Effect of Atrial Septostomy on Left Ventricular Function in Pediatric Dilated Cardiomyopathy Requiring ECMO.

Balloon atrial septostomy (BAS) reduces left ventricular (LV) hypertension during extracorporeal membrane oxygenation (ECMO). However, the acute effect of BAS on LV function as measured by echocardiography is unknown. This was a Retrospective analysis of clinical outcome, LV dimensions, and LV function in dilated cardiomyopathy patients 0-18 years old who underwent BAS on ECMO. In 13 patients with median (IQR) age of 2.3 (0.6-10.9) years, there were no differences in clinical markers of cardiac output at intervals between 12 h before and 6 days after BAS. In addition, BAS was associated with a low rate of periprocedural complications (0.0%), acute kidney injury (7.7%), and worsening radiographic pulmonary vascular congestion (30.7%). There was a significant worsening in LV end systolic diameter (LVIDs; 3.6 [2.9-4.8] cm vs 4.2 [3.2-5.6] cm vs 3.3 [2.6-4.6] cm, p = 0.025), LV end systolic posterior wall thickness (LVPWs; 0.7 [0.5-0.9] cm vs 0.6 [0.5-0.9] cm vs 0.8 [0.6-1.2] cm, p = 0.038), fractional shortening (FS; 17.6% [8.4-20.4%] vs 6.3% [2.0-9.9%] vs 13.2% [3.6-23.4%], p = 0.013), and ejection fraction (EF; 13.1% [8.7-18.9%] vs 5.3% [2.5-11.1%] vs 9.2% [6.0-16.3%], p = 0.039) following BAS that improved in approximately 1 week. There were no differences in LV global longitudinal strain following BAS. We conclude that BAS was associated with low procedural and clinical adverse event rates in our cohort. The worsening LVIDs, LVPWs, FS, and EF seen immediately after the procedure suggests that BAS causes altered loading conditions affecting LV function in pediatric patients with dilated cardiomyopathy requiring ECMO.

Higher left ventricular stroke volume is associated with aortic dilatation in repaired tetralogy of Fallot patients.

Aortic root dilation has been reported commonly after repair of tetralogy of Fallot. However, the rate and risk factors of progression of the dilation are not fully understood. This is a single-centre, retrospective study to assess the rate and factors associated with progressive dilatation of the aortic root in repaired tetralogy of Fallot patients using cardiac MRI. The presence of the significant aortic dilation and the progression of dilation between initial and follow-up cardiac MRI were examined. The study cohort comprised 72 patients with repaired tetralogy of Fallot. The median age at the initial cardiac MRI scan was 19.6 (interquartile range: 14.6-31) years, and the median follow-up interval was 4.3 (2.9-5.7) years. Median dimension of ascending aorta at initial and follow-up cardiac MRI was 27.0 (22.3-31.0) mm and 29.2 (25.0-32.1) mm, respectively. Significant aortic dilation (the percentage predicted ascending aorta ≥150%) was observed in 11 (15.2%) patients at the initial cardiac MRI and 24 (33.3%) at the follow-up cardiac MRI. The significant aortic dilation at follow-up cardiac MRI was associated with increased indexed left ventricular stroke volume (odds ratio 1.062, p = 0.023). Thirteen patients demonstrated the significant progressive dilation of aorta between initial and follow-up cardiac MRI. The progressive dilation was associated with left ventricular ejection fraction at initial cardiac MRI (odds ratio 1.135, p = 0.048). In patients with repaired tetralogy of Fallot, aortic dilation is common and progresses over time. Cardiac MRI is a valuable tool for identifying individuals at risk for progressive aortic dilation.

Left ventricle hypertrophy and re-modeling in children with essential hypertension: does the race matter?

BACKGROUND: This is the first study to report on the impact of race on differences in the prevalence of echocardiographic left ventricular hypertrophy and left ventricular adaptation at the time of diagnosis of essential hypertension in children. METHODS: This cross-sectional, single-centre study included patients aged 3-18 years who had newly diagnosed essential hypertension. Echocardiography was used to assess left ventricular mass index and left ventricular relative wall thickness. An left ventricular mass index > the 95th percentile for age and gender, and an left ventricular relative wall thickness > 0.42, were used to diagnose left ventricular hypertrophy and concentric adaptation. Various echocardiographic parameters were compared between African Americans and Caucasians. RESULTS: The study included 422 patients (289 African Americans and 133 Caucasians) diagnosed with essential hypertension at a median age of 14.6 (interquartile range; 12.1-16.3) years. Eighty-eight patients (20.9%) had left ventricular hypertrophy. There was no statistically significant difference in the prevalence of left ventricular hypertrophy between African Americans and Caucasians (22.5% versus 17.3%, p=0.22). The median left ventricular relative wall thickness was 0.35 (0.29-0.43), and 114 patients (27.0%) had an left ventricular relative wall thickness > 0.42. The presence of an left ventricular relative wall thickness > 0.42 was significantly higher among African Americans compared to Caucasians (30.1% versus 20.3%, p = 0.04). The African American race was a strong predictor for an left ventricular relative wall thickness > 0.42 (odds ratio 1.7, p = 0.04), but not for left ventricular mass index > the 95th percentile (p = 0.22). Overweight/obesity was a strong predictor for an left ventricular mass index > the 95th percentile. CONCLUSIONS: There was no difference in the prevalence of left ventricular hypertrophy in children with essential hypertension of different races. Obesity, rather than being African American, is associated with left ventricular hypertrophy.

Comparative Effectiveness of Surgical Ligation and Catheter Closure of Patent Ductus Arteriosus in Preterm Infants.

To evaluate the association, if any, between closure modality (surgical ligation SL vs. catheter CC) of a hemodynamically significant patent ductus arteriosus (PDA), after failure of or contraindication to medical therapy, and immediate procedural complications, and post-procedure physiologic status in preterm (gestational age < 32 weeks) infants. In this single-center retrospective cohort study, data were accessed on infants < 32 weeks gestation, who underwent SL or CC of PDA, born from 2019-2021. The choice of modality was determined by parents, after they were provided information on both procedures. Our cohort (n = 112) included 36 (32.1%) infants who underwent SL while 76 (67.9%) underwent CC. The SL group of infants were significantly more immature at birth, younger on admission to the level IV NICU and received more mean (SD) surfactant doses than the CC group. Higher proportions of infants in the SL group had 5-min Apgar scores ≤ 5, seizures, severe intracranial hemorrhage and had received medical therapy for PDA. Both procedures were highly efficacious, with 1 unsuccessful device placement attempt and had low associated adverse events. Two (2.6%) infants had device migration 24 h after CC. SL was associated with a higher rate of immediate postoperative hypothermia whereas, in the CC group, mean airway pressure was significantly lower 48 h after, compared to before the procedure. SL and CC are comparable in short-term efficacy and safety for PDA closure. Long-term outcomes data are needed following both procedures.

Exercise Capacity in Patients with Pulmonary Atresia with Intact Ventricular Septum: Does the Type of Surgical Repair Matter?

Two standard surgical palliative options for neonates born with pulmonary atresia and intact ventricular septum (PA/IVS) include uni-or biventricular repair. Whenever feasible, the biventricular repair is considered to have better exercise capacity (XC) and outcomes. However, there is a paucity of data comparing objective XC between these two surgical techniques. Our aim was to compare XC, including longitudinal changes in patients with PA/IVS following uni-biventricular repair. We performed a single-center retrospective study of survivors with repaired PA/IVS who underwent comprehensive treadmill cardiopulmonary exercise testing. Initial and latest exercise parameters were compared for longitudinal analysis. Demographic and exercise parameters were collated. Peak oxygen uptake (VO2 in ml/kg/min), an indicator of maximal aerobic capacity, peak heart rate, and other measures of spirometry performed at the same time were collected. Recorded parameters included, (a) Percentage of predicted VO2 (% VO2) normalized for age, weight, height, and gender, (b) % oxygen (O2) pulse, (c) anaerobic threshold (AT), (d) Chronotropic index (CI), (e) % Breathing reserve, (f) Forced vital capacity (FVC), (g) % Forced Expiratory volume in 1 s (FEV1), (h) Maximum voluntary ventilation (MVV), and (i) VE/VCO2. Appropriate statistical tests were performed, and a p value < 0.05 was considered significant. A total of 35 patients (43% male, 57% univentricular repair) were included, with a mean (SD) age of 20.1(7.5) years. Patients with univentricular palliation demonstrated significantly impaired peak heart rate, chronotropic index (0.50 ± 0.2 vs. 0.90 ± 0.1, p = 0.02), VE/VCO2 (35.4 ± 5.0 vs. 30.2 ± 2.8, p = 0.001), and %FVC (78.3 ± 8.3 vs. 88.6 ± 15.1, p = 0.02). There was a trend towards reduction in % VO2 in the Fontan patients though it was statistically similar between the groups (68.4 ± 21.4 vs. 81.2 ± 18.9, p = 0.07). Longitudinal data were available for 11 patients in each group, and there was no longitudinal decline in their exercise parameters over similar intermediate follow-up duration [6.8 (UV) vs. 5.3 (BV) years]. We conclude that young survivors with PA/IVS with prior univentricular palliation demonstrated an objective impairment in their chronotropic parameters compared with the biventricular repair. However, this did not translate into a significant difference in their exercise capacity. There was no longitudinal decline in exercise capacity or other parameters over intermediate follow-up.

Ventricular Functional Analysis in Congenital Complete Heart Block Using Speckle Tracking: Left Ventricular Epicardial Compared to Right Ventricular Septal Pacing.

BACKGROUND: Chronic right ventricular (RV) apical pacing in patients with congenital complete atrioventricular block (CCAVB) is associated with left ventricle (LV) dyssynchrony and dysfunction. Hence, alternative pacing sites are advocated. The aim of this study was to compare LV function using STE in selected patients with LV epicardial pacing (LVEp) vs. RV transvenous pacing (RVSp). METHODS: This was a single-center, retrospective study in patients with CCAVB who underwent permanent pacemaker implant at age ≤ 18 years. Age- and gender-matched patients with a normal heart anatomy and function served as the control group. LV function was comprehensively assessed by conventional 2D Echocardiography and speckle-tracking echocardiography (STE). RESULTS: We included 24 patients in the pacemaker group [27.6% male, mean age of 17.1 at last follow-up, follow-up duration of 8.7 years, RVSp (n = 9; 62.5%)] compared to 48 matched healthy controls. Shortening fraction (SF) and ejection fraction (EF) were normal and similar between cases and controls. However, STE detected abnormal LV function in the pacemaker group compared to controls. The former demonstrated lower/abnormal, Peak Longitudinal Strain myocardial (PLS Myo) [- 12.0 ± 3.3 vs. - 18.1 ± 1.9, p < 0.001] and Peak Longitudinal Strain endocardial (PLS endo) [- 16.1 ± 4.1 vs. 1.7 ± 1.7, p < 0.001]. STE parameters of LV function were significantly more abnormal in LVEp vs. RVSp subgroup as demonstrated by lower values for PLS Myo (- 10.1 ± 3.2 vs. - 13.1 ± 2.9, p = 0.03) and PLS Endo (- 13.8 ± 4.4 vs. - 17.5 ± 3.3, p = 0.03). CONCLUSION: STE was more sensitive in detecting subtle differences in LV function relative to standard conventional 2D echocardiography (SF and EF) in selected patients with CCAVB and a permanent pacemaker. Furthermore, STE demonstrated that transvenous RV septal pacing was associated with better LV systolic function preservation than LV epicardial pacing for comparable post-implant intervals.

Late health outcomes after dexrazoxane treatment: A report from the Children's Oncology Group.

BACKGROUND: The objective of this study was to examine long-term outcomes among children newly diagnosed with cancer who were treated in dexrazoxane-containing clinical trials. METHODS: P9404 (acute lymphoblastic leukemia/lymphoma [ALL]), P9425 and P9426 (Hodgkin lymphoma), P9754 (osteosarcoma), and Dana-Farber Cancer Institute 95-01 (ALL) enrolled 1308 patients between 1996 and 2001: 1066 were randomized (1:1) to doxorubicin with or without dexrazoxane, and 242 (from P9754) were nonrandomly assigned to receive dexrazoxane. Trial data were linked with the National Death Index, the Organ Procurement and Transplantation Network, the Pediatric Health Information System (PHIS), and Medicaid. Osteosarcoma survivors from the Childhood Cancer Survivor Study (CCSS; n = 495; no dexrazoxane) served as comparators in subanalyses. Follow-up events were assessed with cumulative incidence, Cox regression, and Fine-Gray methods. RESULTS: In randomized trials (cumulative prescribed doxorubicin dose, 100-360 mg/m2 ; median follow-up, 18.6 years), dexrazoxane was not associated with relapse (hazard ratio [HR], 0.84; 95% confidence interval [CI], 0.63-1.13), second cancers (HR, 1.19; 95% CI, 0.62-2.30), all-cause mortality (HR, 1.07; 95% CI, 0.78-1.47), or cardiovascular mortality (HR, 1.45; 95% CI, 0.41-5.16). Among P9754 patients (all exposed to dexrazoxane; cumulative doxorubicin, 450-600 mg/m2 ; median follow-up, 16.6-18.4 years), no cardiovascular deaths or heart transplantation occurred. The 20-year heart transplantation rate among CCSS osteosarcoma survivors (mean doxorubicin, 377 ± 145 mg/m2 ) was 1.6% (vs 0% in P9754; P = .13). Among randomized patients, serious cardiovascular outcomes (cardiomyopathy, ischemic heart disease, and stroke) ascertained by PHIS/Medicaid occurred less commonly with dexrazoxane (5.6%) than without it (17.6%; P = .02), although cardiomyopathy rates alone did not differ (4.4% vs 8.1%; P = .35). CONCLUSIONS: Dexrazoxane did not appear to adversely affect long-term mortality, event-free survival, or second cancer risk.

Device-detected nonsustained ventricular tachycardia in adult congenital heart disease without tetralogy of fallot.

OBJECTIVES: To evaluate any association between non-sustained ventricular tachycardia (NSVT) detected by intra-cardiac device and clinical outcomes in repaired adult congenital heart disease (ACHD) without tetralogy of Fallot (TOF). BACKGROUND: NSVT portends a higher risk of serious ventricular tachyarrhythmia in TOF. However its clinical significance when incidentally detected by implantable cardiac device is not well elucidated in non-TOF ACHD cohort. METHODS: We performed a single center, retrospective, longitudinal follow-up study in repaired ACHD (≥18 years) patients without TOF who hosted a pacemaker or automatic implantable cardiac defibrillator (AICD). The cohort was divided based on presence/absence of device detected NSVT. The primary end-point was a composite of sustained ventricular tachycardia (VT), ventricular fibrillation (VF), or sudden cardiac death (SCD). RESULTS: One hundred fifty eight patients (male 56.3%, median [IQR] age of 35 [28-43] years at last follow-up] with longitudinal post-implant follow-up duration of 8 (5-12) years were included. NSVT was detected in 52 (33%) patients. The primary composite end-point was more frequent in NSVT group [11.5% vs. 2.8%; p = .04]. Patients with NSVT were (i) older at the time of initial implant (age 25 vs. 18 years, p = .011) and more frequently demonstrated (ii) systemic ventricular dysfunction (44% vs. 26%; p = .015), as well as (iii) history of ventriculotomy (38% vs. 21%; p = .017). CONCLUSIONS: In our repaired ACHD cohort, we noted a significant association between device-detected-NSVT and the primary composite end-point of sustained VT/VF or SCD. Systemic ventricular dysfunction and history of ventriculotomy were more frequent in the NSVT group and likely constituted the clinical milieu.

Anthracycline Treatment and Left Atrial Function in Children: A Real-Time 3-Dimensional Echocardiographic Study.

Anthracycline (AC) therapy is associated with left ventricular (LV) dysfunction. Left atrial (LA) size and function are used to assess LV diastolic function in heart failure in adults. Data on LA size and function following AC therapy in children is limited. We hypothesized that LA size and function will be abnormal in children following AC chemotherapy. This retrospective review included patients who received AC for pediatric cancers. Controls had normal echocardiograms performed for evaluation of chest pain, murmur, or syncope. Real-time three-dimensional echocardiography was performed to evaluate LA reservoir, conduit, and booster pump function parameters. In addition to LA volume data, LV shortening fraction, spectral and tissue Doppler variables assessing diastolic function as well as myocardial performance index was obtained. Groups with and without AC therapy were compared by student t-test and chi-square test. We evaluated 136 patients, 55 (40.4%) had received AC. There was no significant difference between the groups in LV shortening fraction, diastolic as well as global function indices. LA reservoir and conduit function parameters were significantly lower in AC group compared to controls. The booster function parameters showed variable results. It is intriguing that AC-treated children have smaller LA reservoir and abnormal booster function. We speculate that these findings may reflect early changes in LA compliance associated with AC exposure. Assessment of LA volumes and function as prognostic markers of AC-induced cardiotoxicity in children is warranted.

Exercise Capacity After Arterial Switch Operation in Patients with D-Transposition of Great Arteries: Does the Coronary Artery Anatomy Matter?

Variant coronary anatomy (VarCA) is frequent in D-Transposition of the great arteries (d-TGA). There are a paucity of data on the effect of the VarCA on the exercise capacity (XC) in patients with repaired d-TGA. This retrospective study included patients with d-TGA who underwent an arterial switch operation (ASO) and had at least one cardiopulmonary exercise test (CPET). Data from the treadmill CPET and simultaneously performed spirometry were collected. The parameters of CPET were compared between patients with usual anatomy vs. VarCA. Longitudinal changes in XC in patients with ASO were also analyzed. A total of 44 patients with either usual coronary anatomy (n = 27, 61%) or VarCA (n = 17, 39%) met inclusion criteria. There was no significant difference in oxygen consumption (%VO2) at initial CPET (104 vs. 100%, p = 0.53) between the two groups. Abnormal %VO2 (< 85%) was uncommon in both groups (n = 2, 7.4% vs. n = 4; 23.5%; p = ns). For longitudinal changes, there was no significant decline in %VO2 in either group: (i) usual coronary anatomy (n = 15, median follow-up 4.8 years, %VO2 111 vs. 108%; p = 0.306) and (ii) VarCA (n = 10, median follow-up 6.6 years, %VO2 106 vs. 92%; p = 0.441). Spirometry was abnormal in 25 (59.5%) patients [restrictive (n = 8, 19.0%), obstructive (n = 15, 35.7%), and mixed (n = 2, 4.8%)] butabnormal spirometry had no impact on the XC. Patients with d-TGA who underwent neonatal ASO uniformly exhibited good XC without any longitudinal decline on medium-term follow-up, regardless of coronary artery anatomy. Although frequent (60%), abnormal spirometry was not associated with reduced exercise capacity.

Assessing Non-invasive Studies to Evaluate Resynchronization Pacing Effectiveness in the Young.

Appropriate non-invasive assessments (ECHO/ECG) of cardiac resynchronization pacing therapy (CRT) among younger patients (pts) with/without (w/wo) congenital heart disease (CHD) are not established. Ejection fraction (EF) and QRS can be unreliable due to anatomy, surgical repairs, and pre-existing pacemakers (PM). This study correlates updated non-invasive studies, including newer strain values, with clinical and invasive hemodynamic assessments of CRT response in the young. Sixteen pts (mean age 18.5 ± 6 years, 10/16 with pre-existing pacemakers) underwent CRT for heart failure (NYHA II-III). CHD included septal defects and Tetralogy of Fallot. Assessment of CRT efficacy was based on clinical findings, direct catheterization studies [pressures, contractility indices (dP/dt-max)], ECG changes, and ECHO studies [including updated global (GLS), left atrial strain (LAS), and sphericity indices] pre- and at 1-month and 1-year post-CRT. After 1 year following CRT, all pts improved (II-III to I-II) in clinical NYHA status. Contractility (dP/dt) increased (932 ± 351 vs 561 ± 178.7 mmHg-sec [p = 0.001]). QRS duration shortened only among pts with pre-existing PM (160 ± 25 vs 134 ± 25 ms [p = 0.02]). Standard ECHO parameters, including chamber dimensions and EF, showed no appreciable changes from pre-CRT values. However, endocardial GLS [(- 6.4 vs. - 9.6%) p = 0.0003] and LAS [(- 5.8 vs - 9.3%) p = 0.02] values significantly improved. Although CRT is applicable to younger pts, accurate non-invasive evaluations of response are lacking. This study establishes that newer strain values better correlate with clinical and hemodynamic changes over other parameters and offer more appropriate assessments of CRT response.

Longitudinal Trends in Body Mass Index for Adults with Congenital Heart Disease.

Obesity is a modifiable, independent risk factor for adverse long-term outcomes in children and adults. Our objective was to determine the prevalence of overweight and obese status in a cohort of adults with congenital heart disease (CHD) as well as to assess longitudinal trends over a 20-year period. The study group consisted of patients 18 years of age and older followed at our adult CHD clinic. Body mass index (BMI) data were collected from our index period, consisting of patient encounters from 2009 to 2012 (Period 2), as well as during 2000-2003 (Period 1) and 2017-2020 (Period 3) when available. The study cohort was subdivided into three groups per published guidelines: simple, moderate, and greater CHD complexity. The prevalence of obesity and overweight status was compared among the different groups as well as with published data (NHANES). Our cohort in Period 2 consisted of 261 subjects. The median age (25-75% interquartile range) for Period 2 was 27.6 (21.1-35.9) years and BMI was 25.2 (21.7-30.0) kg/m2 with 8.0% underweight, 40.0% with normal weight, 27.0% overweight, and 25% obese. 95 patients had follow-up data from each time period, with 96% of patients having moderate or greater complexity of CHD. The combined percentage of overweight and obese patients for the moderate and greater complex CHD groups increased from 42 and 37% in period 1 to 60% and 65% in period 3, respectively. The percentage of obese patients with moderate and greater CHD complexity increased by 250% and 55%, respectively, from Period 1 to 3. Our study cohort had a high prevalence of overweight and obese weight status. Given adults with CHD have high baseline cardiovascular morbidity, the presence of obesity can increase their risk for poor outcomes, highlighting the need for prevention of this modifiable risk factor.

An echocardiographic finding mimicking tricuspid atresia in a neonate with dilated cardiomyopathy.

We report a neonate with dilated cardiomyopathy and have echocardiographic findings consistent with "functional" tricuspid atresia. There was an echo-bright, plate-like tissue at the tricuspid valve position with no forward flow across it. This report underscores the role of right ventricle intracavitary haemodynamic influence on the tricuspid valve leaflet excursion and demonstrates a phenomenon of "pseudo or functional tricuspid atresia" mimicking tricuspid atresia in a patient with acute presentation of cardiomyopathy.

Haemodynamic impact of chest compressions in the delivery room.

Among 65 neonates with encephalopathy undergoing cooling, 30 (46.1%) received chest compressions during delivery room resuscitation. Despite differences in encephalopathy severity, early (<24 hours) biventricular function on echocardiogram (fractional area change, myocardial performance indices, systolic to diastolic duration ratios, tricuspid annular plane systolic excursion) was comparable between groups with and without chest compressions. Epinephrine receipt was associated with abnormal tricuspid annular plane systolic excursion.

Pneumocystis pneumonia with hypogammaglobulinemia in a pediatric patient who underwent heart transplantation.

A 23-month-old Caucasian female who had heart transplantation (HT) at 11 days of age was diagnosed with Pneumocystis pneumonia (PCP) in the setting of secondary hypogammaglobulinemia (HGG). She was diagnosed with HGG at 5 months of age and had been receiving monthly intravenous immunoglobulin infusion. This is the first case report describing the clinical course of PCP in a pediatric patient with HGG. She developed PCP 23 months after HT even when she was off steroids and was receiving timely IVIG. The case posed some clinical questions regarding PCP prophylaxis and HGG management.

Crohn's disease with dilated cardiomyopathy in a child: An experience with heart transplantation.

BACKGROUND: DCM has rarely been reported in children with CD, but is a recognized complication in adults. DCM with uncontrolled heart failure may need heart transplantation, which could be challenging in CD. CASE DESCRIPTION: We present a 9-year-old female with CD who was diagnosed with DCM and a measured Ejection fraction ~25.8%. She was initiated on heart failure treatment, but continued to have progressive symptoms and underwent bicaval OHT three months after her initial presentation. Her post-operative course was complicated by perforation of the rectosigmoid junction requiring exploratory laparotomy and primary repair of the perforation. This was believed to be secondary to her underlying CD and possibly reperfusion injury after heart transplant. During the first-year post heart transplant, she had 4 episodes of acute cellular rejection. These episodes were treated with high dose steroids with good results. The patient has been in remission from CD since transplantation. For the last two years she is doing well, with no further rejection episodes on current immunosuppression. CONCLUSION: DCM, though rare, can occur in patients with CD, whether active or in remission. The development of DCM could be insidious and keeping a high index of suspicion is important and subtle signs suggestive of cardiac involvement should warrant further investigation. The post-transplant management can be challenging with early morbidity in the first post-transplant year but overall good median survival and quality of life for our patient to date.

Left posterior fascicular ventricular tachycardia in a young infant with a structurally normal heart: Clinical course and caveats to electrocardiographic diagnosis.

In this illustrative case report, we describe a rare case of left posterior fascicular ventricular tachycardia (LPFVT) in a 2 month-old infant with emphasis on electrocardiographic caveats to diagnosis. The clinical course, treatment, and eventual resolution of the VT over a 2 year follow-up is comprehensively compared and contrasted to a modicum of individual such case reports of infants. The corpus of each such case of infantile LPVT is systematically reviewed and succinctly summarized in a tabular compendium. The collective knowledge compiled here should allow for a refined approach to diagnosis and management of this unusual arrhythmia.

Does Premature Ventricular Contractions Affect Exercise Capacity in Teenagers with Normal Hearts?

Premature ventricular contractions (PVCs) are common in teenagers even in the absence of structural heart disease or channelopathy. The suppression of PVCs with exercise is a favorable prognostic indicator. There is a paucity of data regarding the relationship between exercise capacity and PVC burden in this population. Our objective was to evaluate the association between various exercise stress parameters and PVC burden ascertained with a 24 h Holter in children without structural heart disease and/or channelopathy. In this retrospective study, 447 patient's charts with a diagnosis of PVC were reviewed at a single tertiary center. The study cohort consisted of ninety one patients with no structural heart disease or channelopathy who underwent an echocardiogram, maximal stress test, and 24 h Holter monitor. The cohort was divided into two groups based on PVC burden by 24-h Holter monitoring: < 10% and ≥ 10%. Peak oxygen uptake (VO2 in ml/kg/min), an indicator of maximal aerobic capacity, was collected. Other exercise parameters included a) percentage of predicted VO2 (%VO2) based on age, weight, height, and gender b) percent oxygen pulse, c) Anaerobic threshold (AT), and d) Metabolic equivalents. Demographic and exercise stress test-derived parameters were compared between the two groups using student t test and a p value < 0.05 was considered significant. In our cohort of 91 patients, the mean (SD) age at exercise was 14.5 (3.2) years with 56 (62%) males. Left ventricle shortening fraction (LVFS) was ≥ 28% in all enrolled patients. PVCs were monomorphic in 72(80%) patients. The mean (SD) PVC burden was 14.43% (12.3) ranging from 0.1 to 49.8%. PVC burden was ≥ 10% in 48 (53%) patients. Eighty eight (97%) patients in the study cohort had suppression of PVCs with exercise. There were no significant differences between the two groups (< 10% vs. ≥ 10% PVC burden) with respect to demographic or exercise test-derived parameters. Univariate regression between PVC burden and %VO2 did not show significant correlation (r = - 0.04, p = 0.75). Children even with ≥ 10% PVC burden did not demonstrate any objective decrease in their exercise capacity. A plausible reason for no difference in exercise capacity in our cohort may be due to lower PVC load or shorter duration of PVCs compared to adults.

The Identification and Impact of Abnormal Spirometry Patterns on Exercise Capacity in Pediatric Patients with Fontan Palliation.

Reduced exercise capacity and restrictive lung physiology are common in patients after Fontan palliation (FP). However, there is paucity of data regarding the association between specific spirometry patterns and key exercise parameters in this population. This is a single-center, cross-sectional, study correlating pulmonary function and exercise parameters in children with FP. Patients who were ≤ 18 years of age and underwent a comprehensive cardiopulmonary treadmill exercise stress test (CPT) and spirometry at the same time, were included. Patients were categorized as (i) normal or (ii) abnormal based on the results of spirometry. The abnormal group was subdivided into (a) restrictive, (b) obstructive, and (c) mixed patterns. Demographic and key exercise parameters were compared between groups. Our study included 82 patients who underwent CPT at 13.6 (IQR, 11.3-15.4) years of age. A reduced exercise capacity (%VO2 ≤ 85%) was noted in the majority (n = 50, 61%). Spirometry was abnormal in 47 (57%) patients [restrictive (n = 25, 30%), obstructive (n = 12, 15%), and mixed (n = 10, 12%)]. The abnormal spirometry group had significant lower %VO2 (77% vs. 92%, p = 0.01) and METS (8.4 vs. 9.6, p = 0.02). Subgroup analysis revealed that obstructive (p = 0.04) and mixed (p = 0.02) patterns were associated with a significant decrease in % VO2. Majority of the children demonstrated an abnormal spirometry pattern post-FP. Abnormal pulmonary function was associated with the reduced exercise capacity. Identification and treatment of the abnormal lung function may improve the exercise capacity in these patients and improve the morbidity.

Inferior Vena Cava Collapsibility Index to Assess Central Venous Pressure in Perioperative Period Following Cardiac Surgery in Children.

The inferior vena cava collapsibility index (IVCCI) is an ultrasound method used to assess central venous pressure (CVP). Our objective was to evaluate the correlation between IVCCI and CVP in children during the early period following surgery for congenital heart disease (CHD). Prospective study performed in a single tertiary care center. Patients ≤ 18 years old, who underwent cardiopulmonary bypass surgery for CHD, were enrolled. Ultrasound images of the inferior vena cava (IVC) were obtained at two time points; the first was within 2 h of arrival to the CICU and the second was 12-18 h from the first measurement. CVP measured by catheter placed during surgery was recorded within minutes of performing ultrasound. Maximum and minimum IVC diameters were measured by 2D images and M mode method. Seventy patients (47.1% males), with median age 7 months (IQR 4-47 months) and weight 6.9 kg (IQR 4.8-13.5 kg), were evaluated. The 2D IVCCI had inverse correlation with CVP in patients breathing spontaneously; r = - 0.76 (p < 0.01) and r = - 0.73 (p < 0.01), during the first and second measurements, respectively. The 2D IVCCI ≤ 0.24 had sensitivity, specificity, and negative predictive value of 94%, 79%, and 88.9% , respectively, to detect CVP ≥ 10 mmHg. No correlation was found between IVCCI and CVP during positive pressure ventilation. There is a significant inverse correlation between 2D IVCCI and CVP in spontaneously breathing children after surgery for CHD. Use of 2D IVCCI for monitoring CVP could reduce the frequency and duration of CVP catheters and their inherent complications.