Surgical treatment for chronic thromboembolic pulmonary hypertension: an historical perspective

Chronic thrombotic occlusion of the pulmonary arteries that results in pulmonary hypertension is now recognized as being relatively common, and surgical treatment of the condition is being increasingly applied throughout the world. However, the condition was not described until 90 years ago, and just 60 years ago less than 200 cases of the syndrome had been reported. At that time the condition was thought to be inoperable. Surgery for the acute phase of pulmonary embolism was attempted beginning 100 years ago, with minimal success until cardiopulmonary bypass was developed and could be used to stabilize the patient during induction of anesthesia and the surgical removal of the embolus. Pulmonary endarterectomy was suggested as a possible surgical approach to the chronic condition in 1956, and the first planned pulmonary endarterectomy was performed in 1957. Over the next thirty years several operations were attempted in Europe and the United States. By 1989 it is likely that fewer than 250 cases of pulmonary endarterectomy had been attempted, with a mortality rate of greater than 20%. Some cases of pulmonary endarterectomy had been carried out successfully at the University of California, San Diego (UCSD), beginning in 1970. The technique of the operation was refined, and in 2003 the results of 1,500 of these operations performed at UCSD were described, with a mortality rate of less than 5%. The good results obtained in San Diego encouraged other groups internationally to start their own programs and the operation is now well established, with good results. The following discourse traces the development of surgery, first for acute pulmonary embolism, and also, growing out of that experience, an operation for chronic pulmonary embolism.