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G P Anzola

Publications and source records attributed to G P Anzola.

At least 19 recordsLinked to original sources
PubMed2006

Silent brain embolism during transcatheter closure of patent foramen ovale: a transcranial Doppler study.

The aim of this report is to quantify the amount of spontaneous microembolism detected in brain vessels by transcranial Doppler (TCD) during transcatheter closure of right-to-left shunt (RLS). We examined 29 patients who had had a stroke or a transient ischaemic attack (17 females and 12 males; mean age 45+/-15 years). They all underwent TCD monitoring during the procedure and microembolic signals (MES) were recorded. Detection of MES was distributed as follows: during femoral catheterisation in 8 patients (25%), during atrial catheterisation in 5 patients (17%), during transeptal crossing in 14 patients (48%), during left disc opening in 28 patients (96%) and during right disc opening in 7 patients (24%). The highest rates of MES were observed during left disc opening and less during transeptal crossing with an average count of 31 (range 3-135) and 3 (range 1-18) respectively. Brain embolism occurs throughout the procedure after femoral catheterisation for PFO closure. Our results indicate that the majority of MES reached the brain during the opening of the left disc in the left atrium: 28/29 patients exhibited MES with an average of 31 (3-135), thus supporting the notion that gas embolism accounted for the findings.

Adult↗
PubMed2004

Does transcatheter closure of patent foramen ovale really "shut the door?" A prospective study with transcranial Doppler.

BACKGROUND AND PURPOSE: Transcatheter closure of patent foramen ovale (PFO) is increasingly being performed and monitored with transthoracic or transesophageal echocardiography, whereas contrast-enhanced transcranial Doppler (ce-TCD), which probably represents the most suitable tool to quantify right-to-left shunt (RLS) in the brain vessels, has been systematically overlooked. Our goal is to prospectively assess efficacy and safety of PFO transcatheter closure using ce-TCD. METHODS: A total of 140 consecutive patients (mean age, 46+/-13 years; male/female ratio, 63/77) with PFO-related large RLS and no other recognized cause of focal cerebral ischemia underwent transcatheter closure. TCD was done preoperatively and 1 month after the procedure in all patients, after 3 months in 120, after 6 months in 112, and after 1 year in 104 patients. RESULTS: Implantation was successful in all patients. During Valsalva strain, a large shunt was still detectable in 31 of 140 (22%), 15 of 120 (13%), 9 of 112 (8%), and 9 of 104 (9%) patients at the 1-, 3-, 6-, and 12-month visits, respectively. Periprocedural and postprocedural complications included atrial fibrillation in 8% and scintillating scotomata in 6% of patients. During the 1-year follow-up period, only 1 transient ischemic attack was recorded in a patient with paroxysmal atrial fibrillation and complete PFO closure. CONCLUSIONS: Transcatheter PFO closure in patients with cryptogenic stroke and large RLS may be less successful than reported previously. TCD appears the ideal tool to follow up the closure process and to identify early, during follow-up, those patients who will be left with a significant shunt. Atrial fibrillation is more common than believed previously and may underlie the occurrence of further cerebrovascular events despite complete PFO closure. Irritative visual phenomena may occur as a consequence of nickel toxicity.

Adult↗
PubMed2003

Transcranial Doppler and risk of recurrence in patients with stroke and patent foramen ovale.

The importance of patent foramen ovale (PFO) in stroke of unknown cause remains disputed, as PFO may be present in up to 20% of normal people and in a high proportion of patients with non-vascular disorders. Recent evidence suggests that the amount of right-to-left shunt (RLS) may be the crucial factor for stroke occurrence and relapse. The aim of the study was to assess predictors of recurrence in PFO-related stroke patients with particular emphasis on amount of shunting. Patients less than 61 years old who had been admitted for a PFO-related stroke within the previous 5 years, were re-evaluated on a follow-up visit. The clinical syndrome, residual disability, vascular risk factors and number of relapses as the index event were assessed. RLS sizing was semi-quantitatively performed with saline-enhanced transcranial Doppler (TCD), by assuming a cut-off of more or less 10 bubbles recorded in the cerebral vessels as a criterion to discriminate large versus small shunt, respectively. Thereafter patients were prospectively followed-up for a median time of 23 months. Total follow-up was 61 months. Fifty-nine patients (M/F = 23/36, mean age 43 +/- 13) were studied. Overall there were 23 relapses in 13 patients. The amount of shunting was the only significant independent variable associated with relapse: at the end of the follow-up period the recurrence rate was 0.66 and 8.2% per patient per year in patients with small and large shunt, respectively. This difference was statistically significant (chi2 = 10.39, P = 0.0012; OR 17.05, 95% CI 2.10-755.22). In patients with PFO-related stroke, the amount of RLS as assessed with TCD is the only independent predictor of relapse. PFO sizing is mandatory in patients with PFO.

Female↗
PubMed2003

Transient global amnesia: a clinical and sonographic study.

BACKGROUND: The aetiology of transient global amnesia (TGA) is still unknown. The aim of this study was to identify potential risk factors for TGA, vascular risk factors, the role of patent foramen ovale (PFO) and of retrograde jugular venous flow. METHODS: 138 subjects entered the study, including 48 patients with TGA, 42 age-matched patients with transient ischaemic attack (TIA) and 48 controls. PFO was studied by contrast transcranial duplex sonography. Retrograde jugular venous flow was tested with air contrast ultrasound venography (ACUV). RESULTS: TGA patients and controls showed a lower prevalence for vascular risk factors than TIA patients. No statistical difference was found between the 3 groups with regard to PFO. ACUV detected jugular valve incompetence in 72.9% TGA, 35.7% TIA and 39.5% controls (TGA vs. TIA and TGA vs. controls p < 0.01). CONCLUSIONS: TGA patients have fewer vascular risk factors than TIA patients. Paradoxical embolism due to PFO as a cause of TGA is not confirmed in our study. Cerebral venous hypertension due to incompetence of the internal jugular valve may play a role in the pathogenesis of TGA.

Amnesia, Transient Global↗
PubMed2001

Transcranial Doppler in the diagnosis of cardiac patent foramen ovale.

Right-to-left shunt due to patent foramen ovale is a well-established risk factor for ischemic stroke, especially in young subjects and in patients with cryptogenic stroke. We report a detailed method for the diagnosis of a right-to-left shunt by means of transcranial Doppler as established at a recent consensus conference, and review the literature on the indications for the test.

Brain Ischemia↗
PubMed1999

Potential source of cerebral embolism in migraine with aura: a transcranial Doppler study.

BACKGROUND: The recently found association between patent foramen ovale (PFO) and transient global amnesia (TGA) has suggested that paradoxical microembolization in the terminal vertebrobasilar territory might underlie at least some TGA cases. Migraine with visual aura is another paroxysmal disturbance in which a sudden dysfunction of cortical areas fed by the terminal branches of the basilar artery is believed to trigger the attack. Therefore we investigated the prevalence of PFO in a consecutive unselected cohort of migraine patients. OBJECTIVE: To investigate the prevalence of PFO in a consecutive unselected cohort of migraine patients to search for a possible mechanism for the reported association of migraine with stroke. METHODS AND RESULTS: A total of 113 patients, consecutively referred by the Headache Outpatient Clinic for migraine with aura (MA+, mean age 34+/-12 years) were compared with 53 patients with migraine without aura (MA-, mean age 36+/-13 years) and with 25 age-matched nonmigraine subjects (mean age 31+/-10 years) selected from the hospital staff. PFO was assessed with transcranial Doppler sonography with IV injection of agitated saline, a technique that is 90% sensitive and 100% specific. The prevalence of PFO was 48% (54/113) in MA+ patients, 23% (12/53) in MA- patients, and 20% (5/25) in control subjects. The difference between MA+ and MA- patients was significant (odds ratio [OR] = 3.13, 95% confidence interval [CI] = 1.41 to 7.04, chi2 = 9.52,p = 0.002) as was the difference between MA+ patients and controls (OR = 3.66, 95% CI = 1.21 to 13.25, chi2 = 6.46, p = 0.01), whereas MA- patients did not differ from controls (OR = 1.17, 95% CI = 0.32 to 4.45, chi2 = 0.07). MRI was negative in 22 MA+ and 8 MA- patients. CONCLUSIONS: Patency of the foramen ovale is associated with migraine with aura but not with migraine without aura. The increased risk of stroke found in epidemiologic studies in patients with migraine with aura may be explained by an increased propensity to paradoxical cerebral embolism.

Adolescent↗
PubMed1998

Fatal familial insomnia in a new Italian kindred.

The authors report a new kindred with fatal familial insomnia (FFI)--an inherited prion disease. The propositus had behavioral, sleep, cognitive, and motor impairment associated with thalamic and olivary atrophy. Spongiosis was confined to the parahippocampal gyrus. Protease-resistant prion protein (PrP(res)) was present with widespread distribution. The propositus fits the histopathology of FFI with similar clinical duration and confirms the role of disease duration in determining histopathology and PrP(res) distribution in FFI.

Age of Onset↗
PubMed1996

[Diagnosis and follow-up of 330 patients admitted for syncope in the Department of Cardiology and Neurology. How important is an interdisciplinary study?].

Many mechanisms of different nature-hemodynamic, metabolic and reflex-may cause syncope. We have studied all patients referred for syncope to the Divisions of Cardiology and Neurology of our Hospital, focusing five end-points: standardize a diagnostic protocol; evaluate the diagnostic value of the different tools in the diagnosis of syncope; evaluate the causes of syncope in our patients; value the importance of systematic cardiological-neurological co-operation in these patients; observe the prognosis of patients with syncopal attacks. We have studied 330 patients referred to our Divisions for syncopal attacks (239 in Cardiology and 91 in Neurology) with a protocol organized in 4 steps of increasing levels of complexity: step 1: history, clinical examination, standard electrocardiogram, carotid sinus massage, chest radiography, neurological and cardiological examination; step 2: two-dimensional Doppler echocardiography, dynamic 24-72 hour ECG, standard electroencephalogram (EEG), head-up tilt-table test; step 3: EEG after sleep deprivation, computed tomography, Doppler evaluation of carotid flows, transesophageal electrophysiologic study (EPS); step 4: Oxford test for 24-hour evaluation of arterial blood pressure, intracavitary EPS. We have found in 165 patients (50%) a cardiac syncope, in 78 (23.6%) a reflex syncope, in 43 patients (13%) a syncope of different origin ("non cardiac-non reflex") and in 44 patients (13.4%) we have not been able to find a cause of patient's syncopal attacks. We have established a diagnosis in 148 patients (51.7% of diagnoses) with step 1 examinations, in 98 cases (34.2%) with step 2, in 33 (11.5%) with step 3 and in 7 (2.5%) with step 4 examinations. One hundred-twenty three patients - or relatives of died patients-(37.3%) have answered our follow-up questionnaire (mean follow-up 54.85 +/- 13.73 months, range 36-78 months). Among them, patients with cardiac syncope have had a mortality rate of 18.57%, those with reflex syncope of 7.69%, those with "non cardiac-non reflex" syncope of 7.14%. No patients with syncope of unknown origin died. Our study demonstrates that in the evaluation of patients with syncope, the simplest diagnostic tools are of great value: in fact we have obtained 86% of the diagnoses with the first 2 steps examinations. Furthermore, our study confirms that cardiac syncope has a higher mortality rate compared to other forms of syncope. Co-operation between our Divisions has not been very useful in increasing the number of diagnosed cases, but it has allowed to correctly and rapidly direct our attention toward one form of syncope so that we have been able to speed up the diagnostic process.

Adolescent↗
PubMed1995

Transcranial Doppler sonography and magnetic resonance angiography in the assessment of collateral hemispheric flow in patients with carotid artery disease.

BACKGROUND AND PURPOSE: The aim of this investigation was to compare the respective efficacy of transcranial Doppler sonography (TCD) and magnetic resonance angiography (MRA) for the assessment of intracranial hemodynamics in patients with extracranial occlusion or severe stenosis of the internal carotid artery (ICA). METHODS: Twenty-five patients with unilateral ICA occlusion (n = 20) or tight stenosis (n = 5) demonstrated by duplex scanning or angiography were studied with both TCD and MRA. Three-dimensional time-of-flight MRA was used for the evaluation of extracranial-intracranial ICAs. Collateralization through the circle of Willis was investigated by means of selective two-dimensional MRA with presaturation of the carotid siphon, ophthalmic artery, or basilar artery. TCD was performed according to published standards: Anterior, middle, and posterior cerebral arteries were insonated through the temporal window, and carotid siphon and ophthalmic artery were assessed through a transorbital approach. Collateralization through the anterior circle of Willis was assumed if anterior cerebral artery flow was reversed, through the external carotid artery if ophthalmic artery flow was reversed, and through the basilar artery if the ratio of ipsilateral to contralateral posterior cerebral artery velocity was greater than 50%. TCD and MRA were performed by different investigators unaware of the results obtained with the other technique. RESULTS: In every case time-of-flight MRA demonstrated the ICA occlusion or stenosis. There was an excellent correlation (kappa = 0.64) between TCD and MRA in assessing the hemodynamic contribution of the anterior part of the circle of Willis, whereas MRA was unable to detect the anastomotic pathway of the ophthalmic artery (kappa = 0.32). The contribution of the posterior communicating artery was difficult to assess with both techniques, but in three cases only MRA showed unequivocal evidence of collateralization. In three cases of middle cerebral artery stenosis TCD was superior to MRA in demonstrating the patency of the vessel. CONCLUSIONS: TCD and MRA should be considered complementary techniques. Combining the findings of both examinations may help to better understand the changes in intracranial hemodynamics produced by extracranial carotid occlusion. The contribution of the ophthalmic pathway, although important for the intraorbital structures, is probably of limited functional significance to the hemispheric blood supply.

Adult↗
PubMed1994

Isolated accessory nerve palsy of unusual cause.

We report the case of a 23 year old male patient who presented for an isolated left accessory nerve palsy which had appeared one year before. Neuroradiological investigations showed that the causative pathology was a giant saccular aneurysm of the intracranial left vertebral artery. Three months after diagnosis, signs of bulbar palsy rapidly developed. An emergency intra-arterial embolization was then attempted, which led to complete recovery except for the accessory nerve palsy which remained unchanged. We conclude that, in cases of apparently isolated accessory nerve palsy, neuroradiological investigations should include the posterior fossa.

Accessory Nerve↗
PubMed1993

Abnormal photoreactivity in ictal migraine: reversal by sumatriptan.

The reactivity of posterior cerebral artery (PCA) to light stimulation was studied with transcranial Doppler in 9 migraine patients (5 with aura, 4 without aura) within six hours of the onset of headache (mean 115 +/- 78 minutes). The PCA mean flow velocity was recorded while the patient was in the dark and with the eyes closed and, subsequently, while the light was on and with the eyes open. Both symptomatic and asymptomatic sides were recorded. The same test was repeated thirty minutes after injection of sumatriptan 6 mg subcutaneously and again on the third day after cessation of the attack. Photoreactivity was calculated, for each side and for each situation, as percent relative increase of the corresponding averaged mean flow velocity recorded in darkness. The results showed that, although absolute flow velocities were not statistically different between sides and situations, photoreactivity was significantly increased on the symptomatic side during attacks (+28% vs 15% respectively). After sumatriptan, photoreactivity became symmetrical and (nonsignificantly) inferior to the values recorded in the interictal period. These findings suggest that, during headache, peripheral resistance branches of PCA on the symptomatic side are hypersensitive to vasodilatory stimuli. This could represent the counterpart of the clinical scotomata and photophobia commonly experienced by migraine patients during attacks.

Adolescent↗
PubMed1993

Early prognostic factors in ischemic stroke. The role of protein C and protein S.

BACKGROUND AND PURPOSE: Protein C and protein S have been found reduced in some patients with ischemic cerebrovascular diseases, but the relevance of this finding for prognosis is unsettled. METHODS: In 43 consecutive patients admitted over 6 months for acute ischemic stroke, protein C and free protein S were evaluated on admission, and at 2 and 6 months after stroke. Excluded were all patients with known causes liable to reduce the levels of protein C, free protein S, or both. RESULTS: In 14% of patients, abnormally low levels of protein C were found at entry. In comparison to the remaining sample, this group had a significantly lower initial score on the Barthel and Canadian neurological scales, a higher prevalence of emboligenic cardiac diseases, and had a higher mortality at 6 months. No statistical difference was found for the other vascular risk factors. Eight patients (18.4%) had abnormally low levels of free protein S at entry. In comparison to the remaining sample, there was no statistical difference in the severity scores, prevalence of emboligenic cardiac diseases, mortality, or vascular risk factors. CONCLUSIONS: These findings suggest that low levels of protein C in the acute stroke reflect the massive activation of coagulation factors and are predictive of adverse outcome, whereas the significance of low levels of free protein S remains to be clarified.

Adult↗
PubMed1992

The spatial distribution of attention in S-R compatibility.

In certain choice reaction time experiments the subjects, although not specifically instructed to do so, perform a parcellation of space into right and left components. Previous research has shown that when the stimulus locations are marked on the screen, the subdivision of space into right and left halves is bound to the point where the subject has been instructed to focus selective attention. It is not known whether, in the absence of specific instructions, subjects are able to focus selective attention between stimulus locations when no marker is present. We tried to clarify this problem by introducing a 'probe' stimulus that could map the spatial distribution of attention in subjects engaged in a compatibility task. The results suggest that, in the absence of visual cues marking the stimulus positions, attention is kept in the disengaged modality before the presentation of the stimuli. In this state of disengagement a powerful tendency to orient to the rightmost side of the display, within each visual field, is apparent. Various interpretations of this finding are discussed.

Adolescent↗
PubMed1992

Interhemispheric communication following unilateral cerebrovascular lesions.

39 patients with a single small cerebrovascular lesion (20 in the right, 19 in the left hemisphere) were subjected to a simple reaction time (RT) task with visual stimuli flashed to the visual field either ipsilateral or contralateral to the cerebral lesion. The subject responded always with the ipsilateral hand. The crossed-uncrossed difference (CUD), i.e. the RT when both stimulus and response occur on the same side minus the RT when stimulus and response occur on opposite sides, is assumed to assess the transit time of information through callosal fibers, and in normal people is about 3-5 msec. In our patients the mean CUD, expressed as the difference between contralateral and ipsilateral responses, was 20 msec. Patients with parietal lesions had still longer CUDs, 37 msec on the average. There was no statistical difference in CUDs between right and left brain-damaged patients. The CUD in brain-damaged patients was of the same order of magnitude as that found in acallosal or split-brain patients. Nonetheless, the present findings are interpreted as reflecting the intrahemispheric rather than the interhemispheric delay in information transmission, with the possible additive effect of an asymmetrical orienting of attention.

Brain↗