:There's no "correct" ICD-9 code here, so it's silly to add one. Why would it be 429.4 rather than, say 999 (complication of surgical and medical care, not elsewhere classified, which includes complications of extracorporeal circulation)? It certainly doesn't seem to be "a febrile illness associated with pericardial and sometimes pleuropulmonary reaction that often follows extensive pericardiotomy (429.4)." A classification scheme that fails to distinguish between Dressler's syndrome and "pump head" is medically and pedigogically useless. This is a case in which the ICD-9 code (even if there were a "correct" one, rather than several which could be cobbled together) adds no useful information to the article. -