Recurrent transient ischemic attacks in a patient with intrapulmonary arteriovenous shunting detected after closure of a patent foramen ovale.

Paradoxical embolism through right-to-left shunts is widely accepted as a potential cause of cerebral ischemia. Contrast echocardiography is an excellent tool for detection of these shunts. The timing of the appearance of bubbles in the left atrium (ie, early vs late) allows differentiation of foramen ovale patency from intrapulmonary shunting as a result of arteriovenous malformations. We report a patient with recurrent neurologic deficit after surgical closure of a patent foramen ovale. Transesophageal echocardiography demonstrated residual right-to-left shunting from previously unrecognized pulmonary arteriovenous malformations associated with hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu). This case illustrates the fact that contrast echocardiography may fail to identify intrapulmonary shunts when a resting patent foramen ovale coexists.     

Cerebral infarction following thrombolysis for massive pulmonary embolism

A 29-year-old male developed a fatal stroke 6 h after successful thrombolysis for massive pulmonary embolism. Autopsy showed thrombus protruding through a patent foramen ovale (PFO). A strand of thrombus extended from the aortic arch into the left common carotid artery. The brain showed extensive infarction of the left fronto-parietal area. Thrombolysis caused initial disintegration of the embolism. It is likely that thrombolysis caused fragments of clot to later break lose and embolise into the cerebral circulation. We discuss the need for risk stratification in patients who present with massive pulmonary embolism and PFO.     

Crossing atrial thrombus in a patient with recurrent pulmonary embolism

OBJECTIVES: To report the detection of a thrombus entrapped in a patent foramen ovale by echocardiography in a patient with recurrent pulmonary embolism. DESIGN: Case report. SETTING: Intensive care unit of a university hospital. PATIENT: A 62-yr-old man with initial deep venous thrombosis and recurrent minor pulmonary embolism followed by a severe embolic event with transitory hemiparesis 10 days after prostatectomy. INTERVENTION: Systemic anticoagulation, surgical removal of a crossing atrial thrombus, closure of a patent foramen ovale, and venous thrombectomy. MEASUREMENTS AND MAIN RESULTS: Transesophageal echocardiography revealed a large thrombus entrapped in a patent foramen ovale with portions in all four heart chambers. Intraoperatively, a 19-cm-long thrombus, shaped like the pelvic veins, was found. The patient was successfully weaned from cardiopulmonary bypass, requiring temporary positive inotropic support because of right ventricular dysfunction. Within 24 hrs of the operation, the patient was discharged to the intermediate care unit. CONCLUSIONS: Recurrent pulmonary embolism can potentially result in paradoxic embolism in patients with a patent foramen ovale. In such patients, it may be crucial to monitor right ventricular function and exclude right-to-left shunts by transesophageal echocardiography, regardless of clinical symptoms. The patent foramen ovale should be closed. This case emphasizes an important indication for transesophageal echocardiography in critically ill patients.     

Major pulmonary embolism and hemodynamic stability from shunting through a patent foramen ovale

While the combination of a patent foramen ovale (PFO) and thromboembolic disease is thought to portend increased morbidity and mortality, PFO presence in the setting of major pulmonary embolism (PE) may serve as a means to rescue patients from immediate hemodynamic collapse and death. We present two patients with major pulmonary embolism and right-to-left shunting consistent with PFO as seen on transthoracic echocardiography. In the setting of major PE, PFO may prevent acute right ventricular failure by acting as a 'pop-off' valve, alleviating increased ventricular pressures; but concomitantly portend deleterious effects in the form of paradoxical embolism and intractable hypoxemia.     

Paradoxical Embolism Due to Open Foramen Ovale with Atrial Septal Aneurysm as a Cause of Myocardial Infarction in a Young Male

Paradoxical embolism is a rare cause of myocardial infarction. We present a case of a young man who was admitted to our hospital with an inferior myocardial infarction. Coronary arteriography showed a total distal occlusion of a posterolateral branch of the circumflex artery. Contrast-enhanced echocardiography showed a large atrial septal aneurysm with a patent foramen ovale and massive right-to-left shunting. No other sources of cardiac embolism could be identified. In this case, paradoxical embolism probably has resulted in myocardial infarction.     

Patent foramen ovale as lifesaving purging valve.

Patent foramen ovale is considered as a potential risk factor for stroke owing to paradoxic embolism, leading to the question "to close or not to close the patent foramen ovale". We report a 26-year-old woman with chest pain, dyspnoea, sudden severe pain in both legs and paraplegia. Thoracic and abdominal computed tomography revealed massive pulmonary embolism and complete obstruction of the abdominal aorta. Interventional removal of the aortic thrombus was undertaken using the Fogarty catheter technique via the femoral arterial approach. As a result of worsening of cardiopulmonary function during the procedure, additional local thrombolysis, with a total of 50 mg recombinant tissue plasminogen activator, and fragmentation of the thrombus in the right pulmonary artery were performed via a femoral vein approach. Ultrasound studies revealed a patent foramen ovale of about 12 mm diameter with a significant right to left shunt. Under favourable conditions, a patent foramen ovale may allow the escape of a thrombus, sufficient to cause a potentially fatal pulmonary embolism, into the arterial system, where it can be removed by interventional manoeuvres.     

Two cases of complications of the thrombolysis of right heart free-floating thrombi with pulmonary embolism: important role of echocardiographically based management

We present two cases where successful thrombolysis of right heart thrombi and pulmonary embolism was accompanied by serious adverse events. In patient 1 with massive pulmonary thromboembolism, transesophageal ultrasound revealed large right atrial thrombus entrapped in a patent foramen ovale. Initial treatment with heparin was substituted with thrombolysis, which resulted in clinical improvement and dissolution of right heart thrombus but was followed by fatal intracerebral haemorrhage. In patient 2, thrombolysis caused mobilisation of thrombotic mass as evidenced by disappearance of thrombus on ultrasound. Massive pulmonary thromboembolism resulted in circulatory collapse. Short cardiopulmonary resuscitation restored spontaneous circulation and the patient recovered completely.     

Persistent hypoxemia occurring as a complication of tricuspid valve endocarditis.

A 33-year-old woman had intravenous drug-associated tricuspid valve infective endocarditis. Despite resolution of septic pulmonary emboli, hypoxemia persisted. We report a case of right-to-left shunting across a previously insignificant patent foramen ovale documented by contrast transesophageal echocardiography. Although a rare complication of tricuspid endocarditis, clinicians should be aware of this potential correctable complication.     

Patent foramen ovale: a nonfunctional embryological remnant or a potential cause of significant pathology?

A patent foramen ovale (PFO) is an embryological remnant found in 27% of adults. It is a potential right-to-left intracardiac shunt. Shunting may be the result of reversal in the interatrial pressure gradient or abnormal streaming of blood in the right atrium. The pathologic consequences of right-to-left shunting include hypoxemia and paradoxical embolism. PFO may exacerbate preexisting hypoxemia or be its primary cause. Paradoxical embolism through a PFO is well documented. Its role in cryptogenic stroke remains controversial. A PFO may be detected by both invasive and noninvasive techniques. Contrast transesophageal echocardiography with provocative maneuvers is the diagnostic method of choice allowing visualization of the shunt. Patients with cryptogenic stroke should be screened for a PFO. If detected, noninvasive studies for deep vein thrombosis are recommended. Treatment must be tailored to the presentation. Surgical or transcatheter closure is recommended for hypoxemia. Prevention of venous embolism (air or thrombus) with or without closure of the PFO is recommended for paradoxical embolism.     

Paradoxical embolism-report of a case involving four organ systems

Paradoxical embolism through a patent foramen ovale (PFO) can involve multiple organs simultaneously. The most commonly involved sites are the cerebrum and the extremities. Paradoxical embolism to coronary arteries or upper extremities is relatively uncommon. We report a case of acute pulmonary embolism and paradoxical embolism through a patent foramen ovale involving the left upper extremity, brain, and coronary artery. Early diagnosis in the emergency department was made by a trans-esophageal echocardiogram, and the patient was successfully treated with intravenous t-PA and heparin. Patients with acute pulmonary embolism or deep venous thrombosis who also develop signs of systemic embolism should be evaluated for a patent foramen ovale.     

Paradoxical embolus illustrating speed of action of recombinant tissue plasminogen activator in massive pulmonary embolism

A case of a patient who presented with massive pulmonary embolism (PE) requiring thrombolysis with alteplase is reported. The subsequent presence of a patent foramen ovale and paradoxical embolism clinically demonstrated the speed of action of the recombinant tissue plasminogen activator. The advantage of this class of medication when considering the treatment options for a PE in an acute setting is highlighted.     

Hypoxemia secondary to right-to-left interatrial shunt through a patent foramen ovale in a patient with an elevated right hemidiaphragm

Though uncommon, right-to-left shunt through a patent foramen ovale with normal right-side pressure and with a normal interatrial pressure gradient has been reported. The speculated pathophysiology is attributed to directional blood flow streaming from the vena cava to the left atrium. Hypoxemia secondary to right-to-left shunt with normal pulmonary artery pressure has been extensively documented after right pneumonectomy. Five prior cases have documented hypoxemia secondary to a right-to-left shunt through a patent foramen ovale in the presence of an elevated right hemidiaphragm. This is the sixth documented case of right-to-left shunt through a patent foramen ovale in the presence of an elevated right hemidiaphragm with a similar presentation in which closure of the patent foramen ovale resulted in resolution of hypoxemia.     

Right-to-left interatrial shunt in ARDS: dramatic improvement in prone position

The mechanisms leading to shunting through a patent foramen ovale include high right-sided cardiac pressures and respiratory factors due to mechanical ventilation and also anatomical changes in the right atrium as described in the platypnea-orthodeoxia syndrome. We report a patient with the adult respiratory distress syndrome (ARDS) who had a right-to-left atrial shunt which decreased in the prone position, after which oxygenation improved. The patient was admitted to the intensive care unit because of ARDS due to an invasive fungal infection. He had a history of chronic lymphocytic leukemia and paradoxical embolisms through a patent foramen ovale. Despite mechanical ventilation and antifungal treatment he developed severe ARDS. He was therefore turned to the prone position. Blood gas values improved dramatically (arterial oxygen tension/fractional inspired oxygen ratio increasing from 59 to 278 torr). Transcranial Doppler sonography was performed with bubble study, which confirmed a massive right-to-left shunt in the supine position and which instantaneously decreased in the prone position. This case suggests that a decrease in right-to-left shunt in patients who have a patent foramen ovale could partly explain the improvement in hypoxemia in the prone position. Received: 14 September 1998 Accepted: 3 February 1999     

Giant thrombus trapped in foramen ovale with pulmonary embolus and stroke.

We describe the case of a young man who, while he was in coma because of a traffic accident, had first a pulmonary embolus and immediately afterwards had a systemic (cerebral) embolus. A transesophageal echocardiographic image revealed a giant thrombi trapped in foramen ovale protruding in right and left ventricles, diagnosing, thus, a paradoxical embolism. The relationship between patent foramen ovale and pulmonary embolism has been reported in some series. Elevated right-chamber pressure caused by pulmonary hypertension could favor the establishment of a right-to-left shunt, causing, in some cases, paradoxical embolisms. We review the clinical implications.     

Patent foramen ovale presenting as platypnea-orthodeoxia: diagnosis by transesophageal echocardiography.

Platypnea-orthodeoxia is a rare syndrome that is often associated with interatrial shunting through a patent foramen ovale or atrial septal defect. We describe the case of a 65-year-old woman with progressive dyspnea and hypoxia when standing and walking, which was relieved by assuming the recumbent position. The diagnosis was confirmed by tilt-table transesophageal echocardiography demonstrating a large right-to-left shunt through a patent foramen ovale while the patient was in a semiupright position and no significant shunt while in a recumbent position. This case demonstrates that platypnea-orthodeoxia caused by a patent foramen ovale can be clearly demonstrated by the technique of contrast transesophageal echocardiography performed on a tilt table.     

Paradoxical air embolism successfully treated with hyperbaric oxygen

The use of the central venous catheter may be complicated by air embolism when central venous pressure is subatmospheric and the catheter is open to the surrounding air. Paradoxical air embolus occurs when the gas bubbles are able to traverse a right to left shunt, gaining access to the systemic arterial circulation causing ischemic symptoms in end organs. In this article, a case of a patient with an unknown patent foramen ovale through which air entered the arterial circulation resulting in obtundation and stroke after inadvertent manipulation of a Hickman catheter is presented. The physiology, clinical manifestations, and management strategies are also discussed.     

Acute myocardial infarction caused by paradoxical coronary embolization in a patient with a patent foramen ovale

We describe the case of a young woman without cardiac risk factors who had an acute inferoapical myocardial infarction. Coronary angiographic appearance was consistent with thrombus in the distal left anterior descending coronary artery. A patent foramen ovale with moderate right-to-left shunting after the Valsalva maneuver was detected by contrast transesophageal echocardiography. No other cardioembolic source was identified. Paradoxical embolization through a patent foramen ovale is a rare phenomenon, which appeared to have resulted in myocardial infarction in this patient.     

Differential diagnosis between patent foramen ovale and pulmonary arteriovenous fistula in two patients with previous cryptogenic stroke caused by presumed paradoxical embolism.

Development of improved devices for interventional closure of atrial septal defect and patent foramen ovale increased the number of adult patients who are being referred for transcatheter closure. We report two cases that were scheduled for patent foramen ovale closure because of a right-to-left atrial shunt detected at contrast transesophageal echocardiography in another institution and that were found to have pulmonary arteriovenous fistulas. Embolization of pulmonary arteriovenous fistulas was carried out successfully by transcatheter technique.     

右心声学造影联合房颤鉴别评分可提高对心源性脑梗死的预测价值

目的  探究右心声学造影联合房颤鉴别评分（STAF）对心源性脑梗死（CE）预测价值。方法  回顾性分析2017年8月~2021年8月医院收治149例CE患者及93例非心源性脑梗死（NCE）患者资料,分别作为CE组与NCE组。患者均接受右心声学造影及STAF,比较两组患者右心声学造影结果及STAF,分析右心声学造影联合STAF对CE的预测价值;CE患者随访1年,评估CE患者预后情况,分析CE患者预后影响因素。结果  CE组患者1级+2级+3级右向左分流分级、卵圆孔未闭阳性率、卵圆孔长径、分流口内径均高于NCE组（P < 0.05）;CE组患者STAF高于NCE组患者（P < 0.05）;ROC曲线显示右向左分流分级、卵圆孔未闭阳性率、卵圆孔长径、分流口内径、STAF用于CE预测曲线下面积分别为0.582、0.570、0.679、0.808、0.750,各指标联合AUC值为0.905;单因素与多元Logistic回归分析显示房颤、总胆固醇、纤维蛋白原不是CE患者预后影响因素（P > 0.05）,入院时NIHSS评分、卵圆孔未闭阳性率、卵圆孔长径、STAF是CE患者预后影响因素（P < 0.05）。结论  右心声学造影联合STAF有助于提高心源性脑梗死预测价值。     

Sildenafil to facilitate weaning from inhaled nitric oxide and mechanical ventilation in a patient with severe secondary pulmonary hypertension and a patent foramen ovale

We describe the case of a woman who presented to the intensive care unit with acute respiratory failure that required mechanical ventilation. She had severe pulmonary hypertension secondary to interstitial lung disease, and her history included sarcoidosis and tuberculosis. She was dependent on inhaled nitric oxide (INO) to maintain safe arterial oxygen saturation and could not be weaned from mechanical ventilation. Echocardiography revealed a patent foramen ovale with substantial right-to-left shunt, which probably contributed to her hypoxemia. Sildenafil enabled weaning from INO and substantially reduced the flow through the patent foramen ovale. She was successfully extubated and discharged home. To our knowledge, this is the first report of weaning from INO and mechanical ventilation in a patient with both severe secondary pulmonary hypertension and a right-to-left shunt through a patent foramen ovale.