Inclusion body myositis coexisting with hypertrophic cardiomyopathy: an autopsy study

Sporadic inclusion body myositis: no specific cardiac involvement in cardiac magnetic resonance tomography

Objective

To investigate cardiac involvement in patients with sporadic inclusion body myositis (IBM) by cardiac magnetic resonance tomography (CMR).

Methods

A case series of 20 patients with IBM underwent basic cardiac assessment and CMR including functional imaging, native and contrast-enhanced T1-weighted, and late gadolinium enhancement (LGE) imaging.

Results

All IBM patients reported no cardiac symptoms. Echocardiography was normal in 16/17 IBM patients. In CMR, IBM patients had normal ejection fractions (mean LVEF 63 ± 7%) and ventricular mass. They had reduced left (mean 55 versus 88 ml) and right ventricular stroke volumes (mean 54 versus 86 ml) and increased early myocardial enhancement (pathological T1 Ratio in 44% versus 5%), as compared to age- and gender-matched controls. Since arterial hypertension was more often observed in IBM patients, hypertensive heart disease can also be causative for these changes. Late gadolinium enhancement did not differ statistically from healthy controls. There was no apparent association between elevated biomarkers, echocardiography and CMR.

Conclusion

CMR revealed subtle changes in cardiac geometry and tissue characterization in IBM patients when compared to a gender- and age-matched control group. Findings in CMR indicated a higher extent of diffuse myocardial fibrosis as well as smaller left ventricular stroke volumes. These alterations may be due to a higher prevalence of arterial hypertension in the IBM cohort.

Sporadic inclusion body myositis: A review of recent clinical advances and current approaches to diagnosis and treatment

Sporadic inclusion body myositis is the most frequent acquired myopathy of middle and later life and is distinguished from other inflammatory myopathies by its selective pattern of muscle involvement and slowly progressive course, and by the combination of inflammatory and degenerative muscle pathology and multi-protein deposits in muscle tissue. This review summarises the findings of recent studies that provide a more complete picture of the clinical phenotype and natural history of the disease and its global prevalence and genetic predisposition. Current diagnostic criteria, including the role of electrophysiological and muscle imaging studies and the recently identified anti-5'-nucleotidase (anti-cN1A) antibody in diagnosis are also discussed as well as current trends in the treatment of the disease.

Emerging therapeutic options for sporadic inclusion body myositis

Sporadic inclusion body myositis is the most common inflammatory muscle disorder preferentially affecting males over the age of 40 years. Progressive muscle weakness of the finger flexors and quadriceps muscles results in loss of independence with activities of daily living and eventual wheelchair dependence. Initial signs of disease are often overlooked and can lead to mis- or delayed diagnosis. The underlying cause of disease is unknown, and disease progression appears refractory to available treatment options. This review discusses the clinical presentation of inclusion body myositis and the current efforts in diagnosis, and focuses on the current state of research for both nonpharmacological and pharmacological treatment options for this patient group.