Comparison of conventional and high-sensitivity troponin in patients with chest pain: a collaborative meta-analysis.

BACKGROUND: Multiple studies have evaluated the diagnostic and prognostic performance of conventional troponin (cTn) and high-sensitivity troponin (hs-cTn). We performed a collaborative meta-analysis comparing cTn and hs-cTn for diagnosis of acute myocardial infarction (AMI) and assessment of prognosis in patients with chest pain. METHODS: MEDLINE/PubMed, Cochrane CENTRAL, and EMBASE were searched for studies assessing both cTn and hs-cTn in patients with chest pain. Study authors were contacted and many provided previously unpublished data. RESULTS: From 17 included studies, there were 8,644 patients. Compared with baseline cTn, baseline hs-cTn had significantly greater sensitivity (0.884 vs 0.749, P < .001) and negative predictive value (NPV; 0.964 vs 0.935, P < .001), whereas specificity (0.816 vs 0.938, P < .001) and positive predictive value (0.558 vs 0.759, P < .001) were significantly reduced. Based on summary receiver operating characteristic curves, test performance for the diagnosis of AMI was not significantly different between baseline cTn and hs-cTn (0.90 [95% CI 0.85-0.95] vs 0.92 [95% CI 0.90-0.94]). In a subanalysis of 6 studies that alternatively defined AMI based on hs-cTn, cTn had lower sensitivity (0.666, P < .001) and NPV (0.906, P < .001). Elevation of baseline hs-cTn, but negative baseline cTn, was associated with increased risk of death or nonfatal myocardial infarction during follow-up (P < .001) compared with both negative. CONCLUSION: High-sensitivity troponin has significantly greater early sensitivity and NPV for the diagnosis of AMI at the cost of specificity and positive predictive value, which may enable early rule in/out of AMI in patients with chest pain. Baseline hs-cTn elevation in the setting of negative cTn is also associated with increased nonfatal myocardial infarction or death during follow-up.

Short-term (90 min) diagnostic performance for acute non-ST segment elevation myocardial infarction and 30-day prognostic evaluation of a novel third-generation high sensitivity troponin I assay.

OBJECTIVES: We evaluated a third-generation high sensitivity "guidelines acceptable" troponin I assay (hs-cTnI) against a contemporary "clinically usable" troponin assay (cTnI). DESIGN AND METHODS: Remnant samples of undifferentiated emergency department (ED) patients with suspected acute coronary syndrome were enrolled. Baseline and 90-minute samples were analyzed for cTnI and hs-cTnI. Sensitivity, specificity, positive and negative predictive values for AMI and 30-day adverse cardiac events (ACE) were compared. RESULTS: Of 486 ED patients, there were 465 patients who had blood remaining at the presentation for the hs-cTnI assays, with 12 AMIs. At presentation, the clinical sensitivity and specificity for AMI was 75% and 97% for cTnI and 83.3 and 82.1% for hs-cTnI. There were 407 patients who had paired baseline and 90-minute blood samples for cTnI and hs-cTnI including 9 of the 12 AMI patients. The sensitivity and specificity was 77.7% and 96.5% for cTnI and 100% and 81.9% for hs-cTnI at 90 min. A Δ change of 30% increase from baseline to 90 min improved the specificity to 94.5% (95% CI 92%-96%) without lowering the sensitivity. When AMI was defined as a Δ30% change of hs-cTnI at t=0 and 90 min and one hs-cTnI result >99th percentile cutoff, more than 3 times as many patients met the diagnostic criteria for AMI compared to results from the normal sensitive troponin assay; 28 (6.9%) for hs-cTnI vs. 9 (2.2%) with cTnI. There were 37 in-hospital or 30-day events, producing an OR of 3.03, 95% CI: 0.86-9.59 for cTnI, and 2.54, 95% CI: 1.27-5.10 for hs-cTnI, which detected 11 more cases. CONCLUSIONS: The hs-cTnI assay achieved a 90-minute rule out for AMI and detected more 3 times as many AMI cases. The specificity increased with the Δ30% criteria. The hs-cTnI assay also detected more cases of patient at risk for adverse cardiac events at 30 days.

Therapy and outcomes in massive pulmonary embolism from the Emergency Medicine Pulmonary Embolism in the Real World Registry.

STUDY AIM: Clinical guidelines recommend fibrinolysis or embolectomy for acute massive pulmonary embolism (PE) (MPE). However, actual therapy and outcomes of emergency department (ED) patients with MPE have not previously been reported. We characterize the current management of ED patients with MPE in a US registry. METHODS: A prospective, observational, multicenter registry of ED patients with confirmed PE was conducted from 2006 to 2008. Massive PE was defined as PE with an initial systolic blood pressure less than 90 mm Hg. We compared inpatient and 30-day mortality, bleeding complications, and recurrent venous thromboembolism. RESULTS: Of 1875 patients enrolled, 58 (3.1%) had MPE. There was no difference in frequency of parenteral anticoagulation (98.3% [95% confidence interval {CI}, 90.5-101.6] vs 98.5% [95% CI, 97.9-99.1], P = .902) between patients with and without MPE. Fibrinolytic therapy and embolectomy were infrequently used but were used more in patients with MPE than in patients without MPE (12.1% [95% CI, 3.7-20.5] vs 2.4% [95% CI, 1.7-3.1], P < .001, and 3.4% [95% CI, 0.0-8.1] vs 0.7% [95% CI, 0.3-1.1], P = .022, respectively). Comparison of outcomes revealed higher all-cause inpatient mortality (13.8% [95% CI, 4.9-22.7] vs 3.0% [95% CI, 2.2-3.8], P < .001), higher risk of inpatient bleeding complications (10.3% [95% CI, 2.5-18.1] vs 3.5% [95% CI, 2.7-4.3], P = .007), and a higher 30-day mortality (14.0% [95% CI, 4.4-23.6] vs 1.8% [95% CI, 1.2-2.4], P < .001) for patients with MPE. CONCLUSIONS: In a contemporary registry of ED patients, MPE mortality was 4-fold higher than patients without MPE, yet only 12% of the MPE cohort received fibrinolytic therapy. Variability exists between the treatment of MPE and current recommendations.

Statin-induced rhabdomyolysis.

Simvastatin and other HMG-CoA reductase inhibitors (statins) are one of the most frequently prescribed class of medications in the United States, with over 15 million Americans taking these drugs. Relatively rare adverse effects related to the known toxic effects of these drugs are more common than generally realized. Clinically significant statin-induced rhabdomyolysis is an uncommon but life-threatening adverse effect. We describe a case of simvastatin-induced rhabdomyolysis. Current knowledge of the pharmacology of the HMG-CoA reductase inhibitors and the drug interactions that potentiate these adverse effects are discussed. The clinical features of rhabdomyolysis and current treatment recommendations are presented.

Paroxysmal atrial fibrillation precipitated by amiodarone-induced thyrotoxicosis five months after cessation of therapy.

Amiodarone is currently indicated for the treatment of life-threatening ventricular dysrhythmias. It is also used for the treatment of supraventricular dysrhythmias and as maintenance therapy after successful cardioversion of atrial flutter or atrial fibrillation. Adverse effects related to its expanded use are increasingly common. We describe a case of amiodarone-induced thyrotoxicosis occurring 5 months after cessation of therapy and discuss the pathophysiology and treatment of this disorder.

Drug-related emergency department visits in an elderly veteran population.

BACKGROUND: Given that adverse drug events result in extensive costs and healthcare resource utilization, the goal is to better understand drug-related emergency department (ED) visits so that programs can be implemented to improve the quality of health care. OBJECTIVE: To (1) determine the incidence of drug-related ED visits at a large, tertiary care, Veterans Affairs hospital; (2) identify causes of these drug-related ED visits; (3) determine patient outcomes, healthcare resource utilization, and costs associated with these visits; and (4) determine the proportion of adverse drug reaction (ADR)-related ED visits that were spontaneously reported to the hospital's ADR reporting program. METHODS: We conducted a retrospective electronic chart review of all patients who visited the ED during the second week of each month in 2003. Causes for drug-related visits were identified. ADRs in this study included side effects, drug allergies, and drug-drug interactions (DDIs) and were assessed using the Naranjo probability scale. RESULTS: A total of 2169 patients were included in the study. Drug-related visits accounted for 12.6% of all ED visits. The main causes of drug-related visits were ADRs and nonadherence, which accounted for 33% and 19% of drug-related visits, respectively. Only 11% of these ADRs were spontaneously reported to the hospital's ADR reporting program. Thirty-five percent of drug-related visits led to hospitalizations, which resulted in an average length of stay of 9.3 days. The institution's total cost of drug-related visits was approximately 1.5 million US dollars over 12 weeks. CONCLUSIONS: Many ED visits are drug related and often result in hospitalization and increased healthcare resource utilization. Only a minimal number of the ADRs resulting in ED visits are spontaneously reported to hospital ADR reporting programs.

Adverse cardiac events in emergency department patients with chest pain six months after a negative inpatient evaluation for acute coronary syndrome.

OBJECTIVE: To evaluate the impact of the diagnostic test setting-inpatient versus outpatient-on adverse cardiac events (ACEs) after six months in emergency department (ED) patients with chest pain who were admitted to the hospital and subsequently had a negative evaluation for acute coronary syndrome (ACS). METHODS: The authors retrospectively studied a consecutive sample of ED patients with chest pain over a nine-month period. All patients were admitted to the hospital and underwent negative evaluations for ACS, defined as the absence of diagnostic changes on serial electrocardiograms or cardiac markers (creatine kinase-MB and troponin T), and a negative diagnostic cardiac study. Subjects were classified according to cardiac diagnostic study setting-either inpatient or outpatient. Diagnostic testing included exercise treadmill, angiography, stress echocardiography, or stress thallium scans. Acute cardiac events at six months were defined as cardiac death, myocardial infarction, unstable angina, cardiac arrest, or emergent revascularization. RESULTS: The six-month rate of ACEs among 157 subjects was 14%, with 2% cardiac mortality. The outpatient group had higher ACE risk when compared with the inpatient group using multivariate logistic regression, both for the entire cohort (OR 3.5, p < 0.03) and for a subgroup excluding patients with prior coronary artery disease (OR 6.7, p < 0.05). The outpatient group included 19 of 52 (37%) noncompliant subjects who did not receive a diagnostic study. CONCLUSIONS: Long-term cardiac morbidity of patients after a negative ACS evaluation may be higher than previously thought. Risk of ACE is significantly higher in subjects scheduled for outpatient diagnostic tests. Inpatient diagnostic testing is justified for subjects at risk for poor compliance.