Effects of steroids and angiotensin converting enzyme inhibition on circumferential strain in boys with Duchenne muscular dystrophy: a cross-sectional and longitudinal study utilizing cardiovascular magnetic resonance

Prophylactic use of cardiac medications for delay of left ventricular dysfunction in Duchenne muscular dystrophy

BACKGROUND

Epidemiological support for prophylactic treatment of left ventricular dysfunction (LVD) in Duchenne muscular dystrophy is limited. We used retrospective, population-based surveillance data from the Muscular Dystrophy Surveillance, Tracking and Research Network to evaluate whether prophylaxis delays LVD onset.

METHODS

We analyzed 455 males born during 1982-2009. Age at first abnormal echocardiogram (ejection fraction <55% or shortening fraction <28%) determined LVD onset. Prophylaxis was defined as cardiac medication use at least 1 year prior to LVD. Corticosteroid use was also coded. Kaplan-Meier curve estimation and Cox Proportional Hazard modeling with time-varying covariates describe associations.

RESULTS

LVD was identified among 40.7%; average onset age was 14.2 years. Prophylaxis was identified for 20.2% and corticosteroids for 57.4%. Prophylaxis showed delayed LVD onset (p < .001) and lower hazard of dysfunction (adjusted hazard ratio [aHR] = 0.39, 95%CL = 0.22, 0.65) compared to untreated. Compared to no treatment, continuous corticosteroids only (aHR = 1.01, 95%CL = 0.66, 1.53) and prophylaxis only (aHR = 0.67, 95%CL = 0.25, 1.50) were not cardioprotective, but prophylaxis plus continuous corticosteroids were associated with lower hazard of dysfunction (aHR = 0.37, 95%CL = 0.15, 0.80).

CONCLUSIONS

Proactive cardiac treatment and monitoring are critical aspects of managing Duchenne muscular dystrophy. Consistent with clinical care guidelines, this study supports clinical benefit from cardiac medications initiated prior to documented LVD and suggests further benefit when combined with corticosteroids.

Cardiac magnetic resonance in patients with muscular dystrophies

Muscular dystrophies are inherited disorders sharing similar clinical features and dystrophic changes on muscle biopsy. Duchenne muscular dystrophy is the most common inherited muscle disease of childhood, and Becker muscular dystrophy is a milder allelic variant with a slightly lower prevalence. Myotonic dystrophy is the most frequent form in adults. Cardiac magnetic resonance is the gold standard technique for the quantification of cardiac chamber volumes and function, and also enables a characterisation of myocardial tissue. Most cardiac magnetic resonance studies in the setting of muscular dystrophy were carried out at single centres, evaluated small numbers of patients and used widely heterogeneous protocols. Even more importantly, those studies analysed more or less extensively the patterns of cardiac involvement, but usually did not try to establish the added value of cardiac magnetic resonance to standard echocardiography, the evolution of cardiac disease over time and the prognostic significance of cardiac magnetic resonance findings. As a result, the large and heterogeneous amount of information on cardiac involvement in muscular dystrophies cannot easily be translated into recommendations on the optimal use of cardiac magnetic resonance. In this review, whose targets are cardiologists and neurologists who manage patients with muscular dystrophy, we try to summarise cardiac magnetic resonance findings in patients with muscular dystrophy, and the results of studies evaluating the role of cardiac magnetic resonance as a tool for diagnosis, risk stratification and follow-up. Finally, we provide some practical recommendations about the need and timing of cardiac magnetic resonance examination for the management of patients with muscular dystrophy.

Effects of cardiac medications on ventricular function in patients with Duchenne muscular dystrophy-related cardiomyopathy

INTRODUCTION/AIMS

The DMD Care Considerations Working Group Guidelines 2010 recommended treating cardiac dystrophinopathy with angiotensin-converting enzyme-inhibitor (ACEi) and beta-blocker (BB) therapy to prevent the progressive decline in left ventricular function expected from earlier, natural history studies. The aim of this research was to audit change in measures of left ventricular function over 8 years to 4 years before and 4 years after deploying an ACEi/BB combination systematically at a dedicated "cardiology-muscle" clinic.

METHODS

This is an institutionally registered, retrospective, case-file-based audit of serial echocardiographic measures of left ventricular fractional shortening accumulated over the period 1995 to 2015.

RESULTS

Data from 104 genetically confirmed Duchenne muscular dystrophy (DMD) patients, aged 22.2 ± 5.3 years at data censure, were included. Mean age at first detection of left ventricular dysfunction was 15.1 ± 4.2 years, but older in those on maintenance steroid therapy (16.8 ± 4.2 vs 14.5 ± 4.1 years; P = .04). Group mean fractional shortening fell by 1.5%/year over the 4 years before therapy, but this decreased to 0.9%/year over the first 4 years after starting therapy. Analysis of limited left ventricular ejection fraction measures showed similar but nonsignificant changes. Neither age at detection of left ventricular dysfunction nor fractional shortening percent at time of therapy initiation affected the beneficial response.

DISCUSSION

The results support the international DMD recommendations of the time. This combination of cardiac medications helps stabilize heart function. For the best long-term effects, therapy needs to be initiated no later than on first detection left ventricular impairment.

Cardiac medication management in Duchenne muscular dystrophy

There have been significant improvements in the skeletal muscle and respiratory care for patients with Duchenne muscular dystrophy (DMD) over the last two decades. This has resulted in longer expected survival as many patients will live into their 20s and 30s. This timeline has resulted in a greater proportion of patients experiencing heart failure and cardiac-related mortality. Herein, we describe the current indications for medical therapy for patients with DMD.

The role of imaging in characterizing the cardiac natural history of Duchenne muscular dystrophy

Duchene muscular dystrophy (DMD) is a rare but devastating disease resulting in progressive loss of ambulation, respiratory failure, DMD-associated cardiomyopathy (DMD-CM), and premature death. The use of corticosteroids and supportive respiratory care has improved outcomes, such that DMD-CM is now the leading cause of death. Historically, most programs have focused on skeletal myopathy with less attention to the cardiac phenotype. This omission is rather astonishing since patients with DMD possess an absolute genetic risk of developing cardiomyopathy. Unfortunately, heart failure signs and symptoms are vague due to skeletal muscle myopathy leading to limited ambulation. Traditional assessment of cardiac symptoms by the New York Heart Association American College of Cardiology/American Heart Association Staging (ACC/AHA) classification is of limited utility, even in advanced stages. Echocardiographic assessment can detect cardiac dysfunction late in the disease course, but this has proven to be a poor surrogate marker of early cardiovascular disease and an inadequate predictor of DMD-CM. Indeed, one explanation for the paucity of cardiac therapeutic trials for DMD-CM has been the lack of a suitable end-point. Improved outcomes require a better proactive treatment strategy; however, the barrier to treatment is the lack of a sensitive and specific tool to assess the efficacy of treatment. The use of cardiac imaging has evolved from echocardiography to cardiac magnetic resonance imaging to assess cardiac performance. The purpose of this article is to review the role of cardiac imaging in characterizing the cardiac natural history of DMD-CM, highlighting the prognostic implications and an outlook on how this field might evolve in the future.

Cardiopulmonary phenotypic variability and discordance in Duchenne muscular dystrophy: Implications for new therapies

Neuromuscular respiratory medicine has traditionally focused on assisted lung ventilation and mucus clearance. These therapies have prolonged survival for patients with Duchenne muscular dystrophy (DMD). However, the field is rapidly evolving in a new direction: it is being revolutionized by molecular and genetic therapies. A good correlation between a patient's dystrophin mutation and his cardiopulmonary phenotype would allow accurate prediction of patient prognosis and would facilitate the design of studies that assess new DMD therapies. Instead, patient prognosis and the design of valid therapeutic studies are complicated by cardiopulmonary phenotypic discordance and variability, by which a notable proportion of DMD patients have unexpectedly good or poor cardiopulmonary function. The likely cause of phenotypic variability and discordance is genetic modifiers. Once the modifiers that affect cardiopulmonary function are better understood, it should be possible to create a personalized genetic profile that accurately predicts the prognosis of each individual DMD patient. This would allow investigators to assess the effect of new therapies in the context of each patient's particular cardiopulmonary natural history. Amplification of beneficial cardiopulmonary genetic modifiers and blocking of detrimental modifiers is a promising strategy for creating new DMD therapies. When patients with chronic respiratory failure are treated with assisted ventilation, cardiac function determines their survival. Therefore, prioritizing new cardiac therapies is most likely to prolong patient survival. By focusing on these topics we aim to move neuromuscular respiratory medicine beyond assisted ventilation and coughing and into the age of translational medicine.

A systematic review of pharmacologic therapies for the cardiomyopathy of Duchenne muscular dystrophy

OBJECTIVE

To perform a systematic review of studies evaluating pharmacologic therapies for the cardiomyopathy of Duchenne muscular dystrophy (DMD).

METHODS

PubMed, Google Scholar, and Embase were searched through October 8, 2020. Articles were selected using pre-determined criteria; 26 underwent detailed review by two co-authors. Study quality was assessed with the Newcastle-Ottawa scoring system (NOS); GRADE assessment evaluated their overall clinical importance.

RESULTS

There were few randomized controlled trials. Two of four trials of angiotensin converting enzyme inhibitors (ACEI) or ACEI plus beta-blockers (BB) found improved LV function. Two of two randomized trials of aldosterone antagonists (AA), when added to ACEI and BB therapy, demonstrated less decline of LV circumferential strain over 1 year of treatment. Observational studies of ACEI and BB had differing patient ages, symptomatology, cohort size, study duration and baseline heart function. LV function, assessed via unblinded imaging, was the most frequent outcome measure. LV dysfunction improved in some trials but was unconfirmed in others. Class IV heart failure patients had transient improvement of symptoms and LVEF. Most NOS scores reflected a low level of study quality. The Grade certainty rating, used for the summation of studies, was between "low" and "moderate."

CONCLUSION

Randomized trial evidence was inconsistent that either ACEI or BB or their combination improve LV function and/or alter progressive LV dysfunction. When ACEI and BB therapy are initiated for symptomatic Class IV heart failure, symptoms and LVEF improve transiently. AAs retard the rate of decline of LV function when initiated in younger DMD patients.

Role of the Renin-Angiotensin-Aldosterone System in Dystrophin-Deficient Cardiomyopathy

Dystrophin-deficient cardiomyopathy (DDC) is currently the leading cause of death in patients with dystrophinopathies. Targeting myocardial fibrosis (MF) has become a major therapeutic goal in order to prevent the occurrence of DDC. We aimed to review and summarize the current evidence about the role of the renin-angiotensin-aldosterone system (RAAS) in the development and perpetuation of MF in DCC. We conducted a comprehensive search of peer-reviewed English literature on PubMed about this subject. We found increasing preclinical evidence from studies in animal models during the last 20 years pointing out a central role of RAAS in the development of MF in DDC. Local tissue RAAS acts directly mainly through its main fibrotic component angiotensin II (ANG2) and its transducer receptor (AT1R) and downstream TGF-b pathway. Additionally, it modulates the actions of most of the remaining pro-fibrotic factors involved in DDC. Despite limited clinical evidence, RAAS blockade constitutes the most studied, available and promising therapeutic strategy against MF and DDC. Conclusion: Based on the evidence reviewed, it would be recommendable to start RAAS blockade therapy through angiotensin converter enzyme inhibitors (ACEI) or AT1R blockers (ARBs) alone or in combination with mineralocorticoid receptor antagonists (MRa) at the youngest age after the diagnosis of dystrophinopathies, in order to delay the occurrence or slow the progression of MF, even before the detection of any cardiovascular alteration.

Left Ventricular Magnetic Resonance Imaging Strain Predicts the Onset of Duchenne Muscular Dystrophy-Associated Cardiomyopathy

BACKGROUND

Early detection of left ventricular (LV) dysfunction before the onset of overt Duchenne muscular dystrophy-associated cardiomyopathy (DMDAC) may direct clinical management to slow onset of dysfunction. We aimed to assess whether LV strain will predict those who develop DMDAC.

METHODS

We performed a single center retrospective case control study of patients with Duchenne muscular dystrophy who underwent serial cardiac magnetic resonance between 2006 and 2019. Patients with Duchenne muscular dystrophy with an LV ejection fraction ≥55% on ≥1 cardiac magnetic resonance were identified and grouped into age-matched +DMDAC and -DMDAC. Within 3 years, +DMDAC had a subsequent cardiac magnetic resonance with a decline in LV ejection fraction ≥10% and absolute LV ejection fraction ≤50%. -DMDAC maintained an LV ejection fraction ≥55% on serial cardiac magnetic resonances. Two-dimensional and 3-dimensional global radial strain, global circumferential strain (GCS), and global longitudinal strain were measured using tissue tracking software and their ability to predict DMDAC onset was assessed. Multivariable analysis adjusted for late gadolinium enhancement.

RESULTS

Thirty +DMDAC and 30 age-matched -DMDAC patients were included with a total of 164 studies analyzed. Before DMDAC onset, 2-dimensional global radial strain and GCS were significantly worse in +DMDAC compared with -DMDAC (25.1±6.0 versus 29.0±6.3, P=0.011; -15.4%±2.4 versus -17.3%±2.6, P=0.003). Three-dimensional GCS and global radial strain had similar findings. Among strain measures, 3-dimensional GCS had the highest area under the curve to predict DMDAC in our cohort. These findings persisted after adjusting for the presence of late gadolinium enhancement.

CONCLUSIONS

Reduced global radial strain and GCS may predict those at risk for developing DMDAC before onset of LV dysfunction and its clinical utility warrants further exploration.

Mineralocorticoid receptor antagonism by finerenone is sufficient to improve function in preclinical muscular dystrophy

Aims

Duchenne muscular dystrophy (DMD) is an X‐linked inherited disease due to dystrophin deficiency causing skeletal and cardiac muscle dysfunction. Affected patients lose ambulation by age 12 and usually die in the second to third decades of life from cardiac and respiratory failure. Symptomatic treatment includes the use of anti‐inflammatory corticosteroids, which are associated with side effects including weight gain, osteoporosis, and increased risk of cardiovascular disease. Novel treatment options include blockade of the renin–angiotensin–aldosterone system, because angiotensin as well as aldosterone contribute to persistent inflammation and fibrosis, and aldosterone blockade represents an efficacious anti‐fibrotic approach in cardiac failure. Recent preclinical findings enabled successful clinical testing of a combination of steroidal mineralocorticoid receptor antagonists (MRAs) and angiotensin converting enzyme inhibitors in DMD boys. The efficacy of MRAs alone on dystrophic skeletal muscle and heart has not been investigated. Here, we tested efficacy of the novel non‐steroidal MRA finerenone as a monotherapy in a preclinical DMD model.

Methods and results

The dystrophin‐deficient, utrophin haploinsufficient mouse model of DMD was treated with finerenone and compared with untreated dystrophic and wild‐type controls. Grip strength, electrocardiography, cardiac magnetic resonance imaging, muscle force measurements, histological quantification, and gene expression studies were performed. Finerenone treatment alone resulted in significant improvements in clinically relevant functional parameters in both skeletal muscle and heart. Normalized grip strength in rested dystrophic mice treated with finerenone (40.3 ± 1.0 mN/g) was significantly higher (P = 0.0182) compared with untreated dystrophic mice (35.2 ± 1.5 mN/g). Fatigued finerenone‐treated dystrophic mice showed an even greater relative improvement (P = 0.0003) in normalized grip strength (37.5 ± 1.1 mN/g) compared with untreated mice (29.7 ± 1.1 mN/g). Finerenone treatment also led to significantly lower (P = 0.0075) susceptibility to limb muscle damage characteristic of DMD measured during a contraction‐induced injury protocol. Normalized limb muscle force after five lengthening contractions resulted in retention of 71 ± 7% of baseline force in finerenone‐treated compared with only 51 ± 4% in untreated dystrophic mice. Finerenone treatment also prevented significant reductions in myocardial strain rate (P = 0.0409), the earliest sign of DMD cardiomyopathy. Moreover, treatment with finerenone led to very specific cardiac gene expression changes in clock genes that might modify cardiac pathophysiology in this DMD model.

Conclusions

Finerenone administered as a monotherapy is disease modifying for both skeletal muscle and heart in a preclinical DMD model. These findings support further evaluation of finerenone in DMD clinical trials.

Stabilization of Early Duchenne Cardiomyopathy With Aldosterone Inhibition: Results of the Multicenter AIDMD Trial

Background Duchenne muscular dystrophy incurs nearly universal dilated cardiomyopathy by the third decade of life, preceded by myocardial damage and impaired left ventricular strain by cardiac magnetic resonance. It has been shown that (1) mineralocorticoid receptor antagonist therapy with spironolactone attenuated damage while maintaining function when given early in a mouse model and (2) low-dose eplerenone stabilized left ventricular strain in boys with Duchenne muscular dystrophy and evident myocardial damage but preserved ejection fraction. We hypothesized that moderate-dose spironolactone versus eplerenone would provide similar cardioprotection in this first head-to-head randomized trial of available mineralocorticoid receptor antagonists, the AIDMD (Aldosterone Inhibition in Duchenne Muscular Dystrophy) trial. Methods and Results This was a multicenter, double-blind, randomized, noninferiority trial. Subjects were randomized to eplerenone, 50 mg, or spironolactone, 50 mg, orally once daily for 12 months. The primary outcome was change in left ventricular systolic strain at 12 months. Among 52 enrolled male subjects, aged 14 (interquartile range, 12-18) years, spironolactone was noninferior to eplerenone (∆strain, 0.4 [interquartile range, -0.4 to 0.6] versus 0.2 [interquartile range, -0.2 to 0.7]; P=0.542). Renal and pulmonary function remained stable in both groups, and no subjects experienced serious hyperkalemia. Infrequent adverse events included gynecomastia in one subject in the spironolactone arm and facial rash in one subject in the eplerenone arm. Conclusions In boys with Duchenne muscular dystrophy and preserved left ventricular ejection fraction, spironolactone added to background therapy is noninferior to eplerenone in preserving contractile function. These findings support early mineralocorticoid receptor antagonist therapy as effective and safe in a genetic disease with high cardiomyopathy risk. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02354352.

The Role of Matrix Metalloproteinases and Tissue Inhibitors of Metalloproteinases in Duchenne Muscular Dystrophy Cardiomyopathy

BACKGROUND

Cardiomyopathy is the leading cause of death in Duchenne muscular dystrophy (DMD). Standard cardiac biomarkers are poor indicators of DMD cardiovascular disease. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) regulate collagen turnover. Given the cardiac fibrosis seen in DMD, we hypothesized that MMPs and TIMPs correlate with severity of DMD cardiomyopathy.

METHODS AND RESULTS

Prospectively enrolled DMD subjects (n = 42) underwent cardiac magnetic resonance imaging for function and late gadolinium enhancement (LGE), including LGE severity from 0 (no LGE) to 4 (severe). Serum from DMD and healthy male control subjects (n = 15) analyzed for MMPs 1, 2, 3, 7, 9, and 10 and TIMPs 1-4. MMP1, MMP7, and MMP10 were higher in DMD than in control (respectively, median 5080 pg/mL vs 2120 pg/mL [P = .007], 2170 pg/mL vs 1420 pg/mL [P < .001], and 216 pg/mL vs 140pg/mL [P = .040]); TIMP4 was lower in DMD (124 pg/mL vs 263 pg/mL; P = .046). Within DMD, MMP7 correlated inversely with left ventricular ejection fraction (r = -0.40; P = .012) and directly with strain (r = 0.54; P = .001) and LGE severity (r = 0.47; P = .003). MMP7 was higher in DMD patients with LGE compared with those without LGE and control subjects (P < .001).

CONCLUSIONS

Multiple MMPs are elevated in DMD compared with control subjects. MMP7 is related to DMD cardiac dysfunction and myocardial fibrosis, possibly through remodeling of the extracellular matrix.

Cardiopulmonary phenotypic discordance is common in Duchenne muscular dystrophy

OBJECTIVE

To determine the prevalence of discordant cardiopulmonary function among patients with Duchenne muscular dystrophy (DMD) in our clinic.

METHODS

Retrospective chart review from 1999 to 2017.

INCLUSION CRITERIA

DMD patients age ≥ 18 years, alive, with discordant cardiopulmonary function. No patients received glucocorticoid therapy. Discordant cardiopulmonary function was defined as either: good heart function (EF ≥ 40%) and bad lung function (FVC < 1 L) (Group A); or, bad heart function (EF < 40%) and good lung function (FVC ≥ 1 L) (Group B).

RESULTS

Among 74 eligible patients, 25 patients (34%) had discordant cardiopulmonary function (21 patients in Group A and 4 patients in Group B). Three dystrophin mutations were shared by >2 patients (nine patients with deletion of exon 44; three patients with deletion of exon 51; three patients with duplication of exon 2). Among the 15 patients with a shared genotype, eight patients (53%) had discordant cardiopulmonary function (five patients in group A, three patients in group B). Twenty-six patients had a deletion involving or distal to exon 45. Ten of these patients (38%) had discordant cardiopulmonary function (eight patients in Group A, two patients in Group B).

CONCLUSION

In our cohort of DMD patients, discordant cardiopulmonary function was common (present in one-third of our patients), and the dystrophin genotype did not reliably predict a patient's cardiopulmonary phenotype. If confirmed by larger, multi-center studies, our findings have significant implications for predicting patient prognosis, evaluating DMD therapies, and designing new DMD therapies.

ACE inhibition to slow progression of myocardial fibrosis in muscular dystrophies

Muscular dystrophy (MD) connotes a heterogeneous group of inherited disordersaffecting skeletal and cardiac muscle. Inseveral forms of MD, the cardiac disease may be the predominant manifestationof the underlying genetic myopathy. The cardiacinvolvement is due to progressive interstitial fibrosis and fatty replacement inboth the atria and ventricles, which may lead to cardiomyopathy, conductiondefects and tachyarrhythmias. Angiotensin-convertingenzyme inhibitors (ACE-Is) modulate the production of angiotensin II and limitthe amount of fibrosis in the myocardium, reducing mortality andhospitalization in cardiac patients. The aim of present review is to describethe antifibrotic proprieties of ACE inhibitor therapy and to summarize thecurrent body of scientific literature relating to the use of ACE-Is for theprevention and treatment of cardiomyopathy in patients with musculardystrophies.

Imaging the heart to detect cardiomyopathy in Duchenne muscular dystrophy: A review

Duchenne Muscular Dystrophy is the most common paediatric neuromuscular disorder. Mutations in the DMD gene on the X-chromosome result in progressive skeletal muscle weakness as the main clinical manifestation. However, cardiac muscle is also affected, with cardiomyopathy becoming an increasingly recognised cause of morbidity, and now the leading cause of mortality in this group. The diagnosis of cardiomyopathy has often been made late due to technical limitations in transthoracic echocardiograms and delayed symptomatology in less mobile patients. Increasingly, evidence supports earlier pharmacological intervention in cardiomyopathy to improve outcomes. However, the optimal timing of initiation remains uncertain, and the benefits of prophylactic therapy are unproven. Current treatment guidelines suggest initiation of therapy once cardiac dysfunction is detected. This review focuses on new and evolving techniques for earlier detection of Duchenne muscular dystrophy-associated cardiomyopathy. Transthoracic echocardiography or cardiac magnetic resonance imaging performed under physiological stress (dobutamine or exercise), can unmask early cardiac dysfunction. Cardiac magnetic resonance imaging can define cardiac function with greater accuracy and reliability than an echocardiogram, and is not limited by body habitus. Improved imaging techniques, used in a timely fashion, offer the potential for early detection of cardiomyopathy and improved long-term outcomes.

Progressive left ventricular dysfunction and long-term outcomes in patients with Duchenne muscular dystrophy receiving cardiopulmonary therapies

Objective

To describe the natural history of cardiomyopathy in patients with Duchenne muscular dystrophy (DMD) who are receiving contemporary therapies.

Methods

This is a single-institution retrospective cohort study of 57 patients aged >15 years with DMD. Serial digital echocardiograms were performed over a median follow-up of 8 years. Left ventricular dysfunction (LVD) was defined as shortening fraction (SF) <29% plus focal wall motion abnormalities. Therapies included ACE inhibitors, beta-blockers and assisted ventilation.

Results

The SF declined progressively in 53/57 patients (93%). LVD occurred in 40 of 57 patients (70%), with variable age at onset (median 18 years, IQR 14–21.5 years). Rate of SF decline (–1.51%±1.16%/year) was variable and unrelated to genotype. However, survival was shorter for patients with LVD onset at age <18 years vs onset at ≥18 years (death at 21.1±2.5 years vs 33.1±4.4 years; P<0.001). Death occurred in 27/57 (47%) patients at a median age of 26.3 years (IQR 20.6–31.5). Death was preceded by LVD in 22/27 patients (81%), 15 (68%) of whom developed class 4 heart failure (CHF). Time from CHF to death was brief (median 8.0 months).

Conclusion

Despite contemporary therapies, SF declined progressively in almost all patients. Age at onset of LVD and age at death were variable and unrelated to genotype; however, survival was shortened for patients with LVD onset at age <18 years. Death was usually preceded by LVD. CHF was a sentinel event, with death occurring shortly thereafter.

Cardiac profile of asymptomatic children with Becker and Duchenne muscular dystrophy under treatment with steroids and with/without perindopril

BACKGROUND

To evaluate cardiovascular function in boys with Duchenne (DMD) and Becker (BMD) muscular dystrophy, using cardiac magnetic resonance (CMR).

METHODS

This is a single point cross sectional study of twenty-four boys with genetically ascertained DMD, and 10 with BMD, aged 10.5 ± 1.5 years (range 9-13), were prospectively evaluated by a 1.5 T system and compared with those of age-sex matched controls. The DMD patients were divided in 2 groups. Group A (N = 12) were under treatment with both deflazacort and perindopril, while Group B (n = 12) were under treatment with deflazacort, only. BMD patients did not take any medication. Biventricular function was assessed using a standard SSFP sequence. Late gadolinium enhancement (LGE) was assessed from T1 images taken 15 min after injection of 0.2 mg/Kg gadolinium DTPA using a 3D-T1-TFE sequence.

RESULTS

Group A and BMDs were asymptomatic with normal ECG, 24 h ECG recording and echocardiogram. Group B were asymptomatic but 6/12 had abnormal ECG and mildly impaired LVEF. Their 24 h ECG recording revealed supraventricular and ventricular extrasystoles (all at 12-13 yrs). LV indices in Group A and BMD did not differ from those of controls. However, LV indices in Group B were significantly impaired compared with controls, Group A and BMDs (p < 0.001). An epicardial LGE area = 3 ± 0.5% of LV mass was identified in the posterolateral wall of LV only in 6/12 patients of Group B, but in not in any BMD or Group A.

CONCLUSION

Children with either BMD or DMD under treatment with both deflazacort and perindopril present preserved LV function and lack of LGE. However, further large scale multicenter studies are warranted to confirm these data, including further CMR mapping approaches.

Pharmacological therapy for the prevention and management of cardiomyopathy in Duchenne muscular dystrophy: A systematic review

Cardiomyopathy is a major source of morbidity and mortality in Duchenne muscular dystrophy (DMD) patients now that respiratory care has improved. There is currently no definitive evidence guiding the management of DMD-associated cardiomyopathy (DMD-CM). The objective of this systematic review was to evaluate the effectiveness of pharmacotherapies for the prevention and/or management of DMD-CM and to determine the optimal timing to commence these interventions. A systematic search was conducted in January 2016 using MEDLINE, EMBASE and CINAHL databases and grey literature sources for studies evaluating the use of angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers, beta-blockers or aldosterone antagonists. Study quality assessment was conducted using the Downs and Black quality assessment checklist. PRISMA reporting guidelines were used. Of the 15 studies included in this review, most were of low methodological quality. Meta-analysis was not possible due to heterogeneity of studies. ACE inhibitors, angiotensin receptor blockers, beta-blockers and/or aldosterone antagonists tended to improve or preserve left ventricular systolic function and delay the progression of DMD-CM. While there is evidence supporting the use of heart failure medication in patients with DMD, data regarding these interventions for delaying the onset of DMD-CM and when to initiate therapy are lacking. PROSPERO registration: CRD42015029555.

A Case of Refractory Heart Failure in Becker Muscular Dystrophy Improved With Corticosteroid Therapy

The patient was a 26 year-old man who was referred to our hospital in June 2011 because of severe heart failure. At age 24 years, he was found to have Becker muscular dystrophy. He received enalapril for cardiac dysfunction; however, he had worsening heart failure and was thus referred to our hospital. Echocardiography showed enlargement of the left ventricle, with a diastolic dimension of 77 mm and ejection fraction of 19%. His condition improved temporarily after an infusion of dobutamine and milrinone. He was then administered amiodarone for ventricular tachycardia; however, he subsequently developed hemoptysis. Amiodarone was discontinued and corticosteroid pulse therapy was administered followed by oral prednisolone (PSL). His creatinine phosphokinase (CPK) level and cardiomegaly improved after the corticosteroid therapy. The PSL dose was reduced gradually, bisoprolol was introduced, and the catecholamine infusion was tapered. A cardiac resynchronization device was implanted; however, the patient's condition gradually worsened, which necessitated dobutamine infusion for heart failure. We readministered 30 mg PSL, which decreased the CPK level and improved the cardiomegaly. The dobutamine infusion was discontinued, and the patient was discharged. He was given 7.5 mg PSL as an outpatient, and he returned to normal life without exacerbation of the heart failure. There are similar reports showing that corticosteroids are effective for skeletal muscle improvement in Duchenne muscular dystrophy; however, their effectiveness for heart failure has been rarely reported. We experienced a case of Becker muscular dystrophy in which corticosteroid therapy was effective for refractory heart failure.

Increased myocardial native T1 and extracellular volume in patients with Duchenne muscular dystrophy

BACKGROUND

Duchenne muscular dystrophy (DMD) cardiomyopathy is a progressive disease for which there is no cure. Disease-specific therapies are needed that can be initiated before irreversible myocardial damage ensues. In order to evaluate therapeutic efficacy, surrogate endpoints other than ejection fraction must be found. The hypothesis of this study is that T1 and extracellular volume fraction (ECV) mapping using cardiovascular magnetic resonance (CMR) can detect diffuse extracellular matrix expansion in DMD patients with normal left ventricular ejection fraction (LVEF) and without myocardial late gadolinium enhancement (LGE).

METHODS

Thirty-one DMD and 11 healthy control participants were prospectively enrolled. CMR using a modified Look-Locker (MOLLI) sequence was performed in all participants before and after contrast administration. T1 and ECV maps of the mid left ventricular myocardium were generated and regions of interest were contoured using the standard 6-segment AHA model. Global and segmental values were compared between DMD and controls using a Wilcoxon rank-sum test.

RESULTS

The DMD participants had significantly higher mean native T1 compared with controls (1045 ms vs. 988 ms, p = 0.001). DMD participants with normal LVEF and without evidence of LGE also demonstrated elevated mean native T1 (1039 ms vs. 988 ms, p = 0.002, and 1038 ms vs. 988 ms, p = 0.011). DMD participants had a significantly greater mean ECV than controls (0.31 vs. 0.24, p < 0.001), even in the settings of normal LVEF (0.28 vs. 0.24, p < 0.001) and negative LGE (0.29 vs. 0.24, p = 0.001).

CONCLUSIONS

DMD participants have elevated LV myocardial native T1 and ECV, even in the setting of normal LVEF and in the absence of LGE. T1 and ECV mapping in DMD have potential to serve as surrogate cardiomyopathy outcome measures for clinical trials.

Pathoproteomic profiling of the skeletal muscle matrisome in dystrophinopathy associated myofibrosis

The gradual accumulation of collagen and associated proteins of the extracellular matrix is a crucial myopathological parameter of many neuromuscular disorders. Progressive tissue damage and fibrosis play a key pathobiochemical role in the dysregulation of contractile functions and often correlates with poor motor outcome in muscular dystrophies. Following a brief introduction into the role of the extracellular matrix in skeletal muscles, we review here the proteomic profiling of myofibrosis and its intrinsic role in X-linked muscular dystrophy. Although Duchenne muscular dystrophy is primarily a disease of the membrane cytoskeleton, one of its most striking histopathological features is a hyperactive connective tissue and tissue scarring. We outline the identification of novel factors involved in the modulation of the extracellular matrix in muscular dystrophy, such as matricellular proteins. The establishment of novel proteomic markers will be helpful in improving the diagnosis, prognosis, and therapy monitoring in relation to fibrotic substitution of contractile tissue. In the future, the prevention of fibrosis will be crucial for providing optimum conditions to apply novel pharmacological treatments, as well as establish cell-based approaches or gene therapeutic interventions. The elimination of secondary abnormalities in the matrisome promises to reduce tissue scarring and the loss of skeletal muscle elasticity.

Comparative Label-Free Mass Spectrometric Analysis of Mildly versus Severely Affected mdx Mouse Skeletal Muscles Identifies Annexin, Lamin, and Vimentin as Universal Dystrophic Markers

The primary deficiency in the membrane cytoskeletal protein dystrophin results in complex changes in dystrophic muscles. In order to compare the degree of secondary alterations in differently affected subtypes of skeletal muscles, we have conducted a global analysis of proteome-wide changes in various dystrophin-deficient muscles. In contrast to the highly degenerative mdx diaphragm muscle, which showed considerable alterations in 35 distinct proteins, the spectrum of mildly to moderately dystrophic skeletal muscles, including interosseus, flexor digitorum brevis, soleus, and extensor digitorum longus muscle, exhibited a smaller number of changed proteins. Compensatory mechanisms and/or cellular variances may be responsible for differing secondary changes in individual mdx muscles. Label-free mass spectrometry established altered expression levels for diaphragm proteins associated with contraction, energy metabolism, the cytoskeleton, the extracellular matrix and the cellular stress response. Comparative immunoblotting verified the differences in the degree of secondary changes in dystrophin-deficient muscles and showed that the up-regulation of molecular chaperones, the compensatory increase in proteins of the intermediate filaments, the fibrosis-related increase in collagen levels and the pathophysiological decrease in calcium binding proteins is more pronounced in mdx diaphragm as compared to the less severely affected mdx leg muscles. Annexin, lamin, and vimentin were identified as universal dystrophic markers.

Dystrophin genotype-cardiac phenotype correlations in Duchenne and Becker muscular dystrophies using cardiac magnetic resonance imaging

Duchenne and Becker muscular dystrophies are caused by mutations in dystrophin. Cardiac manifestations vary broadly, making prognosis difficult. Current dystrophin genotype-cardiac phenotype correlations are limited. For skeletal muscle, the reading-frame rule suggests in-frame mutations tend to yield milder phenotypes. We performed dystrophin genotype-cardiac phenotype correlations using a protein-effect model and cardiac magnetic resonance imaging. A translational model was applied to patient-specific deletion, indel, and nonsense mutations to predict exons and protein domains present within truncated dystrophin protein. Patients were dichotomized into predicted present and predicted absent groups for exons and protein domains of interest. Development of myocardial fibrosis (represented by late gadolinium enhancement [LGE]) and depressed left ventricular ejection fraction (LVEF) were compared. Patients (n = 274) with predicted present cysteine-rich domain (CRD), C-terminal domain (CTD), and both the N-terminal actin-binding and cysteine-rich domains (ABD1 + CRD) had a decreased risk of LGE and trended toward greater freedom from LGE. Patients with predicted present CTD (exactly the same as those with in-frame mutations) and ABD1 + CRD trended toward decreased risk of and greater freedom from depressed LVEF. In conclusion, genotypes previously implicated in altering the dystrophinopathic cardiac phenotype were not significantly related to LGE and depressed LVEF. Patients with predicted present CRD, CTD/in-frame mutations, and ABD1 + CRD trended toward milder cardiac phenotypes, suggesting that the reading-frame rule may be applicable to the cardiac phenotype. Genotype-phenotype correlations may help predict the cardiac phenotype for dystrophinopathic patients and guide future therapies.

Myocardial fibrosis burden predicts left ventricular ejection fraction and is associated with age and steroid treatment duration in duchenne muscular dystrophy

Background

Patients with Duchenne muscular dystrophy exhibit progressive cardiac and skeletal muscle dysfunction. Based on prior data, cardiac dysfunction in Duchenne muscular dystrophy patients may be influenced by myocardial fibrosis and steroid therapy. We examined the longitudinal relationship of myocardial fibrosis and ventricular dysfunction using cardiac magnetic resonance in a large Duchenne muscular dystrophy cohort.

Methods and Results

We reviewed 465 serial cardiac magnetic resonance studies (98 Duchenne muscular dystrophy patients with ≥4 cardiac magnetic resonance studies) for left ventricular ejection fraction (LVEF) and presence of late gadolinium enhancement (LGE), a marker for myocardial fibrosis. LVEF was modeled by examining LGE status, myocardial fibrosis burden (as assessed by the number of LGE‐positive left ventricular segments), patient age, and steroid treatment duration. An age‐only model demonstrated that LVEF declined 0.58±0.10% per year. In patients with both LGE‐negative and LGE‐positive studies (n=51), LVEF did not decline significantly over time if LGE was absent but declined 2.2±0.31% per year when LGE was present. Univariate modeling showed significant associations between LVEF and steroid treatment duration, presence of LGE, and number of LGE‐positive left ventricular segments; multivariate modeling showed that LVEF declined by 0.93±0.09% for each LGE‐positive left ventricular segment, whereas age and steroid treatment duration were not significant. The number of LGE‐positive left ventricular segments increased with age, and longer steroid treatment duration was associated with lower age‐related increases.

Conclusion

Progressive myocardial fibrosis, as detected by LGE, was strongly correlated with the LVEF decline in Duchenne muscular dystrophy patients. Longer steroid treatment duration was associated with a lower age‐related increase in myocardial fibrosis burden.

Eplerenone for early cardiomyopathy in Duchenne muscular dystrophy: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Cardiomyopathy is a leading cause of death in patients with Duchenne muscular dystrophy and myocardial damage precedes decline in left ventricular systolic function. We tested the efficacy of eplerenone on top of background therapy in patients with Duchenne muscular dystrophy with early myocardial disease.

METHODS

In this randomised, double-blind, placebo-controlled trial, boys from three centres in the USA aged 7 years or older with Duchenne muscular dystrophy, myocardial damage by late gadolinium enhancement cardiac MRI and preserved ejection fraction received either eplerenone 25 mg or placebo orally, every other day for the first month and once daily thereafter, in addition to background clinician-directed therapy with either angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). Computer-generated randomisation was done centrally using block sizes of four and six, and only the study statistician and the investigational pharmacy had the preset randomisation assignments. The primary outcome was change in left ventricular circumferential strain (Ecc) at 12 months, a measure of contractile dysfunction. Safety was established through serial serum potassium levels and measurement of cystatin C, a non-creatinine measure of kidney function. This trial is registered with ClinicalTrials.gov, number NCT01521546.

FINDINGS

Between Jan 26, 2012, and July 3, 2013, 188 boys were screened and 42 were enrolled. 20 were randomly assigned to receive eplerenone and 22 to receive placebo, of whom 20 in the eplerenone group and 20 in the placebo group completed baseline, 6-month, and 12-month visits. After 12 months, decline in left ventricular circumferential strain was less in those who received eplerenone than in those who received placebo (median ΔEcc 1·0 [IQR 0·3-2·2] vs 2·2 [1·3-3·1]; p=0·020). Cystatin C concentrations remained normal in both groups, and all non-haemolysed blood samples showed normal potassium concentrations. One 23-year-old patient in the placebo group died of fat embolism, and another patient in the placebo group withdrew from the trial to address long-standing digestive issues. All other adverse events were mild: short-lived headaches coincident with seasonal allergies occurred in one patient given eplerenone, flushing occurred in one patient given placebo, and anxiety occurred in another patient given placebo.

INTERPRETATION

In boys with Duchenne muscular dystrophy and preserved ejection fraction, addition of eplerenone to background ACEI or ARB therapy attenuates the progressive decline in left ventricular systolic function. Early use of available drugs warrants consideration in this population at high risk of cardiac death, but further studies are needed to determine the effect of combination cardioprotective therapy on event-free survival in Duchenne muscular dystrophy.

FUNDING

BallouSkies, Parent Project for Muscular Dystrophy, US National Center for Advancing Translational Sciences, and US National Institutes of Health.

[Current care strategies for Duchenne muscular dystrophy]

BACKGROUND

The medical care of patients with Duchenne muscular dystrophy (DMD) is an interdisciplinary and multifaceted task. The vast majority of those affected show a nearly constant course which is reflected in a corresponding stage-oriented treatment concept. Although there is still no causal therapy available for DMD, the course and in particular the quality of life of patients can be decisively improved by established medical practices.

THERAPEUTIC STRATEGIES

The orthopedic problems of DMD patients include contractures of the upper and lower extremities as well as sitting instability due to progressive scoliosis with pelvic imbalance. The orthopedic treatment incorporates conservative measures, such as physiotherapy, provision of orthotic devices and wheelchairs as well as surgery to resolve contractures of the lower extremities and surgical stabilization of the spine. Furthermore, in these patients orthopedic surgeons and trauma surgeons are confronted with the treatment and prophylaxis of fractures induced by osteoporosis. An early onset of glucocorticoid therapy markedly delays the loss of motor abilities.

TREATMENT ASPECTS

An important aspect in the care of DMD patients is the timely prophylaxis and treatment of respiratory insufficiency with regular sessions of breathing therapy, learning breathing and coughing techniques and the sufficiently early start of non-invasive mechanically assisted ventilation. Of similar relevance are also the early recognition and cardioprotective treatment of cardiomyopathy.

CONCLUSION

The orthopedic surgeon accompanies the patient and family through all stages of the disease and must be appropriately informed on current management and treatment strategies even outside the limits of the personal field of specialization.

Review of Journal of Cardiovascular Magnetic Resonance 2012

There were 90 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2012, which is an 8% increase in the number of articles since 2011. The quality of the submissions continues to increase. The editors are delighted to report that the 2011 JCMR Impact Factor (which is published in June 2012) has risen to 4.44, up from 3.72 for 2010 (as published in June 2011), a 20% increase. The 2011 impact factor means that the JCMR papers that were published in 2009 and 2010 were cited on average 4.44 times in 2011. The impact factor undergoes natural variation according to citation rates of papers in the 2 years following publication, and is significantly influenced by highly cited papers such as official reports. However, the progress of the journal's impact over the last 5 years has been impressive. Our acceptance rate is approximately 25%, and has been falling as the number of articles being submitted has been increasing. In accordance with Open-Access publishing, the JCMR articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. For this reason, the Editors have felt that it is useful once per calendar year to summarize the papers for the readership into broad areas of interest or theme, so that areas of interest can be reviewed in a single article in relation to each other and other recent JCMR articles. The papers are presented in broad themes and set in context with related literature and previously published JCMR papers to guide continuity of thought in the journal. We hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality manuscripts to JCMR for publication.

The Role of Cardiovascular Magnetic Resonance (CMR) and Computed Tomography (CCT) in Facilitating Heart Failure Management

OPINION STATEMENT

Cardiovascular magnetic resonance (CMR) and cardiac computed tomography (CCT) offer advantages for detecting left or right ventricular dysfunction in patients with or suspected of heart failure. CMR does not expose patients to ionizing radiation, and thus is well-suited for functional assessments and serial studies. CCT provides high spatial resolution, making it useful for the identification of coronary arteriosclerosis associated with ischemic cardiomyopathy. In this review, the clinical applications of CMR and CCT are individually discussed, with comparisons made between them to examine the strengths of each modality. The major techniques for each modality are outlined, as well as their uses for the evaluation of cardiomyopathy in heart failure patients with reduced left ventricular ejection fraction, preserved left ventricular ejection fraction, and valvular heart disease. Finally, we review the utility of CMR and CCT in determining which patients will benefit from cardiac resynchronization therapy.

Abnormal circumferential strain is present in young Duchenne muscular dystrophy patients

Advances in management of non-cardiac issues in Duchenne muscular dystrophy (DMD) have improved such that DMD-associated cardiac disease has become the leading cause of death for such patients. Cardiac dysfunction measured by standard transthoracic echocardiographic methods, e.g., fractional shortening (FS) and ejection fraction (EF), is rarely present during the first decade of life. The current study used transthoracic echocardiogram (TTE) to assess strain (ε), an indicator of regional ventricular function, in young DMD patients. A retrospective review of the TTE database was performed. TTE results from DMD patients <8 years (n = 63) performed during 2009 to 2010 were compared with TTE results from an unaffected control group (n = 61). Feature tracking analysis software was used to measure total circumferential strain (ε cc) as well as segmental ε cc based on the American Society of Echocardiography 16-segment model. Although there were no differences in FS, the absolute value for left-ventricular (LV) ε cc at the mid-chamber level was decreased in DMD (-21.7 % ± 3.8 % vs. -19.8 % ± 4.2 %, p < 0.01; unaffected vs. DMD). Segmental ε(cc) was similarly affected in the anteroseptal segment (-23.0 % ± 6.1 % vs. -18.9 % ± 7.0 %, p = 0.001; controls vs. DMD), the inferior segment (-20.7 % ± 5.16 % vs. -17.7 % ± 6.1 %, p = 0.003; controls vs. DMD), and the inferolateral segment (-18.3 % ± 6.2 % vs. -15.9 % ± 6.7 %, p = 0.04; controls vs. DMD). In the present study we demonstrate both total and segmental LV ε cc (anteroseptal, inferior, and inferolateral segments) abnormalities at the mid-chamber level in a large group of young DMD patients with normal FS. These novel findings substantiate that the disease process is present and results in abnormal myocardial function before standard measures detect global dysfunction.

Cardiac and respiratory dysfunction in Duchenne muscular dystrophy and the role of second messengers

Duchenne muscular dystrophy (DMD) affects young boys and is characterized by the absence of dystrophin, a large cytoskeletal protein present in skeletal and cardiac muscle cells and neurons. The heart and diaphragm become necrotic in DMD patients and animal models of DMD, resulting in cardiorespiratory failure as the leading cause of death. The major consequences of the absence of dystrophin are high levels of intracellular Ca(2+) and the unbalanced production of NO that can finally trigger protein degradation and cell death. Cytoplasmic increase in Ca(2+) concentration directly and indirectly triggers different processes such as necrosis, fibrosis, and activation of macrophages. The absence of the neuronal isoform of nitric oxide synthase (nNOS) and the overproduction of NO by the inducible isoform (iNOS) further increase the intracellular Ca(2+) via a hypernitrosylation of the ryanodine receptor. NO overproduction, which further induces the expression of iNOS but decreases the expression of the endothelial isoform (eNOS), deregulates the muscle tissue blood flow creating an ischemic situation. The high levels of Ca(2+) in dystrophic muscles and the ischemic state of the muscle tissue would culminate in a positive feedback loop. While efforts continue toward optimizing cardiac and respiratory care of DMD patients, both Ca(2+) and NO in cardiac and respiratory muscle pathways have been shown to be important to the etiology of the disease. Understanding the mechanisms behind the fine regulation of Ca(2+) -NO may be important for a noninterventional and noninvasive supportive approach to treat DMD patients, improving the quality of life and natural history of DMD patients.

Pharmacological therapies for muscular dystrophies

PURPOSE OF REVIEW

The study reviews recent advances in pharmacological management of muscular dystrophies. Similarities and differences among the pathophysiology of different forms of muscular dystrophy lead to a broad array of approaches to provide new treatments.

RECENT FINDINGS

In this review, we include only those muscular dystrophies for which advances have been published in the past year. This represents the 'advancing edge' of a large body of research over more than 20 years. This runs the gamut of new discoveries in symptomatic management to mutation-specific strategies that attempt to correct the root cause of the disorder.

SUMMARY

The field of pharmacological therapies for the muscular dystrophies continues to steadily advance. It is encouraging that research into new therapies is increasingly exploring pharmacological strategies with the potential to ameliorate disease pathology to a clinically significant degree.

Review of Journal of Cardiovascular Magnetic Resonance 2011

There were 83 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2011, which is an 11% increase in the number of articles since 2010. The quality of the submissions continues to increase. The editors had been delighted with the 2010 JCMR Impact Factor of 4.33, although this fell modestly to 3.72 for 2011. The impact factor undergoes natural variation according to citation rates of papers in the 2 years following publication, and is significantly influenced by highly cited papers such as official reports. However, we remain very pleased with the progress of the journal's impact over the last 5 years. Our acceptance rate is approximately 25%, and has been falling as the number of articles being submitted has been increasing. In accordance with Open-Access publishing, the JCMR articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. For this reason, the Editors feel it is useful to summarize the papers for the readership into broad areas of interest or theme, which we feel would be useful, so that areas of interest from the previous year can be reviewed in a single article in relation to each other and other recent JCMR articles. The papers are presented in broad themes and set in context with related literature and previously published JCMR papers to guide continuity of thought in the journal. We hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality manuscripts to JCMR for publication.

New imaging modalities to assess cardiac function: not just pretty pictures

PURPOSE OF REVIEW

The following review will focus on the current advances in both echocardiography and cardiovascular MRI (CMRI) in the assessment of cardiac function.

RECENT FINDINGS

The assessment of cardiac function in pediatric patients and in congenital heart disease (CHD) patients has dramatically improved over the last several years. The advancement of transthoracic echocardiography with tissue Doppler imaging, speckle tracking, and three-dimensional echocardiography has enabled strain assessment and the ability to estimate ventricular volumes in these complex patients. In the last few decades, CMRI has become an imaging modality that is now part of the standard tools used for cardiac assessment. With superb two-dimensional and three-dimensional resolution, CMRI allows clear delineation of cardiac and extracardiac structures as well as accurate and reproducible assessment of ventricular volume and function. The most recent and robust contributions of CMRI are its ability to provide characterization of the myocardium and the development of new measurements of global and regional myocardial mechanics and function.

SUMMARY

Recent advances in echocardiography and CMRI allow a better understanding of myocardial mechanics and composition as well as accurate assessment of ventricular volume and global and regional function in the complex and unique anatomy often found in CHD patients.

Treatment of dystrophinopathic cardiomyopathy: review of the literature and personal results

Cardiomyopathy is an almost universal finding in boys affected by Duchenne muscular dystrophy (DMD). Myocardial changes, as a result of the lack of dystrophin, consist of cell membrane degradation, interstitial inflammation, fatty replacement and fibrosis. Dystrophinopathic cardiomyopathy generally starts as a preclinical or intermediate stage, with evolution toward advanced stages characterized by ventricle enlargement but also by symptoms and signs of heart failure (dyspnoea, peripheral edema and liver enlargement). However in few patients the dilation could be the first manifestation of the heart involvement. The ability to detect overt cardiomyopathy increases with age, such that more than 80% of boys older than 18 years will have abnormal systolic function. Several drugs have been employed with the aim to contrast the evolution of cardiomyopathy toward stages of severe congestive heart failure. A review of cardiac treatment in DMD and personal experience are reported and discussed.