In Memoriam: Gerhard Ziemer (1953-2022)

With sadness, we report the passing of a dear friend and colleague, Dr Gerhard Ziemer, a long-standing member of the Editorial Board of the World Journal for Pediatric and Congenital Heart Surgery and a respected member of the international congenital heart surgery community. His death came suddenly and unexpectedly in the early morning hours of November 11, 2022, at his home in Pennsylvania near the Geisinger Medical Center where he served as Director of Pediatric Cardiac Surgery & Adult Congenital Heart Surgery and Professor of Surgery and Pediatrics, Geisinger Commonwealth School of Medicine. Gerhard Ziemer studied medicine at the Christian-Albrecht University of Kiel, Germany, graduating in 1978. Immediately thereafter, he served as a medical officer in the German Navy, working in hyperbaric medicine. He went on to pursue training in general surgery, and then cardiothoracic and vascular surgery at Hannover Medical School (Medizinische Hochschule Hannover). Gerhard’s mentor, Professor Hans Borst, supported Gerhard’s interest in congenital heart surgery and encouraged him to pursue training in Boston with Professor Aldo Castaneda. Dr Ziemer spent three years at Boston Children’s Hospital, beginning as senior resident on Dr Castaneda’s service in 1984, then as a research fellow, and finally as chief resident. During his time in the laboratory, he worked closely with Dr Richard Jonas on studies of homograft, heterograft, and combined prosthetic and xenograft valved conduits in a variety of long-term intact animal circulatory models. Throughout this three-year period, Gerhard enthusiastically took in the wealth of knowledge that was made available to trainees through the regularly scheduled teaching sessions with Professors Richard Van Praagh and Stella Van Praagh, studying the amazing collection of specimens in the Cardiac Registry pathology laboratory. One of us (MLJ), having also been a resident at Boston Children’s Hospital in 1984, had the great pleasure of being scrubbed on a surgical case that Dr Ziemer was performing with the assistance and direct supervision of Dr Castaneda, while Professor Hans Borst observed over the ether screen during one of his visits to Boston. The reverence that Dr Ziemer had for these two mentors, Professors Borst and Castaneda, is something that Gerhard carried with him through the entirety of his career. Following the years at Boston Children’s Hospital, Dr Ziemer returned to Hannover, Germany, where he completed the Cardiovascular and Thoracic Residency, and joined the faculty, specializing in pediatric and congenital heart surgery. Dr Ziemer’s practice in Hannover grew steadily, and he quickly gained recognition for taking on challenging cases and achieving excellent outcomes. In 1987, he reported