Search

Background: The newly developed multi-frequency transcranial Doppler (TCD) is able to differentiate gaseous from solid emboli. Our goal was to apply this technology to initially characterize emboli detected during carotid stenting with distal protection. Methods: Patients undergoing carotid angiography and stenting were monitored with 2–2.5 MHz TCD (Embo-Dop, DWL) over the middle cerebral artery unilateral to stent deployment. Sonographers insured optimal signal recordings during the procedures. Automated emboli detection and classification software (MultiXLab version 2.0) was applied for offline count and analysis. Monitoring using the Filter Wire EX (Boston Scientific) and ACCUNET system (Guidant Corporation) was performed. Results: A total of 9,649 embolic signals were detected during 11 angiographic and 10 stenting procedures. An observer confirmed the signals using the International Consensus definition. Automated software classified these events into 5,900 gaseous and 3,749 solid emboli. During contrast injections without the protection device, 1,013 emboli were detected with 28% of these being solid. With deployment of the distal protection device, 8,636 emboli were found with 40% being solid (p < 0.001). During stenting and angioplasty with the protection device, 7,395 emboli with 42% solids were detected (p < 0.001). Finally injection of contrast after the procedure, with the protection device still deployed, yielded 1,241 emboli with 31% solids (NS). Only 1 patient developed transient hemiparesthesia during ballooning that reduced the flow velocity to zero for 14 s. Neither gaseous nor solid emboli resulted in a mean flow velocity decrease or clinical symptoms. Conclusions: Microembolization frequently occurs during stenting even with deployment of the distal protection device. More solid emboli are seen during manipulations associated with lesion crossing. Although novel TCD methods yield a high frequency of embolic signals, further validation of this technique to determine the true nature, size, and number of emboli is needed. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Although thrombolysis in patients with advanced age is considered more risky, some may benefit from TPA treatment. We studied safety and recanalization/recovery in patients older than 80 years treated with TPA and compared them with younger stroke patients. Methods: We studied patients treated with intravenous TPA and divided them into younger (<80 years) and older (≥80 years) groups for comparison. Diagnostic transcranial Doppler was completed before bolus, and patients were consequently monitored for up to 2 h when feasible. Clinical data included NIH Stroke Scale score, symptomatic intracranial hemorrhage (ICH) and discharge disposition. Results: We studied 127 younger (mean 63 years, range 31–79) and 56 older patients (mean 84 years, range 80–93). Median baseline NIH Stroke Scale score was higher in the older group (18 vs. 14 points, NS). Occlusion locations, onset to needle time (median 130 vs. 120 min) as well as improvement at 24 h (median 5 vs. 4 points) were similar in both groups. Transcranial Doppler monitoring showed similar partial or complete recanalization rates (66 vs. 66%), onset to recanalization time (median 160 vs. 158 min) and reocclusion rates (26 vs. 25%). Symptomatic and fatal ICH was not higher in the older group (7.1 and 3.5% vs. 6.3 and 3.9%, NS). There was higher mortality among older patients (20 vs. 11%, NS). At discharge, 23% of older patients went home, 41% underwent rehabilitation and 16% were transferred to skilled nursing facilities, compared with 31, 43 and 15% respectively, in the younger group. Conclusion: After intravenous TPA treatment, patients over 80 years of age have similar recanalization, short-term improvement and symptomatic ICH rates compared with younger patients. However, older patients tend to have higher in-hospital mortality. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Endogenous estrogens play an important role in the overall cardiocirculatory system. However, there are no studies exploring the hormone metabolism and signaling pathway genes together on ischemic stroke, including sulfotransferase family 1E (SULT1E1), catechol-O-methyl-transferase (COMT), and estrogen receptor α (ESR1). Methods: A case-control study was conducted on 305 young ischemic stroke subjects aged ≤ 50 years and 309 age-matched healthy controls. SULT1E1 -64G/A, COMT Val158Met, ESR1 c.454-397 T/C and c.454-351 A/G genes were genotyped and compared between cases and controls to identify single nucleotide polymorphisms associated with ischemic stroke susceptibility. Gene-gene interaction effects were analyzed using entropy-based multifactor dimensionality reduction (MDR), classification and regression tree (CART), and traditional multiple regression models. Results: COMT Val158Met polymorphism showed a significant association with susceptibility of young ischemic stroke among females. There was a two-way interaction between SULT1E1 -64G/A and COMT Val158Met in both MDR and CART analysis. The logistic regression model also showed there was a significant interaction effect between SULT1E1 -64G/A and COMT Val158Met on ischemic stroke of the young (P for interaction = 0.0171). We further found that lower estradiol level could increase the risk of young ischemic stroke for those who carry either SULT1E1 or COMT risk genotypes, showing a significant interaction effect (P for interaction = 0.0174). Conclusions: Our findings support that a significant epistasis effect exists among estrogen metabolic and signaling pathway genes and gene-environment interactions on young ischemic stroke subjects. [ABSTRACT FROM AUTHOR]

Background: The association between ischemic stroke and 2 single nucleotide polymorphisms (SNPs) on chromosome 12p13, rs12425791 and rs11833579 appears inconsistent across different samples. These SNPs are close to the ninjurin2 gene which may alter the risk of stroke by affecting brain response to ischemic injury. The purpose of this study was to investigate the association between these two SNPs and ischemic stroke risk, as well as prognostic outcomes in a Taiwanese sample. Methods: We examined the relations of these two SNPs to the odds of new-onset ischemic stroke, ischemic stroke subtypes, and to the one year risk of stroke-related death or recurrent stroke following initial stroke in a casecontrol study. A total of 765 consecutive patients who had first-ever ischemic stroke were compared to 977 strokefree, age-matched controls. SNPs were genotyped by Taqman fluorescent allelic discrimination assay. The association between ischemic stroke and SNPs were analyzed by multivariate logistic regression. Cox proportional hazard model was used to assess the effect of individual SNPs on stroke-related mortality or recurrent stroke. Results: There was no significant association between SNP rs12425791 and rs11833579 and ischemic stroke after multiple testing corrections. However, the marginal significant association was observed between SNP rs12425791 and large artery atherosclerosis under recessive model (OR, 2.30; 95%CI, 1.22-4.34; q-value = 0.062). Among the 765 ischemic stroke patients, 59 died or developed a recurrent stroke. After adjustment for age, sex, vascular risk factors and baseline stroke severity, Cox proportional hazard analysis indicated that the hazard ratios were 2.76 (95%CI, 1.34-5.68; q-value, 0.02) and 2.15 (95%CI, 1.15-4.02; q-value, 0.03) for individuals with homozygous variant allele of rs12425791 and rs11833579, respectively. Conclusions: This is a precedent study that found genetic variants of rs12425791 and rs11833579 on chromosome 12p13 are independent predictors of stroke-related mortality or stroke recurrence in patients with incident ischemic stroke in Taiwan. Further study is needed to explore the details of the physiological function and the molecular mechanisms underlying the association of this genetic locus with ischemic stroke. [ABSTRACT FROM AUTHOR]