Krassen Nedeltchev

Percutaneous closure of patent foramen ovale reduces the frequency of migraine attacks

Among 215 patients referred for percutaneous closure of patent foramen ovale (PFO) after presumed paradoxical embolism, we assessed the prevalence of migraine. In the year prior to PFO closure, 48 (22%) patients had migraine, twice the expected prevalence of 10 to 12% in the general European population. In patients with migraine with aura, percutaneous PFO closure reduced the frequency of migraine attacks by 54% (1.2 ± 0.8 vs 0.6 ± 0.8 per month; p = 0.001) and in patients with migraine without aura by 62% (1.2 ± 0.7 vs 0.4 ± 0.4 per month; p = 0.006). PFO closure did not have an effect on headache frequency in patients with nonmigraine headaches (1.4 ± 0.9 vs 1.0 ± 0.9 per month; p = NS).

NIHSS Score and Arteriographic Findings in Acute Ischemic Stroke

Background and Purpose— To test the hypothesis that the National Institutes of Health Stroke Scale (NIHSS) score is associated with the findings of arteriography performed within the first hours after ischemic stroke. Methods— We analyzed NIHSS scores on hospital admission and clinical and arteriographic findings of 226 consecutive patients (94 women, 132 men; mean age 62±12 years) who underwent arteriography within 6 hours of symptom onset in carotid stroke and within 12 hours in vertebrobasilar stroke. Results— From stroke onset to hospital admission, 155±97 minutes elapsed, and from stroke onset to arteriography 245±100 minutes elapsed. Median NIHSS was 14 (range 3 to 38), and scores differed depending on the arteriographic findings (P<0.001). NIHSS scores in basilar, internal carotid, and middle cerebral artery M1 and M2 segment occlusions (central occlusions) were higher than in more peripherally located, nonvisible, or absent occlusions. Patients with NIHSS scores ≥10 had positive predictive values (PPVs) to show arterial occlusions in 97% of carotid and 96% of vertebrobasilar strokes. With an NIHSS score of ≥12, PPV to find a central occlusion was 91%. In a multivariate analysis, NIHSS subitems such as “level of consciousness questions,” “gaze,” “motor leg,” and “neglect” were predictors of central occlusions. Conclusions— There is a significant association of NIHSS scores and the presence and location of a vessel occlusion. With an NIHSS score ≥10, a vessel occlusion will likely be seen on arteriography, and with a score ≥12, its location will probably be central.

Intra-Arterial Thrombolysis in 100 Patients With Acute Stroke Due to Middle Cerebral Artery Occlusion

Background and Purpose— The purpose of this study was to evaluate the safety and efficacy of local intra-arterial thrombolysis (LIT) using urokinase in patients with acute stroke due to middle cerebral artery (MCA) occlusion. Methods— We analyzed clinical and radiological findings and functional outcome 3 months after LIT with urokinase of 100 consecutive patients. To measure outcome, the modified Rankin scale (mRs) score was used. Results— Angiography showed occlusion of the M1 segment of the MCA in 57 patients, of the M2 segment in 21, and of the M3 or M4 segment in 22. The median National Institutes of Health Stroke Scale (NIHSS) score at admission was 14, and, on average, 236 minutes elapsed from symptom onset to LIT. Forty-seven patients (47%) had an excellent outcome (mRs score 0 to 1), 21 (21%) a good outcome (mRs score 2), and 22 (22%) a poor outcome (mRs score 3 to 5). Ten patients (10%) died. Excellent or good outcome (mRs score ≤2) was seen in 59% of patients with M1 or M2 and 95% of those with M3 or M4 MCA occlusions. Recanalization as seen on angiography was complete (thrombolysis in myocardial infarction [TIMI] grade 3) in 20% of patients and partial (TIMI grade 2) in 56% of patients. Age <60 years (P <0.05), low NIHSS score at admission (P <0.00001), and vessel recanalization (P =0.0004) were independently associated with excellent or good outcome and diabetes with poor outcome (P =0.002). Symptomatic cerebral hemorrhage occurred in 7 patients (7%). Conclusions— LIT with urokinase that is administered by a single organized stroke team is safe and can be as efficacious as thrombolysis has been in large multicenter clinical trials.

Clinical and radiological predictors of recanalisation and outcome of 40 patients with acute basilar artery occlusion treated with intra-arterial thrombolysis

Objective: To define predictors of recanalisation and clinical outcome of patients with acute basilar artery occlusions treated with local intra-arterial thrombolysis (IAT). Methods: Vascular risk factors, severity of the neurological deficit graded by the National Institutes of Health stroke scale (NIHSS), and radiological findings were recorded at presentation. Outcome was measured using the modified Rankin scale (mRS) three months later and categorised as favourable (mRS 0–2), poor (mRS 3–5), or death (mRS 6). Results: 40 patients were studied. Median NIHSS on admission was 18. Mean time from symptom onset to treatment was 5.5 hours (range 2.3 to 11). Outcome was favourable in 14 patients (35%) and poor in nine (23%); 17 (42%) died. There were two symptomatic cerebral haemorrhages (5%). Recanalisation of the basilar artery was achieved in 32 patients (80%); it was complete (TIMI grade 3) in 20% and partial (TIMI grade 2) in 60%. In multivariate logistic regression analysis, low NIHSS score on admission (p = 0.002) and vessel recanalisation (p = 0.005) were independent predictors of favourable outcome. Recanalisation occurred more often with treatment within six hours of symptom onset (p = 0.003) and when admission computed tomography showed a hyperdense basilar artery sign (p = 0.007). In a univariate model, quadriplegia (p = 0.002) and coma (p = 0.004) were associated with a poor outcome or death. Conclusions: Low baseline NIHSS on admission and recanalisation of basilar artery occlusions predict a favourable outcome after intra-arterial thrombolysis. Early initiation of IAT and the presence of a hyperdense basilar artery sign on CT were associated with a higher likelihood of recanalisation.

Comparison of Intraarterial and Intravenous Thrombolysis for Ischemic Stroke With Hyperdense Middle Cerebral Artery Sign

Background and Purpose— It is unclear whether intraarterial (IAT) or intravenous (IVT) thrombolysis is more effective for ischemic stroke with hyperdense middle cerebral artery sign (HMCAS) on computed tomography (CT). The aim of this study was to compare IAT and IVT in stroke patients with HMCAS. Methods— Comparison of data from 2 stroke units with similar management of stroke associated with HMCAS, except that 1 unit performed IAT with urokinase and the other IVT with plasminogen activator. Time to treatment was up to 6 hours for IAT and up to 3 hours for IVT. Outcome was measured by mortality and the modified Rankin Scale (mRS), dichotomized at 3 months into favorable (mRS 0 to 2) and unfavorable (mRS 3 to 6). Results— One hundred twelve patients exhibited a HMCAS, 55 of 268 patients treated with IAT and 57 of 249 patients who underwent IVT. Stroke severity at baseline and patient age were similar in both groups. Mean time to treatment was longer in the IAT group (244±63 minutes) than in the IVT group (156±21 minutes; P=0.0001). However, favorable outcome was more frequent after IAT (n=29, 53%) than after IVT (n=13, 23%; P=0.001), and mortality was lower after IAT (n=4, 7%) than after IVT (n=13, 23%; P=0.022). After multiple regression analysis IAT was associated with a more favorable outcome than IVT (P=0.003) but similar mortality (P=0.192). Conclusion— In this observational study intraarterial thrombolysis was more beneficial than IVT in the specific group of stroke patients presenting with HMCAS on CT, even though IAT was started later. Our results indicate that a randomized trial comparing both thrombolytic treatments in patients with middle cerebral artery occlusion is warranted.

Prevalence and size of directly detected patent foramen ovale in migraine with aura

Background: Transcranial contrast Doppler studies have shown an increased prevalence of right-to-left shunts in patients with migraine with aura compared with controls. The anatomy and size of these right-to-left shunts have never been directly assessed. Methods: In a cross-sectional case-control study, the authors performed transesophageal contrast echocardiography in 93 consecutive patients with migraine with aura and 93 healthy controls. Results: A patent foramen ovale was present in 44 (47% [95% CI 37 to 58%]) patients with migraine with aura and 16 (17% [95% CI 10 to 26%]) control subjects (OR 4.56 [95% CI 1.97 to 10.57]; p < 0.001). A small shunt was equally prevalent in migraineurs (10% [95% CI 5 to 18%]) and controls (10% [95% CI 5 to 18%]), but a moderate-sized or large shunt was found more often in the migraine group (38% [95% CI 28 to 48%] vs 8% [95% CI 2 to 13%] in controls; p < 0.001). The presence of more than a small shunt increased the odds of having migraine with aura 7.78-fold (95% CI 2.53 to 29.30; p < 0.001). Besides patent foramen ovale prevalence and shunt size, no other echocardiographic differences were found between the study groups. Headache and baseline characteristics did not differ in migraine patients with and without shunt. Conclusions: Nearly half of all patients with migraine with aura have a right-to-left shunt due to a patent foramen ovale. Shunt size is larger in migraineurs than controls. The clinical presentation of migraine is identical in patients with and without a patent foramen ovale.

An index to identify stroke-related vs incidental patent foramen ovale in cryptogenic stroke

Objective: We aimed to create an index to stratify cryptogenic stroke (CS) patients with patent foramen ovale (PFO) by their likelihood that the stroke was related to their PFO. Methods: Using data from 12 component studies, we used generalized linear mixed models to predict the presence of PFO among patients with CS, and derive a simple index to stratify patients with CS. We estimated the stratum-specific PFO-attributable fraction and stratum-specific stroke/TIA recurrence rates. Results: Variables associated with a PFO in CS patients included younger age, the presence of a cortical stroke on neuroimaging, and the absence of these factors: diabetes, hypertension, smoking, and prior stroke or TIA. The 10-point Risk of Paradoxical Embolism score is calculated from these variables so that the youngest patients with superficial strokes and without vascular risk factors have the highest score. PFO prevalence increased from 23% (95% confidence interval [CI]: 19%–26%) in those with 0 to 3 points to 73% (95% CI: 66%–79%) in those with 9 or 10 points, corresponding to attributable fraction estimates of approximately 0% to 90%. Kaplan-Meier estimated stroke/TIA 2-year recurrence rates decreased from 20% (95% CI: 12%–28%) in the lowest Risk of Paradoxical Embolism score stratum to 2% (95% CI: 0%–4%) in the highest. Conclusion: Clinical characteristics identify CS patients who vary markedly in PFO prevalence, reflecting clinically important variation in the probability that a discovered PFO is likely to be stroke-related vs incidental. Patients in strata more likely to have stroke-related PFOs have lower recurrence risk.

Stent Placement in Acute Cerebral Artery Occlusion Use of a Self-Expandable Intracranial Stent for Acute Stroke Treatment

Background and Purpose— Stent placement has been applied in small case series as a rescue therapy in combination with different thrombolytic agents, percutaneous balloon angioplasty (PTA), and mechanical thromboembolectomy (MT) in acute stroke treatment. These studies report a considerable mortality and a high rate of intracranial hemorrhages when balloon-mounted stents were used. This study was performed to evaluate feasibility, efficacy, and safety of intracranial artery recanalization for acute ischemic stroke using a self-expandable stent. Methods— All patients treated with an intracranial stent for acute cerebral artery occlusion were included. Treatment comprised intraarterial thrombolysis, thromboaspiration, MT, PTA, and stent placement. Recanalization result was assessed by follow-up angiography immediately after stent placement. Complications related to the procedure and outcome at 3 months were assessed. Results— Twelve patients (median NIHSS 14, mean age 63 years) were treated with intracranial stents for acute ischemic stroke. Occlusions were located in the posterior vertebrobasilar circulation (n=6) and in the anterior circulation (n=6). Stent placement was feasible in all procedures and resulted in partial or complete recanalization (TIMI 2/3) in 92%. No vessel perforations, subarachnoid, or symptomatic intracerebral hemorrhages occurred. One dissection was found after thromboaspiration and PTA. Three patients (25%) had a good outcome (mRS 0 to 2), 3 (25%) a moderate outcome (mRS 3), and 6 (50%) a poor outcome (mRS 4 to 6). Mortality was 33.3%. Conclusions— Intracranial placement of a self-expandable stent for acute ischemic stroke is feasible and seems to be safe to achieve sufficient recanalization.

Outcome of Stroke With Mild or Rapidly Improving Symptoms

Background and Purpose— Acute ischemic stroke with mild or rapidly improving symptoms is expected to result in good functional outcome, whether treated or not. Therefore, thrombolysis with its potential risks does not seem to be justified in such patients. However, recent studies indicate that the outcome is not invariably benign. Methods— We analyzed clinical and radiological data of patients with stroke who presented within 6 hours of stroke onset and did not receive thrombolysis because of mild or rapidly improving symptoms. Univariate and logistic regression analyses were performed to define predictors of clinical outcome. Results— One hundred sixty-two consecutive patients (110 men and 52 women) aged 63±13 years were included. The median National Institutes of Health Stroke Scale score on admission was 2 (range, 1 to 14). All patients presented within 6 hours of symptom onset. After 3 months, modified Rankin Scale score was ≤1 in 122 patients (75%), indicating a favorable outcome. Thirty-eight patients (23.5%) had an unfavorable outcome (modified Rankin Scale 2 to 5) and 2 patients (1.3%) had died. Baseline National Institutes of Health Stroke Scale score ≥10 points increased the odds of unfavorable outcome or death 16.9-fold (95% CI: 1.8 to 159.5; P<0.013), and proximal vessel occlusion increased the odds 7.13-fold (95% CI: 1.1 to 45.5; P<0.038). Conclusions— Seventy-five percent of patients with mild or rapidly improving symptoms will have a favorable outcome after 3 months. Therefore, a decision against thrombolysis seems to be justified in the majority of patients. However, selected patients, especially those with proximal vessel occlusions and baseline National Institutes of Health Stroke Scale scores ≥10 points, might derive a benefit from thrombolysis.

Mechanism of Ischemic Infarct in Spontaneous Carotid Dissection

Background and Purpose— It is unclear whether stroke in patients with spontaneous dissection of the cervical internal carotid artery (ICAD) is due to thromboembolism or impaired hemodynamics. This study investigated the mechanism of stroke in ICAD by examining brain imaging and cerebrovascular findings of such patients. Methods— We retrospectively evaluated the prospectively collected brain CT, MR, and ultrasound findings of 141 consecutive patients with 143 ICADs causing ischemic stroke. Eleven patients were not included because they had an inappropriate temporal bone window (n=6) or were treated with thrombolysis (n=5). Thus, the data of 130 patients (76 men, 54 women) with 131 ICADs were analyzed. Results— All patients had territorial infarcts; 6 patients (5%) also had border-zone infarct patterns. Territorial infarcts affected the middle cerebral artery (MCA) in 130 of 131 cases (99%) and the anterior cerebral artery (ACA) in 1 case (1%). Additional vascular territories were affected in 8 patients with MCA infarcts (ACA, n=5 [4%]; posterior cerebral artery, n=3 [2%]). The pattern (hemodynamic versus thromboembolic) and extent of infarction were not influenced by vascular findings (MCA stenosis or occlusion, ACA occlusion, degree of obstruction in the dissected ICA, pattern of cross-flow in 115 patients with >80% ICA stenosis or occlusion). Conclusions— This study suggests that thromboembolism, not hemodynamic infarction, is the essential stroke mechanism in ICAD.