44-year-old woman was evaluated for the primary complaint of the
sensation of rapid and irregular beating of the heart, which was
intensified by exertion. This sensation had been apparent for
approximately 2 months and was associated with increased fatigability.
Her previous history disclosed that elsewhere, 21 years previously, she
had undergone aortic valve replacement combined with mitral valvotomy,
but the records of this event were unavailable. She had never
previously noted a rapid or irregular heart rhythm, and the remainder
of the history and review of systems was completely negative. Three
weeks previously, her referring physician had initiated regular oral
treatment with digoxin and warfarin.