Right atrial thrombi complicating haemodialysis catheters. A meta-analysis of reported cases and a proposal of a management algorithm

Hemodialysis Tunneled Catheter Noninfectious Complications

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined.

Right atrial mural thrombi: An autopsy study of an under-diagnosed complication at an unusual site

Background:

Right atrial mural thrombi (RAMT) are often seen in association with cardiac diseases or foreign bodies. Unusual locations at the flutter isthmus and the atrial appendage prompted us to evaluate our 2-year autopsy data on such thrombi.

Materials and Methods:

In the 2-year retrospective autopsy, the clinical and autopsy records of patients with RAMT were reviewed, with particular reference to the presence of central venous catheter (CVC), its site of insertion, its type, material and size, its duration of placement, and the drugs infused through the catheter.

Results:

Of the 940 autopsies performed in 2 years, RAMT was seen in 24 hearts and was related to an insertion of a CVC in 23 patients (95.8%). The risk and/or associated factors for this complication were tunneled and polyethylene catheters, Intensive Care Unit admission, infused drugs, underlying cardiac diseases, and pregnancy. A noteworthy feature was the location of the thrombi in the flutter isthmus in 16 hearts (66.7%) and atrial appendage in another six hearts. Localized endocarditis/myocarditis and pulmonary thromboembolism were observed in six and four patients, respectively.

Conclusions:

This autopsy study, which has a high incidence of catheter-related RAMT, does not reflect the true incidence but reiterates the importance of guided insertion of central venous and prompt recognition of thrombus formation.

Ultrasound Assisted Catheter Directed Thrombolysis in the Management of a Right Atrial Thrombus: A New Weapon in the Armamentarium?

Catheter related thrombosis (CRT) is a commonly encountered entity fraught with substantial risk for mortality secondary to various complications including pulmonary embolism (PE), tricuspid regurgitation, endocarditis, right sided heart failure, and cardiogenic and septic shock. CRT carries a mortality rate of 18% in hemodialysis patients and more than 40% in nonhemodialysis patients. Management strategies include systemic anticoagulation, systemic thrombolysis, surgical evacuation, and percutaneous retrieval with no established guidelines. Ultrasound assisted catheter directed thrombolysis emerges as promising modality with a relatively lower risk of hemorrhage compared to systemic thrombolysis. We report a case of a 75-year-old man with dialysis catheter related thrombosis without PE for which ultrasound assisted catheter directed thrombolysis was used successfully as an alternative therapy.

Significance of Echocardiographically Detected Central Venous Catheter Tip-Associated Thrombi

PURPOSE

To explore significance, management, and outcomes of central venous catheter (CVC) tip-associated thrombi incidentally detected on echocardiography.

MATERIALS AND METHODS

Echocardiogram data from all patients with CVCs from October 2009 to June 2011 were reviewed (N = 170). Patients with CVC tip-associated thrombi were selected (n = 49). Echocardiograms were reviewed for ejection fraction, presence of patent foramen ovale (PFO), presence of other intracardiac shunts, and mean thrombus size. Management decisions, thrombus extension, pulmonary embolism, paradoxical emboli, and stroke within 3 months were recorded.

RESULTS

Mean thrombus size was 2.1 cm (range, 0.5-5.7 cm). Of patients with thrombi, 11 (22%) were already on anticoagulation, and there was no change in management. Anticoagulation was started without complications in 17 (35%) patients, the catheter was removed in 4 (8%) patients, and no new treatment was initiated in 17 (35%) patients. Of these 17 patients, 16 (94%) developed no complications. One (6%) patient with a PFO and right-to-left shunt experienced a stroke before PFO closure. After surgical closure of the PFO, the same patient developed catheter tip-associated thrombus without complication. There were no pulmonary emboli, strokes, or other detected embolic phenomena.

CONCLUSIONS

In this sample with CVC tip-associated thrombi but without PFO or other intracardiac shunts, no embolic or other complications were detected, regardless of anticoagulation status. These data suggest a benign course for such thrombi and that anticoagulation, catheter removal, thrombectomy, and thrombolysis may be unnecessary when catheter tip-associated thrombi are incidentally detected on echocardiography.

Catheter-Directed Low-Dose Tissue Plasminogen Activator for Treatment of Right Atrial Thrombus Caused by a Central Venous Catheter

Catheter-related atrial thrombosis is a potentially deadly complication of central venous catheters. Options for treatment include surgical thrombectomy, systemic anticoagulation, and systemic thrombolysis, but the optimal method of treatment remains unknown. We describe a 48-year-old woman with a large right atrial thrombus who was successfully treated with localized recombinant tissue plasminogen activator (tPA). She was treated with an 18-hour infusion of localized low-dose tPA administered through her central venous catheter. The dimensions of the thrombus decreased from 30 × 16 × 22 mm to 10 × 8 × 5 mm after treatment with tPA, corresponding to an associated 96% reduction in thrombus volume. No major bleeding complications were observed. Catheter-directed thrombolysis provides the theoretical advantage of a decreased rate of major bleeding by reducing the exposure to and duration of high-dose systemic thrombolytic therapy. To our knowledge, this is the second case report describing the use of this novel therapy. Although no guidelines for the treatment of atrial thrombosis or consensus on the optimal regimen for catheter-directed thrombolysis (and intensity of concomitant anticoagulation) exist, we believe that this intervention may be a well-tolerated alternative to systemic thrombolysis and surgery in certain patients.

The diagnosis of right heart thrombus by focused cardiac ultrasound in a critically ill patient in compensated shock

Right heart thrombus (RHT) is a life-threatening diagnosis that is rarely made in the emergency department (ED), but with the increasing use of focused cardiac ultrasound (FocUS), more of these cases may be identified in a timely fashion. We present a case of an ill-appearing patient who had an immediate change in management due to the visualization of RHT soon after arrival to the ED. The diagnosis was confirmed after a cardiology-performed ultrasound (US). This case illustrates the value of the recognition of RHT on FocUS and how US protocols designed for the evaluation of shock and shortness of breath may potentially be expanded to patients in a 'compensated' or 'pre-shock' state to expedite the correct diagnosis and to facilitate more timely management.

Catheter-related atrial thrombus: tip of the iceberg?

Although guidelines recommend catheters as a last resort for establishing a vascular access in patients undergoing dialysis, they continue to be used widely for this purpose. Catheter-related atrial thrombus (CRAT) is rarely reported in this group of patients, and it can lead to serious complications. The aim of this study was to determine the incidence of CRAT in patients undergoing hemodialysis with permanent-tunneled catheters. A total of 50 patients undergoing hemodialysis with permanent catheters were included in this study. The diagnosis of CRAT was based on transthoracic echocardiography findings. Thrombus was present in nine patients (18%) and related to the tip of the catheter in all cases. Except for one patient with two foci of thrombus, all patients had a single focus. There were no significant associations between the development of thrombus and the duration of catheter use or the location of the catheter. Furthermore, catheter-related atrial thrombus did not appear to have a significant effect on mortality. The asymptomatic character of CRAT can be responsible for the low reporting rates, and its exact role in increased mortality and morbidity related with catheter use remains unknown. While planning management strategies, information on different options for vascular access routes and possible catheter-related complications should be provided to all patients who will undergo dialysis, together with a discussion involving other replacement alternatives for end-stage renal disease.

American Society of Nephrology Quiz and Questionnaire 2013: RRT

The Nephrology Quiz and Questionnaire (NQ&Q) remains an extremely popular session for attendees of the Annual Meeting of the American Society of Nephrology. As in past years, the conference hall of the 2013 meeting was overflowing with interested audience members. Topics covered by expert discussants included electrolyte and acid-base disorders, glomerular disease, ESRD/dialysis, and transplantation. Complex cases representing each of these categories, along with single best answer questions, were prepared by a panel of experts. Before the meeting, program directors of United States nephrology training programs answered questions through an Internet-based questionnaire. A new addition to the NQ&Q was participation in the questionnaire by nephrology fellows. To review the process, members of the audience test their knowledge and judgment on a series of case-oriented questions prepared and discussed by experts. Their answers are compared in real time using audience response devices with the answers of nephrology fellows and training program directors. The correct and incorrect answers are then briefly discussed after the audience responses and the results of the questionnaire are displayed. This article recapitulates the session and reproduces its educational value for CJASN readers. Enjoy the clinical cases and expert discussions.

Right atrial thrombosis associated with hemodialysis catheter: first description of recurrence in a poorly understood problem

Catheter-related right atrial thrombosis (CRAT) is an underreported and potentially life-threatening complication of central venous catheter in hemodialysis patients. The accurate incidence is unknown, with reported rates ranging from 2 to 12.8% [1] in series, up to 29% [2] in a postmortem prospective study, and high mortality rates (18%) [1]. The optimal treatment for CRAT is controversial and nonsystematized, including anticoagulation, thrombolysis, and surgical thrombectomy. We report two cases of CRAT in dialysis patients, who underwent surgical thrombectomy. One case required reintervention because of recurrence, a first reported case in hemodialysis population.

Fatal pulmonary embolism after hemodialysis vascular access declotting

Patient: Male, 59

Final Diagnosis: Pulmonary embolism

Symptoms: Cardiac arrest • chest pain • dyspnea

Medication: —

Clinical Procedure: Angioplasty

Specialty: Nephrology

Cardiac thrombi in different clinical scenarios

Intracardiac thrombi are commonly found in patients with ischemic stroke. The echocardiographic identification of thrombi is important in decision-making since it represents an indication to long-term anticoagulation, in order to reduce the risk of new stroke. Intracardiac thrombi can develop during the time course of several cardiac pathologies that favor blood stasis and/or predispose to the aggregation of thrombotic material. Examples of cardiac pathologies that favor the formation of thrombus are illustrated and discussed.

Endocarditis Is a Common Stroke Mechanism in Hemodialysis Patients

Background and Purpose—

Hemodialysis patients are at high risk for ischemic stroke, and previous studies have noted a high rate of cardioembolism in this population. The aim of this study was to determine ischemic stroke causes among hemodialysis patients and elucidate specific cardioembolic stroke mechanisms.

Methods—

This study is a retrospective cross-sectional study of hemodialysis patients admitted with acute stroke to the University of Pennsylvania Health System between 2003 and 2010. Strokes were classified using modified Trial of Org 10 172 in Acute Stroke Treatment (TOAST) criteria as large vessel, cardioembolism, small vessel, atypical, multiple causes, or cryptogenic. Cardioembolic strokes were further characterized for specific mechanism.

Results—

We identified 52 patients hospitalized with acute stroke while receiving hemodialysis. Mean age was 64±13 years, 56% were female, and 67% were black. Stroke subtypes included 3 (6%) large vessel, 20 (38%) cardioembolism, 6 (11%) small vessel, 3 (6%) other, 4 (8%) with multiple causes, and 16 (31%) were unknown. Among patients who had an echocardiogram performed, 5 of 52 (10%; 95% confidence interval, 1%–18%) had a patent foramen ovale. Cardioembolic stroke mechanisms included 6 with infective endocarditis (accounting for 12% of all strokes).

Conclusions—

Cardioembolism and cryptogenic stroke are the predominant stroke mechanisms among hemodialysis patients. Infective endocarditis was identified frequently relative to other stroke cohorts, and a raised index of suspicion is warranted in the hemodialysis population.

Bilateral Pulmonary Emboli Secondary to Indwelling Hemodialysis Reliable Outflow Catheter

We present a 33-year-old dialysis-dependent female who presented with new onset split second heart sound. Following a failed left upper extremity dialysis fistula, a right upper extremity hemodialysis reliable outflow (HeRO) graft was performed in 2011. Her subsequent cadaveric renal transplant had delayed function necessitating concurrent use of hemodialysis. However, as renal function improved, hemodialysis was discontinued. Two weeks following transplantation, the HeRO graft occluded. Subsequent clinical and radiological assessment confirmed widespread pulmonary emboli. Following cessation of hemodialysis and subsequent HeRO graft occlusion, removal was deemed appropriate to reduce further thromboembolic phenomenon. Right atrial thrombi are complications associated with central venous catheters. However, their actual incidence varies significantly. Right heart thromboemboli are associated with a 4% to 6% pulmonary embolism rate. Katzman et al assessed 38 patients who underwent HeRO graft and reported 1 (2.6%) patient with right atrial emboli and likely pulmonary embolism. Although thrombotic complications remain rare, consideration of graft removal should always be evaluated particularly in the absence of an alternative thrombotic source.

Large right atrial thrombus associated with central venous catheter requiring open heart surgery

Central venous catheters (CVC) are used commonly in clinical practice. Incidences of CVC-related right atrial thrombosis (CRAT) are variable, but, when right atrial thrombus is present, it carries a mortality risk of 18% in hemodialysis patients and greater than 40% risk in nonhemodialysis patients. Different pathogenic mechanisms have been postulated for the development of CRAT, which includes mechanical irritation of the myocardial wall, propagation of intraluminal clot, hypercoagulability, and hemodynamics of right atria. Presentation of CRAT may be asymptomatic or may be associated with one of the complications of CRAT like pulmonary embolism, systemic embolism, infected thrombi, or hemodynamic compromise. There are no established treatment guidelines for CRAT. We describe an interesting case of a 59-year-old asymptomatic male successfully treated with open heart surgery after failure of medical treatment for a large CRAT discovered during a preoperative evaluation for a kidney transplant. Our case underscores that early detection of CRAT may carry a favorable prognosis as opposed to waiting until catastrophic complications arise. It also underscores the importance of transesophageal echocardiography in the detection of thrombus and perhaps guides clinicians on which treatment modality to be used according to the size of the thrombus.