Proton nuclear magnetic resonance imaging of regionally ischemic canine hearts: effect of paramagnetic proton signal enhancement

In a study to evaluate the potential of proton nuclear magnetic resonance (NMR) imaging with and without manganese contrast with and without manganese contrast enhancement for detecting acute myocardial infarction, 12 dogs underwent 90-minute occlusion of the left circumflex coronary artery. Transverse-section NMR images of the excised, nonbeating heart were obtained at 1-cm intervals using the steady-state-free-precession (SSFP) technique. All NMR images revealed detailed structure of the heart. The three hearts without manganese showed no difference in intensity between the normal and the ischemic posterior regions, whereas those with manganese demonstrated a clearly demarcated zone of reduced signal intensity consistent with the ischemic zone. It is concluded that high-resolution tomograms of the excised canine myocardium can be obtained using proton NMR imaging. With the SSFP imaging technique, proton signal enhancement with manganese infusion is necessary to differentiate between ischemic and nonischemic myocardium after 90 minutes of coronary occlusion.     

Influential Factors of Student Evaluations of Teaching in a Nursing Program

We used a logistic regression model to analyze data from routinely collected student evaluation of teaching from 2,211 nursing students over 8 semesters. The results showed that not all aspects of teaching are equally influential in their effects on students' overall rating of instructors' teaching as excellent. Influential aspects include motivation, individual assistance, presentation of concepts, environment, and practical application. The most influential evaluation aspect is motivation.     

Simultaneous operation of off pump coronary artery bypass and abdominal aortic aneurysm repair

Objectives: Coronary artery disease (CAD) and abdominal aortic aneurysms (AAA) commonly coexist. However, each disease treatment complicates the management of the other. In this study, we evaluate whether a simultaneous operation of AAA repair and off pump coronary artery bypass (OPCAB) would be safe and acceptable, compared with either procedure alone. Subjects and Methods: We retrospectively reviewed all patients who underwent simultaneous AAA repair and OPCAB (AAA/OPCAB, n=18), compared AAA repair alone (AAA, n=239) and OPCAB alone (OPCAB, n=137) from June 1999 to December 2003. There were no significant differences with regard to age or gender, but the AAA/OPCAB group had significantly larger aneurysms (60.6 vs. 53.2 mm) and significantly lower ejection fractions (EF) (54.9 vs. 60.3%). Results: The patients in the AAA/OPCAB group underwent a significantly longer operative time than AAA, OPCAB (403 vs. 360,296 minutes, respectively), there was significantly greater blood loss (726 vs. 426, 462 ml), and more transfusion required (8.13 vs. 1.69, 2.8 units). The number of bypass grafts in AAA/OPCAB group (1–5 per patients) was significantly smaller (1.78 vs. 2.93). The AAA/OPCAB patients had a significantly longer hospital stay than the AAA (38 vs. 22 days), but was not significantly longer than the OPCAB. There were no significant differences with regard to the morbidity and mortality rate among the three groups. Conclusion: This study suggests that the simultaneous operation of AAA and OPCAB can be done with the same morbidity and mortality as independent surgical procedures. Key words: coronary artery bypass grafting, abdominal aortic aneurysm, off pump coronary artery bypass, simultaneous operation     

Acquired cutaneous lymphangiectasia

Summary We report a case of acquired cutaneous lymphangiectasia associated with underlying malignancy, and following an arthrotomy. Clinical and histological features were identical with those of acquired lymphangioma. Lymphangiography showed signs of acquired lymphatic obstruction. Both the underlying tumour and the arthrotomy were thought to be contributory factors.