Myocardial abscess due to Klebsiella pneumoniae complicating acute infarction.

A case is described in which Klebsiella pneumoniae urosepsis associated with acute myocardial infarction resulted in myocardial abscess and papillary muscle rupture. The diagnosis was made during surgery for mitral valve replacement. The patient improved after therapy with cefotaxime; however, cardiac rupture occurred on the sixth postoperative day. The pathogenesis of myocardial abscess and the use of non-invasive techniques for diagnosis are discussed.