Massimo Del Sette

Migraine with Aura and Right-to-Left Shunt on Transcranial Doppler: A Case-Control Study

Right-to-left shunt (RLS), usually due to patent foramen ovale, is a well-established risk factor for ischemic stroke in young patients, while the role of migraine as an independent factor is still debated. We evaluated 44 patients suffering from migraine with aura, and compared them with 73 patients younger than 50 with focal cerebral ischemia, and 50 controls, asymptomatic for cerebrovascular disease, and without a history of migraine. All the subjects underwent bilateral transcranial Doppler with injection of contrast medium in an antecubital vein. The test was performed during normal ventilation and during Valsalva maneuver, recording both the middle cerebral arteries and the basilar artery. Criteria for diagnosing RLS was the presence of at least 3 microbubbles within 15 s from injection. Eighteen out of 44 migraine patients (41%) showed RLS, as opposed to 8 of 50 controls (16%) (p < 0.005). Twenty-six out of 73 patients with cerebral ischemia had RLS (35%). We conclude that the prevalence of RLS in patients with migraine with aura is significantly higher than in normal controls, and is similar to the prevalence of RLS in young patients with stroke. These findings could be helpful in understanding the relationship between migraine and stroke.

Serum Uric Acid and Target Organ Damage in Primary Hypertension

The role of serum uric acid as an independent risk factor for cardiovascular and renal morbidity is controversial. A better understanding of its relationship with preclinical organ damage may help clarify the mechanism(s) implicated in the development of early cardiovascular disease. We evaluated the association between uric acid and the presence and degree of target organ damage in 425 (265 males, 160 females) middle-aged, untreated patients with essential hypertension. Left ventricular mass index and carotid intima-media thickness were assessed by ultrasound scan. Albuminuria was measured as the albumin to creatinine ratio in 3 nonconsecutive first morning urine samples. Overall, patients with target organ damage had significantly higher levels of serum uric acid as compared with those without it (presence versus absence of left ventricular hypertrophy, P=0.04; carotid abnormalities, P<0.05; microalbuminuria, P<0.004; and at least 1 versus no organ damage, P<0.03). In women, the occurrence and severity of each target organ damage we examined increased progressively from the lower to the upper serum uric acid tertiles (P<0.01). After adjustment for body mass index, age, creatinine clearance, and high-density lipoprotein cholesterol, each standard deviation increase in serum uric acid entailed a 75% higher risk of having cardiac hypertrophy and a 2-times greater risk of having carotid abnormalities. These results support the role of serum uric acid as an independent, modifiable marker of cardiovascular damage.

Grading Carotid Stenosis Using Ultrasonic Methods

The controversy as to whether Doppler ultrasonic methods should play a role in clinical decision-making in the prevention of stroke is attributable to reported disagreement between angiographic and ultrasonic results and the lack of internationally accepted ultrasound criteria for describing the degree of stenosis. Foremost among the explanations for both is the broad scatter of peak systolic velocities in the stenosis, the criterion that has so far received most attention. Grading based on a set of main and additional criteria can overcome diagnostic errors. Morphological measurements (B-mode images and color flow imaging) are the main criteria for low and moderate degrees of stenosis. Increased velocities in the stenosis indicate narrowing, but the appearance of collateral flow and decreased poststenotic flow velocity prove a high degree stenosis (≥70%), additionally allowing the estimation of the hemodynamic effect in the category of high-degree stenosis. Additional criteria refer to the effect of a stenosis on prestenotic flow (common carotid artery), the extent of poststenotic flow disturbances, and derived velocity criteria (diastolic peak velocity and the carotid ratio). This multiparametric approach is intended to increase the reliability and the standard of reporting of ultrasonic results for arteriosclerotic disease of the carotid artery.

Microalbuminuria Is an Early Marker of Target Organ Damage in Essential Hypertension

Microalbuminuria has been associated with a cluster of metabolic and nonmetabolic risk factors, suggesting that it might indicate the presence of generalized microvascular damage in patients with essential hypertension. To explore whether microalbuminuria is associated with early target organ damage, two groups of essential hypertensive patients, with (n = 17) (HtAlb+) and without (n = 16) (HtAlb-) microalbuminuria, and a control group (C) of healthy normotensive subjects (n = 20) were studied. The study groups, selected among participants of a large epidemiologic trial, were carefully matched for several potentially confounding variables such as gender, age, duration of hypertension, and body mass index. Albumin excretion rate was evaluated by radioimmunoassay in three nonconsecutive timed overnight collections after 3 weeks of pharmacologic wash-out. Left ventricular mass was assessed by M-B-mode echocardiography, carotid wall thickness by a high resolution ultrasound scan, and renal vascular impedance by Doppler scan. Office as well as 24-h ambulatory pressure monitoring (Takeda TM-2420) were also evaluated. There was no difference between the two hypertensive groups for office and 24-h blood pressure levels except for a lower daytime/nighttime systolic blood pressure ratio in the group with microalbuminuria. Microalbuminuric patients showed signs of early organ damage as compared to normoalbuminuric patients and normal subjects, namely greater left ventricular mass indices (LVMI 167+/-7 g/m2 in HtAlb+; 139+/-9 g/m2 in HtAlb-; 118+/-5 g/m2 in C, P < .001) and increased wall thickness of common carotid arteries (intima plus media thickness 12.5+/-0.2 mm in HtAlb+; 11.7+/-0.3 mm in HtAlb-; 11.2+/-0.2 mm in C, P < .001) as well as higher intrarenal vascular resistance (mean resistive index 0.62+/-0.01 in HtAlb+; 0.59+/-0.01 in HtAlb-; 0.59+/-0.01 in C, P < .05). In conclusion, microalbuminuria is an early marker of diffuse target organ damage in essential hypertension and therefore can be useful to identify patients for whom more aggressive preventive strategies or additional treatment measures are advisable.

Prevalence of patent foramen ovale in subjects with obstructive sleep apnea: a transcranial Doppler ultrasound study

BACKGROUND Under particular conditions a patent foramen ovale (PFO) can potentially give rise to ischemic stroke by means of paradoxic embolization. In obstructive sleep apnea syndrome (OSAS) right to left shunting (RLSh) can occur through PFO during periods of nocturnal apnea. Our study aimed to evaluate the prevalence of PFO diagnosed by means of transcranial Doppler (TcD) in subjects with OSAS. METHODS Seventy-eight consecutive subjects with OSAS (mean age 53+/-12 years) and 89 normal controls (mean age 48+/-9 years) underwent TcD with intravenous application of agitated physiological saline solution. The test was performed on patients at rest and during Valsalva maneuver. RESULTS PFO was present in 21 out of 78 patients with OSA (27%) and in 13 out of 89 control patients (15%). Seventeen out of 21 patients with OSA showed PFO only during Valsalva maneuver (85%) with respect to 12 out of 13 subjects of the control group (92%). Prevalence of PFO in OSAS was statistically different with respect to the control group (P<0.05). However, no statistically significant differences could be found for the prevalence of provocative-only shunting PFO with respect to already at rest shunting PFO in patients with OSAS with respect to the control group. CONCLUSIONS Prevalence of PFO in subjects with OSA is significantly higher than in normal controls. The shunt is frequently present only during Valsalva maneuver.

Mild Renal Dysfunction and Subclinical Cardiovascular Damage in Primary Hypertension

Abstract—The presence of mild renal dysfunction is associated with high cardiovascular morbidity and mortality rates in patients with primary hypertension. The pathophysiological mechanisms underlying this association are currently unknown. We investigated the relation between mild renal dysfunction and subclinical cardiovascular organ damage in 358 never previously treated patients with primary hypertension. Mild renal dysfunction was defined as a creatinine clearance <60 mL/min and/or the presence of microalbuminuria. Left ventricular mass index and carotid intima-media thickness were assessed by ultrasound scan. The prevalence of mild renal dysfunction, left ventricular hypertrophy, and carotid plaque was 18%, 48%, and 28%, respectively. Mild renal dysfunction was related to the presence of several risk factors, such as older age, higher blood pressure levels and lipid status, and smoking habits. Patients with the highest left ventricular mass and carotid intima-media thickness (upper quartiles) showed a higher prevalence of mild renal dysfunction (P <0.0001). After adjusting for duration of hypertension, mean blood pressure, smoking habits, and age, we found that the risk of left ventricular hypertrophy and/or carotid atherosclerosis increased by 43% with each SD reduction in creatinine clearance, and by 89% with each SD increase in albuminuria. Mild renal dysfunction is associated with preclinical end-organ damage in patients with primary hypertension. These data may help explain the high cardiovascular mortality rates reported in patients with low glomerular filtration rate or with increased albuminuria. The evaluation of creatinine clearance and urinary albumin excretion could be useful for identifying subjects at higher cardiovascular risk.

Systemic thrombolysis in patients with acute ischemic stroke and Internal Carotid ARtery Occlusion: the ICARO study

Background and Purpose— The beneficial effect of intravenous thrombolytic therapy in patients with acute ischemic stroke attributable to internal carotid artery (ICA) occlusion remains unclear. The aim of this study was to evaluate the efficacy and safety of intravenous recombinant tissue-type plasminogen activator in these patients. Methods— ICARO was a case-control multicenter study on prospectively collected data. Patients with acute ischemic stroke and ICA occlusion treated with intravenous recombinant tissue-type plasminogen activator within 4.5 hours from symptom onset (cases) were compared to matched patients with acute stroke and ICA occlusion not treated with recombinant tissue-type plasminogen activator (controls). Cases and controls were matched for age, gender, and stroke severity. The efficacy outcome was disability at 90 days assessed by the modified Rankin Scale, dichotomized as favorable (score of 0–2) or unfavorable (score of 3–6). Safety outcomes were death and any intracranial bleeding. Results— Included in the analysis were 253 cases and 253 controls. Seventy-three cases (28.9%) had a favorable outcome as compared with 52 controls (20.6%; adjusted odds ratio (OR), 1.80; 95% confidence interval [CI], 1.03–3.15; P=0.037). A total of 104 patients died, 65 cases (25.7%) and 39 controls (15.4%; adjusted OR, 2.28; 95% CI, 1.36–3.22; P=0.001). There were more fatal bleedings (2.8% versus 0.4%; OR, 7.17; 95% CI, 0.87–58.71; P=0.068) in the cases than in the controls. Conclusions— In patients with stroke attributable to ICA occlusion, thrombolytic therapy results in a significant reduction in the proportion of patients dependent in activities of daily living. Increases in death and any intracranial bleeding were the trade-offs for this clinical benefit.

Risk factors in lacunar syndromes: a case‐control study

ABSTRACT— The association between some hypothetical risk factors (previous TIA, hypertension, ECG ischemic abnormalities, diabetes, cigarette smoking, atrial fibrillation, hypercholesterolemia, hypertriglyceridemia, high hematocrit) and lacunar syndromes has been evaluated by a matched sample case‐control study involving 108 consecutive, incident cases with lacunar syndrome and 216 hospital control subjects, matched for sex and age. A significant increase of Relative Risk (RR) has been shown for: 1. Previous history of TIA; 2. Hypertension; 3. Smoking; 4. Diabetes. No relevance was shown for: 1. Atrial fibrillation; 2. Hypercholesterolemia; 3. Hypertriglyceridemia; 4. High hematocrit. The analysis of the triplets of subjects (1 case + 2 controls) without hypertension showed a significant RR increase for: 1. Previous history of TIA; 2. Ischemic cardiac abnormalities; 3. Atrial fibrillation. Such findings support the hypothesis that, in a minority of cases with lacunar syndrome, the pathogenetic mechanism could be different from occlusion of penetrating arteries in hypertensive patients.

Early Recurrence and Cerebral Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Effect of Anticoagulation and Its Timing: The RAF Study

Background and Purpose— The best time for administering anticoagulation therapy in acute cardioembolic stroke remains unclear. This prospective cohort study of patients with acute stroke and atrial fibrillation, evaluated (1) the risk of recurrent ischemic event and severe bleeding; (2) the risk factors for recurrence and bleeding; and (3) the risks of recurrence and bleeding associated with anticoagulant therapy and its starting time after the acute stroke. Methods— The primary outcome of this multicenter study was the composite of stroke, transient ischemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding and major extracranial bleeding within 90 days from acute stroke. Results— Of the 1029 patients enrolled, 123 had 128 events (12.6%): 77 (7.6%) ischemic stroke or transient ischemic attack or systemic embolism, 37 (3.6%) symptomatic cerebral bleeding, and 14 (1.4%) major extracranial bleeding. At 90 days, 50% of the patients were either deceased or disabled (modified Rankin score ≥3), and 10.9% were deceased. High CHA2DS2-VASc score, high National Institutes of Health Stroke Scale, large ischemic lesion and type of anticoagulant were predictive factors for primary study outcome. At adjusted Cox regression analysis, initiating anticoagulants 4 to 14 days from stroke onset was associated with a significant reduction in primary study outcome, compared with initiating treatment before 4 or after 14 days: hazard ratio 0.53 (95% confidence interval 0.30–0.93). About 7% of the patients treated with oral anticoagulants alone had an outcome event compared with 16.8% and 12.3% of the patients treated with low molecular weight heparins alone or followed by oral anticoagulants, respectively (P=0.003). Conclusions— Acute stroke in atrial fibrillation patients is associated with high rates of ischemic recurrence and major bleeding at 90 days. This study has observed that high CHA2DS2-VASc score, high National Institutes of Health Stroke Scale, large ischemic lesions, and type of anticoagulant administered each independently led to a greater risk of recurrence and bleedings. Also, data showed that the best time for initiating anticoagulation treatment for secondary stroke prevention is 4 to 14 days from stroke onset. Moreover, patients treated with oral anticoagulants alone had better outcomes compared with patients treated with low molecular weight heparins alone or before oral anticoagulants.

Microembolic Signals With Serial Transcranial Doppler Monitoring in Acute Focal Ischemic Deficit A Local Phenomenon

BACKGROUND AND PURPOSE The occurrence of microembolic signals (MES) in patients with transient ischemic attack (TIA) or stroke has already been described, but the diagnostic and prognostic value of this finding is still debated. METHODS We evaluated 90 consecutive patients admitted for their first hemispheric TIA or ischemic stroke within 72 hours of onset. All of them underwent 30-minute bilateral transcranial Doppler monitoring of middle cerebral arteries, within 72 hours of onset. The monitoring was repeated after an additional 24 hours and after 7 days. We then classified the episodes in the following etiologic categories: cardioembolic, atherothrombotic, small-vessel disease, mixed cases, unknown origin, and other causes. RESULTS We included 75 patients, with a mean interval of registration of 32.04 +/- 19.39 hours. There were 9 patients with MES (12%). All MES were recorded only on the symptomatic middle cerebral artery, and the majority were recorded during the first or the second registration. No statistically significant difference was found in risk factors and hematologic parameters. Five patients (56%) had atherothrombotic episodes, 3 patients (33%) had cardioembolic episodes, and 1 patient (11%) had a protein S deficit. No patient with MES had small-vessel disease (P = .01). CONCLUSIONS MES are an infrequent finding in patients with TIA or ischemic stroke within 72 hours of onset, but they can be recorded more easily with serial registration. In our patients, MES were found only on the symptomatic middle cerebral artery and were present in atherothrombotic and cardioembolic episodes but not in small-vessel disease.