In-hospital Morbidity and Mortality Following Modified Blalock-Taussig-Thomas Shunts

Impact of Vascular Geometry on Thrombosis in Pediatric Patients With Modified Blalock-Taussig-Thomas Shunt: A Pilot Study

BACKGROUND

Thrombosis in modified Blalock-Taussig-Thomas shunts (mBTTS) poses a life-threatening risk for infants with shunt-dependent congenital heart disease. Although hemodynamics influence thrombosis, the specific geometric contributors remain unclear. This study aimed to identify key variables to inform future hemodynamic analysis, hypothesizing that brachiocephalic, subclavian artery, mBTTS, and/or pulmonary artery (PA) geometry play a critical role in clot formation.

METHODS AND RESULTS

We retrospectively analyzed 11 infants with hypoplastic left heart syndrome who underwent mBTTS placement. Using computed tomography and magnetic resonance imaging, we generated 3-dimensional models of the shunt and surrounding vasculature. Geometric variables related to shunt positioning and vascular insertion were measured and compared between patients with (n=5) and without (n=6) thrombotic occlusions. Significant differences in vascular geometry were observed between occluded and nonoccluded shunts. Occluded shunts had longer PA lengths (12.4 mm versus 8.4 mm, P=0.0130), increased variance in PA radius (0.03 versus 0.008, P=0.0216), greater PA tortuosity (1.03 versus 1.01, P=0.0043), and increased variance in torsion across the brachiocephalic and subclavian arteries (3200 mm-1 versus 17 500 mm-1, P=0.0390). These findings support our hypothesis that the vascular geometry surrounding the mBTTS plays a critical factor in clot formation. Additional variations in PA, brachiocephalic and subclavian artery geometry approached significance.

CONCLUSIONS

Significant geometric differences in the PA, brachiocephalic, and subclavian arteries were associated with mBTTS thrombosis, supporting the hypothesis that vascular geometry plays a critical role in clot formation. These findings provide a foundation for future hemodynamic analyses and may inform surgical planning to reduce thrombosis risk in patients with mBTTSs.

Outcomes and Risk Factors for Morbidity and Mortality of Systemic-to-Pulmonary Shunts in a Tertiary Hospital in Thailand

OBJECTIVES

A systemic-to-pulmonary shunt is the palliation of choice for many children with cyanotic congenital heart disease. However, significant morbidity and mortality related to these procedures and the postoperative course still exists. We aim to report our outcomes of systemic-to-pulmonary shunts as well as to define certain risk factors for adverse events.

MATERIALS AND METHODS

We retrospectively collected data from the electronic medical records of Ramathibodi hospital from January 01, 2013, to April 30, 2024. Demographic data, operative, and postoperative details were collected and reviewed. Inclusion criteria included patients whose primary operation was a systemic-to-pulmonary shunt. Exclusion criteria were patients diagnosed with hypoplastic left heart syndrome and whose medical record data were missing significant information.

RESULTS

There were initially 56 patients eligible for our study. After exclusion, the total number of patients enrolled was 42. Overall the results were excellent, with only one operative mortality, no discharge mortality, and four reinterventions. Outcomes between different shunt types, shunt sizes, surgical approaches, and diagnoses were statistically similar.

CONCLUSIONS

We demonstrate that systemic-to-pulmonary shunts are a safe and reliable procedure based on our results at a tertiary hospital in Thailand. We emphasize meticulous surgical techniques as well as utilization of proper and reproducible postoperative care protocols to optimize patient outcomes.

Timing of Cardiac Surgical Interventions and Postoperative Mortality in Children With Severe Congenital Heart Defects Across Europe: Data From the EUROlinkCAT Study

BACKGROUND

The purpose of this study was to evaluate the timing of the first cardiac surgery, the number of cardiac surgeries performed, and 30-day postoperative mortality rate for children with severe congenital heart defects (sCHDs) in their first 5 years of life.

METHODS AND RESULTS

This was a population-based data linkage cohort study linking information from 9 European congenital anomaly registries to vital statistics and hospital databases. Data were extracted for 5693 children with sCHDs born from 1995 to 2004. Subgroup analyses were performed for specific types of sCHD. Children with sCHDs underwent their first surgical intervention at a median age of 3.6 (95% CI, 2.6-4.5) weeks. The timing of the first surgery for most subtypes of sCHD was consistent across Europe. In the first 5 years of life, children with hypoplastic left heart underwent the most cardiac surgeries, with a median of 4.4 (95% CI, 3.1-5.6). The 30-day postoperative mortality rate in children aged <1 year ranged from 1.1% (95% CI, 0.5%-2.1%) for tetralogy of Fallot to 23% (95% CI, 12%-37%) for Ebstein anomaly. The 30-day postoperative mortality rate was highest for children undergoing surgery in the first month of life. Overall 5-year survival for sCHD was <90% for all sCHDs, except transposition of the great arteries, tetralogy of Fallot, and coarctation of the aorta.

CONCLUSIONS

There were no major differences among the 9 regions in the timing, 30-day postoperative mortality rate, and number of operations performed for sCHD. Despite an overall good prognosis for most congenital heart defects, some lesions were still associated with substantial postoperative death.

Outcome after stage 1 palliation in non-hypoplastic left heart syndrome patients as a univentricular palliation

OBJECTIVES

Studies focused on infants with univentricular heart undergoing stage I palliation other than the Norwood procedure remain a topic of great interest. This study evaluated the outcome of infants who underwent systemic to pulmonary shunt (SPS) or pulmonary artery banding (PAB).

METHODS

Infants who underwent SPS or PAB as stage I palliation between 1994 and 2019 were included. Survival and late systemic ventricular function were evaluated.

RESULTS

Out of 242 patients, 188 underwent SPS (77.7%) and 54 PAB (22.3%). Main diagnosis included tricuspid atresia, unbalanced atrioventricular septal defects, double inlet left ventricles and single ventricles with other morphology. Thirty-eight patients died before stage II palliation (15.7%). Stage II palliation was performed in 182 patients (75.2%), and mortality between stages II and III was 11 (5.6%). Stage III palliation was performed in 160 (66.1%) patients. Survival at 1, 5 and 15 years after stage I procedure was 81.9, 77.1 and 76.2%, respectively, and similar between both procedures (P = 0.97). Premature birth [P = 0.03, hazard ratio (HR) = 2.1], heterotaxy (P = 0.006, HR = 2.4) and dominant right ventricle (P = 0.015, HR = 2.2) were factors associated to mortality. Unbalanced atrioventricular septal defect (P = 0.005, HR = 4.6) was a factor associated to systemic ventricular dysfunction.

CONCLUSIONS

In patients with univentricular heart who underwent SPS and PAB as stage I palliation, survival at 15 years was 76%, regardless of th chosen approach. Premature birth, heterotaxy and dominant right ventricle were associated to mortality.

Percutaneous stent implantation for occluded central shunts in adults: A case report and review of current evidence

BACKGROUND

Patients with cyanotic complex congenital heart defects (CHDs) commonly undergo palliation with interposition of systemic-to-pulmonary shunts (SPSs). These palliative shunts are rarely found in adults with CHDs and can be complicated with progressive obstruction or total occlusion during follow-up. The best treatment option for shunt re-permeabilization is challenging and case-oriented because most patients are high risk candidates for redo surgeries. We aimed to review the current evidence on percutaneous stent implantation to treat failed SPSs.

METHODS

We performed a comprehensive literature review on percutaneous stent implantation to treat failed and occluded SPSs. We also reported the case of a 33-year-old man with cyanotic CHD and a occluded central aorto-pulmonary shunt, who was successfully treated with percutaneous balloon dilatation and subsequently stent implantation at our institution.

RESULT

We identified and included 31 articles reporting on 150 patients and 165 stent implantations in failed SPSs. The age of patients at the time of stent implantation ranged from 6 days to 47 years. The time between the surgical shunt creation and transcatheter intervention ranged from 1 day to 17 years. Overall, 161/165 (97.5%) stent implantations were successful. The most common clinical presentation was cyanosis and decreased atrial oxygen saturations and the indication for stent implantation was shunt obstruction and stenosis.

CONCLUSION

This review highlights the benefits of endovascular stenting to permeabilize failed SPSs in children and adults with complex CHD who are classified as poor candidates for re-surgical repair.