Stephen D Greenwood | PubMed Health

PubMed2006

Non-invasive resting magnetocardiographic imaging for the rapid detection of ischemia in subjects presenting with chest pain.

BACKGROUND: Early diagnosis of ischemia is complicated by the poor sensitivity of standard tests and contraindication for stress testing in unstable angina patients. Magnetocardiography (MCG) imaging can be used for the rapid, non-invasive detection of ischemia at rest. METHODS: We studied 125 patients with presumed ischemic chest pain. All were chest pain free at the time of scanning. A 6-minute resting MCG scan (CardioMag Imaging, Inc., New York, 9-channel system) was performed. Following the MCG scan, automated software data analysis was performed, and quantitative scores were automatically calculated for each subject. The presence of ischemia was determined after testing with serial troponins, stress testing, and/or coronary angiography. RESULTS: The mean age was 59.4 +/- 13.6 years. Most patients (86.4%) had non-ischemic 12-lead ECG and normal troponin (86.2%). Fifty-five patients (44.0%) were determined to be ischemic. The MCG sensitivity, specificity, positive and negative predictive value was 76.4, 74.3, 70.0 and 80.0%, respectively, for the detection of ischemia (p < 0.0001). CONCLUSIONS: MCG is a new rapid, non-invasive imaging tool able to detect repolarization abnormalities at rest consistent with ischemia in patients presenting with chest pain syndrome and normal or non-specific 12-lead ECG and normal troponin.

Adult↗

PubMed2004

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.

Adolescent↗