Rossana Tassi

Autonomic activity and baroreflex sensitivity in patients submitted to carotid stenting

Arterial baroreflex and cardiac autonomic control play important roles in hemodynamic instability after carotid artery stenting (CAS). Spontaneous baroreflex sensitivity (BRS), heart rate variability (HRV) and blood pressure variability (BPV) are established tools for the assessment of arterial baroreflex and cardiac autonomic activity. Aim of the study was to evaluate cardiac autonomic activity (by means of HRV, BPV and BRS) after CAS and to explore the impact of internal carotid artery stenosis on BRS changes after CAS. 37 patients (68±10.45 years) with internal carotid stenosis underwent CAS. HRV, BPV and BRS were measured in all subjects before and at 1 and 72h after CAS. ANOVA was performed to compare BRS, HRV and BPV parameters before and after CAS. Spearman analysis was performed to determine a possible correlation between carotid stenosis degree (or carotid plaque diameter) and BRS changes (ΔBRS). LF/HF (index of sympatho-vagal balance) decreased during postoperative period, in comparison with baseline (2.32±1.70 vs 1.65±1.40, p<0.05). There was a significant negative correlation between carotid stenosis degree and ΔBRS (r=-0.35, p=0.03) and between carotid plaques thickness and ΔBRS (r=-0.36, p=0.02). CAS procedure may cause an alteration of carotid wall mechanical properties, increasing baroreflex sensitivity. BRS does not increase in all the patients, because arterial wall damage and nerve destruction determined by atherosclerotic plaque may reduce ΔBRS.

Ischemic Stroke after Heart Transplantation

Cerebrovascular complications after orthotopic heart transplantation (OHT) are more common in comparison with neurological sequelae subsequent to routine cardiac surgery. Ischemic stroke and transient ischemic attack (TIA) are more common (with an incidence of up to 13%) than intracranial hemorrhage (2.5%). Clinically, ischemic stroke is manifested by the appearance of focal neurologic deficits, although sometimes a stroke may be silent or manifests itself by the appearance of encephalopathy, reflecting a diffuse brain disorder. Ischemic stroke subtypes distribution in perioperative and postoperative period after OHT is very different from classical distribution, with different pathogenic mechanisms. Infact, ischemic stroke may be caused by less common and unusual mechanisms, linked to surgical procedures and to postoperative inflammation, peculiar to this group of patients. However, many strokes (40%) occur without a well-defined etiology (cryptogenic strokes). A silent atrial fibrillation (AF) may play a role in pathogenesis of these strokes and P wave dispersion may represent a predictor of AF. In OHT patients, P wave dispersion correlates with homocysteine plasma levels and hyperhomocysteinemia could play a role in the pathogenesis of these strokes with multiple mechanisms increasing the risk of AF. In conclusion, stroke after heart transplantation represents a complication with considerable impact not only on mortality but also on subsequent poor functional outcome.

Safety of Intravenous Thrombolysis in Ischemic Stroke Caused by Left Atrial Myxoma

Intravenous thrombolytic treatment represents the gold standard for acute ischemic stroke treatment. However there is some concern to perform this treatment in patients with known cardiac myxomas for the risk of haemorragic complications. Here we described a 63-year-old patient with ischemic stroke due to embolization of atrial myxoma and treated with intravenous recombinant tissue plasminogen activator alteplase. The patient did not show improvement after treatment; 25 days later a brain CT showed an asymptomatic small hemorrhagic infarction, probably due to the large size of ischemic lesion. The lack of response might be explained by the embolization of a large tumor fragment. One-year after cardiac surgery clinical follow-up did not reveal new neurological signs nor symptoms. This case report suggests that systemic thrombolysis is a safe procedure also in patient with atrial myxoma. The efficacy of therapy seems to be related to embolus composition.

Relationship between the modified Rankin Scale and the Barthel Index in the process of functional recovery after stroke.

OBJECTIVEnThe modified Rankin Scale (mRS) and the Barthel Index (BI) are the most common clinimetrical instruments for measuring disability after stroke. This study investigated the relationship between the BI and the mRS at multiple time points after stroke. The BI, which is a widely used instrument for longitudinal follow-up post-stroke, was used as reference to determine the effect of time on the sensitivity of the mRS in differentiating functional recovery.nnnMETHODSnNinety-two patients with first stroke and hemispheric brain lesion were evaluated using the BI and mRS at 10 days, 3 and 6 months. The Kruskal-Wallis test was applied to examine median differences in BI among the mRS levels at 10 days, 3 and 6 months with Dunns correction for multigroup comparison. The Mann and Whitney test was used to compare median differences in BI scores between two aggregations of mRS grades (mRS=0-2, mRS=3-5) at the same time periods after stroke.nnnRESULTSnBI score distribution amongst mRS grades overlapped at 10 days, differentiating only between extreme grades (no disability vs severe disability). At 3 months, independent patients with slight disability could be distinguished from dependent patients with marked disability. At 6 months, grade 2 and 3 overlapped no more, differentiating independence (class 0-2) from dependence (class 3-5). The largest transition to an independent functional status occurred from grade 4, at 3 months.nnnCONCLUSIONnMaximum sensitivity of mRS in differentiating functional recovery is reached at six months post-stroke.

Arterial Stiffness in Patients with Deep and Lobar Intracerebral Hemorrhage

Background and Purpose Intracerebral hemorrhage (ICH) accounts for approximately 10% of stroke cases. Hypertension may play a role in the pathogenesis of ICH that occurs in the basal ganglia, thalamus, pons, and cerebellum, but not in that of lobar ICH. Hypertension contributes to decreased elasticity of arteries, thereby increasing the likelihood of rupture in response to acute elevation in intravascular pressure. This study aimed to evaluate arterial stiffness (using the arterial stiffness index [ASI]) in patients with deep (putaminal and thalamic) ICH in comparison with patients with lobar ICH. Methods We enrolled 64 patients (mean±SD age: 69.3±10.7 years; 47 men and 17 women) among 73 who referred consecutively to our department for intraparenchymal hemorrhage and underwent brain computed tomography (CT) and cerebral angio-CT. In all the subjects, 24-hour heart rates and blood pressures were monitored. The linear regression slope of diastolic on systolic blood pressure was assumed as a global measure of arterial compliance, and its complement (1 minus the slope), ASI, has been considered as a measure of arterial stiffness. Results In the patients with deep ICH, ASI was significantly higher than in the patients with lobar ICH (0.64±0.19 vs. 0.53±0.17, P=0.04). Conclusions Our results suggest that in deep ICH, arterial stiffening represents a possible pathogenetic factor that modifies arterial wall properties and contributes to vascular rupture in response to intravascular pressure acute elevation. Therapeutic strategies that reduce arterial stiffness may potentially lower the incidence of deep hemorrhagic stroke.

Thrombolytic Treatment of Cardiac Myxoma-Induced Ischemic Stroke: A Review

Primary cardiac tumors are uncommon, with an autopsy frequency of 0.001%-0.28%: 75% of them are benign, and 50-75% of these are myxomas. Often the first neurological manifestations of a cardiac myxoma include transient ischemic attacks and ischemic strokes. Although thrombolytic therapy represents the gold standard for acute ischemic stroke treatment, its safety and effectiveness in stroke patients with myxoma is unknown. From the analysis of the literature on thrombolysis in ischemic stroke patients with myxoma we report clinical evidence supporting the use of thrombolytics, and the application of thrombolysis in this setting of patients. 23 previous reports presented patients with acute ischemic stroke and associated cardiac myxoma treated with thrombolytic therapy: 16 patients were treated with intravenous thrombolysis, 4 patients with intra-arterial thrombolysis and 3 patients were treated with bridging therapy (intravenous alteplase followed by local mechanical thrombolysis). Our review showed that the possible risk of major bleeding in these patients resulted in limited and small hemorrhages; furthermore patients who developed cerebral hemorrhage did not deteriorate clinically: waiting for further confirmation and additional data from a future register, these observations may suggest that, notwithstanding a possible publication bias, i.v. thrombolytic therapy may be a safe treatment in these patients.

Stroke warning syndrome: 18 new cases

BACKGROUNDnStroke warning syndrome (SWS) is a rare cause of stroke characterized by recurrent and short-lasting episodes of transient focal neurological deficits leading up to infarction. On the basis of clinical findings and neuroimaging, it can be capsular, pontine, or callosal. The aim of this study is to evaluate the prevalence of SWS in patients admitted to our Stroke Unit for an ischemic stroke and to look for the difference in outcome between patients treated or not with systemic thrombolysis by intravenous recombinant tissue plasminogen activator (IV-rtPA).nnnMETHODSnAmong the 967 patients admitted to our Stroke Unit between April 2008 and January 2013 for ischemic stroke, we identified 18 patients with SWS. Nine patients underwent IV-rtPA (IV Group) and the other 9 (No IV Group) other therapies.nnnRESULTSnThe prevalence of SWS in our population was 1.8%. The most common risk factors were hypertension and dyslipidemia in both groups. A good outcome at 3-month follow-up (modified Rankin Scale 0-2) was found in 3 patients (33%) in IV Group and in 5 patients (55%) in No IV Group.nnnCONCLUSIONnSWS is an under-recognized syndrome. Intravenous rt-PA treatment seems to have lower efficacy than in other subtypes of strokes, but none of the patients with SWS undergoing treatment presented haemorrhagic transformation or other complications.

Increased arterial stiffness is an independent risk factor for hemorrhagic transformation in ischemic stroke undergoing thrombolysis

BACKGROUNDnHemorrhagic transformation (HT) is a multifactorial phenomenon and represents a possible complication of ischemic stroke, especially after thrombolytic treatment. Increased arterial stiffness has been associated with intracranial hemorrhage, but there is no evidence of association with HT after thrombolytic therapy. The aim of our study is to investigate a possible link between arterial stiffness and HT occurrence after thrombolytic therapy in patients with ischemic stroke.nnnMETHODSnWe enrolled 258 patients (135 males, 123 females; mean age: 73±12years) with acute ischemic stroke undergoing intravenous thrombolysis or/and mechanical thrombectomy. All stroke patients underwent neuroimaging examination, 24-h heart rate and blood pressure monitoring and brain CT-scan after 24-72h to evaluate HT occurrence. The linear regression slope of diastolic on systolic blood pressure was obtained and assumed as a global measure of arterial compliance, and its complement (1 minus the slope), named arterial stiffness index (ASI), has been taken as a measure of arterial stiffness.nnnRESULTSnOut of 258, HT occurred in 55 patients. ASI was significantly higher in patients with HT than in patients without HT (0.70±0.12 vs 0.62±0.14, p<0.001). Logistic regression model showed ASI as independent predictors of HT (OR: 1.9, 95% CI: 1.09-3.02, for every 0.2 increase of ASI): in particular, OR was 5.2 (CI: 2.22-12.24) when ASI was >0.71, in comparison with ASI lower than 0.57.nnnCONCLUSIONSnOur results point to arterial stiffness as a novel independent risk factor for HT after ischemic stroke treated with thrombolysis, suggesting a particularly high bleeding risk when ASI is >0.71.

Predictors of long-term recovery in complex activities of daily living before discharge from the stroke unit.

BACKGROUND AND PURPOSEnThere is a need for individuating those post-stroke patients who may benefit from an optimal and customised rehabilitation plan aiming at early reintegration in community life participation. This study investigated whether the gain of independence in complex Activities of Daily Living (ADL) may be predicted before the discharge from the stroke unit using simple bedside determinants.nnnMETHODSnIn 104 first-ever stroke patients with no previous disability, ten determinants at 10 days after stroke were selected. Multivariable logistic regression analysis was applied to identify the prognostic determinants able to predict independence in complex ADL, as measured by modified Rankin Scale grade ≤2.nnnRESULTSnThe model shows that having a Barthel Index ≥9, a Motricity Index- Upper Limb ≥75, an age ≤70 and being a male resulted in 100% probability of achieving independence in complex ADL. If three of the four determinants were present, the probability was more than 90%. With the presence of two of the four determinants, the probability ranged from 87% to 28%. With the presence of only one determinant, the probability was 13%.nnnCONCLUSIONSnAccurate prediction of independence in complex ADL can be made before the discharge from the stroke unit. The strength of the paretic upper limb, age, gender, and the ability of performing basic ADL are the significant variables. The probability of favorable prognosis depends on the presence and on the robustness of each single determinant.

Double ophthalmic arteries arising from the internal carotid artery: a case report of a hidden second ophthalmic artery

A case of double ophthalmic arteries arising from the internal carotid artery with unique features is reported. This case was discovered following in the course of time the progress of a thrombosis of the anterior cavernous sinus associated with a low-flow direct arteriovenous fistula of the superior ophthalmic vein. At different time points, the same patient underwent four angiographic studies and one computerized tomography with contrast medium. Angiographies showed that the double internal carotid artery origin of the ophthalmic artery was detectable only within a short range of time. To the best of our knowledge, this case is unique as it demonstrates that a second ophthalmic artery may lie hidden, showing itself only under particular hemodynamic requirements.