Successful surgical treatment of impending paradoxical embolism with pulmonary embolism and myocardial infarction.

BACKGROUND: Paradoxical embolism is a rare cause of acute arterial occlusion. This phenomenon arises when embolic material travels from the venous system crosses an abnormal shunt such as patent foramen ovale, atrial septal defects, ventricular septal defects, or pulmonary arteriovenous malformations, into the arterial system. Impending paradoxical embolism refers to the presence of an entrapped thrombus in the patent foramen ovale. CASE PRESENTATION: We report a case of a 68-year-old female patient who presented with an impending paradoxical embolism, alongside both concomitant pulmonary embolism and myocardial infarction with ST-segment elevation. Swiftly addressed through emergency cardiac surgery and systemic anticoagulation, the patient's condition was effectively treated. CONCLUSIONS: While the ideal treatment strategy for impending paradoxical embolism remains a topic of debate due to limited and inconclusive evidence, emergent open surgery should be contemplated in patients as it signifies a critical clinical emergency.

[Thromboembolic diseases from a cardiological point of view]. / Thromboembolische Erkrankungen aus kardiologischer Sicht.

Thromboembolic disease is associated with a high mortality. It can be divided into two groups: embolism from a venous and embolism from an arterial side. This article gives an overview on thromboembolic disease (with a focus on pulmonary embolism and ischemic stroke) from a cardiologist's perspective.The therapeutic options for acute pulmonary embolism range from anticoagulation to fibrinolysis to interventional recanalization and surgery. The deciding factor for choice of therapy is the risk of early death. Besides clinical parameters, laboratory markers like cardiac troponin and right ventricular function on echocardiography or CTPA (computed tomography pulmonary angiography) are used to determine the early mortality risk. In hemodynamically instable patients, immediate thrombolysis is required, whereas patients with intermediate and low risk can be treated with anticoagulation. Interventional recanalization is currently being studied in patients at risk for development of CTEPH (chronic thromboembolic pulmonary hypertension) or an intermediate risk of early mortality.In ischemic stroke, early interdisciplinary workup involving a cardiologist is paramount. Post stroke screening should include monitoring for arrythmias (especially atrial fibrillation) and transthoracic echocardiography as well as sonography of extra- and intracranial arteries. If no embolic source can be detected (embolic stroke of undetermined source), transesophageal echo can be helpful to detect intracardiac shunts like patent foramen ovale (PFO) or intracardiac tumors. Post stroke care includes secondary prevention measures like risk factor modification and lipid lowering therapy as well as anticoagulation. In high risk for paradoxical embolization, interventional PFO closure can be performed. Interventional closure of the left atrial appendage (LAA) can be discussed in patients with both high thromboembolic and bleeding risk.

Saddle Pulmonary Embolus and Simultaneous Common Carotid and Subclavian Artery Emboli.

A patent foramen ovale (PFO) is present in 27-35% of the population. Right to left cardiac shunts predispose patients to arterial emboli in the presence of venous thromboembolisms. Paradoxical embolus should be suspected in patients with deep venous thrombosis (DVT) and arterial emboli. A 45-year-old man with hypercoagulability and history of DVT presented with a week-long history of chest pain, shortness of breath, and left arm numbness. Imaging showed a saddle pulmonary embolus (PE) and emboli involving the aortic arch, left common carotid, and left subclavian artery. The patient proceeded with an endovascular thrombectomy of the pulmonary artery, followed by open thrombectomy. Echocardiogram confirmed a right to left intra-cardiac shunt consistent with a PFO. Paradoxical emboli are rare manifestations of venous thromboemboli in patients with right to left intra-cardiac shunts. Patients should be evaluated for these to help prevent further manifestations.

Venous thromboembolism with renal infarct due to paradoxical embolism.

Paradoxical thromboembolism has variable presentation depending on site of embolisation. An African-American man in his 40s presented with severe abdominal pain, watery stools and exertional dyspnoea. At presentation, he was tachycardic and hypertensive. Labwork showed elevated creatinine with unknown baseline. Urinalysis showed pyuria. A CT scan was unremarkable. He was admitted with working diagnosis of acute viral gastroenteritis and prerenal acute kidney injury and supportive care was instituted. On day 2, the pain migrated to left flank. Renal artery duplex ruled out renovascular hypertension but showed a lack of distal renal perfusion. MRI confirmed a renal infarct with renal artery thrombosis. Transoesophageal echocardiogram confirmed a patent foramen ovale. Simultaneous arterial and venous thrombosis require hypercoagulable workup, including investigation for malignancy, infection or thrombophilia. Rarely, venous thromboembolism can directly cause arterial thrombosis by 'paradoxical thromboembolism'. Given the rarity of renal infarct, high index of clinical suspicion is necessary.

Simultaneously Occurring Ischemic Stroke, Leg Artery Occlusion, and Pulmonary Embolism Induced by a Uterine Myoma.

OBJECTIVES: Paradoxical embolism from venous thrombosis through the patent foramen ovale is a rare but well-known cause of stroke in young adults. Here, we report a case of simultaneous middle cerebral artery infarction, multiple occlusions of the leg arteries, and pulmonary thromboembolism from the venous thrombus, all due to compression of the external iliac vein by a uterine leiomyoma. MATERIALS AND METHODS (CASE PRESENTATION): A 44-year-old woman presented with left hemiparesis and central-type left facial palsy. She denied a history of hypertension, diabetes mellitus, previous cerebral infarction, myocardial infarction, smoking, or oral contraceptive use. The patient recovered completely after injection of tissue plasminogen activator. Brain diffusion-weighted imaging showed an acute right middle cerebral artery infarction. Transcranial Doppler with saline agitation test revealed a right-to-left shunt, suggesting a patent foramen ovale. Chest computed tomography revealed multiple pulmonary thromboembolisms. Lower extremity sonography and lower extremity computed tomography revealed a multifocal thrombus in the major veins and arteries of the left leg. Moreover, a large uterine myoma compressing the left external iliac vein was noted on lower extremity computed tomography. RESULTS: After the treatment of pulmonary thromboembolism and venous thrombosis with rivaroxaban, surgical thrombectomy of the left popliteal artery, patent foramen ovale closure, and total hysterectomy were performed. Subsequently, she had no recurrent paradoxical embolism or pulmonary thromboembolism. CONCLUSION: Structural abnormalities in the pelvic cavity are not commonly suspected as stroke etiology. However, examination of the pelvic cavity is advisable in young female stroke patients with pulmonary thromboembolism or other paradoxical embolisms.

Carbon dioxide: the cause of devastating stroke without hemodynamic compromise during laparoscopic nephrectomy with injury of the inferior vena cava: A case report.

RATIONALE: Carbon dioxide pneumoperitoneum in laparoscopic surgery can bring about occult perioperative cerebral infarction, advancing our understanding of the causes of severe postoperative delayed recovery. PATIENT CONCERNS: Here, we report the case of a 35-year-old woman who underwent a right renal tumor resection in our institution, during which a raised pneumoperitoneum pressure (from 15 to 20 mm Hg) was adopted by the surgeon to prevent errhysis and to help stop the bleeding. Despite an accidental minor tearing of the inferior vena cava, vital signs remained stable throughout the procedure, and no obvious abnormality was observed in either end tidal carbon dioxide values or blood gas analysis. However, the patient unexpectedly suffered delayed recovery after the operation, presenting incomplete left hemiplegia and a positive Babinski sign. DIAGNOSES: Perioperative stroke was diagnosed by anesthesiologists, after excluding the effects of anesthesia. Cerebral hemorrhage was excluded, as no obvious abnormality was found in the density of brain parenchyma in the emergency computed tomography examination, and a digital subtraction angiography showed no abnormal thrombosis. Further magnetic resonance diagnosis led us to consider diffuse gas embolisms to be the cause of this acute stroke; a right echocardiography revealed that a patent foramen ovale (PFO) may account for the global cerebral gas embolisms. INTERVENTIONS: The patient received neuroprotective drugs (Vinpocetine, Edaravone, and Xingnaojing, which are commonly used as a standard of care in China), antiplatelets and other symptomatic treatments, plus dexamethasone to relieve edema. A contrast-enhanced echocardiography of the right heart was performed, the results of which were consistent with the sonography of a PFO. OUTCOMES: The patient was hospitalized for 14 days and eventually discharged after recovery. At the latest follow-up in August 2019, the patient recovered without residual neurological sequelae. LESSONS: Our results emphasize the need for vigilance regarding adverse cardiovascular and neurological events caused by carbon dioxide gas embolisms when encountering the inadvertent situation of vessels rupturing. Timely monitoring of paradoxical gas embolism by transoesophageal echocardiography is necessary and can avert the risk of severe complications. Urgent consideration should be given to stopping pneumoperitoneum and switching to laparotomy for hemostasis so that the patient can obtain the best benefit-risk ratio.

Avaliação Ecocardiográfica de Pacientes com Forame Oval Patente e Acidente Vascular Cerebral Criptogênico / Echocardiographic Evaluation of Patients with Patent Foramen Ovale and Cryptogenic Stroke

Recentes estudos indicaram que o forame oval patente (FOP) pode ser responsável pelo acidente vascular cerebral criptogênico (AVC) em pacientes jovens que apresentam condições anatômicas favoráveis a essa anomalia e que a oclusão transcateter reduz a incidência do acidente vascular cerebral quando comparada ao tratamento clínico. A injeção de soro agitado durante o estudo ecocardiográfico, associada à manobra de Valsalva, pode evidenciar shunt direita-esquerda com alta sensibilidade (89%) e especificidade (92%) quando se utiliza o ecocardiograma transesofágico. Avaliando as características clínicas de pacientes com acidente vascular cerebral e forame oval patente, o trial Risk of Paradoxical Embolism, conhecido pela sigla RoPE, (Risk of Paradoxical Embolism) estabeleceu um escore de risco para acidente vascular cerebral criptogênico e, por meio de um modelo de regressão multivariada, identificou seis variáveis: idade, presença de isquemia cortical, diabetes, hipertensão, AVC e acidente isquêmico transitório prévio. Os escores mais elevados foram observados em jovens com AVC e sem fatores de risco vascular e os escores mais baixos em idosos com fatores de risco vascular, de modo que o forame oval patente sugere ser acidental. Condições anatômicas do FOP predispõem à embolia sistêmica (separação do FOP > 2 mm; túnel do FOP > 10 mm; ângulo entre a veia cava inferior e o flap do FOP <10°; intensidade do shunt com manobra de Valsalva; presença de aneurisma do septo interatrial e rede de Chiari ou válvula de Eustáquio proeminente). O fechamento do FOP pode prevenir a embolia paradoxal, reduzindo a incidência de acidente vascular cerebral em pacientes considerados com de risco elevado. A relação entre Acidente Vascular Cerebral (AVC) criptogênico e a presença de Forame Oval Patente (FOP) tem despertado particular interesse, baseada em estudos recentes que demonstraram que a oclusão transcateter do FOP reduziu a incidência de AVC criptogênico, quando comparado ao tratamento medicamentoso.1 Trombos atravessando o forame oval podem ser observados em exames ecocardiográficos e em autópsias, confirmando esse mecanismo como responsável pela embolia paradoxal, ou seja, um trombo venoso passando para a circulação arterial por um shunt direita-esquerda. Entretanto, essa visualização ecocardiográfica é rara e existem poucos estudos publicados2,3 (Figura 1). Alguns estudos clínicos demonstram a propensão do FOP ser o responsável pela embolia paradoxal. Pacientes portadores de diabetes, hipertensão arterial sistêmica e doença arterial coronária têm baixa prevalência para o FOP ser o responsável pela embolia paradoxal. Por outro lado, história de trombose venosa profunda, embolia pulmonar, hipertensão pulmonar, viagens prolongadas, manobra de Valsalva precedendo o início de sintomas de AVC, enxaqueca e apneia do sono tem sido descrita como fatores de risco independentes para a associação entre FOP e eventos cerebrovasculares.4 Mesmo sendo pouco frequente a visualização de trombos em forame oval, a observação epidemiológica nos leva a acreditar que o FOP é o responsável por um número considerável de acidentes vasculares cerebrais.5 A prevalência de FOP em um estudo com autópsia em 965 corações normais é de 27%, com similar distribuição entre homens e mulheres. Essa prevalência declina com a idade, sendo de 34% em menores de 30 anos, 25% entre 30 e 80 anos e 20% em maiores de 80 anos.6 Em pacientes com AVC criptogênico, entretanto, a prevalência é particularmente elevada, chegando a 40% em pacientes com idade inferior a 55 anos.7 É importante ressaltar que a presença de FOP em pacientes com AVC criptogênico não é a única etiologia para o embolismo paradoxal. Outros mecanismos podem ser responsáveis, como fibrilação atrial não detectada, tumores cardíacos (mixoma e fibroeslastomas), presença de contraste ecocardiográfico espontâneo em átrio esquerdo, valvopatia mitral reumática, calcificação do anel valvar mitral, próteses cardíacas biológicas e mecânicas, estados de hipercoagulabilidade e ateroma de aorta ascendente.8 O estudo ecocardiográfico é parte da rotina na avaliação do FOP, principalmente o Ecocardiograma Transesofágico (ETE) com utilização de solução salina agitada (macrobolhas). Considera-se um shunt pequeno quando passam de três a dez bolhas, médio de dez a 30 bolhas e grande se mais de 30 bolhas contadas nos primeiros batimentos após a injeção.9 Além da detecção do shunt, o ETE avalia as características anatômicas do FOP, assim como o diagnóstico diferencial com a comunicação interatrial e com o shunt pulmonar.10,11 Trabalhos comparando o ETE utilizando macrobolhas com os achados de autópsia mostram sensibilidade de 89% e especificidade de 92%, sendo que a autópsia é considerada padrão-ouro.12(AU)

Oclusão arterial aguda consequente a embolia paradoxal - relato de caso e revisão de literatura / Acute arterial occlusion resulting from paradoxical embolism - case report and literature review

Resumo 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.

Resumo 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.

Acute Ischemic Stroke as a Result of Paradoxical Embolus in a Patient with Renal Cell Carcinoma, Intravenous Tumor Thrombus Extension, and Patent Foramen Ovale.

INTRODUCTION: Patent foramen ovale is a common congenital cardiac abnormality. An association with acute ischemic stroke is well described. Extension of renal cell carcinoma (RCC) into the adjacent veins is common. Surgical resection is felt to be an effective approach to treatment, even in the setting of extensive venous involvement. CASE REPORT: A 55-year-old woman with recently diagnosed right renal mass and cavoatrial tumor thrombus was transferred to our facility for surgical resection. She subsequently underwent open radical right nephrectomy, regional lymph node dissection, inferior vena cava and right atrial tumor thrombectomy, and resection of the infrahepatic vena cava. An intraoperative transesophageal echocardiogram confirmed the absence of tumor thrombus from the inferior vena cava and right atrium and also identified a patent foramen ovale (PFO). Upon weaning sedation, she was noted to be agitated and have left hemiplegia. Her National Institutes of Health Stroke Scale (NIHSS) was 30 and Glasgow Coma Scale (GCS) 6. The computerized tomography scan of head revealed extensive hypoattenuation right in the middle and left posterior cerebral artery territories. There was associated cerebral edema and 5-mm midline shift. In the setting of devastating neurological injury, her family elected to transition to comfort care and the patient died on the postoperative day 7. CONCLUSIONS: This is the first reported case of intraoperative paradoxical embolism in the setting of RCC with cavoatrial extension and PFO. The presence of PFO may be a risk factor for severe cerebrovascular complications in the surgical management of RCC with venous involvement.

Cardiac arrest in a healthy child due to paradoxical embolus across a previously unrecognised sinus venosus defect.

A previously healthy, preadolescent female suffered an unwitnessed cardiac arrest with prompt return of circulation following bystander initiated resuscitation. Workup demonstrated the cause of her cardiac arrest to be distal left anterior descending coronary artery occlusion with small apical left ventricular transmural myocardial infarction, from a paradoxical embolus traversing a previously undiagnosed large sinus venous defect. This case demonstrates the value of cardiac magnetic resonance imaging may bring to the diagnosis of the pathophysiology leading to cardiac arrest.

Management and clinical outcome of concomitant pulmonary embolism and paradoxical saddle aortic arch embolism.

A 65-year-old man presented in a peri-arrest situation after collapse, he was found hypoxic with ischaemic arms. CT imaging showed massive bilateral pulmonary embolisms (PEs) and an aortic arch embolus extending from brachiocephalic trunk to left subclavian artery. Following intravenous thrombolysis, repeat imaging revealed that the aortic embolus had migrated distally into both axillary arteries and had occluded the right carotid from origin to skull base. Bilateral upper limb embolectomies were carried out from the brachial arteries together with forearm fasciotomies. Left hemianopia related to a right middle cerebral artery territory infarct was managed conservatively; forearm fasciotomy wounds were primarily closed and the patient was discharged on lifelong anticoagulation. A transoesophageal echocardiogram revealed a patent foramen ovale. This case demonstrates a very unusual presentation of concomitant PE and paradoxical saddle aortic arch embolism. A multidisciplinary approach has resulted in an excellent clinical outcome for this complex patient.

Multiple Cerebral Infarctions Due to Patent Foramen Ovale in a Patient with Eosinophilic Granulomatosis with Polyangiitis.

A 51-year-old man was diagnosed with eosinophilic granulomatosis with polyangiitis 6 years ago due to asthma, sinusitis, hypereosinophilia, and peripheral neuropathy based on the diagnostic criteria of American College of Rheumatology, and corticosteroid therapy achieved a remission. One year ago, he was hospitalized due to deep venous thrombosis (DVT) and pulmonary embolism, and rivaroxaban was administrated. He was admitted to our hospital for acute onset of diplopia and right hemiparesis. Peripheral blood examinations disclosed leukocytosis with hypereosinophilia. Perinuclear anti-neutrophil cytoplasmic antibodies were positive. Diffusion-weighted imaging showed multiple fresh ischemic lesions. Chronic ischemic lesions were seen in subcortical cerebral region. No stenosis or occlusion was shown in extracranial and intracranial arteries on magnetic resonance angiography. Ultrasonography of leg vein showed DVT. Right-to-left shunt through patent foramen ovale after Valsalva maneuver was seen on transesophageal echocardiography. Treatment with corticosteroid and cyclophosphamide alleviated clinical deterioration. Rivaroxaban was changed to warfarin. Diplopia and muscle strength of right limbs were improved. This is a first case of multiple cerebral infarction caused by paradoxical embolism due to patent foramen ovale with DVT based on hypercoagulable state of hypereosinophilia. Overall this case illustrates that eosinophilic granulomatosis with polyangiitis can be a risk factor for multiple cerebral infarction in the systemic phase and that transesophageal echocardiography and ultrasonography of leg vein should be conducted in stroke patient with eosinophilic granulomatosis with polyangiitis.

Acute arterial embolism of left lower extremity caused by paradoxical embolism in Ebstein's anomaly: A case report.

INTRODUCTION: Ebstein's anomaly is a benign and stable congenital heart disease for asymptomatic patients. Despite a low incidence of Ebstein's anomaly (EA), patients' quality of life can be badly affected by EA without positive surgical intervention. Especially EA is associated with other congenital heart disease, such as the atrial septal defect, patent foramen ovale, and arterial embolism exclude other reasons, it is often considered to be the consequence of paradoxical embolism, and surgical intervention must be conducted. CASE REPORT: An 11-year-old girl falling off the bed suffered pain from left lower extremity. Echocardiographic evaluation revealed an EA, severe tricuspid regurgitation, and secundum atrial septal defect. Both left leg amputation and cardiac surgery were conducted after recovery. Under the condition of anesthesia cardiopulmonary bypass extracorporeal circulation, atrial septal defect repair and Cone reconstruction of the tricuspid valve were performed. Patient recovered well and left hospital smoothly. DISCUSSION: EA is a rare and complex congenital cardiac malformation. There are about 80% to 90% of EA patients with combined atrial septal defect and patent foramen ovale. Sudden arterial occlusion is very rare especially in childhood. When thoracic roentgenoscopy, arterial blood gas analysis, coagulation test, and echocardiographic of lower extremity deep venous system are all normal, one should consider the possibility of a paradoxical embolism. If patients have the paradoxical embolism or worsening tricuspid regurgitation, the most suitable therapeutic regimen should be chosen according to patients' condition. With surgical techniques and methods renewed continuously, cone reconstruction of the tricuspid valve has been confirmed in clinical trials, which can use its own tissues to form not only central bloodstream, but also the coaption between leaflet and leaflet.

Concomitant coronary and pulmonary embolism associated with patent foramen ovale: A case report.

RATIONALE: The differential diagnosis of acute chest pain is very important, and can sometimes be challenging. Related diseases share a number of risk factors, and occasionally, 1 condition causes another disease to develop. PATIENT CONCERNS: We described a 59-year-old man who presented to emergency department complaining of chest pain. DIAGNOSES: He was suffered acute myocardial infarction (MI) and pulmonary embolism (PE) simultaneously. INTERVENTIONS: Dual antiplatelet therapy, statin, and low molecular weight heparin were administrated during his stay. The searches for cancers, autoimmune diseases, and hematologic diseases were unremarkable, ruling out a hypercoagulable state. Subsequent ultrasound scan revealed a thrombus in a vein of the lower left extremity. Thus, paradoxical embolism was highly suspected. OUTCOMES: Paradoxical embolism is a rare cause of acute MI, which may have occurred in our patient. This was evidenced by a previously unrecognized patent foramen ovale (PFO) with a right-to-left atrial shunt detected using contrast transesophageal echocardiography. LESSONS: Acute MI complicated with PE is not common in the clinical setting. The fatal condition is difficult to diagnose because of the similar symptoms and confusing causes. Paradoxical embolism can cause this phenomenon, and physicians should be highly vigilant in the search for a PFO in cases of paradoxical embolism.

Cryptogenic Stroke with a Patent Foramen Ovale: Medical Therapy, Percutaneous Intervention, or Surgery.

More than one third of ischemic strokes have an unidentifiable cause. Patent foramen ovale (PFO) plays a controversial role in this subset of patients. The evidence for and against the hypothesis of paradoxical embolism is reviewed and we discuss the optimal management of a PFO under different circumstances.

Embolus entrapped in patent foramen ovale: impending paradoxical embolism.

An impending paradoxical embolism is a rare finding, with fewer than 200 cases being documented so far. A 68-year-old woman, who presented with 3 weeks of increasing exertional dyspnea and exercise intolerance, underwent transesophageal echocardiography with a finding of an embolus in both right and left atria. At an emergent cardiac surgery, a worm-shaped, 5-cm-long thrombus was found in the right atrium, it was protruding to left atrium through the foramen ovale. The thrombus was removed intact, and the foramen ovale was closed. By our experience, an emergent cardiac surgery should always be considered as a treatment option for impending paradoxical embolism.

Paradoxical embolus in transit.

Thrombus straddling a patent foramen ovale, namely, a paradoxical embolus in transit, is a rarely identified entity signifying impending arterial embolism. We report a series of 3 patients with preoperatively or intraoperatively identified paradoxical embolus in transit. All patients underwent surgical evacuation and had unremarkable postoperative courses with no episodes of arterial embolization. Surgical embolectomy should be considered early in the treatment of paradoxical embolus in transit.

Ischaemic stroke secondary to paradoxical emboli through an arteriovenous malformation of the lung in a patient with known breast cancer.

We presented an unusual case of a young woman who suffered an ischaemic stroke while receiving chemotherapy postsurgery for breast cancer. No cause was identified at that time and a year later an incidental pulmonary arteriovenous malformation (PAVM) was diagnosed during an MR review of her breasts. This was confirmed on the CT and she subsequently underwent successful endovascular embolisation. Ischaemic stroke as a presenting symptom of an undiagnosed PAVM or hereditary haemorrhagic telangiectasia is rare. PAVM is a clinically important and treatable cause of ischaemic stroke and should therefore be considered in young patients with ischaemic stroke, with or without concurrent venous thrombotic risk factors. As far as we are aware, this is the first reported incidental finding of PAVM on MR of the breast.