Right Atrial Thrombi Complicating use of Central venous Catheters in Hemodialysis

Background

There has been an increase in the use of central venous catheters for temporary hemodialysis access. In this report, we describe a case series of 12 patients on hemodialysis who developed intracardiac clots associated with the use of central venous catheters, their outcomes and review the literature on this syndrome.

Methods

Retrospective, single-center case series of 12 patients with right atrial thrombi associated with central venous catheter use for dialysis vascular access. These patients were treated between June 1, 2001 and June 30th 2002 at the three University of Rochester affiliated dialysis clinics. The medical records of these patients were reviewed to obtain information concerning demographics, dialysis history, dates of catheter insertion, catheter complications, identification and dimensions of intracardiac thrombi, echocardiographic data, and outcome of anticoagulant therapy.

Results

Right heart thrombi were identified in 12 patients in our hemodialysis population over the study interval. Anticoagulation for 6 months led to clot resolution in more than 50% of our patients. Bacteremia recurred in 6 patients (50%), in spite of catheter replacement. There was zero mortality related to presence of clots in the short term. One patient with non-bacteremic right atrial thrombus suffered sudden cardiac arrest, but was successfully resuscitated.

Conclusion

Right atrial thrombi may occur in hemodialysis patients who use central venous catheters for dialysis access. These clots are frequently found in the right atrium or right atrial-superior vena caval junction. Ten of 12 patients (83%), had catheter-associated bacteremia, but the precise relationship between bacteremia and intracardiac clots is unclear. Chronic anticoagulation for 6 months lead to resolution of these clots in more than 50% of patients in our series.

Surgical Management of a Hemodialysis Catheter-Induced Right Atrial Thrombus

The placement of hemodialysis catheters are widely performed by vascular surgeons and surgical residents for use in both the hospital and the outpatient setting. Although long-term complications of this type of vascular access are relatively uncommon, an appreciation is warranted for the life-threatening complication of right atrial thrombus (RAT). Once recognized, medical or surgical management is mandatory to prevent further consequences from RAT. The optimal treatment for catheter-induced RAT is still controversial. Our case and review illustrates how the routine placement of a malpositioned hemodialysis catheter in a young man can lead to the serious complication of RAT that necessitated cardiac surgery after thrombolysis failed. We describe the successful surgical management of a hemodialysis catheter-induced RAT and suggest that in cases of large, mobile RATs with adherence to both atrial wall and catheter, suspicion or evidence of pulmonary embolus (PE), and low-risk surgical candidates, open thrombectomy may be an optimal and definitive treatment.

UNRESOLVED ISSUES IN DIALYSIS: Long-Term Management of the Tunneled Venous Catheter

Despite their propensity for significant complications, tunneled central venous catheters have become a common means of vascular access in the United States for patients requiring maintenance hemodialysis for end-stage renal disease (ESRD). Reasons for their use include advanced patient age, peripheral vascular disease (arterial and venous), late referral for creation of vascular access, and more importantly, the lack of an interdisciplinary service line on vascular access among vascular surgeons, radiologists, and nephrologists. This review article summarizes complications commonly encountered in dialysis patients who use tunneled central venous catheters for vascular access-mainly thrombosis, stenosis, and infection. Special attention is given to novel approaches for the prevention of catheter-associated infections. Effective prevention and timely treatment of common catheter-associated complications can reduce the substantial morbidity associated with the use of these devices. However, these measures should not detract from the goal of avoiding or limiting the long-term use of catheters, thereby optimizing vascular access management by ensuring the timely availability of functioning arteriovenous fistulas.

Right atrial thrombi complicating use of central venous catheters in hemodialysis

BACKGROUND

There has been an increase in the use of central venous catheters for temporary hemodialysis access. In this report, we describe a case series of 12 patients on hemodialysis who developed intracardiac clots associated with the use of central venous catheters, their outcomes and review the literature on this syndrome.

METHODS

Retrospective, single-center case series of 12 patients with right atrial thrombi associated with central venous catheter use for dialysis vascular access. These patients were treated between June 1, 2001 and June 30th 2002 at the three University of Rochester affiliated dialysis clinics. The medical records of these patients were reviewed to obtain information concerning demographics, dialysis history, dates of catheter insertion, catheter complications, identification and dimensions of intracardiac thrombi, echocardiographic data, and outcome of anticoagulant therapy.

RESULTS

Right heart thrombi were identified in 12 patients in our hemodialysis population over the study interval. Anticoagulation for 6 months led to clot resolution in more than 50% of our patients. Bacteremia recurred in 6 patients (50%), in spite of catheter replacement. There was zero mortality related to presence of clots in the short term. One patient with non-bacteremic right atrial thrombus suffered sudden cardiac arrest, but was successfully resuscitated.

CONCLUSION

Right atrial thrombi may occur in hemodialysis patients who use central venous catheters for dialysis access. These clots are frequently found in the right atrium or right atrial-superior vena caval junction. Ten of 12 patients (83%), had catheter-associated bacteremia, but the precise relationship between bacteremia and intracardiac clots is unclear. Chronic anticoagulation for 6 months lead to resolution of these clots in more than 50% of patients in our series.

Two cases of a free-floating ball thrombus in the left atrium

A free-floating ball thrombus in the left atrium is an unusual occurrence that may cause fatal systemic emboli or left ventricular inflow obstruction, often resulting in sudden death. The first of 2 cases was a 59-year-old female with mitral stenosis and chronic atrial fibrillation who presented with severe dyspnea. Transthoracic echocardiography revealed a free-floating ball thrombus and emergency thrombectomy and mitral valve replacement were performed successfully. A second thrombus, which was not found at preoperative examination, was attached to the anterior mitral leaflet and may have been the source of the free-floating ball thrombus. The second case was a 79-year-old female with chronic renal failure who underwent mitral valve replacement 11 years prior to admission. She had been dependent on hemodialysis for 10 years, and had suffered several recent transient cerebral ischemic attacks. Computed tomography showed a ring-shaped, high-density area in the left atrium and transthoracic echocardiography revealed a floating ball thrombus in the left atrium. Thrombectomy was performed, but the patient died as a result of postoperative pneumonia 2 months later. Case 2 appears to be the first reported case of a ball thrombus in a hemodialysis patient who had previously undergone mitral valve replacement.

Catheter thrombosis

Catheter malfunction due to poor flow is a common problem. When it occurs early, the cause is generally technical. Late occurrences are most often related to thrombus formation. Several types of thrombus may be seen, differing by location and supposed mechanism of formation. The most common offender, however, is the fibrin sheath thrombus. Prevention of catheter malfunction is an endeavor that continues to beg many questions. Catheter malfunction should be treated early to avoid inadequate dialysis. In the past, urokinase was a highly valuable aid to the nephrologist in managing this problem. Since this agent became unavailable a suitable alternative has not emerged. Recombinant tissue plasminogen activator (tPA) seems to be the most likely candidate for this role; however, it is not currently available in a packaging form that is optimal for this purpose. Currently, catheter exchange appears to be the best available alternative for this problem, which cannot yet be resolved by simpler means.

Atrial thrombus and central venous dialysis catheters

A native arteriovenous fistula is the first choice for hemodialysis access. Despite improved catheter designs and the use of internal jugular veins, thrombotic complications still occur when tunneled central venous catheters are used as an alternative. Although right atrial thrombus (RAT) is a well-characterized complication of long-term central venous cannulation, particularly when used for parenteral nutrition and chemotherapy in pediatric practice, only 9 reported cases previously have been associated with the long-term use of central venous catheters for hemodialysis. We report five cases of RAT seen at our unit between 1994 and 1998 in patients who had been dialyzed using tunneled catheters. In four of five cases, the diagnosis was made during the investigation of hemoptysis or dyspnea. In the fifth case, a screening transthoracic echocardiogram revealed the thrombus. Three of five of the patients suffered pulmonary emboli, and a fourth patient had an unexplained electromechanical dissociation cardiac arrest without definite evidence of pulmonary embolus. Our experience suggests that anticoagulated patients with RAT remain at risk of pulmonary embolism. One of our patients successfully underwent atrial thrombectomy. In four of five of our cases and four of nine cases in the literature, the central venous catheter tip was within the right atrium. Positioning of the central venous catheter tip low down in the superior vena cava or in the right atrium has been advocated to improve dialysis adequacy and to reduce the incidence of catheter thrombosis. However, placement of the catheter tip within the right atrium may be associated with an increased risk of RAT.

Right atrium thrombosis in patients on hemodialysis

Vascular access has been the Achilles heel of hemodialysis for many years, and placement of temporary subclavian and internal jugular vein catheters has been a daily practice for the nephrologist. Now, concern about central vein stenosis, well described with the use of subclavian catheters in end-stage renal disease (ESRD), has prompted the use of internal jugular vein permanent catheters to avoid this complication, so as not to hinder future arteriovenous grafts. Permanent catheter access is not without its own special problems, and we describe here two patients that developed thrombosis of the right atrium while receiving hemodialysis through a permanent internal jugular catheter.

Right atrial thrombus as a complication of subclavian vein catheterization--a case report

The author reports a case of right atrial ball thrombus in a patient with Behçet's disease who was receiving plasmaphoresis through a subclavian cathe ter and who had resolution of the thrombus while receiving heparin therapy.