Tetralogy of Fallot Repair in Developing Countries: International Quality Improvement Collaborative

Early surgical outcome for Tetralogy Of Fallot In An African Setting; A Tanzanian experience using retrospective analysis of hospital data

BACKGROUND

Tetralogy of Fallot (TOF) is typically treated in infancy but often done late in many resource-limited countries, jeopardizing surgical outcomes. This study examined the early results of children undergoing primary complete TOF repair at the Jakaya Kikwete Cardiac Institute (JKCI) in Tanzania, an emerging cardiac center in Eastern Africa.

METHODS

A retrospective cohort study of children ≤ 18 years undergoing primary TOF complete repair between 2019 and 2021 was conducted. Patients with complex TOF and those with obvious genetic syndrome were excluded. Data on socio-demography, pre-and postoperative cardiac complications, Intensive Care Unit (ICU) and hospital stay, and in-hospital and 30-day mortality were analyzed. Logistic regressions were employed to find the factors for mortality, ICU, and hospital stays.

RESULTS

The I02 children underwent primary TOF complete repair were majority male (65.7%; n = 67), with a median age of 3.0 years (IQR: 2-6), ranging from 3 months to 17 years.Only 20 patients (19.6%) were below one year of age. Almost all (90%; n = 92) were underweight, with a mean BMI of 14.6 + 3.1 kg/m2 Haematocrits were high, with a median of 48.7 (IQR: 37.4-59.0). The median oxygen saturation was 81% (IQR:72-93). Over a third of patients (38.2%; n = 39) needed Trans annular patch (TAP) during surgery. The median ICU stay was 72 h (IQR:48-120), with ICU duration exceeding three days for most patients. The median hospital stay was 8.5 days (IQR:7-11), with 70 patients (68.2%)experiencing an extended hospital stay of > 7 days. Bacterial sepsis was more common than surgical site infection (5.6%; n = 6 vs. 0.9%;n = 1). No patient needed re-operation for the period of follow up. The in-hospital mortality rate was 5.9%, with no deaths occurring in children less than one year of age nor after discharge during the 30-day follow-up period. No statistically significant differences were observed in outcomes in relation to age, sex, levels of hematocrit and saturations, presence of medical illnesses, and placement of TAP.

CONCLUSION

TOF repairs in this African setting at a national cardiac referral hospital face challenges associated with patients' older age and compromised nutritional status during the surgery. Perioperative mortality rates and morbidity for patients operated at an older age remain elevated. It's important to address these issues to improve outcomes in these settings.

Effectiveness of pulmonary valve-sparing strategy for transatrial-transpulmonary repair of tetralogy of Fallot: a single institution experience

OBJECTIVE

We report the midterm results of our strategy utilizing transatrial-transpulmonary repair for tetralogy of Fallot at a single institution in a low-middle income country.

METHODS

Medical records were retrospectively reviewed for 532 consecutive patients who underwent definitive repair of tetralogy of Fallot at our institution from 2010 to 2020.

RESULTS

The median age and weight of patients in the study patients were 11.6 months (interquartile range, 8.6-17.2 months) and 7.5 kg (interquartile range, 6.8-8.8 kg). The pulmonary valve annulus was preserved (no transannular patch) in 398 patients (75%) and a mini-transannular patch was utilized for 134 patients (25%). The overall survival was 98% at 1 year, and 97% at 10-years follow-up, respectively. Longer postoperative ventilation time was the only risk factor correlated to early death (p = 0.004; Odds Risk, 1.04; 95% confidence intervals, 1.01-1.07). Fourteen patients required pulmonary valve replacement (2.6%, 14/532), four required surgical resection to relieve right ventricular outflow tract obstruction (0.8%, 4/532), and freedom from reoperation of the right ventricular outflow tract was 87% at 10 years. The only risk factor for right ventricular outflow tract reoperation was a postoperative systolic pressure gradient through the right ventricular outflow tract of greater than 50 mmHg (p < 0.001; HR, 47; 95% confidence intervals, 9.1-244). In total, 94.6% (471/489) of the patients were asymptomatic at the latest follow-up without significant arrhythmia.

CONCLUSION

At our institution in an low-middle income country, the transatrial-transpulmonary repair for tetralogy of Fallot has excellent midterm results with few reoperations required. Close long-term follow-up is essential for patients who undergo repair with a mini-transannular patch and may eventually require pulmonary valve replacement.

Tetralogy of Fallot in Low- and Middle-Income Countries

Low- and middle-incomes countries (LMICs) have limited resources for the diagnosis and treatment of congenital heart diseases such as tetralogy of Fallot. This is in part due to lack of infrastructures, financial means, and expertise. As a result, patients undergo surgery much later than in high-income countries. This delay in treatment results in right ventricular dysfunction, cardiac arrhythmias, and poor psychomotor development-complications that are all related to chronic hypoxia. There are limited data and a few small studies of patients treated for tetralogy of Fallot in LMICs, and, therefore, the aim of this review is to analyse and summarize the surgical outcomes of this LMIC population.

Primary or Delayed Repair for Complete Atrioventricular Septal Defect, Tetralogy of Fallot, and Ventricular Septal Defect: Relationship to Country Economic Status

OBJECTIVE

Primary repair in the first six months of life is routine for tetralogy of Fallot, complete atrioventricular septal defect, and ventricular septal defect in high-income countries. The objective of this analysis was to understand the utilization and outcomes of palliative and reparative procedures in high versus middle-income countries.

METHODS

The World Database of Pediatric and Congenital Heart Surgery identified patients who underwent surgery for: tetralogy of Fallot, complete atrioventricular septal defect, and ventricular septal defect. Patients were categorized as undergoing primary repair, repair after prior palliation, or palliation only. Country economic status was categorized as lower middle, upper middle, and high, defined by the World Bank. Multiple logistic regression models were utilized to identify independent predictors of hospital mortality.

RESULTS

Economic categories included high (n = 571, 5.3%), upper middle (n = 5,342, 50%), and lower middle (n = 4,793, 49.7%). The proportion of patients and median age with primary repair were: tetralogy of Fallot, 88.6%, 17.7 months; complete atrioventricular septal defect, 83.4%, 7.7 months; and ventricular septal defect, 97.1%, ten months. Age at repair was younger in high income countries (P < .0001). Overall mortality after repair was lowest in high income countries. Risk factors for hospital mortality included prematurity, genetic syndromes, and urgent or emergent operations (all P < .05).

CONCLUSIONS

Primary repair was selected in >90% of patients, but definitive repair was delayed in lower and upper middle income countries compared with high-income countries. Repair after prior palliation versus primary repair was not a risk factor for hospital mortality. Initial palliation continues to have a small but important role in the management of these three specific congenital heart defects.

Coronavirus disease 2019 convalescent children: outcomes after congenital heart surgery

BACKGROUND

Children with exposure to coronavirus disease 2019 in recent times (asymptomatic or symptomatic infection) approaching congenital heart surgery programme are in increasing numbers. Understanding outcomes of such children will help risk-stratify and guide optimisation prior to congenital heart surgery.

OBJECTIVE

The objective of the present study was to determine whether convalescent coronavirus disease 2019 children undergoing congenital heart surgery have any worse mortality or post-operative outcomes.

DESIGN

Consecutive children undergoing congenital heart surgery from Oct 2020 to May 2021 were enrolled after testing for reverse transcription-polymerase chain reaction or rapid antigen test and immunoglobulin G antibody prior to surgery. Convalescent coronavirus disease 2019 was defined in any asymptomatic patient positive for immunoglobulin G antibodies and negative for reverse transcription-polymerase chain reaction or rapid antigen test anytime 6 weeks prior to surgery. Control patients were negative for any of the three tests. Mortality and post-operative outcomes were compared among the groups.

RESULTS

One thousand one hundred and twenty-nine consecutive congenital heart surgeries were stratified as convalescence and control. Coronavirus disease 2019 Convalescent (n = 349) and coronavirus disease 2019 control (n = 780) groups were comparable for all demographic and clinical factors except younger and smaller kids in control. Convalescent children had no higher mortality, ventilation duration, ICU and hospital stay, no higher support with extracorporeal membrane oxygenation, high flow nasal cannula, no higher need for re-intubations, re-admissions, and no higher infections as central line-associated bloodstream infection, sternal site infection, and ventilator-associated pneumonia on comparison with coronavirus disease 2019 control children.

CONCLUSIONS

Convalescent coronavirus disease 2019 does not have any unfavourable outcomes as compared to coronavirus disease 2019 control children. Positive immunoglobulin G antibody screening prior to surgery is suggestive of convalescence and supports comparable outcomes on par with control peers.

Pulmonary valve replacement may not restore ventricular volume and functional status in patients with pulmonary regurgitation after late tetralogy of Fallot repair

OBJECTIVES

Clinically, tetralogy of Fallot (TOF) patients who underwent repair late (older than 2 years) appears to have worse outcomes after pulmonary valve replacement than patients who underwent repair early. We proceeded to review the clinical features of late-repaired TOF patients who required pulmonary valve replacement.

METHODS

Fifty patients who underwent pulmonary valve replacement after TOF repair over the age of 2 years from 2000 to 2018 were retrospectively reviewed. Pre- and postoperative cardiac magnetic resonance imaging, cardiopulmonary exercise tests, and cardiac catheterization were analysed.

RESULTS

The median age of patients at the time of TOF repair and pulmonary valve replacement was 3.6 and 23.4 years, respectively. The median interval from TOF repair to pulmonary valve replacement was 20.5 years. Cardiac magnetic resonance imaging and cardiopulmonary exercise tests were performed at a median of 5.9 and 3.7 years after pulmonary valve replacement, respectively. Cardiac magnetic resonance revealed that there were significant changes in the indexed values of the right ventricle end-diastolic volume (164.7-106.9 ml/m2, P < 0.001), end-systolic volume (101.4-64.9 ml/m2, P < 0.001), stroke volume (66.8-48.0 ml/m2, P = 0.007) and cardiac output (5.1-3.6 l/m2, P = 0.040). Twenty-eight percentage of patients achieved normalization of the right ventricular volume after pulmonary valve replacement. In the exercise test, the maximum rate of oxygen consumption (72.5-69.5%) and oxygen pulse (95.0-83.0%) changed without statistical significance.

CONCLUSIONS

Although pulmonary valve replacement after late TOF correction improves right ventricular volume status, only a minority of patients achieve normalization of right ventricular end systolic volume and a normal functional status.

Mortality Risk Factors in Tetralogy of Fallot Patients Undergoing Total Correction

A total correction is a preferred treatment for Tetralogy of Fallot patients in every part of the world. However, the mortality in developing countries was as high as 6.9% to 15.3%. This was a retrospective analytic study that analyzed pre and post-operative risk factors that affected mortality on TOF patients that were performed total correction in Indonesia. A total of 47 TOF patients that were performed total correction from January 2016 to September 2019 were enrolled in this study based on the inclusion criteria. Preoperative and post-operative data were obtained from medical records. In this research, the majority of mortality was found in male patients (39.3%), while the female’s rate was lower (36.8%). Overall mortality was 38.3% and one operative death was found. The average age of patients was 84.12 months (12-210 months), whereas the average height (85.56 ± 36.17cm vs. 112.93 ± 21.73) and weight (17.22kg vs. 28.21kg) were lower for mortality patients. Some significant preoperative variables were identified as mortality risk factors such as: age below 60 months (p=0.047), smaller weight and height (p=0.008; p=0.002), abnormal hematocrit (p=0.002), and oxygen saturation below 75% (p=0.018). Significant post-operative risk factors included: temperature above 38.5⁰C (p=0.000), and ventilator time of more than 48 hours (p=0.033). In conclusion, the mortality of TOF patients undergoing a total correction in developing countries was quite high. It was associated with some risk factors, such as younger age, lower weight and height, low oxygen saturation, post-operative fever, and prolonged ventilator time.

Prognostic Value of Preoperative Absolute Lymphocyte Count in Children With Tetralogy of Fallot

Background

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Absolute lymphocyte count (ALC) is a low‐cost and easy‐to‐obtain inflammatory indicator; however, its association with the prognosis of patients with TOF remains unknown. This study aimed to determine the prognostic value of preoperative ALC in children with TOF.

Methods and Results

This retrospective study included 707 patients aged <6 years who underwent corrective operations for TOF between January 2016 and December 2018 in Fuwai Hospital, China. The end points were mortality, extracorporeal membrane oxygenation placement, postoperative hospital stay >30 days, and severe postoperative complications; patients were grouped on the basis of prognosis: poor prognosis (n=76) and good prognosis (n=631). Univariable and multivariable logistic regression analyses were performed to identify the independent risk factors for poor prognosis, on which a risk scoring system was based. The receiver operating characteristic curve was used to assess model performance. Using another model without ALC, the effect of the addition of ALC was assessed. Results suggested that ALC was an independent factor with a cutoff point of 4.36×10⁹/L. The addition of ALC improved the area under the curve from 0.771 to 0.781 (P<0.001). To avoid reverse causality and further control for confounding factors, the patients were further divided on the basis of ALC level, and a propensity score matching was performed; 117 paired patients were identified for further analysis. Low ALC levels had an odds ratio of 3.500 (95% CI, 1.413–8.672).

Conclusions

Low preoperative ALC represents an independent predictor of poor prognosis in children with TOF.

Pulmonary Vein Stenosis: A Rare Disease with a Global Reach

Pulmonary vein stenosis (PVS) is a rare, but high mortality and resource intensive disease caused by mechanical obstruction or intraluminal myofibroproliferation, which can be post-surgical or idiopathic. There are increasing options for management including medications, cardiac catheterization procedures, and surgery. We queried the International Quality Improvement Collaborative for Congenital Heart Disease (IQIC) database for cases of PVS and described the cohort including additional congenital lesions and surgeries as well as infectious and mortality outcomes. IQIC is a quality improvement project in low-middle-income countries with the goal of reducing mortality after congenital heart surgery. Three cases were described in detail with relevant images. We identified 57 cases of PVS surgery, with similar mortality to higher income countries. PVS should be recognized as a global disease. More research and collaboration are needed to understand the disease, treatments, and outcomes, and to devise treatment approaches for low resource environments.

Predictors of a complicated course after surgical repair of tetralogy of Fallot

Background

In this study, we aimed to evaluate the patient and surgical factors affecting prolonged hospital stay and major adverse events after surgical repair of tetralogy of Fallot and to identify the predictors of a complicated course after surgical repair.

Methods

A total of 170 consecutive patients (96 males, 74 females; median age 12 months; range, 1 to 192 months) who underwent surgical repair of tetralogy of Fallot between January 2015 and April 2018 were retrospectively reviewed. A mechanical ventilation duration of >24 h, an intensive care unit stay of >3 days, and a hospital stay of >7 days were considered as prolonged. Unplanned reoperation, complete heart block requiring a permanent pacemaker implantation, renal failure, diaphragmatic paralysis, neurological deficit, sudden circulatory arrest, need for extracorporeal membrane oxygenation, and death were considered as major adverse events.

Results

The median time to hospital discharge was 8.0 (range, 5.0 to 40.0) days. Higher preoperative hematocrit levels prolonged the length of hospital stay (odds ratio: 1.12, 95% confidence interval 1.1-1.2, p<0.001). A total of 28 major adverse events were observed in 17 patients (10%). Lower pulmonary artery annulus Z-score (odds ratio: 0.5, 95% confidence interval 0.3-0.9, p=0.01) and residual ventricular septal defects (odds ratio: 54.6, 95% confidence interval 1.6-1,874.2, p=0.03) were found to increase mortality. Residual ventricular septal defect was also a risk factor for major adverse events (odds ratio: 12.4, 95% confidence interval 1.5-99.9, p=0.02).

Conclusion

Preoperative and operative factors such as high preoperative hematocrit, low preoperative oxygen saturation, low pulmonary annulus Z-score, Down syndrome, residual ventricular septal defects, and the use transannular patch were found to be associated with prolonged length of hospital stay, prolonged mechanical ventilation, prolonged intensive care unit stay, and increased development of major adverse events.

Congenital heart disease in low-and-middle-income countries: Focus on sub-Saharan Africa

The etiology of congenital heart disease (CHD) is multifactorial. The birth prevalence of CHD is shaped by a wide variety of maternal, fetal, and neonatal risk factors, along with the rates of prenatal diagnosis and terminations of pregnancy, all of which have geographic variability Epidemiology data availability from low-and-middle-income countries (LMIC) on CHD prevalence, morbidity, and mortality are far more limited than from high income countries. Data on specific genetic, environmental, and prenatal risk associated with CHD are almost nonexistent. In this article, we will focus on defining what data are available, genetic risk factors, birth and overall prevalence, morbidity, and the impact of limited access to interventions, both surgery and cardiac catheterizations. We will highlight CHD in sub-Saharan Africa to detail epidemiology studies in the poorest regions of the world. Existing literature as well as estimates from the Global Burden of Disease Study (http://ghdx.healthdata.org) form the basis for this review. The intersection of poverty, high fertility rates, and limited access to care results in a unique profile of CHD in LMIC. CHD is not a preventable disease (by most standards), so early detection and access are our key interventions to improve the dire outcomes for children in low-resources settings of the world.

Bidirectional Glenn for residual outflow obstruction in Tetralogy of Fallot

BACKGROUND

Residual right ventricular outflow obstruction during Tetralogy of Fallot repair necessitates peri-operative revision often requiring trans-annular patch with its negative sequels. Bidirectional Glenn shunt in this setting reduces trans-pulmonary gradient to avoid revision.

METHODS

Bidirectional Glenn shunt was added during Tetralogy repair in patients with significant residual obstruction. A total of 53 patients between January, 2011 and June, 2018 were included. Final follow-up was conducted in July, 2018.

RESULTS

Mean age at operation was 5.63±3.1 years. Right to left ventricular pressure ratio reduced significantly (0.91±0.09 versus 0.68±0.05; p&lt;0.001) after bidirectional Glenn, avoiding revision in all cases. Glenn pressures at ICU admission decreased significantly by the time of ICU discharge (16.7±3.02 versus 13.5±2.19; p&lt;0.001). Pleural drainage ≥ 7 days was seen in 14 (26.4%) patients. No side effects related to bidirectional Glenn-like facial swelling or veno-venous collaterals were noted. Mortality was 3.7%. Discharge echocardiography showed a mean trans-pulmonary gradient of 32.11±5.62 mmHg that decreased significantly to 25.64±5 (p&lt;0.001) at the time of follow-up. Pulmonary insufficiency was none to mild in 45 (88.2%) and moderate in 6 (11.8%). Mean follow-up was 36.12±25.15 months (range 0.5-90). There was no interim intervention or death. At follow-up, all the patients were in NYHA functional class 1 with no increase in severity of pulmonary insufficiency.

CONCLUSION

Supplementary bidirectional Glenn shunt significantly reduced residual right ventricular outflow obstruction during Tetralogy of Fallot repair avoiding revision with satisfactory early and mid-term results.