W. Franklin Peacock

Cardiac troponins in renal insufficiency: review and clinical implications.

Patients with renal insufficiency may have increased serum troponins even in the absence of clinically suspected acute myocardial ischemia. While cardiovascular disease is the most common cause of death in patients with renal failure, we are just beginning to understand the clinical meaning of serum troponin elevations. Serum troponin T is increased more frequently than troponin I in patients with renal failure, leading clinicians to question its specificity for the diagnosis of myocardial infarction. Many large-scale trials demonstrating the utility of serum troponins in predicting adverse events and in guiding therapy and intervention in acute coronary syndromes have excluded patients with renal failure. Despite persistent uncertainty about the mechanism of elevated serum troponins in patients with reduced renal function, data from smaller groups of renal failure patients have suggested that troponin elevations are associated with added risk, including an increase in mortality. It is possible that increases in serum troponin from baseline in patients with renal insufficiency admitted to hospital with acute coronary syndrome may signify myocardial necrosis. Further studies are needed to clarify this hypothesis.

Impact of intravenous loop diuretics on outcomes of patients hospitalized with acute decompensated heart failure: insights from the ADHERE registry.

The optimal use of diuretics in decompensated heart failure remains uncertain. We analyzed data from the ADHERE registry to look at the impact of diuretic dosing. 62,866 patients receiving <160 mg and 19,674 patients ≥160 mg of furosemide were analyzed. The patients receiving the lower doses had a lower risk for in-hospital mortality, ICU stay, prolonged hospitalization, or adverse renal effects. These findings suggest that future studies should evaluate strategies for minimizing exposure to high doses of diuretics.

Ability of Troponins to Predict Adverse Outcomes in Patients With Renal Insufficiency and Suspected Acute Coronary Syndromes: A Case-Matched Study

OBJECTIVES The purpose of this study was to investigate the utility of cardiac troponin T and troponin I for predicting outcomes in patients presenting with suspected acute coronary syndromes and renal insufficiency relative to that observed in similar patients without renal disease. BACKGROUND Cardiac troponin T and troponin I have shown promise as tools for risk stratification of patients with acute coronary syndromes. However, there is uncertainty regarding their cardiac specificity and utility in patients with renal disease. METHODS We measured troponin T, troponin I and creatine kinase MB in 51 patients presenting with suspected acute coronary syndromes and renal insufficiency and in 102 patients without evidence of renal disease matched for the same peak troponin T or I value, selected from a larger patient cohort. Blood samples were obtained at presentation to an emergency room 4 hours, 8 hours and 16 hours later. The ability of biochemical markers to predict adverse outcomes in both groups including infarction, recurrent ischemia, bypass surgery, heart failure, stroke, death or positive angiography/angioplasty during hospitalization and at six months was assessed by receiver-operator curve analysis. The performance of both troponins was compared between groups. RESULTS Thirty-five percent of patients in the renal group and 45% of patients in the nonrenal group experienced an adverse initial outcome; over 50% of patients in all groups had experienced an adverse outcome by 6 months, but these differences were not significant. The area under the curve (AUC) for the ROC curve for troponin T as predictor of initial outcomes was significantly lower in the renal group than in the nonrenal group: 0.56+/-0.07 and 0.75+/-0.07, respectively. The area under the curve was also significantly lower in the renal group compared with the nonrenal group for troponin T as predictor of six month outcomes: 0.59+/-0.07 and 0.74+/-0.07, respectively. The area under the curve was also significantly lower in the renal group compared to the nonrenal group for troponin I as predictor of both initial and six month outcomes: 0.54+/-0.06 vs. 0.71+/-0.07 and 0.53+/- 0.06 vs. 0.65+/-0.07, respectively. The sensitivity of troponin T for both initial and six month adverse outcomes was significantly lower in the renal group than in the nonrenal group at a similar level of specificity (0.87): 0.29 vs. 0.60 and 0.45 vs. 0.56, respectively. Troponin I also exhibited similar differences in sensitivity in the renal group (0.29 vs. 0.50 and 0.33 vs. 0.40, respectively). CONCLUSIONS The ability of cardiac troponin T and troponin I to predict risk for subsequent adverse outcomes in patients presenting with suspected acute coronary syndromes is reduced in the presence of renal insufficiency.

Sensitivity of the Ottawa Rules

STUDY OBJECTIVE To validate criteria predicting ankle and mid-foot fractures with 100% sensitivity. DESIGN Prospective validation study SETTING A 929-bed community teaching hospital with an annual census of 76,488 ED visits. PARTICIPANTS Convenience sample of patients older than 18 years with acute ankle or midfoot injury. INTERVENTIONS Radiography was performed in each patient received after pertinent history and physical examination findings were recorded. RESULTS Five hundred seventy radiographs were obtained in 484 patients. Four hundred twenty-one were of the ankle, and 149 were of the foot. There were 93 ankle fractures and 29 midfoot fractures, giving a fracture yield of 22.1% for ankle films and 19.5% for foot films. Decision rules had sensitivity of 94.6% and specificity of 15.5% for ankle fractures and sensitivity of 93.1% and specificity of 11.5% for midfoot fractures. Prospective criteria failed to predict fracture in five of the ankle group and two of the midfoot group. Physicians predicting fracture solely on the basis of clinical suspicion had a sensitivity of 69% in ankle injuries and 76% in midfoot injuries. CONCLUSION We were unable to validate with 100% sensitivity the Ottawa rules predicting ankle and midfoot fractures. However, the Ottawa rules were more sensitive than clinical suspicion alone.

Efficacy of ketorolac tromethamine versus meperidine in the ED treatment of acute renal colic

To compare the efficacy of intramuscular ketorolac and meperidine in the emergency department (ED) treatment of renal colic, a prospective, controlled, randomized, double-blind trial was conducted in an academic ED with 76,000 annual visits. Participants were volunteer ED patients with a diagnosis of ureterolithiasis confirmed by intravenous pyelogram. Subjects were randomized 1:1 to receive a single intramuscular injection of either 60 mg ketorolac or 100 to 150 mg meperidine, based on weight. Of the 70 patients completing the trial, 33 received ketorolac and 37 received meperidine. Demographic characteristics and baseline pain scores of both groups were comparable (P = NS, Mann Whitney U). Ketorolac was significantly (P < .05) more effective than meperidine in reducing renal colic at 40, 60, and 90 minutes as measured on a 10-cm visual analogue scale. Similar proportions of patients in each group were given rescue analgesia and admitted. Of patients who were discharged home without rescue, those treated with ketorolac left the ED significantly earlier than those treated with meperidine (3.46 v 4.33 h, P < .05). These results show that intramuscular ketorolac as a single agent for renal colic is more effective than meperidine and promotes earlier discharge of renal colic patients from the ED.

Illicit Stimulant Use in a United States Heart Failure Population Presenting to the Emergency Department (from the Acute Decompensated Heart Failure National Registry Emergency Module)

Illicit stimulant drug use may have a profound clinical impact in acute decompensated heart failure (ADHF). The chronic use of cocaine and methamphetamine may lead to overt cardiomyopathy and ADHF. The Acute Decompensated Heart Failure National Registry Emergency Module (ADHERE-EM) collected data on patients presenting to emergency departments with ADHF at 83 geographically dispersed hospitals in the United States. This registry was queried to determine the rate of self-reported illicit drug use in emergency department patients presenting with ADHF and compare these patients with those without illicit drug use. The registry enrolled 11,258 patients with ADHF with drug use data from January 2004 to March 2006. Of these patients, 594 (5.3%) self-reported current or past stimulant drug use. Compared with nonusers, these patients were more likely to be younger (median age 49.7 vs 76.1 years), to be African American (odds ratio 11.9, 95% confidence interval 9.8 to 14.4), and to have left ventricular ejection fractions <40% (odds ratio 3.4, 95% confidence interval 2.8 to 4.2). Admitted users had no difference in mortality (adjusted odds ratio 0.83, 95% confidence interval 0.25 to 2.72) compared with nonusers. In conclusion, data from ADHERE-EM suggest that a clinically important percentage of patients with ADHF report the use of illicit stimulant drugs. Although these patients are younger with a greater degree of LV dysfunction, they did not have greater risk-adjusted mortality.

Clinical Decision Rules Discriminate Between Fractures and Nonfractures in Acute Isolated Knee Trauma

STUDY OBJECTIVE To develop criteria that optimize clinical decisionmaking in the use of radiography after isolated knee trauma in adults. DESIGN A prospective survey of emergency department patients over a 7-month period. Standardized data forms were completed by emergency physicians, residents, and certified physician assistants. SETTING A large suburban community teaching hospital. PARTICIPANTS Two hundred forty-two patients older than 17 years with isolated knee injuries sustained less than 24 hours previously. RESULTS We constructed a clinical decision model, calculating sensitivity, specificity, and odds ratios. Twenty-eight patients (11.6%) had fractures, with the patella the most commonly fractured osseous structure. Patients able to walk without limping had not experienced a fracture, nor had patients with twist injuries without effusion. Sensitivity of this model for detecting fracture was 1.0 (99% confidence interval, .97 to 1.0), and specificity was .337 (99% confidence interval, .26 to .42). CONCLUSION Clinical decision rules are effective in detecting knee fractures with 100% sensitivity and with sufficient specificity to eliminate 29% of knee radiographs in the ED. These findings require prospective validation.

Effect of a Patient's Sex on the Timing of Thrombolytic Therapy

STUDY OBJECTIVE We sought to determine whether a patients sex independently influences the interval from emergency department arrival to the initiation of thrombolytic therapy in acute myocardial infarction (AMI). METHODS We conducted a retrospective cohort study in two suburban EDs, one at a 929-bed tertiary care teaching hospital and the other at a 189-bed community hospital. Only patients found to be having an ST-segment-elevated AMI on their first ECG who were treated with a thrombolytic agent in the ED were eligible. We excluded patients who arrived at the ED after cardiac arrest or with a known AMI. We used as the main outcome measure the interval from ED arrival to initiation of thrombolytic therapy. Secondary outcome variables included time elapsed before ECG, interval between ECG and treatment, and 1-year mortality. RESULTS Entry criteria were satisfied by 328 patients. The 88 women experienced a mean 23-minute delay to treatment initiation compared with men (P < .01). This observation is not accounted for by age, race, time of day, medical history, sex of the physician, type of thrombolytic agent, hospital, or triage category. The longest delays were found in women treated by female physicians, although female physicians also waited longer than male physicians to administer thrombolytic therapy to men. The mean time elapsed before the first ECG was also 6 minutes longer for women (P < .01) Women had an increased 1-year mortality rate that was fully explained by their advanced age at the time of AMI. CONCLUSION We infer that a patients sex may play a significant role in the observed delay in treatment for women. Our data, coupled with previously published work, strongly suggest a systematic negative effect for women in their interaction with the health care system during AMI. We suggest that variables other than systems issues affect the time elapsed before thrombolytic therapy.

Risk stratification in women enrolled in the Acute Decompensated Heart Failure National Registry Emergency Module (ADHERE-EM)

OBJECTIVES It has been reported that the mortality risk for heart failure differs between men and women. It has been postulated that this is due to differences in comorbid features. Variation in risk profiles by gender may limit the performance of stratification algorithms available for heart failure in women. This analysis examined the ability of a published risk stratification model to predict outcomes in women. METHODS The Acute Decompensated Heart Failure National Registry Emergency Module (ADHERE-EM) database was used. Characteristics, treatments, and outcomes for men and women were compared. The ADHERE registry classification and regression tree (CART) analysis was used for the risk stratification evaluation. RESULTS Of 10,984 ADHERE-EM patients, 5,736 (52.2%) were women. In-hospital mortality was similar between men and women (p = 0.727). Significant differences (p < 0.0002) were noted by gender in all three variables in the CART model (blood urea nitrogen [BUN] > or = 43 mg/dL, systolic blood pressure < 115 mm Hg, and serum creatinine > or = 2.75 mg/dL). However, the CART model effectively stratified both genders into distinct risk groups with no significant difference in mortality by gender within stratified groups. CONCLUSIONS The ADHERE Registry CART tool is effective at predicting risk in ED patients, regardless of gender.

Will SCUBE1 solve the ischemia marker deficit

In this issue of the Journal , Dai et al. ([1][1]) report their findings regarding plasma SCUBE1. This marker, a protein associated with platelet-endothelial interactions, may be indicative of platelet activation occurring during acute ischemic events. The significance of detecting this interaction