Surgery for doubly committed ventricular septal defects.

OBJECTIVES: Doubly committed ventricular septal defects (VSDs) account for up to almost one-third of isolated ventricular septal defects in Asian countries, compared with only 1/20th in western populations. In our surgical experience, this type of defect accounted for almost three-quarters of our practice. To date, patch closure has been considered the gold standard for surgical treatment of these lesions. Our objectives are to evaluate the indications and examine the outcomes of surgery for doubly committed VSDs. METHODS: Between October 2013, when our service of paediatric cardiac surgery was opened, and December 2014, 24 patients were referred for surgical closure of VSDs. Among them, 17 patients (71%), with the median age of 6 years, ranging from 2 to 9 years, and with a median body weight of 19 kg, ranging from 11 to 56 kg, underwent surgical repair for doubly committed defects. In terms of size, the defect was considered moderate in 4 and large in 13. Aortic valvular regurgitation (AoVR) was present in 11 patients (65%) preoperatively, with associated malformations found in 14 (82%), with 5 patients (29%) having two or more associated defects. RESULTS: After surgery, there was trivial residual shunting in 2 patients (12%). AoVR persisted in 6 (35%), reducing to trivial in 5 (29%) and mild in 1 (6%). Mean stays in the intensive care unit and hospital were 2.6 ± 1.2 days, ranging from 2 to 7 days, and 6.8 ± 0.8 days, ranging from 6 to 9 days, respectively. The mean follow-up was 14 ± 4 months, ranging from 6 to 20 months, with no early or late deaths and without clinical deterioration. CONCLUSIONS: The incidence of doubly committed lesions is high in our experience, frequently associated with AoVR and other associated malformation. Early detection is crucial to prevent further progression of the disease. Patch closure remains the gold standard in management, not least since it allows simultaneous repair of associated intracardiac defects.

An Unusual Type of Totally Anomalous Pulmonary Venous Connection to the Superior Cavoatrial Junction.

A neonate with cyanosis at birth was found to have a rare type of totally anomalous pulmonary venous connection. The pulmonary veins entered a confluence posterior to the left atrial wall, which drained into the right superior cavoatrial junction. There were no other major structural defects and no evidence of isomerism. Because of the severe cyanosis, and the restrictive nature of the interatrial communication, we performed balloon atrioseptostomy to improve oxygenation. We then achieved successful surgical repair when the baby was aged 7 months.

Screening of SMAD7 in Malay patients with ventricular septal defect.

Ventricular septal defect (VSD) is the most common form of cardiac malformations accounting approximately 20% of all congenital heart defects. SMAD7 is an inhibitory protein that antagonizes the signalling of TGF-ß family member and has been found in the development and function of mouse heart models. This study aims to screen and identify the polymorphisms of SMAD7 exonic regions in Malay population with VSD. Peripheral blood samples were collected and extracted from 30 clinically diagnosed VSD patients. PCR amplification was performed using 12 sets of designed primers encompassing seven exons of SMAD7. Re-sequencing was conducted to characterize the polymorphisms of SMAD7. Observed polymorphisms were then genotyped in 30 healthy individuals using both re-sequencing and allele-specific PCR techniques. A total of 10 variants were identified in the patient population located in the upstream (rs7236774), exonic (rs368427729, rs145686330, rs3764482, rs3809922, rs780863704 and rs3809923), intronic (rs3736242) and 3'UTR regions (rs375444823 and rs16950113). No significant difference of genotype and allele frequency was observed among these SNPs. Two synonymous variants (rs3809922 and rs3809923) were found in complete linkage disequilibrium (r2=1.0) with each other indicate a strong correlation of these SNPs. The identification of these SNPs provides a new perspective of the VSD causation.

Normothermia for pediatric and congenital heart surgery: an expanded horizon.

Cardiopulmonary bypass (CPB) in pediatric cardiac surgery is generally performed with hypothermia, flow reduction and hemodilution. From October 2013 to December 2014, 55 patients, median age 6 years (range 2 months to 52 years), median weight 18.5 kg (range 3.2-57 kg), underwent surgery with normothermic high flow CPB in a new unit. There were no early or late deaths. Fifty patients (90.9%) were extubated within 3 h, 3 (5.5%) within 24 h, and 2 (3.6%) within 48 h. Twenty-four patients (43.6%) did not require inotropic support, 31 (56.4%) received dopamine or dobutamine: 21 ≤5 mcg/kg/min, 8 5-10 mcg/kg/min, and 2 >10 mcg/kg/min. Two patients (6.5%) required noradrenaline 0.05-0.1 mcg/kg/min. On arrival to ICU and after 3 and 6 h and 8:00 a.m. the next morning, mean lactate levels were 1.9 ± 09, 2.0 ± 1.2, 1.6 ± 0.8, and 1.4 ± 0.7 mmol/L (0.6-5.2 mmol/L), respectively. From arrival to ICU to 8:00 a.m. the next morning mean urine output was 3.8 ± 1.5 mL/kg/h (0.7-7.6 mL/kg/h), and mean chest drainage was 0.6 ± 0.5 mL/kg/h (0.1-2.3 mL/kg/h). Mean ICU and hospital stay were 2.7 ± 1.4 days (2-8 days) and 7.2 ± 2.2 days (4-15 days), respectively. In conclusion, normothermic high flow CPB allows pediatric and congenital heart surgery with favorable outcomes even in a new unit. The immediate post-operative period is characterized by low requirement for inotropic and respiratory support, low lactate production, adequate urine output, minimal drainage from the chest drains, short ICU, and hospital stay.

Device closure of patent ductus arteriosus in Marfan patients: safety and effect on the aortic root diameter.

OBJECTIVES: There is little evidence in the medical literature about safety of PDA device closure and its effects on aortic root diameter in Marfan patients. We reported on nine Marfan patients whose ducts were occluded by coil or Amplatzer Duct Occluder. PATIENTS AND INTERVENTIONS: Two patients had aneurismal type E ducts which were closed by a single coil, respectively. The others had conical ducts for which even Amplatzer occluder, stiff, or double coils were used. RESULTS: No untoward consequence was found during a median follow up period of 18.5 months (range 3 months to 6.33 years). Two patients had small residual shunts. The observed change in the mean ratio of aortic root diameter to its estimated value was statistically insignificant in seven patients who had complete data on their aortic root diameter before PDA closure and during the follow up. CONCLUSIONS: We concluded that PDA device closure in Marfan patients is safe. Risk of residual shunt is higher even after closure of small ducts.

Prevalence of beta-2 adrenergic receptor (beta 2 AR) polymorphisms and its influence on a model used to assess endothelial function using pulse wave analysis (PWA).

BACKGROUND: Pulse wave analysis (PWA) combined with beta(2)-agonist challenge has recently been used to assess endothelial function. beta-2 adrenergic receptor (beta(2)AR) polymorphisms may affect response to beta(2)-agonist. We determined whether beta(2)AR polymorphisms influence endothelial response in our model using PWA and salbutamol. METHODS: 388 healthy Malay subjects (177 males, 211 females) were genotyped for 5 functionally important single nucleotide polymorphisms (SNPs) of beta(2)AR; 298 subjects proceeded with assessment of endothelial function. The parameter augmentation index (AIx) was recorded non-invasively using SphygmoCor. Recording of AIx at baseline was followed by administration of 500 microg sublingual glyceryl trinitrate (GTN). AIx recordings were repeated at 3, 5, 10, 15 and 20 min post-GTN. Subjects then inhaled 400 microg of salbutamol before AIx recordings at 5 min intervals up to 20 min. Maximum changes in AIx after GTN and salbutamol represented endothelium independent and endothelium dependent vasodilatation (EDV) respectively. RESULTS: Allele frequencies of mutated Gly16, Glu27, Ile164, -20C and -47C were 47%, 6.8%, 0%, 30% and 9.3% respectively. No significant differences in EDV were noted between genotype groups of each studied SNPs. CONCLUSIONS: Assessment of endothelial function using PWA and salbutamol was not influenced by beta(2)AR polymorphisms.

Arterial compliance and vitamin E blood levels with a self emulsifying preparation of tocotrienol rich vitamin E.

The tocotrienol vitamin E has potent antioxidant property, however absorption is low due to high lipid solubility. A self emulsifying preparation of tocotrienol rich vitamin E (SF-TRE) had been reported to increase their bioavailability. This randomized, placebo controlled, blinded end point clinical study aimed to determine the effects of 50, 100 and 200 mg daily of SF-TRE and placebo for two months on arterial compliance and vitamin E blood levels. Assessment of arterial compliance by carotid femoral pulse wave velocity (PWV) and augmentation index (AI), plasma vitamin E, serum total cholesterol and low density lipoprotein cholesterol were taken before and after 2 months' treatment in 36 healthy males. Un-supplemented tocotrienol levels were low, after treatment, all SF-TRE treated groups had significantly higher plasma alpha, delta and delta tocotrienol concentrations compared to placebo. Augmentation index change from baseline to end of treatment for groups placebo, 50, 100, and 200 mg were 2.22+/-1.54, -6.59+/-2.84, -8.72+/-3.77, and -6.27+/-2.67% respectively (p=0.049, 0.049, and 0.047 respectively). Groups 100 and 200 mg showed significant improvement after treatment with pulse wave velocity reductions of 0.77 m/s and 0.65 m/s respectively (p=0.007 and p=0.002). There was no effect of SF-TRE on serum lipids. We conclude that there was a trend towards improvement in arterial compliance with 2 months' of SF-TRE.

Method optimization on the use of postocclusive hyperemia model to assess microvascular function.

INTRODUCTION: Recent development had allowed non-invasive assessment of microvascular function in vivo; however, the method has not been fully optimized and standardized. In this study, we aimed to characterize the "effective" occlusion duration needed to elicit sufficient postocclusive hyperemia (PORH) responses in forearm skin using laser Doppler fluximetry (LDF), in subjects with differing age, gender and menstrual phases. MATERIALS AND METHODS: A total of 120 healthy subjects were studied (20 subjects each in the age ranges of 21-30, 31-40, 41-50 for both genders). Male subjects were randomized to receive 1, 2 or 3 min occlusion on three study days. Females attended six study days: the first three days (with different occlusion times) were performed during low estrogenic phase of menstrual cycle and subsequent three visits were done during high estrogenic phase. Skin perfusion was measured before, during and after occlusion using LDF. The magnitude and temporal courses of PORH were expressed as PORH max (absolute maximal increase in hyperemia perfusion) and Tp (time-to-peak), respectively. RESULTS: For PORH max analysis, the occlusion duration should be applied based on one's age, gender and menstrual phase. The PORH responses were more consistent during high estrogenic phase with 2 min found as the "effective" occlusion duration in all female groups. For Tp analysis, 3 min occlusion produced the significant change in all age ranges for both genders irrespective of menstrual phase. CONCLUSION: This study revealed that for assessment of microvascular function using PORH+LDF model, the occlusion duration for PORH max is influenced by age, gender and menstrual phase. Measurement based on Tp is however independent of these factors.

Arrhythmogenic right ventricular cardiomyopathy in an 11-year-old girl and typical echocardiographic features.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare entity that affects children as well as adults. This is a genetic disorder that can be inherited and whose hallmark is fibrofatty replacement of ventricular muscle, especially of the right side, with ventricular arrhythmias and progressive heart failure. We describe a case of an 11-year-old Saudi girl with ARVC and the echocardiographic characteristics that had been highlighted by the Taskforce for ARVC, and we suggest that a concurrent criterion be added to aid further echo identification in children.

Sildenafil as treatment for Human Immunodeficiency Virus-related pulmonary hypertension in a child.

Human Immunodeficiency Virus (HIV)-related pulmonary hypertension is a relatively rare disease that can affect HIV sufferers. This is almost always associated with a poor outcome and death. An 18 month-old girl, probably the youngest on record, was diagnosed to have pulmonary hypertension (PHT) and retrospectively found to have HIV infection. Sildenafil was used to control her PHT and she remains alive even after 2 years.