p=0.01). CONCLUSIONS Long-term survival for absent pulmonary valve syndrome has improved during the last decade. Preoperative ventilation predicted longer postoperative ventilation and mortality.

Fontan completion rate and outcomes after bidirectional cavo-pulmonary shunt.

OBJECTIVE To determine outcomes of patients undergoing a bidirectional cavo-pulmonary shunt (BCPS) in the Fontan era. METHODS From 1990 to 2000, 212 patients underwent a BCPS in a single institution at a mean age of 2.6+/-5 years. RESULTS Hospital mortality was 6% (13 patients). Five patients were lost to follow-up (3%). After a mean of 9+/-4 years, 15 patients had not yet been referred for Fontan surgery and their status was deemed satisfactory (11 1(1/2) ventricle repair, three BCPS and one patient converted to a bi-ventricular repair). Out of the remaining 179 patients who could potentially have reached a Fontan status, 141 had undergone the procedure and seven were awaiting Fontan completion. The expected completion rate of Fontan surgery after BCPS was 83% (148/179). Thirteen patients died and heart transplantation was necessitated in nine patients. Nine were deemed unsuitable for Fontan surgery for cardiac (seven), respiratory (one) or neurologic (one) reasons. After BCPS, the only predictors of late failure (death, heart transplantation or NYHA class III-IV) were not reaching Fontan status and the presence of bilateral superior vena cava (SVC). Ten-year survival was 99% (95% confidence interval (CI): 95-99%) for Fontan patients and 67% (95%CI: 50-80%) for those left with a BCPS. CONCLUSION In the present era, staging with BCPS represents a selection process in the Fontan pathway. Almost a fifth of the patients will not reach Fontan status. Outstanding results after Fontan surgery may hide a high attrition rate between BCPS and Fontan.

Repair of partial atrioventricular septal defect: a 37-year experience

OBJECTIVES Partial atrioventricular septal defect (pAVSD) is routinely repaired with a low mortality. However, limited data are available on the long-term follow-up of these patients. The current study was designed to determine long-term survival and morbidity of a large cohort of patients operated on at a single institution. METHODS From 1975 to 2012, 249 consecutive patients underwent pAVSD repair at the Royal Childrens Hospital. The follow-up data were obtained from hospital records, correspondence with cardiologists and primary care physicians, patient surveys and the state death registry. RESULTS The early mortality rate was 1.2% (3/249), while the long-term survival rate was 96% (95% CI: 93-98%) at 10 years and 94% (95% CI: 89-97%) at 30 years. Freedom from reoperation was 84% at 10 years and 75% at 30 years. The most common reoperations were left atrioventricular valve surgery (30/249, 12.1%), resection of left ventricular outflow tract obstruction (12/249, 4.8%) and closure of residual atrial septal defects (5/249, 2.0%). Implantation of a permanent pacemaker was required in 3.2% (8/249) of patients. Despite a substantial reoperation rate, only 43% of patients older than 18 years of age were seen by a cardiologist within the most recent 2 years of the study period, compared with 80% of those younger than 18 years (P < 0.001). CONCLUSIONS Repair of pAVSD is performed with a low mortality and excellent long-term survival. However, a substantial reoperation rate warrants close follow-up into adulthood.

Use of ACE inhibitors in Fontan: Rational or irrational?

BACKGROUND Despite a lack of evidence supporting the use of angiotensin-converting enzyme (ACE) inhibitors in patients with a Fontan circulation, their use is frequent. We decided to identify the rationale for ACE inhibitor therapy in patients within the Australia and New Zealand Fontan Registry. METHODS All patients in the Registry taking an ACE inhibitor at last follow up were identified, and a review of medical records was undertaken to determine the rationale for treatment initiation and reasons for treatment continuation or dose increase. RESULTS In 2015, 36% of the surviving patients in the Registry (462/1268) were taking an ACE inhibitor. Indications for initiation of therapy were ventricular systolic or diastolic dysfunction (29%), atrioventricular valve regurgitation (19%), preservation of normal ventricular function (7%), prolonged effusions at Fontan (6%), hypertension (6%), other (6%) and unknown (2%). No indication was stated in the remaining patients (25%). Those with hypoplastic left heart syndrome were more likely to be on an ACE inhibitor than those with an alternative primary morphology (70% vs 32%; p<0.001). Only 36% of the patients treated with an ACE inhibitor at last follow up (166/462) had an indication that would generally justify treatment in a two-ventricle circulation. CONCLUSION It is likely that the use of ACE inhibitors in patients with a Fontan circulation is excessive within our region. The coordination of prospective, multicentre studies and initiatives such as the Australia and New Zealand Fontan Registry will facilitate further investigations to guide treatment decisions in the growing Fontan population.