Further evidence for the topography and connectivity of the corpus callosum: an FMRI study of patients with partial callosal resection.

BACKGROUND AND PURPOSE: This functional MRI study was designed to describe activated fiber topography and trajectories in the corpus callosum (CC) of six patients carrying different degree of partial callosal resection. METHODS: Patients receiving gustatory, tactile, and visual stimulation according to a block-design protocol were scanned in a 1.5 Tesla magnet. Diffusion tensor imaging (DTI) data were also acquired to visualize spared interhemispheric fibers. RESULTS: Taste stimuli evoked bilateral activation of the primary gustatory area in all patients and foci in the anterior CC, when spared. Tactile stimuli to the hand evoked bilateral foci in the primary somatosensory area in patients with an intact posterior callosal body and only contralateral in the other patients. Callosal foci occurred in the CC body, if spared. In patients with an intact splenium central visual stimulation induced bilateral activation of the primary visual area as well as foci in the splenium itself. CONCLUSION: Present data show that interhemispheric fibers linking sensory areas crossed through the CC at the sites where the different sensory stimuli evoked activation foci, and that topography of callosal foci evoked by sensory stimulation in spared CC portions is consistent with that previously observed in subjects with intact CC.

Effects of immune system status on long-term results of cardiac resynchronization therapy.

AIM: Cardiac resynchronization therapy (CRT) is an effective therapy for patients with reduced systolic function and enlarged QRS. Recently, some Authors have demonstrated that the presence of positive antinuclear antibodies (ANAs) may play a role in the development of heart failure in a population of patients implanted with PM. METHODS: We investigated the effect of positive ANAs in 90 patients (mean age 71±8 years) implanted with a CRT device in our Centre between May 2010 and June 2013. To assess for immunologic contribution to CRT outcome, patients were divided into positive and negative ANAs (ANA +, ANA -), considering as positive patients with an ANAs dilution > 1:80. The primary endpoint was constituted by a combined endpoint of death or first hospitalization for heart failure; secondary endpoints were constituted by: 1) incidence of first hospitalization for heart failure; and 2) total cause mortality. RESULTS: After a mean follow-up of 1200 days, primary endpoint occurred in 11 patients (30%) of ANA+ group and in 8 patients (15.1%) of ANA-group. The significant difference is due to difference in heart failure events (27% vs. 11.3%, P<0.05), whilst difference in total mortality did not reach statistical significance (10.8% vs. 3.8%). CONCLUSION: Immune status seems to play a role in patients with congestive heart failure. If this immunological alteration is a determinant or a consequence of heart failure remains unclear.

Diffusion tensor tracking of callosal fibers several years after callosotomy.

Diffusion tensor imaging (DTI) can provide more detailed in vivo information on the structural preservation of transected white matter tracts than conventional imaging methods. Here we show for the first time tracks of severed callosal fibers up to 17 years from resection. Five patients subjected to complete or partial callosotomy several years before the study were examined with DTI and compared to a normal control. Transected fibers were traced in all patients and were more clearly visible in the anterior and posterior parts than in the middle of the commissure. These findings suggest that microstructural changes persist for many years in the severed fibers, as also reflected by fractional anisotropy and apparent diffusion coefficient values, enabling a reconstruction of the longitudinal organization of severed central tracts that could not be achieved with previous techniques.

Contribution of the corpus callosum to bilateral representation of the trunk midline in the human brain: an fMRI study of callosotomized patients.

Human brain studies have shown that the cutaneous receptors of trunk regions close to the midline are represented in the first somatosensory cortex (SI) of both hemispheres. The present study aims to establish whether in humans, as in non-human primates, the bilateral representation of the trunk midline in area SI depends on the corpus callosum. Data were obtained from eight callosotomized patients: three with complete callosal resection, one with a partial posterior resection including the splenium and the callosal trunk, and four with partial anterior resections sparing the splenium and in one case also the posterior part of the callosal trunk. The investigation was carried out with functional magnetic resonance imaging. Unilateral tactile stimulation was applied by rubbing ventral trunk regions close to the midline (about 20 x 10 cm in width) with a soft cotton pad (frequency 1 Hz). Cortical activation foci elicited by unilateral stimulation of cutaneous regions adjacent to the midline were detected in the contralateral post-central gyrus (PCG), in a region corresponding to the trunk ventral midline representation zone of area SI, as described in a previous study of intact subjects. In most patients, activation foci were also found in the ipsilateral PCG, again as in subjects with an intact corpus callosum. The data confirm that the skin regions adjacent to the trunk midline are represented bilaterally in SI, and indicate that ipsilateral activation is at least partially independent of the corpus callosum.

Latest generation of unipolar and bipolar steroid eluting leads: long-term comparison of electrical performance in atrium and ventricles.

One hundred and seventy-three patients, mean age 74 years permanently paced with 123 atrial (53 unipolar, 70 bipolar) and 143 ventricular (73 unipolar, 70 bipolar) pacing leads were included in this study. The pacing leads were recent generation low surface area steroid eluting leads from one manufacturer: leads with silicone and polyurethane insulation were studied, and they were combined with generations of one pacemaker family from the same manufacturer permitting identical measurements to be made over a follow-up of 2 years. Pacing threshold was measured using pulse duration at a fixed voltage of 1.5 V: peak to peak P and R wave amplitude and pacing impedance at 2.5 V and 0.5 ms were all measured using the manufacturer's standard programmer. Although many significant differences, in the parameters measures, existed between atrium and ventricle and unipolar and bipolar configurations, none was felt to be of clinical significance. These data permit the physician to choose the lead type with regard to sensing performance and long-term lead integrity.

Jugular vein thrombosis: a rare presentation of atypical chronic myeloproliferative disorder in a young woman.

Venous thromboembolism is common in subjects with chronic myeloproliferative disorders and is a recognized presenting feature of occult myeloproliferation. We report the case of a young woman who presented with acute thrombosis in the right jugular vein and pulmonary embolism. Splenomegaly and myeloid proliferation with bone marrow fibrosis, in the absence of the criteria for typical myeloproliferative disorders, allowed a diagnosis of an atypical form of chronic myeloproliferative disorder. This form carries a high risk of thrombosis and venous thromboembolism can be the presenting feature, though the course is often indolent. Acute thrombosis in the right jugular vein has not been so far described in these subjects. The outcome of young people with myelofibrosis is unpredictable, but a normal level of hemoglobin and the absence of blast cells and constitutional symptoms at presentation identifies subjects with a low probability of rapid disease progression.

Effects of long-term vasodilator therapy in patients with carotid sinus hypersensitivity.

BACKGROUND: In patients affected by carotid sinus hypersensitivity, long-term vasodilator therapy might increase the risk of syncopal episodes by reducing systolic blood pressure and venous return to the heart. METHODS AND RESULTS: Thirty-two patients (mean age 73 +/- 9 years; 20 men) who met all the following criteria were included: (1) one or more episodes of syncope occurring during long-term (>6 months) treatment with angiotensin-converting enzyme inhibitors, long-acting nitrates, calcium antagonists, or a combination of these; (2) a positive response to carotid sinus massage, defined as the reproduction of spontaneous syncope in the presence of ventricular asystole > or =3 seconds or a fall in systolic blood pressure > or =50 mm Hg; (3) negative workup for other causes of syncope. The patients were randomly assigned to continue or to discontinue use of vasodilators; carotid sinus massage was repeated 2 weeks after randomization. By the end of the study period, the baseline values of systolic blood pressure were significantly different between the 2 groups of patients both in supine (P=.01) and upright (P=.03) positions. Syncope had been induced by carotid sinus massage in 81% of patients in the "on-vasodilator" group and in 62% of patients in the "off-vasodilator" group (P=.21). The cardioinhibitory reflex was of similar magnitude in the 2 groups, being found in 50% of the patients in each group, with a maximum ventricular pause of 7.1 +/- 2.7 and 6.7 +/- 1.8 seconds, respectively. The percentage decrease of blood pressure did not differ between the 2 groups, even if, in absolute values, the baseline difference of blood pressure roughly persisted for the duration of the test. In consequence of that, the rise of blood pressure to similar values was delayed approximately 30 seconds in the "on-vasodilator" group and took more than 2 minutes to return to baseline values. CONCLUSIONS: In patients affected by carotid sinus hypersensitivity, chronic vasodilator therapy does not have a direct effect on carotid sinus reflexivity, although the delayed recovery of pretest blood pressure values could indirectly potentiate the severity of the clinical manifestations of the syndrome. The persistence of hypotension for a longer time after the end of the massage suggests that vasodilators cause an impairment of compensatory mechanisms.

Effects of chronic vasodilator therapy to enhance susceptibility to vasovagal syncope during upright tilt testing.

To evaluate the effect of chronic vasodilator therapy on susceptibility to vasovagal syncope, 45 patients with syncope and a positive response to tilt testing were randomly assigned to continue or to discontinue vasodilators. The study result demonstrated that chronic vasodilator therapy enhances susceptibility to vasovagal reaction during upright tilt testing.

[Diagnosis and follow-up of 330 patients admitted for syncope in the Department of Cardiology and Neurology. How important is an interdisciplinary study?]. / Diagnosi e follow-up di 330 pazienti ricoverati per sincope in Cardiologia e Neurologia. Quanto è importante uno studio interdisciplinare?

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.

Carotid sinus hypersensitivity and syndrome in patients with chronic atrial fibrillation.

Carotid sinus hypersensitivity (CSH) has been studied in subjects in sinus rhythm, but it has never been studied in patients with chronic atrial fibrillation (AF). After a finding of CSH in a patient with chronic AF and syncope, we studied the effects of carotid sinus stimulation in a group of patients with AF. Ten patients with chronic AF and normal ventricular rates who complained of dizziness or loss of consciousness underwent right and left carotid sinus massage (CSM) during ECG monitoring. A control group of ten patients with AF but without neurological symptoms was likewise investigated. CSH was present in eight symptomatic patients (5 patients presented right CSH, 1 left and 2 bilateral CSH), but only in three of the control patients. The mean duration of asystole induced by right CSM was 5.94 +/- 2.10 seconds; the mean asystolic interval induced by left CSM lasted 8.58 +/- 1.42 seconds. Six patients in the symptomatic group had a recurrence of spontaneous symptomatology during CSM, so that a diagnosis of carotid sinus syndrome was established. All symptomatic patients (8 patients with CSH, 2 patients with ventricular standstills but without CSH) received a permanent ventricular pacemaker. Following pacing, all patients, except for one with a significant drop of systolic blood pressure during CSM, became completely asymptomatic. In elder patients with chronic AF, CSH can induce prolonged ventricular asystole, which may be responsible for neurological symptoms such as dizziness, presyncope, or syncope, as observed in patients in sinus rhythm with carotid sinus syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Severe lumbar stenosis caused by chronic spinal epidural hematoma and multiple disk disease--case report and review of the literature.

We present a patient whose radicular syndrome resulted from combined compression by disk herniation and lumbar chronic spinal epidural hematoma (CSEH). The lesion was extensively studied by CT and MRI and the preoperative diagnosis confirmed by microscopic examination. CSEH is a rare entity, typical of elderly and invariably involving the lumbar canal: only 11 similar cases have been reported up to date. We propose that an undefined number of CSEH remains clinically silent, hidden in the roomy lumbar canal, displacing but not injuring the roots of the cauda. The routine use of Gd-DTPA MRI, even in emergency, will significantly decrease mistakes localization and will provide the correct differential diagnosis.

Parapharyngeal space lesions syncope-syndrome. A newly proposed reflexogenic cardiovascular syndrome.

An intense vaso-vagal reaction characterizes those reflex cardiovascular syncopes in which the glossopharyngeal nerve constitutes the main afferent nerve pathway. In these syndromes, afferent fibres of the glossopharyngeal nerve project from the baroreceptorial area to the medullary cardiac and vasomotor centres, from which efferent fibres descend into the vagus. The most common reflex cardiovascular syndromes linked to the IX nerve are carotid sinus syndrome (CSS) and glossopharyngeal neuralgia-asystole syndrome (GNS). Eleven male patients (mean age 65.4 years) with recurrent and severe vaso-vagal attacks are described. The episodes were characterized by asthenia and general malaise, pallor, sudation, unrecordable or very low (40-60 mmHg) arterial blood pressure, mental disorientation and/or syncope. The admission diagnosis in these patients was CSS, but the clinical picture was quite different from classic CSS: triggering factors were not present, vasovagal episodes were longer, syncopes were more frequent and severe and VVI pacing was ineffective. Further investigation, including computerized tomography, showed in all patients a malignant or benign pathological growth occupying and compressing the parapharyngeal space. The authors think that the symptoms exhibited by their patients may be attributed to parapharyngeal space involvement. The pathogenetic mechanism of syncope in these cases could be similar to that occurring in GNS except for the absence of neuralgia itself. Surgical carotid sinus denervation or A-V sequential DDD pacing were ineffective in completely controlling symptoms. Intracranial section of the IX nerve appears to be the most effective mechanism for controlling the syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hypersensitivity and carotid sinus syndrome in patients with chronic atrial fibrillation]. / Ipersensibilità e sindrome del seno carotideo in pazienti con fibrillazione atriale cronica.

BACKGROUND: Carotid sinus hypersensitivity (CSH) has always been described in patients in sinus rhythm; we did not find reports of CSH in patients with chronic atrial fibrillation (AF). After the observation of bilateral CSH in a patient with chronic AF admitted to our Division for syncope, we began to systematically study patients with chronic AF and neurological disturbances to evaluate carotid sinus stimulation effects upon cardiac activity and arterial blood pressure in these subjects. METHODS: We studied 28 subjects with chronic AF (mean age 73.3 yrs.; range 60-89): 16 patients had dizziness, fainting or syncope, and formed the study group (A); 12 asymptomatic patients were considered the control group (B). After a careful clinical and instrumental evaluation, all the patients underwent a 24 hour ambulatory (Holter) ECG analysis and right and left carotid sinus massage (CSM). If the latter manoeuvre induced asystolia longer than 3 seconds, CSM was repeated during ventricular pacing to evaluate the vasal component of the carotid sinus reflex. RESULTS: In group A, 24-hour Holter monitoring showed a greater incidence (81.2%) of ventricular standstill (mean duration 2.67 seconds) in comparison to the control group. In group A we found CSH in 75% of the cases, more frequently right CSH (7 subjects with right, 1 with left and 4 with bilateral CSH) with prolonged ventricular asystolia (mean duration 5.3 +/- 1.9 sec. with right CSM; 7.8 +/- 1.4 sec. with left CSM); during CSM, we reproduced spontaneous symptomatology in 9 patients. In 12 patients in group A, diagnosis of carotid sinus syndrome was established; the cardioinhibitory forms were clearly prevalent (91.7%); only one patient presented a cardioinhibitory-vasodepressor form with a predominant vasodepressor component. CONCLUSIONS: The authors believe that CSH is frequent in patients with chronic AF; the vagal hyperactivity due to CSH can induce prolonged ventricular asystole that may be responsible for neurological disturbances such as dizziness, fainting or syncope, as observed in patients in sinus rhythm with carotid sinus syndrome. Abnormal sensitivity of the carotid sinus could thus be one of the causes of increased morbidity and mortality in patients with chronic AF. The majority of these patients may be expected to benefit from permanent pacemaker therapy.

[Anomalous origin of the left coronary artery from the pulmonary artery. A rare case diagnosed in adulthood]. / Origine anomala della coronaria sinistra dall'arteria polmonare. Un raro caso diagnosticato in età adulta.

Anomalous origin of the left coronary artery from the pulmonary artery (Bland-White-Garland syndrome) is a rare but often lethal congenital lesion. Clinical manifestations of this syndrome present, in the large majority of cases, in infancy. The authors describe a case of Bland-White-Garland syndrome diagnosed in adult age.

[Hemodynamic and neuroendocrine profile of 2 different cardiovascular responses in vasodepressor syncope induced by the head-up tilt test]. / Profilo emodinamico e neuroendocrino di due distinte risposte cardiovascolari nella sincope vasodepressiva indotta da head-up tilt test.

BACKGROUND: Syncope in apparently healthy subjects is usually attributed to a vasovagal reaction. However, a vagal cardio-inhibitory component is not always associated with a vasodepressor component in causing syncope: in fact, increases in heart rate, arterial pressure and plasmatic levels of catecholamines frequently precede loss of consciousness. METHODS: Prolonged 60 degrees head-up tilt table test (HUTT) was performed in 50 healthy subjects (27 male, 23 female - mean age 37.2 years) with recurrent syncope of vasodepressor or unknown origin. The upright-tilt test lasted 45 minutes: every minute of HUTT we measured heart rate (HR) and systolic (SBP) and diastolic blood pressure (DBP); at set intervals we took a blood sample to determine epinephrine (EP) and norepinephrine (NEP) levels. RESULTS: In patients with positive HUTT (42%) we observed a vaso-vagal response (10 patients) characterized by a sharp drop in SBP and DBP (> 50% of the basal values) and bradycardia (< 40 bpm) and/or sinus node arrests, and a hyperchronotropic-vasodepressor response (11 patients) characterized by a considerable increase in HR (> 60%) and simultaneous drop in SBP and DBP (> 30% of the basal values), and a large increase in plasmal EP (+881.9%). CONCLUSIONS: According to the Authors, vasovagal response is mainly due to a reflex reaction originating from the cardiac stretch-receptors, whereas hyperchronotropic-vasodepressor response is mainly due to psychic stress and anxiety provoked by prolonged and forced posture during HUTT. The high levels of adrenergic activity and plasmal EP cause the excessive chronotropic response and the vasal effects of the syndrome. Due to the induction of a state of anxiety and its postural effects, HUTT is a useful provocative tool for complete evaluation of young patients with syncope of vasodepressor origin. We treated the patients differently, depending on how they responded to HUTT. Those with a vaso-vagal response were treated with alpha-sympathomimetic agents (ethylephrine or mydodrine) and those with a hyperchronotropic-vasodepressor response received non-selective beta-blockers. None of our patients had syncope recurrences during a mean follow-up of 12.3 months. Only two patients complained of dizziness; in one of them, symptomatology was abolished by an alpha-sympathomimetic beta-blocker association.

Effects of acute hypoxia on the normal and diseased sinus node.

We have studied the effects of breathing 12% oxygen in three groups of patients with sinus bradycardia: 11 with intrinsic sick sinus syndrome, 11 with extrinsic sick sinus syndrome and 11 without any evidence of sinus dysfunction. During hypoxia, the heart rate increased by an average of 6.7 beats/min in the patients with intrinsic sick sinus syndrome, 15.7 beats/min in the patients with extrinsic sick sinus syndrome and 14.3 beats/min in those with normal sinus node function. The difference in response of the heart rate between the two groups with sick sinus syndrome was highly significant (P less than 0.001). There was no difference between the three groups in the response of the blood pressure, ventilation, and partial pressures of oxygen and carbon dioxide. The increased heart rate which accompanies hypoxia is thought to be mediated through sympathetic mechanisms consequent on hyperventilation. In the intrinsic sick sinus syndrome, there is evidence that the sympathetic tone is already increased and this may limit the extent of the tachycardia due to hypoxia. Hypoxia may be a useful clinical test to distinguish between the two forms of sick sinus syndrome.

[Ventricular tachycardia induced by a bent catheter electrode migrated to the pulmonary artery]. / Tachicardia ventricolare indotta da catetere elettrodo incuneato "ad ansa" in arteria polmonare.

The possibility of migration of a transvenous electrode bend in the infundibulum of the pulmonary artery is a very rare complication of permanent pacing. The Authors describe the case of a patient whose transvenous electrode, positioned in the pulmonary artery 5 years after implantation, was presumably the cause of a ventricular hyperkinetic arrhythmia (VT) and of cerebral disturbances (sublipothymia, syncope). The re-position of the electrode removed the arrhythmia thus considerably improving the symptoms of the patient.

Duodenal stenosis from retroperitoneal fibrosis secondary to traumatic retroperitoneal hematoma: a case report.

A case is presented of retroperitoneal fibrosis secondary to post-traumatic retroperitoneal hematoma, resulting in duodenal obstruction six years after the traumatic event. The fibrotic encasement of the duodenum and the head of pancreas made it necessary to perform an "en bloc" resection, with excellent results both immediately and after three years of follow-up.