Faculty Bibliography

OBJECTIVE: Dual-source CT improves temporal resolution, and theoretically improves the diagnostic image quality of coronary artery examinations without requiring preexamination beta-blockade. The purpose of our study was to show the improved diagnostic image quality of dual-source CT compared with single-source CT despite the absence of preexamination beta-blockade in the dual-source CT group. MATERIALS AND METHODS: We performed a retrospective analysis of consecutive patients who underwent coronary artery evaluation with either single-source CT or dual-source CT at our institution between February 2005 and October 2006. Examination reports were analyzed for the presence of image artifacts, and image quality was graded on a 3-point scale (no, mild, or severe artifact). Type of artifact (motion, calcium, quantum mottle) was also noted. RESULTS: Examinations (339 single-source CT and 126 dual-source CT) of 465 patients were analyzed. Artifact was reported in 39.8% of examinations using single-source CT and in 29.4% of examinations using dual-source CT (p < 0.05). The number of examinations with motion artifact was significantly higher with single-source CT than with dual-source CT (15.9% vs 4.8%; p < 0.001) despite significantly higher heart rates in the dual-source CT group (59.4 +/- 8.4 vs 68.6 +/- 14.6 beats per minute; p < 0.001). No patients in the dual-source CT group received preexamination beta-blockade compared with 81% of patients in the single-source CT group. The presence of severe (nondiagnostic) calcium artifact was also significantly reduced in the dual-source CT group (13.0% vs 3.2%; p < 0.001). CONCLUSION: Dual-source CT provides significantly better diagnostic image quality than single-source CT despite higher heart rates in the dual-source CT group. These findings support the use of dual-source CT for coronary artery imaging without the need for preexamination beta-blockade

Cardiac sarcoidosis (CS) is a rare but potentially fatal condition that may present with a wide range of clinical manifestations including congestive heart failure, conduction abnormalities, and most notably, sudden death. Recent advances in imaging technology allow easier detection of CS, but the diagnostic guidelines with inclusion of these techniques have yet to be written. It has become clear that minimally symptomatic or asymptomatic cardiac involvement is far more prevalent than previously thought. Because of the potential life-threatening complications and potential benefit of treatment, all patients diagnosed with sarcoidosis should be screened for cardiac involvement. Patients with CS and symptoms such as syncope need an aggressive workup for a potentially life-threatening etiology, and often require implantable cardioverter-defibrillator therapy. CS patients without arrhythmic symptoms are still at risk for sudden death and may warrant an implantable cardioverter-defibrillator for primary prevention reasons. Although corticosteroids are regarded as the first-line drug of choice, therapy for CS is not yet standardized, and it is unclear at this point whether asymptomatic patients require therapy. Randomized clinical trials are clearly warranted to answer these very important patient care questions, and are endorsed fully by the authors

A 79-year-old woman with severe aortic stenosis underwent aortic valve replacement surgery, and had ligation of the left atrial appendage (LAA) using an epicardial approach. On a post-operative echocardiographic evaluation, the distal portion of the LAA was excluded, leaving no communication with the left atrium. The proximal portion of the LAA, however, was in continuity with the circulation and a large thrombus was present within it. While previous reports of incomplete LAA ligation have involved disruption of the suture line, this present report describes a case of incomplete ligation due to persistence of the proximal portion of the appendage. Thus, thrombus formation occurred despite a 'successful' epicardial exclusion of the distal LAA

The goal of our study was to determine the prevalence of older patients with cardiac valvular abnormalities warranting endocarditis prophylaxis. We performed a retrospective analysis of 1,000 randomly selected echocardiograms (inpatients and outpatients) from our tertiary care institution. We found that the prevalence of valvular abnormalities increased significantly with age, and that 50% of patients > or =60 years of age warranted endocarditis prophylaxis using current guidelines. With the aging population of the United States and the negative consequences of widespread antibiotic prophylaxis, further investigation is needed to identify patients who are truly at risk for infectious endocarditis

OBJECTIVE: Few studies have evaluated the parietal lobe in schizophrenia despite the fact that it has an important role in attention, memory, and language-all functions that have been reported to be abnormal in schizophrenia. The inferior parietal lobule, in particular, is of interest because it is not only part of the heteromodal association cortex but also is part of the semantic-lexical network, which also includes the planum temporale. Both the inferior parietal lobule, particularly the angular gyrus of the inferior parietal lobule, and the planum temporale are brain regions that play a critical role as biological substrates of language and thought. The authors compared volume and asymmetry measures of the individual gyri of the parietal lobe by means of magnetic resonance imaging (MRI) scans. METHOD: MRI scans with a 1. 5-Tesla magnet were obtained from 15 male chronic schizophrenic and 15 comparison subjects matched for age, gender, and parental socioeconomic status. RESULTS: Inferior parietal lobule volumes showed a leftward asymmetry (left 7.0% larger than right) in comparison subjects and a reversed asymmetry (left 6.3% smaller than right) in schizophrenic subjects. The angular gyrus accounted for this difference in asymmetry, with the left angular gyrus being significantly larger (18.7%) than the right in comparison subjects, a finding that was not observed in schizophrenic patients. A further test of angular gyrus asymmetry showed a reversal of the normal left-greater-than-right asymmetry in the schizophrenic patients. CONCLUSIONS: Patients with schizophrenia showed a reversed asymmetry in the inferior parietal lobule that was localized to the angular gyrus, a structure belonging to the heteromodal association cortex as well as being part of the semantic-lexical network. This finding contributes to a more comprehensive understanding of the neural substrates of language and thought disorder in schizophrenia.