Project description:IntroductionCardioembolic (CE) risks is usually considered as the main mechanism of ischemic stroke in non-valvular atrial fibrillation (NVAF) patients. However, a substantial number of ischemic strokes in NVAF patients are related to non-CE mechanisms. The aim of this study was to investigate the non-CE risk factors in ischemic stroke patients had NVAF.MethodsWe included 401 patients (65.6% male, 68.6 ± 9.6 years old) who had been hospitalized due to ischemic stroke and had a known or newly diagnosed NVAF. The CE (intracardiac thrombus, dense spontaneous echo contrast, or low left atrial appendage flow velocity) and non-CE (complex aortic plaque, significant carotid stenosis, or intracranial arterial stenosis) risk factors were investigated at the time of the index stroke.ResultsThe number of CE and non-CE risk factors increased with increasing CHA2DS2-VASc scores (p for trends < 0.001). The presence of CE risk factors was independently associated with persistent atrial fibrillation (p < 0.001), body mass index (p = 0.003), heart failure (p = 0.003), and left atrial volume index (p < 0.001). In contrast, the presence of non-CE risk factors was independently associated with age (p < 0.001), hypertension (p = 0.049), diabetes (p = 0.030), and coronary artery calcium score (CACS; p < 0.001). CACS had the added value in predicting non-CE risk factors of ischemic stroke regardless of the CHA2DS2-VASc risk category (p < 0.001).ConclusionNon-CE risk factors in ischemic stroke patients with NVAF are associated with high CHA2DS2-VASc score and CACS. Atherosclerotic non-CE risk factors should be considered as potential mechanisms of stroke even in patients with AF-associated ischemic stroke.
Project description:Background and Purpose- Classification of stroke as cardioembolic in etiology can be challenging, particularly since the predominant cause, atrial fibrillation (AF), may not be present at the time of stroke. Efficient tools that discriminate cardioembolic from noncardioembolic strokes may improve care as anticoagulation is frequently indicated after cardioembolism. We sought to assess and quantify the discriminative power of AF risk as a classifier for cardioembolism in a real-world population of patients with acute ischemic stroke. Methods- We performed a cross-sectional analysis of a multi-institutional sample of patients with acute ischemic stroke. We systematically adjudicated stroke subtype and examined associations between AF risk using CHA2DS2-VASc, Cohorts for Heart and Aging Research in Genomic Epidemiology-AF score, and the recently developed Electronic Health Record-Based AF score, and cardioembolic stroke using logistic regression. We compared the ability of AF risk to discriminate cardioembolism by calculating C statistics and sensitivity/specificity cutoffs for cardioembolic stroke. Results- Of 1431 individuals with ischemic stroke (age, 65±15; 40% women), 323 (22.6%) had cardioembolism. AF risk was significantly associated with cardioembolism (CHA2DS2-VASc: odds ratio [OR] per SD, 1.69 [95% CI, 1.49-1.93]; Cohorts for Heart and Aging Research in Genomic Epidemiology-AF score: OR, 2.22 [95% CI, 1.90-2.60]; electronic Health Record-Based AF: OR, 2.55 [95% CI, 2.16-3.04]). Discrimination was greater for Cohorts for Heart and Aging Research in Genomic Epidemiology-AF score (C index, 0.695 [95% CI, 0.663-0.726]) and Electronic Health Record-Based AF score (0.713 [95% CI, 0.681-0.744]) versus CHA2DS2-VASc (C index, 0.651 [95% CI, 0.619-0.683]). Examination of AF scores across a range of thresholds indicated that AF risk may facilitate identification of individuals at low likelihood of cardioembolism (eg, negative likelihood ratios for Electronic Health Record-Based AF score ranged 0.31-0.10 at sensitivity thresholds 0.90-0.99). Conclusions- AF risk scores associate with cardioembolic stroke and exhibit moderate discrimination. Utilization of AF risk scores at the time of stroke may be most useful for identifying individuals at low probability of cardioembolism. Future analyses are warranted to assess whether stroke subtype classification can be enhanced to improve outcomes in undifferentiated stroke.
Project description:BackgroundPrimary aldosteronism (PA) is the most common cause of secondary hypertension, and patients are at an increased risk of atrial fibrillation (AF) and stroke. We assessed the prevalence of PA in patients with recent stroke.MethodsWe recruited 300 patients admitted to an acute stroke unit with diagnosis of cerebrovascular accident (haemorrhagic/ischaemic) or transient ischaemic attack. Three months post-stroke, plasma renin and aldosterone were measured. Patients with an elevated aldosterone-renin ratio proceeded to the confirmatory saline loading test.ResultsTwenty-six of 192 (14%) patients had an elevated aldosterone-renin ratio. Three of 14 patients who proceeded to saline loading were confirmed with PA (post-saline aldosterone >138 pmol/l). Another three patients were classified as confirmed/likely PA based on the markedly elevated aldosterone-renin ratio and clinical characteristics. The overall prevalence of PA amongst stroke patients with hypertension was 4.0% (95% confidence interval (CI): 0.9%-7.1%). Prevalence of PA was higher amongst patients with cardioembolic stroke, 11% (95% CI: 1.3%-33%), resistant hypertension, 11% (95% CI: 0.3%-48%), and hypertension and AF, 30% (95%CI: 6.7%-65%). If only young patients or those with hypokalaemia were screened for PA, half of our patients with PA would not have been diagnosed. Our decision tree identified that stroke patients with AF and diastolic blood pressure ≥83mmHg were most likely to have PA.ConclusionWe found that amongst hypertensive patients with stroke, PA was more prevalent in those with AF, or cardioembolic stroke. Screening for PA should be considered for all patients with stroke.
Project description:ObjectiveTo investigate the long-term prognostic implications of transient new-onset atrial fibrillation (AF) in patients with acute myocardial infarction (AMI).DesignRetrospective observational study.SettingSingle tertiary centre.ParticipantsThis study included 2523 patients who presented with AMI from 3 June 2003 to 24 February 2015, after the exclusion of those with prior AF or in-hospital death.Outcome measuresPatients were divided into three groups according to the occurrence and type of new-onset AF: (1) sinus rhythm (SR) group; (2) paroxysmal AF (PaAF: AF converted to SR prior to discharge) group and (3) persistent AF (PeAF: AF persisted during the hospitalisation) group. Post-discharge all-cause mortality and stroke incidences were compared between the groups.ResultsNew-onset AF was observed in 271 patients (10.7%; PaAF: 230, PeAF: 41). The median follow-up period was 7.2 years (IQR: 5.2-9.4). The incidence of all-cause death and stroke was highest in the PeAF group, followed by the PaAF and SR groups (all-cause mortality: 48.8% vs 26.5% vs 14.7%, p<0.001; stroke 22.0% vs 8.3% vs 4.4%, p<0.001). In the multivariable analysis, PaAF and PeAF were associated with an increased risk of stroke (PaAF, HR: 1.972, 95% CI: 1.162-3.346; PeAF, HR: 5.160, CI: 2.242-11.873) compared with SR. The PaAF group showed a higher incidence of post-discharge AF than the SR group (29.1% vs 4.2%, p<0.001).ConclusionsNew-onset AF following AMI is associated with poor long-term outcomes. Even when AF episodes are brief and are converted to SR, new-onset AF remains associated with an increased risk of recurrent AF and stroke.
Project description:Acute myocardial infarction is a well know precipitant of atrial fibrillation, but it is also becoming increasingly recognised that atrial fibrillation is a direct and indirect cause of acute myocardial infarction. Current guidelines do not recommend anticoagulation therapy in patients undergoing cardiac surgery who have a brief episode of atrial fibrillation lasting less than 48 h. However, recommendations for the management of atrial fibrillation following non-cardiac surgery are less clear. We describe the case of a 70-year-old man undergoing non-cardiac surgery, who developed a short episode of perioperative atrial fibrillation and later presented with thromboembolic acute myocardial infarction due to a thrombotic occlusion of the right coronary artery.
Project description:BACKGROUND:Large-scale clinical trials have analyzed risk factors for any ischemic stroke in patients with atrial fibrillation (AF). However, the risk factors for cardioembolic stroke (CES), specifically, have not been reported. To clarify the risk factors for CES and clinically significant cardioembolic infarction, we examined the incidence of CES and larger infarct volume (IV) (> 30 mL) CES, employing the Fushimi AF Registry, a community-based prospective cohort of AF patients in the Fushimi ward, Kyoto, Japan. METHODS:A total of 4,182 Fushimi AF patients were enrolled from March 2011 to December 2014. The risk factors for CES were evaluated using multivariate analysis. RESULTS:Of 4,182 patients enrolled, 3,749 patients were observed for ?1 year. During the follow-up period (mean duration, 979 ± 7.7 days), 91/3,749 patients experienced a CES (2.43%). Significant risk factors associated with CES were older age (odds ratio [OR], 1.31; 95% confidence interval [CI], 1.01-1.72; p = 0.046), low body weight (OR, 1.30; 95% CI, 1.03-1.65; p = 0.033), sustained AF (OR, 1.67; 95% CI, 1.05-2.71; p = 0.034), and previous stroke or transient ischemic attack (TIA) (OR, 1.94; 95% CI, 1.22-3.06; p = 0.004). Predictors of a large IV were chronic kidney disease (CKD) (OR, 2.08; 95% CI, 1.09-4.05; p = 0.027) and previous stroke/TIA (OR, 2.27; 95% CI, 1.19-4.24; p = 0.011). CONCLUSIONS:In this population-based cohort of Japanese patients with AF, in addition to previous stroke/TIA and older age, sustained AF and low body weight emerged as risk factors for CES, as opposed to any stroke, which may have a different risk profile. Patients with CKD or previous stroke/TIA who developed cardioembolic infarction exhibited more advanced severity. There is a need for direct oral anticoagulants that can be used safely in patients with comorbid AF and CKD.
Project description:Patients with a cardioembolic stroke (CES) have worse outcomes than stroke patients with other causes of stroke. Among patients with CES, atrial fibrillation (AF) is a common comorbidity. Mounting data indicate that AF may be related to stroke pathogenesis beyond acute cerebral thromboembolism. We sought to determine whether AF represents an independent risk factor for stroke severity and outcome among patients with CES.We retrospectively analyzed patients with acute hemispheric CES included in an academic medical center's stroke registry. CES was determined using the Causative Classification System of ischemic stroke. Multivariable logistic regression was used to determine whether AF was associated with 90-day outcome functional status.Our cohort included 140 patients. Of these, 52 had prevalent AF and 28 had incident AF diagnosed during their index hospitalization or within 90 days of hospital discharge. After adjustment for potential confounders or mediators, any AF (odds ratio, 2.51; 95% confidence interval, 1.03-6.33; P=0.049), infarct volume (odds ratio, 1.03; 95% confidence interval, 1.01-1.06; P=0.005), preadmission modified Rankin Scale score (odds ratio, 2.58; 95% confidence interval, 1.66-4.01; P<0.001), and admission National Institutes of Health Stroke Scale score (odds ratio, 1.17; 95% confidence interval, 1.08-1.28; P<0.001) remained associated with an unfavorable 90-day outcome (modified Rankin Scale score, 2-6).AF is associated with an unfavorable 90-day outcome among patients with a CES independent of established risk factors and initial stroke severity. This suggests that AF-specific mechanisms affect CES severity and functional status after CES. If confirmed in future studies, further investigation into the underlying pathophysiological mechanisms may provide novel avenues to AF detection and treatment.
Project description:Background It remains controversial whether long-term clinical impact of newly diagnosed atrial fibrillation (AF) in the acute phase of acute myocardial infarction (AMI) is different from that of prior AF diagnosed before the onset of AMI. Methods and Results The current study population from the CREDO-Kyoto AMI (Coronary Revascularization Demonstrating Outcome Study in Kyoto Acute Myocardial Infarction) Registry Wave-2 consisted of 6228 patients with AMI who underwent percutaneous coronary intervention. The baseline characteristics and long-term clinical outcomes were compared according to AF status (newly diagnosed AF: N=489 [7.9%], prior AF: N=589 [9.5%], and no AF: N=5150 [82.7%]). Median follow-up duration was 5.5 years. Patients with newly diagnosed AF and prior AF had similar baseline characteristics with higher risk profile than those with no AF including older age and more comorbidities. The cumulative 5-year incidence of all-cause death was higher in newly diagnosed AF and prior AF than no AF (38.8%, 40.7%, and 18.7%, P<0.001). The adjusted hazard ratios (HRs) for mortality of newly diagnosed AF and prior AF relative to no AF remained significant with similar magnitude (HR, 1.31; 95% CI, 1.12-1.54; P<0.001, and HR, 1.32; 95% CI, 1.14-1.52; P<0.001, respectively). The cumulative 5-year incidence of stroke decreased in the order of newly diagnosed AF, prior AF and no AF (15.5%, 12.9%, and 6.3%, respectively, P<0.001). The higher adjusted HRs of both newly diagnosed AF and prior AF relative to no AF were significant for stroke, with a greater risk of newly diagnosed AF than that of prior AF (HR, 2.05; 95% CI, 1.56-2.69; P<0.001, and HR, 1.33; 95% CI, 1.00-1.78; P=0.048, respectively). The higher stroke risk of newly diagnosed AF compared with prior AF was largely driven by the greater risk within 30 days. The higher adjusted HRs of newly diagnosed AF and prior AF relative to no AF were significant for heart failure hospitalization (HR, 1.73; 95% CI, 1.35-2.22; P<0.001, and HR, 2.23; 95% CI, 1.82-2.74; P<0.001, respectively) and major bleeding (HR, 1.46; 95% CI, 1.23-1.73; P<0.001, and HR, 1.36; 95% CI, 1.15-1.60; P<0.001, respectively). Conclusions Newly diagnosed AF in AMI had risks for mortality, heart failure hospitalization, and major bleeding higher than no AF, and comparable to prior AF. The risk of newly diagnosed AF for stroke might be higher than that of prior AF.
Project description:ObjectiveTo determine whether altered metabolic profiles represent a link between atrial dysfunction and cardioembolic (CE) stroke, and thus whether underlying dysfunctional atrial substrate may contribute to thromboembolism risk in CE stroke.MethodsA total of 144 metabolites were measured using liquid chromatography-tandem mass spectrometry in plasma samples collected within 9 hours of stroke onset in 367 acute stroke patients. Stroke subtype was assigned using the Causative Classification of Stroke System, and CE stroke (n = 181) was compared to non-CE stroke (n = 186). Markers of left atrial dysfunction included abnormal atrial function (P-wave terminal force in lead V1, PTFV1 >4,000 μV·ms), left atrial enlargement on echocardiography, and frank atrial fibrillation on ECG. Stroke recurrence risk was assessed using CHADS2 and CHA2DS2-VASc scores. Associations between metabolites and CE stroke, atrial dysfunction, and stroke recurrence risk were evaluated using logistic regression models.ResultsThree tricarboxylic acid metabolites-succinate (odds ratio [OR] 1.71, 95% confidence interval [CI] 1.36-2.15, p = 1.37 × 10-6), α-ketoglutarate (OR 1.62, 95% CI 1.29-2.04, p = 1.62 × 10-5), and malate (OR 1.58, 95% CI 1.26-1.97, p = 2.57 × 10-5)-were associated with CE stroke. Succinate (OR 1.36, 95% CI 1.31-1.98, p = 1.22 × 10-6), α-ketoglutarate (OR 2.14, 95% CI 1.60-2.87, p = 2.08 × 10-8), and malate (OR 2.02, 95% CI 1.53-2.66, p = 1.60 × 10-7) were among metabolites also associated with subclinical atrial dysfunction. Of these, succinate was also associated with left atrial enlargement (OR 1.54, 95% CI 1.23-1.94, p = 1.06 × 10-4) and stroke recurrence based on dichotomized CHADS2 (OR 2.63, 95% CI 1.68-4.13, p = 3.00 × 10-6) and CHA2DS2-VASc (OR 2.43, 95% CI 1.60-3.68, p = 4.25 × 10-6) scores.ConclusionsMetabolite profiling identified changes in succinate associated with CE stroke, atrial dysfunction, and stroke recurrence, revealing a putative underlying link between CE stroke and energy metabolism.
Project description:ObjectiveCerebral microbleeds (CMBs) are a magnetic resonance imaging (MRI) marker for cerebral small vessel disease. Existing CMBs and those that newly develop are associated with the risks of stroke incidence and recurrence. The purpose of the present study was to investigate the association of oral anticoagulant (OAC) use and the development of new CMBs in cardioembolic stroke patients with atrial fibrillation.Subjects and methodsWe prospectively followed cardioembolic stroke patients with atrial fibrillation who had been hospitalized in the stroke center of our hospital, had been prescribed anticoagulants at discharge, and underwent repeated brain MRI with an interval of at least one year from the baseline MRI. Assessing the presence, number and location of CMBs using T2*-weighted gradient-recalled echo MRI, we used logistic regression models to investigate the associations between OAC use and the incidence of new CMBs. We also examined associations of subsequent stroke with OACs and CMBs during the follow-up.ResultsA total of 81 patients, consisting of 45 patients receiving direct oral anticoagulants (DOACs) and 36 patients receiving warfarin (WF), were analyzed in the present study. Baseline CMBs were observed in 19/81 patients (23.5%) and new CMBs in 18/81 patients (22.2%) on follow-up MRI (median interval, 34 months). Of the 31 new CMBs, 25 (80.6%) developed in the lobar location and 6 (19.4%) in the deep or infratentorial location. New CMBs occurred in 4 patients (10.0%) taking DOACs alone, in 10 patients (35.7%) taking WF alone, in 3 patients (37.5%) taking WF plus antiplatelet agents and in 1 patient (20.0%) taking DOAC plus antiplatelet agent. Regarding location, the new CMBs were the lobar type in 7 of the 10 patients taking WF alone, as well as in 3 of the 4 patients taking DOACs alone. In multivariate analysis, the presence of CMBs at baseline and WF use (vs. DOAC use) were associated with new CMBs (CMB presence at baseline: OR 4.16, 95% CI 1.19-14.44; WF use: OR 3.38, 95% CI 1.02-11.42). The presence of ≥ 2 CMBs at baseline was related to a higher risk of subsequent stroke (OR 7.25, 95% CI 1.01-52.35, P = 0.048).ConclusionOur findings suggest that DOAC compared with WF use at discharge is associated with a lower incidence of new CMBs in cardioembolic stroke patients with atrial fibrillation. Further prospective studies in the clinical setting are needed to confirm our exploratory data.