On December 29, 1863, cardiologist Wilhelm His Jr. was born in Basel, Switzerland. He was the son of a Swiss embryologist who constructed the first microtome, a tool that cuts extremely thin slices or sections of material for microscopic examination.
Why the heart beats was one of the great, unanswered questions in the 19th century. Bits and pieces of the puzzle were revealed as researchers built sequentially upon each finding. During medical research as an assistant physician, His Jr. applied the techniques taught him by his father and suggested them to his co-workers. He examined series of heart tissue sections to reveal that a connecting tissue developed into a bundle of fibres.
Dr. His Jr. described the specialized muscle fibre bundle that runs along the muscular partition between the left and right chambers of the heart. He characterized the fibres as the likely conductors of impulses that help synchronize the heart’s single rhythm of contraction. These fibres are now called the Bundle of His or the His Bundle. He was one of the first to recognize that the heart’s beat originates within the heart’s muscle cells.
In further cardiac study, His Jr. coined the phrase heart block to indicate faulty mechanism in heart contraction. His work added more pieces of cardiac knowledge and the questions he posed intrigued physiologists who followed.
Dr. His Jr. enjoyed a long clinical and teaching career, later specializing in joint diseases, and became Dean of Medicine, University of Berlin.
B Bondar / Real World Content Advantage