Race and stroke in an atrial fibrillation inception cohort: Findings from the Penn Atrial Fibrillation Free study.

BACKGROUND: Stroke may be the initial manifestation of atrial fibrillation (AF). Limited studies, however, have evaluated racial differences in stroke before the diagnosis of AF. OBJECTIVE: We assessed racial differences in strokes that occurred before and after AF diagnosis in the Penn Atrial Fibrillation Free study. METHODS: The Penn Atrial Fibrillation Free study consists of 56,835 patients from the University of Pennsylvania Health System who were free of AF at the index visit. We developed an inception cohort of 3507 patients with incident AF and without any remote history of stroke. RESULTS: Among the AF inception cohort, there were 538 patients with ischemic strokes and 54 with hemorrhagic strokes. Nearly half (n = 254; 47%) of the ischemic strokes occurred within a 6-month period before the diagnosis of AF. Of these, the majority of strokes occurred either on the day of (n = 158) or within a 7-day period before (n = 30) the diagnosis of incident AF. The remaining 284 (53%) ischemic strokes occurred a median of 3.6 years (interquartile range 1.9-5.4 years) after AF diagnosis. Compared with whites, blacks had an independently higher risk of having an ischemic stroke either before (adjusted odds ratio 1.37; 95% confidence interval 1.03-1.81) or after (adjusted hazard ratio 1.67; 95% confidence interval 1.30-2.14) AF diagnosis. CONCLUSION: In the population with incident AF, nearly half of the ischemic strokes occurred before the diagnosis of AF. Compared with whites, blacks had a higher risk of developing an ischemic stroke that persisted whether the stroke occurred in the period either before or after AF diagnosis.

Optimal QT interval correction formula in sinus tachycardia for identifying cardiovascular and mortality risk: Findings from the Penn Atrial Fibrillation Free study.

BACKGROUND: The QT interval measures cardiac repolarization, and prolongation is associated with adverse cardiovascular outcomes and death. The exponential Bazett correction formula overestimates the QT interval during tachycardia. OBJECTIVE: We evaluated 4 formulas of QT interval correction in individuals with sinus tachycardia for the identification of coronary artery disease, heart failure, and mortality. METHODS: The Penn Atrial Fibrillation Free study is a large cohort study of patients without atrial fibrillation. The present study examined 6723 Penn Atrial Fibrillation Free study patients without a history of heart failure and with baseline sinus rate ≥100 beats/min. Medical records were queried for index clinical parameters, incident cardiovascular events, and all-cause mortality. The QT interval was corrected by using Bazett (QT/RR(0.5)), Fridericia (QT/RR(0.33)), Framingham [QT + 0.154 * (1000 - RR)], and Hodges (QT + 105 * (1/RR - 1)) formulas. RESULTS: In 6723 patients with a median follow-up of 4.5 years (interquartile range 1.9-6.4 years), the annualized cardiovascular event rate was 2.3% and the annualized mortality rate was 2.2%. QT prolongation was diagnosed in 39% of the cohort using the Bazett formula, 6.2% using the Fridericia formula, 3.7% using the Framingham formula, and 8.7% using the Hodges formula. Only the Hodges formula was an independent risk marker for death across the range of QT values (highest tertile: hazard ratio 1.26; 95% confidence interval 1.03-1.55). CONCLUSION: Although all correction formulas demonstrated an association between QTc values and cardiovascular events, only the Hodges formula identified one-third of individuals with tachycardia that are at higher risk of all-cause mortality. Furthermore, the Bazett correction formula overestimates the number of patients with a prolonged QT interval and was not associated with mortality. Future work may validate these findings and result in changes to automated algorithms for QT interval assessment.

Prevalence and prognosis of traumatic intraventricular hemorrhage in patients with blunt head trauma.

BACKGROUND: Most studies of traumatic intraventricular hemorrhage (tIVH) contain fewer than 25 subjects and are retrospective in design, providing minimal information about the entity and its clinical significance. METHODS: We prospectively enrolled trauma patients from 18 centers in North America in the National Emergency X-Radiography Utilization Study (NEXUS) II if they received an emergent head computed tomography (CT) scan, as determined by the managing physician. Clinical data were collected at the time of enrollment and CT reports were compiled at least 1 month later. We calculated prevalence and demographics of tIVH from the 18 sites, while outcome data were gathered from medical records of patients with tIVH who were seen at any of six sites that participated in the follow-up portion of the study. We considered patients who underwent a neurosurgical intervention or who had a "poor outcome" (Glasgow Outcome Scale score of 1 to 3, death, persistent vegetative state, or severe disability) to have suffered a "combined outcome." RESULTS: Prevalence of tIVH among all trauma patients who received a head CT was 118 in 8,374, or 1.41%. Among tIVH patients, 70% had a "poor outcome" and 76% had a "combined outcome." A poor outcome appeared to be associated with an abnormal presenting Glasgow Coma Scale score and involvement of the third or fourth ventricle, whereas age appeared to be unrelated. Patients with tIVH and no major associated injury on CT tended to do well; only one patient with isolated tIVH had a poor outcome. CONCLUSIONS: Traumatic IVH is rare and is associated with poor outcomes that seem to be the consequence of associated injuries. Isolated tIVH patients who are clinically well appear to have a functional outcome; we were unable to identify a case of isolated tIVH, combined with a normal neurologic examination, resulting in a poor or combined outcome.

Defining "therapeutically inconsequential" head computed tomographic findings in patients with blunt head trauma.

STUDY OBJECTIVE: Many injuries detected by computed tomographic (CT) imaging of blunt head trauma patients are considered "therapeutically inconsequential." We estimate the prevalence of these findings and determine how frequently affected patients had "important neurosurgical outcomes," defined as either a directed intervention or a poor Glasgow Outcome Scale score. METHODS: We prospectively enrolled all blunt head trauma patients undergoing emergency head CT imaging at 18 centers participating in the National Emergency X-radiography Utilization Study II (NEXUS). From these cases, we identified all patients whose official CT reading met predefined criteria for "therapeutically inconsequential" injuries. We obtained detailed follow-up information on all such patients at 6 sites, including the need for neurosurgical intervention and Glasgow Outcome Scale scores. Among patients having "important neurosurgical outcomes," we assessed the frequency of 2 potential clinical identifiers: altered mental status and coagulopathy. RESULTS: "Therapeutically inconsequential" head CT findings were present in 155 of 8,374 subjects (1.85%; 95% confidence interval 1.57% to 2.16%). Sites participating in the follow-up study enrolled 81 of these patients, of whom 10 (12%) had "important neurosurgical outcomes." Follow-up information was available for 9 patients, all of whom had abnormal mental status at CT scanning. Coagulopathy was also present in 5 of 7 patients for whom coagulation status was known. CONCLUSION: "Therapeutically inconsequential" findings are identified in less than 2% of blunt head trauma patients who undergo CT scanning. A small proportion of these patients have an "important neurosurgical outcome," but it appears that such patients may be identified clinically by the presence of abnormal mental status or coagulopathy.

Inflammatory cytokines provide limited early prognostic information in emergency department patients with suspected myocardial ischemia.

STUDY OBJECTIVE: The aim of this study was to assess the early prognostic value of the inflammatory cytokines interleukin 6, interleukin 8, and tumor necrosis factor alpha in a cohort of emergency department (ED) patients with chest pain who have suspected myocardial ischemia. METHODS: One hundred eighteen patients with chest pain presenting to 2 urban EDs were studied. Interleukin 6, interleukin 8, and tumor necrosis factor alpha levels were assayed at presentation. The end point was the occurrence of a serious cardiac event (death, nonfatal acute myocardial infarction, myocardial revascularization, or readmission with an acute coronary syndrome) during the index admission or subsequent 3 months. RESULTS: Mean levels of all 3 cytokines were higher among patients experiencing a serious cardiac event, with the greatest differences observed in levels of interleukin 6 (mean 2.5 pg/mL [95% confidence interval (CI) 1.2 to 3.7 pg/mL] versus mean 9.8 pg/mL [95% CI 2.4 to 17.2 pg/mL]). Interleukin 6 had a sensitivity of 35% (95% CI 20% to 54%), a specificity of 86% (95% CI 76% to 92%), and an overall prognostic accuracy of 71% (95% CI 63% to 79%) for predicting serious cardiac events. However, logistic regression analysis revealed that the only independent predictor of an adverse outcome was an ECG suggestive of ischemia at presentation. CONCLUSION: Among patients presenting to the ED with suspected myocardial ischemia, higher levels of inflammatory cytokines are associated with an increased risk of a serious cardiac event during the subsequent 3 months. There is, however, considerable overlap in levels among patients who do and do not have a serious cardiac event, limiting their utility as predictors of outcome in individual patients.

Elevated soluble P-selectin levels are associated with an increased risk of early adverse events in patients with presumed myocardial ischemia.

BACKGROUND: Cell adhesion molecules (CAMs) play a pivotal role in the interactions between leukocytes, platelets, and vascular endothelium. Soluble CAMs (sCAMs) are shed from cell surfaces and reflect cellular activation. Elevated levels of sCAMs have been reported in the acute coronary syndromes. We hypothesized, therefore, that sCAMs might prove of prognostic value in patients with acute chest pain presumed to be the result of myocardial ischemia. METHODS: One hundred twenty-six consecutive patients with chest pain, thought clinically to represent myocardial ischemia, were studied prospectively. Soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), E-selectin (sE-selectin) and P-selectin (sP-selectin) levels were assayed at presentation, as were cardiac troponin I (cTnI) and creatine kinase-MB(mass) (CK-MB(mass)). The primary study end point was the occurrence of a serious cardiac event (SCE) during the index admission or the subsequent 3 months. RESULTS: sP-selectin and cTnI levels were significantly higher among patients who had an early SCE (P =.006 and P <.001, respectively). Both remained independently predictive (P <.001) in a multivariate regression equation. The other independent predictor was a history of vascular disease (P <.05). No other markers were significant predictors of early outcome. CONCLUSION: Elevated sP-selectin levels, but not those of other sCAMs, are predictors of early adverse events in patients with chest pain presumed caused by myocardial ischemia. Their utility in predicting the outcome of individual patients is, however, limited.