Antibodies against myosin in sera of patients with idiopathic paroxysmal atrial fibrillation.

Introduction: Circulating autoantibodies against myosin heavy chain have been detected in patients with ventricular myocarditis and in patients with dilated cardiomyopathy. This study investigated the presence of antibodies against myosin in sera of healthy control persons as compared with patients with idiopathic paroxysmal atrial fibrillation refractory to antiarrhythmic therapy.

Methods And Results: An SDS-PAGE (sodium dodecylsulfate polyacrylamide gel electrophoresis) procedure, followed by Western blotting with homogenates and membrane fractions of human left ventricular and atrial specimen as antigens, was used to analyze sera of 10 patients with idiopathic paroxysmal atrial fibrillation and 10 age-matched healthy control subjects.