Alfred Lewis Galabin and the first human documentation of atrioventricular block

Using an apexcardiogram, Galabin was the first person to document atrioventricular (AV) block in humans. He performed his studies while working as a house officer at Guy’s Hospital, London, United Kingdom. His patient was 34 years old, experienced attacks of near syncope, and had a pulse rate that varied between 25 and 30 beats/min. A laddergram of the patient’s apexcardiogram suggests advanced AV block with 3 to 1 and 2 to 1 AV conduction with Wenckebach periodicity. We review the history of AV block beginning with the introduction of graphic recordings in 1847 by Ludwig, and include the contributions of Stannius, Luciani, Gaskell, Wenckebach, Hay, and Mobitz. Although he is little known today among cardiovascular physicians, we recognize Galabin as the first person to demonstrate AV block in humans.