Prosthetic Valve Thrombosis Presenting as an Acute Embolic Myocardial Infarction in a Pregnant Patient: Issues on Anticoagulation Regimens and Thrombolytic Therapy

Mechanical valves are inherently thrombogenic and require meticulous anticoagulation. Pregnancy produces a hypercoagulable state and achieving adequate anticoagulation is difficult. We present a pregnant patient who had a nonobstructive thrombus of mechanical mitral valve causing embolic acute myocardial infarction. Issues surrounding management of anticoagulation and use of thrombolytic therapy during pregnancy are discussed. Education regarding the critical nature of adequate anticoagulation in these patients is important.

Splenic embolus: 13 cases from a single medical department

BACKGROUND

Despite the spleen having a very rich blood supply, there is a paucity of reports of splenic emboli.

OBJECTIVES

To investigate the incidence of splenic emboli treated in a single general internal medicine department over the last 3 years.

METHODS

We examined the records of a 35 bed internal medicine department in a hospital in the center of Israel.

RESULTS

Over a period of 3 years 13 patients admitted to one internal medicine department developed acute abdominal pain and areas of hypoperfusion in the spleen on contrast computed tomography imaging. The patients were treated with anticoagulants, their course was benign and there were no long-term sequelae.

CONCLUSIONS

Embolus to the spleen is not rare in an internal medicine department. Diagnosis can be easily made by contrast CT scanning, and treatment with anticoagulants results in a good prognosis.

Percutaneous endovascular treatment of acute sequential systemic emboli

A 65-year-old woman was evaluated for acute right lower-extremity ischemia secondary to embolization from atrial fibrillation and subtherapeutic anticoagulation. Her symptoms quickly evolved in a dynamic fashion to involve multiple vascular beds, including a transient ischemic attack, abdominal pain secondary to mesenteric ischemia, and contralateral lower-extremity ischemia. Synchronous emboli were treated by using mechanical and pharmacologic thrombolysis via an endovascular approach under local anesthesia. This intervention allows prompt evaluation of multiple vascular beds with good short-term outcomes and minimal morbidity.

Direct aspiration using rapid-exchange and low-profile device for acute thrombo-embolic occlusion of the superior mesenteric artery

Acute thrombo-embolic occlusion of the superior mesenteric artery (SMA) is potentially fatal vascular emergency that requires rapid restoration of mesenteric blood flow as well as early diagnosis. Selective thrombolysis has been employed for this life-threatening event. Although failed thrombolysis is a well known phenomenon, which is directly connected with bowel necrosis, emergent laparotomy, and patient death, little progress has been made in its treatment strategy. Recently, direct aspiration using rapid-exchange and low-profile aspiration device has been reported as a simple, safe, and effective strategy to thrombus in coronary artery. We describe the utility of direct aspiration using this sort of aspiration device for failed thrombolysis of SMA thrombo-embolism.

Venous thromboembolic prophylaxis after elective total hip arthroplasty

Elective total hip arthroplasty is a common orthopaedic procedure that has been proven to relieve pain and reliably improves the quality of life of its patients. However, patients having a total hip arthroplasty are among those at greatest risk for venous thromboembolic disease. Therefore, most orthopaedic surgeons use routine prophylaxis. Although several agents have been shown to reduce the risk of thromboembolic disease, there is no clear preference for a particular agent in elective total hip arthroplasty. This evidence-based review focuses on the efficacy and safety of the agents that currently are used for prophylaxis against deep venous thrombosis. These agents include warfarin, low-molecular-weight heparin, fondaparinux, aspirin, and mechanical devices. Furthermore, the influence of shorter hospital stays on duration of prophylaxis and screening will be discussed. The most effective prophylactic agents for patients after total hip arthroplasty include low-molecular-weight heparin, warfarin, and fondaparinux. Pneumatic compression devices have been proven to reduce distal thromboembolic events but multi-center, randomized studies need to be done to determine the efficacy of mechanical prophylaxis with short hospital stays. The selection of a prophylaxis regimen is a balance between efficacy and safety, and individual patient factors can influence the prophylaxis regimen that is used.

Do complaints of amaurosis fugax and blurred vision after transcatheter device closure of atrial septal defect indicate microemboli to retinal vessels?

Atrial septal defect (ASD) is a common diagnosis in adults undergoing surgical repair. The aim of the study was to determine if ocular symptoms following treatment are due to microemboli. The study group included 20 adult patients (9 men, 11 women, mean age 57.2 years) with ASD who had undergone successful closure with the Amplatzer occluder. Patients were treated with aspirin or warfarin during the 6 months after the procedure. All were evaluated neurologically and an ocular medical history was obtained. Ocular examination included the 120-point Humphery visual field. Transcranial Doppler (TCD) was performed to monitor the middle cerebral artery. Two patients complained of amaurosis fugax at 1 and 3 months after the procedure, and two patients complained of blurred vision at 3 and 4 months after the procedure. TCD performed within 24 h of the complaints revealed no abnormalities. In all patients, the neurological and ocular examinations, including the visual field test, were normal. In conclusion, microembolic events do not appear to be the cause of the ocular complaints in patients with ASD treated with Amplatzer occluder. Further studies in larger samples are needed to confirm these results.

Fibrocartilaginous embolism in a chondrodystrophoid breed dog

An 8-year-old intact male Shih Tzu dog was admitted with acute-onset tetraplegia. Magnetic resonance imaging showed an abnormality of the cervical intramedullary spinal cord. Histopathological examination of a spinal biopsy confirmed the presence of intravascular cartilaginous emboli. This is the first report of an antemortem diagnosis of fibrocartilaginous embolism in a chondrodystrophoid breed dog.

Embolic cilioretinal artery occlusion due to carotid artery dissection

PURPOSE

To report a case of embolic cilioretinal artery occlusion caused by carotid artery dissection.

DESIGN

Interventional case report.

METHODS

A 38-year-old woman presented with acute visual loss in her right eye. Funduscopy showed a cilioretinal artery occlusion, which was confirmed by a fluorescein angiography. An embolus was found in the distal segment of the vessel.

RESULTS

Color Doppler images of right internal carotid artery (ICA) disclosed a pseudolumen, suggesting a diagnosis of carotid dissection. Retrobulbar color Doppler image showed relative low flow velocity in the ophthalmic artery without flow reversal. Magnetic resonance angiography and cerebral angiogram showed total occlusion of the right ICA. Follow-up visual field examination revealed an inferior central defect fed by the cilioretinal artery.

CONCLUSION

The pathogenesis of retinal artery occlusion caused by carotid dissection may be embolic or hemodynamic. In our case, a permanent visual defect was related to embolic occlusion of the cilioretinal artery.

Surgical therapy for acute superior mesenteric artery embolism

BACKGROUND

Acute mesenteric artery embolism has a high rate of morbidity and mortality. Early diagnosis and appropriate treatment are the most important factors associated with morbidity and mortality.

METHODS

During the period between 1997 and 2002, 24 patients underwent superior mesenteric artery embolectomy. The patients were divided into three groups according to the onset of symptoms and operation time. Group I (n = 12) patients were operated on in the first 6 hours after onset of symptoms; group II (n = 9) patients were operated on between 6 and 12 hours after onset; and group III (n = 3) patients underwent embolectomy after 12 hours. Low-dose (5 to 10 mg) local tissue-type plasminogen activator (t-PA) administration directly into the superior mesenteric artery was an additional procedure with the embolectomy in all patients.

RESULTS

The macroscopic view of the intestine was normal in 15 patients (12 patients in group I and 3 patients in group II) 30 minutes after the administration of local t-PA. Segmental resection was necessary in 4 patients in group II. Extended resection was necessary in 2 patients in group II and 3 patients in group III, and all of the patients died during the early postoperative period.

CONCLUSIONS

We suggest that explorative laparotomy should be done in patients with sudden abdominal pain, nausea, vomiting, mild leukocytosis, and metabolic acidosis who have previous valvular heart disease or atrial fibrillation. Ultimately, selective low dose t-PA (5 to 10 mg) administration reduces the length of intestinal portion to be resected.

Popliteal artery disease: diagnosis and treatment

The popliteal artery is a relatively short vascular segment but is affected by a unique set of pathologic conditions. These conditions, which may be common throughout the arterial system or exclusive to the popliteal artery, include atherosclerosis, popliteal artery aneurysm, arterial embolus, trauma, popliteal artery entrapment syndrome, and cystic adventitial disease. The clinical manifestations, imaging appearances, and treatment options associated with these pathologic conditions differ significantly. Consequently, the radiologist should be familiar with these conditions to direct imaging for accurate diagnosis and treatment and to prevent loss of limb.

FIBROCARTILAGINOUS EMBOLIC MYELOPATHY IN A SUMATRAN TIGER (PANTHERA TIGRIS SUMATRAE)

An adult, captive-born Sumatran tiger (Panthera tigris sumatrae) had been ataxic for approximately 3 mo and had been self-mutilating after an acute onset of unilateral paresis and Homer's syndrome. Histologic lesions in the cervical spinal cord were consistent with fibrocartilaginous embolic myelopathy (FCEM), and they included the presence of cartilaginous occlusion of spinal blood vessels. This is the first reported case of FCEM in a large felid and specifically a Sumatran tiger.

Modern aspects of antithrombotic treatment: an introduction

Intracardiac thrombosis and cardioembolisms may have impressive effects on quality of life, prognosis and therapeutic costs in patients with valve disease or replacement devices. Distinct pathophysiological differences exist regarding intracardiac thrombus formation in low-versus high-pressure areas. Important cardiac confounders for low-pressure areas are left atrial geometry and function, including atrial fibrillation or loss of active atrial contraction. In high-pressure areas, flow velocity and shear stress are raised, and this may result in flow turbulence, for example when blood passes a stenotic area. Other major factors which correlate with intracardiac thrombus formation are implantation of polymer material and the degree of endocardial damage resulting for example, from infective or rheumatic endocarditis. Because of the interaction of platelets and the plasma clotting system, a combination of oral anticoagulation therapy and antiplatelet drugs should prevent more thromboembolic events than might anticoagulation alone. Recent studies in patients with prosthetic heart valves have indicated a positive risk-benefit profile if low-dose antiplatelet drugs are added to moderate intensive oral anticoagulation therapy. Thromboembolic events and bleeding complications due to oral anticoagulation therapy are accepted key parameters to demonstrate the superiority of one replacement device over another. However, there is no consistent system for reporting morbid events. In order to organize low and narrow target INR ranges, point-of-care patient self-testing modalities have been introduced and used effectively in large sample sizes. In the near future, some promising new drugs--including direct thrombin or factor Xa inhibitors with broader therapeutic ranges and thus fewer side effects--will become available. The test for these drugs will be their potential to prevent intracardiac thrombosis and cardioembolism in a patient population which is under significant risk.

[Local lysis with alteplase for the treatment of acute embolic leg ischemia following the use of the duett closure device: preliminary results]

PURPOSE

To analyze retrospectively the result of the alteplase lysis therapy of embolic complications following the use of the Duett closure device.

METHODS AND MATERIALS

For 3.5 years, the Duett closure device was used in 1,398 angiographies to close the femoral puncture site. The Duett device consists of a balloon and a liquid procoagulant containing collagen and thrombin, which is injected into the puncture tract under endovascular balloon protection of the arterial puncture site. In 9 patients (0.64 %), the procoagulant was incidentally injected into the femoral artery causing acute leg ischemia. Eight patients received local lysis therapy with alteplase via a contralateral femoral access. One patient underwent surgery. On average, 21 mg alteplase (4 - 35 mg) were administered within 14 h (4 - 21 h). The course of the lysis was followed angiographically and clinically. All patients were interviewed by telephone 23 months (4 - 35 months) later.

RESULTS

In 3 patients, lysis was complete. In 5 patients, only little thrombotic material remained. In all patients, symptoms of ischemia resolved completely within the first hours after initiation of lysis. In 5 cases, bleeding occurred at the puncture site closed with the Duett device during lysis, including development of a false aneurysm in 2 cases. Complications led to premature termination (n = 2) or interruption of the lysis (n = 3). All complications were treated conservatively. Clinically, long-term sequelae were paresthesia and hypoesthesia in the lower leg and foot in 2 patients treated with lysis, and in the patient who underwent surgery.

CONCLUSION

Very rarely occurring embolic complications after use of the Duett closure device can be effectively treated with alteplase lysis. A high rate of complications is to be expected at the puncture site closed with the Duett device.

[True isolated atherosclerotic aneurysm of the axillary artery]

The true atherosclerotic aneurysm of the axillary artery is a rare condition. It either presents as a pulsatile axillary mass or arterial emboli in the hand and fingers. We report the case of a 70-year-old man with a 5 cm aneurysm of the axillary artery presenting with embolic disease to the hand. Angiography is helpful and provides valuable preoperative anatomic details. Surgery remains the treatment of choice but endovascular treatment can also be considered.

Superior mesenteric arterial embolism: a retrospective study of local thrombolytic treatment with urokinase in West China

Embolism of the superior mesenteric artery (SMA) is a rare disorder. To explore the selective criteria of local thrombolysis, evaluate its efficacy and discuss the therapeutic protocol of SMA embolism, a retrospective case control study was undertaken. Sixteen cases were divided into two groups: nine cases (group A) from May 1995 to April 1999 were given traditional treatment, while seven cases (group B) from November 1999 to June 2002 received comprehensive therapy including local thrombolysis. The local thrombolytic treatment was performed without procedure-related complications and the embolus was successfully lysed in four patients. The time between admission and diagnosis (or treatment) was shorter in group B than in group A (2.3 +/- 1.2 vs 12.3 +/- 9.2 hr, p = 0.013). Gangrenous bowel segments in group A were much longer than in group B (159.4 +/- 87.7 vs 45.7 +/- 61.6 cm, p = 0.009). However, mortality between the two groups was the same (p = 0.282, OR = 0.32, 95% CI = 0.039, 2.618) perhaps because of the small sample size. Angiography could shorten the duration from the onset of SMA embolism to therapy and certainly lowers the risk of mortality. Local fibrinolytic infusion may be an effective alternative to embolectomy in patients with SMA embolism but without intestinal infarction.

Acute branch retinal arterial embolism successfully treated with intravenous prostaglandin E1--case reports

The purpose of this paper is to report the use of intravenous prostaglandin E1, a potent vasodilator, to rapidly restore blood flow and vision in a patient with an acute branch retinal arterial occlusion. An 82-year-old woman with an acute decrease in the visual acuity of her left eye due to an acute superior temporal branch retinal arterial embolus was treated with 140 microg of intravenous prostaglandin E1. The medicine was repeated the following day. At the onset of the branch arterial occlusion her vision in the left eye was 20/50, the embolus could be seen in the superior temporal branch, and a white retinal edema extended down into the macula. At her first eye examination 4 days after treatment, her visual acuity had returned to 20/20, the retinal embolus was still present, but the white macular edema had disappeared. Intravenous prostaglandin E1 is a safe, potent vasodilator for the peripheral vascular system. If used immediately to treat acute branch arterial retinal occlusions, it can restore good vision. The authors report the first case of the use of intravenous prostaglandin E1 to treat a spontaneous acute branch retinal arterial embolus.

Cardiac sources of embolism should be routinely screened in ischemic colitis

OBJECTIVE

Potential cardiac sources of embolism may promote ischemic colitis. The aim of this study was to evaluate their role in segmental, nongangrenous ischemic colitis and to determine the usefulness of routine cardiac evaluation in patients with this disease.

METHODS

Sixty case and 60 control patients matched for age and gender were included and questioned regarding treatment and prior cardiovascular history or risk factors. Potential cardiac sources of embolism, classified as "proven" or " still debated," were screened using an electrocardiogram, rhythmic Holter monitoring over 24 h, and transthoracic echocardiography.

RESULTS

Sex ratio (male:female) was 1:2, and mean age was 70 +/- 14 yr. Case and control patients had similar drug use, prior cardiovascular history, and risk factors. A potential cardiac source of embolism was found in 26/60 case (43%), compared with 14/60 control patients (23%) (p = 0.02; OR = 2.5, 95% CI = 1.2-5.5). Excluding the "still debated," 21/60 case (35%), compared with 8/60 control patients (13%), had a "proven" cardiac source of embolism (p < 0.01; OR = 3.5, 95% CI = 1.4-8.4). Electrocardiogram alone misdiagnosed 72% of the "proven" cardiac sources of embolism, whereas the combination electrocardiogram plus Holter monitoring detected 71%, and electrocardiogram plus echocardiography 62%. Twelve of 21 case patients with at least one proven cardiac source of embolism, were previously unknown. Anticoagulant therapy was required in 32% of case patients and antiarrhythmic therapy in 25% of cases.

CONCLUSIONS

Potential cardiac sources of embolism were more common in patients with segmental, nongangrenous ischemic colitis than in control patients. Therefore, these patients should undergo a routine electrocardiogram, rhythmic Holter monitoring, and transthoracic echocardiography. Anticoagulant therapy should also be considered for this patient population.

Successful local fibrinolytic treatment and balloon angioplasty in superior mesenteric arterial embolism: a case report and literature review

We present the case of a 72-year-old man with atrial fibrillation who developed an embolic occlusion of the superior mesenteric artery. He was successfully treated with local fibrinolysis using streptokinase associated with angioplasty. Such local treatments without the need of surgery are very rarely reported in the literature because of the great difficulty in selecting patients without intestinal necrosis, but represent an important option in the algorithm for the management of acute mesenteric ischemia. The patient was in good condition without recurrent embolism during the six months follow-up.

[Conservative treatment of acute embolisms of the carotid bifurcation]

Embolic events of the carotid bifurcatin are a rare cause of cerebrovascular accidents. We observed two patients who showed a spontaneous recanalisation of an embolic occlusion of the extracranial vessels when treated with conservative procedure using heparin. Both patients had a near complete remission of the symptoms without impairment in their daily activities.