A case of myasthenia gravis with cardiac fibrosis and easily provoked sustained ventricular tachycardia.

A 65-year-old male, who had been diagnosed to have myasthenia gravis (MG) 25 years previously, was admitted to our hospital with faintness. Cardiac ultrasonography showed decreased left ventricular function. Magnetic resonance imaging depicted delayed contrast enhancement in localized regions. No significant coronary artery stenosis was found, and due to the reproducible susceptibility for sustained ventricular tachycardia, he underwent cardioverter-defibrillator implantation. Although relatively uncommon, cardiac manifestations should not be overlooked in MG patients, as they may be associated with ventricular arrhythmias and cardiac dysfunction.