Werner Irnich: Pioneer in the Development of the Dual‐Chamber Pacemaker—An Obituary

Fifty years ago, Werner Irnich presented the concept of an optimal pacemaker capable of responding appropriately to various cardiac arrhythmias and perceptual disturbances, and intended to be used in 85% of patients. With this concept, Irnich was far ahead of his time. His proposed circuitry for AV block and atrial fibrillation, as well as his suggestions for antitachycardia pacing and interference detection, were visionary. In the field of rate-adaptive pacing, he introduced AV-time control, the first closed-loop system. Werner Irnich represents the close connection between engineers and physicians in the field of cardiac electrotherapy. His theoretical work on the chronaxie rheobase and the electrode surface, confirmed by experimental data, still forms the basis of modern electrical stimulation today. The most extensive data on the interference immunity of electronic implants comes from his laboratory. In addition to his membership in numerous scientific societies, Werner Irnich served as Senior Editor of the international journal Pacing and Clinical Electrophysiology (PACE) from 1978 to 2013. He passed away on December 2, 2023, at the age of 89, leaving behind his wife Hanni, five children, and twelve grandchildren. We will always remember him with gratitude and deep appreciation for his contributions to cardiac electrostimulation.