Trivial aortic valve regurgitation in children and adolescents with structurally normal hearts: physiologic or pathologic?

BACKGROUND: Trivial regurgitation from a normal aortic valve is rarely seen in healthy children and adolescents. The aim of this study was to evaluate timing of presentation, associated conditions, and medium-term prognosis of this incidental finding. METHODS: Paediatric patients observed to have trivial aortic valve regurgitation with otherwise normal echocardiograms were retrospectively analysed. Clinical and echocardiographic parameters were measured and categorised on presentation and follow-up. RESULTS: Sixty patients (39 males) were identified over a 13-year period. Age at presentation was 14.8 years (IQR 12.9-16.0), height z-score was + 0.71 (95% CI + 0.48- + 0.94), and body mass index z-score was + 0.66 (95% CI + 0.40- + 0.92). Median aortic regurgitation vena contracta diameter was 1.0 mm (IQR 0.8-1.3). Aortic valve strands were visualised in 28% and physiologic mitral regurgitation in 32%. Aortic annulus, sinotubular junction, and mid-ascending aorta diameters were normal, and mean aortic sinus diameter was only slightly increased (z-score + 0.23, 95% CI + 0.02- + 0.44). Follow-up data were obtained in 36 patients from 1 to 6.7 years later (median 2.1). Aortic regurgitation was no longer detectable in 28%, and none exhibited worsening. Mitral regurgitation prevalence was lower in those with aortic regurgitation resolution versus persistence (10% versus 50%, p = 0.03). CONCLUSIONS: Trivial aortic regurgitation in paediatric patients with normal hearts is more common in adolescents and is associated with an increased prevalence of aortic valve strands and physiologic mitral regurgitation. These findings do not worsen during growth and may resolve consistent with being physiologic rather than pathologic.

Right and left ventricular mass development in early infancy: Correlation of electrocardiographic changes with echocardiographic measurements.

BACKGROUND: Right ventricular mass indexed to body surface area (RVMI) decreases and left ventricular mass index (LVMI) increases rapidly and substantially during early infancy. The relationship between these sizeable mass transformations and simultaneous electrocardiographic changes have not been previously delineated. METHODS: Normal term infants (#45 initially enrolled) were prospectively evaluated at 2 days and at 2-week, 2-month, and 4-month clinic visits. Ventricular masses were estimated with 2D echocardiographic methods. QRS voltages were measured in leads V1, V6, I and aVF. RESULTS: Mean QRS axis shifted from 135 (95%CI 124, 146) to 65 degrees (95%CI 49, 81) and correlated with both RVMI decrease and LVMI increase (R = 0.46⁎ vs. 0.25†, respectively. *p < 0.01, †p < 0.05). As RVMI decreased from mean 28.1 (95%CI 27.1, 29.1) to 23.3 g/m2 (95%CI 21.4, 25.2) so did V1R and V6S voltages. RVMI changes correlated with V1R, V6S, and V1R + V6S voltages (R = 0.29*, 0.23† and 0.35*, respectively. *p < 0.01, †p < 0.05) but not with V1R/S ratio. As LVMI increased from 44.6 (95%CI 42.9, 46.3) to 55.4 g/m2 (95%CI 52.3, 58.5) V6R and V6Q increased but V1S voltage did not. LVMI changes correlated with V6R, V6R-S, and V6(Q + R)-S voltages (R = 0.31*, 0.34*, and 0.38* respectively. *p < 0.01) but not with V1S or V6R/S (R = 0.01 and 0.18 respectively, p = NS). CONCLUSIONS: During early infancy the RVMI decrease correlates best with the QRS axis shift and V1R + V6S voltage, and the LVMI increase correlates best with V6R-S and V6(Q + R)-S voltages.

Adenosine sensitive left ventricular summit ventricular tachycardia in a pre-adolescent: case report.

Background: Sustained forms of tachycardia especially from the left ventricular summit are rare. Adenosine sensitive outflow tachycardias, especially from the left ventricular summit, are rarer still. These arrhythmias may be exercise or stress induced as they are facilitated by catecholamines and characteristically terminate with adenosine, vagal manoeuvres, and beta-blockers. The surface 12-lead electrocardiogram can be used to localize the anatomic site of origin before catheter ablation; however, prediction of the precise origin may still be challenging due to the intimate and complex anatomy of the outflow tracts. Case summary: A 12-year-old female presented to an emergency room with frequent runs of wide complex tachycardia that terminated with adenosine but would spontaneously reinitiate. After three additional temporary terminations with adenosine and because of an inability to completely eliminate tachycardia, she was started on an esmolol infusion that resulted in an abrupt termination of tachycardia. At follow-up, she reported breakthrough episodes of tachycardia with exercise, especially associated with beta-blocker non-compliance. The rest of her cardiac testing was normal apart from an anomalous right coronary artery origin from the left coronary sinus. Given the increased frequency of symptomatic palpitations and medication non-compliance, she underwent an electrophysiology study. During the study, a ventricular tachycardia was successfully mapped to an epicardial focus at the left ventricle summit and was successfully ablated. Discussion: The response of this patient's ventricular tachycardia to adenosine suggests a triggered mechanism. To our knowledge, this is the first unambiguous example of left ventricular tachycardia due to cAMP-mediated triggered activity in this age group.

Presentation and Prognosis of Excessive Asymptomatic Atrial Ectopy in Children and Adolescents With Structurally and Functionally Normal Hearts.

Excessive premature atrial complexes (PACs) in pediatric patients with a structurally normal heart are presumed to be benign and self-resolving, but no studies have confirmed this. Adults with excessive PACs, however, are at increased risk for future sustained atrial arrhythmias and cardiovascular morbidity and mortality. Therefore, we sought to evaluate the clinical course of frequent PACs in asymptomatic children. Patients < 21 years old with numerous asymptomatic PACs (>50/24 hours) were retrospectively selected over a 10-year period. Demographics, clinical characteristics, and results of cardiovascular testing were tabulated. Two groups were defined: those with a significant (>20%) reduction in burden of atrial ectopy versus those with an insignificant (<20%) reduction or increase. Of 6,902 patients, 343 patients (5%) met criteria. Initial median age was 8.3 (interquartile range [IQR] 4.1 to 14) years with comparable male:female ratio. Follow-up Holters were performed on 188 patients (54.8%) at a median interval of 2.2 (IQR 1.3 to 3.6) years. Overall, there was a significant decrease in atrial ectopy burden from 4.2% (IQR 1.9 to 6.5) down to 0.5% (IQR 0.01 to 2.3), with 166 patients (88.3%), demonstrating a decrease of over 20%. Five percent had a small increase, and 6% had an insignificant decrease. None developed cardiac symptoms or sustained supraventricular tachydysrhythmia. Male gender, athletic participation, and discontinuation of stimulant medications were the chief predictors for a reduction of PAC burden on follow-up. Atrial triplets at presentation were associated with a 5.4% increase. In conclusion, this study confirms that excessive asymptomatic childhood PACs with structurally normal hearts are rare and short-term to medium-term prognosis is benign.

Cardiac arrest secondary to arrhythmogenic right ventricular cardiomyopathy in an adolescent male.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare, genetically-inherited cardiomyopathy that may be fatal. We present the case of a 17 year old male who presented after a witnessed cardiac arrest with indeterminate echocardiogram and electrocardiogram (ECG) findings for a specific etiology. Genetic testing revealed a mutation in the PKP2 and DSC2 genes, consistent with ARVC. This report outlines the presentation of ARVC as an aborted sudden cardiac death episode in a previously asymptomatic teenager, investigations for ARVC and highlights the importance of adequate cardiopulmonary resuscitation in the overall prognosis. Implantable cardiac defibrillator (ICD) placement for secondary prevention is necessary.

Electrophysiological effects and clinical utility of propafenone in children.

AIM: This retrospective case series study sought to describe the safety and clinical effectiveness of propafenone for the control of arrhythmias in children with and without CHD or cardiomyopathy. METHODS: We reviewed baseline characteristics and subsequent outcomes in a group of 63 children treated with propafenone at 2 sites over a 15-year period Therapy was considered effective if no clinically apparent breakthrough episodes of arrhythmias were noted on the medication. RESULTS: Sixty-three patients (29 males) were initiated on propafenone at a median age of 2.3 years. CHD or cardiomyopathy was noted in 21/63 (33%). There were no significant differences between demographics, clinical backgrounds, antiarrhythmic details, side effect profiles, and outcomes between children with normal hearts and children with CHD or cardiomyopathy. Cardiac depression at the initiation of propafenone was more common amongst children with CHD or cardiomyopathy compared to children with normal hearts. Systemic ventricular function was diminished in 15/63 patients (24%) prior to starting propafenone and improved in 8/15 (53%) of patients once better rhythm control was achieved. Other than one child in whom medication was stopped due to gastroesophageal reflux, no other child experienced significant systemic or cardiac side effects during treatment with propafenone. Propafenone achieved nearly equal success in controlling arrhythmias in both children with normal hearts and children with congenital heart disease or cardiomyopathy (90% versus 86%, p = 0.88). CONCLUSION: Propafenone is a safe and effective antiarrhythmic medication in children.

Prominent prolapsing Chiari network: presentation and prognosis in paediatric patients.

Chiari network is an infrequently visualized web-like structure in the right atrium that is usually thin and small. Rarely, it can be prominent and elongated with protrusion into the right ventricle during diastole and complications have been reported. Thirty-eight patients (median age 2.5 years) with prolapsing Chiari network were identified and associated cardiac abnormalities documented. Echocardiographic right and left heart parameters were measured and compared to normative data. At presentation, the extent of Chiari network prolapse below the tricuspid annulus was 9.1 ± 3.5 mm (mean ± standard deviation), mean pulmonary valve annulus diameter z-value was reduced (-0.91 ± 0.64), and mean aortic valve z-value was enlarged (+0.97 ± 0.87). Fourteen patients exhibited no other cardiac abnormality. Eight were noted to have atrial septal defects, eight demonstrated supraventricular dysrhythmias, six had mild to moderate tricuspid valve regurgitation, and one patient each had an atrial septal aneurysm, severe pulmonic valve stenosis, small perimembranous ventricular septal defect, bicuspid aortic valve, and mild right upper pulmonary vein stenosis. Fourteen patients (37%) were seen in follow-up from 1 to 8.5 years later (median 3.2 years). During that time, the magnitude of prolapse across the tricuspid valve decreased by up to 7 mm (median 2 mm). Interventions were required in three patients, but many associated cardiac abnormalities resolved spontaneously with growth. Thus, the presence of a prolapsing Chiari network has a substantial risk of associated CHDs. However, the extent of Chiari network prolapse gradually decreases and many related abnormalities resolve during growth.

Epicardial Ablation of Persistent Junctional Reciprocating Tachycardia in an Infant With Tachycardia-Induced Cardiomyopathy.

A 3-month-old infant who developed persistent junctional reciprocating tachycardia (PJRT)-induced cardiomyopathy that was successfully treated with radiofrequency ablation. To our knowledge this is the youngest reported patient with a successful epicardial lesion placed in a diverticulum off the coronary sinus and also the first report of a PJRT connection located at an epicardial site distinct from the mitral and tricuspid valve annulus. We use this case to highlight how low-power lesions in the coronary sinus in the youngest of patients can achieve results safely. (Level of Difficulty: Advanced.).

COVID-19 and Gender Disparities in Pediatric Cardiologists with Dependent Care Responsibilities.

The COVID-19 pandemic disproportionately affects females in the home and workplace. This study aimed to acquire information regarding the gender-specific effects of the COVID-19 lockdown on aspects of professional and personal lives of a subset of pediatric cardiologists. We sent an online multiple-choice survey to a listserv of Pediatric Cardiologists. Data collected included demographics, dependent care details, work hours, leave from work, salary cut, childcare hours before and after the COVID-19 peak lockdown/stay at home mandate and partner involvement. Two hundred forty-two pediatric cardiologists with dependent care responsibilities responded (response rate of 20.2%). A significantly higher proportion of females reported a salary cut (29.1% of females vs 17.6% of males, p = 0.04) and scaled back or discontinued work (14% vs 5.3%; p = 0.03). Prior to the COVID-19 lockdown phase, females provided more hours of dependent care. Females also reported a significantly greater increase in childcare hours overall per week (45 hours post/30 hours pre vs 30 hours post/20 hours pre for men; p < 0.001).  Male cardiologists were much more likely to have partners who reduced work hours (67% vs 28%; p < 0.001) and reported that their partners took a salary cut compared with partners of female cardiologists (51% vs 22%; p < 0.001). In conclusion, gender disparity in caregiver responsibilities existed among highly skilled pediatric cardiologists even before the COVID-19 pandemic. The pandemic has disproportionately affected female pediatric cardiologists with respect to dependent care responsibilities, time at work, and financial compensation.

Post-Fontan pulmonary artery growth in patients with a bidirectional cavopulmonary shunt with additional antegrade pulsatile blood flow.

BACKGROUND: Patients with antegrade pulmonary blood flow after a bidirectional cavopulmonary shunt (Glenn) may have better pulmonary artery growth. This study evaluated pulmonary artery growth in patients with and without prior additional pulsatile antegrade flow in a Glenn shunt at midterm follow-up after a Fontan procedure. METHODS: We reviewed 212 patients who had single-ventricle palliation in a 10-year period;103 (33 in pulsatile group 1 and 70 in nonpulsatile group 2) were selected for analysis. Data on demographics, procedures, perioperative course, and midterm follow-up after the Fontan procedure were compared. Echocardiography data were collected. Pulmonary artery sizes measured at cardiac catheterization and follow-up echocardiograms were used to calculate the Nakata index. RESULTS: Perioperative details were comparable in both groups, mean pulmonary artery pressure and systemic oxygen saturations were higher in group 1 compared to group 2. Venovenous collaterals were increased in group 1. There was a significant difference in the pre-Fontan and follow-up Nakata index between groups. There was a significant increase in the Nakata index in group 1 between the pre-Glenn and pre-Fontan assessments as well as the Nakata index between the pre-Fontan and midterm follow-up. There was no significant change in the Nakata index in group 2 between assessments. CONCLUSIONS: A pulsatile Glenn shunt is associated with better pulmonary artery growth which continues long after the additional pulsatile flow is eliminated. It is possible that the effects of anterograde pulmonary blood flow on pulmonary artery growth in early life continue long after the Fontan completion.

Un-LINQed: Spontaneous extrusion of newer generation implantable loop recorders.

BACKGROUND: Insertable cardiac monitors (ICMs) are often used for long-term monitoring of cardiac rhythm. The Medtronic's LINQ Reveal ™ is a new generation wireless, automated, and patient responsive subcutaneous ECG monitoring device. Despite several advantages to its small size we have noted an unusually high incidence of extrusion at our center. METHODS: & Results: We conducted a retrospective case analysis to review Reveal LINQs implanted at our center. All devices were inserted using the provided insertion tools. Patients with extruded devices were identified and details regarding the site and technique of insertion, incision closure, use of peri-operative antibiotics, and follow-up details were collected. 81 patients underwent 85 Reveal LINQ implants at a tertiary care University Hospital referral center. The most common reason for implant was suspected arrhythmia with or without structural heart disease or unexplained syncope. There were 4 spontaneous extrusions occurring within 7-24 days after insertion with an incidence rate of 4.7%. One extruded device was anchored to subcutaneous tissue, and no pocket/device infections or hematomas were noted. CONCLUSIONS: Device migration and erosion through skin are important potential adverse events for the Reveal LINQ implantable loop recorder. This study reports an unexpectedly high rate of extrusion without infection. The authors suggest that the depth of the incision is the main factor impacting extrusions. Larger studies are recommended, however, and a proposed measure to avoid spontaneous extrusion is the design of a longer manufacturer's blade in order to increase the depth of the incision and insertion.

A novel familial truncating mutation in the filamin C gene associated with cardiac arrhythmias.

The authors report for the first time a novel mutation in the FLNC gene associated with cardiac arrhythmias in two half-siblings. The FLNC gene on chromosome 7q32 encodes filamin C, which stabilizes the actin network within the cardiomyocyte. The proband is an 8-year-old asymptomatic patient with frequent premature ventricular contractions noted on serial monitoring. Interestingly, the proband and his half-brother harbored a heterozygous 13 base pair deletion that resulted in a frameshift mutation and introduction of a premature stop codon. Notably, the proband also had a very tragic family history of sudden death in young individuals involving three generations and five family members. Because of their concerning family history and arrhythmias, both siblings underwent off-label implantable cardiac device placement for primary prevention of sudden cardiac death. Whether or not the FLNC mutation is associated with sudden cardiac death requires additional investigation and is beyond the scope of this manuscript. While previous studies have identified several mutations in the FLNC gene associated with dilated and hypertrophic cardiomyopathies, the goal of this study was to report a novel mutation in the FLNC gene that is associated with cardiac arrhythmias. The current study indicates that this mutation may help identify patients at risk for cardiac arrhythmias who would benefit from further cardiac evaluation.

Electrocardiogram Screening in Children with Congenital Sensorineural Hearing Loss: Prevalence and Follow-up of Abnormalities.

Objective The purpose is to determine the prevalence of electrocardiogram (ECG) abnormalities, including borderline and prolonged QT, among screened children with sensorineural hearing loss (SNHL) and to analyze their subsequent medical workup. Study Design Institutional Review Board-approved case series with chart review. Setting Tertiary academic center. Subjects and Methods Cases from 1996 to 2014 involving pediatric patients (N = 1994) with SNHL were analyzed. Abnormal ECGs were categorized as borderline/prolonged QT or other. A board-certified pediatric cardiologist retrospectively determined the clinical significance of ECG changes. For follow-up analysis, children with heart disease, known syndromes, or inaccessible records were excluded. Results Among 772 children who had ECGs, 215 (27.8%) had abnormal results: 35 (4.5%) with QT abnormalities and 180 (23.3%) with other abnormalities. For children with QT abnormalities meeting inclusion criteria (n = 30), follow-up measures included cardiology referral (46.6%), repeat ECG by ear, nose, and throat (ENT) specialist (20%), clearance by ENT specialist with clinical correlation and/or comparison with old ECGs (20%), and pediatrician follow-up (6.7%). Documentation of further workup by ENT or referral was absent for 6.7%. For children with other ECG changes meeting inclusion criteria (n = 136), abnormalities were documented for 57 (41.9%); normal QT without other abnormality was documented for 18 (13.2%). The most common follow-up referrals were to pediatricians (16.9%) and cardiologists (10.3%). Among patients with clinically significant non-QT abnormalities mandating further evaluation (n = 122), 38 (31.1%) had documented follow-up in medical records. Conclusion There is a high prevalence of ECG abnormalities among children with congenital SNHL. If findings are confirmed by future studies, screening should be considered for congenital unilateral or bilateral SNHL, regardless of severity. We describe a standardized protocol for ECG screening/follow-up.

Asymptomatic ventricular tachycardia: diagnostic pitfalls of Andersen-Tawil syndrome-a case report.

BACKGROUND: Andersen-Tawil syndrome (ATS) is a rare arrhythmia disorder caused by a mutation in the KCNJ2 gene. Typical presentation includes a triad of cardiac arrhythmia, dysmorphia, and periodic paralysis. However, KCNJ2 mutations can mimic other disorders such as catecholaminergic polymorphic ventricular tachycardia (CPVT) making treatment challenging. CASE SUMMARY: A 9-year-old asymptomatic female patient presented with an irregular heart rate noted at a well-child visit. Physical examination revealed short stature and facial dysmorphism. An initial rhythm strip showed intermittent runs of non-sustained bidirectional ventricular tachycardia with a prolonged QT interval of 485 ms at rest. Exercise testing showed no significant increase in ectopy from baseline at higher heart rates. Cardiac imaging was normal, and the burden of ventricular ectopy was significantly reduced on a beta-blocker and Class IC antiarrhythmic combination. Genetic testing marked a D71N mutation in the KCNJ2 gene. DISCUSSION: Clinical distinction between ATS and CPVT is a challenge. Genetic testing in the above patient attributed a likely pathogenic variant for both ATS and CPVT to a single D71N mutation in the KCNJ2 gene. Further evaluation revealed no clinical CPVT, emphasizing the need for cautious interpretation of genetic results in inherited arrhythmia disorders.

Improved Results of Aortic Arch Reconstruction in the Norwood Procedure.

BACKGROUND: Despite several surgical modifications, the reported incidence of neoaortic coarctation after stage 1 palliation (S1P) of hypoplastic left heart syndrome remains high. A modification of aortic arch reconstruction that may decrease the incidence of neoaortic coarctation after S1P is described. METHODS: Between January 2008 and May 2013, 114 patients with hypoplastic left heart syndrome underwent S1P. The hospital records of the 101 surviving patients (89%) were reviewed. Demographic data and perioperative variables for S1P were collected. A modified technique for aortic arch reconstruction that contains a bovine pericardial patch tailored and sutured in a specific way was used in 51 patients (group MT), whereas the traditional technique was used in 50 patients (group TT). Clinical echocardiographic and cardiac catheterization data were analyzed to determine the incidence and location of neoaortic coarctation. RESULTS: There were no significant differences in the baseline characteristics, the intraoperative course, or hospital mortality between the two groups of subjects. Duration of ventilation, intensive care unit stay, and hospitalization were significantly shorter in group MT. The mean follow-up was 2.02 ± 0.63 years and 3.98 ± 0.66 years in each group, respectively. Coarctation developed in 4 of 51 patients (7.8%) in group MT compared with 10/50 patients (20%) in group TT. Multivariable logistic regression analysis showed that the estimated odds of coarctation for group MT were 0.41 (95% confidence interval: 0.04, 4.32) times the estimated odds of coarctation for group TT. CONCLUSIONS: The described technique may decrease the incidence of recoarctation after S1P by minimizing aortic arch and descending aorta distortion and providing ample enlargement of the aorta at its narrowest diameter.

New oral anticoagulants: their role in stroke prevention in high-risk patients with atrial fibrillation.

Based on efficacy, safety, and ease of use, novel oral anticoagulants will likely replace VKAs for many if not most patients with atrial fibrillation. Novel anticoagulants have a lower rate of intracranial hemorrhage compared with vitamin K antagonists. The incidence of other life-threatening bleeds is similar if not lower. Dose adjustments need to be made based on renal function and advanced age. There is at present a need for an antidote for these new drugs.

Aortopathy in the 7q11.23 microduplication syndrome.

The 7q11.23 microduplication syndrome, caused by the reciprocal duplication of the Williams-Beuren syndrome deletion region, is a genomic disorder with an emerging clinical phenotype. Dysmorphic features, congenital anomalies, hypotonia, developmental delay highlighted by variable speech delay, and autistic features are characteristic findings. Congenital heart defects, most commonly patent ductus arteriosus, have been reported in a minority of cases. Included in the duplicated region is elastin (ELN), implicated as the cause of supravalvar aortic stenosis in patients with Williams-Beuren syndrome. Here we present a series of eight pediatric patients and one adult with 7q11.23 microduplication syndrome, all of whom had aortic dilation, the opposite vascular phenotype of the typical supravalvar aortic stenosis found in Williams-Beuren syndrome. The ascending aorta was most commonly involved, while dilation was less frequently identified at the aortic root and sinotubular junction. The findings in these patients support a recommendation for cardiovascular surveillance in patients with 7q11.23 microduplication syndrome.