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Purpose: The authors wanted to identify those patients assessed by exercise SPECT in whom the quantification of lung Tl-201 uptake helps to evaluate disease prognosis., Methods: One hundred forty-nine patients (114 men, 35 women; 74 after myocardial infarction [MI]; mean age, 54 +/- 9 years) underwent exercise Tl-201 SPECT. The SPECT patterns were divided into normal (n = 45), fixed defects (n = 29), and inducible ischemia (n = 75). Anterior planar imaging was performed before SPECT acquisition to calculate the lung-to-heart ratio (L:H)., Results: During an average follow-up of 20 +/- 9 months, eight patients had died of cardiac causes and 13 patients experienced nonfatal MIs. Among the 45 patients with normal perfusion, no cardiac event was observed and the L:H ratio was not helpful for risk stratification. In 29 patients with fixed defects, four cardiac deaths occurred (all in patients with L:H ratios >0.5; annual event rate, 21.1% for L:H ratios >0.5 compared with 0% for L:H ratios <0.5; chi-square = 4.07, P < 0.05). Among the 75 patients with ischemia, 4 died and 13 had nonfatal MIs (annual event rate, 15.4% for L:H ratios >0.5 compared with 13% for L:H ratios <0.5; P = NS)., Conclusions: These findings suggest a benign prognosis in patients with normal SPECT (regardless of the L:H ratio). Conversely, all patients with ischemia are at high risk for future cardiac events. Quantification of the Tl-201 lung uptake seems to be valuable in evaluations of disease prognosis, especially in patients with fixed defects.

Purpose: The authors assessed the prognostic value of stress myocardial perfusion tomographic imaging (SPECT) in patients with recurrent angina or inconclusive results of exercise electrocardiographic tests after successful percutaneous transluminal coronary angioplasty (PTCA)., Materials and Methods: After PTCA, 70 patients (54 men, 16 women; 41 after myocardial infarction; mean age, 56 +/- 9 years) underwent TI-201 or Tc-99m sestamibi SPECT studies. SPECT patterns were divided into normal (n = 25), fixed defects (n = 15), and reversible or combined fixed plus reversible defects (n = 30). A cardiac event was defined as either cardiac death, nonfatal myocardial infarction, or unstable angina requiring further revascularization., Results: During an average follow-up of 25 +/- 10 months, two patients had severe outcomes (one cardiac death and one nonfatal myocardial infarction), and revascularization was required in 13 patients. In patients with normal SPECT or fixed defects, the annual event rate was low (1.2%), with only one revascularization. In patients with reversible or combined defects, the annual event rate was significantly greater (22.4%; chi square = 17.32, P = 0.00003)., Conclusions: Normal perfusion or fixed defects predict a benign prognosis in patients after successful PTCA. The presence of stress-induced reversible defects appears to be the best predictor of future cardiac events.

Purpose: This study used radionuclide angiography to evaluate semiquantitatively the hepatic arterial blood flow changes associated with cirrhosis., Methods: The parameters of net arterial hepatic perfusion were estimated by analysis of first-pass flow studies in 11 control participants and in 15 patients with cirrhosis (Child-Pugh classification B-C). Hepatic, renal, and splenic time-activity curves were generated, normalized per pixel, and corrected for background. The rate of hepatic arterial blood flow was compared with the reference kidney and spleen perfusion using the hepatorenal and hepatolienal perfusion indices, respectively. These indices were defined as: PI = area under hepatic curve limited by time of the renal (splenic) curve peak/area under renal (splenic) curve to its peak, Results: The values of both these perfusion indices are significantly greater in the patients with cirrhosis than in controls (hepatorenal perfusion index, P < 0.01; hepatolienal perfusion index, P < 0.05). The values of the hepatic perfusion index (the ratio of the arterial to the total liver blood flow), which were also calculated, were elevated in the patients with cirrhosis (P < 0.01)., Conclusions: The results confirm that the net hepatic arterial blood flow is increased in patients with cirrhosis. Radionuclide angiography accompanied by calculation of arterial perfusion indices may provide semiquantitative parameters of net hepatic arterial blood flow.