Research report: Case Report: Twelve-year longitudinal CMR follow-up in Becker muscular dystrophy–associated cardiomyopathy

Serial cardiac magnetic resonance imaging in a 57-year-old man with genetically confirmed Becker muscular dystrophy documented substantial progression of heart involvement over 12 years, including enlarged left ventricular volume, reduced pumping function, worsening strain and more extensive myocardial fibrosis. The single-patient case report compared examinations performed in 2014 and 2026, showing a transition from mild systolic impairment and limited lateral-wall scarring to pronounced ventricular remodelling, impaired myocardial mechanics and nearly circumferential fibrosis. The findings illustrate how repeated CMR can document changes in cardiac structure, function and tissue within the same person, although one case cannot establish the typical course of disease across a wider population.

Becker muscular dystrophy is an inherited dystrophinopathy characterized by progressive skeletal muscle weakness, but cardiac involvement may develop independently of the severity of the muscle disease. Dilated cardiomyopathy is an important cause of morbidity and mortality in people with the condition. The reported patient first presented in 2013, at age 44, with chest pain and a markedly elevated cardiac troponin level of 10,000 ng/L.

Electrocardiography showed right bundle branch block, while invasive coronary angiography revealed unobstructed coronary arteries. During subsequent follow-up, he reported progressive fatigue and reduced exercise tolerance. These events led clinicians to investigate whether myocardial disease associated with Becker muscular dystrophy could account for his cardiac symptoms and ventricular dysfunction.

Because echocardiography had shown a mildly reduced left ventricular ejection fraction and the patient had recent symptoms, CMR was performed in 2014 on a 1.5-tesla Philips Ingenia scanner. The examination showed a normal-sized left ventricle with mild concentric hypertrophy, including a maximum septal wall thickness of 13 mm. Global systolic dysfunction was mild, with left ventricular ejection fraction measured at 49%.

Late gadolinium enhancement revealed subepicardial fibrosis involving the lateral wall, a distribution the investigators considered typical of cardiac involvement in Becker muscular dystrophy. The right ventricle was documented as normal in size and function, and mild central mitral regurgitation was present. Myocarditis was considered in the differential diagnosis, but the location and distribution of the fibrosis supported Becker muscular dystrophy-associated cardiomyopathy.

Over the following 12 years, the patient remained under regular clinical follow-up, with interval cardiac assessment and serial echocardiography showing a continuing decline in left ventricular ejection fraction. In 2022, he experienced a non-ST-elevation myocardial infarction and underwent percutaneous coronary intervention with placement of a drug-eluting stent, leaving no residual coronary artery disease. At his latest clinic visit in 2025, he reported worsening breathlessness but denied chest pain, palpitations or syncope.

In early 2026, at age 57, he developed acute decompensated heart failure characterized by rapidly progressive breathlessness and lower-limb edema, which improved after diuretic therapy. Transthoracic echocardiography placed left ventricular ejection fraction at 35%–40%, prompting repeat CMR to reassess ventricular size, function and scar progression. The 2026 CMR, performed on a 3.0-tesla Philips Achieva scanner, quantified major interval changes in the left ventricle.

End-diastolic volume rose from 199 mL in 2014 to 258 mL in 2026, while the value indexed to body surface area increased from 89 to 123 mL/m². Left ventricular ejection fraction fell from 49% to 37%. Ventricular mass increased from 194 g to 226 g, and the indexed mass rose from 87 to 108 g/m².

Maximum septal wall thickness increased from 13 mm to 19 mm. Feature-tracking analysis recorded deterioration in all three reported global strain measures: global longitudinal strain changed from −14.3% to −11.5%, global circumferential strain from −14.9% to −11.4%, and global radial strain from 22.4% to 15.8%. The follow-up examination also quantified a right ventricular end-diastolic volume of 219 mL, an indexed value of 104 mL/m², and a right ventricular ejection fraction of 38%.

Late gadolinium enhancement had also changed substantially. The original subepicardial lateral-wall fibrosis became more extensive, and new mid-wall fibrosis appeared in the interventricular septum. Together, the enhancement formed a diffuse, contiguous subepicardial pattern approaching circumferential involvement.

Despite the patient’s 2022 myocardial infarction, the follow-up scan showed no late gadolinium enhancement in an ischemic distribution suggesting infarction scar. Native T1 mapping was available only in 2026; the global myocardial value was 1,360 milliseconds, above the institutional reference range of 1,147–1,238 milliseconds. That elevated value is nonspecific and may reflect myocardial fibrosis, edema or both, particularly in the context of recent cardiac decompensation, so the absence of a baseline T1 measurement prevents direct assessment of changes in native tissue properties over time.

Although the examinations used different scanners and magnetic-field strengths, the investigators employed broadly comparable acquisition techniques. Both included balanced steady-state free-precession cine imaging in standard long-axis views and a contiguous short-axis stack covering the ventricles from base to apex. Late gadolinium images were acquired with an inversion-recovery sequence approximately 10 minutes after intravenous administration of gadobutrol at 0.15 mmol/kg.

Both examinations were analyzed with the same cvi42 software, using consistent ventricular contouring and feature-tracking methods. Endo- and epicardial myocardial borders were manually traced in the end-diastolic phase of two- and four-chamber views and short-axis cine images. Software then tracked the motion of in-plane tissue voxels through the cardiac cycle.

Two- and four-chamber long-axis views supplied global longitudinal strain, while short-axis views supplied global circumferential and radial strain. The case provides a long-term within-patient comparison in a field where longitudinal CMR reports in Becker muscular dystrophy remain limited and reported follow-up periods are generally shorter. Prior studies cited by the authors have detected late gadolinium enhancement in as many as 73% of people with Becker muscular dystrophy, most often in a subepicardial inferolateral distribution.

Fibrosis and abnormal left ventricular function have also been identified in patients with otherwise normal electrocardiographic and echocardiographic findings, and fibrotic changes may precede overt systolic dysfunction. The baseline CMR in this patient already showed two indicators of myocardial involvement: an ejection fraction of 49% and global longitudinal strain of −14.3%, which the authors considered impaired. The subsequent decrease in longitudinal strain, accompanied by worse circumferential and radial strain, coincided with expanding fibrosis and lower ejection fraction.

These measurements documented progressive impairment of myocardial mechanics, but their temporal association does not establish causation among the imaging findings. Several limitations constrain the conclusions that can be drawn. The report includes one patient and only two CMR time points, preventing assessment of when progression begins or of the rate at which cardiac involvement develops in Becker muscular dystrophy generally.

Differences in acquisition protocols, intervening clinical events and treatment changes may have influenced the observed findings. Late gadolinium enhancement was evaluated qualitatively rather than quantified, and the lack of baseline native T1 mapping prevented direct longitudinal tissue characterization. The authors interpreted the increase in maximum septal thickness cautiously, considering it most likely to reflect progression of Becker muscular dystrophy because it occurred alongside deteriorating ejection fraction, ventricular remodelling and increasing fibrosis rather than as an isolated change.

The case therefore records a longitudinal pattern in one individual; it does not establish population-wide rates, causal mechanisms or the effect of any treatment. At the time of the report, the patient was receiving an angiotensin receptor-neprilysin inhibitor at 49/51 mg twice daily, bisoprolol at 2.5 mg once daily, spironolactone at 25 mg once daily and furosemide at 40 mg once daily. Spironolactone was added after the CMR examination, and echocardiography was requested to assess the response to heart-failure medication; no subsequent clinical event was recorded.

The report does not establish that a particular medication altered the imaging trajectory. Its central result is that serial CMR can document the evolving myocardial phenotype of Becker muscular dystrophy-associated cardiomyopathy by combining ventricular volumes, ejection fraction, strain, native T1 and late gadolinium enhancement in the same patient. For this individual, the 12-year comparison captured a transition from mild dysfunction and focal lateral-wall fibrosis to marked ventricular enlargement, impaired mechanics, reduced ejection fraction and extensive fibrosis.

Whether that pattern is typical, how early such changes emerge and how they should guide surveillance or treatment require evidence from larger longitudinal studies.

Subject of Research: Longitudinal cardiac MRI evidence of progressive myocardial involvement in Becker muscular dystrophy

Article Title: Case Report: Twelve-year longitudinal CMR follow-up in Becker muscular dystrophy–associated cardiomyopathy

Article References: Azmi, M. I., Takafuji, M., & Plein, S. (2026). Case Report: Twelve-year longitudinal CMR follow-up in Becker muscular dystrophy–associated cardiomyopathy. Frontiers in Medicine, 13, Article 1969565. https://doi.org/10.3389/fmed.2026.1969565

Image Credits: AI Generated

DOI: 10.3389/fmed.2026.1969565

Keywords: Becker muscular dystrophy, cardiac MRI, cardiomyopathy, myocardial fibrosis, late gadolinium enhancement, ventricular remodelling, left ventricular function, myocardial strain, T1 mapping, case report, Case, Report