Tobias Bobinger

Serious Cardiac Arrhythmias After Stroke Incidence, Time Course, and Predictors—A Systematic, Prospective Analysis

Background and Purpose— Patients with acute cerebrovascular events are susceptible to serious cardiac arrhythmias, but data on the time course and the determinants of their onset are scarce. Methods— The prospective Stroke-Arrhythmia-Monitoring-Database (SAMBA) assessed cardiac arrhythmias with need for urgent evaluation and treatment in 501 acute neurovascular patients during the first 72 hours after admission to a monitored stroke unit. Arrhythmias were systematically detected by structured processing of telemetric data. Time of arrhythmia onset and predisposing factors were investigated. Results— Significant cardiac arrhythmias occurred in 25.1% of all patients. Incidence was highest during the first 24 hours after admission. Serious arrhythmic tachycardia (ventricular or supraventricular >130 beats/min) was more frequent than bradycardic arrhythmia (sinus-node dysfunction, bradyarrhythmia, or atrioventricular block °II and °III). Arrhythmias were independently associated with higher age and severer neurological deficits as measured by the National Institutes of Health Stroke Scale on admission. Conclusions— The risk for significant cardiac arrhythmia after an acute cerebrovascular event is highest during the first 24 hours of care and declines with time during the first 3 days. Along with established vascular risk factors, the National Institutes of Health Stroke Scale may be considered for a stratified allocation of monitoring capabilities. Clinical Trial Registration— URL: www.clinicaltrials.gov. Unique identifier: NCT01177748.

Hyponatremia Is an Independent Predictor of In-Hospital Mortality in Spontaneous Intracerebral Hemorrhage

Background and Purpose— Hyponatremia is the most frequent electrolyte disturbance in critical care. Across various disciplines, hyponatremia is associated with increased mortality and longer hospital stay, yet in intracerebral hemorrhage (ICH) no data are available. This the first study that investigated the prevalence and clinical associations of hyponatremia in patients with ICH. Methods— This observational study included all consecutive spontaneous ICH patients (n=464) admitted during a 5-year period to the Department of Neurology. Patient characteristics, in-hospital measures, mortality, and functional outcome (90 days and 1 year) were analyzed to determine the effects of hyponatremia (Na <135 mEq/L). Multivariable regression analyses were calculated for factors associated with hyponatremia and predictors of in-hospital mortality. Results— The prevalence of hyponatremia on hospital admission was 15.6% (n=66). Normonatremia was achieved and maintained in almost all hyponatremia patients <48 hours. In-hospital mortality was roughly doubled in hyponatremia compared with nonhyponatremia patients (40.9%; n=27 versus 21.1%; n=75), translating into a 2.5-fold increased odds ratio (P<0.001). Multivariable analyses identified hyponatremia as an independent predictor of in-hospital mortality (odds ratio, 2.2; 95% confidence interval, 1.05–4.62; P=0.037). Within 90 days after ICH, hyponatremia patients surviving hospital stay were also at greater risk of death (odds ratio, 4.8; 95% confidence interval, 2.1–10.6; P<0.001); thereafter, mortality rates were similar. Conclusions— Hyponatremia was identified as an independent predictor of in-hospital mortality with a fairly high prevalence in spontaneous ICH patients. The presence of hyponatremia at hospital admission is related to an increased short-term mortality in patients surviving acute care, possibly reflecting a preexisting condition that is linked to worse outcome due to greater comorbidity. Correction of hyponatremia does not seem to compensate its influence on mortality, which strongly warrants future research.

Neutrophil-to-Lymphocyte Ratio Is an Independent Predictor for In-Hospital Mortality in Spontaneous Intracerebral Hemorrhage

Background and Purpose: Stroke-associated immunosuppression and inflammation are increasingly recognized as factors that trigger infections and thus, potentially influence the outcome after stroke. Several studies demonstrated that elevated neutrophil-to-lymphocyte ratio (NLR) is a significant predictor of adverse outcomes in patients with ischemic stroke. However, little is known about the impact of NLR on short-term mortality in intracerebral hemorrhage (ICH). Methods: This observational study included 855 consecutive ICH-patients. Patient demographics, clinical, laboratory, and in-hospital measures as well as neuroradiological data were retrieved from institutional databases. Functional 3-months-outcome was assessed and categorized as favorable (modified Rankin Scale [mRS] 0-3) and unfavorable (mRS 4-6). We (i) studied the natural course of NLR in ICH, (ii) analyzed parameters associated with NLR on admission (NLROA), and (iii) evaluated the clinical impact of NLR on mortality and functional outcome. Results: The median NLROA of the entire cohort was 4.66 and it remained stable during the entire hospital stay. Patients with NLR ≥4.66 showed significant associations with poorer neurological status (National Institute of Health Stroke Scale [NIHSS] 18 [9-32] vs. 10 [4-21]; p < 0.001), larger hematoma volume on admission (17.6 [6.9-47.7] vs. 10.6 [3.8-31.7] mL; p = 0.001), and more frequently unfavorable outcome (mRS 4-6 at 3 months: 317/427 [74.2%] vs. 275/428 [64.3%]; p = 0.002). Patients with an NLR under the 25th percentile (NLR <2.606) - compared to patients with NLR >2.606 - presented with a better clinical status (NIHSS 12 [5-21] vs. 15 [6-28]; p = 0.005), lower hematoma volumes on admission (10.6 [3.6-30.1] vs. 15.1 [5.7-42.3] mL; p = 0.004) and showed a better functional outcome (3 months mRS 0-3: 82/214 [38.3%] vs. 185/641 [28.9%]; p = 0.009). Patients associated with high NLR (≥8.508 = above 75th-percentile) showed the worst neurological status on admission (NIHSS 21 [12-32] vs. 12 [5-23]; p < 0.001), larger hematoma volumes (21.0 [8.6-48.8] vs. 12.2 [4.1-34.9] mL; p < 0.001), and higher proportions of unfavorable functional outcome at 3 months (mRS 4-6: 173/214 vs. 418/641; p < 0.001). Further, NLR was linked to more frequently occurring infectious complications (pneumonia 107/214 vs. 240/641; p = 0.001, sepsis: 78/214 vs. 116/641; p < 0.001), and increased c-reactive-protein levels on admission (p < 0.001; R2 = 0.064). Adjusting for the above-mentioned baseline confounders, multivariable logistic analyses revealed independent associations of NLROA with in-hospital mortality (OR 0.967, 95% CI 0.939-0.997; p = 0.029). Conclusions: NLR represents an independent parameter associated with increased mortality in ICH patients. Stroke physicians should focus intensely on patients with increased NLR, as these patients appear to represent a population at risk for infectious complications and increased short-mortality. Whether these patients with elevated NLR may benefit from a close monitoring and specially designed therapies should be investigated in future studies.

Lymphocytopenia Is an Independent Predictor of Unfavorable Functional Outcome in Spontaneous Intracerebral Hemorrhage

Background and Purpose— Stroke-associated immunosuppression is an increasingly recognized factor triggering infections and thus potentially influencing outcome after stroke. Specifically, lymphocytopenia after intracerebral hemorrhage (ICH) has only been addressed in small-sized retrospective studies of mixed intracranial bleedings. This cohort study investigated the natural course of lymphocytopenia, parameters associated with lymphocytopenia on admission (LOA) and during stay, and evaluated the clinical impact of lymphocytopenia in solely ICH patients. Methods— This observational study included 855 consecutive patients with ICH. Patient demographics, clinical and neuroradiological data as well as laboratory and in-hospital measures were retrieved from institutional prospective databases. Functional 3-month outcome was assessed by mailed questionnaires. Lymphocytopenia was defined as <1.0 (109/L) and was correlated with patient’s characteristics and outcome. Results— Prevalence of LOA was 27.3%. Patients with LOA showed significant associations with poorer neurological status (18 [10–32] versus 13 [5–24]; P<0.001), larger hematoma volume (18.5 [6.2–46.2] versus 12.8 [4.4–37.8]; P=0.006), and unfavorable outcome (74.7% versus 63.3%; P=0.0018). Natural course of lymphocyte count during hospital stay revealed a lymphocyte nadir of 1.1 (0.80–1.53 [109/L]) at day 5. Focusing on patients with day-5-lymphocytopenia, compared with patients with LOA, revealed increased rates of infections (63 [71.6] versus 113 [48.5]; P<0.001) and poorer functional outcome at 3 months (76 [86.4] versus 175 [75.1); P=0.029). Adjusting for baseline confounders, multivariable logistic and receiver operating characteristics analyses documented independent associations of day-5-lymphocytopenia with unfavorable outcome (day-5-lymphocytopenia: odds ratio, 2.017 [95% confidence interval, 1.029–3.955], P=0.041; LOA: odds ratio, 1.391 [0.795–2.432], P=0.248; receiver operating characteristics: day-5-lymphocytopenia: area under the curve=0.673, P<0.0001, Youden’s index=0.290; LOA: area under the curve=0.513, P=0.676, Youden’s index=0.084), whereas receiver operating characteristics analyses revealed no association of age or hematoma volume with day-5-lymphocytopenia (age: area under the curve=0.540, P=0.198, Youden’s index=0.106; volume: area under the curve=0.550, P=0.0898, Youden’s index=0.1224). Conclusions— Lymphocytopenia is frequently present in patients with ICH and may represent an independent parameter associated with unfavorable functional outcome. Developing lymphocytopenia affected outcome even stronger than LOA, a finding that may open up new therapeutic avenues in specific subsets of patients with ICH.

Adherence to Oral Anticoagulation in Secondary Stroke Prevention—The First Year of Direct Oral Anticoagulants

BACKGROUND Patients with ischemic stroke caused by atrial fibrillation (AF) have a high risk of recurrence without adequate secondary prevention with oral anticoagulation (OAC). We investigated adherence to OAC in the first year after introduction of direct oral anticoagulants. METHODS In 284 appropriate patients, the rate of anticoagulation (AC) at discharge, adherence at 90 days and 1 year, changes between substances, and predictors for adherence to AC were analyzed. Functional outcome was assessed using the modified Rankin Scale score. RESULTS AC was initiated in 70.3% of survivors before discharge. In these patients, only 8.6% and 9.9% discontinued AC after 90 days and 1 year, respectively. In 22.1%, AC was recommended but not started before discharge. Only 53.2% of them received AC at 90 days, increasing to 67.5% at 1 year. A total of 7.6% of patients were deemed unsuitable for AC, none of them subsequently received AC. Overall, 85.4% of patients suitable for AC were treated at 1-year follow-up. No independent predictors for withholding AC were identified. Switching of medication occurred in only a minority of patients within the first year. CONCLUSIONS AC is feasible in more than 90% patients with acute ischemic stroke and AF. When initiated during the acute hospital stay, AC is discontinued in only a minority of patients. However, if AC is recommended but not started during initial hospitalization the rate of AC treatment at 90 days and 1 year is much lower. Therefore, AC should be initiated within the acute hospital stay whenever possible.

Severity assessment in maximally treated ICH patients: The max-ICH score.

Objective: As common prognostication models in intracerebral hemorrhage (ICH) are developed variably including patients with early (<24 hours) care limitations (ECL), we investigated its interaction with prognostication in maximally treated patients and sought to provide a new unbiased severity assessment tool. Methods: This observational cohort study analyzed consecutive ICH patients (n = 583) from a prospective registry over 5 years. We characterized the influence of ECL on overall outcome by propensity score matching and on conventional prognostication using receiver operating characteristic analyses. We established the max-ICH score based on independent predictors of 12-month functional outcome in maximally treated patients and compared it to existing models. Results: Prevalence of ECL was 19.2% (n = 112/583) and all of these patients died. Yet propensity score matching displayed that 50.7% (n = 35/69) theoretically could have survived, with 18.8% (n = 13/69) possibly reaching favorable outcome (modified Rankin Scale score 0–3). Conventional prognostication seemed to be confounded by ECL, documented by a decreased predictive validity (area under the curve [AUC] 0.67, confidence interval [CI] 0.61–0.73 vs AUC 0.80, CI 0.76–0.83; p < 0.01), overestimating poor outcome (mortality by 44.8%, unfavorable outcome by 10.1%) in maximally treated patients. In these patients, the novel max-ICH score (0–10) integrates strength-adjusted predictors, i.e., NIH Stroke Scale score, age, intraventricular hemorrhage, anticoagulation, and ICH volume (lobar and nonlobar), demonstrating improved predictive accuracy for functional outcome (12 months: AUC 0.81, CI 0.77–0.85; p < 0.01). The max-ICH score may more accurately delineate potentials of aggressive care, showing favorable outcome in 45.4% (n = 214/471) and a long-term mortality rate of only 30.1% (n = 142/471). Conclusions: Care limitations significantly influenced the validity of common prognostication models resulting in overestimation of poor outcome. The max-ICH score demonstrated increased predictive validity with minimized confounding by care limitations, making it a useful tool for severity assessment in ICH patients.

Early Initiation of Anticoagulation with Direct Oral Anticoagulants in Patients after Transient Ischemic Attack or Ischemic Stroke

BACKGROUND Direct oral anticoagulants (DOACs) are increasingly used for secondary prevention of cardioembolic stroke. While DOACs are associated with a long-term reduced risk of intracranial hemorrhage compared to vitamin K antagonists, pivotal trials avoided the very early period after stroke and few data exist on early initiation of DOAC therapy post stroke. METHODS We retrospectively analyzed data from our prospective database of all consecutive transient ischemic attack (TIA) or ischemic stroke patients with atrial fibrillation treated with DOACs during hospital stay. As per our institutional treatment algorithm for patients with cardioembolic ischemia DOACs are started immediately in TIA and minor stroke (group 1), within days 3-5 in patients with infarcts affecting one third or less of the middle cerebral artery, the anterior cerebral artery, or the posterior cerebral artery territories (group 2) as well as in infratentorial stroke (group 3) and after 1-2 weeks in patients with large infarcts (>⅓MCA territory, group 4). We investigated baseline characteristics, time to initiation of DOAC therapy after symptom onset, and hemorrhagic complications. RESULTS In 243 included patients, administration of DOAC was initiated 40.5 hours (interquartile range [IQR] 23.0-65.5) after stroke onset in group 1 (n = 41) and after 76.7 hours (IQR 48.0-134.0), 108.4 hours (IQR 67.3-176.4), and 161.8 hours (IQR 153.9-593.8) in groups 2-4 (n = 170, 28, and 4), respectively. Two cases of asymptomatic intracranial hemorrhage (.8%) and 1 case of symptomatic intracranial hemorrhage (.4%) were observed, both in group 2. CONCLUSIONS No severe safety issues were observed in early initiation of DOACs for secondary prevention after acute stroke in our in-patient cohort.

Lost memories can break your heart: a case report of transient global amnesia followed by takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TC), also called apical ballooning syndrome, is characterized by an acute, transient systolic dysfunction of the apical and mid segments of the left ventricle. Recently, there have been reports showing an association with neurologic disorders including myasthenic crisis [1], Guillain–Barre–Strohl syndrome [2], seizures [3] and ischemic stroke [4]. In this article, we present the case of a woman, who suffered from a second episode of transient global amnesia (TGA) followed by TC. A 62-year-old woman presented to our emergency room with typical symptoms of TGA, thereby asking repetitive questions regarding the situation and events over the last hours. Symptom onset had occurred during the visit to a public swimming pool. Apart from isolated global amnesia, the neurologic examination was normal; a CT-scan of the brain was unremarkable. An EEG was done and ruled out an epileptic cause of the syndrome. Extracranial and transcranial vascular ultrasound did not reveal any pathologic findings. The patient had a past medical history of hypothyroidism with need for oral substitution and a previous episode of TGA 2 years before. Four hours after the patient was admitted to our intermediate care unit, she developed acute chest pain and dyspnoea. The troponin I level was elevated at 4.64 ng/ml. Acute coronary syndrome was suspected and an emergency coronary angiography was performed, which did not show relevant coronary artery disease. Ventriculography revealed severe hypokinesis of mid and apical segments of the left ventricle with the characteristic shape of takotsubo cardiomyopathy (Figs. 1, 2; supplemental ultrasound video Movie—TakoTsubo.mpg). The patient was stable during the further course and showed full recovery from all amnestic deficits within 18 h. On follow-up echocardiography, a complete normalization of cardiac function with normal left ventricular diameter, no wall motion abnormalities and a normal ejection fraction were found. The patient was then discharged in a good state of health. Transient global amnesia was first described in 1956 by Guyotat and Courjon as an acute cognitive disorder with predominantly anterograde amnesia for up to 24 h [5]. Most episodes occur at the age of 50–80 years, do not show an association with vascular risk factors and are frequently precipitated by emotional stress, physical effort, water Electronic supplementary material The online version of this article (doi:10.1007/s00392-013-0590-1) contains supplementary material, which is available to authorized users.

Reliability and Limitations of Automated Arrhythmia Detection in Telemetric Monitoring After Stroke

Background and Purpose— Guidelines recommend continuous ECG monitoring in patients with cerebrovascular events. Studies on intensive care units (ICU) demonstrated high sensitivity but high rates of false alarms of monitoring systems resulting in desensitization of medical personnel potentially endangering patient safety. Data on patients with acute stroke are lacking. Methods— One-hundred fifty-one consecutive patients with acute cerebrovascular events were prospectively included. Automatically identified arrhythmia events were analyzed by manual ECG analysis. Muting of alarms was registered. Sensitivity was evaluated by beat-to-beat analysis of the entire recorded ECG data in a subset of patients. Ethics approval was obtained by University of Erlangen-Nuremberg. Results— A total of 4809.5 hours of ECG registration and 22 509 alarms were analyzed. The automated detection algorithm missed no events but the overall rate of false alarms was 27.4%. Only 0.6% of all alarms indicated acute life-threatening events and 91.4% of these alarms were incorrect. Transient muting of acoustic alarms was observed in 20.5% patients. Conclusions— Continuous ECG monitoring using automated arrhythmia detection is highly sensitive in acute stroke. However, high rates of false alarms and alarms without direct therapeutic consequence cause desensitization of personnel. Therefore, acoustic alarms may be limited to life-threatening events but standardized manual evaluation of all alarms should complement automated systems to identify clinically relevant arrhythmias.

Impact of Heart Rate Dynamics on Mortality in the Early Phase after Ischemic Stroke: A Prospective Observational Trial

BACKGROUND Growing evidence suggests that the heart rate (HR) at rest is an independent predictor of cardiovascular mortality. In ischemic stroke, continuous monitoring of HR is the standard of care, but systematic data on its dynamics and prognostic value during the acute phase are limited. METHODS In this prospective observational study, HR was measured by continuous electrocardiographic monitoring on admission and during the first 72 hours of care among patients who were awake with ischemic stroke and survived until discharge. Functional outcome was assessed after 90 days. RESULTS Data from 702 consecutive patients were analyzed (median age, 73 years, 54% men). The time course of HR was initially characterized by a rapid decline during the first 12 hours after admission. Among patients who survived until day 90, this was followed by a continuous downward trend in HR, whereas death after discharge was associated with a secondary increase and a reversal point 12 hours after admission. After adjustment for established risk factors, this secondary increase during the acute period was an independent predictor of death (hazard ratio, 3.73; 95% confidence interval, 1.47-9.43; P = .005). CONCLUSIONS A secondary rise of HR during care for acute ischemic stroke is an early sign of fatality and may represent a surrogate for an unfavorable sympathetic disinhibition. Further research is warranted to clarify the role of targeted HR reduction after ischemic stroke (http://clinicaltrials.gov/, unique identifier NCT01858779).