Minimum detectable defect thickness in SPECT myocardial perfusion test: phantom study with (99m)Tc and (201)Tl.

OBJECTIVE: The purpose of this study was to determine experimentally the minimum thickness (D(min)) of a defect inserted on the myocardial wall of a cardiac phantom at different locations that could be clearly detected in a SPECT perfusion study using (99m)Tc and (201)Tl. METHODS: Rectangular (or cylindrical) defects with the same thickness were inserted on the inner surface of a myocardial phantom at 5 different locations: anterior (ANT), septal (SEP), inferoposterior (IP), lateral (LAT), and apical (AP). For different defect thickness (from 1 to 7 mm, in increments of 1 mm) the myocardial SPECT perfusion study was performed with (99m)Tc and (201)Tl using the same protocol that we use for patients. Baseline studies (with no defect inserted) were also performed. The SPECT images of the myocardial phantom with defects were compared with baseline SPECT images to determine whether the defect could be clearly identified. RESULTS: The uniformity of the baseline SPECT images was analyzed very carefully where an IP artifact was detected. The D(min) was determined for (99m)Tc and (201)Tl at 3 radii of rotation: 21.0, 25.0, and 29.2 cm. CONCLUSION: To be detected on SPECT images, a defect must be of a thickness > or =D(min). A simple method for performing a quality control test for SPECT nuclear cardiology can be developed based on these findings.

Staphylococcal pericarditis following percutaneous transluminal coronary angioplasty.

Infectious complications occurring after percutaneous transluminal coronary angioplasty are uncommon. We are reporting a case of bacterial pericarditis developing 1 week after coronary angioplasty and stent implantation. Treatment with appropriate antibiotics and drainage of the infected pericardial effusion was followed by a protracted hospital course and eventual control of infection and discharge of the patient.

Refractory vasospasm with a malignant course.

We present a patient with two rare disorders, recurrent vasospastic angina leading to cardiac transplant and acute aortic occlusion. The patient had recurrent episodes of coronary vasospasm presenting with unstable angina, acute myocardial infarction, and sudden cardiac death in spite of adequate therapy with nitrates and calcium-channel blockers. He went on to have a cardiac transplant. The patient later presented with acute aortic occlusion with concomitant renal and mesenteric artery spasm. The circumstances of the presentation raise the possibility of a generalized vasospastic predisposition that is responsible for both events. Smoking, the only known major risk factor other than atherosclerosis, was noted to be temporally related to both events in our patient.

Electrocardiographic patterns of patients with echocardiographically determined biventricular hypertrophy.

The numerous criteria proposed for the electrocardiographic (ECG) diagnosis of biventricular hypertrophy (BVH) suffer from inadequate correlative data. We used two-dimensional (2D) echocardiography to identify BVH and analyzed the ECG patterns in these patients. The study group had 69 such patients with BVH and the control group had 22 patients with isolated left ventricular hypertrophy (LVH) demonstrated by 2D echocardiography. The electrocardiograms were analyzed for the presence of established criteria used in the diagnosis of LVH and right ventricular hypertrophy (RVH). Of the 69 patients in the study group, 17 (25%) had ECG findings of BVH, 25 (36%) had LVH, and 14 (20%) had RVH. An S wave in V5/V6 of >7 mm was most the frequent finding in the 17 patients with BVH on the electrocardiogram. The sensitivity of ECG criteria for BVH was 24.6%, specificity was 86.4%, and positive predictive value was 85%. This study reemphasizes the difficulty of ECG diagnosis of BVH. The electrocardiogram has a low sensitivity but satisfactory specificity and positive predictive accuracy for BVH.

Aortic dissection in a young corticosteroid-treated patient with systemic lupus erythematosus--a case report.

We report a rare case of acute aortic dissection in a young, corticosteroid-treated hypertensive patient with a long-standing history of systemic lupus erythematosus (SLE). A brief review of literature on aortic dissection in lupus erythematosus is presented. A low threshold for performing transesophageal echocardiography in the management of chest pain syndrome in SLE is emphasized.

Breast abscess: coagulase-negative staphylococcus as a sole pathogen.

Breast abscesses in nonlactating women are very uncommon. Rarely have cases been reported in which coagulase-negative staphylococci have been isolated in pure culture. We describe a 67-year-old patient who had such an abscess. Specimens obtained by fine needle aspiration, incision and drainage, and biopsy of the breast mass all showed acute inflammation and many gram-positive cocci on gram stain and histologic examination; cultures of all specimens yielded many coagulase-negative staphylococci. The patient responded well to incision and drainage and therapy with antibiotics.