Prognostic role of stress thallium test in patients with significant coronary artery disease.

OBJECTIVE: The benign outcome of patients with a normal exercise thallium-201 myocardial perfusion study has been well established. The aim of the study was to examine the prognostic implications of normal exercise tomographic thallium images in medically treated patients with angiographic evidence of coronary artery disease (CAD). METHODS: There were 68 patients in Group A with significant angiographic CAD (54 male and 14 female) aged 52 +/- 12 years, 42 had one, 18 had two and eight had three vessel CAD (50% diameter stenosis 1, Group B had 70 patients who had normal coronary arteries at cardiac catheterization. RESULTS: Exercise test was submaximal in 40 (50.82%) patients, ST segment depression during exercise occurred in 28 patients (41.1%) and angina during exercise in 24 patients (35.2%). Majority of patients (76.47%) were on anti-anginal therapy. During a mean follow up of 30 months only two patients had cardiac events in group A patient. One died of cardiac causes and one had non fatal myocardial infarction (event rate 0.96%/year). None of these 2 patients had positive ST response during exercise. In group B only one patient had non-fatal myocardial infarction. CONCLUSION: Medically treated CAD patients including those with multivessel CAD have a benign prognosis in the presence of normal exercise thallium images. These results have long term important implication in management of such patients and cost of health delivery.

Scintimammography (SMM) in breast cancer patients.

The author retrospectively reviewed the scintimammography (SMM) using 201Tl and/or 99mTc-MIBI in 45 breast cancer patients. 36 cases with 37 intact breast masses and another 9 cases with previous excision of the masses were studied. The sensitivity for the detection of the primary breast cancer was 92 per cent and that of ipsilateral axillary lymph node metastasis was only 48 per cent. SMM is helpful for the diagnosis of breast cancer and differentiating malignant from benign masses, thus improving the accuracy of routine mammography. In postoperative cases SMM is helpful to detect palpable local tumor recurrence and axillary node metastasis but it is not accurate enough for assessing the extent of microscopic tumor involvement locally and also distant metastasis. Thus, it is not recommended to use SMM alone for staging of breast cancer.

Clinical symptomatology of coronary artery disease and results of exercise thallium scintigraphy: gender-related differences.

Exercise thallium stress test is the mainstay of the noninvasive assessment of patients with symptomatology suggestive of coronary artery disease. The diagnostic accuracy of thallium scintigraphy as a screening test for coronary artery disease in women as compared to men, however, remains controversial. In order to determine whether gender-related differences in the detection of coronary artery disease using exercise thallium scintigraphy are demonstrable in all age groups, we analyzed the exercise thallium results in 335 outpatients (189 male, 146 female), who were referred by their primary physicians to our institution for evaluation of clinically suspected coronary artery disease. Overall, 50.3 percent of men had a positive for ischemia thallium stress test vs 29.5 percent of women (p < 0.0002). In the subgroup of patients 65 years of age or above, 67.4 percent of men had a positive for ischemia thallium stress test vs 27.6 percent of women (p < 0.003). In the subgroup of patients upto 40 years of age, 37.9 percent of men had a positive for ischemia thallium stress test vs 25.0 percent of women (p = NS). We conclude that symptoms suggestive of coronary artery disease are less predictive of positive exercise thallium stress tests in women as compared to men even above age 65 when the prevalence of coronary artery disease is known to be similar. This suggests that women may have lower threshold for perception of symptoms or that physicians have lower threshold for referring women for screening of coronary artery disease.

X-syndrome: myocardial perfusion during stress testing.

Stress T1-201 myocardial scintigraphy was carried out in 16 patients with X-syndrome. 11 patients with ischaemic heart disease (IHD) with single vessel disease served as controls. With bicycle exercise test all 16 pts with X-syndrome had various types of myocardial perfusion abnormalities. These perfusion defects were situated in the vascular beds of different coronary arteries. Myocardial perfusion defects in patients with X-syndrome were similar to those in patients with moderate, but haemodynamically significant, single vessel disease. At the same time, these perfusion defects were significantly less pronounced than those in patients with subtotal occlusion of one coronary artery. Thus, patients with X-syndrome not only have clinical features of IHD (anginal attacks), but have marked stress-induced myocardial perfusion defects.

Semi-quantitative planar scintigraphy using thallium 201 for detection and localization of coronary artery disease: correlation with coronary angiography.

Thallium 201 exercise redistribution planar myocardial perfusion scan using semiquantitative technique was performed in 80 symptomatic patients undergoing coronary angiography. Out of the 240 vessels studied by angiography, more than 70% luminal narrowing was detected in 87 vessels, borderline stenosis was found in 49 arteries and the remaining 104 vessels were normal. Thallium scan correctly identified the significant stenosis in 76 vessels and the absence of stenosis in 102 vessels. In addition, perfusion abnormality was found in relation with 21 vessels of borderline stenosis. The sensitivity and specificity of Thallium scan were estimated as 92% and 95% for left anterior descending artery (LAD), 79% and 98% for left circumflex artery (LCX), 88% and 100% for right coronary artery (RCA) and 87% and 98% for all coronary arteries combined together (ACA).