Effect of Balloon Pulmonary Valvuloplasty on Growth of Pulmonary Annulus in Infants with Tetralogy of Fallot.

Percutaneous balloon pulmonary valvuloplasty (PBPV) is an alternative intervention in infants with Tetralogy of Fallot (TOF). It can not only improve hypoxia but also promote pulmonary annulus (PA) growth. In this study, we evaluated the effect of PBPV on PA growth in infants with TOF. To eliminate the effect of the systemic to pulmonary shunt (SPS) that may promote PA growth, we divided TOF infants into 2 groups: group A, patients who underwent PBPV with or without other SPS, and group B, patients who attempted SPS but without PBPV. Sixty patients were included, 28 patients in group A and 32 patients in group B. Age at the time of intervention in group A (range, 0.4-5.4; median 1.4 months) was lower than that in group B (range, 2.3-7.7; median 4.8 months), p-value 0.02. The body weight in group A (range, 3-5.5; median 3.7 kg) was also lower than that in group B (range 4.1-6.4; median 5.9 kg), p-value 0.02. Echocardiographic data at the mean follow-up period of 37.2 months (3-88 months) in group A and 39.6 months (6-95 months) in group B demonstrated an increase in mean PA diameter from 5.0 ± 1.3 mm to 10.2 ± 2.9 mm, p-value < 0.001 in group A; and from 6.2 ± 2 mm to 9.5 ± 2.9 mm, p-value < 0.001 in group B. The median PA z-score increased from - 3.4SD (- 3.9 to - 2.6SD) to - 1.8SD (- 2.5 to - 0.8SD), with the p-value of 0.002 in group A; and increased from - 2.9SD (- 4.5 to - 1.3SD) to - 2.7SD (- 3.6 to - 1.4SD), with the p-value of 0.73 in group B. By using the PA z-score as the absolute value, there was a statistically significant increase in the PA z-score during follow-up in group A, but not in group B. Balloon pulmonary valvuloplasty in infants with TOF can facilitate the growth of the pulmonic annulus even after eliminating the effect of the systemic to pulmonary shunt.

Mortality rate in patients with SAR-COV-2 infection treated with extracorporeal membrane oxygenator: A systematic review and meta-analysis.

BACKGROUND: Extracorporeal membrane oxygenator (ECMO) is one of the life-saving modalities for the treatment of multiple organs dysfunction, particularly the heart and the lungs. OBJECTIVE: To evaluate the benefit of ECMO for the treatment of SAR-COV-2 infection and its outcomes, complications, and mortality rate. METHODS: A comprehensive search for articles was performed using MEDLINE and SCOPUS from December 2019 to December 2020. Two independent reviewers selected eligible studies, extracted the data, assessed the quality of the studies, reviewed the full study protocols, and reported the findings according to the PRISMA protocol. The meta-analyses were performed using the Comprehensive Meta-Analysis software version 2.0. RESULTS: Pooled data from 57 studies was analyzed. There were 7,035 patients with SAR-COV-2 infection with event rate of ECMO treatment was 58.10% (95%CI: 43.70-71.20). The mortality rate was 16.66% (95%CI: 11.49-23.53). The mean mortality rate of ECMO supported patients was 35.60% (95%CI: 30.60 to 41.00). Thirty-one percent (95%CI: 24.50-38.40) of the patients had venous thromboembolic events, 30.90% (95%CI: 17.90-47.80) of the patients had ECMO circuit thrombosis, and 24.50% (95%CI: 12.50-42.40) of the patients had bleeding. In the subgroup analysis, the mortality rate was higher among patients who were treated with ECMO, the pooled odds ratio was 4.47 (95%CI: 2.39-8.35, p < 0.001), and was significantly higher in Asia with an odds ratio of 7.88 (95%CI: 2.40-25.85, p = 0.001). CONCLUSION: Mortality rate among patients who received ECMO therapy was high. A system of care, including patient selection, resource management and referral system, can impact the outcomes of ECMO therapy.

Outcomes of duct stenting and modified Blalock-Taussig shunt in cyanotic congenital heart disease with duct-dependent pulmonary circulation.

BACKGROUND: Transcatheter ductus arteriosus stenting (DS) is emerging as an alternative method to modified Blalock-Taussig shunt (MBTS) in providing pulmonary blood flow in cyanotic congenital heart disease (CCHD) with duct-dependent pulmonary circulation. OBJECTIVE: To evaluate post-procedural outcomes and survival between patients undergoing DS and MBTS. METHODS: All infants ≤ 60 days of age having CCHD with diminished pulmonary blood flow who underwent palliative procedure either with MBTS or DS at King Chulalongkorn Memorial Hospital during January 1st, 2013 and December 31th, 2017 were retrospectively reviewed. RESULTS: 98 patients were included; 34 patients underwent a transcatheter DS and 64 patients underwent MBTS. There was no significant difference in post-procedural outcomes and overall mortality rate between two groups (17.6% in MBTS group and 6.1% in DS group, p = 0.09). Single ventricle morphology was the major risk factor associated with increased mortality compared with biventricular morphology (aHR 3.9, 95% CI 1.49-10.2, p = 0.01). There was similar number of early and pre-repair additional interventions focusing on MBTS/DS patency between two groups. The MBTS group had a greater number of early interventions on PA branch stenosis related to baseline diagnosis. Risk factors associated with additional intervention were pre-existing pulmonary branch stenosis (aHR 2.54, 95% CI 1.3-4.97, p = 0.006) and body weight less than 2.5 kg (aHR 3.33, 95% CI 1.57-7.08, p = 0.003). Having pulmonic valve perforation or balloon pulmonary valvuloplasty to promote antegrade pulmonary blood flow could result in a lower number of additional interventions required before definitive repair. CONCLUSION: Duct stenting is a feasible and safe alternative to MBTS in cyanotic infants with duct-dependent pulmonary circulation. However, mortality rate was significantly higher in patients with single ventricle that required careful follow-up after procedure.

Long-term course after pediatric right ventricular outflow tract reconstruction.

OBJECTIVES: Valved homografts are commonly used for right ventricular outflow tract reconstruction. However, despite good early results, they lack durability. This study was designed to compare single-center results of implantation of 3 types of right ventricular outflow tract conduit, in terms of patient survival, graft failure, reoperation, and risk factors for reoperation. METHODS: One hundred and forty-three pediatric patients who underwent right ventricular outflow tract conduit implantation between January 2006 and December 2018 were reviewed. We stratified conduits by aortic, pulmonic homograft, and Contegra; 74 aortic homografts, 61 pulmonic homografts, and 8 Contegra conduits were implanted. Median age at implantation was 3 years. The primary diagnosis was truncus arteriosus in 41.3%. We analyzed the role of sex, age, diagnosis, and graft size. Endpoints included freedom from graft failure, freedom from reoperation, and survival. RESULTS: The survival rate was 83.2% at 10 years. Freedom from graft failure at 2, 5, and 10 years was 100%, 97.9%, and 63.4%, respectively. Freedom from reoperation was 85.8% for pulmonic homografts and 74.9% for aortic homografts at 10 years, and 100% for Contegra at 6 years. Multivariable analysis identified conduit diameter <18 mm as a risk factor for reoperation (hazard ratio: 3.16, 95% confidence interval: 1.38-7.23, p = 0.007). CONCLUSION: Homograft valves used for right ventricular outflow tract reconstruction provided excellent long-term durability and late survival. The only factor that adversely affected graft longevity was small graft size (diameter <18 mm). Reoperation for conduit failure was not significantly different among the groups.

Thrombocytopenia in Moderate- to High-Risk Sutureless Aortic Valve Replacement.

BACKGROUND: This study aimed to compare preliminary data on the outcomes of sutureless aortic valve replacement (SU-AVR) with those of aortic valve replacement (AVR). METHODS: We conducted a retrospective study of SU-AVR in moderate- to high-risk patients from 2013 to 2016. Matching was performed at a 1:1 ratio using the Society of Thoracic Surgeons predicted risk of mortality score with sex and age. The primary outcome was 30-day mortality. The secondary outcomes were operative outcomes and complications. RESULTS: A total of 277 patients were studied. Ten patients (50% males; median age, 81.5 years) underwent SU-AVR. Postoperative echocardiography showed impressive outcomes in the SU-AVR group. The 30-day mortality was 10% in both groups. In our study, the patients in the SU-AVR group developed postoperative thrombocytopenia. Platelet counts decreased from 225×103/µL preoperatively to 94.5, 54.5, and 50.1×103/µL on postoperative days 1, 2, and 3, respectively, showing significant differences compared with the AVR group (p=0.04, p=0.16, and p=0.20, respectively). The median amount of platelet transfusion was higher in the AVR group (12.5 vs. 0 units, p=0.052). CONCLUSION: There was no difference in the 30-day mortality of moderate- to high-risk patients depending on whether they underwent SU-AVR or AVR. Although SU-AVR is associated with favorable cardiopulmonary bypass and cross-clamp times, it may be associated with postoperative thrombocytopenia.

Very late presentation of anomalous origin of the left coronary artery from the pulmonary artery: case report.

BACKGROUND: Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary anomaly. The enlarged right coronary artery provides retrograde collaterals to supply the left ventricle then preferentially directs into the lower pressure pulmonary artery system causing coronary steal phenomenon. Few patients who survive through adulthood without surgery must have abundant, well-formed functioning collaterals with adequate perfusion of the left ventricle. We present the oldest reported patient with ALCAPA to undergo corrective surgery. CASE PRESENTATION: A 79-year-old woman presented with a 3-months history of worsening shortness of breath and orthopnea. Physical examination discovered a soft continuous murmur at the left upper chest. Transthoracic echocardiography demonstrated an unusual, tubular-like structure inside the interventricular septum with a turbulent flow from color Doppler. Moreover, there was a severe mitral regurgitation from posterior mitral leaflet restriction associated with ventricular remodeling in combination with mitral annular dilatation. Coronary angiography and coronary computed tomography angiography established the diagnostic hallmark of ALCAPA syndrome. Stress cardiovascular magnetic resonance perfusion imaging demonstrated no myocardial ischemia suggesting adequate collateral circulation. Remarkably, there was a left coronary ostial stenosis, which served as a protective mechanism against myocardia ischemia by limiting the steal effect. The patient successfully underwent the ligation of anomalous artery at its origin in combination with bioprosthetic mitral valve replacement. Her postoperative course was uneventful. CONCLUSIONS: This case utilized multimodality imaging for delineating the course of abnormal vessels and helping to formulate therapeutic decision.

Beating heart as an alternative for closure of secundum atrial septal defect.

We repaired secundum atrial septal defect in 135 consecutive patients from February 2003 to December 2010. There were 98 females and 37 males, with a mean age of 22.92 ± 17.46 years (range, 3-55 years). To prevent myocardial dysfunction and systemic embolism caused by the conventional technique, the operation was performed with a beating heart under cardiopulmonary bypass in 63 cases, and compared the data retrospectively with cases treated under aortic crossclamping, to determine the safety of the beating-heart technique and to evaluate risk factors for embolism in stroke patients. Patient age and size of defect were similar in both groups. There was no death and no residual shunt in either group. The mean cardiopulmonary bypass time was 36.84 ± 9.8 min in the beating-heart group and 43.13 ± 16.7 min in the crossclamp group. The ejection fraction and the incidence of postoperative arrhythmia were similar in both groups. There were no differences in blood products transfused, intensive care unit stay, hospital stay, or perioperative morbidity. In our experience, the results of the beating-heart technique were not different from the conventional technique.

Pharmacokinetic and pharmacodynamic variation associated with VKORC1 and CYP2C9 polymorphisms in Thai patients taking warfarin.

We investigated the influence of genetic polymorphisms of CYP2C9 and VKORC1 genotypes on the pharmacokinetics and pharmacodynamics of warfarin and established an equation for predicting the maintenance dose of warfarin in the Thai population using genetic and non-genetic factors. The CYP2C9*2, CYP2C9*3, VKORC1 C1173T and VKORC1 G-1639A genotypes were detected by realtime PCR using fluorogenic hybridization probes. The associations between genetic and demographic factors with respect to warfarin dosage were analyzed. CYP2C9 polymorphisms affect warfarin metabolism as shown by a significant difference in warfarin clearance, whereas VKORC1 genotypes cause a significant difference in warfarin sensitivity index (INR:Cp). The mean weekly warfarin dose was significantly different among different VKORC1 and CYP2C9 genotypes. Patients with the VKORC1 BB haplotype and CYP2C9*1/*1 required about twice the warfarin dose compared to those with the VKORC1 AA haplotype and CYP2C9*1/*1. Using stepwise multiple linear regression, clinical factors (age and weight) and genetic factors (CYP2C9 and VKORC1) could explain about 53.8% of the variance of the warfarin maintenance dose. CYP2C9 and VKORC1 genotypes played an important role in the inter-individual variation in warfarin maintenance dose in a Thai population.

Balloon pulmonary valvuloplasty in tetralogy of Fallot: effects on growth of pulmonary annulus and transannular patch.

BACKGROUND: Balloon pulmonary valvuloplasty and its benefit on the growth of pulmonary annulus and pulmonary artery in tetralogy of Fallot (TOF) patients remains controversial. The purpose ofthe present study was to determine the growth of pulmonary valve annulus and pulmonary artery and to evaluate the need of transannular patch during total surgical correction in patients with tetralogy of Fallot (TOF) after balloon pulmonary valvuloplasty. MATERIAL AND METHOD: Fifty-one severely hypoxic TOF patients, who underwent balloon dilatation ofpulmonary valve, were included in the present study. The clinical outcomes, oxygen saturation, and echocardiographic parameters before and after balloon dilatation were analyzed. RESULTS: There were 33 males and 18females. The mean age was 3 years 5 months old (range, I month-15 years 8 months old). The mean oxygen saturation increasedfrom 73.9 +/- 9.1 to 84.8 +/- 6.7% immediately after the procedure (p-value < 0.05). There was no serious procedural-related complication. At the mean follow-up period of 2 years and 4 months, the mean Z-score of pulmonary annulus size increased from -2.56 SD to -1.87 SD (p-value < 0.05) and the right pulmonary artery size from -0.29 SD to + 0.46 SD (p-value < 0.05). Thirty-seven patients (66.1%) underwent corrective surgery. Pulmonary transannular patch was performed in 11 of37 patients (29.7%). CONCLUSION: Pulmonary valve dilatation in patients with TOF is safe. It promotes the growth ofthe pulmonary valve annulus and pulmonary artery and may decrease the need of transannular patch at the time of surgical correction.

Short-term outcome of PDA ligation in the preterm infants at King Chulalongkorn Memorial Hospital, Thailand.

BACKGROUND: Failure of the ductus arteriosus to close after medical treatment is usually associated with many severe cardio-respiratory morbidities. Therefore, surgical ligation of symptomatic PDA is indicated in preterm newborn infants who do not respond or have contraindication of medical treatment. OBJECTIVE: To report the short-term outcomes of PDA ligation in preterm infants at a tertiary care hospital in Thailand. MATERIAL AND METHOD: Medical records of 42 preterm infants who underwent surgical ligation of PDA at King Chulalongkorn Memorial Hospital were reviewed All of the infants had symptomatic PDA that failed to respond to medical treatment or had a contraindication to indomethacin or ibuprofen. Surgical ligation of PDA was performed under general anesthesia. Morbidity and mortality occurring during hospitalization were reported. RESULTS: There were 42 preterm infants in the present study. All of them had large PDA with intractable congestive heart failure. Mean + SD of birth weight and gestational age were 1206 +/- 567 grams and 28.7 +/- 3.6 weeks respectively. Mean +/- SD of the infants' weight and age at the time of surgery were 1089 +/- 549 grams and 17.5 +/- 12 days respectively. Data on the size of PDA was available on 21 preterm infants. Their ductus diameter (Mean +/- SD) was 3.1 +/- 1.1 mm. All infants were successfully extubated after PDA ligation. Twelve events of complications occurred in 11 infants (26.7%). All of the complications were of mild degree and resolved within a few days except one infant with left phrenic nerve injury that needed surgical plication of the diaphragm. Two infants died at 37 and 160 days after surgery and the latter infant developed IVH grade IV on the 15th day postoperatively. These complications were probably not related to PDA ligation. CONCLUSION: PDA ligation was performed successfully on 42 preterm infants who had medical failure or had contraindication to medical treatment. Cardio-respiratory illnesses improved significantly after ligation. Two infant mortalities were not related to the procedure. Overall complication of surgery was 26.7% and resolved without sequelae.

Bicuspidized pulmonary homograft for truncus arteriosus repair.

Primary repair is preferable to palliation in infants with truncus arteriosus. At our institute, an appropriately small homograft valved conduit is not available for every patient; a bicuspidized pulmonary valve homograft is an alternative. Between December 1996 and August 2005, 24 patients aged 28 days to 21 months with truncus arteriosus underwent primary repair with a homograft valved conduit; bicuspidized homografts were used in 15 of them. In the 18 (75%) patients who survived to hospital discharge, 5-year survival was 94% (75% for tricuspid homografts and 100% for bicuspidized homografts, which was not significantly different). Freedom from reoperation or balloon angioplasty in all 18 survivors was 89% at 5 years. Freedom from reoperation in tricuspid and bicuspidized homograft groups at 5 years was 67% and 100%, respectively; the difference was not statistically significant. Bicuspidized homografts worked as well as tricuspid conduits in the intermediate term. The remodeled homografts showed excellent hemodynamic characteristics and appear to be a reasonable alternative when an appropriate size of valved homograft is unavailable.