The Incidence and Factors Associated with the Recurrence of Supraventricular Tachycardia in Children: 15 Years Experience from Middle-Income Country.

Limited data are available concerning supraventricular tachycardia (SVT) recurrence. Hence, this study aimed to determine the incidence, outcome, and factors associated with SVT recurrence. This retrospective, observational, population-based study was conducted among children with SVT from 2006 to 2020. The primary outcome measure was SVT recurrence. Kaplan Meier analysis was used to estimate SVT-free at 1, 5, and 10 years after diagnosis. Cox regression analysis was used to identify independent factors associated with recurrence. There were 156 patients with SVT with a median age at diagnosis of 1.9 years (Interquartile range [IQR] 11 days to 8.7 years) and follow-up for a median of 3.5 years (IQR 1.7 to 6.1 years). 35 patients (22%) had recurrent SVT at a median age of 7.8 years (IQR 4.4 to 12 years). Infants with Wolff-Parkinson-White Syndrome (WPW) had the highest recurrence (11/16, 68%), with 33% SVT-free at 5 years follow-up. The lowest recurrence rate was observed in neonatal diagnosis (2/54, 3.7%) with 98% SVT-free at 5 years follow-up. The independent factors associated with the recurrence of SVT were the diagnosis of WPW with an adjusted hazard ratio (aHR) of 5.2 (95% CI 2.4-11.2), age of more than 1 year at diagnosis (aHR 3.7 95% CI 1.4-9.7), and combine with or need second-line therapy (aHR 4.0 95% CI 1.5-10.7). One in five children with SVT experienced a recurrence, which is more likely for those with WPW, multiple maintenance therapy, and older age at first presentation. Whereas neonates with non-WPW may benefit from shorter maintenance therapy.

Survival and factors associated with mortality among infants with anorectal malformation: a population-based study from a middle-income country.

Limited data on the survival of anorectal malformation (ARM) patients from lower- and middle-income countries is available. This retrospective population-based study from the State of Johor, Malaysia, determines the incidence, mortality rate, and survival of ARM patients and factors associated with mortality. Kaplan-Meier survival analysis was used to estimate the survival of ARM patients at 1, 5, and 10 years. In addition, multivariate Cox regression analysis was used to analyze mortality-related factors. There were 175 ARM patients among 803,850 live births, giving an overall ARM incidence of 2.2 (95% confidence interval [CI], 1.9 to 2.5) per 10,000 live births. The male-to-female ratio was 1.5:1. There were 122 (69%) non-isolated ARM, of which 41 were Trisomy-21 and 34 had VACTERL association. Seventy-three (42%) had congenital heart disease (CHD), with 38 severe and 35 non-severe CHD. Overall, 33 (19%) patients died, with a median age of death of 5.7 months (interquartile range (IQR) 25 days to 11.2 months). The overall estimated 1-, 5-, and 10-year survival rate for ARM patients was 82% (95% CI, 76-89%), 77% (95% CI, 70-84%), and 77% (95% CI, 70-84%), respectively. Univariate analysis shows that non-isolated ARM, VACTERL association, and severe CHD were associated with mortality. However, only severe CHD is the independent factor associated with mortality, with a hazard ratio of 4.0 (95% CI, 1.9-8.4).  Conclusion: CHD is common among ARM patients, and one in five ARM patients had a severe cardiac defect, significantly affecting their survival. What is Known: • VACTERL association and congenital heart disease are common in patient with anorectal malformation. • Low birth weight and prematurity are associated with a lower rate of survival. What is New: • Congenital heart disease is common in ARM patients in a middle-income country. • Severe congenital heart disease plays a significant role in the survival of patients with an anorectal malformation in lower- and middle-income countries.

Intravenous immunoglobulin-resistant Kawasaki disease: Risk factors in children in a middle-income country.

Background: Identifying risk factors in patients with intravenous immunoglobulin (IVIG) resistance Kawasaki disease (KD) is vital in managing and preventing coronary artery aneurysms (CAAs). We aimed to study the risk factors for IVIG resistance KD in Malaysian children. Methods: This retrospective observational study of children with KD was conducted at two tertiary hospitals in Malaysia from January 2014 to December 2019. Multivariable binary logistic regression was used to analyze the risk factors associated with IVIG resistance. Results: A total of 174 patients, 118 males (67.8%) with a median age of 1.4-year-old (interquartile range: 0.1-12.1-year-old), were analyzed. Early (<5 days) and late (>10 days) IVIG treatments were observed in 14 (8.1%) and 19 (11.0%), respectively. Thirty-two patients (18.4%) had IVIG resistance. The independent factors associated with IVIG resistance were high white cell count, hypoalbuminemia, and extremities changes with an odd ratio of 4.7, 3.0, and 4.0, respectively. In addition, CAA was significantly higher in IVIG resistance compared to IVIG responder patients (57.5% [19/33] vs. 23.4% [33/141], P < 0.001). The sensitivity was high in Harada (93.8%) but low in Kobayashi and Egami (46.9% and 34.4%, respectively). The specificity was high with Egami (79.6%) but low in Harada and Kobayashi (22.5% and 64.1%, respectively). Conclusion: Leukocytosis, hypoalbuminemia, and extremities changes were independent risk factors for IVIG resistance. The variation in sensitivity and specificity of the Japanese scoring makes it unsuitable for predicting IVIG resistance in Malaysian children.

Pediatric Rheumatic Heart Disease in a Middle-Income Country: A Population-Based Study.

INTRODUCTION: Rheumatic heart disease (RHD), a debilitating complication from rheumatic fever, remains a problem in low- and middle-income countries. This study describes the incidence, prevalence, modifiable risk factors for severe RHD and immediate outcome of pediatric RHD. METHODS: This population-based and observational cohort study reviewed pediatric RHD patients (0-18 years) from the Sabah Pediatric Rheumatic Heart Registry from 2015 till 2018. RESULTS: A total of 188 RHD were reviewed with 120 new cases. The incidence of RHD is 2.19 [95% confidence interval (CI): 1.83-2.61] per 100 000 population, with a rising trend over time. Meanwhile, the prevalence of RHD was 13.78 (95% CI: 11.92-15.86) per 100 000 pediatric population. The majority of patients were from indigenous groups (59.0%), male (56.4%) with a mean age of 14.3 (3.31) years. About 77.9% had the lowest household income, and a significant proportion lived in overcrowded conditions. At diagnosis, 59% were diagnosed with severe RHD. There is heightened risk but no statistical significance between modifiable factors (low weight and height percentile at diagnosis, lowest income group, renting a house, overcrowding and healthcare access of more than 5 km) with severe RHD. Severe RHD is significantly associated with risk for intervention (p = 0.016). Sixteen (13.8%) patients required surgical intervention. About 97.6% of patients were on intramuscular benzathine penicillin G with 84.5% compliance. CONCLUSION: The rising prevalence and incidence of pediatric RHD in Sabah, with the most being severe RHD at diagnosis, necessitates the development of an echocardiographic screening and a comprehensive national disease program.

Tilt-table Echocardiography Unmasks Early Diastolic Dysfunction in Patients With Hemoglobinopathies.

Individuals with hemoglobinopathy (sickle cell anemia and thalassemia major) are at risk for cardiac complications such as heart failure and cardiomyopathy. Diastolic dysfunction is known to precede systolic dysfunction in many cardiac diseases. This study sought to determine whether changes in left atrial (LA) function during manipulation of cardiac preload by tilt-table echocardiography can unmask subclinical diastolic dysfunction in pediatric patients with hemoglobinopathies. Eleven sickle cell anemia, 9 transfusion-dependent thalassemia major, and 10 control subjects underwent tilt-table echocardiogram in the supine (loading) and 30-degree upright (unloading) positions and cardiac magnetic resonance imaging (MRI). Echocardiography assessed LA and left ventricular (LV) strain, strain rate, mitral inflow, and annular velocities. MRI assessed LV function, myocardial T1 and T2* for iron deposition. Both thalassemia major and sickle cell anemia patients had normal LV function and no evidence of cardiac iron deposition on MRI T2* measurements. During cardiac loading, controls appropriately increased LA conduit (P=0.002) and reservoir strain (P=0.002), mitral e' velocity (P<0.0001) and medial e' velocity (P=0.002), while the hemoglobinopathy patients showed no change in these parameters. In pediatric sickle cell anemia and thalassemia, tilt-table echocardiography unmasked a failure to augment LA function in response to loading, suggesting altered myocardial relaxation is present, before evidence of iron overload or systolic dysfunction.

Ten-year trend in prevalence and outcome of Down syndrome with congenital heart disease in a middle-income country.

Limited data are available on the survival of patients with Down syndrome and congenital heart disease (CHD) from middle-income countries. This retrospective cohort study was performed to determine the trends in the prevalence and survival of such patients born from January 2006 to December 2015 in Malaysia. Among 754 patients with Down syndrome, 414 (55%) had CHD, and no significant trend was observed during the 10 years. Of these 414 patients, 30% had lesions that closed spontaneously, 35% underwent surgery/intervention, 9% died before surgery/intervention, and 10% were treated with comfort care. The overall mortality rate was 23%, the median age at death was 7.6 months, and no significant changes occurred over time. The early and late post-surgery/intervention mortality rates were 0.7% and 9.0%, respectively. Most deaths were of non-cardiac causes. The overall 1-, 5-, and 10-year survival rates were 85.5%, 74.6%, and 72.9%, respectively. Patients with severe lesions, persistent pulmonary hypertension of the newborn, atrioventricular septal defect, and pulmonary hypertension had low survival at 1 year of age.Conclusion: The prevalence of CHD in patients with Down syndrome is similar between Malaysia and high-income countries. The lower survival rate is attributed to limited expertise and resources which limit timely surgery. What is Known: • The survival of patients with Down syndrome with congenital heart disease (CHD) has improved in high-income countries. However, little is known about the survival of patients with Down syndrome with CHD from middle-income countries. • In the Caucasian population, atrioventricular septal defect is the most common type of CHD associated with Down syndrome. What is New: • In middle-income countries, the prevalence of CHD is the same as in high-income countries, but with a lower survival rate. • In the Asian population, ventricular septal defect is the most common type of CHD in patients with Down syndrome.

The birth prevalence, severity, and temporal trends of congenital heart disease in the middle-income country: A population-based study.

OBJECTIVES: There is limited data on congenital heart disease (CHD) from the lower- and middle-income country. We aim to study the epidemiology of CHD with the specific objective to estimate the birth prevalence, severity, and its trend over time. DESIGN: A population-based study with data retrieved from the Pediatric Cardiology Clinical Information System, a clinical registry of acquired and congenital heart disease for children. SETTING: State of Johor, Malaysia. PATIENTS: All children (0-12 years of age) born in the state of Johor between January 2006 and December 2015. INTERVENTION: None. OUTCOME MEASURE: The birth prevalence, severity, and temporal trend over time. RESULTS: There were 531,904 live births during the study period with 3557 new cases of CHD detected. Therefore, the birth prevalence of CHD was 6.7 per 1000 live births (LB) (95% confidence interval [CI]: 6.5-6.9). Of these, 38% were severe, 15% moderate, and 47% mild lesions. Hence, the birth prevalence of mild, moderate, and severe CHD was 3.2 (95% CI: 3.0-3.3), 0.9 (95% CI: 0.9- 1.1), and 2.6 (95% CI: 2.4-2.7) per 1000 LB, respectively. There was a significant increase in the birth prevalence of CHD, from 5.1/1000 LB in 2006 to 7.8/1000 LB in 2015 (P < .0001) due to increase in detection of both mild (1.9/1000 LB in 2006 to 3.9/1000 LB in 2015, P < .001) and severe CHD (1.8/1000 LB in 2005 to 2.9/1000 LB in 2015, P < .001). CONCLUSIONS: The birth prevalence of CHD was 6.7 per 1000 live births, and two in five were severe and significantly associated with syndrome and extracardiac defect. There was a significant increase in the detection of severe lesions in recent years leading to more burden to resources that are already limited in the middle-income country. Therefore, strategic and comprehensive pediatric and congenital heart surgery program is required.

Survival and Associated Risk Factors for Mortality Among Infants with Critical Congenital Heart Disease in a Developing Country.

Critical congenital heart disease (CCHD) is associated with significant morbidity and mortality. However, data on survival of CCHD and the risk factors associated with its mortality are limited. This study examined CCHD survival and the risk factors for CCHD mortality. Using a retrospective cohort study of infants born with CCHD from 2006 to 2015, survival over 10 years was estimated using Kaplan-Meier analysis, and the risk factors for mortality were analyzed using multivariate Cox proportional hazards regression. A total of 491 CCHD cases were included in the study, with an overall mortality rate of 34.8% (95% confidence interval [CI] 30.6-39.2). The intervention/surgical mortality rate was 9.8% ≤ 30 days and 11.5% > 30 days after surgery, and 17% died before surgery or intervention. The median age at death was 2.7 months [first quartile: 1 month, third quartile: 7.3 months]. The CCHD survival rate was 90.4% (95% CI 89-91.8%) at 1 month, 69.3% (95% CI 67.2-71.4%) at 1 year, 63.4% (95% CI 61.1-65.7%) at 5 years, and 61.4% (95% CI 58.9-63.9%) at 10 years. Weight of < 2 kg at diagnosis, associated syndromes, poor pre-operative condition, and non-duct-dependent CCHD were independent risk factors for poor survival, with hazard ratios of 2.61, 2.10, 2.22, and 1.70, respectively. CCHD is associated with a high mortality rate. Low weight, poor pre-operative condition, associated syndromes, and non-duct-dependent CCHD are significant risk factors affecting the survival of infants with CCHD.

Impaired Single Right Ventricular Function Compared to Single Left Ventricles during the Early Stages of Palliation: A Longitudinal Study.

BACKGROUND: Single right ventricles (SRV) are postulated to be disadvantaged compared with single left ventricles (SLV). We compared the evolution of SRV versus SLV function during infancy using conventional measures and speckle-tracking echocardiography (STE). We hypothesized that the SRV is mechanically disadvantaged during early infancy. METHODS: SRVs (n = 32) were compared with SLVs (n = 16) at the neonatal (presurgery) and pre-bidirectional cavopulmonary anastomosis (pre-BCPA) stages. Functional measures (fractional area change, indexed ventricular annular plane systolic excursion [iVAPSE], isovolumic acceleration [IVA], myocardial performance index, E and A velocities, tissue Doppler imaging annular velocities and STE-measured global longitudinal and circumferential strain, strain rate [SR], and early diastolic SR [EDSR]) were compared between SRV and SLV at each stage and between presurgery and pre-BCPA. RESULTS: Compared with SLV, presurgery SRV had lower circumferential strain (-10.6% vs -16.5%; P = .0002) and EDSR (1.41%/sec vs 2.13%/sec; P = .001). Pre-BCPA SRV had decreased IVA (1.2 vs 2.1 m/sec2; P = .006): longitudinal strain (-15.3% vs -19.1%; P = .001), SR (-0.97%/sec vs -1.53%/sec; P = .0001), EDSR (1.5%/sec vs 2.1%/sec; P = .001); circumferential strain (-10.6% vs -14.9%; P = .002), SR (-0.8%/sec vs -1.21%/sec; P = .0001), and EDSR (1.3%/sec vs 1.8%/sec; P = .009). SRV showed reduction of iVAPSE, IVA, s', e', a' velocities, longitudinal strain, SR, EDSR, and circumferential SR (P < .05) from presurgery to pre-BCPA, while circumferential strain was unchanged. SLV showed no significant change in these parameters during this interval. CONCLUSIONS: The progressive reduction in SRV longitudinal and circumferential function suggests that SRV may have a mechanical disadvantage from birth and progressive impairment with age.