Cerebral symptoms in pulmonary arteriovenous fistula. A result of paradoxical emboli (?)

Thalamic abscess in a patient with hereditary hemorrhagic telangiectasia successfully treated with an empiric antibiotic regime: case report and review of the literature

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disease associated with neurological complications, including cerebral abscesses (CA). They tend to be unique, supratentorial and lobar. While the surgical intervention is a rule of thumb when treating and diagnosing the etiology of these lesions, this is not always possible due to dangerous or inaccessible locations. We report the case of a patient solely treated with empiric antibiotics without stereotaxic intervention and satisfactory results.

CASE PRESENTATION

We present the case of a 21-year-old patient with a right thalamic abscess due to HHT and pulmonary arteriovenous malformations, previously embolized, treated solely with antibiotics. At first, we contemplated the possibility of a stereotaxic biopsy, but the high-risk location and the fact that our patient received a previous full course of antibiotic treatment (in another center), made us discard this intervention because of the low diagnostic yield. We started an empiric antibiotic regime. We followed up very closely the clinical and radiological evaluation the next weeks, adjusting our antibiotic treatment when necessary. The results were favorable from both the radiological and clinical aspects and 6 months after the diagnosis the images show its almost complete disappearance.

CONCLUSION

Carefully tailored antibiotic-only regime and vigilance of its adverse effects and close radiological following is a good treatment approach when surgery is not an option.

Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu disease) complicated by pulmonary arteriovenous fistula and brain abscess

A man who developed two brain abscesses was later found to have hereditary hemorrhagic telangiectasia with a pulmonary arteriovenous fistula. Brain abscess is a known complication of pulmonary arteriovenous fistulas. About 15% of patients with hereditary hemorrhagic telangiectasia develop such a fistula during their lives. Surgical resection of pulmonary arteriovenous fistulas is recommended because of the risk of severe neurological sequelae.

Pulmonary arteriovenous malformation associated with necrotizing fasciitis of the thigh

Pulmonary arteriovenous malformation (PAVM) is a rare condition often associated with hereditary hemorrhagic telangiectasia. The association between PAVMs and brain abscesses has been previously reported, but abscesses at other locations are extremely rare. We present a 51-year-old woman with PAVM (without signs of hereditary hemorrhagic telangiectasia) and necrotizing fasciitis of her thigh and discuss the possible relationship between the 2 disorders.

Brain abscess and hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder that can lead to serious central nervous system complications including hemorrhage, ischemia, and infection. Symptoms can be mild, making diagnosis problematic. Fifty-three prior cases of HHT and brain abscess are described, in addition to two new cases. The clinical manifestations and current methods for diagnosis and management of patients with HHT are reviewed. Early recognition of HHT is important because screening in these patients and affected family members may help prevent complications. In addition, advancements in imaging, surgical techniques, antibiotics, and genetic testing may improve outcomes.

Migraines Linked to Intrapulmonary Right-to-Left Shunt

OBJECTIVE

To determine if there is an association between migraines and intrapulmonary right-to-left shunt.

BACKGROUND

Several studies have described an association between migraines and intracardiac right-to-left shunt.

METHODS

Patients with hereditary hemorrhagic telangiectasia (HHT) were retrospectively recruited from the Toronto Hereditary Hemorrhagic Telangiectasia Center Clinical Database. All patients had been prospectively, systematically asked about a history of migraines and systematically screened for pulmonary and cerebral arteriovenous malformations (AVMs). All patients with a definite diagnosis of HHT, assessed during a 2-year period (February 1997 to April 1999), were included. Univariate analyses and logistic regression were performed, for migraine as the dependent variable and the following independent variables: age, sex, pulmonary AVMs, and cerebral AVMs.

RESULTS

Of the 200 patients assessed during the 2-year period, 124 (62%) had a definite diagnosis of HHT and were included in the analysis. Eighty (65%) were females. Forty-seven (38%) of the HHT patients had a history of migraine, of whom 38 (81%) had migraine with aura. The prevalence of migraine was greater in patients with pulmonary AVMs (46%) compared to patients without pulmonary AVMs (33%), OR = 1.7 (0.8 to 3.6), though this did not reach statistical significance (P = .14). Pulmonary AVMs were significantly associated with migraine (OR = 2.4, 95% CI = 1.1 to 5.5, P = .04), after adjustment for age and sex, using logistic regression.

CONCLUSIONS

There is a significant association between intrapulmonary right-to-left shunt and migraine.

Clinical symptoms according to genotype amongst patients with hereditary haemorrhagic telangiectasia

BACKGROUND

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease, characterized by a wide variety of clinical manifestations, including epistaxis, gastrointestinal (GI) bleeding, pulmonary arteriovenous malformations (PAVMs) and neurological symptoms. HHT is a genetically heterogeneous disorder involving at least two loci; HHT 1 mapping to chromosome 9 q 34.1 (ENG) and HHT 2 mapping to chromosome 12 q 31 (ALK-1).

OBJECTIVE

To evaluate and describe the diversity of clinical manifestations in a Danish population of HHT patients with known HHT 1 or HHT 2 subtype.

DESIGN

Prospective clinical examination with genetic evaluation and follow-up.

SETTING

Investigation centre was Odense University Hospital. All HHT patients in the County of Fyn were included.

METHODS

HHT family members were invited to a clinical examination including registration of HHT manifestations, screening for PAVM and neurological evaluation. Blood tests were performed for analysis of disease-causing mutation, and clinical manifestations in the HHT subtypes were compared. The survival of the patients was studied in the follow-up period.

RESULTS

Included in the study were 73 HHT patients representing 18 families. In 14 of the families we identified a disease-causing mutation. Thirty-nine patients (from 10 families) had HHT1 and 16 HHT patients from four families had HHT2.

CONCLUSION

Amongst patients with HHT1 genotype the prevalence of PAVM was higher than amongst HHT patients with HHT2 genotype. HHT1 patients had experienced more severe GI bleeding than HHT2 patients. There was no significant difference in severity of epistaxis or age at debut. Finally the mortality over a 90-month observation period was not significantly increased.

Prevalence of pulmonary arteriovenous malformations (PAVMs) and occurrence of neurological symptoms in patients with hereditary haemorrhagic telangiectasia (HHT)

BACKGROUND

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease. HHT is characterized by a wide variety of clinical manifestations, including pulmonary arteriovenous malformations (PAVMs) and neurological symptoms.

OBJECTIVE

To estimate (i) the prevalence of PAVM, and (ii) the occurrence of neurological symptoms in a geographical well-defined population of HHT patients.

METHODS

HHT family members were invited to a clinical examination including registration of HHT manifestations, screening for pulmonary arteriovenous malformations and neurological evaluation. Two groups served as controls: (i) first-degree relatives without any signs of HHT; and (ii) age- and gender-matched controls.

SETTING

Odense University Hospital.

SUBJECTS

HHT patients identified in a cross-sectional family survey carried out in the County of Fyn, Denmark.

RESULTS

Included in the study were 169 HHT family members representing 24 families. They included both HHT patients and their first-degree relatives. The criteria of HHT were fulfilled in 75 participants; of these, 59 had a screening procedure performed, and PAVMs were demonstrated at pulmonary angiography (PA) in 18. Seven of the HHT patients had a history of cerebral stroke, compared with none of their healthy first-degree relatives.

CONCLUSION

The prevalence of PAVM was 24% amongst HHT patients. The study confirmed an increased prevalence of neurological symptoms amongst HHT patients; the odds ratio was estimated to be 7.6. In order to enable prevention of these complications, screening for PAVM should become an integral part of the medical care for HHT patients.

Pulmonary arteriovenous malformations: screening procedures and pulmonary angiography in patients with hereditary hemorrhagic telangiectasia

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a dominantly inherited disease with a high prevalence of pulmonary arteriovenous malformations (PAVMs). The first symptom of HHT may be stroke or fatal hemoptysis associated with the presence of PAVM.

OBJECTIVE

To evaluate different screening methods applied for the identification of PAVMs.

SETTING

Odense University Hospital.

SUBJECTS

HHT patients with positive findings on contrast echocardiography (CE) who participated in a screening investigation and underwent pulmonary angiography (PA).

METHODS

Different screening methods were evaluated against the results of PA. In a group of patients with positive findings on CE, we compared results of PA with the following: severity of dyspnea; results of pulse oximetry arterial oxygen saturation (SaO2) supine and upright; supine PaO2 in room air and while breathing 100% oxygen; size of arteriovenous shunt in supine position; chest radiograph; and intensity of contrast at CE.

RESULTS

PA was performed in 25 HHT patients with positive findings on CE, 15 of whom had PAVM. Embolization therapy was recommended in 12 patients, and 3 patients had small PAVMs not accessible for therapy. In 10 patients, PAVM could not be demonstrated at PA. The sensitivity and specificity calculated for the screening procedures are as follows: 53% and 90%, respectively, for SaO2; 60% and 100%, respectively, for chest radiograph; 73% and 80%, respectively, for PaO2 in room air; 100% and 40%, respectively, for PaO2 breathing 100% oxygen; and 64% and 80%, respectively, for shunt measurement.

CONCLUSION

Initial screening with CE followed by measurement of PaO2 while breathing 100% oxygen seemed to be the best screening procedure for identification of patients with PAVM. Screening with chest radiograph and pulse oximetry was shown to be insufficient.

Paradoxical embolism. An underrecognized problem

Despite reports of the clinical presentations and devastating consequences of paradoxical embolus (PDE) for more than a century, this diagnosis continues to be frequently missed. Because the prevalence of patent foramen ovale (PFO) is 27 to 35% in the normal population and the presence of deep vein thrombosis or pulmonary embolus may not be clinically obvious, a high suspicion for PDE is needed in the event of unexplained arterial occlusion. While contrast echocardiography and transcranial Doppler ultrasound have facilitated clinical recognition of PDE, the optimum approach to diagnosis requires clarification. Primary therapy for patients with PDE is anticoagulation, with thrombolytics considered in carefully selected individuals, but there is little published information regarding long-term treatment and outcomes. Prevention remains essential whenever possible. It is not yet defined whether prophylactic treatment of persons with recognized predispositions to PDE (eg, PFO and pulmonary hypertension) is beneficial.

Hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease) presenting with polymicrobial brain abscess. Case report

A 26-year-old man presented with expressive aphasia, weakness of the right arm, and anemia but there was no family history of hereditary hemorrhagic telangiectasia. Computerized tomography (CT) of the head demonstrated an enhancing left frontal mass, which was aspirated and on culture yielded multiple organisms. Pulmonary arteriovenous fistulae identified in both lungs by chest radiography, CT, and angiography were treated with coil embolization. Treatment of pulmonary arteriovenous fistulae and prolonged surveillance are necessary to prevent future neurological complications.

Pulmonary arteriovenous fistula: mechanical ventilation and hypoxemia

Pulmonary arteriovenous malformation (PAVM) is an uncommon congenital anomaly. As PAVM is a direct communication between branches of the pulmonary artery and vein, major disturbances in gas exchange can result. We present a patient with an unsuspected PAVM who came to our institution for drainage of a brain abscess. Arterial blood gas analysis during and after surgery demonstrated a large alveolar-arterial gradient for oxygen in the absence of any obvious pulmonary pathology while the patient was receiving positive pressure ventilation (PPV). Oxygenation improved considerably upon resumption of spontaneous ventilation. A diagnosis of PAVM was made subsequently. We conclude that positive pressure ventilation can worsen right to left shunting in patients with PAVM.

Paradoxical embolism: clinical presentation, diagnostic strategies, and therapeutic options

Thirty cases of paradoxical embolism are reviewed to consolidate clinical presentations and common predisposing factors. The presence of patent foramen ovale in the great majority of these patients in association with maneuvers that transiently elevate right atrial pressure is emphasized in relation to the pathophysiology of the disorder. Contrast echocardiography with provocative maneuvers such as Valsalva and cough are discussed and treatment options highlighted. The underdiagnosis of paradoxical embolism is discussed, and its potential importance in other more common vascular diseases addressed.

Concomitant pulmonary and cerebral arteriovenous fistulae

The previously unreported occurrence of concomitant pulmonary and cerebral arteriovenous fistulae was found in an individual with severe neurologic complications. Both polycythemia and paradoxical embolization were implicated in the genesis of the cerebral symptoms while the cerebral fistulae were asymptomatic. An improved method of therapeutic embolization was used to treat the pulmonary lesions, avoiding surgical resection.

Arteriovenous fistula of the lung

Pulmonary arteriovenous fistula is an unusual but not rare abnormality with more than 450 cases reported in the literature. Studies during the last 30 years have established the effective prevention of morbidity and relief of symptoms by operative excision. During the last 25 years, the Vanderbilt University Affiliated Hospitals have seen 7 patients with pulmonary arteriovenous fistula. This experience prompted a review of the literature. Particular emphasis is placed on current means of diagnosis and therapy.

Cerebral emboli of paradoxical origin

A diagnosis of paradoxical cerebral embolus (PCE) was made in five patients aged 31 to 62 years who sustained eight cerebral ischemic events. No patient had evidence of primary carotid system or left heart disease. A probe-patent foramen ovale was the presumed mechanism in four patients, and an unsuspected congenital atrial septal defect was found in the fifth patient. Clinically apparent pulmonary emboli or venous thrombosis preceded the cerebral event in only one instance. Review of the literature reveals a high mortality with PCE. However, careful clinical search for this lesion may be rewarding: four of our five patients survived. One should consider PCE in any patient with cerebral embolus in whom there is no demonstrable left-sided circulatory source. This principle applies particularly if there is concomitant venous thrombosis, pulmonary embolism, or enhanced potential for venous thrombosis due to, for example, morbid obesity, use of hormonal birth control pills, prolonged bed rest (especially postoperatively), or systemic carcinoma.

Pulmonary arteriovenous fistulas

During the 20-year-period 1959-78, 7 patients with pulmonary arteriovenous fistula were treated at the Department of Thoracic and Cardiovascular Surgery. There were 5 men and 2 women, with a mean age of 26 (14-47) years. Cyanosis with elevated haematocrit was present in 4, dyspnoea in 4, neurological signs in 3 (including one brain abscess and one hemiplegia). Systolic hum was audible in 3 cases. Three patients had the hereditary type of the disease (Rendu-Osler-Weber) with telangiectasiae also elsewhere in the body. The calculated right-to-left shunt varied from 14 to 56 per cent of the cardiac output. The treatment was lobectomy in all cases (4 upper lobe, one middle lobe and 2 lower lobe resections). The patient with a brain abscess underwent craniotomy prior to lobectomy and developed epilepsy necessitating anticonvulsive treatment. The other patients had an uneventful recovery with relief of the symptoms. During the follow-up time (2-20 years), one patient (with hemiplegia) died of myocardial infarction 10 years after the operation. The others were doing well. It is concluded that the safest way to treat a pulmonary arteriovenous fistula is to operate as soon as it has been detected in order to prevent the complications so often associated with the disease.

Neurological manifestations of hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease): report of 2 cases and review of the literature

Two cases of hereditary hemorrhagic telangiectasia (HHT) with neurological involvement are presented. One patient had multiple vascular malformations including telangiectasias of the brain, medulla, and spinal cord and a berry aneurysm of the internal carotid artery; she also had a large cerebellar abscess, presumably reflecting the presence of a pulmonary arteriovenous fistula. The second patient had an idiopathic subarachnoid hemorrhage. In more than 200 reported patients with HHT involving the nervous system, 61% had lesions seondary to a pulmonary arteriovenous fistula (cerebral hypoxemia, paradoxical and septic emboli, and brain abscess). The findings emphasize the need for early surgical correction of such fistulas. In 36% of the patients with neurological involvement and HHT, vascular malformations of the brain and spinal cord were documented, and in 3%, portal-systemic encephalopathy was noted. Multiple lesions were frequent. HHT should be considered a generalized vascular dysplasia (universal or systemic angiomatosis), and not simply a benign mucocutaneous disease.

Pulmonary embolism and intracardiac shunt: a unique indication for operation

Pulmonary embolism with right-to-left intracardiac shunt presents a special problem for the clinician. A review of the literature and 4 personal cases, all diagnosed antemortem, are presented. On the basis of this information certain conclusions are drawn, and we suggest the problem to be a unique indication for the consideration of surgical intervention.

Cine angiographic diagnosis of patent foramen ovale in paradoxical embolism,

A case of paradoxical embolism is presented in which the antemortem diagnosis was facilitated by a new simple angiographic technique that demonstrated a patent foramen ovale. An additional 14 patients were studied by this technique, and one had a patent foramen ovale. The mechanism of reversal of the normal intraatrial pressure gradient and subsequent right to left shunt through a patent foramen ovale is discussed. This angiographic technique may be readily applied in any diagnostic catheterization laboratory and complements existing methods for detecting patency of the foramen ovale in patients with suspected paradoxidal embolism.

Pulmonary arteriovenous fistula. A review

A successfully treated case of an arteriovenous fistula of the lung is reported. An exhaustive review is made of the pertinent literature and the pathophysiology, embryology, clinical aspects, diagnosis and treatment are discussed.