Diagnosis and treatment of paradoxical embolus

Paradoxical Embolism Is an Unusual Etiology of Acute Limb Ischemia in Patients Suffering from COVID-19 Infection

Acute limb ischemia (ALI) is a large contributor to morbidity and mortality annually and can be managed either operatively or medically. ALI is most often caused by arterial embolism or in situ thrombosis and treatment is often dependent upon the severity. Anticoagulation is considered standard of care and first line therapy. However, more severe cases of ALI require surgical intervention.Paradoxical emboli are a rare and potentially under-appreciated cause of ALI. They arise when venous emboli, from a variety of sources, traverse a patent foramen ovale (PFO) to enter the arterial system, compromising blood flow to the affected end organ. In most cases, they can only be proven if the thrombus is identified as it crosses the cardiac defect, at which point it is an indication for surgery requiring PFO closure, management for the ischemia itself, and possible intervention for the embolism.In this report, we identify and discuss management of a series of cases where ALI was precipitated by PFOs that were discovered in the context of a pulmonary emboli that developed into paradoxical emboli. All patients had a confirmed diagnosis of COVID-19 which has been associated with a state of hypercoagulability and subsequent thrombus formation.

Acute ischemia of the upper and lower limbs: Tailoring the treatment to the underlying etiology

Acute limb ischemia (ALI) can be a devastating clinical emergency with potentially limb- or life-threatening consequences. It is defined as a quickly developing or sudden decrease in limb perfusion producing new or worsening symptoms and signs, often threatening limb viability. ALI is commonly related to an acute arterial occlusion. Rarely, extensive venous occlusion can lead to upper and lower extremities ischemia (ie, phlegmasia). The incidence of acute peripheral arterial occlusion causing ALI is approximately 1.5 cases per 10,000 people per year. The clinical presentation depends on the etiology and whether the patient has underlying peripheral artery disease. Except for traumas, the most common etiologies are embolic or thrombotic events. Peripheral embolism, likely related to embolic heart disease, is the most common cause of acute upper extremity ischemia. However, an acute thrombotic event may occur in native arteries, at the site of a pre-existing atherosclerotic plaque, or as a failure of previous vascular interventions. The presence of an aneurysm may predispose to ALI for both embolic and thrombotic mechanisms. Immediate diagnosis, accurate assessment of limb viability, and prompt intervention, when needed, play important roles in salvaging the affected limb and preventing major amputation. Severity of symptoms is usually dependent on the amount of surrounding arterial collateralization, which may often reflect a pre-existing chronic vascular disease. For this reason, early recognition of the underlying etiology is crucial for choice of best management and definitely for treatment success. Any error in the initial evaluation may negatively affect the functional prognosis of the limb and endanger the patient's life. The aim of this article was to discuss diagnosis, etiology, pathophysiology, and treatment of patients with acute ischemia of the upper and lower limbs.

Acute arterial occlusion resulting from paradoxical embolism - case report and literature review

A embolia paradoxal é a transposição de um trombo originário da circulação sistêmica venosa para a arterial através de um defeito cardíaco, mais comumente o forame oval pérvio (FOP). A manifestação mais comum é o acidente cerebrovascular. A oclusão arterial aguda (OAA) é rara, requer alta suspeição diagnóstica e corresponde a menos de 2% de todos casos de embolia arterial. O tromboembolismo pulmonar (TEP) é a causa mais comum de elevação temporária do shunt direita-esquerda em pacientes com FOP e ocorre em pelo menos 60% dos casos de embolia paradoxal. Em 2019, um homem de 27 anos, sem fator para hipercoagulabilidade, deu entrada no Hospital Universitário do ABC, com quadro de OAA grau I Rutherford em membros inferiores secundária a tromboembolismo através de FOP prévio não diagnosticado, associado a trombose venosa profunda de membro inferior direito e TEP bilateral. O manejo incluiu anticoagulação plena e encaminhamento para cirurgia cardíaca.

A Unique Case of Inferior Vena Cava Aneurysm Complicated with Pulmonary Embolism and Cerebral Infarction

Inferior vena cava (IVC) aneurysms rarely occur. They are commonly detected incidentally since they present with mild or no symptoms. This was the first study to report a fatal case of a saccular IVC aneurysm with pulmonary embolism and cerebral infarction. The patient developed cardiac arrest five minutes after arriving at the emergency department, and spontaneous circulation was restored after two minutes of cardiopulmonary resuscitation. Computed tomography scans of the brain, chest, and abdomen–pelvis were obtained. The patient was diagnosed with a saccular aneurysm of the IVC measuring 8 × 11 cm, massive embolism of both pulmonary arteries, and cerebral infarction. An electroencephalogram, taken on the third day of hospitalization, suggested brain death, and the patient died on the eleventh day of hospitalization. This case report highlights that an IVC aneurysm with pulmonary embolism can be associated with paradoxical emboli-induced cerebral infarction, which is fatal.

Characteristics and clinical indicators of concomitant venous thromboembolism in acute limb ischemia

BACKGROUND

Venous thromboembolism (VTE) concomitant to acute limb ischemia (ALI) is rarely reported. The aim of the study was to investigate characteristics and identify clinical indicators of VTE in patients with ALI.

METHODS

Electronic medical record was used to identify patients diagnosed with ALI from January 2013 to June 2019. Eligible patients were categorized as VTE or non-VTE based on the presence or absence of concomitant VTE. Univariate analysis and multivariate analysis for indicators of VTE were performed.

RESULTS

A total of 153 patients with 161 ischemic limbs were enrolled. Venous duplex ultrasound (DUS) for 149 patients (157 ischemic limbs) revealed deep vein thrombosis (DVT) in 38 (24.2%) ischemic limbs of 37 (24.8%) patients. Five femoral DVTs were found intraoperatively. Six patients had pulmonary embolism (PE) and three of them died. In all, 43 (28.1%) ALI patients were diagnosed with VTE. They were treated with trans-arterial catheter-directed thrombolysis (N.=22), embolectomy (N.=9), primary amputation (N.=4) and anticoagulation alone (N.=8). The univariate analysis indicated that symptoms ≥ 2 days [odds ratio (OR): 3.42, 95%CI:1.54-7.62], Rutherford classification IIb-III (OR: 9.17, 95%CI: 2.10-40.12), leg swelling (OR: 4.44, 95%CI: 2.07-9.53), neutrophil ratio ≥0.80 (OR: 3.92, 95%CI: 1.72-8.93) and positive D-dimer (OR: 8.44, 95%CI: 3.65-19.53) were indicators of VTE concomitant to ALI. In the multivariate analysis, leg swelling and positive D-dimer appeared to be independent indicators.

CONCLUSIONS

VTE commonly occurs to ALI. Venous DUS for DVT screening should be considered for ALI patients who present one or more of these indicators.

Paradoxical embolism after surgery for breast cancer: a case report

Background

Paradoxical embolism (PDE) presented with concomitant pulmonary embolism (PE) and renal artery embolism (RAE) which occurred to breast cancer patient after breast-conserving therapy, has never been reported.

Case presentation

A 55-year-old female with breast cancer exhibited unexplained hypoxemia, followed with vomiting, diarrhea, unilateral flank pain and abdominal pain after lumpectomy 12 h. The urgent multi-detector row computed tomography (MDCT) confirmed the diagnosis of PE and RAE. Confusingly, the patient had no history of intracardiac defect, cardiac valvular diseases, atrial fibrillation or other cardiovascular disease and the definite cause was still unclear. However, after 10 days of prompt anticoagulant therapy in ICU, she was discharged in good condition.

Conclusion

Breast cancer patients after surgery suffering from unexplained hypoxemia, abdominal pain, vomiting and diarrhea should be highly suspicious of PE or RAE, even PDE. Any clinical presentation on these postoperative patients should be given much more attention to make accurate diagnosis and appropriate interventions.

Venous thromboembolism prophylaxis using the Caprini score

Venous thromboembolism (VTE) including pulmonary embolism (PE) and deep vein thrombosis (DVT) is one of the leading causes of preventable cardiovascular disease in the United States (US) and is the number one preventable cause of death following a surgical procedure. Post-operative VTE is associated with multiple short and long-term complications. We will focus on reviewing the many faces of VTE in detail as they represent common challenging scenarios in clinical practice.

Avascular Necrosis of Bone following Chemotherapy in Cancer Patients with Coagulopathy: Report of Two Cases

We report 2 cases of patients with solid tumors and coagulopathy who experienced avascular necrosis (AVN) of the bone following chemotherapy. Both cases exhibited nontraumatic bilateral AVN of the femoral heads, and one also showed bilateral AVN of the humeral heads. One case had multiple thromboembolic complications, including pulmonary obstructive syndrome and paraneoplastic pain. The other showed multiple paraneoplastic syndromes, with hypercalcemia and thrombocytosis. Groin pain and claudication of the lower extremities developed and persisted. Both patients eventually received bilateral hip arthroplasty due to AVN of both femoral heads.

Paradoxical embolism: Experiences from a single center

OBJECTIVE

To present our treatment experiences and the follow-up data of patients with paradoxical embolism (PDE).

METHODS

The clinical characteristics, management, and follow-up data of all included patients who were diagnosed with PDE at Fuwai Hospital from January 1994 to October 2015 were recorded.

RESULTS

Twelve patients were included; all had a pulmonary embolism, and 8 had deep venous thrombosis. The artery embolisms involved the cerebral artery (7 patients), renal artery (2 patients), mesentery artery (2 patients), popliteal artery (1 patient), descending aorta thrombus (1 patient), and thrombus-straddled patent foramen ovale (PFO) (1 patient). PFO was found in 3 cases. One patient underwent thrombectomy and PFO closure; Six patients received thrombolysis; and 3 patients were implanted with a vena cava filter. Long-term anticoagulation with warfarin was recommended for each patient. One patient died from ventricular fibrillation despite cardiopulmonary resuscitation. Eleven patients were discharged with improvements. No late mortality occurred in 8 patients with a complete follow-up of 10.6-17.7 years. One had a recurrent deep venous thrombosis. No patient had a recurrent pulmonary or arterial embolism. Two patients changed their treatment from warfarin to aspirin; others remained on warfarin. Only 1 case had an occasional gum bleeding.

CONCLUSIONS

PDE treatment including thrombolysis, anticoagulation, and embolectomy should be individualized. We recommend long-term anticoagulation therapy to prevent the recurrence of PDE, especially to those with an intracardiac communication or persistent risk factors for re-thrombosis.

Rare Forms of Peripheral Arterial Embolism: Review of 11 Cases

The purpose of this study was to present 11 patients operated on owing to rare forms of peripheral arterial embolism at the Institute for Cardiovascular Diseases of the Serbian Clinical Center over a period of 20 years.

Three patients were operated on owing to a foreign body embolism, two owing to a septic embolism, three owing to emboli that originated from malignant tissues, two owing to an embolization from cardiac myxoma, and one owing to an embolism from a myxomatous atrial septal defect. The preoperative evaluation included clinical examination, laboratory findings, and electrocardiography; in the majority of cases, ultrasonography and angiography were performed.

Surgical treatment included foreign body extraction in three cases; thromboembolectomy in seven cases, and artery resection and saphenous graft interposition in one patient with septic embolism. In addition, three cardiosurgical procedures were done: aortic valve replacement in the patient with a septic embolism and tumor excision in patients with atrial myxoma.

In addition to the usual clinical signs of acute limb ischemia, in the rare forms of arterial embolism, the presence of certain uncommon clinical symptoms was also observed. The early results of vascular surgical treatment were very good in all patients. Further follow-up revealed a poor prognosis in patients with malignant arterial embolism.

Unusual Cerebral Emboli

The heart and the carotid arteries are the most common sites of origin of embolic disease to the brain. Clots arising from these locations are the most common types of brain emboli. Less common cerebral emboli include air, fat, calcium, infected vegetations, and tumor cells as well as emboli originating in the venous system. Although infarcts can be the final result of any type of embolism, described herein are the ancillary and sometimes unique imaging features of less common types of cerebral emboli that may allow for a specific diagnosis to be made or at least suspected in many patients.

Right to left shunting through communications between the left superior intercostal vein tributaries and the left atrium: a potential cause of paradoxical embolism

OBJECTIVES

To investigate the role of collateral venous pathways between the left brachiocephalic vein (LBV) and the left atrium through an arcade comprising the left superior intercostal vein (LSICV), left vertical vein (LVV), and pulmonary veins as a potential cause of paradoxical embolism.

METHODS

A retrospective search was performed to find symptomatic patients with negative work up for paradoxical emboli whose chest CT or MR angiography by left arm contrast injection showed a visible right to left shunt through the LSICV/LVV collateral pathway (symptomatic group). We also evaluated the characteristics of this collateral pathway in 150 chest CT angiographies from general referrals (comparison group).

RESULTS

We found 7 symptomatic patients. Initial presentations included neurological symptoms in all patients and episodes of hypoxemia in three patients. Communications between the LBV and left atrium through the LSICV/LVV pathway was seen is all 7 cases and confirmed by transesophageal echocardiography in two. An abnormal LBV was seen in 6 cases (absence in one, stenosis in 5). Moderate superior vena cava stenosis was seen in one and acute right subclavian vein thrombosis in one. Six patients had past history of an upper extremity central line placement. In the comparison group, LSICV was seen in 73 (48%), connecting to the hemiazygos vein in 41, to a LVV in 19 and to the left atrium in 7.

CONCLUSION

LSICV/LVV collaterals are common and can be a potential route for paradoxical emboli especially when stenosis of a draining vein such as LBV exists.

Paradoxical cerebral embolism after total knee arthroplasty

Deep vein thrombosis is a frequent complication following total joint arthroplasty and other major orthopedic procedures. Pulmonary embolism occurs with or without a diagnosis of deep vein thrombosis, although infrequently (1.5%-10%). In patients with congenital cardiac defects, such as a patent foramen ovale, paradoxical cerebral embolism may also occur. This article describes a case of a 52-year-old woman who sustained a paradoxical cerebral embolism following total knee arthroplasty. In the workup of a patient with a known murmur and stroke symptoms, paradoxical cerebral embolism should be included in the differential. The initial evaluation should incorporate transesophageal echocardiography because of its accuracy in the demonstration of the cardiac physiology. An abnormal intracardiac or intrapulmonary shunt is essential for paradoxical cerebral embolism, allowing the entrance of the thrombus into cerebral circulation from the venous system. No clear consensus has been reached on the management of patients at risk for paradoxical cerebral embolism prior to orthopedic procedures. However, when an embolic stroke is diagnosed acutely, ideal management includes thrombolytic therapy, but further research is needed to confirm that this is the correct management. Due to the risk of recurrence, postoperative thromboprophylaxis is recommended with or without closure of the foramen ovale. Most importantly, and as demonstrated by the current patient, who partially recovered but did not require walking assistance after 2-year follow-up, treating physicians should be prepared to counsel patients through a lengthened physical rehabilitative process.

[Acute massive pulmonary embolism with thrombus entrapped in patent foramen ovale]

Thromboembolic disease is a potentially severe pathology, which can represent a life threat if it is not diagnosed early, especially when the cardiopulmonary backup is limited. When its clinical feature implies a massive occlusion of the arterial pulmonary tree and a cardiac failure is ensued, it can be seriously life threatening, even for young patients. Less frequent features as right or left atrium thrombosis could increase de morbidity and mortality of this disease. We present the case of a young woman with severe respiratory insufficiency. The CT pulmonary angiography revealed an acute massive pulmonary embolism, with a right atrium thrombus extending towards the left atrium, through a patent foramen ovale. We discuss the imaging characteristics and the importance of the precise information obtained with the CT pulmonary angiography, essential in the rapid establishment of a given treatment protocol and an outcome prognosis for the patient.

Multiorgan paradoxical embolism consequent to acute pulmonary thromboembolism with patent foramen ovale: a case report

Paradoxical embolism is defined as a systemic arterial embolism requiring the passage of a venous thrombus into the arterial circulatory system through a right-to-left shunt. It is a relatively rare phenomenon, representing about 2% of all cases of arterial embolism. We report a case of a 79-years-old woman admitted to hospital because of dyspnea and lower left limb pain. CT scan revealed multiple thrombi to kidney, lower limb and superior mesenteric artery during acute pulmonary embolism. Echocardiogram documented a patent foramen ovale with a right-to-left shunt. The patient was treated with thrombolytic therapy and heparin with progressive improvement of symptoms and resolution of pulmonary embolism and peripheral thrombosis. Patent foramen ovale closure was not performed because a life-long anticoagulation therapy was necessary, a tunnel-type patent foramen ovale may increases difficulty in realizing device implantation and there are no clear evidence-based guidelines to date addressing treatment in presence of a patent foramen ovale.

Paradoxical embolism secondary to ovarian carcinoma resulting in stroke

A middle aged woman presented with a posterior fossa stroke after an elective ear nose and throat procedure. The occurrence of a paradoxical embolism was suspected. The evidence for this and a discussion about this condition are presented.

"Lots of clots": multiple thromboemboli including a huge paradoxical embolus in a 29-year old man

Paradoxical embolism occurs when a venous thrombus passes into the arterial circulation, most commonly through an intracardiac shunt. This phenomenon has been associated with catastrophic outcomes such as stroke and ischemic limb. We report the case of a 29-year old man with multiple thromboemboli including a deep venous thrombus, bilateral pulmonary emboli, and a paradoxical embolus into his left subclavian artery. We postulate the underlying predisposition and sequence of events that may have resulted in these multiple blood clots and report on his successful surgical outcome.

Paradoxical embolism: a rare life- and limb-threatening emergency

This article presents a case of a 43-year-old man with paradoxical embolism. The patient had simultaneous deep venous thrombosis, pulmonary embolism and bilateral limb-threatening arterial occlusions. The unifying diagnosis was paradoxical embolism through a previously undetected atrial septal defect. Suggestions for the evaluation and emergency management of paradoxical embolism are outlined, and the literature is briefly reviewed.

Acute leriche syndrome due to paradoxical embolism

Paradoxical embolism, describing the passage of venous or right-sided cardiac thrombus into the arterial or systemic circulation through patent foramen ovale, is an uncommon cause of acute arterial occlusion. Here, we report acute Leriche syndrome in a young woman attributable to paradoxical embolism. Ischaemia, patent foramen ovale, and venous thrombosis were the triad of evidence for paradoxical embolism.

Paradoxical embolization via a patent foramen ovale following acute pulmonary embolism

The foramen ovale is usually obliterated following establishment of the adult circulation but remains patent in 25% of individuals. This potential communication between the venous and arterial circulations can allow thromboembolic material to bypass the lungs and enter the systemic circulation. We report two cases of paradoxical embolization through a patent foramen ovale following acute large pulmonary embolism (PE) and discuss the factors that predispose to paradoxical embolization following PE.