Postmortem findings are presented in a case with acute pyelonephritis followed by an Escherichia coli and myocardial abscess and rupture of the left anterior papillary muscle. E. coll communis was cultured from heart blood, pericardial fluid, urine, spleen, lung and spinal fluid, and Gram-negative bacilli were demonstrated in the myocardial abscess. This is the first such case to be reported. Reference is made to a 2d case of abscess and rupture of the left anterior papillary muscle secondary to acute vegetative endocarditis.