Five-Year Risk of Acute Myocardial Infarction After Acute Ischemic Stroke in Korea

Background

The long‐term incidence of acute myocardial infarction (AMI) in patients with acute ischemic stroke (AIS) has not been well defined in large cohort studies of various race‐ethnic groups.

Methods and Results

A prospective cohort of patients with AIS who were registered in a multicenter nationwide stroke registry (CRCS‐K [Clinical Research Collaboration for Stroke in Korea] registry) was followed up for the occurrence of AMI through a linkage with the National Health Insurance Service claims database. The 5‐year cumulative incidence and annual risk were estimated according to predefined demographic subgroups, stroke subtypes, a history of coronary heart disease (CHD), and known risk factors of CHD. A total of 11 720 patients with AIS were studied. The 5‐year cumulative incidence of AMI was 2.0%. The annual risk was highest in the first year after the index event (1.1%), followed by a much lower annual risk in the second to fifth years (between 0.16% and 0.27%). Among subgroups, annual risk in the first year was highest in those with a history of CHD (4.1%) compared with those without a history of CHD (0.8%). The small‐vessel occlusion subtype had a much lower incidence (0.8%) compared with large‐vessel occlusion (2.2%) or cardioembolism (2.4%) subtypes. In the multivariable analysis, history of CHD (hazard ratio, 2.84; 95% CI, 2.01–3.93) was the strongest independent predictor of AMI after AIS.

Conclusions

The incidence of AMI after AIS in South Korea was relatively low and unexpectedly highest during the first year after stroke. CHD was the most substantial risk factor for AMI after stroke and conferred an approximate 5‐fold greater risk.

Microbleeds and Outcome in Patients With Acute Ischemic Stroke and Atrial Fibrillation Taking Anticoagulants

Background and Purpose:

We investigated the impact of the presence, burden, and location of cerebral microbleeds (CMBs) on the risk of major adverse cerebrovascular and cardiovascular events (MACCE) in patients with acute ischemic stroke and atrial fibrillation treated with oral anticoagulants (OACs). We also examined whether the clinical effect of CMBs differs according to the type of OACs.

Methods:

A total of 1742 patients with acute ischemic stroke and atrial fibrillation treated with OACs were enrolled in this cohort study. The primary composite outcome was the occurrence of MACCE (a composite of stroke, acute myocardial infarction, or vascular death) over a 2-year period according to CMB status.

Results:

CMB presence was significantly associated with the risk of future MACCE (hazard ratio, 1.89 [95% CI, 1.23–2.88]; P =0.003) after adjustment for confounders in patients with acute ischemic stroke and atrial fibrillation taking OACs. Patients with exactly 1 CMB had a similar rate of MACCE compared with those without CMBs ( P =0.461). However, patients with multiple CMBs (≥2), particularly high burden CMBs (≥5), had a significantly higher proportion of MACCE. Both CMB-positive groups with lobar and deep CMB had more frequent MACCE than the CMB-negative group, and the rate of MACCE was not different according to CMB location. In patients treated with warfarin, CMB was significantly associated with a risk of MACCE ( P =0.002), but not in patients treated with direct OACs ( P =0.517).

Conclusions:

The study results indicate that the risk of future MACCE increased with increasing CMB burden in patients with AIS and atrial fibrillation taking OACs, while the anatomic location of CMBs did not influence the risk of future MACCE. This risk seemed to be more apparent in patients taking warfarin.

Risk factors and renal outcomes of low bone mineral density in patients with non-dialysis chronic kidney disease

Bone disorder is a common complication of chronic kidney disease (CKD). The clinical usefulness of bone mineral density (BMD) in CKD is not well known. Our study shows that low BMD is associated with physical activity and dietary Na/K intake ratio and can predict poor renal outcome in non-dialysis CKD.

PURPOSE

Despite evidence of a link between bone mineral disorders and chronic kidney disease (CKD), the clinical implications of bone mineral density (BMD) in CKD are not well established. We investigated risk factors and renal outcomes of low BMD in CKD.

METHODS

We analyzed data from the KNOW-CKD. BMD measured by dual-energy x-ray absorptiometry was classified by T score: normal (T score ≥ - 1.0), osteopenia (- 1.0 > T score > - 2.5), and osteoporosis (T score ≤ - 2.5) of the lumbar spine, hip, or femoral neck. Logistic regression analysis to assess risk factors of low BMD (T score < - 1.0) and Cox proportional hazards models to estimate risk of incident end-stage renal disease (ESRD).

RESULTS

Low BMD was prevalent (osteopenia 33%; osteoporosis 8%) in 2128 adults with CKD (age 54 ± 12 years; male 61%). Over a median follow-up of 4.3 years, there were 521 cases of incident ESRD. Lower BMD was associated with female sex, older age, low eGFR, low BMI, and lifestyle factors of physical activity (odds ratio (OR) = 0.62, 95% confidence interval (0.49-0.77)) and spot urine Na/K ratio (1.07 (1.00-1.15)). In adjusted Cox models, low BMD was associated with increased incident ESRD (hazard ratio (HR) = 1.14 (0.92-1.41) for osteopenia; 1.43 (1.01-2.04) for osteoporosis, P for trend < 0.05) compared with the reference of normal BMD. The association between low BMD and ESRD was similar according to T score discordance classification.

CONCLUSIONS

Low BMD was associated with modifiable lifestyle factors including low physical activity and high dietary Na/K intake ratio. The presence of low BMD is associated with poor renal outcomes in non-dialysis CKD.

Comparative Effectiveness of Dual Antiplatelet Therapy With Aspirin and Clopidogrel Versus Aspirin Monotherapy in Mild-to-Moderate Acute Ischemic Stroke According to the Risk of Recurrent Stroke: An Analysis of 15 000 Patients From a Nationwide, Multicenter Registry

BACKGROUND

This study compared the effectiveness of dual antiplatelet therapy (DAPT) with clopidogrel-aspirin with that of aspirin monotherapy (AM) in mild-to-moderate acute ischemic stroke considering the risk of recurrent stroke using the Stroke Prognosis Instrument II (SPI-II) score.

METHODS

This study is a retrospective analysis of data from a prospective, nationwide, multicenter stroke registry database between January 2011 and July 2018. We included patients with mild-to-moderate (National Institutes of Health Stroke Scale score ≤10), acute (within 24 hours of onset), noncardioembolic ischemic stroke. The primary outcome was a 3-month composite of stroke (either hemorrhagic or ischemic), myocardial infarction, and all-cause mortality. Propensity scores using the inverse probability of treatment weighting method were used to mitigate baseline imbalances between the DAPT and AM groups and within each subgroup considering SPI-II scores.

RESULTS

Among the 15 430 patients (age, 66±13 years; men, 62.0%), 45.1% (n=6960) received DAPT and 54.9% (n=8470) received AM. Primary outcome events were significantly more frequent in the AM group (16.7%) than in the DAPT group (15.5%; P=0.03). Weighted Cox proportional hazards models showed a reduced risk of 3-month primary vascular events in the DAPT group versus the AM group (hazard ratio, 0.84 [0.78-0.92]; P<0.001), with no interaction between acute treatment type and SPI-II risk subgroups (P_interaction=0.44). However, among the high-risk patients with SPI-II scores >7, a substantially larger absolute benefit was observed for 3-month composite vascular events in the DAPT group (weighted absolute risk differences, 5.4%), whereas smaller absolute benefits were observed among patients in the low- or medium-risk SPI-II subgroups (1.7% and 2.4%, respectively).

CONCLUSIONS

Treatment with clopidogrel-aspirin was associated with a reduction in 3-month vascular events compared with AM in mild-to-moderate acute noncardioembolic ischemic stroke patients. Larger magnitudes of the effects of DAPT with clopidogrel-aspirin were observed in the high-risk subgroup by SPI-II risk scores.

Neurologic deterioration in patients with acute ischemic stroke or transient ischemic attack

OBJECTIVE

To improve epidemiologic knowledge of neurologic deterioration (ND) in patients with acute ischemic stroke (AIS).

METHODS

In this prospective observational study, we captured ND prospectively in 29,446 patients with AIS admitted to 15 hospitals in Korea within 7 days of stroke onset. ND was defined as an increase in NIH Stroke Scale (NIHSS) score ≥2 (total), or ≥1 (motor or consciousness), or any new neurologic symptoms. Change in incidence rate after stroke onset, causes, factors associated with ND, modified Rankin Scale (mRS) score at 3 months and 1 year, and a composite of stroke, myocardial infarction, and all-cause death at 1 year were assessed.

RESULTS

ND occurred in 4,299 (14.6%) patients. The highest rate, 6.95 per 1,000 person-hours incidence, was within the first 6 hours, which decreased to 2.09 within 24-48 hours, and 0.66 within 72-96 hours after stroke onset. Old age, female sex, diabetes, early arrival, large artery atherosclerosis as a stroke subtype, high NIHSS scores, glucose level, systolic blood pressure, leukocytosis at admission, recanalization therapy, TIA without a relevant lesion, and steno-occlusion of relevant arteries were associated with ND. The causes were stroke progression (71.8%) followed by recurrence (8.5%). Adjusted relative risks (95% CI) for poor outcome (mRS 3-6) at 3 months and 1 year were 1.75 (1.70-1.80) and 1.70 (1.65-1.75), respectively. The adjusted hazard ratio (95% CI) for the composite event was 1.59 (1.45-1.74).

CONCLUSIONS

ND should be taken into consideration as a factor that may influence the outcome in acute ischemic stroke.

Statin Effects in Atrial Fibrillation-Related Stroke: A Systematic Review and Meta-Analysis

Background: Statins lower the risk of recurrent stroke and mortality and improve outcomes in patients with ischemic stroke. However, the effects of statins on atrial fibrillation (AF)-related stroke are not well-established. Our study aims to investigate the effects of statin therapy on the clinical outcomes in patients with AF-related stroke.

Methods: Electronic databases (MEDLINE, Embase, and Scopus) were searched for previous studies on the effects of pre- and post-stroke statins on the clinical outcomes in AF-related stroke patients. The primary outcome was all-cause mortality. Secondary outcomes included recurrent ischemic stroke, acute coronary events, major adverse cardiovascular events (MACE), and short-term functional outcomes. We extracted hazard ratios (HRs) or odds ratios (ORs) with 95% confidence interval (CI) from each study and pooled them through a meta-analysis.

Results: A total of eight studies (five on post-stroke statins and three on pre-stroke statins) with 12,216 patients were included in the analysis. Post-stroke statin therapy reduced the risk of all-cause mortality (HR, 0.63; 95% CI, 0.55–0.74). This beneficial effect was sustained regardless of statin intensity. However, no significant associations were observed between statin therapy and a reduction in the risk of recurrent ischemic stroke, acute coronary events, or MACE. Pre-stroke statin use was associated with a lower risk of poor short-term functional outcomes (OR, 0.63; 95% CI, 0.47–0.85).

Conclusions: Statin therapy for AF-related stroke may reduce all-cause mortality and improve functional outcomes. Randomized controlled studies are warranted to confirm the effects of statins on the outcomes of AF-related stroke.

Effectiveness of Adding Antiplatelets to Oral Anticoagulants in Patients with Acute Ischemic Stroke with Atrial Fibrillation and Concomitant Large Artery Steno-Occlusion

We investigated the effectiveness of adding antiplatelet (AP) to oral anticoagulant (OAC) treatment versus OAC treatment alone in patients with AIS with atrial fibrillation (AF) and significant large artery steno-occlusion (LASO). This study is a retrospective analysis of a nationwide, prospective, multicenter stroke registry between April 2008 and November 2017. Patients with acute (within 48 h of onset) and mild-to-moderate (NIHSS score ≤ 15) stroke with AF and concomitant LASO were identified. Antithrombotic regimens at discharge were categorized into OAC alone or OAC + AP. The primary outcome event was a composite of recurrent stroke, myocardial infarction, and all-cause mortality within 3 months of stroke. Among the 2553 patients (age, 73 ± 10 years; men, 50.4%), 78.8% were treated with OAC alone, and 21.2% were treated with OAC + AP. The primary outcome events were significantly more common in the OAC + AP group (6.7%) than the OAC alone group (4.3%) (p = 0.02). Weighted Cox proportional hazard analysis showed that OAC + AP increased the risk of 3-month primary outcome events compared with OAC alone (HR, 1.62 [1.06 to 2.46]). A potential interaction between the type of LASO and discharge antithrombotics was suggested (P_interaction = 0.04); unlike in patients with complete occlusion (OAC + AP; HR, 2.00 [1.27-3.15]), OAC + AP was comparable with OAC alone for 3-month primary outcome in patients with moderate-to-severe stenosis (HR, 0.54 [0.17-1.70]). In conclusion, OAC + AP might increase the risk of 3-month outcome events compared with OAC alone in patients with AIS with AF and concomitant LASO. However, the effect of additional AP to OAC might differ according to LASO type.

Statin therapy in acute cardioembolic stroke with no guidance-based indication

Objective

It is uncertain whether patients with cardioembolic stroke and without a guidance-based indication for statin therapy should be administered a statin for prevention of subsequent vascular events. This study was performed to determine whether the statin therapy is beneficial in preventing major vascular events in this population.

Methods

Using a prospective multicenter stroke registry database, we identified patients with acute cardioembolic stroke who were hospitalized between 2008 and 2015. Patients who had other established indications for statin therapy according to current guidelines were excluded. Major vascular event was defined as a composite of stroke recurrence, myocardial infarction, and vascular death. We performed frailty model analysis with the robust sandwich variance estimator using the stabilized inverse probability of treatment weighting method to estimate hazard ratios of statin therapy on outcomes.

Results

Of 6,124 patients with cardioembolic stroke, 2,888 (male 44.6%, mean age 75.3 years, 95% confidence interval [CI] 74.8–75.8) were eligible, and 1,863 (64.5%) were on statin therapy during hospitalization. After a median follow-up of 359 days, cumulative incidences of major vascular events were 9.3% in the statin users and 20.5% in the nonusers (p < 0.001 by log-rank test). The adjusted hazard ratios of statin therapy were 0.39 (95% CI 0.31–0.48) for major vascular events, 0.81 (95% CI 0.57–1.16) for stroke recurrence, 0.28 (95% CI 0.21–0.36) for vascular death, and 0.53 (95% CI 0.45–0.61) for all-cause death.

Conclusion

Starting statin during the acute stage of ischemic stroke may reduce the risk of major vascular events, vascular death, and all-cause death in patients with cardioembolic stroke with no guidance-based indication for statin.

Development of stroke identification algorithm for claims data using the multicenter stroke registry database

BACKGROUND

Identifying acute ischemic stroke (AIS) among potential stroke cases is crucial for stroke research based on claims data. However, the accuracy of using the diagnostic codes of the International Classification of Diseases 10th revision was less than expected.

METHODS

From the National Health Insurance Service (NHIS) claims data, stroke cases admitted to the hospitals participating in the multicenter stroke registry (Clinical Research Collaboration for Stroke in Korea, CRCS-K) during the study period with principal or additional diagnosis codes of I60-I64 on the 10th revision of International Classification of Diseases were extracted. The datasets were randomly divided into development and validation sets with a ratio of 7:3. A stroke identification algorithm using the claims data was developed and validated through the linkage between the extracted datasets and the registry database.

RESULTS

Altogether, 40,443 potential cases were extracted from the NHIS claims data, of which 31.7% were certified as AIS through linkage with the CRCS-K database. We selected 17 key identifiers from the claims data and developed 37 conditions through combinations of those key identifiers. The key identifiers comprised brain CT, MRI, use of tissue plasminogen activator, endovascular treatment, carotid endarterectomy or stenting, antithrombotics, anticoagulants, etc. The sensitivity, specificity, and diagnostic accuracy of the algorithm were 81.2%, 82.9%, and 82.4% in the development set, and 80.2%, 82.0%, and 81.4% in the validation set, respectively.

CONCLUSIONS

Our stroke identification algorithm may be useful to grasp stroke burden in Korea. However, further efforts to refine the algorithm are necessary.

Three-month modified Rankin Scale as a determinant of 5-year cumulative costs after ischemic stroke

Objective

Stroke is a devastating and costly disease; however, there is a paucity of information on long-term costs and on how they differ according to 3-month modified Rankin scale (mRS) score, which is a primary outcome variable in acute stroke intervention trials.

Methods

We analyzed a prospective multicenter stroke registry (Clinical Research Collaboration for Stroke in Korea) database through linkage with claims data from the National Health Insurance Service with follow-up to December 2016. Healthcare expenditures were converted into daily cost individually, and annual and cumulative costs up to 5 years were estimated and compared according to the 3-month mRS score.

Results

Between January 2011 and November 2013, 11,136 patients were enrolled in the study. The mean age was 68 years, and 58% were men. The median follow-up period was 3.9 years (range 0–5 years). Mean cumulative cost over 5 years was $117,576 (US dollars [USD]); the cost in the first year after stroke was the highest ($38,152 USD), which increased markedly from the cost a year before stroke ($8,718 USD). The mean 5-year cumulative costs differed significantly according to the 3-month mRS score (p < 0.001); the costs for a 3-month mRS score of 0 or 5 were $53,578 and $257,486 USD, respectively. Three-month mRS score was an independent determinant of long-term costs after stroke.

Conclusions

We show that 3-month mRS score plays an important role in the prediction of long-term costs after stroke. Such estimates relating to 3-month mRS categories may be valuable when undertaking health economic evaluations related to stroke care.

Abstract TP435: Oral Anticoagulant Therapy Adherent to ESC Guidelines Reduces the Risk of Recurrent Stroke in Patients With Atrial Fibrillation

Introduction: Oral anticoagulant therapy is the primary treatment for the prevention of recurrent ischemic stroke in patients with atrial fibrillation (AF). Early anticoagulant therapy can be beneficial for the prevention of recurrent ischemic stroke, however, also can provoke symptomatic intracranial hemorrhage. This study aims to evaluate the efficacy and safety of standard oral anticoagulant therapy adherent to the European Society of Cardiology (ESC) guidelines compared to early oral anticoagulant therapy.

Methods: Acute ischemic stroke patients with AF were included from a nationwide multicenter registry (K-ATTENTION). The primary outcome was recurrent all-type stroke during 90 days of follow-up. Secondary outcomes were major adverse cardiovascular events (MACE), ischemic stroke, intracranial hemorrhage, acute coronary syndrome, all-cause death, and major hemorrhage. The propensity score was used to match the baseline characteristics between the two treatment groups.

Results: Among 2,321 eligible patients, 532 patients with standard anticoagulation were matched to 532 patients with early anticoagulation. Eight participants (1.5%) with standard anticoagulation had recurrence of all-type stroke compared with 19 (3.5%) of participants with early anticoagulation (odds ratio [OR], 0.41; 95% confidence interval [CI], 0.18-0.95; P=0.038). Standard anticoagulation was also associated with reduced risk of recurrent ischemic stroke (OR, 0.30; 95% CI, 0.11-0.82; P=0.019). Other secondary outcomes, including intracranial hemorrhage and major hemorrhage, appeared not to be informative.

Conclusions: In conclusion, standard oral anticoagulant therapy adherent to ESC guidelines reduces the risk of recurrent all-type stroke and ischemic stroke compared to early oral anticoagulant therapy.

ACOX3 Dysfunction as a Potential Cause of Recurrent Spontaneous Vasospasm of Internal Carotid Artery

Recurrent spontaneous vasospasm of the extracranial internal carotid artery (RSV-eICA) is a rarely recognized cause of ischemic stroke in young adults. However, its pathophysiology remains largely unknown. Through whole-exome sequencing of the ACOX3 gene of two dizygotic Korean twin brothers affected by RSV-eICA, we identified two compound heterozygous missense variants c.235 T > G (p.F79 V) and c.665G > A (p.G222E). In silico analysis indicated that both variants were classified as pathogenic. In vitro ACOX3 enzyme assay indicated practically no enzyme activity in both F79 V and G222E mutants. To determine the effect of the mutants on vasospasm, we used a collagen contraction assay on human aortic smooth muscle cells (HASMC). Carbachol, a cholinergic agonist, induces contraction of HASMC. Knockdown of ACOX3 in HASMC, using siRNA, significantly repressed HASMC contraction triggered by carbachol. The carbachol-induced HASMC contraction was restored by transfection with plasmids encoding siRNA-resistant wild-type ACOX3, but not by transfection with ACOX3 G222E or by co-transfection with ACOX3 F79 V and ACOX3 G222E, indicating that the two ACOX3 mutants suppress carbachol-induced HASMC contraction. We propose that an ACOX3 dysfunction elicits a prolonged loss of the basal aortic myogenic tone. As a result, smooth muscles of the ICA's intermediate segment, in which the sympathetic innervation is especially rich, becomes hypersensitive to sympathomimetic stimuli (e.g., heavy exercise) leading to a recurrent vasospasm. Therefore, ACOX3 dysfunction would be a causal mechanism of RSV-eICA. For the first time, we report the possible involvement of ACOX3 in maintaining the basal myogenic tone of human arterial smooth muscle.

Effect of Heart Rate on Stroke Recurrence and Mortality in Acute Ischemic Stroke With Atrial Fibrillation

Background and Purpose—

There is a paucity of information about the role of resting heart rate in the prediction of outcome events in patients with ischemic stroke with atrial fibrillation. We aimed to investigate the relationships between the level and variability of heart rate in the acute stroke period and stroke recurrence and mortality after acute ischemic stroke in patients with atrial fibrillation.

Methods—

Acute patients with ischemic stroke who had atrial fibrillation and were hospitalized within 48 hours of stroke onset were identified from a multicenter prospective stroke registry database. The acute stroke period was divided into early (within 24 hours of hospitalization) and late (72 hours to 7 days from onset) stages, and data on heart rate in both stages were collected. Moreover, the level and variability of heart rate were assessed using mean values and coefficients of variation. Outcome events were prospectively monitored up to 1 year after the index stroke.

Results—

Among 2046 patients eligible for the early acute stage analysis, 102 (5.0%) had a stroke recurrence, and 440 (21.5%) died during the first year after stroke. A statistically significant nonlinear J-shaped association was observed between mean heart rate and mortality ( P <0.04 for quadratic and overall effect) but not between mean heart rate and stroke recurrence ( P >0.1 for quadratic and overall effect). The nonlinear and overall effects of the coefficients of variation of heart rate were not significant for all outcome variables. The same results were observed in the late acute stage analysis (n=1576).

Conclusions—

In patients with atrial fibrillation hospitalized for acute ischemic stroke, the mean heart rate during the acute stroke period was not associated with stroke recurrence but was associated with mortality (nonlinear, J-shaped association). The relationships between heart rate and outcomes were not observed with respect to heart rate variability.

Effect of Statin Therapy on Outcomes of Patients With Acute Ischemic Stroke and Atrial Fibrillation

Background

There is insufficient evidence on the effect of statins, particularly high‐intensity statins, in patients with acute ischemic stroke and atrial fibrillation. We investigated the impact of statins on the outcomes in these patients, including those who might be vulnerable to statin therapy and those without clinical atherosclerotic cardiovascular diseases.

Methods and Results

A total of 2153 patients with acute ischemic stroke and atrial fibrillation were enrolled in the present nationwide, multicenter, cohort study. The primary composite end point was the occurrence of net adverse clinical and cerebral events (NACCE; death from any cause, stroke, acute coronary syndrome, or major bleeding) over a 3‐year period based on statin intensity. NACCE rates were lower in patients receiving low‐ to moderate‐intensity (adjusted hazard ratio 0.64; 95% CI: 0.52‐0.78) and high‐intensity statins (hazard ratio 0.51; 95% CI 0.40‐0.66) than in those not receiving statin therapy. High‐intensity statins were associated with a lower risk for NACCE than low‐ to moderate‐intensity statins (hazard ratio 0.76; 95% CI 0.59‐0.96). Subgroup analyses showed that the differences in hazard ratio for 3‐year NACCE favored statin use across all subgroups, including older patients, those with low cholesterol levels, patients receiving anticoagulants, and patients without clinical atherosclerotic cardiovascular diseases. Magnified benefits of high‐intensity statins compared with low‐ to moderate‐intensity statins were observed in patients who underwent revascularization therapy and those under 75 years of age.

Conclusions

Statins, particularly high‐intensity statins, could reduce the risk for NACCE in patients with acute ischemic stroke and atrial fibrillation; this needs to be further explored in randomized controlled trials.

Characteristics and Factors for Short-Term Functional Outcome in Stroke Patients With Atrial Fibrillation, Nationwide Retrospective Cohort Study

Background and aims: Atrial fibrillation (AF) is a major cause of ischemic stroke; however, detailed clinical data and prognostic factors for stroke patients with AF are lacking in Korea. We aimed to investigate clinical information and factors associated with functional outcomes of stroke patients with AF from the Korean nationwide ATrial fibrillaTion EvaluatioN regisTry in Ischemic strOke patieNts (K-ATTENTION) database.

Methods: From January 2013 to December 2015, consecutive clinical information from acute stroke patients with AF or history of AF was collected from 11 centers in Korea. Collected data included demographics, risk factors, pre-stroke medication, stroke severity, stroke subtypes, concomitant cerebral atherosclerosis, brain image findings, recanalization therapy, discharge medication, and functional outcome at 3 months after index stroke.

Results: A total of 3,213 stroke patients (mean age, 73.6 ± 9.8 years; female, 48.6%) were included. The mean CHA₂DS₂-VASc score was 4.9. Among the 1,849 (57.5%) patients who had brain image and functional outcome data, poor outcome (modified Rankin scale > 2) was noted in 53.1% (981/1,849) of patients. After adjusting for age, sex, and variables that had a p < 0.05 in univariate analysis or well-known factors for functional outcome, presence of asymptomatic extracranial cerebral atherosclerosis [odd ratio (OR): 1.96, 95% confidence interval (CI): 1.36–2.82, p = 0.001] and less frequent prior stroke statin intake (OR: 0.69, 95% CI: 0.49–0.98, p = 0.038) were associated with poor functional outcome.

Conclusion: Our results suggest that presence of non-relevant extracranial cerebral atherosclerosis may affect poor functional outcome and prior stroke statin therapy may be feasible in Korean stroke patients with AF.

Magnetic Resonance Imaging Versus Computed Tomography Angiography Based Selection for Endovascular Therapy in Patients With Acute Ischemic Stroke

Background and Purpose- Randomized trials comparing the use of multimodal magnetic resonance imaging (MRI) to multimodal computed tomography (CT)/ CT angiography (CTA) for selecting candidates for endovascular therapy (EVT) have not been reported. This study aimed to elucidate whether MRI-based selection for EVT is safe and effective within and after a 6-hour time window compared with conventional CTA-based selection. Methods- Data from a prospective, nationwide, multicenter stroke registry were analyzed. Workflow timelines were compared between patients selected for EVT based on MRI (the MRI group) and CTA (the CTA group). Multivariable ordinal and binary logistic regression analyses were performed to explore the relationships between decision imaging for EVT and clinical outcomes, including good and excellent outcomes (modified Rankin Scale scores of 0-2 and 0-1, respectively) at 3-month, modified Rankin Scale score distributions and safety outcomes (symptomatic intracranial hemorrhage [SICH] and mortality). Results- Ultimately, 1265 patients (age, 69±12 yrs; men, 55%) were enrolled in this study. The median National Institutes of Health Stroke Scale score was 15 (11-19). All workflow time metrics were significantly delayed in the MRI group compared with the CTA group. There was no difference in good 3-month outcomes in patients arriving within 6 hours of onset between the MRI and CTA groups (38.1% versus 38.5%), but SICH and mortality rates were lower in the MRI group than the CTA group (3.8% versus 7.7%, P=0.01 for SICH; 15.4% versus 20.9%, P=0.04 for mortality). In the multivariable analysis, decision imaging was not significantly associated with 3-month functional outcomes (all P>0.1) or mortality ( P=0.051); however, the MRI group was less likely to develop SICH than the CTA group ( P=0.01; odds ratio, 0.34 [95% CI, 0.17-0.77]). Conclusions- Our study found MRI-based selection for EVT was not associated with improving functional outcome compared with CT-based selection, but may be better at reducing the risk of SICH, despite the delays in all workflow time metrics.

Comparative Effectiveness of Dual Antiplatelet Therapy With Aspirin and Clopidogrel Versus Aspirin Monotherapy in Acute, Nonminor Stroke: A Nationwide, Multicenter Registry-Based Study

Background and Purpose- This study aimed to compare the effectiveness of dual antiplatelet therapy with clopidogrel plus aspirin (DAPT) with that of aspirin monotherapy (AM) in patients with acute, nonminor, and noncardioembolic stroke. Methods- Using a prospective, nationwide, multicenter stroke registry database, acute (within 24 hours of onset), nonminor (baseline National Institutes of Health Stroke Scale score, 4-15), and noncardioembolic stroke patients were identified. Propensity scores using inverse probability of treatment weighting were used to adjust baseline imbalances between the DAPT and AM groups. A primary outcome measure was a composite of all types of stroke (ischemic and hemorrhagic), myocardial infarction, and all-cause mortality within 3 months of stroke onset. Results- Among the 4461 patients meeting the eligibility criteria (age, 69±13 years; men, 57.7%), 52.5% (n=2340) received AM, and 47.5% (n=2121) received DAPT. The primary outcome event was not significantly different between the DAPT group and the AM group (20.9% versus 22.6%, P=0.13). The event rates of all types of stroke were also not different between the 2 groups (19.3% versus 20.1%, P=0.35), while all-cause mortality was significantly lower in the DAPT group than in the AM group (3.4% versus 4.9%, P=0.02). In the propensity-weighted Cox proportional hazards models with robust estimation, DAPT did not reduce the risk of the primary outcome event (hazards ratio, 0.91; 95% CI, 0.79-1.04) but did reduce the risk of all-cause mortality (0.69; 0.49-0.97). There was no treatment heterogeneity among the predefined subgroups, although the potential benefits of DAPT were suggested in subpopulations of moderate-to-severe relevant arterial stenosis and relatively severe deficits (National Institutes of Health Stroke Scale score, 12-15). Conclusions- Compared to AM, clopidogrel plus aspirin did not reduce the risk of the primary outcome event during the first 3 months after a nonminor, noncardioembolic, ischemic stroke.

P5989Effect of neprilysin inhibitor for ischemic mitral regurgitation after myocardial injury

Background

After myocardial infarction (MI), mitral valve (MV) tethering and fibrosis stimulate functional mitral regurgitation (MR), resulting in high morbidity of heart failure and cardiac mortality. However, pharmacological treatment has not been proven effective in reducing ischemic MR. MV change post-MI is associated with an excessive endothelial-to-mesenchymal transition (EMT) by transforming growth factor (TGF)-β overexpression and also with left ventricular (LV) remodeling. In a recent clinical study using echocardiography, angiotensin receptor neprilysin inhibitor (ARNI) reduced functional MR to a greater extent than did valsartan, but the mechanism was not revealed.

Purpose

This study tested the hypothesis that treatment of neprilysin inhibitor attenuates functional MR after MI by facilitating LV reverse remodeling and suppressing EMT which mitigates inadequate leaflet adaptation.

Methods

In male Sprague-Dawley rats (n=31), functional MR was induced by occluding the left circumflex coronary artery. Two weeks after MI, MR and LV dilatation were confirmed by echocardiography and magnetic resonance imaging (MRI). Rats were randomly assigned to LCZ696 treatment (ARNI, 60 mg/kg/d, n=10), valsartan treatment (30mg/kg/d, n=10), or corn oil only (MR control group; n=11). After 6 weeks, LV volumes, functions and MR extent were quantified by using echocardiography, cardiac MRI and pressure-volume loop analysis. Also, excised mitral leaflets and LV were analyzed by histopathology and primary cultured valvular endothelial cells (VECs) were evaluated focusing on molecular changes.

Results

LCZ696 significantly attenuated post-MI LV dilatation after 6 weeks when compared with the control group (LV end-diastolic volume (EDV), 461.3±41.3 uL versus 525.1±78.2 uL; p<0.05), while valsartan did not (LV EDV, 471.2±26.8 uL; p>0.05 to control). There were no significant differences in the change of arterial pressure and ejection fraction between the treatment groups, however, dP/dt was greater in the LCZ696 group than in the MR control group (8203±286 mmHg/s for LCZ696 versus 6936±555 mmHg/s for MR control; p=0.01). MR extent and LA volume were significantly decreased in the LCZ696 group compared with the valsartan group. Pathological analysis showed that fibrosis was more prominent in the MR control than in the LCZ696 group. LCZ696 strongly reduced leaflet thickness, TGF-β, and downstream phosphorylated extracellular-signal-regulated kinase and EMT (25.4±11.8% vs. 53.4±12.6% α-smooth muscle actin-positive VECs; p<0.05). Leaflet area increased comparably (5%) in the LCZ696 group compared with the valsartan group.

Conclusions

Neprilysin inhibitor has positive effects on LV reverse remodeling and also directly modulates profibrotic changes of MV leaflets post-MI without eliminating adaptive growth. Understanding the mechanisms could provide new opportunities to ARNI reducing ischemic MR.

Acknowledgement/Funding

This work was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2014R1A6A3A04056205). It was also

P1711The association of multidisciplinary team approach with clinical outcomes in patients with acute myocardial infarction underwent veno-arterial extracorporeal membrane oxygenation

Background

Multidisciplinary team approach is necessary for the management of critically-ill patients. However, limited data are available on the impact of specialized extracorporeal membrane oxygenation (ECMO) team on clinical outcomes in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock.

Objectives

This study aimed to identify whether specialized ECMO team is associated with improved in-hospital mortality in AMI patients underwent venoarterial ECMO.

Methods

A total of 255 AMI patients underwent venoarterial ECMO from May 2004 to July 2018 were enrolled. In January 2014, multidisciplinary ECMO team was founded at our institution. Eligible patients were classified into pre-ECMO team group (n=131) and post-ECMO team group (n=124). The primary outcome was in-hospital mortality.

Results

In-hospital mortality (54.2% vs. 33.9%, p=0.002) and cardiac intensive care unit mortality (45.0% vs. 25.0%, p=0.001) were significantly lower after the implantation of multidisciplinary ECMO team (pre ECMO team vs. post-ECMO team). On binary logistic regression model, the multidisciplinary ECMO team approach was associated with lower risk of in-hospital mortality (odds ratio 0.36, 95% confidence interval 0.19–0.67, p=0.001). Incidence of all-cause mortality (58.3% vs. 35.2%, p<0.001) and rehospitalization due to heart failure (28.2% vs. 6.4%, p=0.001) at 6-months follow-up were also significantly lower in the post-ECMO team group than in the pre-ECMO team group.

Clinical outcomes Variables Total (N=255) Pre-ECMO team (N=131) Post-ECMO team (N=124) P value In-hospital mortality 113 (44.3) 71 (54.2) 42 (33.9) 0.002 Cardiovascular death 90 (35.3) 59 (45.0) 31 (25.0) 0.001 Noncardiovascular death 23 (9.0) 12 (9.2) 11 (8.9) >0.99 Cardiac intensive care unit mortality 106 (41.6) 68 (51.9) 38 (30.6) 0.001 Successful weaning of ECMO 169 (66.3) 75 (57.3) 94 (75.8) 0.002 Data are presented as n (%). Abbreviations: ECMO, extracorporeal membrane oxygenation.

Incidence of death, readmission for HF

Conclusions

The multidisciplinary ECMO team approach was associated with improved clinical outcomes in AMI patients complicated by cardiogenic shock. Our data support that specialized ECMO team is indispensable to improve outcomes in patients with AMI with refractory cardiogenic shock.

Baseline D-Dimer Levels as a Risk Assessment Biomarker for Recurrent Stroke in Patients with Combined Atrial Fibrillation and Atherosclerosis

Background: We investigated the effect of D-dimer levels and efficacy of different antithrombotic therapies according to the baseline D-dimer levels on recurrent stroke in patients with atrial fibrillation (AF)-related stroke and atherosclerosis. Methods: We enrolled 1441 patients with AF-related stroke and atherosclerosis in this nationwide multicenter study. The primary outcome measure was the occurrence of recurrent ischemic stroke over a 3-year period. Results: High D-dimer levels (≥2 μg/mL) were significantly associated with higher risk of recurrent ischemic stroke (adjusted hazard ratio (HR), 1.80; 95% confidence interval (CI), 1.13–2.84; p = 0.012). The risk of recurrent stroke was similar between the anticoagulant and the antiplatelet groups in all subjects (adjusted HR, 0.78; 95% CI, 0.46–1.32; p = 0.369). However, in patients with high D-dimer levels (≥2 μg/mL), risk of recurrent stroke was significantly lower in the anticoagulant group than in the antiplatelet group (adjusted HR, 0.40; 95% CI, 0.18–0.87; p = 0.022). Conclusion: Our findings suggested that baseline D-dimer levels could be used as a risk assessment biomarker of recurrent stroke in patients with AF-related stroke and atherosclerosis. High D-dimer levels would facilitate the identification of patients who are more likely to benefit from anticoagulants to ensure secondary prevention of stroke.

White matter hyperintensity load on stroke recurrence and mortality at 1 year after ischemic stroke

Objective

To define the role and risks associated with white matter hyperintensity (WMH) load in a stroke population with respect to recurrent stroke and mortality after ischemic stroke.

Methods

A total of 7,101 patients at a network of university hospitals presenting with ischemic strokes were followed up for 1 year. Multivariable Cox proportional hazards model and competing risk analysis were used to examine the independent association between quartiles of WMH load and stroke recurrence and mortality at 1 year.

Results

Overall recurrent stroke risk at 1 year was 6.7%/y, divided between 5.6%/y for recurrent ischemic and 0.5%/y for recurrent hemorrhagic strokes. There was a stronger association between WMH volume and recurrent hemorrhagic stroke by quartile (hazard ratio [HR] 7.32, 14.12, and 33.52, respectively) than for ischemic recurrence (HR 1.03, 1.37, and 1.61, respectively), but the absolute incidence of ischemic recurrence by quartile was higher (3.8%/y, 4.5%/y, 6.3%/y, and 8.2%/y by quartiles) vs hemorrhagic recurrence (0.1%/y, 0.4%/y, 0.6%/y, and 1.3%/y). All-cause mortality (10.5%) showed a marked association with WMH volume (HR 1.06, 1.46, and 1.60), but this was attributable to nonvascular rather than vascular causes.

Conclusions

There is an association between WMH volume load and stroke recurrence, and this association is stronger for hemorrhagic than for ischemic stroke, although the absolute risk of ischemic recurrence remains higher. These data should be helpful to practitioners seeking to find the optimal preventive/treatment regimen for poststroke patients and to individualize risk-benefit ratios.

Gamma probe-guided confirmation of balloon placement in endovascular procedures

BACKGROUND

Gamma probes can provide real-time information on lesion location and allow radioguided surgery in many diseases. The purpose of this study was to determine whether a gamma probe could be used to confirm balloon location in resuscitative endovascular balloon occlusion of the aorta and to determine the ease-of-use of the gamma probe localization method using human vasculature phantom and large animal.

METHODS

This investigation comprised a proof-of-concept study using human vasculature phantom and feasibility study using large animal. An assistant and two general surgeons with no prior experience in handling a gamma probe participated in both studies. A gamma probe was used by each surgeon to explore the location of a catheter balloon filled with 8 mL of normal saline containing 37 MBq of Technetium. The differences between predicted and actual balloon locations and the times taken to perform the trials were recorded. Balloon locations were confirmed by planar gamma camera images. The results were analyzed and compared according to the operators and experiments.

RESULTS

Overall sensitivity and specificity for the localization of the catheter balloon were 100% and 91% in phantom study, respectively, and 100% and 100% in animal study, respectively. The performance of the two operators for exploring the balloon location was similar in both the phantom and the animal studies. The mean time taken to explore the balloon locations with the aid of the gamma probe was only 2.36 minutes in phantom study and 2.65 minutes in the animal study.

CONCLUSION

The gamma probe method was accurate and rapid for confirming balloon location. We suggest that the gamma probe has potential for confirming balloon placement in endovascular procedures without the need for fluoroscopy.