Beneficial Effects of Exercise on Hypertension-Induced Cardiac Hypertrophy in Adolescents and Young Adults.

PURPOSE OF REVIEW: Hypertension-induced cardiac hypertrophy is widely known as a major risk factor for increased cardiovascular morbidity and mortality. Although exercise is proven to exert overall beneficial effects on hypertension and hypertension-induced cardiac hypertrophy, there are some concerns among providers about potential adverse effects induced by intense exercise, especially in hypertensive athletes. We will overview the underlying mechanisms of physiological and pathological hypertrophy and delineate the beneficial effects of exercise in young people with hypertension and consequent hypertrophy. RECENT FINDINGS: Multiple studies have demonstrated that exercise training, both endurance and resistance types, reduces blood pressure and ameliorates hypertrophy in hypertensives, but certain precautions are required for hypertensive athletes when allowing competitive sports: Elevated blood pressure should be controlled before allowing them to participate in high-intensity exercise. Non-vigorous and recreational exercise are always recommended to promote cardiovascular health. Exercise-induced cardiac adaptation is a benign and favorable response that reverses or attenuates pathological cardiovascular remodeling induced by persistent hypertension. Exercise is the most effective nonpharmacological treatment for hypertensive individuals. Distinction between recreational-level exercise and competitive sports should be recognized by medical providers when allowing sports participation for adolescents and young adults.

Correlation of Echocardiogram and Exercise Test Data in Children with Aortic Stenosis.

Previous pediatric exercise test criteria for aortic stenosis severity were based on cardiac catheterization assessment, whereas current criteria are based on echocardiographic valve gradients. We sought to correlate exercise test criteria with echocardiographic assessment of severity. We report 65 studies, 51 patients (mean age of 13 ± 4 years; 75% males), with aortic stenosis (AS) who had a maximal exercise test between 2005 and 2016. We defined three groups based on resting mean Doppler gradient across their aortic valve: severe AS (n = 10; gradient of ≥ 40 mmHg), moderate AS (n = 20; gradient 25-39 mmHg), and mild AS (n = 35; gradient ≤ 24 mmHg). We studied symptoms (chest pain) during exercise, resting electrocardiogram changes (left ventricular hypertrophy [LVH]), complex arrhythmias during exercise, change in exercise systolic blood pressure (SBP; delta SBP = peak SBP-resting SBP), exercise duration, work, echocardiogram parameters (LVH), and ST-T wave changes with exercise. Additionally, we compared work and delta SBP during exercise with 117 control males and females without heart disease. Severe AS patients have statistically significant differences when compared with mild AS in ST-T wave depression during exercise, LVH on resting electrocardiogram, and echocardiogram. There was a significant difference in delta SBP between severe AS and normal controls (delta SBP 21.6 vs. 46.2 mmHg), and between moderate AS and normal controls (delta SBP 32 vs. 46.2 mmHg). There were no significant complications during maximal exercise testing. Children with echocardiographic severe and moderate AS have exercise testing abnormalities. Exercise test criteria for severity of AS were validated for echocardiographic criteria for AS severity.

Standardization of a Continuous Ramp Ergometer Protocol for Clinical Exercise Testing in Children.

Developing a standardized protocol for pediatric exercise laboratories is challenging. Our objective was to report normal pediatric values for a continuous non-steady state cycle ergometer ramp protocol to achieve 8-10 min of exercise based on sex and weight. One hundred seventeen patients (117) [mean age 13 ± 2.8 years, range 7-18 years (51% male)] referred for chest pain with normal cardiac evaluation underwent cardiopulmonary testing on a cycle ergometer. Patients entered one of the four continuous ramp protocols (10, 15, 20, and 25 W/min ramp) to achieve an expected peak workload of 3 W/kg at an increase of 0.3 to 0.35 W/kg/min. Exercise test outcomes measured included duration, peak heart rate, work, respiratory exchange ratio, peak oxygen consumption, peak blood pressure, and ventilatory anaerobic threshold. An exercise duration of 8-10 min was achieved in a majority of the study population; however, interactions with age (older, longer duration) and sex (males, longer duration) were present. Using our algorithm (0.3-0.35 W/kg × weight), we demonstrated four non-steady state ramp bike ergometer protocols (10, 15, 20, and 25 W/min) that can be applied to males and females of different ages and weights to achieve an exercise duration of 8-10 min.

Identifying Subclinical Coronary Abnormalities and Silent Myocardial Ischemia After Arterial Switch Operation.

The incidence of late coronary complications is reported around 8% after arterial switch operation (ASO) for d-transposition of the great arteries, but the affected patients are usually asymptomatic. Exercise stress test (EST) and myocardial perfusion imaging (MPI) are common non-invasive modalities to screen for silent myocardial ischemia, but their diagnostic reliability in children after ASO is unclear. We retrospectively reviewed asymptomatic patients following ASO with EST, MPI, and coronary imaging studies (CIS) and examined the reliability of each test in identifying abnormal coronary lesions responsible for myocardial ischemia. Thirty-seven asymptomatic patients (24 males; ages 12.7 ± 3.7 years) had EST, in which 27 and 33 patients also underwent MPI and CIS, respectively. Exercise capacity was comparable to the age- and sex-matched 37 controls. In seven patients with angiographically proven moderate to severe coronary abnormalities, only two patients had positive EST and/or MPI, and five patients were negative including one patient who later developed exercise-induced cardiac arrest due to severe proximal left coronary artery stenosis. Two patients with positive EST or MPI showed no corresponding coronary abnormalities by CIS. Occurrence of acquired late coronary abnormalities did not correlate with the original coronary anatomy or initial surgical procedures. There is no single reliable method to identify the risk of myocardial ischemia after ASO. Although CIS are regarded as a gold standard, multidisciplinary studies are essential to risk-stratify the potential life-threatening coronary lesions after ASO in children.

Coronary artery problems late after arterial switch operation for transposition of the great arteries.

BACKGROUND: The incidence of late coronary artery abnormalities after arterial switch operation (ASO) for d-loop transposition of the great arteries may be underestimated. METHODS AND RESULTS: We retrospectively reviewed coronary artery morphology in 40 of 97 patients who survived the first year after ASO. Seven asymptomatic patients developed significant late coronary artery abnormalities. One patient died suddenly at home with severe left coronary artery (LCA) ostial stenosis at age 3.8 years. The second patient collapsed during exercise at age 9.6 years due to ventricular fibrillation and severe LCA ostial stenosis despite prior negative exercise stress test (EST) and myocardial perfusion imaging (MPI). The third patient was found to have moderate ostial stenosis of the LCA with negative EST and MPI. The fourth patient with exercise-induced ST-T depression and myocardial perfusion defect was shown to have complete LCA occlusion with collateral vessel formation. Three other patients had complete proximal obliteration of either of the coronary arteries with collateral supply. An additional 4 asymptomatic patients had trivial-mild narrowing of the LCA on routine selective coronary angiogram. CONCLUSIONS: Incidence of late coronary stenosis or occlusion was not infrequent after ASO (11.3%) and presented usually without preceding symptoms and often after negative non-invasive screening. We advocate routine coronary imaging in all patients after ASO before they participate in competitive sports.

Implementing Entrustable Professional Activities in Pediatric Fellowships: Facilitating the Process.

BACKGROUND AND OBJECTIVES: Entrustable professional activities (EPAs) will be used for initial certification by the American Board of Pediatrics by 2028. Less than half of pediatric fellowships currently use EPAs for assessment, yet all will need to adopt them. Our objectives were to identify facilitators and barriers to the implementation of EPAs to assess pediatric fellows and to determine fellowship program directors' (FPD) perceptions of EPAs and Milestones. METHODS: We conducted a survey of FPDs from 15 pediatric subspecialties. EPA users were asked about their implementation of EPAs, barriers encountered, and perceptions of EPAs. Nonusers were queried about deterrents to using EPAs. Both groups were asked about potential facilitators of implementation and their perceptions of Milestones. RESULTS: The response rate was 65% (575/883). Of these, 344 (59.8%) were EPA users and 231 (40.2%) were nonusers. Both groups indicated work burden as a barrier to implementation. Nonusers reported more barriers than users (mean [SD]: 7 [3.8] vs 5.8 [3.4], P < .001). Both groups identified training materials and premade assessment forms as facilitators to implementation. Users felt that EPAs were easier to understand than Milestones (89%) and better reflected what it meant to be a practicing subspecialty physician (90%). In contrast, nonusers felt that Milestones were easy to understand (57%) and reflected what it meant to be a practicing subspecialist (58%). CONCLUSIONS: Implementing EPA-based assessment will require a substantial investment by FPDs, facilitated by guidance and easily accessible resources provided by multiple organizations. Perceived barriers to be addressed include FPD time constraints, a need for additional assessment tools, and outcomes data.

Trisomy 18 in a 20-year-old woman.

A 20-year-old female with trisomy 18 is described. Survival past infancy is rare in this disorder. Little is known concerning the factors that contribute to prolonged survival with this syndrome. This case provides an opportunity to review the management of older children and young adults with trisomy 18.