CT in tuberculous constrictive pericarditis.

Constrictive pericarditis (CP) and restrictive cardiomyopathy have the same pathophysiological disorder (impaired diastolic filling) and a similar presentation. To determine the value of a noninvasive technique, CT, in differentiating between the two, we reviewed the CT scans of 212 patients with clinical signs and symptoms of CP and/or restrictive cardiomyopathy, after 26 cases that did not proceed to surgery were excluded. Computed tomography showed pericardial thickening (greater than 3 mm) in 157 patients with proven tuberculous CP. In two children with proven constriction, the pericardium measured between 2 and 3 mm. We determined that pericardial thickening, in the correct clinical setting, is the only CT sign necessary to diagnose CP. Other CT signs, inferior vena cava dilatation (97%), and deviation of the interventricular septum (15%) were confirmatory. Computed tomography accurately differentiates between CP and restrictive myocardial disease, making more invasive modalities such as cardiac catheterization and endomyocardial biopsy, with few exceptions, unnecessary.

Comparison of patient responses to high- and low-osmolality contrast agents injected intravenously.

Low-osmolar intravascular radiographic contrast media have recently been introduced for clinical use in an attempt to reduce the frequency and severity of side effects. This study was undertaken to test patients' subjective reactions to IV injection of three different types of contrast media--iopamidol, meglumine/sodium ioxaglate, and sodium iothalamate. The low-osmolar contrast media (ioxaglate, iopamidol) were found to have a significantly lower frequency of nonidiosyncratic reactions than the high-osmolar contrast media (iothalamate). However, in view of the present cost of low-osmolar contrast media and the relatively minor nature of nonidiosyncratic reactions, it is concluded that high-osmolar contrast media should remain the contrast media of choice for routine IV use.