Perm-Cath catheter-related atrial thrombus – Case series and management recommendations

Prashanth Panduranga; Kumail Al-Lawatiya; Issa Al-Salmi; Baher Hanna

doi:10.4103/ACCJ.ACCJ_7_20

CASE REPORT

Year : 2020 | Volume : 2 | Issue : 1 | Page : 42-46

Perm-Cath catheter-related atrial thrombus – Case series and management recommendations

Prashanth Panduranga¹, Kumail Al-Lawatiya¹, Issa Al-Salmi², Baher Hanna²
¹ Department of Cardiology, Royal Hospital, Muscat, Sultanate of Oman
² Department of Nephrology, Royal Hospital, Muscat, Sultanate of Oman

Date of Submission	15-Apr-2020
Date of Acceptance	16-Apr-2020
Date of Web Publication	16-Jun-2020

Correspondence Address:
Dr. Prashanth Panduranga
Department of Cardiology, Royal Hospital, Post Box 1331, Muscat-111
Sultanate of Oman

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ACCJ.ACCJ_7_20

Abstract

Catheter-related atrial thrombus (CRAT) is frequent, with no clear guidelines available with regard to diagnosis and management. Here, we report five patients with Perm Cath related AT. We conclude and recommend that Perm Cath, when not needed or used needs to be removed as soon as possible. A majority of CRAT are detected incidentally. They commonly occur at inferior vena cava and right atrial junction and a transoesophageal echocardiogram is needed in most patients to clearly define the thrombus and see additional hidden thrombi. Differentiating CRAT versus vegetation is difficult and one needs to treat both if blood cultures are positive. Commonly these thrombi do not embolize and are fixed to atrial walls, but silent pulmonary embolism needs to be considered. All patients initially should be treated with intravenous or subcutaneous anticoagulation. Patients with “High Risk” features such as, “multiple thrombi > 2,” “mobile thrombi,” “extending or embolizing thrombi to pulmonary artery,” “infected thrombi,” and “failed anticoagulation” must be considered for thrombolysis followed by surgery if required.

Keywords: Anticoagulation, catheter-related atrial thrombus, echocardiogram, end-stage renal disease, hemodialysis, Perm Cath

How to cite this article:
Panduranga P, Al-Lawatiya K, Al-Salmi I, Hanna B. Perm-Cath catheter-related atrial thrombus – Case series and management recommendations. Ann Clin Cardiol 2020;2:42-6

How to cite this URL:
Panduranga P, Al-Lawatiya K, Al-Salmi I, Hanna B. Perm-Cath catheter-related atrial thrombus – Case series and management recommendations. Ann Clin Cardiol [serial online] 2020 [cited 2023 Mar 26];2:42-6. Available from: http://www.onlineacc.org/text.asp?2020/2/1/42/286475

Introduction

The use of tunneled central venous catheters for hemodialysis is wide but is associated with major clinical problems, such as thrombus formation, infections, and catheter dysfunction.^{[1],[2],[3],[4],[5]} Catheter-related atrial thrombus (CRAT) is a major concern in hemodialysis patients and can present as an incidental finding or with fever, shortness of breath, chest pain, or even sudden death due to pulmonary embolism.^{[6],[7],[8],[9],[10]} The diagnosis and management of CRAT is confusing, with no clear-cut guidelines available. We present five different case scenarios of tunneled central venous catheter, i.e., Perm Cath CRAT with different sizes of thrombi responding to different modalities of treatment followed by our recommendations.

Case Reports

Case 1

A 34-year-old female presented with the background of end-stage renal disease (ESRD) due to focal segmental glomerulosclerosis with history of living unrelated kidney transplant implanted in June 2003. In August 2012, she had graft failure with biopsy confirming IgA nephropathy and was managed conservatively. In May 2013, she was dialyzed using the right internal jugular vein (RIJV) Perm Cath. In November 2013, she was admitted with pneumonia, and routine transthoracic echocardiography (TTE) and then transoesophageal echocardiogram (TEE) showed a mass measuring 18 mm × 6 mm attached to right atrial (RA) free wall opposite to jet of Perm Cath suggestive of a thrombus, and hence, unfractionated intravenous heparin (UFH) infusion followed by warfarin was started with INR maintained between 2 and 3. Her blood cultures were negative. Subsequently, she traveled abroad to have another successful live unrelated kidney transplant in February 2014 (GFR, 85/min/1.73 m²). On follow-up, it was noted that her Perm Cath we present and a TTE and TOE showed 2 thrombi. Her INR was 2.3 on warfarin. One of them was measuring 12 mm × 5 mm at its maximum diameter and was attached to Perm Cath tip, whereas the other one was 16 mm × 9 mm and attached to the junction between inferior vena cava and RA [Figure 1]. The Perm Cath tip was noted deep in mid-RA. In view of persistent RA thrombus and appearance of new thrombus over Perm Cath on adequate anticoagulation, the Perm Cath was removed by pulling it out under aseptic condition with low risk of pulmonary embolism as the size were small and anticoagulation was given for three more months with complete resorption of thrombi.

Figure 1: Transoesophageal echocardiogram views: A small thrombus seen attached to the Perm Cath tip and another attached to the junction between inferior vena cava and right atrium, which regressed with anticoagulation therapy

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Case 2

A 70-year-old female with the background of diabetes with diabetic nephropathy (chronic kidney disease [CKD] Stage V on hemodialysis), hypertension, postcoronary artery bypass surgery (CABG), ischaemic cardiomyopathy (ejection fraction [EF] 20%), hypothyroidism, and bronchial asthma. She was dialyzed through the left brachio-cephalic arteriovenous fistula and then, distal radio-cephalic fistula. After the failure of these two fistulae, dialysis was carried out through RIJV Perm Cath since April 2013.

In December 2013, routine TTE showed a small mass suggestive of a thrombus noticed at Perm Cath tip and started on oral anticoagulation. In February 2014, she presented to our hospital with fever and rigors after a hemodialysis session. Blood cultures were taken through Perm Cath and peripherally. The centrally taken culture grew Streptophenomonas while the other three sets were sterile, hence not fulfilling Dukes criteria for endocarditis. TTE and TEE showed an echogenic mass measuring 10 mm × 6 mm attached to the catheter tip suggestive of a thrombus. There were no mobile masses attached to any valves. She was then started on UFH infusion, and the catheter removed after a week. Hemodialysis restarted after the insertion of a Femoral Perm Cath.

Repeated TEE after another week of UFH showed an increase in mass size despite source removal and aPTT twice the control. It was measuring 30 mm × 21 mm and attached to the junction between superior vena cava (SVC) and interatrial septum [Figure 2]. As she was deemed a high risk for open surgical thrombectomy, thrombolysis with Streptokinase given with repeated TEE showing the disappearance of this thrombus and a small residual clot measuring 5 mm in its maximum dimension. Anticoagulation with warfarin was recommenced and given for another 6 months with complete disappearance of the thrombus.

Figure 2: Transoesophageal echocardiogram views: Large thrombus attached to the intersection between superior vena cava and inter-atrial septum floating in right atrium

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Case 3

A 38-year-old man with the background of diabetes complicated by diabetic nephropathy and ESRD on hemodialysis started in February 2014. Since then, he had been dialyzed via RIJV Perm Cath. He presented with fever to his regional hospital in August 2014 and was thoroughly investigated. Despite negative initial blood cultures, he was treated with Tazocin and ceftriaxone empirically. His Permcath was removed as it was thought to be the source of fever, and the catheter tip grew Klebsiella sensitive to ciprofloxacin and Vancomycin, but the fever persisted. Then he was dialyzed through RFV catheter. Later, he was shifted to our institution where TTE and TEE showed three large masses in the right atrium, one at inferior vena cava (IVC)-RA junction measuring 25 mm × 15 mm with multiple fronds suggestive of a thrombus. Another mass was seen in the RA roof near SVC measuring 24 mm in its maximum diameter along with horizontally layered thrombus measuring 38 mm [Figure 3]. Moreover, small masses were seen attached to what looks like a remnant of the removed Perm Cath. He was treated with intravenous (IV) heparin for a week. Soon after, a computed tomography scan (CT) angiogram was performed, and it showed SVC thrombus in addition to right pulmonary artery (RPA) embolism with air bubbles suggestive of septic emboli and vegetations. Given multiple increasing thrombi with pulmonary embolism, he underwent surgery (atrial, IVC, SVC thrombectomy and pulmonary trunk, RPA thromboendarterectomy) successfully. The patient was treated as culture-negative endocarditis as well and discharged after completing 6 weeks of IV antibiotics. The histopathology showed thrombus, mixed inflammatory cell infiltrates, and areas of bacteria suggestive of infected thrombus. He was kept on warfarin for 6 months with echocardiogram at follow-up revealing complete thrombus resorption.

Figure 3: Transoesophageal echocardiogram views: (a), a large thrombus with fronds is seen at inferior vena cava and right atrial junction in a patient with Perm Cath. (b), another large thrombus at superior vena cava junction and a large layered thrombus at right atrial free wall and roof. Perm-Cath was removed earlier

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Case 4

A 37-year-old man, known case of hypertension, ESRD on hemodialysis and hepatitis B infection on treatment. Initially dialyzed by right femoral venous catheter, then in January 2013, RIJV Perm Cath was inserted. TTE in February 2013, done as a routine workup for renal transplant, showed three masses in the RA attached to the Perm Cath and RA free wall, largest being 32 mm × 28 mm in its maximum dimensions [Figure 4]. The masses were prolapsing to the tricuspid valve leaflets. The patient was started on unfractionated heparin anticoagulation and blood samples taken for culture as he spiked a fever. The cultures revealed the growth of Staphylococcus saccharolyticus, which was treated accordingly with antibiotics. It was then decided to operate on this patient as it was a large residual masses persisting. Cardiac surgeons requested a preoperative CT pulmonary angiogram, which showed evidence of silent bilateral peripheral pulmonary emboli with right lower lobe pulmonary artery thrombus as well. At surgery, a very large infected thrombus was seen filling the lower half of the RA and involving the coronary sinus and the entry of the IVC. It was organized and adherent to the atrial wall. The Perm Cath lumen was also thrombosed, and so it was cut high in the SVC and then removed. Then he was dialyzed through RFV with oral anticoagulation of 3 months with complete disappearance of thrombus.

Figure 4: Transthoracic echocardiography views: (a), a large thrombus is seen in right atrial in a patient with Perm Cath. (b), three thrombi noted occupying entire right atrial prolapsing into the tricuspid valve in the same patient

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Case 5

A 36-year-old man, diabetic, hypertensive, EF 20%, ESRD on hemodialysis via Perm Cath inserted December 2013. In March 2014, presented with fever with negative blood cultures and a TTE/TOE done showed very large mass suggestive of thrombus measuring 60 mm attached to Perm Cath prolapsing into RA. There was moderate pericardial effusion behind RA [Figure 5]. He was started on IV heparin therapy. In view of a very large thrombus, he was advised to open thrombectomy. A preoperative CT pulmonary angiogram showed segmental and subsegmental pulmonary embolism. However, he refused surgery, a repeat TTE after 3 weeks of oral warfarin therapy showed RA thrombus regression to 24 mm.

Figure 5: Transoesophageal echocardiogram views: A very large thrombus with fronds measuring >6 cm attached to Perm-Cath seen. There was sizeable pericardial effusion behind right atrial

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Discussion

Thrombosis is a very serious complication of tunneled central venous cannulation. The incidence is variable. The incidence of CRAT has been reported to be 18% in patients with tunneled hemodialysis catheters.^[8] There are two types of RA thrombi.^[11] Type A is found in anatomically normal atria and usually originates from deep venous thrombosis (DVT). They are characteristically mobile and are called “emboli in transit."^[12] This type of thrombi is associated with a high rate of pulmonary embolism and higher mortality. Type B consists of mural thrombi occurring either in the presence of a foreign body (like a central catheter) or a structurally abnormal atrium.^{[6],[7],[11],[12]} They are usually immobile and have a lower mortality rate. Perm-Cath related CRAT is most likely happening due to the constant irritation of the right atrium by the tip of the catheter with the blood jet hitting the IVC-RA junction.^[13] Deep RA tip placement causes trauma due to “to-and-fro” movement of the catheter tip during cardiac contractions along with “jet” injury from infusions.^[14] This irritation will cause endothelial injury with subsequent activation of the coagulation cascade and platelet aggregation. This is supported by several studies showing a higher incidence of CRAT when the tip is placed in the right atrium^{[4],[15],[16]} and is also seen in most of our patients. Glion et al., for example, found that the incidence can be as high as 46% compared to none when the tip is placed in the vena cava.^[16] Therefore, it is suggested that the best location is at the junction between SVC and right atrium.^[17] Other pathogenic factors include intraluminal thrombus propagation, hypercoagulability in HD patients, and fluid dynamics in the right atrium, with the catheter tip being located at the point of relative stagnation of blood flow.^[18],[19]

Patients with CRAT might be asymptomatic, being picked up incidentally while undergoing imaging for other reasons.^[6],[9] However, they might be suspected during hemodialysis when resistance to flow gets noticed. Moreover, symptoms resulting from complications may occur.^[6],[9],[10] If TTE failed to show any mass despite high clinical suspicion, then TEE should be done, especially in patients with device leads in the right atrium or ventricle.^[2],[3],[18]

Limitation of TEE is missing any thrombus when the catheter tip is proximal in SVC.^[18] Attention must be paid to differentiate thrombus from vegetation as most of these patients present with catheter-related bacteremia, as noted in our series.^[7],[10] Duke's criteria, if fulfilled will be helpful; otherwise, mass characteristics would give some clues. RA thrombus usually has a broad-based mural attachment.^[7] It can protrude into the RA cavity with less motion during the cardiac cycle. It can either be single or multiple, layered along RA free wall, or attached to Perm Cath tip. They can be multi-lobed or with fronds like extensions (as seen in one of our patients), but no masses can be seen in tricuspid valve leaflets in pure RA thrombus.^[7] In contrast, vegetations have an irregular surface, highly mobile, less echogenic, and can be found on valve leaflets. There is an association between CRAT and catheter-related septicemia.^[15],[20] The majority of the pathogens are either Gram-negative rods (such as Klebsiella pneumoniae) or Gram-positive cocci.^[20] If the nature of the mass is still questionable, either treating for both or considering cardiac CT/magnetic resonance imaging before treatment is a valid action depending on availability.^[21],[22]

The management strategy for CRAT is not well established as there are no prospective studies to answer this question, and many retrospective studies giving variable results. From older studies, mortality associated with CRAT has been reported to be 18% in HD patients and >40% in nonhemodialysis patients.^[6],[8] In general, there are three modalities of treatment, along with Perm Cath catheter removal: Anticoagulation, thrombolysis, and surgical thrombectomy.^{[6],[9],[23],[24],[25],[26],[27],[28]} Catheter removal before anticoagulation may lead to pulmonary embolism.^[4] Catheter removal after attaining therapeutic anticoagulation is the treatment in most of the cases with a diagnosis of CRAT.^[6] Mohan et al., in their study, showed that oral anticoagulation and thrombolysis appear to be the mainstay of treatment with surgery limited for selected patients.^[7] They concluded that oral anticoagulation remains to be the gold standard for mural thrombus with 91% success in dissolving the thrombus. Thrombolysis considered for indications such as pulmonary embolism, increased fragility and mobility of thrombus, and extension of thrombi into the left side across patent foramen ovale (PFO).^[7] They also concluded that thrombolytic therapy was best for thromboembolus while oral anticoagulation was enough for mural thrombus, and surgical embolectomy must be the last resort as it has a risk of delay, complications of cardiopulmonary bypass, and the inability to remove thrombus beyond the proximal pulmonary arteries.^[7]

Tran et al. reported in a retrospective study that primary treatment selection was anticoagulation in nearly 50% of patients, surgical thrombectomy in 25%, and thrombolysis in about 20% of patients.^[9] Treatment failure for anticoagulation and thrombolysis was about 30% each. In their series, the most common rescue therapy was surgical thrombectomy, ultimately, resulting in a total surgical rate of 40%. Overall, per-patient mortality was 20%. In another study, Yang et al. concluded that the treatment of CRAT with catheter exchange and repositioning within the right atrium combined with anticoagulation is an effective strategy for the treatment of CRAT in hemodialysis patients.^[29] If CRAT detected before renal transplant surgery, a study showed that usual treatment for CRAT needs to be started, and CRAT should not be a reason for delaying the transplantation.^[30] In a study, infective tunneled hemodialysis catheter-related RA thrombi resulted in mortality of 42% despite catheter removal and appropriate antibiotics.^[31] Earlier, it was thought that if the thrombus is >20 mm in size, an emergency surgical thrombectomy should be considered, along with catheter removal, to reduce the risk of infection, catheter dysfunction, or pulmonary embolism.^[6] A metanalysis suggested 6 cm as a cut-point size for surgical thrombectomy.^[6] However, in one of our patients >60 mm thrombus regressed with oral anticoagulation.

From Our Case Series and Based on Literature Review, We Recommend Following Strategy

First, patients should be categorized as “responders” or “nonresponders.” All patients with CRAT of any size should be given IV Heparin therapy or subcutaneous LMWH therapy for a week duration and repeat TTE/TEE after a week. If the size of the thrombus reduces by 50% whom we call “responders.” If size of the thrombus does not reduce by 50% or remains the same then it should be considered as “nonresponder” or “failed anticoagulation"
Second, the patient should be categorized as “high risk” or “low risk.” The “High Risk” features are, “multiple thrombi >,” “mobile thrombi,” “extending or embolizing thrombi to the pulmonary artery,” “infected thrombi” and “failed anticoagulation."
Third, for all size of thrombi if “low risk” after a week's treatment of IV/SC anticoagulation, catheter removal can be safely done followed by oral warfarin therapy with target INR of 2–3 for a period of 3–6 months
Fourth, if “high risk” features present irrespective of size of thrombus, after a week's treatment of anticoagulation with no response, consider thrombolysis preferably by streptokinase infusion rather than a bolus fibrinolytic dose as it has an inherent risk of acute pulmonary embolism. If thrombolysis fails then to consider surgical thrombectomy as in our case series as surgery is very high risk in these patients with other comorbid problems and cardiac surgeons are not happy to go ahead with surgery whenever large thrombi detected.

Conclusions

We conclude and recommend that Perm Cath, when not needed or used needs to be removed as soon as possible. Majority of CRAT are detected incidentally. They commonly occur at inferior vena cava, and RA junction and a transoesophageal echocardiogram is needed in most patients to clearly define the thrombus and see additional thrombi. Differentiating CRAT versus vegetation is difficult, and one needs to treat both if blood cultures are positive. Commonly these thrombi do not embolize and are fixed to atrial walls, but silent pulmonary embolism needs to be considered. All patients initially should be treated with IV/SC anticoagulation. Patients with “High Risk” features such as, “multiple thrombi >2,” “mobile thrombi,” “extending or embolizing thrombi to the pulmonary artery,” “infected thrombi” and “failed anticoagulation” must be considered for thrombolysis followed by surgery if required.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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