title: Age, altitude, and arrhythmia.
abstract: Continuous electrocardiographic recording by Holter monitor was carried out during a climb to 5,895 m by an unacclimatized 65-year-old man confirmed to be without cardiac disease on rigorous examination. During ascent, marked ventricular ectopy and multiple runs of left ventricular bigeminy developed in association with an increase in P-wave amplitude of lead V2, and unchanged QT interval. With the diminished aerobic stress of descent, bigeminy disappeared, although premature ventricular complexes, apparently of right ventricular origin, remained increased throughout the climb. Arrhythmogenic mechanisms activated by prolonged exercise under hypoxic conditions are reviewed in relation to age.
authors.affiliation: Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA.
authors.forename: J K
authors.initials: JK
authors.lastname: Alexander
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D000531:Altitude; D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D015716:Electrocardiography, Ambulatory; D015444:Exercise / Q000502:physiology*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology; D008297:Male; D009051:Mountaineering / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000502:physiology
chemical_list: D018377:Neurotransmitter Agents