Safety and Efficacy of Surgical and Percutaneous Cardiac Interventions for Adults With Down Syndrome.

Objective: To assess risks and benefits of cardiac intervention in adults with Down syndrome (DS). Patients and Methods: A retrospective review was conducted using data from a study we published in 2010. Patients aged 18 years or older with DS who underwent cardiac operation or percutaneous intervention from February 2009 through April 2022 (new cohort) were compared with patients in the previous study (January 1969 through November 2007; remote cohort) at Mayo Clinic. Results: In total, 81 adults (43 men; 38 women) with DS underwent 89 cardiac interventions (84 surgical; 5 percutaneous) at a mean age of 33 years. Twenty-six patients presented with complete atrioventricular canal defect (17%) or tetralogy of Fallot (15%). The most common adult procedures were valve interventions: mitral (31%), tricuspid (15%), and pulmonary (12%). Of pulmonary valve interventions in the new cohort, 33% were performed percutaneously. The postoperative mortality rate was low (1% total). The mean time between last operation and death was 16 years. Conclusion: Adults with DS can undergo cardiac operation and percutaneous intervention with low morbidity and mortality risk and good long-term survival.

Role of lipoprotein(a) concentrations in bioprosthetic aortic valve degeneration.

OBJECTIVES: Lipoprotein(a) (Lp(a)) is associated with an increased incidence of native aortic stenosis, which shares similar pathological mechanisms with bioprosthetic aortic valve (bAV) degeneration. However, evidence regarding the role of Lp(a) concentrations in bAV degeneration is lacking. This study aims to evaluate the association between Lp(a) concentrations and bAV degeneration. METHODS: In this retrospective multicentre study, patients who underwent a bAV replacement between 1 January 2010 and 31 December 2020 and had a Lp(a) measurement were included. Echocardiography follow-up was performed to determine the presence of bioprosthetic valve degeneration, which was defined as an increase >10 mm Hg in mean gradient from baseline with concomitant decrease in effective orifice area and Doppler Velocity Index, or new moderate/severe prosthetic regurgitation. Levels of Lp(a) were compared between patients with and without degeneration and Cox regression analysis was performed to investigate the association between Lp(a) levels and bioprosthetic valve degeneration. RESULTS: In total, 210 cases were included (mean age 74.1±9.4 years, 72.4% males). Median time between baseline and follow-up echocardiography was 4.4 (IQR 3.7) years. Bioprostheses degeneration was observed in 33 (15.7%) patients at follow-up. Median serum levels of Lp(a) were significantly higher in patients affected by degeneration versus non-affected cases: 50.0 (IQR 72.0) vs 15.6 (IQR 48.6) mg/dL, p=0.002. In the regression analysis, high Lp(a) levels (≥30 mg/dL) were associated with degeneration both in a univariable analysis (HR 3.6, 95% CI 1.7 to 7.6, p=0.001) and multivariable analysis adjusted by other risk factors for bioprostheses degeneration (HR 4.4, 95% CI 1.9 to 10.4, p=0.001). CONCLUSIONS: High serum Lp(a) is associated with bAV degeneration. Prospective studies are needed to confirm these findings and to investigate whether lowering Lp(a) levels could slow bioprostheses degradation.

Current Management and Future Directions for Pulmonary Arterial Hypertension Associated with Congenital Heart Disease.

Current management of patients with congenital heart disease has increased their survival into adulthood. This is accompanied by potential cardiac complications, including pulmonary hypertension associated with congenital heart disease (PAH-CHD). PAH-CHD constitutes a challenging subgroup of pulmonary hypertension and requires expert management to improve quality of life and prognosis. Novel agents have shown a significant improvement in morbidity and mortality in patients with pulmonary arterial hypertension. However, the long-term effects of these medications on PAH-CHD patients remain somewhat uncertain, necessitating treatment plans largely founded on the clinical experience of the healthcare providers. The aim of this review is to summarize the current evidence and future perspectives regarding treatment strategies for PAH-CHD to help better guide management of this complex disease.

Normal sex and age-specific parameters in a multi-ethnic population: a cardiovascular magnetic resonance study of the Canadian Alliance for Healthy Hearts and Minds cohort.

BACKGROUND: Despite the growing utility of cardiovascular magnetic resonance (CMR) for cardiac morphology and function, sex and age-specific normal reference values derived from large, multi-ethnic data sets are lacking. Furthermore, most available studies use a simplified tracing methodology. Using a large cohort of participants without history of cardiovascular disease (CVD) or risk factors from the Canadian Alliance for Healthy Heart and Minds, we sought to establish a robust set of reference values for ventricular and atrial parameters using an anatomically correct contouring method, and to determine the influence of age and sex on ventricular parameters. METHODS AND RESULTS: Participants (n = 3206, 65% females; age 55.2 ± 8.4 years for females and 55.1 ± 8.8 years for men) underwent CMR using standard methods for quantitative measurements of cardiac parameters. Normal ventricular and atrial reference values are provided: (1) for males and females, (2) stratified by four age categories, and (3) for different races/ethnicities. Values are reported as absolute, indexed to body surface area, or height. Ventricular volumes and mass were significantly larger for males than females (p < 0.001). Ventricular ejection fraction was significantly diminished in males as compared to females (p < 0.001). Indexed left ventricular (LV) end-systolic, end-diastolic volumes, mass and right ventricular (RV) parameters significantly decreased as age increased for both sexes (p < 0.001). For females, but not men, mean LV and RVEF significantly increased with age (p < 0.001). CONCLUSION: Using anatomically correct contouring methodology, we provide accurate sex and age-specific normal reference values for CMR parameters derived from the largest, multi-ethnic population free of CVD to date. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02220582. Registered 20 August 2014-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02220582 .

The impact of reporting magnetic resonance imaging incidental findings in the Canadian alliance for healthy hearts and minds cohort.

BACKGROUND: In the Canadian Alliance for Healthy Hearts and Minds (CAHHM) cohort, participants underwent magnetic resonance imaging (MRI) of the brain, heart, and abdomen, that generated incidental findings (IFs). The approach to managing these unexpected results remain a complex issue. Our objectives were to describe the CAHHM policy for the management of IFs, to understand the impact of disclosing IFs to healthy research participants, and to reflect on the ethical obligations of researchers in future MRI studies. METHODS: Between 2013 and 2019, 8252 participants (mean age 58 ± 9 years, 54% women) were recruited with a follow-up questionnaire administered to 909 participants (40% response rate) at 1-year. The CAHHM policy followed a restricted approach, whereby routine feedback on IFs was not provided. Only IFs of severe structural abnormalities were reported. RESULTS: Severe structural abnormalities occurred in 8.3% (95% confidence interval 7.7-8.9%) of participants, with the highest proportions found in the brain (4.2%) and abdomen (3.1%). The majority of participants (97%) informed of an IF reported no change in quality of life, with 3% of participants reporting that the knowledge of an IF negatively impacted their quality of life. Furthermore, 50% reported increased stress in learning about an IF, and in 95%, the discovery of an IF did not adversely impact his/her life insurance policy. Most participants (90%) would enrol in the study again and perceived the MRI scan to be beneficial, regardless of whether they were informed of IFs. While the implications of a restricted approach to IF management was perceived to be mostly positive, a degree of diagnostic misconception was present amongst participants, indicating the importance of a more thorough consent process to support participant autonomy. CONCLUSION: The management of IFs from research MRI scans remain a challenging issue, as participants may experience stress and a reduced quality of life when IFs are disclosed. The restricted approach to IF management in CAHHM demonstrated a fair fulfillment of the overarching ethical principles of respect for autonomy, concern for wellbeing, and justice. The approach outlined in the CAHHM policy may serve as a framework for future research studies. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT02220582 .

Comparison of echocardiographic parameters with cardiac magnetic resonance imaging in the assessment of right ventricular function.

INTRODUCTION: The right ventricle (RV) strain measured by speckle tracking (RVS) is an echocardiographic parameter used to assess RV function. We compared RVS to RV fractional area change (FAC%), tricuspid annular plane systolic excursion (TAPSE) and Doppler tissue imaging-derived peak systolic velocity (S') in the assessment of right ventricular (RV) systolic function measured using cardiac magnetic resonance imaging (MRI). METHODS: We enrolled consecutive patients who underwent cardiac MRI between Jan 2012 and Dec 2017 and a transthoracic echocardiogram (TTE) within 1 month of the MRI with no interval event. Baseline clinical characteristics and MRI parameters were extracted from chart review. Echocardiographic parameters were measured prospectively. TTE parameters including RVS, TAPSE, S', and FAC% were tested for accuracy to identify impaired RV EF (EF < 45% & <30%) using receiver operator curves. RESULTS: The study cohort included 500 patients with mean age 55 years ± 18 and peak tricuspid regurgitation velocity 2.7 ± 1.4 m/s. The area under ROC for RVS was 0.69 (95% CI 0.63-0.75) and 0.78 (95% CI 0.70-0.88) to predict RVEF < 45% & RVEF < 30%, respectively. The RV FAC% had second highest accuracy of predicting RVEF among all the TTE parameters tested in study. CONCLUSION: Right ventricular strain is the most accurate echocardiographic method to detect impaired right ventricular systolic function when using MRI as the gold standard.

Management of adults with coarctation of aorta.

Coarctation of the aorta (CoA) is a relatively common congenital cardiac defect often causing few symptoms and therefore can be challenging to diagnose. The hallmark finding on physical examination is upper extremity hypertension, and for this reason, CoA should be considered in any young hypertensive patient, justifying measurement of lower extremity blood pressure at least once in these individuals. The presence of a significant pressure gradient between the arms and legs is highly suggestive of the diagnosis. Early diagnosis and treatment are important as long-term data consistently demonstrate that patients with CoA have a reduced life expectancy and increased risk of cardiovascular complications. Surgical repair has traditionally been the mainstay of therapy for correction, although advances in endovascular technology with covered stents or stent grafts permit nonsurgical approaches for the management of older children and adults with native CoA and complications. Persistent hypertension and vascular dysfunction can lead to an increased risk of coronary disease, which, remains the greatest cause of long-term mortality. Thus, blood pressure control and periodic reassessment with transthoracic echocardiography and three-dimensional imaging (computed tomography or cardiac magnetic resonance) for should be performed regularly as cardiovascular complications may occur decades after the intervention.

Cardiovascular risk scoring and magnetic resonance imaging detected subclinical cerebrovascular disease.

AIMS: Cardiovascular risk factors are used for risk stratification in primary prevention. We sought to determine if simple cardiac risk scores are associated with magnetic resonance imaging (MRI)-detected subclinical cerebrovascular disease including carotid wall volume (CWV), carotid intraplaque haemorrhage (IPH), and silent brain infarction (SBI). METHODS AND RESULTS: A total of 7594 adults with no history of cardiovascular disease (CVD) underwent risk factor assessment and a non-contrast enhanced MRI of the carotid arteries and brain using a standardized protocol in a population-based cohort recruited between 2014 and 2018. The non-lab-based INTERHEART risk score (IHRS) was calculated in all participants; the Framingham Risk Score was calculated in a subset who provided blood samples (n = 3889). The association between these risk scores and MRI measures of CWV, carotid IPH, and SBI was determined. The mean age of the cohort was 58 (8.9) years, 55% were women. Each 5-point increase (∼1 SD) in the IHRS was associated with a 9 mm3 increase in CWV, adjusted for sex (P < 0.0001), a 23% increase in IPH [95% confidence interval (CI) 9-38%], and a 32% (95% CI 20-45%) increase in SBI. These associations were consistent for lacunar and non-lacunar brain infarction. The Framingham Risk Score was also significantly associated with CWV, IPH, and SBI. CWV was additive and independent to the risk scores in its association with IPH and SBI. CONCLUSION: Simple cardiovascular risk scores are significantly associated with the presence of MRI-detected subclinical cerebrovascular disease, including CWV, IPH, and SBI in an adult population without known clinical CVD.

Variability in the Echocardiographic Evaluation of the Systemic Right Ventricle.

BACKGROUND: Echocardiographic evaluation of the systemic right ventricle (sRV) remains challenging in patients with transposition of the great arteries (TGA) corrected by an atrial switch (AS) and with congenitally corrected TGA (ccTGA). The aim of this study was to determine the interobserver and intraobserver variability of echocardiographic parameters for sRV size and systolic function. METHODS: Six independent observers retrospectively interpreted 44 previously acquired echocardiograms (25 patients with TGA/AS and 19 patients with ccTGA). Quantitative parameters included inlet and longitudinal diameters, systolic and diastolic areas, fractional area change (FAC), and wall thickness. sRV dilatation and systolic function were qualitatively graded as normal, mild, moderate, or severe. sRV hypertrophy was graded as present or absent. Intraclass correlation coefficients (ICCs) and Kappa statistics were computed to assess interobserver variability. Images from 10 patients (5 TGA/AS and 5 ccTGA) were reinterpreted at a 1-month interval, and ICC and Kendall tau b statistics were computed to assess intraobserver variability. RESULTS: Interobserver and intraobserver agreement were good to excellent for sRV diameters, areas and FAC (ICC, 0.49-0.97), except for the sRV wall thickness (ICC < 0) and the FAC for 1 observer. Interobserver agreement was poor for the qualitative assessment of sRV size and systolic function (Kappa < 0.25), but with a good to excellent intraobserver agreement. CONCLUSIONS: These findings suggest that overall appreciation of sRV size and systolic function relies on variable interpretation of measurements by observers. Readers experienced in CHD and with clear thresholds for quantitative parameters, along with a validated algorithm, are required to guide the evaluation of sRV.

Myocardial Partition Coefficient of Gadolinium: A Pilot Study in Patients With Acute Myocarditis, Chronic Myocardial Infarction, and in Healthy Volunteers.

BACKGROUND: The tissue-blood partition coefficient (PC) of gadolinium, derived from T1 measurements, reflects myocardial connective tissue fraction and tissue injury, increasing in proportion with edema or fibrosis. We determined the myocardial PC of gadolinium in patients with acute myocarditis, chronic myocardial infarction (MI), and healthy volunteers. We hypothesized that the characteristics of the injured myocardium in patients with MI and myocarditis may differ and that the PC will be higher in chronically injured myocardium (MI) compared with acutely injured myocardium (myocarditis). METHODS: We performed late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging and T1 mapping before and after administration of gadolinium (0.1 mmol/kg Gd-BOPTA) at 3 Tesla in 10 healthy volunteers (47.1 ± 12.4 years), 18 patients with chronic MI (62.5 ± 8.1 years), and 16 patients with acute myocarditis (42.5 ± 13.9 years). RESULTS: In patients with chronic MI and focal scar by LGE, the whole left ventricular myocardial PC (0.45 ± 0.05) was higher compared with patients with MI without focal scar (0.39 ± 0.03, P = 0.02) but not significantly different from whole myocardial PC in volunteers (0.40 ± 0.05) or patients with myocarditis (0.41 ± 0.05). The PC in myocarditis scars was lower than in chronic MI scars (0.60 ± 0.12 vs 0.77 ± 0.16, P = 0.016). The relationships of PC and scar burden, expressed as % LGE, were similar and significant for the 2 groups (P = 0.042). CONCLUSION: The tissue-blood partition coefficient of Gd-BOPTA is elevated in areas of acute and chronic myocardial injury and may serve as a marker for disease activity and density of scars, which was found to be higher in chronic MI than in acute myocarditis.

Transvenous Lead Extraction in Adults With Congenital Heart Disease: Insights From a 20-Year Single-Center Experience.

BACKGROUND: Safety and feasibility data on transvenous lead extraction (TLE) in the challenging population of adults with congenital heart disease (A-CHD) are limited. Herein, we report the results of TLE in A-CHD during a 20-year period. METHODS AND RESULTS: All consecutive TLE procedures in A-CHD were included in a monocentric prospective registry from 1996. A total of 121 leads were extracted in 49 A-CHD (median age, 38 years; 51% men) during 71 TLE procedures. Twenty-four (49%) patients had transposition of the great arteries. Main indications for extraction were infection in 34 (48%) and lead failure in 22 (31%). A laser sheath was required for 56 (46%) leads and a femoral approach for 10 (8%). Complete TLE was achieved for 111 leads (92%). In multivariable analysis, lead duration (odds ratio, 1.02; 95% confidence interval, 1.00-1.04; P<0.01) and number of previous cardiac surgeries (odds ratio, 2.65; 95% confidence interval, 1.52-4.67; P<0.01) were predictive of TLE failure. No perioperative death or pericardial effusion was observed. Subpulmonary atrioventricular valve regurgitation increased in 8 patients (5 with transposition of the great arteries) and was independently associated with an implantable cardioverter defibrillator lead (odds ratio, 9.69; 95% confidence interval, 1.31-71.64; P=0.03) and valvular vegetation (odds ratio, 7.29; 95% confidence interval, 1.32-40.51; P=0.02). After a median of 54 (19-134) months of follow-up after the first TLE, 3 deaths occurred independently from lead management. CONCLUSIONS: Despite complex anatomic issues, TLE can be achieved successfully in most A-CHD using advanced extraction techniques. Subpulmonary atrioventricular valve regurgitation is a prevalent complication, particularly in patients with transposition of the great arteries.

Late Onset Postcapillary Pulmonary Hypertension in Patients With Transposition of the Great Arteries and Mustard or Senning Baffles.

BACKGROUND: There is a paucity of data regarding late-onset pulmonary hypertension (PH) in patients with transposition of the great arteries and atrial switch surgery. METHODS AND RESULTS: A retrospective cohort study was conducted on 140 adults with transposition of the great arteries and atrial switch surgery, age 37.3±7.8, 37.1% female, in order to assess the prevalence and characteristics of late-onset PH and explore associated factors. Patients were followed for a median of 32.3 years after atrial switch surgery and 10.0 years after their first referral visit. PH was detected in 18 of 33 (54.5%) patients who had invasive hemodynamic studies. Average age at diagnosis of PH was 33.9±8.1 years. PH was postcapillary in all, with a mean pulmonary artery pressure of 36±12 mm Hg and mean pulmonary capillary wedge pressure of 28±8 mm Hg. PH was diagnosed in 13 of 17 (76.5%) patients who had cardiac catheterization for heart failure or decreased exercise tolerance. In multivariable analyses, systemic hypertension (odds ratio 9.4, 95% confidence interval 2.2-39.4, P=0.002) and heart failure or New York Heart Association class III or IV symptoms (odds ratio 49.8, 95% confidence interval 8.6-289.0, P<0.001) were independently associated with PH. Patients with PH were more likely to develop cardiovascular comorbidities including atrial (P=0.001) and ventricular (P=0.008) arrhythmias, require hospitalizations for heart failure (P<0.001), and undergo tricuspid valve surgery (P<0.001). Mortality was significantly higher in patients with PH (hazard ratio 9.4, 95% confidence interval 2.1-43.0], P<0.001). CONCLUSIONS: Late-onset postcapillary PH is highly prevalent in adults with transposition of the great arteries and atrial switch surgery and is associated with an adverse prognosis.

Shone Complex: An Under-recognized Congenital Heart Disease With Substantial Morbidity in Adulthood.

BACKGROUND: Shone complex consists of a constellation of left-sided, usually obstructive, cardiac lesions, including supravalvar mitral ring, parachute mitral valve, subaortic stenosis, and aortic coarctation. Incomplete Shone complex consists of a mitral valve anomaly associated with lesions involving the subaortic region, aortic valve, or thoracic aorta. There is a paucity of data regarding long-term outcomes in adults with Shone complex. METHODS: We reviewed records of adults with complete or incomplete Shone complex followed at the Montreal Heart Institute between 1982 and 2014. RESULTS: Among 4189 adults with congenital heart disease, 28 (0.67%) patients (mean age, 35 ± 11 years; 50% women) had complete or incomplete Shone complex and were followed for a median of 8 years. Only 39% were previously diagnosed as having Shone complex. The most common defects were congenital mitral stenosis (93%), aortic coarctation (75%), and bicuspid aortic valve (71%). Heart transplantation was required in 2 patients (7.1%) at age 22 and 28 years, respectively. Overall, 48% had cardiovascular hospitalizations during adulthood, predominantly for arrhythmias or heart failure. Freedom from cardiovascular intervention was 55%, 18%, and 8% at 10, 20, and 30 years of age, respectively. Although aortic coarctation was the most common indication for initial intervention (61%), adult interventions occurred predominantly for aortic valve/left ventricular outflow tract (60%) and mitral valve (33%) lesions. CONCLUSIONS: Shone complex is an under-recognized entity associated with relatively low mortality in adulthood but substantial morbidity related to arrhythmias, heart failure, and interventions. Increased awareness of this condition and associated complications may allow for more tailored follow-up.

Thromboprophylaxis for atrial arrhythmias in congenital heart disease: A multicenter study.

BACKGROUND: There is a paucity of data to guide decisions regarding thromboprophylaxis for atrial arrhythmias in congenital heart disease. METHODS: A retrospective multicenter cohort study enrolled patients with documented sustained atrial arrhythmias and congenital heart disease from 12 North American centers to quantify thromboembolic and bleeding rates associated with antiplatelet and anticoagulation therapy, and explore associated factors. A blinded committee adjudicated all qualifying arrhythmias and outcomes. RESULTS: A total of 482 patients, 45.2% female, age 32.0±18.0years, were followed for 11.3±9.4years since the qualifying arrhythmia. Antiplatelet therapy was administered to 37.8%, anticoagulation to 54.4%, and neither to 7.9%. Congenital heart disease complexity was simple, moderate, and severe in 18.5%, 34.4%, and 47.1%, respectively. Freedom from thromboembolic events was 84.7±2.7% at 15years, with no difference between anticoagulation versus antiplatelet therapy (P=0.97). Congenital heart disease complexity was independently associated with thromboembolic events, with rates of 0.00%, 0.93%, and 1.95%/year in those with simple, moderate, and severe forms (P<0.001). CHADS2 and CHA2DS2-VASc scores were not predictive of thromboembolic risk. Annualized bleeding rates with antiplatelet and anticoagulation therapy were 0.66% and 1.82% (P=0.039). In multivariable analyses, anticoagulation [hazard ratio (HR) 4.76, 95% CI (1.05-21.58), P=0.043] and HAS-BLED score [HR 3.15, 95% CI (1.02, 9.78), P=0.047] were independently associated with major bleeds. CONCLUSION: Current management of atrial arrhythmias in congenital heart disease is associated with a modest rate of thromboembolic events, which is predicted by disease complexity but not CHADS2/CHA2DS2-VASc scores. HAS-BLED score is applicable to the congenital population in predicting major bleeds.

Rationale, design, and methods for Canadian alliance for healthy hearts and minds cohort study (CAHHM) - a Pan Canadian cohort study.

BACKGROUND: The Canadian Alliance for Healthy Hearts and Minds (CAHHM) is a pan-Canadian, prospective, multi-ethnic cohort study being conducted in Canada. The overarching objective of the CAHHM is to understand the association of socio-environmental and contextual factors (such as societal structure, activity, nutrition, social and tobacco environments, and access to health services) with cardiovascular risk factors, subclinical vascular disease, and cardiovascular and other chronic disease outcomes. METHODS/DESIGN: Participants between 35 and 69 years of age are being recruited from existing cohorts and a new First Nations Cohort to undergo a detailed assessment of health behaviours (including diet and physical activity), cognitive function, assessment of their local home and workplace environments, and their health services access and utilization. Physical measures including weight, height, waist/hip circumference, body fat percentage, and blood pressure are collected. In addition, eligible participants undergo magnetic resonance imaging (MRI) of the brain, heart, carotid artery and abdomen to detect early subclinical vascular disease and ectopic fat deposition. DISCUSSION: CAHHM is a prospective cohort study designed to investigate the impact of community level factors, individual health behaviours, and access to health services, on cognitive function, subclinical vascular disease, fat distribution, and the development of chronic diseases among adults living in Canada.

The impact of exercise on ventricular arrhythmias in adults with tetralogy of Fallot.

BACKGROUND: Sudden death of presumed arrhythmic etiology is the leading cause of mortality in adults with tetralogy of Fallot. OBJECTIVES: To assess the impact of exercise on ventricular arrhythmias in adults with tetralogy of Fallot. METHODS: Adults with repaired tetralogy of Fallot were randomized in a 2:1 ratio to an open-label trial of standard care versus 12weeks of supervised combined aerobic/resistance training with continuous Holter monitoring. Proportion of premature ventricular complexes (PVC) and runs of non-sustained ventricular tachycardia (NSVT) were assessed by mixed and Poisson regression models with generalized estimating equations for repeated measures. RESULTS: A total of 152 Holters were performed in 17 patients, median age 35 (interquartile range [IQR] 28, 42) years, 65% male, 13 of whom were randomized to exercise training. Baseline characteristics were similar between groups. Exercise training resulted in significant increases in peak oxygen uptake (11±19%, p=0.028), metabolic equivalents (11±18%, p=0.027), and exercise duration (8±10%, p=0.009) compared to no changes in controls. Frequent (≥30 per hour) PVCs were present in 46% of patients, couplets in 62%, and 3 to 7 beat runs of NSVT in 31%. The median proportion of PVCs was 1.93‰ (IQR 0.41, 5.89) at baseline and 1.45‰ (IQR 0.08, 2.76) during the initial exercise session (p=0.722), and remained stable over time (ß coefficient=-0.031, p=0.408). Runs of NSVT decreased significantly over time (ß coefficient=-0.032, p=0.018). CONCLUSION: In adults with repaired tetralogy of Fallot, exercise training is safe, improves exercise capacity, and appears to confer a beneficial effect on ventricular arrhythmias.

Breathing maneuvers as a coronary vasodilator for myocardial perfusion imaging.

PURPOSE: A combined breathing maneuver of hyperventilation, followed by a long voluntary breathhold leads to coronary vasodilation. We investigated the impact of breathing maneuvers on MR first-pass cardiac perfusion imaging and its potential clinical utility. MATERIALS AND METHODS: We studied 24 healthy volunteers (37 ± 12 years; 62.5% men) on a clinical 3 Tesla MRI system and performed first-pass perfusion MR at rest, during a short breathhold (S-HVBH) following 60 s of hyperventilation, and at the end of a long breathhold (L-HVBH) following the hyperventilation, performed in random order. A blinded reader analyzed signal intensity upslope, upslope index, and time between 20 and 80% of maximal signal. RESULTS: All volunteers tolerated the breathing maneuvers well and completed the study protocol. The upslope of the signal-intensity-over-time curve was increased during S-HVBH (1.86 ± 0.70 units/s, P < 0.05) and at the end of L-LVBH (1.77 ± 0.82 units/s), when compared with baseline results (1.34 ± 0.58 units/s). Corrected for the arterial input, the upslope was higher at the end of the L-HVBH (0.095 ± 0.019 units/s versus 0.077 ± 0.016 units/s at rest, P < 0.01) as was the myocardial perfusion reserve index (1.25 ± 0.22 versus 1.09 ± 0.17; P < 0.001). In a multiple regression model, only gender, rate-pressure product, and breathhold time were independently and significantly related to the upslope (R = 0.771; P < 0.001). CONCLUSION: In conclusion, a voluntary long breathhold after hyperventilation leads to an increase of the myocardial perfusion reserve index. This may impact findings from current practice of first-pass perfusion imaging. The clinical utility of breathing maneuvers as a vasodilatory stimulus for first-pass perfusion imaging may warrant further research. J. MAGN. RESON. IMAGING 2016;44:947-955.

Risks and Benefits of Exercise Training in Adults With Congenital Heart Disease.

Exercise capacity in adults with various forms of congenital heart disease is substantially lower than that of the general population. Although the underlying congenital heart defect, and its sequelae, certainly contribute to observed exercise limitations, there is evidence suggesting that deconditioning and a sedentary lifestyle are important implicated factors. The prevalence of acquired cardiovascular comorbidities is on the increase in the aging population with congenital heart disease, such that obesity and a sedentary lifestyle confer increased risk. Health fears and misconceptions are common barriers to regular physical activity in adults with congenital heart disease, despite evidence linking lower functional capacity to poor outcomes, and data supporting the safety and efficacy of exercise in bestowing numerous physical and psychosocial rewards. With few exceptions, adults with congenital heart disease should be counselled to exercise regularly. In this contemporary review, we provide a practical approach to assessing adults with congenital heart disease before exercise training. We examine available evidence supporting the safety and benefits of exercise training. Risks associated with exercise training in adults with congenital heart disease are discussed, particularly with regard to sudden cardiac death. Finally, recommendations for exercise training are provided, with consideration for the type of congenital heart disease, the nature (ie, static vs dynamic) and intensity (ie, low, medium, high) of the physical activity, and associated factors such as systemic ventricular dysfunction and residual defects. Further research is required to determine optimal exercise regimens and to identify effective strategies to implement exercise training as a key determinant of healthy living.

Multimodality Noninvasive Imaging of Thoracic Aortic Aneurysms: Time to Standardize?

Aortic imaging is an essential part of a surveillance program for patients with a confirmed or suspected aortopathy because aortic size is crucial for predicting the risk of death, aortic rupture, or aortic dissection. Noninvasive aortic imaging relies on transthoracic and transesophageal echocardiography, cardiovascular magnetic resonance and computed tomography (CT) imaging. Echocardiography and cardiovascular magnetic resonance offer comprehensive anatomical and functional evaluation of the heart, aortic valve, and aorta, and CT is more limited to anatomical data. However, CT is fast, available, and less operator-dependent. There is general consensus that the aorta should be measured at reproducible anatomical landmarks on electrocardiogram-gated images, perpendicular to the blood flow and using multiplanar reconstruction if possible. The method of measurement must be included in the clinical report. Normal aortic size depends on age, sex, and body size. Serial measurements should use identical methods. There is controversy about the inclusion of the aortic wall in the vessel diameter and the trigger time in the cardiac cycle for measurement, although diastole is more reproducible. The best method to measure the diameter of the sinuses of Valsalva remains unclear. Imagers and clinicians should pay close attention to the aorta measurement techniques and weigh the clinical implications of modification of their institutional protocols.

Magnetic resonance imaging of hypertrophic cardiomyopathy: beyond left ventricular wall thickness.

During the past decade, cardiac magnetic resonance has gained increasing popularity in the diagnosis of hypertrophic cardiomyopathy because of its greater accuracy and better characterization of cardiac morphology compared with other imaging modalities. In this pictorial essay, a global clinical portrait of hypertrophic cardiomyopathy will be drawn. The various radiologic findings associated with each variant of hypertrophic cardiomyopathy, and the clinical edge offered by cardiac magnetic resonance will be discussed.