Mass lesions of the right atrium are usually detected by two-dimensional echocardiography. These are tumors, primary or metastatic, thrombi, vegetations, foreign bodies, such as pacemaker wires or obvious indwelling transvenous catheters. Artifacts produced by using high echocar-diographic gain settings, diaphramatic hernia, and ruptured sinus of Valsalva aneurysm may also mimic right atrial mass. We would like to add to the above list reservoir catheters (Mediport, Hickman, Omaya) in the superior vena cava and right atrium. These catheters are not easily detected because the implant sites are not obvious, and furthermore, they are not attached to external intravenous device.

Case Report
A 23-year-old white woman with a seven-year history of Hodgkin s disease was admitted with nausea, vomiting, fever, chills, palpitations, and syncope. She had a miscarriage 24 days prior to admission at five months’ gestation. Past medical history was significant for intravenous drug abuse, splenectomy, radiation, and chemotherapy. Physical examination on admission revealed temperature of 37.4°C, heart rate of 120 beats per minute, and blood pressure of 100/70 mm Hg. Lungs were clear to percussion and auscultation. Cardiac examination revealed normal heart sounds without murmurs or gallop. read more
Laboratory studies included a total white count of 10,900/cu mm with 74 percent polymorphonuclear leukocytes and 12 percent band cells. The hemoglobin level was 11.1 g/dl; LDH level, 288, SGOT value, 56; and alkaline phosphatase level, 111 IU/L. Blood cultures, urine cultures, and spinal fluid cultures were negative. The ECG and 24-hour Holter revealed sinus tachycardia. Chest x-ray film was within normal limits. Liver and lymph node biopsies showed no recurrence of Hodgkins disease. Ultrasound examination of the abdomen was normal. Echocardiography revealed a mobile, dense mass in the right atrium which was not attached to the tricuspid valve (Fig 1). In absence of a transvenous catheter or pacemaker, vegetation or a thrombus remained a clinical consideration. Angiography of the superior vena cava revealed an indwelling vascular catheter (Mediport) with the tip visualized in the right atrium. There were no mass lesions on the catheter, vena cava, or the right atrium. The patient, in retrospect, had a reservoir catheter implanted at age 16 for chemotherapy.
Her subsequent hospital course was unremarkable. As she was afebrile and multiple blood cultures were negative, she was not treated with antibiotics or surgery.
Discussion
Intracardiac catheters, such as pacemaker wires or cardiac segment of transvenous catheters, are usually recognized echocardiographically by increased echogenicity and mobility.4 Futhermore, a history of having such a procedure and an obvious site of implant helps in differentiating these from other mass lesions of the right atrium. In our patient, this was difficult to assess, as she did not remember having a catheter implanted, and the implant site in the right infraclavicular area was not visible on examination. The use of reservoir catheters for chemotherapy or antifungal therapy has increased, and consequently, this situation may be encountered more often. Like all foreign bodies, these catheters are prone to cause infections and may require surgical removal. In conclusion, reservoir transvenous catheters should be considered in the echocardiographic diagnosis of the right atrium mass lesions.

Figure 1. M-mode and two-dimensional (modified short axis view) echocardiogram of the patient depicting the right atrial mass (M). A is aorta; LA, left atrium; M, mass; RA, right atrium; RV, right ventricle.

Figure 1. M-mode and two-dimensional (modified short axis view) echocardiogram of the patient depicting the right atrial mass (M). A is aorta; LA, left atrium; M, mass; RA, right atrium; RV, right ventricle.