Assessing Left Ventricular Pathology in Patients with Ebstein Anomaly Using Cardiovascular Magnetic Resonance: Looking Past the Right Heart.

Ebstein Anomaly (EA) is a malformation of the right heart, but there is data to suggest that the left ventricle (LV) can suffer from intrinsic structural and functional abnormalities which affect surgical outcomes. The LV in patients with EA is hypertrabeculated with abnormalities in LV function and strain. In this retrospective single-center study, patients with EA who underwent pre-operative cardiac MRI (CMR) between the periods of 2014-2024 were included along with a group of healthy-age-matched controls. Left ventricular and right ventricular volume, function and strain analyses were performed on standard SSFP imaging. LV noncompacted: compacted (NC/C) ratio and the displacement index of the tricuspid valve were measured. Forty-seven EA patients were included with mean age of 21.0 ± 17.6 years. Seventeen EA patients (36%) had mild pre-operative LV dysfunction on CMR and 1 (2.1%) had moderate LV dysfunction. Out of these 18 patients with LV dysfunction, only 2 were detected to have dysfunction on Echocardiogram. The global circumferential and longitudinal strain were significantly lower in the reduced LVEF group compared to those with preserved LVEF (- 14.8% vs. - 17%, p = 0.02 and - 11.9% vs. - 15.0%; p = 0.05; respectively) on CMR. A single EA patient met criteria for LVNC with a maximal NC/C ratio > 2.3. There was no statistically significant difference in NC/C ratio in the EA population (1.4 ± 0.6) vs. controls (1.1 ± 0.2), p = 0.17. There was an inverse correlation of LV ejection fraction with right ventricular end-diastolic volume and displacement index. All patients underwent the Da Silva Cone procedure at our center. Patients with preoperative LV dysfunction had longer duration of epinephrine use in the immediate postoperative period (33.7 ± 21.4 vs 10.2 ± 25.6 h, p = 0.02) and longer length of hospital stay (6.3 ± 3.2 vs 4.4 ± 1.2 days, p = 0.01). This is the largest study to date to evaluate preoperative LV structure and function in EA patients by CMR. In this cohort of 47 patients, preoperative LV dysfunction is fairly common and CMR has high sensitivity in detecting LV dysfunction as compared to Echo. True LV non-compaction was rare in this cohort. The presence of LV dysfunction is relevant to perioperative management and further study with larger cohorts and longer follow up are necessary.

Large Right Atrial Size on Cardiac MRI is Associated with Post-operative Right Ventricular Dysfunction After the Cone Operation for Ebstein Anomaly.

The cone operation has revolutionized care for patients with Ebstein anomaly; however, acute post-operative right ventricular dysfunction (RVD) is common in this patient population. A single-center, retrospective review of 28 patients with Ebstein anomaly who underwent cardiac MRI (CMR) prior to cone reconstruction of the tricuspid valve was conducted. Measurements of atrial and ventricular size/function were assessed. Post-operative RVD was defined as the presence of moderate or severe systolic dysfunction on discharge echo. A two-tail t test was employed to compare the two groups. The average age at operation was 21.4 years (range 1.6-57.8) and 14 (50%) had RVD at discharge. Patients with post-operative RVD had significantly larger pre-operative right atrial (RA) maximum volume (p = 0.016) and RA minimum volume (p = 0.030). Patients with RVD had smaller pre-operative left atrial (LA) minimum volume (p = 0.012). Larger pre-operative right ventricular (RV) end-systolic volume (p = 0.046), lower RV ejection fraction (0.029), and smaller left ventricular (LV) end-diastolic volume (p = 0.049) were significantly associated with post-operative RVD. Post-operative RVD was associated with longer milrinone duration (p = 0.009) and higher maximum milrinone dose (p = 0.005) but was not associated with intensive care or hospital length of stay (p = 0.19 and 0.67, respectively). Increased RA and RV dilation and decreased LA and LV volumes are associated with the development of post-operative RVD following cone operation for Ebstein anomaly. Post-operative RVD affects milrinone dose and duration but is not associated with increased length of stay.

The effect of geographic origin and destination on congenital heart disease outcomes: a retrospective cohort study.

BACKGROUND: Congenital heart disease (CHD) is a common and significant birth defect, frequently requiring surgical intervention. For beneficiaries of the Department of Defense, a new diagnosis of CHD may occur while living at rural duty stations. Choice of tertiary care center becomes a function of geography, referring provider recommendations, and patient preference. METHODS: Using billing data from the Military Health System over a 5-year period, outcomes for beneficiaries age < 10 years undergoing CHD surgery were compared by patient origin (rural versus urban residence) and the distance to treatment (patient's home and the treating tertiary care center). These beneficiaries include children of active duty, activated reserves, and federally activated National Guard service members. Analysis of the outcomes were adjusted for procedure complexity risk. Treatment centers were further stratified by annual case volume and whether they publicly reported results in the society of thoracic surgery (STS) outcomes database. RESULTS: While increasing distance was associated with the cost of admission, there was no associated risk of inpatient mortality, one year mortality, or increased length of stay. Likewise, rural origination was not significantly associated with target outcomes. Patients traveled farther for STS-reporting centers (STS-pr), particularly high-volume centers. Such high-volume centers (> 50 high complexity cases annually) demonstrated decreased one year mortality, but increased cost and length of stay. CONCLUSIONS: Together, these findings contribute to the national conversation of rural community medicine versus regionalized subspecialty care; separation of patients between rural areas and more urban locations for initial CHD surgical care does not increase their mortality risk. In fact, traveling to high volume centers may have an associated mortality benefit.

Using DaSilva Cone Operation to Establish 1.5 or 2 Ventricle Circulation After Initial Single Ventricle Palliation with Starnes Procedure.

Ebstein anomaly (EA) is a congenital dysplasia of the tricuspid valve resulting in reduced right ventricular (RV) volume and tricuspid regurgitation. Severe EA in the neonatal period is associated with high mortality. The Starnes procedure (fenestrated RV exclusion) is reserved for EA patients with cardiogenic shock and has previously committed patients to single ventricle (SV) palliation. In this report, we present the results of a strategy to redirect patients utilizing the Da Silva Cone operation to achieve a 2 or 1.5 ventricle circulation. Single-center retrospective study including all consecutive cases of Da Silva Cone operation after Starnes procedure. Between 2019 and 2023, six conversions from Starnes procedure to Cone reconstruction were performed. All were critically ill before their Starnes procedure; four on extracorporeal membrane oxygenation. Two patients were successfully rerouted to a two-ventricle repair; the remainder to 1.5 ventricle circulation. RV pressure estimates showed no correlation with success. Post-Cone intensive care and hospital stays were brief, median 5 and 6 days, respectively. All are between 2.5 and 6 years old, without indications for SV palliation. There were no deaths, with follow up ranging 1 month-4 years. No repeat interventions were performed on the tricuspid valves. One subject had a surgical pulmonary valve replacement. Tricuspid regurgitation was mild in all. The Da Silva Cone operation offers successful redirection of EA patients from a SV pathway to a 1.5 or 2 ventricle pathway after Starnes procedure. The approach is feasible and durable in midterm follow-up. The decision to initially proceed with Starnes need not be an irrevocable decision to continue down a SV palliation pathway.

Hypertension Prevalence, Cardiac Complications, and Antihypertensive Medication Use in Children.

OBJECTIVE: To determine the prevalence of hypertension diagnosis in children of US military members and quantify echocardiography evaluations, cardiac complications, and antihypertensive prescriptions in the post-2004 guideline era. STUDY DESIGN: Using billing data from military health insurance (TRICARE) enrollees, hypertension cases were defined as 2 or more visits with a primary or unspecified hypertension diagnosis during any calendar year or 1 such visit if with a cardiologist or nephrologist. RESULTS: During 2006-2011, the database contained an average 1.3 million subjects aged 2-18 years per year. A total of 16 322 met the definition of hypertension (2.6/1000). The incidence of hypertension increased by 17% between 2006 and 2011 (from 2.3/1000 to 2.7/1000; P < .001). Hypertension was more common in adolescents aged 12-18 years than in younger children (5.4/1000 vs 0.9/1000). Among patients with hypertension, 5585 (34%) underwent echocardiography. The frequency of annual echocardiograms increased from 22.7% to 27.7% (P < .001). In patients with echocardiography, 8.0% had left ventricular hypertrophy or dysfunction. Among the patients with hypertension, 6353 (38.9%) received an antihypertensive medication. CONCLUSION: The prevalence of hypertension in children has increased. Compliance with national guidelines is poor. Of pediatric patients with hypertension who receive an echocardiogram, 1 in 12 had identified cardiac complications, supporting the current recommendations for echocardiography in children with hypertension. Less than one-half of children with hypertension are treated with medication.

Cardiac Causes of Sudden Unexpected Infant Death and the Role of the Primary Pediatrician.

Sudden death of an infant can be from numerous causes. The leading cardiac causes include major congenital heart disease, myocarditis, cardiomyopathies, and channelopathies. There are new approaches to evaluating these patients and surviving family members. Pediatricians are a key component in support of the family, investigation of other at-risk family members, and coordination of subspecialty consultation. [Ped Ann. 2022;51(6):e228-e233.].

Cardiac Sequelae of COVID-19 in Children and Young Adults.

Coronavirus disease 2019 (COVID-19) has a predilection to cardiac involvement. The early clinical phase, during viremia, may manifest as pericarditis, acute myocarditis, and sepsis-related cardiomyopathy. Delayed presentations, such as multisystem inflammatory syndrome in children, coronary artery dilation/aneurysms, and late myocarditis, may occur in the weeks after the acute infection. These delayed presentations commonly test negative for severe acute respiratory syndrome coronavirus 2 via polymerase chain reaction testing and are thought to be primarily postviral hyperinflammatory sequelae. The long-term consequences of cardiac involvement in COVID-19 are unknown. Most recommendations for cardiac management are based on known conditions that are similar. For example, coronary aneurysms can be managed under Kawasaki disease guidelines. Similarly, for patients with COVID-19 myocarditis, they can be cleared for sports under protocols for other types of myocarditis. There is concern for cardiac involvement as a subclinical entity even in more minor presentations. Several expert algorithms have been developed for clearing competition athletes to return to exercise. Sports clearance should be individualized considering the severity of disease, age of patient, and performance level of the sport. [Pediatr Ann. 2021;50(3):e128-e135.].

Reduction in Medical Evacuations from Iraq and Syria Following Introduction of an Asynchronous Telehealth System.

INTRODUCTION: While deployed, military medical personnel manage routine medical issues that fall under the category of Disease Non-Battle Injury (DNBI). The 86th Combat Support Hospital (CSH) partnered with Combined Joint Task Force-Operation Inherent Resolve (CJTF-OIR) Surgeon Cell, and Special Operations Joint Task Force-Operation Inherent Resolve (SOJTF-OIR) Surgeon Cell, to introduce the Health Experts onLine Portal (HELP) telemedicine system to medical personnel in Iraq and Syria. HELP is an asynchronous (store and forward) online system that provides secure provider-to-provider teleconsultation services for routine patient care and medical evacuation (MEDEVAC) coordination. The goal was to reduce the need for MEDEVAC by providing expert consultation to medical providers in farther-forward deployed units. MATERIAL AND METHODS: In June 2017, the 86th CSH launched HELP telemedicine services for Kuwait. Following the successful implementation of the telemedicine system in Kuwait, the 86th CSH leadership partnered with CJTF-OIR and SOJTF-OIR medical leadership in launching the system within Iraq and Syria as well as making the system available to all deployed locations in Central Command (CENTCOM). This was a prospective cohort study designed to determine if having convenient and secure access to remote subspecialty consultation would be associated with a reduction in routine MEDEVACs from far forward in the battle space. In August 2017, new-user training was completed and the program launched in Iraq and Syria. This study analyzes the baseline MEDEVAC rate in 3 months before the implementation of HELP telemedicine compared to 3 months following the implementation. RESULTS: Iraq and Syria cases in the HELP telemedicine system accounted for 17.2% (76) of total CENTCOM telemedicine case volume over the 7-month study period. Comparing the 3-month period before and after implementation of HELP, use of asynchronous telemedicine in Iraq and Syria was associated with a reduction in total MEDEVACs from 157 to 68 (56.7% reduction, p < 0.001). DNBI represented the majority of the change, (65.0% reduction, p < 0.001). MEDEVAC for battle-related injuries decreased slightly from 13 to 6 per 3-month period (p = 0.03). CONCLUSIONS: This is the first prospective study to demonstrate an association between the initiation of asynchronous telemedicine capabilities in a combat zone and decreased MEDEVACs. Annualized numbers would predict a reduction of 328 MEDEVACs/year for each 10,000 personnel by utilizing asynchronous telemedicine. This represents a significant potential cost savings of $1.2 million/year through avoidance of routine medical movement of personnel and supports unit readiness by retaining service members in areas of combat operations.

Exercise Dose Associated With Military Service: Implications for the Clinical Management of Inherited Risk for Arrhythmogenic Right Ventricular Cardiomyopathy.

INTRODUCTION: High levels of aerobic exercise in individuals who have a gene mutation associated with arrhythmogenic right ventricular cardiomyopathy (ARVC) are associated with clinical disease progression. Guidelines consequently restrict patients from competitive athletics. However, there is minimal literature to guide the safe dosing of physical activity outside of the setting of competitive athletics. Patients may be physically active pursuant to a variety of careers, including military service. This study aimed to define a therapeutic window for exercise for ARVC gene-positive individuals that are compatible with continuing military service and general health while maintaining a level of exercise below that which risks disease progression. MATERIALS AND METHODS: Using standard metabolic equations, we calculated the minimum VO2 max (amount of oxygen utilized at peak exercise capacity) required to pass the physical fitness tests for each branch. We then developed a sample exercise prescription to maintain this level of fitness. We compared the prescribed exercise load with the physical activity levels associated with non-inferior clinical outcomes in ARVC gene-positive individuals. Additionally, we determined the physical activity exposure sustained by service members based on self-report data and compared these values with the upper limit of safe exercise exposure. RESULTS: Based on a review of the currently available literature, aerobic exercise exposure less than 700 to 1,100 MET-hours/year (metabolic equivalent-hours per year) is not associated with inferior clinical outcomes for gene-positive individuals. A military service member needs 600 to 700 MET-hours/year to minimally pass the physical fitness test. However, many military members are exercising in excess of this minimum, with typical exposures between 900 and 2,400 MET-hours/year. CONCLUSIONS: A therapeutic window of aerobic exercise may exist for ARVC gene-positive individuals which would allow continuation of military service while maintaining levels of exercise restriction associated with non-inferior clinical outcomes.

24-hour QT variability in heart failure.

BACKGROUND: Previous studies have shown that increased temporal variability of repolarization, as reflected by QT interval variability measured for 10 minutes, predicted spontaneous ventricular arrhythmias in implantable cardioverter defribrillator patients, but it is unclear how these measures perform in 24-hour recordings. METHODS: Twenty-four-hour digital Holter recordings from 372 subjects with chronic heart failure enrolled in Gruppo Italiano per lo Studio della Sopravvivenza nell'Insufficienza Cardiaca, (GISSI) Heart Failure study were analyzed using a template-matching, semiautomatic algorithm to measure QT and heart rate time series in sequential 5-minute epochs for 24 hours. QT variability was expressed as normalized QT variance (QTVN) or as the log ratio of the QTVN over normalized heart rate variance (QT variability index, or QTVI). RESULTS: A pronounced diurnal variation was seen in both QTVI and QTVN. Both were lowest in the midnight to 6 am time frame and increased throughout the day, peaking at noon to 6 pm, then decreasing 6 pm to midnight. For QTVI, all 4 time points were significantly different (P < .0001). QT variability index correlated with heart rate (r = 0.38, P < .0001) and was significantly higher for those in higher New York Heart Association (NYHA) classes (r = 0.22, P = .0003). Normalized QT variance did not correlate with heart rate or NYHA but correlated negatively with serum potassium (r = -0.22, P = .0002) and manifested the greatest increase during midmorning hours. CONCLUSIONS: Repolarization lability as reflected in QT variability has a pronounced diurnal variation and increases significantly after 6 am, the time of greatest arrhythmic risk. QT variability for 24 hours might improve risk prediction in chronic heart failure patients and should be tested in appropriate trials.

QT Variability Index.

The QT Variability Index (QTVI) is a non-invasive measure of repolarization lability that has been applied to a wide variety of subjects with cardiovascular disease. It is a ratio of normalized QT variability to normalized heart rate variability, and therefore includes an assessment of autonomic nervous system tone. The approach assesses beat-to-beat variability in the duration of the QT and U wave in conventional surface electrocardiographic recordings, as well as determines the heart rate variability (HRV) from the same recording. As opposed to T wave alternans, QTVI assesses variance in repolarization at all frequencies. Nineteen studies have published data on QTVI in healthy individuals, while 20 have evaluated its performance in cohorts with cardiovascular disease. Six studies have assessed the utility of QTVI in predicting VT/VF, cardiac arrest, or cardiovascular death. A prospective study utilizing QTVI to determine therapy allocation has not been performed, and therefore the final determination of the value of the metric awaits definitive exploration.

QT variability index on 24-hour Holter independently predicts mortality in patients with heart failure: analysis of Gruppo Italiano per lo Studio della Sopravvivenza nell'Insufficienza Cardiaca (GISSI-HF) trial.

BACKGROUND: Increased temporal variability of repolarization, as reflected by QT interval variability measured over 10-15 minutes, predicted spontaneous ventricular arrhythmias and death in implantable cardioverter-defibrillator patients in mild to moderate heart failure (HF). OBJECTIVE: The purpose of this study was to test our hypothesis that increased mean QT variability over 24 hours would be associated with increased cardiovascular (CV) mortality in a heterogeneous HF population. METHODS: The Gruppo Italiano per lo Studio della Sopravvivenza nell'Insufficienza Cardiaca-Heart Failure trial prospectively enrolled subjects with HF of any cause. Twenty-four-hour Holter recordings from 268 subjects were analyzed using a template-matching, semiautomatic algorithm to measure QT and heart rate time series in sequential 5-minute epochs over 24 hours. The QT variability index (QTVI) was expressed as the log ratio of the normalized QT variance over normalized heart rate variance. Total and CV mortality were assessed as a function of continuous and dichotomous QTVI (>-0.84) in univariate and multivariable Cox proportional hazards models, adjusting for significant clinical predictors. RESULTS: After a median of 47 months, there were 53 deaths, of which 44 were from CV causes. A significant association with the outcome was found for QTVI both as continuous and dichotomous variables after adjustment for clinical covariates (age >70, New York Heart Association class III-IV, left ventricular ejection fraction, nonsustained ventricular tachycardia, creatinine): QTVI hazard ratio (HR) 4.0 (confidence interval [CI] 1.8-88; P = .008) for total and 4.4 (CI 1.9-10.1; P = .0006) for CV mortality; QTVI >-0.84 HR 2.0 (CI 1.1-3.6; P = .02) for total and 2.1 (CI 1.1-3.8; P = .02) for CV mortality. CONCLUSION: Increased repolarization lability, as reflected in QTVI measured over 24 hours, is associated with increased risk for total and CV mortality in a heterogeneous population with chronic HF.