Transvenous pacing lead-induced thrombosis: a series of cases with a review of the literature

Now You See It, Now You Don't: Point-of-Care Ultrasound Identification of Left Ventricular Thrombus-in-Transit

BACKGROUND

Left-sided intracardiac thrombi are most commonly seen in conditions with decreased cardiac flow, such as myocardial infarction or atrial fibrillation. They can be propagated into the systemic circulation, leading to a cerebrovascular accident. Identification of thrombus-in-transit via point-of-care ultrasound (POCUS) has the potential to change patient management given its association with high patient morbidity and mortality.

CASE REPORT

An intubated 60-year-old man was transferred to our emergency department for management of altered mental status and seizure-like activity. The patient was markedly hypotensive on arrival, and cardiac POCUS was performed to identify potential causes of hypotension. A left ventricular thrombus-in-transit was identified. The thrombus was notably absent on a repeat POCUS examination < 10 min later, which led to concern for thrombus propagation. Furthermore, the patient's vasopressor requirements had significantly increased in that time period. Subsequent emergent neuroimaging revealed a large ischemic stroke in the left internal carotid and middle cerebral artery distribution. The patient was, unfortunately, deemed to not be a candidate for either thrombectomy or thrombolysis and ultimately expired in the hospital. Why Should an Emergency Physician Be Aware of This? Serial POCUS examinations identified the propagation of this patient's thrombus-in-transit, leading the physician to change the initial presumptive diagnosis and treatment course, and pursue further imaging and workup for ischemic stroke. Identification of a thrombus-in-transit is a clue to potentially underlying critical pathology and should be followed with serial POCUS examinations to assess for treatment efficacy and thrombus propagation.

Pacemaker-lead-associated thrombosis in dogs: a multicenter retrospective study

INTRODUCTION

Pacemaker implantation is the treatment of choice for clinically relevant bradyarrhythmias. Pacemaker-lead-associated thrombosis (PLAT) occurs in 23.0-45.0% of people with permanent transvenous pacemakers. Serious thromboembolic complications are reported in 0.6-3.5%. The incidence of PLAT in dogs is unknown.

ANIMALS, MATERIALS AND METHODS

multicenter retrospective study of seven centers with 606 client-owned dogs undergoing permanent pacemaker implantation between 2012 and 2019. 260 dogs with a transvenous pacemaker with echocardiographic follow-up, 268 dogs with a transvenous pacemaker without echocardiographic follow-up and 78 dogs with an epicardial pacemaker.

RESULTS

10.4% (27/260) of dogs with transvenous pacemakers and echocardiographic follow-up had PLAT identified. The median time to diagnosis was 175 days (6-1853 days). Pacemaker-lead-associated thrombosis was an incidental finding in 15/27 (55.6%) dogs. Of dogs with a urine protein:creatinine ratio measured at pacemaker implantation, dogs with PLAT were more likely to have proteinuria at pacemaker implantation vs. dogs without PLAT (6/6 (100.0%) vs. 21/52 (40.4%), P=0.007). Urine protein:creatinine ratio was measured in 12/27 (44.4%) dogs at PLAT diagnosis, with proteinuria identified in 10/12 (83.3%) dogs. Anti-thrombotic drugs were used following the identification of PLAT in 22/27 (81.5%) dogs. The thrombus resolved in 9/15 (60.0%) dogs in which follow-up echocardiography was performed. Dogs with PLAT had shorter survival times from implantation compared to those without PLAT (677 days [9-1988 days] vs. 1105 days [1-2661 days], P=0.003).

CONCLUSIONS

Pacemaker-lead-associated thrombosis is identified in 10.4% (27/260) of dogs following transvenous pacing, is associated with proteinuria, can cause significant morbidity, and is associated with reduced survival times.

Acute transvenous pacemaker lead thrombosis early after implantation: A rare clinical scenario

Symptomatic thrombus formation due to a permanent pacemaker (PM) lead is a rare complication. It could be associated with serious outcome and should be suspected in patients who present with unexplained right heart failure, dyspnea, or syncope following dual-chamber PM implantation. A timely decision to perform an echocardiographic examination, followed by medical, thrombolytic, or surgical treatment can be necessary. We describe the case of an 84-year-old man who presented with syncope and hypotension a few days after PM implantation. A transesophageal echocardiography revealed a mobile mass in the right atrium attached to the pacemaker lead. Intravenous heparin allowed a complete resolution of the thrombus.

Superior Vena Cava Syndrome from Pacemaker Leads in an Elderly Woman

Superior vena cava (SVC) syndrome is a constellation of clinical signs and symptoms secondary to obstruction of the SVC. The most common etiology is malignancy. However, the incidence of device-related SVC syndrome is increasing. The current management for device-related SVC syndrome includes open surgical intervention, endovascular repair, or systemic anticoagulation. We present a case of a 95-year-old female who developed SVC syndrome due to thrombosis secondary to pacemaker leads. She was treated conservatively due to her frailty and comorbid conditions. We discuss the evolving etiology of SVC syndrome, the most common presenting signs and symptoms, and a variety of potential treatments for non-malignant SVC syndrome. We also provide an example of when conservative management for chronic device-related SVC syndrome is appropriate.

Lead thrombus under standard-dose edoxaban in a patient with normal to high creatinine clearance and protein S deficiency

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) are as effective and safe as warfarin for thromboembolic prevention and treatment. The efficacy of NOACs lacks evidence from large and randomized studies in patients with inherited severe thrombophilia, including protein S deficiency. Further, some concerns still exist regarding the relative efficacy of edoxaban in preventing arterial thromboembolism in patients with normal to high creatinine clearance (CrCl). We present a case of a rare complication of lead thrombus under standard-dose edoxaban in a patient with protein S deficiency and supernormal renal function.

CASE PRESENTATION

A 65-year-old man experienced persistent chest tightness and a high level of D-dimer. Chest computed tomography (CT) showed a lead thrombus at the superior vena cava. He had a medical history including, paroxysmal atrial fibrillation (PAf), sick sinus syndrome after permanent pacemaker implantation, and transient ischemic attack. He received standard-dose edoxaban (60 mg daily) after PAf was diagnosed. His estimated CrCl was 98.6-102.1 mL/min. However, protein S deficiency (22.8%; normal range: 55-130%) was diagnosed. After switching to dabigatran (150 mg twice daily) for 3 months, the chest CT showed lead thrombus resolution and no symptoms were seen during the follow-up period.

CONCLUSIONS

This case was a rare complication of lead thrombus in a protein S deficient patient with normal renal function receiving standard-dose edoxaban. Edoxaban efficacy is uncertain in patients with protein S deficiency, and intracardiac devices also increase the risk of thromboembolic events.

Hybrid venous recanalization and cardiac implantable electronic device lead revision procedures: A single-center retrospective analysis of 38 patients

PURPOSE

The purpose of this study was to describe the safety and efficacy of hybrid recanalization procedures in a series of patients with obstructed central veins requiring cardiac implantable electronic device (CIED) revision.

METHODS

Between 2008 and 2016, 38 consecutive patients (24 M; age 60.5 ± 16.2 years; range 25-87 years) with central venous obstruction underwent 42 recanalization interventions performed in conjunction with CIED revision or extraction. Fifty percent of patients (19/38) presented with veno-occlusive symptoms, and 13% (5/38) of patients had CIED leads with an ipsilateral upper extremity dialysis conduit.

RESULTS

Ninety-one percent (38/42) of all procedures resulted in successful recanalization and CIED revision. Twenty-four percent (9/38) of all patients required secondary procedures due to recurrent stenosis, and 78% (7/9) of those requiring secondary procedures had indwelling dialysis conduits and/or clinical symptoms related to venous occlusion before the initial procedure. There were complications in 2 patients related to recanalization, and in 3 related to CIED revision.

CONCLUSIONS

Recanalization of central venous stenosis/occlusion in patients with CIED can be technically challenging but is successful in most patients. Symptomatic patients and those with dialysis conduits often require more aggressive revascularization interventions and may be at increased risk of complication or need for secondary interventions.

Pacemaker-associated thrombosis in ongoing therapy with edoxaban tosylate

Thromboembolism is a known complication of pacemaker implantation. However, published literature describes only a few cases, in which the events occurred in absence of antithrombotic prophylaxis, not routinely employed for its prevention in current clinical practice. We report a case of pacemaker lead-associated thrombosis in a patient taking continuative oral anticoagulant therapy with edoxaban tosylate (edoxaban). No data in present literature supports the use of anticoagulant prophylaxis for pacemaker lead thrombosis. In our report ongoing treatment with edoxaban proved ineffective for thrombosis prevention. We also discuss the role of three-dimensional transthoracic echocardiography for diagnostic assessment of thrombosis in a fragile patient.

Are Endovascular Interventions for Central Vein Obstructions due to Cardiac Implanted Electronic Devices Effective?

Objective: One of the late-onset complications of cardiac implanted electronic devices (CIEDs) is central venous obstruction (CVO). The aim of this study was to investigate the feasibility, efficacy, and safety of endovascular treatment of CIED-related CVOs.

Methods:Eighteen patients who underwent endovascular management of their device-related CVO were reviewed. Patients were classified into three groups: Group I patients were asymptomatic and needed lead replacement; Group II patients presented with symptomatic CVO without lead dysfunction, and Group III patients were referred with both symptomatic CVO and lead dysfunction. A treatment strategy involved recanalization and balloon angioplasty for Group I and angioplasty/stents for Groups II and III. Technical success, clinical success, complications, and long-term follow-up were assessed.

Results: Thirteen patients were in Group I, four in Group II, and one in Group III. Technical and clinical success was achieved in 17 patients (94%). No major complications were reported. Restenosis was observed in two patients at 40 and 42 weeks of follow-up, and these patients were successfully treated with angioplasty.

Conclusion: Endovascular management of CVO due to CIED is a safe and efficient technique. Plain balloon angioplasty is sufficient for lead replacement purposes, while stenting is needed for symptomatic CVO to achieve good long-term patency.

Endovascular delivery of leads and stentrodes and their applications to deep brain stimulation and neuromodulation: a review

Neuromodulation and deep brain stimulation (DBS) have been increasingly used in many neurological ailments, including essential tremor, Parkinson’s disease, epilepsy, and more. Yet for many patients and practitioners the desire to utilize these therapies is met with caution, given the need for craniotomy, lead insertion through brain parenchyma, and, at many times, bilateral invasive procedures. Currently endovascular therapy is a standard of care for emergency thrombectomy, aneurysm treatment, and other vascular malformation/occlusive disease of the cerebrum. Endovascular techniques and delivery catheters have advanced greatly in both their ability to safely reach remote brain locations and deliver devices. In this review the authors discuss minimally invasive endovascular delivery of devices and neural stimulating and recording from cortical and DBS targets via the neurovascular network.

Delayed right ventricular perforation complicated by intracardiac thrombosis after implantable cardioverter-defibrillator implantation

Cardiac perforation and intracardiac thrombosis are infrequent complications after implantable cardioverter‐defibrillator (ICD) implantation, and a case of lead perforation complicated by thrombosis is extremely rare. We report the case of a 66‐year‐old man with delayed ICD lead perforation concomitant with intracardiac lead thrombosis successfully treated by anticoagulant therapy followed by transvenous lead management.

Leadless pacing in a patient with superior vena cava syndrome undergoing lead extraction and percutaneous angioplasty

Superior vena cava (SVC) syndrome is an uncommon but serious complication associated with chronic transvenous implanted leads. In the recent past, open-heart surgery combining lead extraction and epicardial implant was usually performed to reduce syndrome recurrences. We describe the case of a 78-year-old man successfully treated by percutaneous lead extraction associated with venous balloon angioplasty and reimplantation of leadless pacemaker. <Learning objective: Chronic vascular complications following lead implantation usually require surgical treatment, due to the need for subsequent epicardial implantation. Percutaneous lead extraction along with leadless pacing allowed effective non-surgical management of chronic complications of transvenous pacing.>.

Permanent Cardiac Pacemaker: an Emergency Perspective

The number of patients with permanent pacemaker are increasing and may present into the emergency department with a variety of complications and malfunctions. The presence of a pacemaker may also affect management of unrelated medical issues. This article review the complications of the implant procedure, the causes, diagnosis and management of pacemaker malfunction, the pacemaker syndrome, Twiddler's syndrome. Interaction of permanent pacemaker with other medical condition and its implication in Emergency Department environment are also discussed.

Emergency Care of Patients with Pacemakers and Defibrillators

Devices such as pacemakers and implantable cardioverter-defibrillators (ICDs) are commonly inserted to treat unstable cardiac rhythm disturbances. Despite the benefits of these devices on mortality and morbidity rates, patients often present to the emergency department with complaints related to device insertion or malfunction. Emergency physicians must be able to rapidly identify potential life threats caused by pacemaker malfunction, ICD firing, and complications associated with implantation of the devices.

Fatal cardiac thromboembolism in a patient with a pacemaker during ureteroscopic lithotripsy for ureter stone: a case report

Intracardiac thrombosis is an infrequent and fatal complication in patients with an inserted pacemaker. A patient with an inserted pacemaker scheduled for ureter stone removal experienced cardiac arrest and cardiopulmonary resuscitation under general anesthesia. Echocardiography showed multiple intracardiac thrombi. Preoperative diagnostic workup including echocardiography for the detection of pacemaker lead thrombus, and the need for anticoagulation should be considered in patients with an inserted pacemaker and high-risk factors for thrombosis.

Surgical management of superior vena cava syndrome following pacemaker lead infection: a case report and review of the literature

Superior vena cava (SVC) syndrome is a known but rare complication of pacemaker lead implantation, accounting for approximately less than 0.5% of cases. Its pathophysiology is due to either infection or endothelial mechanical stress, causing inflammation and fibrosis leading to thrombosis, and therefore stenosis of the SVC. Due to the various risks including thrombo-embolic complications and the need to provide symptomatic relief, medical and surgical interventions are sought early. We present the case of a 48-year Caucasian male who presented with localised swelling and pain at the site of pacemaker implantation. Inflammatory markers were normal, but diagnostic imaging revealed three masses along the pacemaker lead passage. A surgical approach using cardiopulmonary bypass and circulatory arrest was used to remove the vegetations. Culture from the vegetations showed Staphylococcus epidermidis. The technique presented here allowed for safe and effective removal of both the thrombus and infected pacing leads, with excellent exposure and minimal post-procedure complications.

The Promise of Leadless Pacing: Based on Presentations at Nanostim Sponsored Symposium Held at the European Society of Cardiology Congress 2013, Amsterdam, The Netherlands, 2 September 2013

Pacemaker technologies have advanced dramatically over the decades since they were first introduced, and every year many thousands of new implants are performed worldwide. However, there continues to be a high incidence of acute and chronic complications, most of which are linked to the lead or the surgical pocket created to hold the device. A leadless pacemaker offers the possibility of bypassing these complications, but requires a catheter-based delivery system and a means of retrieval at the end of the device's life, as well as a way of repositioning to achieve satisfactory pacing thresholds and R waves, a communication system and low peak energy requirements. A completely self-contained leadless pacemaker has recently been developed, and its key characteristics are discussed, along with the results of an efficacy and safety trial in an animal model. The results of the LEADLESS study, the first human trial to look at safety and feasibility of the leadless device, are discussed and the possible implications for future clinical practice examined.

Echocardiography in patients with complications related to pacemakers and cardiac defibrillators

The evolving indications and uses for implantable cardiac devices have led to a significant increase in the number of implanted devices each year. Implantation of endocardial leads for permanent pacemakers and cardiac defibrillators can cause many delayed complications. Complications may be mechanical and related to the interaction of the device leads with the valves and endomyocardium, e.g., perforation, infection, and thrombosis, or due to the electrical pacing of the myocardium and conduction abnormalities, e.g., left ventricular dyssynchrony. Tricuspid regurgitation, another delayed complication in these patients, may be secondary to both mechanical and pacing effects of the device leads. Echocardiography plays an important role in the diagnosis of these device-related complications. Both two-dimensional transthoracic echocardiography and transesophageal echocardiography provide useful diagnostic information. Real time three-dimensional echocardiography is a novel technique that can further enhance the detection of lead-related complications.

One step behind to step ahead - femoral approach to stabilize and to extract functional pacing lead to regain venous access

Transvenous lead extraction can be a method to regain venous access. We present the case of a man, aged 67, with indications to upgrade an ICD to a resynchronization therapy device. Since innominate vein occlusion was diagnosed and extraction of an abandoned ventricular pacing lead did not provide lumen regain, a functional atrial lead was extracted with the femoral approach to stabilization and venous access was regained. Asymptomatic vein wall damage but no other complications were recorded. The simultaneous application of different techniques to regain venous access may allow success of the final procedure in system upgrading.

[Superior vena cava syndrome induced by pacemaker probes, 12 years after introduction]

Superior vena cava syndrome is a rare disease, most often found to result from a malignant process, which causes extrinsic compression of the superior vena cava. In recent years, there has been an increase of superior vena cava syndrome related to medical devices (implantable site, pacemaker [PM], central venous line for parenteral nutrition...). We report the case of a 37-year-old patient who developed a superior vena cava syndrome 12 years after implantation of a PM. The diagnosis was established on venography after two negative venous-CT focused on the superior vena cava. The superior vena cava syndrome improved immediately after angioplasty and stenting covering the PM probes at the superior vena cava/brachiocephalic venous trunk junction.

Relationship between changes in selected thrombotic and inflammatory factors, echocardiographic parameters and the incidence of venous thrombosis after pacemaker implantation based on our own observations

INTRODUCTION

Thrombosis (VTh) is a rare dangerous complication of pacemaker implantation (PM). The aim of the study was to determine the dynamics of change in selected thrombotic and inflammatory factors after PM.

MATERIAL AND METHODS

The study involved 81 patients (30 female, mean age: 71.1 years) with PM, divided into two groups. Group A (71 patients) consisted of patients without VTh, whereas group B (10 patients) comprised the patients with VTh. A transthoracic echocardiogram (TTE) and a venous ultrasound (VU) examination were performed. The levels of D-dimers, fibrinogen, tissue factor (TF), factor VII, plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) were determined in the venous blood. After PM, the TTE and VU examinations were repeated at 6 and 12 months, and blood analyses were performed within 7 days after PM, and subsequently at 6 and 12 months.

RESULTS

In 10 patients of group B, symptomatic VTh occurred at a mean time of 13.06 months after PM. Initially, the levels of IL-6, hsCRP, D-dimers, fibrinogen, TF, VII factor and PAI-1 were considerably higher in group B than in group A. In all patients the levels of these factors kept on increasing for up to 7 days after the procedure. In group A they subsequently decreased, whereas in group B they continued to rise.

CONCLUSIONS

Increased levels of inflammatory and thrombotic factors were observed in patients with VTh before and after PM. The factors of highest risk of VTh occurrence were D-dimers, fibrinogen and TF.

Diseases associated with thrombosis

Coagulation abnormalities are commonly encountered in critical illness. Traditionally, clinically relevant coagulation disorders have consisted mostly of bleeding associated with advanced stages of disseminated intravascular coagulation or toxin ingestion. However, advances in critical care have highlighted hypercoagulability as a clinically relevant state that must be recognized and treated to optimize the chances of a positive outcome. Retrospective studies of dogs with confirmed thrombosis in varying locations have identified populations most likely to experience hypercoagulable states. Diseases most frequently complicated by thrombosis include immune-mediated disease, neoplasia, systemic inflammation and sepsis, cardiac disease, protein-losing states, and infectious diseases. In this report, the existing retrospective studies will be discussed along with a review of specific disease processes that predispose to a hypercoagulable state. Studies targeting those populations most at risk for thrombotic complications are necessary for better understanding the need for prophylactic anticoagulant therapy.

Pacing device therapy in infants and children: a review

The number of pediatric pacemakers implanted is still relatively small. Children requiring pacing therapy have characteristics that are distinct from those of adults, including physical size, somatic growth, and cardiac anomalies. Considering these features, long-term follow-up of pediatric pacemaker implantation is necessary. Selection of appropriate generators, pacing modes, pacing sites, and leads is important. Generally, epicardial leads are commonly used in small infants. On the other hand, the use of endocardial leads in children is increasing worldwide because of their benefits over epicardial leads, such as minimal invasiveness, lower pacing threshold, and longer generator longevity. Endocardial leads are not suitable for patients with intracardiac shunts because of the high risk of systemic thrombosis. Venous occlusion is another significant problem with endocardial leads. With the increase in the number of pacing device implantations, the incidence of infection from such devices is also increasing. Complete device removal is sometimes recommended to treat device infection, but experience in the removal of endocardial leads in children is still scarce. This article gives an overview of pacing therapy in the pediatric population, including discussions on new pacing systems, such as remote monitoring systems, magnetic imaging compliant pacemaker systems, and leadless pacing devices.

Be aware of wires in the veins: a case of superior vena cava syndrome in a patient with permanent pacemaker

Superior vena cava (SVC) syndrome is an unusual complication of pacemaker and implantable cardioverter–defibrillator implantation. It is believed to be due to SVC thrombosis with or without stenosis induced by endothelial disruption from repeated mechanical trauma by the leads. A 58-year-old man presented with gradual swelling of his face, neck, and upper extremities of 10 days duration. A pacemaker had been implanted for symptomatic bradycardia over 5 years ago. Venous Doppler and venogram revealed thrombosis and stenosis of the SVC. He was treated with multimodal therapy and was discharged with complete resolution of his symptoms.

The first three-dimensional visualization of a thrombus in transit trapped between the leads of a permanent dual-chamber pacemaker: a case report

Introduction

Two-dimensional echocardiography is a useful tool in diagnosing cardiac masses. However, the three-dimensional offline reconstruction technique of transesophageal echocardiography might be superior to two-dimensional transesophageal echocardiography in providing additional information of structural details.

Case presentation

We report the case of a 76-year-old Caucasian man with a permanent dual-chamber pacemaker and a worm-like right-heart thrombus in transit. Two-dimensional transthoracic echocardiography and two-dimensional transesophageal echocardiography showed that it was debatable as to whether "the worm" was originating from the leads. Offline three-dimensional transesophageal echocardiography reconstruction technique proved superior in identifying the cardiac mass as a thrombus trapped between the leads of the pacemaker. The thrombus was successfully dissolved by systemic heparin therapy.

Conclusions

The three-dimensional transesophageal echocardiography is useful and effective in patients with implanted pacemakers or defibrillators when other closely competing imaging modalities are contraindicated, such as magnetic resonance imaging. In patients with pacemakers and trapped thrombus in transit for whom surgical therapy might be a high risk, medical therapy seems to offer a safer and convincing alternative. Whether the management of right-heart thrombi has to be modified due to the presence of pacemaker leads is controversial.

Right atrial thrombus secondary to pacemaker wires

BACKGROUND

Pacemaker-induced right atrial thrombus is a rare condition that has not been described in the Emergency Medicine literature. This is a potentially fatal condition that is diagnosed with an echocardiogram and treated with surgical removal, thrombolytics, or long-term anticoagulation.

OBJECTIVES

This case report is designed to increase awareness among emergency physicians of this potentially fatal condition.

CASE REPORT

We describe the case of a patient with a massive right atrial thrombus secondary to pacemaker wire who presented to the Emergency Department with syncope, bradycardia, and rapid hemodynamic deterioration.

CONCLUSION

Emergency physicians should be aware of this life-threatening entity. Emergency bedside cardiac ultrasound or echocardiogram may be of value in its early identification.

Cranial Vena Caval Thrombosis Associated With Endocardial Pacing Leads in Three Dogs

Three dogs were examined several years following implantation of transvenous, single-lead, endocardial, right-ventricular permanent pacing systems for signs consistent with cranial vena caval syndrome. Angiograms performed in all dogs revealed filling defects within the cranial vena cava and, in some instances, intracardiac filling defects. Medical therapy was instituted in two dogs, with one surviving several weeks. One dog underwent surgery to address intra-cardiac thrombosis but did not survive the immediate postoperative period. Postmortem examinations were performed in two dogs and confirmed cranial vena caval and intracardiac thrombosis. Cranial vena caval thrombosis associated with transvenous pacing leads appears to carry significant morbidity and mortality.

A case of the giant thrombus on atrial lead of a patient who has a DDD permanent pacemaker

We report a case of the giant thrombus on atrial lead of a patient who has a DDD dual-chamber permanent pacemaker.

Endovascular treatment of peripheral vascular disease

Peripheral arterial disease (PAD) affects about 27 million people in North America and Europe, accounting for up to 413,000 hospitalizations per year with 88,000 hospitalizations involving the lower extremities and 28,000 involving embolectomy or thrombectomy of lower limb arteries. Many patients are asymptomatic and, among symptomatic patients, atypical symptoms are more common than classic claudication. Peripheral arterial disease also correlates strongly with risk of major cardiovascular events, and patients with PAD have a high prevalence of coexistent coronary and cerebrovascular disease. Because the prevalence of PAD increases progressively with age, PAD is a growing clinical problem due to the increasingly aged population in the United States and other developed countries. Until recently, vascular surgical procedures were the only alternative to medical therapy in such patients. Today, endovascular practice, percutaneous transluminal angioplasty with or without stenting, is used far more frequently for all types of lower extremity occlusive lesions, reflecting the continuing advances in imaging techniques, angioplasty equipment, and endovascular expertise. The role of endovascular intervention in the treatment of limb-threatening ischemia is also expanding, and its promise of limb salvage and symptom relief with reduced morbidity and mortality makes percutaneous transluminal angioplasty/stenting an attractive alternative to surgery and, as most endovascular interventions are performed on an outpatient basis, hospital costs are cut considerably. In this monograph we discuss current endovascular intervention for treatment of occlusive PAD, aneurysmal arterial disease, and venous occlusive disease.

Two Cases of Silent Superior Vena Cava Syndrome associated with Vascular access and End-Stage Renal Disease

Due to the unavoidable use of indwelling devices and the magnitude of the operative problems encountered, Superior Vena Cava Syndrome (SVCS) has become a serious threat for patients with a history of multiple catheter placements. True diagnosis sometimes is not available due to paucity of symptoms or due to the inadequate considerations of the disease. Particularly in patients with chronic kidney disease, the evidence of central venous occlusion dictates the avoidance of placing peripheral dialysis access in this extremity. In this article, we report two patients (case 1- a patient with end stage renal disease and case 2 - a patient with chronic kidney disease) with silent SVCS related to stenosis resulting from indwelling pacemaker leads. Furthermore, the first patient had an extrinsic factor of compression, a brachial artery pseudoaneurysm - which although it was not causative - it may certainly have contributed to the development of SVCS. The brachial artery pseudoaneurysm restricted even more the flow to cephalic vein and consequently to superior vena cava. Though pacemaker leads have been well identified previously in the literature as a cause of the SVCS, the brachial artery pseudoaneurysm causing extrinsic compression constitutes a novel factor. Through the publication of this paper the awareness of SVCS in these patients shall be definitely enhanced. Moreover, physicians, nurses and patients shall be educated regarding the requirement for peripheral vein presentation in chronic kidney disease.

A case of pacing lead induced clinical superior vena cava syndrome: a case report

Introduction

Transvenous pacing is a relatively safe treatment with a low complication rate, but serious thromboembolic complications have been reported to occur in 0.6% to 3.5% of cases. Superior vena cava obstruction syndrome is generally an uncommon but serious complication occurring in <0.1% of patients. However, when it occurs it carries with it significant morbidity and mortality.

Case presentation

A 51-year-old lady with long history of DDD permanent pacemaker presented following a mechanical fall. She had no obvious injuries, and was hemodynamically stable. General examination revealed features suggestive of Superior vena caval obstruction which was later confirmed by imaging. She was treated with long term oral anticoagulation with good clinical improvement.

Conclusion

Superior vena cava obstruction in patients with transvenous pacing leads, although rare, is a well recognized complication. With growing elderly population and increasing number of procedures performed, more and more people with permanent pacemaker are likely to be encountered in clinical practice. One should carefully look for thromboembolic complications during follow-up in patients with transvenous pacemaker leads, as it has implications for future management and carries significant morbidity and mortality.

Right atrial pacemaker lead thrombosis causing tricuspid inflow obstruction

A 75-year-old man was admitted to our hospital with a complaint of progressive dyspnea with effort. The patient had a permanent pacemaker that was implanted 16 years ago. Transesophageal echocardiography revealed a large, mobile mass in the right atrium attaching to the insertion site of the atrial lead at the tricuspid valve level. Because of the size, mobility, and location of the mass, urgent surgical removal was considered. The mass was successfully removed. Histologic examination of the mass demonstrated a partially organized thrombus. The postoperative course was uneventful and the patient's symptoms improved remarkably after operation.

Right atrial thrombosis after upgrading to a biventricular pacing/defibrillation system

A 56-year-old man under right ventricular pacing for atrial fibrillation and bradycardia had congestive heart failure. He received a cardiac resynchronization pacemaker with a defibrillator. Four months later, follow-up transthoracic echocardiography showed a right atrial mass although he had no symptom. Transesophageal echocardiography showed a large immobile round-shaped mass on the defibrillation lead, which was attached to the free wall of the right atrium. One month after the initiation of anticoagulant therapy, the mass disappeared, suggesting that it was thrombotic. During the 5 month follow-up, he remained in good condition without the recurrence of right atrial thrombosis.