Aortic Root Dilatation Measured by Cardiac Magnetic Resonance in Patients with Repaired Tetralogy of Fallot.

BACKGROUND: Aortic root dilatation (AoD) frequently occurs following repaired tetralogy of Fallot (rTOF). The objective of this study was to assess aortic dimensions, investigate the prevalence of AoD, and identify predictors of AoD in rTOF patients. METHODS: A cross-sectional retrospective study was conducted in repaired TOF patients from 2009 to 2020. Aortic root diameters were measured by cardiac magnetic resonance (CMR). Severe AoD of the aortic sinus (AoS) was defined as a Z-score (z) of >4, reflecting a mean percentile ≥99.99%. RESULTS: Two hundred forty-eight patients, with a median age of 28.2 years (10.2-65.3 years), were included in the study. The median age at the time of repair was 6.6 years (0.8-40.5 years) and the median interval between the repair and CMR study was 18.9 years (2.0-54.8 years). The prevalence of severe AoD was found to be 35.2% when defined by an AoS z greater than 4 and 27.6% when defined by a AoS diameter ≥40 mm, respectively. A total of 101 patients (40.7%) had aortic regurgitation (AR), with 7 patients (2.8%) having moderate AR. Multivariate analysis revealed that severe AoD was only associated with the left ventricular end diastolic volume index (LVEDVi) and a longer duration after repair. The age at the time of repair for TOF was found not to be correlated with the development of AoD. CONCLUSIONS: After repair of TOF, severe AoD was found to be prevalent, but no fatal complications were observed in our study. Mild AR was also commonly observed. Larger LVEDVi and a longer duration after repair were identified as factors associated with the development of severe AoD. Therefore, routine monitoring of AoD is recommended.

Major infections following pediatric cardiac surgery pre- and post-CLABSI bundle implementation.

Background: Postoperative infection contributes to the worsening of congenital cardiac surgery (CCS) outcomes. Surgical site infection (SSI), bloodstream infection (BSI) and ventilator associated pneumonia (VAP) are common. An additional bundle of preventive measures against central-line associated bloodstream infection (CLABSI) bundle was implemented in April 2019. Objectives: To compare the incidence of major infections after pediatric CCS before and after the implementation of the CLABSI bundle and to identify risk factors for major infections. Methods: We conducted a single-center, retrospective study to assess the incidence of major infections including bloodstream infection (BSI), surgical site infection (SSI), and ventilator-associated pneumonia (VAP) after pediatric CCS one year before and after implementation of the CLABSI bundle during April 2018-March 2020. The demographics and outcomes of the patients were explored, and risk factors for major infections were identified using multivariate analysis. Results: A total of 548 children (53% male) underwent CCS with a median age of 1.9 years (range 0.01-17.5 years). The median Aristotle Basic Complexity score was 7.1 (range 3-14.5). The CLABSI bundle was applied in 262 patients. Overall mortality was 5.5%. 126 patients (23%) experienced major postoperative infections. During the year after the implementation of the CLABSI bundle, BSI was reduced from 8.4% to 3.1% (p = 0.01), with a smaller reduction in VAP (21% to 17.6%; p = 0.33). The incidence of SSI was unchanged (1.7% to 1.9%; p = 0.77). The independent risk factors for major infections were age at surgery <6 months (p = 0.04), postoperative ventilator usage >2 days (p < 0.01), central line usage >4 days (p = 0.04), and surgery during the pre-CLABSI bundle period (p = 0.01). Conclusion: Following the implementation of the CLABSI prevention package in our pediatric CCS unit, the incidence of BSI was significantly reduced. The incidence of VAP tended to decrease, while the SSI was unchanged. Sustainability of the prevention package through nurse empowerment and compliance audits is an ongoing challenge.

Risk factors and long-term outcomes after tetralogy of Fallot repair at an Asian tertiary referral center.

BACKGROUND: Tetralogy of Fallot is the most common type of cyanotic congenital heart disease. More postoperative tetralogy of Fallot patients grow up than in the past, and these patients need to be followed-up. OBJECTIVE: To investigate the survival and long-term outcomes of patients who underwent total repair of tetralogy of Fallot, and to identify the risk factors for reoperation with pulmonic valve replacement. METHOD: A total of 403 patients who underwent total tetralogy of Fallot repair at our center during 1997 to 2016 were retrospectively included. Demographic, clinical, treatment, outcome, and follow-up data were collected and analyzed. RESULTS: Median age and body weight at the time of tetralogy of Fallot repair was 4.41 years (range: 0.85-55.28) and 13.58 kg (range: 5.5-68), respectively. The median follow-up was 9.0 years, and overall mortality was 3.2%. The actuarial survival rates at 10 and 20 years were 96.4% and 95.2%, respectively, and the freedom from pulmonic valve replacement was 93.4% and 57.4%, respectively. The median time to indicate pulmonic valve replacement was 13.9 years (range: 6.2-20.5). Multivariate analysis revealed transannular patch technique (hazard ratio: 3.023, 95% confidence interval: 1.34-6.83; p = 0.008) and palliative shunt (hazard ratio: 2.39, 95% confidence interval: 1.16-4.91; p = 0.018) to be independent risk factors for reoperation with pulmonic valve replacement. CONCLUSION: The rates of overall survival and freedom from pulmonic valve replacement were both high in this study, and both were comparable to the rates reported from other studies. Overall mortality was as low as 3.47%. The need for a transannular patch or palliative shunt should be considered risk factors for a consequent reoperation.

Contemporary outcomes and mortality risks of Ebstein anomaly: A single-center experience in Thailand.

BACKGROUND: The increasing number of patients with Ebstein anomaly (EA) surviving into adulthood implies improvements in the treatments for the complex lesion. We revisited the clinical outcomes of patients with EA to demonstrate their "real world" survival. OBJECTIVES: To identify the survival and predictors of mortality in patients with EA who underwent medical or surgical management in the present era. METHODS: All patients who had EA with atrioventricular concordance between 1994 and 2016 were retrospectively reviewed. Baseline characteristics, initial echocardiographic findings, treatments, and outcomes were explored. The survival analysis was performed at the end of 2017. A multivariate analysis was used to assess mortality risks. RESULTS: A total of 153 patients (25.4 ± 20.4 years, 60% female) were analyzed. Of these, 89 patients had been diagnosed with EA in childhood. During the follow-up [median time of 5.2 years (3 days-23.5 years)], 32 patients (20.9%) died due to major cardiac adverse events. The overall survival at 1, 5, and 10 years were 89%, 82.2%, and 79%, respectively. Of the total 153 patients, 64 patients underwent at least one surgical intervention [median age of 17 years (1 day-64.4 years)]. The survival at 1, 5, and 10 years were 87.5%, 82.4%, and 77.7%, respectively, in patients with EA surgery. This survival is comparable to the survival of 89 nonoperated patients with EA: 89.9%, 87.5%, and 81.8%, at 1, 5, and 10 years, respectively. The significant predictors of mortality were: age at diagnosis ≤2 years, tricuspid valve (TV) z-score >3.80, TV displacement >19.5 mm/m2 , presence of severe tricuspid regurgitation, and absence of forward flow across the pulmonic valve at the initial diagnosis. CONCLUSION: Patients with EA had a moderately good survival in this era. In this paper, we report five simple predictors of death in this patient population.

Contemporary survival of patients with pulmonary arterial hypertension and congenital systemic to pulmonary shunts.

OBJECTIVE: To compare survival of patients with newly diagnosed pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) according to various clinical classifications with classifications of anatomical-pathophysiological systemic to pulmonary shunts in a single-center cohort. METHODS: All prevalent cases of PAH-CHD with hemodynamic confirmation by cardiac catheterization in 1995-2015 were retrospectively reviewed. Patients who were younger than three months of age, or with single ventricle following surgery were excluded. Baseline characteristics and clinical outcomes were retrieved from the database. The survival analysis was performed at the end of 2016. Prognostic factors were identified using multivariate analysis. RESULTS: A total of 366 consecutive patients (24.5 ± 17.6 years of age, 40% male) with PAH-CHD were analyzed. Most had simple shunts (85 pre-tricuspid, 105 post-tricuspid, 102 combined shunts). Patients with pre-tricuspid shunts were significantly older at diagnosis in comparison to post-tricuspid, combined, and complex shunts. Clinical classifications identified patients as having Eisenmenger syndrome (ES, 26.8%), prevalent left to right shunt (66.7%), PAH with small defect (3%), or PAH following defect correction (3.5%). At follow-up (median = 5.9 years; 0.1-20.7 years), no statistically significant differences in survival rate were seen among the anatomical-pathophysiological shunts (p = 0.1). Conversely, the clinical classifications revealed that patients with PAH-small defect had inferior survival compared to patients with ES, PAH post-corrective surgery, or PAH with prevalent left to right shunt (p = 0.01). Significant mortality risks were functional class III, age < 10 years, PAH-small defect, elevated right atrial pressure > 15 mmHg, and baseline PVR > 8 WU•m.2. CONCLUSION: Patients with PAH-CHD had a modest long-term survival. Different anatomical-pathophysiological shunts affect the natural presentation, while clinical classifications indicate treatment strategies and survival. Contemporary therapy improves survival in deliberately selected patients.

Stress perfusion magnetic resonance imaging to detect coronary artery lesions in children.

BACKGROUND: Stress perfusion cardiovascular magnetic resonance (CMR) is used widely in adult ischemic heart disease, but data in children is limited. We sought to evaluate feasibility, accuracy and prognostic value of stress CMR in children with suspected coronary artery disease (CAD). METHODS: Stress CMR was reviewed from two pediatric centers over 5 years using a standard pharmacologic protocol. Wall motion abnormalities, perfusion deficits and late enhancement were correlated with coronary angiogram (CAG) when available, and clinical status at 1 year follow-up for major adverse cardiovascular events (MACE; coronary revascularization, non-fatal myocardial infarction and death due to CAD) was recorded. RESULTS: Sixty-four stress perfusion CMR studies in 48 children (10.9 ± 4.8 years) using adenosine; 59 (92%) and dipyridamole; 5 (8%), were reviewed. Indications were Kawasaki disease (39%), post arterial switch operation (12.5%), post heart transplantation (12.5%), post anomalous coronary artery repair (11%), chest pain (11%), suspected myocarditis or CAD (3%), post coronary revascularization (3%), and others (8%). Twenty-six studies were performed under sedation. Of all studies performed, 66% showed no evidence of ischemia or infarction, 28% had perfusion deficits and 6% had late gadolinium enhancement (LGE) without perfusion deficit. Compared to CAG, the positive predictive value (PPV) of stress CMR was 80% with negative predictive value (NPV) of 88%. At 1 year clinical follow-up, the PPV and NPV of stress CMR to predict MACE were 78 and 98%. CONCLUSION: Stress-perfusion CMR, in combination with LGE and wall motion-analysis is a feasible and an accurate method of diagnosing CAD in children. In difficult cases, it also helps guide clinical intervention by complementing conventional CAG with functional information.

Evaluation of single right atrial volume and function with magnetic resonance imaging in children with hypoplastic left heart.

BACKGROUND: Standardized methods to evaluate atrial properties in single ventricles are lacking. OBJECTIVE: To determine the feasibility of quantifying right atrial volumes and function in hypoplastic left heart using MRI. MATERIALS AND METHODS: We studied 15 infants with hypoplastic left heart prior to Glenn surgery (mean age 4.2 months [standard deviation 0.3]) who underwent cardiac MRI with evaluation of atrial volumes and emptying fraction using monoplane two-chamber, monoplane four-chamber, and biplane methods, all of which were compared to the atrial short-axial oblique stack method. We compared atrial end-diastolic volume, end-systolic volume and emptying fraction among these methods. We analyzed reproducibility of the methods using Bland‒Altman plots. RESULTS: Both four-chamber and biplane methods showed high correlations for atrial end-diastolic volume (r = 0.7 and r = 0.8, respectively; P < 0.01) and end-systolic volume (r = 0.8 and r = 0.9, respectively; P < 0.01) with small mean differences (-0.2 ± 2.9 standard deviation [SD] ml and -0.8 ± 1.6 ml, respectively, for atrial end-diastolic volume and -0.8 ± 1.5 ml and -0.9 ± 0.9 ml, respectively, for atrial end-systolic volume). The short-axial oblique method was the most reproducible, followed by the four-chamber method. CONCLUSION: MRI assessment of atrial volume and function is feasible in hypoplastic left heart and might provide further insight into single-ventricle mechanics.

Increased common atrioventricular valve tenting is a risk factor for progression to severe regurgitation in patients with a single ventricle with unbalanced atrioventricular septal defect.

OBJECTIVE: Significant atrioventricular valve regurgitation (AVVR) increases mortality in patients with unbalanced atrioventricular septal defects (uAVSDs) and a single ventricle. We tested the hypothesis that abnormal leaflet tethering is associated with progressive AVVR in patients with a single ventricle with uAVSD. METHODS: We retrospectively reviewed the initial presentation and prebidirectional cavopulmonary anastamosis echocardiograms of 46 consecutive patients with uAVSD with single ventricle palliation. AVVR was graded as moderate to severe if the sum of vena contracta width to dominant valve annulus ratio was ≥ 0.33. We measured tenting height, annular to leaflet angle and annular diameter, indexed to patient size where appropriate. Multivariate analysis of variables to predict progressive AVVR was performed. RESULTS: At follow-up of 3.3 ± 2.4 years, 24 patients had mild AVVR (Group A) and 22 had moderate to severe AVVR. Overall mortality was 6%, whereas 10 had valve repair/replacement surgery. Of 22 patients with severe AVVR at follow-up, 9 had severe AVVR at initial presentation (Group B), whereas 13 had mild AVVR at presentation but developed severe AVVR at their prebidirectional cavopulmonary anastamosis echocardiogram (Group C). Group A patients had a smaller tenting height at initial presentation compared with patients in Group B and Group C, and also had early progressive reduction of indexed tenting height (P < .01). An absolute tenting height >6 mm (odds ratio, 6.6; 95% confidence interval, 1.1-39.0; P = .03) at the initial echocardiogram was identified as an independent predictor of subsequent severe AVVR. CONCLUSIONS: Early leaflet tethering is predictive of subsequent AVVR in patients with a single ventricle with uAVSD. Patients with competent AVV had progressive reduction in the degree of leaflet tethering, whereas patients with AVVR did not. This may represent an important adaptive process to maintain valve competency in uAVSD.

Tricuspid regurgitation in hypoplastic left heart syndrome: mechanistic insights from 3-dimensional echocardiography and relationship with outcomes.

BACKGROUND: Our purpose was to test the following hypotheses: (1) patients with hypoplastic left heart syndrome who develop significant tricuspid regurgitation (TR) or require tricuspid valve (TV) surgery in the medium term have detectable TV abnormalities by 3-dimensional echocardiography (3DE) prestage 1 palliation and (2) TR is associated with reduced survival and increased TV intervention. METHODS AND RESULTS: Infants were prospectively studied with 3DE and 2DE prestage 1 and followed up for the end points of TR, TV surgery, transplantation, or death. From prestage 1 3DE, spatial coordinates of TV annulus and leaflets were extracted; annulus size, leaflet area, prolapse volume, tethering volume, bending angle, and papillary muscle angle were measured. TR was assessed prestage 1 and at latest follow-up. Of 70 patients, 62 (88.6%) had mild or less TR and 8 (11.4%) had moderate or greater TR prestage 1. Prestage 1 tethering volume correlated to leaflet area (r=0.736; P<0.001), annulus area (r=0.651; P<0.001), right ventricular end-diastolic area (r=0.347; P=0.003), fractional area change (r=-0.387; P<0.001), and TR grade (r=0.447; P<0.001). At follow-up, 46 (65.7%) had mild or less TR (group A) and 24 (34.3%) had moderate or greater TR (group B). Prestage 1 3DE showed greater TV tethering volume and flatter annulus in group B. Survival was better in group A. CONCLUSIONS: Increased TV tethering volume and flatter bending angle prestage 1 palliation is associated with TV failure at medium-term follow-up. Increased prestage 1 tethering is related to having larger TV annulus, larger leaflet area, larger right ventricular size, and reduced systolic function. TR progression results in increased TV intervention and decreased survival.

Which cardiovascular magnetic resonance planes and sequences provide accurate measurements of branch pulmonary artery size in children with right ventricular outflow tract obstruction?

Children with right ventricular outflow tract obstructive (RVOTO) lesions require precise quantification of pulmonary artery (PA) size for proper management of branch PA stenosis. We aimed to determine which cardiovascular magnetic resonance (CMR) sequences and planes correlated best with cardiac catheterization and surgical measurements of branch PA size. Fifty-five children with RVOTO lesions and biventricular circulation underwent CMR prior to; either cardiac catheterization (n = 30) or surgery (n = 25) within a 6 month time frame. CMR sequences included axial black blood, axial, coronal oblique and sagittal oblique cine balanced steady-state free precession (bSSFP), and contrast-enhanced magnetic resonance angiography (MRA) with multiplanar reformatting in axial, coronal oblique, sagittal oblique, and cross-sectional planes. Maximal branch PA and stenosis (if present) diameter were measured. Comparisons of PA size on CMR were made to reference methods: (1) catheterization measurements performed in the anteroposterior plane at maximal expansion, and (2) surgical measurement obtained from a maximal diameter sound which could pass through the lumen. The mean differences (Δ) and intra class correlation (ICC) were used to determine agreement between different modalities. CMR branch PA measurements were compared to the corresponding cardiac catheterization measurements in 30 children (7.6 ± 5.6 years). Reformatted MRA showed better agreement for branch PA measurement (ICC > 0.8) than black blood (ICC 0.4-0.6) and cine sequences (ICC 0.6-0.8). Coronal oblique MRA and maximal cross sectional MRA provided the best correlation of right PA (RPA) size with ICC of 0.9 (Δ -0.1 ± 2.1 mm and Δ 0.5 ± 2.1 mm). Maximal cross sectional MRA and sagittal oblique MRA provided the best correlate of left PA (LPA) size (Δ 0.1 ± 2.4 and Δ -0.7 ± 2.4 mm). For stenoses, the best correlations were from coronal oblique MRA of right pulmonary artery (RPA) (Δ -0.2 ± 0.8 mm, ICC 0.9) and sagittal oblique MRA of left pulmonary artery (LPA) (Δ 0.2 ± 1.1 mm, ICC 0.9). CMR PA measurements were compared to surgical measurements in 25 children (5.4 ± 4.8 years). All MRI sequences demonstrated good agreement (ICC > 0.8) with the best (ICC 0.9) from axial cine bSSFP for both RPA and LPA. Maximal cross sectional and angulated oblique reformatted MRA provide the best correlation to catheterization for measurement of branch PA's and stenosis diameter. This is likely due to similar angiographic methods based on reformatting techniques that transect the central axis of the arteries. Axial cine bSSFP CMR was the best surgically measured correlate of PA branch size due to this being a measure of stretched diameter. Knowledge of these differences provides more precise PA measurements and may aid catheter or surgical interventions for RVOTO lesions.

Anthracycline induced cardiac toxicity in pediatric Ewing sarcoma: a longitudinal study.

BACKGROUND: Reports on incidence and factors associated with anthracycline cardiotoxicity in patients with Ewing sarcoma vary and few studies evaluate effect over time. Longitudinal trends in cardiac function and prognostic value of % decline in ejection fraction (EF) during therapy have not been previously described in Ewing sarcoma. PROCEDURE: A retrospective review of patients age <17 years, diagnosed with Ewing sarcoma during 1978-2006, treated at British Columbia Children's Hospital with anthracycline chemotherapy was undertaken. Echocardiograms performed pre-treatment, worst function during treatment, on therapy completion; worst function during surveillance and the most recent echocardiogram were reviewed. Cardiac toxicity was graded using Common Terminology Criteria for Adverse Events v 3.0 and 4.0. RESULTS: Among 71 eligible patients, median age at diagnosis 11.1 years, median cumulative dose of anthracycline was 365 mg/m2 . There were 397 echocardiograms with 153 (39%) abnormal. There were 21/71 patients with EF < 50%, 11 with EF < 40% and five cardiac deaths including 2/3 patients post-cardiac transplant. The median time to worst cardiac function was 51 months. Post-therapy completion 16/71 patients with progressive decline in cardiac function were noted. No patient with 10-15% decline in EF during therapy developed cardiotoxicity. Younger age (P = 0.004) and low BMI (P = 0.034) as continuous variables with anthracycline administration by IV push (P = 0.03) were risk factors for cardiotoxicity on univariate analysis but not significant within logistic regression models. CONCLUSIONS: The high incidence of cardiotoxicity associated with higher administered anthracycline dose, young age, bolus infusion, and EF decline warrants evaluation in a larger cohort.

Postoperative fever and major infections after pediatric cardiac surgery.

OBJECTIVE: 1) to identify the current status of major infections and other etiologies of postoperative fever from pediatric cardiac surgery 2) to determine the risk factors of major infections. MATERIAL AND METHOD: Databases of pediatric cardiac surgery patients in 2005 were retrospectively reviewed. The main outcomes of interest were postoperative fever and its etiologies. Potential predictors were analyzed by comparing patients who developed or did not have infections. RESULTS: Two hundred thirty patients, 43% (n = 99) developed postoperative fever. Major infections occurred in 13.5% (n = 31), and postpericardiotomy syndrome (PPS) was seen in 8.7% (n = 20) of the patients. The infection rate was 16.9/100 procedures, including pneumonia (29 episodes) and bloodstream infection (6 episodes). Risk factors were infancy, prolonged ventilator support > 2 days, hospital length of stay (LOS) > 14 days, intensive care unit (ICU) LOS > 3 days, re-open procedure, and extubation failure rate. Conversely, cyanosis and high complexity operations were not associated. Positive erythrocyte sedimentation rate was related to infections or to PPS (the area under the ROC = 0.72). CONCLUSION: Following pediatric cardiac surgery major infections are still problematic. The risks increase with infancy, prolonged ventilator support, prolonged hospital and ICU LOS, re-open procedure, and extubation failure.

Surveillance of pediatric cardiac surgical outcome using risk stratifications at a tertiary care center in Thailand.

Objectives. To determine in-hospital mortality and complications of cardiac surgery in pediatric patients and identify predictors of hospital mortality. Methods. Records of pediatric patients who had undergone cardiac surgery in 2005 were reviewed retrospectively. The risk adjustment for congenital heart surgery (RACHS-1) method, the Aristotle basic complexity score (ABC score), and the Society of Thoracic Surgeons and the European Association for Cardiothoracic Surgery Mortality score (STS-EACTS score) were used as measures. Potential predictors were analyzed by risk analysis. Results. 230 pediatric patients had undergone congenital cardiac surgery. Overall, the mortality discharge was 6.1%. From the ROC curve of the RACHS-1, the ABC level, and the STS-EACTS categories, the validities were determined to be 0.78, 0.74, and 0.67, respectively. Mortality risks were found at the high complexity levels of the three tools, bypass time >85 min, and cross clamp time >60 min. Common morbidities were postoperative pyrexia, bleeding, and pleural effusion. Conclusions. Overall mortality and morbidities were 6.1%. The RACHS-1 method, ABC score, and STS-EACTS score were helpful for risk stratification.

The results of transcatheter closure of VSD using Amplatzer® device and Nit Occlud® Lê coil.

OBJECTIVE: We retrospectively reviewed the result of patients who underwent transcatheter closure of ventricular septal defect (VSD) using Amplatzer® Perimembranous or Amplatzer® muscular VSD device (the Amplatzer® group) and Nit Occlud® Lê VSD Coil (the Pfm group). BACKGROUND: Perimembranous type (PmVSD) and doubly committed subarterial (DCSA) VSD were the major isolated congenital heart defects in Thai children. Transcatheter device closure technique for both types of VSD has emerged as an alternative treatment to surgery. METHODS: Retrospectively, data was reviewed between 2003 and 2009. RESULTS: 116 patients were enrolled. Device or coil was successfully implanted in 94%. Complete closure at 24 hr is slightly higher in the Amplatzer® group. The average size of VSD in the Amplatzer® group was larger than the Pfm group (P = 0.001). The Pfm coil was primarily deployed in DCSA VSD when compared with the Amplatzer® group (P < 0.01). At 6 months follow-up the residual shunt was comparable (P = 0.054). There was only one transient AV block (AVB) in the Pfm group and 5 AVB in the Amplatzer® group. Four pacemakers were placed in the Amplatzer® group. CONCLUSIONS: Transcatheter closure of VSD in both Pm VSD and DCSA can be achieved by using either of the device. The Amplatzer® VSD device had the advantage of closure of larger defects with immediate less residual shunt but appeared to have a significant number of 3° AVB, which required pacemaker implantation. The Nit Occlud® Lê VSD Coil had the advantage of closure of both types of defects, in particular DCSA VSD with only small residual shunt.