Faculty Bibliography

Ultrafast computed tomography (CT) is a new imaging technique that relies on electron beam technology. Its short scanning acquisition times eliminate the motion artifacts seen with conventional CT. High temporal and spatial resolution make it ideal for evaluating the heart using only modest amounts of intravenous contrast. Ultrafast CT is extremely valuable for diagnosis and assessment of intracardiac thrombus and cardiac tumors. Although echocardiography is widely used to identify intracardiac thrombus, it sometimes cannot visualize the most common sites, the atria (especially the left atrial appendage) and the cardiac apex. These areas are clearly defined by ultrafast CT. Likewise, the location, size, extent, and tissue density of primary or metastatic cardiac tumors can be characterized using ultrafast CT, which may obviate the need for angiography before operative treatment.

Rapid and accurate detection of great vessel disease is of enormous importance in clinical practice. The search continues for the best technique to evaluate critically ill patients with acute aortic dissection and/or acute pulmonary embolism. Because of its speed and excellent spatial resolution, ultrafast computed tomography (CT) is a very useful tool and may alter the management of patients with aortic disease. Other techniques, such as magnetic resonance imaging (MRI) and transesophageal echocardiography (TEE) are also used in the diagnosis of aortic dissection. Each technique has advantages and pitfalls. At this time it is likely that one technique will complement the other. With further technical improvements, both MRI and ultrafast CT are likely to emerge as the diagnostic tests of choice. In the future, further validation and comparative studies in the acute setting may help to identify the most accurate and useful technique.

The incremental diagnostic value of exercise electrocardiographic testing compared with clinical data alone in the diagnosis of coronary artery disease (CAD) was found to be of limited value in a previous study. That study used a computer algorithm for diagnosing disease. Thus, the strict use of the results apply only to computerized disease diagnosis rather than physicians' diagnoses. The aim of the present study was to determine whether exercise test data improve a physician's ability to detect the presence or absence of CAD and 3-vessel or left main CAD, and whether the data effect the decision to perform angiography. The study sample comprised a data base of 312 patients whose clinical data, exercise test results and coronary anatomy were known. Individual cases were presented to 8 cardiologists with and without exercise data. The cardiologists provided estimates of disease probability and were asked whether they would request coronary angiography. Receiver-operating characteristic curves and goodness-of-fit analysis showed better discrimination and calibration of the estimates for the presence of CAD and 3-vessel/left main CAD after exercise test results were known. Individualized probability thresholds for deciding whether to request angiography were determined for each physician. Forty-three percent of patients crossed greater than or equal to 1 threshold, with 64% of the crossings in the correct direction. For estimating the presence of any CAD, 84% of crossings from below to above a threshold were correct, whereas only 36% from above to below were correct. For 3-vessel/left main CAD, 36% of crossings from below to above a threshold were correct, whereas 88% from above to below were correct.(ABSTRACT TRUNCATED AT 250 WORDS)