Dobutamine Stress Cardiovascular Magnetic Resonance Derived 2-Dimension Feature Tracking Strain Analysis in Pediatric Population with Anomalous Aortic Origin of Right Coronary Artery.

Anomalous aortic origin of right coronary artery (AAORCA) is associated with myocardial ischemia and sudden cardiac arrest/death. Risk stratification remains challenging and relies upon provocative test results. This study describes the utility of dobutamine stress cardiovascular magnetic resonance (DSCMR) and potential benefit of strain analysis in children with AAORCA. All patients less than 21 years of age with AAORCA who underwent DSCMR between July 2018 and December 2022 were included. Visual wall motion abnormalities (VWMA) at rest and during protocolized increments of dobutamine infusion were assessed. Regional and global left ventricular circumferential (GCS) and radial (GRS) strain using 2-dimension Feature tracking (2D-FT) analysis (cvi42, Circle Cardiovascular Imaging Inc.) were calculated at rest and peak response. Of the total 54 DSCMR studies performed in 51 children with median age (IQR) of 13.5 (11-15) years, FT analysis was reliably performed in 52 (96%) studies. None had VWMA. The absolute change in GCS and GRS from rest to peak dobutamine stress was 4% (1-6%) and 11% (4-18%), respectively. There was no significant difference in GCS and GRS in patients with exertional symptoms vs no/non-exertional symptoms as well as between those considered to be high-risk vs low-risk anatomical features. DSCMR-derived 2D-FT strain analysis is feasible to assess myocardial deformation in children with AAORCA and may enhance this method of provocative testing. Although there were no statically significant differences in GCS and GRS values between high and low-risk subgroups, the absolute change in GCS between rest and peak stress is diminished when compared to normal adult reports.

Tolerability and efficacy of a reduced dose adenosine stress cardiac magnetic resonance protocol under general anesthesia in infants and children.

BACKGROUND: Intravenous adenosine induces pharmacological stress by causing vasodilatation and thus carries the risk of severe hypotension when combined with vasodilatory effects of anesthetic agents. OBJECTIVE: This study describes our experience with a reduced dose adenosine cardiac magnetic resonance imaging (MRI) protocol in young children under general anesthesia (GA). MATERIALS AND METHODS: This is a retrospective report of all patients from birth to 18 years who underwent adenosine stress cardiac MRI under GA between August 2018 and November 2022. Based on our anecdotal experience of severe adverse effects in patients receiving adenosine infusion under GA and in discussion with the pediatric anesthesia team, we developed a modified protocol starting at a dose of 110 mcg/kg/min with incremental escalation to a full dose of 140 mcg/kg/min to achieve desired hemodynamic effect. RESULTS: Twenty-two children (mean age 6.5 years, mean weight 28 kg) satisfied the inclusion criteria. The diagnoses included Kawasaki disease (7), anomalous aortic origin of left coronary artery (3), anomalous aortic origin of right coronary artery (2), coronary fistula (3), repaired d-transposition of great arteries (2), repaired anomalous left coronary artery from pulmonary artery (2), repaired truncus arteriosus with left coronary artery occlusion (1), extracardiac-Fontan with left coronary artery myocardial bridge (1), and post heart transplantation (1). Nine patients needed dose escalation beyond 110 mcg/kg/min. Two patients had transient hypotension during testing (systemic blood pressure drop > 25 mmHg). No patient developed significant heart block or bronchospasm. Six patients (repeat study in one) demonstrated inducible perfusion defects (27%) on stress perfusion sequences-5 of whom had confirmed significant coronary abnormalities on angiography or direct surgical inspection. CONCLUSION: A reduced/incremental dose adenosine stress cardiac MRI protocol under GA in children is safe and feasible. This avoids severe hypotension which is both unsafe and may result in inaccurate data.

Diagnosis and Management of Congenital Coronary Artery Fistulas in Infants and Children.

PURPOSE OF REVIEW: Coronary artery fistulas (CAFs) are rare coronary anomalies that most often occur as congenital malformations in children. Although most children with CAFs are asymptomatic at the time of diagnosis, some present with symptoms of congestive heart failure in the setting of large left-to-right shunts. Others may develop additional complications including coronary artery ectasia and coronary thrombosis. Surgical and transcatheter closure techniques have been previously described. This review presents the classifications of CAFs in children and the short and long-term outcomes of CAF closure in children in the reported literature. We also summarize previously-reported angiographic findings and post-treatment remodeling characteristics in pediatric patients. RECENT FINDINGS: With advancements in cross-sectional imaging technologies, anatomic delineation of CAFs via these modalities has become crucial in procedural planning. Recent reports of surgical and transcatheter closure of CAFs in children have reported good procedural success and low rates of short-term morbidity and mortality. Distal-type CAFs have elevated risk for long-term sequelae post-closure compared to proximal-type CAFs. A recent report of a multi-institutional cohort also describes post-closure remodeling classifications which may predict long-term outcomes in these patients as well as guide individualized anticoagulation management. Invasive closure of significant CAFs via surgical or transcatheter techniques is feasible and safe in most children with good short and intermediate-term outcomes. However, close clinical and imaging follow-up is required to monitor for late complications even after successful closure. Antiplatelet and anticoagulation regimens remain important aspects of post-closure management, but the necessary intensity and duration of such therapy remains unknown.

Value of Time-Resolved Cardiac CT in Children and Young Adults with Congenital Heart Disease and Infective Endocarditis.

BACKGROUND: Diagnosis of infective endocarditis (IE) can be challenging due to negative blood cultures and diagnostic limitations of various imaging modalities. Transesophageal echocardiography (TEE) is the gold standard imaging modality for visualization of valvular vegetations. However, due to the anterior location of the pulmonary valve, post-surgical changes, and sedation requirement, TEE can be challenging in the pediatric population. The aim of this study was to assess the value of Cardiac CT (CCT) for diagnosis of IE in children and young adults with congenital heart disease (CHD). METHODS: This is a single-center retrospective study of pediatric patients with CHD and diagnosis of IE who underwent CCT from 2018 to 2022. Data collected included age, gender, cardiac diagnosis, clinical presentation, echocardiographic/CCT findings, and blood culture results. In addition, modified Duke criteria (MDC) for the diagnosis of IE were applied with and without CCT findings as the diagnostic imaging criterion. RESULTS: Fourteen patients were included in this study with a median age of 11 years old. Nine patients were female. Ten patients had IE of the RV-PA conduit and four patients had IE of the aortic valve. Using MDC, 4 patients had definite IE. After including CCT findings, 11 patients (79%) met MDC for definite IE. Blood cultures were positive in 12 patients. CCT revealed the following complications: thromboembolic findings/pseudoaneurysms in 5 patients each and prosthetic valve perforation/prosthetic valve leak in one patient each. CONCLUSIONS: This study reinforces the complimentary role of CCT to echocardiography in the work-up and diagnosis of IE in patients with CHD. With further improvement in lowering radiation exposure, CCT may have a key role in the diagnostic work-up of endocarditis and could be implemented in the diagnostic criteria of IE.

Diagnostic Accuracy and Safety of Confirm Rx™ Insertable Cardiac Monitor in Pediatric Patients.

Insertable cardiac monitors (ICM) are subcutaneously implanted devices that monitor a patient's heart rate and rhythm (Rossano in Pediatrics 112(3):e228, 2003). The diagnostic accuracy and safety of the Confirm RxTM (Abbott, Minneapolis, MN) ICM in pediatric patients is unknown. This is a single center, retrospective, IRB-approved review of patients ≤ 21 years implanted with Confirm RxTM ICMs from 2017 to 2020. Data collected included demographics, indications, presence of P-wave and R-wave amplitude at implantation and follow-up, number/appropriateness of transmissions pre and post implementation of SharpSenseTM technology, reprogramming to improve accuracy, time from implantation to arrhythmia detection, and complications. There were 29 patients (median age: 8 years, 59% females). P-waves were identified in all patients and average R-wave amplitude was 0.85 mV (0.26-1.03 mV). There was no significant difference in R-wave amplitude based on size (BSA ≥ 1.5 m2: 0.76 mV, < 1.5 m2: 0.91 mV) or congenital heart disease (+CHD: 0.86 mV, -CHD: 0.85 mV). Arrhythmias identified were the following: wide complex tachycardia (1), supraventricular tachycardia (4), bradycardia/sinus pause (3), and premature ventricular contraction (1). SharpSenseTM implementation decreased the false-positive rate in device-initiated transmissions (55.4% to 0%, p < 0.00001). Average time from implantation to arrhythmia detection was 2.63 months (range: 0-8.8). A single complication of cellulitis occurred. Confirm RxTM is appropriate for implant in pediatric patients regardless of age, BSA, or CHD. Implementation of SharpSense™ technology dramatically decreased the false-positive rate. Follow-up studies could utilize additional monitoring devices to provide analysis on potential events that the Confirm RxTM ICM missed.

Appropriate use of echocardiography for palpitations in paediatric cardiology clinics.

OBJECTIVES: Identify diagnostic yield and frequency of echocardiograms for palpitation-related indications at outpatient paediatric cardiology clinics in relation to the 2014 ACC/AAP/AHA/ASE/HRS/SCAI/SCCT/SCMR/SOPE appropriate use criteria for Initial Transthoracic Echocardiography in Outpatient Paediatric Cardiology. STUDY DESIGN: A single-centre, retrospective study of children presenting for evaluation of a chief complaint of palpitations to outpatient paediatric cardiology clinics from 2015 to 2017. Palpitations were defined as an unpleasant sensation of rapid, irregular, and/or forceful beating of the heart. Indications for echocardiogram in patients were retrospectively classified based on the appropriate use criteria as "appropriate," "may be appropriate," or "rarely appropriate." The incidence of abnormal and incidental echocardiographic findings for each category was determined. RESULTS: A total of 286 patients presented with palpitations, with 128 (52% female) meeting inclusion criteria. Exclusion criteria included patients with additional cardiac complaints, prior echocardiogram, or history of congenital heart disease. Echocardiograms were performed on 36 (28%) patients. The appropriate use criteria were retrospectively applied, and indications for their performance were classified as "appropriate" (n = 4), "may be appropriate" (n = 17), or "rarely appropriate" (n = 15). Minor echocardiographic abnormalities were present in 22% (n = 8) of echocardiograms obtained for all appropriate use criteria classifications. No moderate or severe echocardiographic abnormalities were found. Incidental findings were noted in eight echocardiograms. CONCLUSION: Echocardiography in the evaluation of "rarely appropriate" and "may be appropriate" palpitation-related indications is of low diagnostic yield.

Evidence-based medicine: a persisting desire under fire.

Healthcare infrastructure and medical schools in Syria have been greatly compromised by military conflict and humanitarian disaster. Medical students and healthcare professionals reached out for remote learning opportunities. Surprisingly, they desired a curriculum in evidence-based medicine. We report on a curriculum that was delivered to 126 learners using an online remote delivery platform. This experience demonstrates the feasibility of this approach in disaster-stricken areas and underscores the importance of evidence-based medicine even under such conditions.

Wearable Biosensors in Congenital Heart Disease: Needs to Advance the Field.

Traditional measures of clinical status and physiology have generally been based in health care settings, episodic, short in duration, and performed at rest. Wearable biosensors provide an opportunity to obtain continuous non-invasive physiologic data from patients with congenital heart disease (CHD) in the real-world setting, over longer durations, and across varying levels of activity. However, there are significant technical limitations to the use of wearable biosensors in CHD. Here, we review current applications of wearable biosensors in CHD; how clinical and research uses of wearable biosensors must consider various CHD physiologies; the technical challenges in developing wearable biosensors for CHD; and special considerations for digital biomarkers in CHD.

Velocity encoded mitral valve inflow cine: A novel and more reproducible method to determine cardiac rest periods during coronary magnetic resonance angiography.

A high temporal resolution, 4-chamber (4CH) cine is the standard method for determining cardiac rest periods during whole heart coronary magnetic resonance angiography (CMRA). We evaluated the image quality and reproducibility between the 4CH cine method and a novel approach using a velocity encoded mitral valve inflow cine (MVI). The goal of this study was to compare the quality of CMRAs utilizing MVI versus 4CH methods. Sharpness and vessel length for the LCA and RCA using each method were determined using Soap Bubble and two blinded observers independently assessed coronary image quality. Offline analysis on a separate, retrospective cohort (n = 25) was used to compare MVI and 4CH reproducibility. In the prospectively evaluated cohort there was no difference in overall vessel sharpness (4CH vs MVI mean ± SD) (31.0 ± 5.5% vs 30.5 ± 5.7%, p = .63), LCA vessel sharpness (30.0 ± 5.4% vs 31.1 ± 8.2%, p = .44), LCA length (4.7 ± 1.4 cm vs 4.6 ± 1.6 cm, p = .66), RCA vessel sharpness (32.1 ± 6.9% vs 31.1 ± 7.7%, p = .55), RCA length (5.51 ± 2.6 cm vs 5.95 ± 2.4 cm, p = .38), or image quality rating (2.66 vs 2.62, p = .80) between methods. In the retrospective cohort, the MVI method had 5.4% lower inter-observer variability (95% CI 3.7,7.2%, p < .0001) and 3.9% lower intra-observer variability (95% CI 2.4,5.4%, p < .0001) than the 4CH method. MVI is a technically feasible and more reproducible method to determine cardiac rest periods compared to 4CH while preserving vessel sharpness, vessel length & image quality.

Myocardial Parametric Mapping by Cardiac Magnetic Resonance Imaging in Pediatric Cardiology and Congenital Heart Disease.

Parametric mapping, that is, a pixel-wise map of magnetic relaxation parameters, expands the diagnostic potential of cardiac magnetic resonance by enabling quantification of myocardial tissue-specific magnetic relaxation on an absolute scale. Parametric mapping includes T1 mapping (native and postcontrast), T2 and T2* mapping, and extracellular volume measurements. The myocardial composition is altered in various disease states affecting its inherent magnetic properties and thus the myocardial relaxation times that can be directly quantified using parametric mapping. Parametric mapping helps in the diagnosis of nonfocal disease states and allows for longitudinal disease monitoring, evaluating therapeutic response (as in Thalassemia patients with iron overload undergoing chelation), and risk-stratification of certain diseases. In this review article, we describe various mapping techniques and their clinical utility in congenital heart disease. We will also review the available literature on normative values in children, the strengths, and weaknesses of these techniques. This review provides a starting point for pediatric cardiologists to understand and implement parametric mapping in their practice.

Wearable Seismocardiography-Based Assessment of Stroke Volume in Congenital Heart Disease.

Background Patients with congenital heart disease (CHD) are at risk for the development of low cardiac output and other physiologic derangements, which could be detected early through continuous stroke volume (SV) measurement. Unfortunately, existing SV measurement methods are limited in the clinic because of their invasiveness (eg, thermodilution), location (eg, cardiac magnetic resonance imaging), or unreliability (eg, bioimpedance). Multimodal wearable sensing, leveraging the seismocardiogram, a sternal vibration signal associated with cardiomechanical activity, offers a means to monitoring SV conveniently, affordably, and continuously. However, it has not been evaluated in a population with significant anatomical and physiological differences (ie, children with CHD) or compared against a true gold standard (ie, cardiac magnetic resonance). Here, we present the feasibility of wearable estimation of SV in a diverse CHD population (N=45 patients). Methods and Results We used our chest-worn wearable biosensor to measure baseline ECG and seismocardiogram signals from patients with CHD before and after their routine cardiovascular magnetic resonance imaging, and derived features from the measured signals, predominantly systolic time intervals, to estimate SV using ridge regression. Wearable signal features achieved acceptable SV estimation (28% error with respect to cardiovascular magnetic resonance imaging) in a held-out test set, per cardiac output measurement guidelines, with a root-mean-square error of 11.48 mL and R2 of 0.76. Additionally, we observed that using a combination of electrical and cardiomechanical features surpassed the performance of either modality alone. Conclusions A convenient wearable biosensor that estimates SV enables remote monitoring of cardiac function and may potentially help identify decompensation in patients with CHD.

Pharmacologic stress cardiovascular magnetic resonance in the pediatric population: A review of the literature, proposed protocol, and two examples in patients with Kawasaki disease.

Pharmacologic stress cardiovascular magnetic resonance (PSCMR) is a well-established and reliable diagnostic tool for evaluation of coronary artery disease in the adult population. Stress imaging overall and PSCMR in particular is less utilized in the pediatric population with limited reported data. In this review, we highlight the potential use of PSCMR in specific pediatric cohorts with congenital and acquired heart disease, and we review the reported experience. A suggested protocol is presented in addition to two case examples of patients with Kawasaki disease where PSCMR aided decision making.

First-Line Antiarrhythmic Transplacental Treatment for Fetal Tachyarrhythmia: A Systematic Review and Meta-Analysis.

BACKGROUND: There is no consensus on the most effective and best tolerated first-line antiarrhythmic treatment for fetal tachyarrhythmia. The purpose of this systematic review and meta-analysis was to compare the efficacy, safety, and fetal-maternal tolerance of first-line monotherapies for fetal supraventricular tachycardia and atrial flutter. METHODS AND RESULTS: A comprehensive search of several databases was conducted through January 2017. Only studies that made a direct comparison between first-line treatments of fetal tachyarrhythmia were included. Outcomes of interest were termination of fetal tachyarrhythmia, fetal demise, and maternal complications. Ten studies met inclusion criteria, with 537 patients. Overall, 291 patients were treated with digoxin, 137 with flecainide, 102 with sotalol, and 7 with amiodarone. Digoxin achieved a lower rate of supraventricular tachycardia termination compared with flecainide (odds ratio [OR]: 0.773; 95% confidence interval [CI], 0.605-0.987; I2=34%). In fetuses with hydrops fetalis, digoxin had lower rates of tachycardia termination compared with flecainide (OR: 0.412; 95% CI, 0.268-0.632; I2=0%). There was no significant difference in the incidence of maternal side effects between digoxin and flecainide groups (OR: 1.134; 95% CI, 0.129-9.935; I2=80.79%). The incidence of maternal side effects was higher in patients treated with digoxin compared with sotalol (OR: 3.148; 95% CI, 1.468-6.751; I2=0%). There was no difference in fetal demise between flecainide and digoxin (OR: 0.767; 95% CI, 0.140-4.197; I2=44%). CONCLUSIONS: Flecainide may be more effective treatment than digoxin as a first-line treatment for fetal supraventricular tachycardia.

Systematic Reviews and Meta-analyses for Cardiology Fellows.

Participating in a scholarly activity is one of the training requirements for cardiology fellows. However, it can be very challenging to complete a research project during such a busy period of clinical training. To help the cardiology fellows in choosing and starting off a research project, a light has been shed on the process of conducting a systematic review, and the importance of this research activity, as well as its limitations.

Vitamin D supplementation in children with asthma: a systematic review and meta-analysis.

BACKGROUND: Epidemiologic studies suggest an association between vitamin D deficiency and atopic diseases, including asthma. The objective of this study was to systematically review the benefits and harms of vitamin D supplementation in children with asthma. METHODS: We used standard Cochrane systematic review methodology. The search strategy included an electronic search in February 2013 of MEDLINE and EMBASE. Two reviewers completed in duplicate and independently study selection, data abstraction, and assessment of risk of bias. We pooled the results of trials using a random-effects model. We assessed the quality of evidence by outcome using the GRADE methodology. RESULTS: Four trials with a total of 149 children met eligibility criteria. The trials had major methodological limitations. Given the four studies reporting on asthma symptoms used different instruments to measure that outcome, we opted not to conduct a meta-analysis. Three of those studies reported improvement in asthma symptoms in the vitamin D supplemented group study, while the fourth reported no effect (very low quality evidence). For the lung function outcome, a meta-analysis of two trials assessing post treatment FEV-1 found a mean difference of 0.54 liters per second (95% CI -5.28; 4.19; low quality evidence). For the vitamin D level outcome, a meta-analysis of three trials found a mean difference of 6.56 ng/ml (95% CI -0.64; 13.77; very low quality evidence). CONCLUSIONS: The available very low to low quality evidence does not confirm or rule out beneficial effects of vitamin D supplementation in children with asthma. Large-scale, well-designed and executed randomized controlled trials are needed to better understand the effectiveness and safety of vitamin D in children with asthma.

An assessment of diabetes care in Palestinian refugee camps in Syria.

BACKGROUND: Palestinian refugees have been a displaced group of people since 1948, many of whom are living in refugee camps in the Middle East. They are entitled to free health care from the United Nations Relief and Work Agency (UNRWA). They show a higher prevalence of diabetes than the population in their host countries in the Middle East. This study examined the realities of care for diabetic patients in UNRWA health clinics in Damascus, Syria. The aim was three-fold: To investigate the level of diabetes care, to probe patients' level of general understanding of their disease and its management, and to search for areas of potential improvement. METHODS: Data on patient education and care was gathered over a 1 month period from August 4, 2008 to September 4, 2008 using questionnaires and direct observation of the workflow at the clinics. Clinic-led care was observed by the study team using checklists during patient visits. All of the clinic staff and sampled patients were interviewed. The main areas of care assessed were: Patient follow-up; examination of eyes and feet; availability of medications; and patient education. A total of 154 people with diabetes were sampled from three refugee camps situated around Damascus. RESULTS: A total of 154 patients, three doctors and seven nurses composed the sample of the study. Foot examinations were almost always neglected by health staff and eye examinations were not offered by the UNRWA clinics. Interviews with patients showed that: 67% (95% confidence intervals [CI]: 0.59-0.70) had to buy their medication at their own expense at least once due to medication shortage in the UNRWA clinics, 48% (95% CI: 0.40-0.55) displayed poor knowledge regarding the cause and exacerbating factors of diabetes, 65% (95% CI: 0.56-0.72) had not heard of insulin, and 43% (95% CI: 0.35-0.51) did not know for how long they needed to take their medications.

Association between low vitamin D levels and the diagnosis of asthma in children: a systematic review of cohort studies.

BACKGROUND: There is conflicting evidence about the association between low vitamin D levels in children and development of asthma in later life. The objective of this study was to systematically review the evidence for an epidemiological association between low serum levels of vitamin D and the diagnosis of asthma in children. METHODS: We used the Cochrane methodology for conducting systematic reviews. The search strategy included an electronic search of MEDLINE and EMBASE in February 2013. Two reviewers completed, in duplicate and independently, study selection, data abstraction, and assessment of risk of bias. RESULTS: Of 1081 identified citations, three cohort studies met eligibility criteria. Two studies found that low serum vitamin D level is associated with an increased risk of developing asthma late in childhood, while the third study found no association with either vitamin D2 or vitamin D3 levels. All three studies suffer from major methodological shortcomings that limit our confidence in their results. CONCLUSIONS: Available epidemiological evidence suggests a potential association between low serum levels of vitamin D and the diagnosis of asthma in children. High quality studies are needed to reliably answer the question of interest.