Right atrial thrombus formation associated with central venous catheters utilization in hemodialysis patients

To report five patients on hemodialysis via an indwelling central venous catheter who developed a thrombus located exclusively on the right atrial wall opposing the emptying site of the superior vena cava and to determine the possible cause of this location.

Transthoracic echocardiography was performed in four of the patients as work-up for suspected endocarditis or pulmonary embolism and in one patient for syncope evaluation. The right atrial clots were confirmed in all the patients by transesophageal echocardiography.

General intensive care unit of a university hospital, tertiary referral center.

Five patients with end-stage chronic renal failure on hemodialysis via subclavian or internal jugular vein catheter.

Three of these patients underwent surgical thrombectomy, and two others were medically treated.

The clots were 2-4 cm in length and three of them were infected. Two of the three surgically treated patients and one of the two medically treated patients died. All the patients had the catheter tip in the right atrium, in two of them the bent catheter rubbed the atrial endocardium, and in all the cases the clot was located on the atrial free wall facing the superior vena cava emptying.

We postulate that the mechanism of thrombus formation at this location is related to friction of the catheter on the atrial endocardium, and therefore positioning the distal segment of the central venous catheters in the right atrium should be avoided.