Chronic myositis with cardiomyopathy and respiratory failure associated with mild form of organ-specific autoimmune diseases

The Risk of Ventricular Tachyarrhythmias in Patients with Antimitochondrial Antibodies-Related Noncardiac Diseases

Antimitochondrial antibodies (AMA) are serum autoantibodies specific to primary biliary cholangitis and are linked to myopathy and myocardial damage; however, the presence of AMA as a risk factor for ventricular tachyarrhythmias (VTs) has remained unknown. This study aimed to elucidate whether the presence of AMA-related noncardiac diseases indicates VTs risk.This cohort study enrolled 1,613 patients (883 females) who underwent AMA testing to assess noncardiac diseases. The incidence of VTs and supraventricular tachyarrhythmias (SVTs) from a year before the AMA testing to the last visit of the follow-up were retrospectively investigated as primary and secondary objectives. Using propensity score matching, we extracted AMA-negative patients whose covariates were matched to those of 152 AMA-positive patients. In this propensity score-matched cohort, the incidence of VTs and SVTs in the AMA-positive patients were compared with that in AMA-negative patients.The AMA-positive patients had higher estimated cumulative incidence (log-rank, P = 0.013) and prevalence (5.9% versus 0.7%, P = 0.020) of VTs than the AMA-negative patients. The presence of AMA was an independent risk factor for VTs (hazard ratio, 4.02; 95% CI, 1.44-20.01; P = 0.005). Meanwhile, AMA were associated with atrial flutter and atrial tachycardia development. In AMA-positive patients, VTs were associated with male sex, underlying myopathy, high creatine kinase levels, presence of chronic heart failure or ischemic heart disease, left ventricular dysfunction, presence of SVTs, and the electrocardiographic parameters indicating atrial disorders.The presence of AMA-related noncardiac diseases is an independent risk factor for VTs.

Myositis with Anti-mitochondrial Antibody Type 2 with Diplopia and Ptosis

Anti-mitochondrial antibody type 2 is a diagnostic marker of primary biliary cirrhosis and complicates myositis. Myositis with anti-mitochondrial antibody type 2 is clinically characterized by slowly progressive limb, cardiac, and respiratory muscle weakness as well as serum creatinine kinase elevations. However, there has been few cases with eye symptoms. We herein report a 59-year-old woman with anti-mitochondrial antibody type 2 who presented with diplopia and ptosis. Magnetic resonance imaging revealed bilateral ocular muscle enlargement and abnormally high intensities in the lower limb muscles. Corticosteroid therapy improved these symptoms. Myositis with anti-mitochondrial antibody type 2 can present with eye symptoms.

Muscle pathological features and extra-muscle involvement in idiopathic inflammatory myopathies with anti-mitochondrial antibody

OBJECTIVE

Anti-mitochondrial antibodies (AMAs) can be detected in some idiopathic inflammatory myopathy (IIM) patients. We aimed to investigate the clinical features of IIM patients with AMAs.

METHODS

We retrospectively analysed 1,167 consecutive patients with IIM for AMA-associated myositis and compared them to age- and gender-matched AMA-negative IIM patients.

RESULTS

Twenty-nine patients (2.5%) were identified with AMA-positive myositis; eight of them had primary biliary cholangitis (PBC). There were no significant differences in skin rash, dysphagia, interstitial lung disease, and muscle strength between AMA-positive patients and AMA-negative patients. Of 23 cases, 12 (52.2%) showed immune-mediated necrotizing myopathy (IMNM)-like pathological features. amongst AMA-positive patients, 11 of 16 patients with isolated anti-AMAs were classified as IMNM which was significantly higher than that of patients with coexistent anti-AMAs and myositis-specific antibodies (p = 0.026). Moreover, subclinical cardiac involvement was significantly more common in AMA-positive patients than in AMA-negative patients (21/29 VS 33/116, p<0.001). In addition, patients without PBC had a significantly higher incidence of abnormal echocardiography findings than that of patients with PBC (p = 0.009). Patients without heart abnormalities took significantly less time to achieve disease remission and prednisone tapering to <10 mg than patients with heart abnormalities (p = 0.000 and p = 0.001, respectively).

CONCLUSIONS

IMNM was a major histopathological finding in IIM patients with isolated AMAs. AMAs were significantly associated with subclinical cardiac involvement in IIM. PBC seemed to be a protective factor for abnormal echocardiography findings in AMA-positive patients. Patients without heart involvement took less time to achieve disease remission and prednisone tapering off.

Antimitochondrial Antibody-associated Myopathy with Slowly Progressive Cardiac Dysfunction

A 45-year-old woman was referred to our hospital for the evaluation of proximal muscle weakness and serum creatine kinase elevation [corrected]. She had atrial fibrillation and left ventricular asynergy. She was diagnosed with myopathy, accompanied by cardiomyopathy of unknown etiology. She was treated with prednisolone. After long-term follow-up and a detailed examination, the patient was diagnosed with antimitochondrial antibody (AMA)-associated myopathy with cardiac involvement. Although the patient received medical treatment, including beta-blockers and prednisolone, her cardiac function deteriorated progressively. Physicians should consider AMA-associated myopathy when diagnosing myopathies of unknown etiology. The presence of cardiac involvement should be proactively investigated in AMA-associated myopathy.

Cardiac involvement with anti-mitochondrial antibody-positive myositis mimicking cardiac sarcoidosis

Anti‐mitochondrial antibody (AMA)‐positive myositis is an atypical inflammatory myopathy characterized by chronic progressive respiratory muscle weakness, muscular atrophy, and cardiac involvement. Arrhythmias, cardiomyopathy, and myocarditis have been reported as cardiac manifestations. Herein, we present the first report of a patient diagnosed with having AMA‐positive myositis with cardiac involvement mimicking cardiac sarcoidosis.

Cardiac involvement in patients with primary biliary cholangitis: A 14-year longitudinal survey-based study

Patients with primary biliary cholangitis (PBC) can have extrahepatic manifestations. However, data about cardiac involvement of PBC is limited. We aimed in this study to analyze the clinical characteristics in patients with PBC complicated with and without cardiac involvement, and the risk factors of cardiac involvement in PBC. PBC patients admitted to Peking Union Medical College Hospital between January 2002 and February 2016 were consecutively enrolled. Structured interview, systemic rheumatologic examination, and laboratory tests were conducted for each patient, and risk factors of cardiac involvement were analyzed by comparing patients with and without cardiac involvement. In total, 580 PBC patients were enrolled, and cardiac involvement was identified in 24 patients (4%), with 11 male (46%) and a mean age of 57±8 year. Cardiomyopathy and arrhythmias were presented in 17 (70.8%) and 21 (87.5%) patients, respectively. Patients with cardiac involvement were more frequently male (46% vs. 11%, P<0.01), complicated with inflammatory myopathy (IM) (58% vs. 1%, P<0.01), and had a longer disease course (median, 72 vs 24 month, P<0.01). Furthermore, concomitant IM was the independent risk factor of cardiac involvement in PBC (OR = 77.333, 95% CI: 23.704–252.294). Cardiac involvement was a rare complication of PBC, which was more frequently observed in male or long-course patients. Importantly, concomitant IM was the strong independent risk factor of cardiac involvement in PBC. Given cardiac involvement is a serious complication, thorough evaluation of cardiac manifestation in high-risk PBC patients is highly recommended.

Inflammatory myopathy associated with anti-mitochondrial antibodies: A distinct phenotype with cardiac involvement

OBJECTIVE

In the context of clinical evaluations performed on our prospective myositis cohort, we noted a striking association of severe cardiac disease in myositis patients with anti-mitochondrial antibodies. We sought to review all cases of anti-mitochondrial antibody (AMA) associated myositis in our cohort to describe the clinical features of this disease subset.

METHODS

We identified 7 patients with confirmed anti-mitochondrial antibodies who presented as an inflammatory myopathy. A retrospective chart review was completed to assess their clinical presentation, laboratory, imaging, electrophysiologic, and histopathologic features.

RESULTS

One patient presented with dermatomyositis and 6 were classified as polymyositis using Bohan and Peter criteria. In all but one patient, a chronic course of muscle involvement was appreciated with an average of 6.5 years of weakness prior to presentation. Muscle atrophy was often noted, as well as atypical findings of scapular winging in 2 of the patients. Muscle biopsies were consistent with immune-mediated necrotizing myopathy in 4 patients, dermatomyositis in 1, polymyositis in 1 and nonspecific or granulomatous myositis in 1 patient. Changes pointing to mitochondrial alterations were seen in 2 of the 7 patients. Cardiac involvement (including myocarditis, atrial and ventricular arrhythmias, and cardiomyopathy), was seen in 5 out of 7 (71%) of the patients, and usually preceded the muscle involvement. Coexisting autoimmune conditions were seen in 3/7of the patients and included primary biliary cirrhosis, autoimmune hepatitis, psoriasis, and Hashimoto's thyroiditis.

CONCLUSIONS

Anti-mitochondrial antibodies identify a distinct inflammatory myopathy phenotype that is frequently associated with chronic skeletal muscle disease and severe cardiac involvement. Early recognition of this rare entity as an immune-mediated process is important due to implications for treatment. We propose that anti-mitochondrial antibody status should be determined in patients with a compatible clinical picture.

Antimitochondrial antibodies-positive myositis accompanied by cardiac involvement

We report a 55-year-old man who experienced proximal muscle weakness accompanied by the atrial flutter (AFL) with 1:1 conduction. Detailed examination revealed elevated antimitochondrial antibodies (AMA) and creatine kinase (CK). AFL was converted to sinus rhythm by cardioversion. He was diagnosed as AMA-positive myositis-associated AFL and was treated by prednisolone. Although his muscle weakness and CK level improved, AFL with 1:1 conduction reappeared. Therefore, radiofrequency catheter ablation (RFCA) was needed to treat the AFL, resulting in maintenance of sinus rhythm. This case report describes cardiac involvement in a patient with AMA-positive myositis.

Clinical values of FDG PET in polymyositis and dermatomyositis syndromes: imaging of skeletal muscle inflammation

OBJECTIVES

[(18)F] Fluorodeoxyglucose positron emission tomography (FDG PET), a standard tool for evaluating malignancies, can also detect inflammatory lesions. However, its usefulness in evaluating muscle lesions in polymyositis and dermatomyositis syndromes (PM/DM) has not been established.

METHODS

33 patients with PM/DM who had undergone FDG PET were retrospectively analysed. FDG uptake was visually evaluated (visually identified FDG uptake, vFDG) in 16 regions of the body using mediastinum blood vessels as a positivity criterion. We also calculated the maximum standardised uptake value (SUVmax) in all four limbs of the patients with PM/DM as well as in 22 patients with amyotrophic lateral sclerosis (ALS) with similar disabilities. In 24 patients with PM/DM, MRI and FDG PET findings were compared.

RESULTS

vFDG was observed in multiple muscle lesions with varying distributions in two-thirds of the patients with PM/DM, with most lesions being symmetrical. The number of vFDG-positive regions strongly correlated with the mean SUVmax in all four limbs (p<0.0001). Histological grades of biopsied muscles correlated with both the mean SUVmax and number of vFDG-positive regions. Serum creatine kinase levels were higher in patients with more than two vFDG-positive regions than in those with two or less regions (p<0.05). While the inflamed muscles showed diffused, patchy or marginal signal abnormalities on MRI, FDG uptake was most prominent inside the muscles. Compared with ALS, the mean SUVmax was significantly higher in the patients with PM/DM (p<0.0001) and showed a striking correlation in the bilateral muscles, reflecting symmetrical muscle involvement in PM/DM.

CONCLUSIONS

The visual assessment of FDG uptake as well as calculation of SUV enabled us to comprehensively evaluate skeletal muscle. This method can improve clinical practices and provide insights into pathomechanisms of PM/DM.