Seven hemodialysis patients with infected right atrial thrombi and/or tricuspid valve endocarditis are reported. All cases were attributed to use of tunneled venous catheters. Staphylococcus aureus was the preponderant organism isolated on blood culture. Therapeutic measures included antibiotics, catheter exchange, and surgery. One patient died with pulmonary embolism, and the remainder survived the infectious episodes. Experimental evidence further confirms the relationship of venous catheters placed in or proximate to the right atrium as the cause for the reported infected thrombotic and tricuspid valve complications. Measures to reduce the incidence of right heart complications must begin with recognition of the need for a surgically created arterial venous dialysis access placed early in the course of kidney disease. There is no entirely satisfactory method for prevention of venous catheter--induced endocarditis.