The authors compared retrospectively the diagnostic accuracy of three protocols - 201 Tl stress -redistribution, 2-day 99m Tc-tetrofosmin and the dual-isotope protocol (rest 201 Tl/stress 99m Tc-tet- rofosmin) - for the detection of ischaemic heart disease (IHD) in a total of 115 patients without previous myocardial infarction (IM). 201 Tl protocol (group A) was used to examine 43 patients, incl. 15 women, mean age 51 years (38-69 years). The 2-day 99m Tc-tetrofosmin protocol was used to examine 39 patients incl. 12 women, mean age 49 years(30-71 years). The dual-isotope protocol was used in 33 patients , incl. 8 women , mean age 52 years (31-69 years). In all patients coronarog- raphy was performed, stenosis of the artery > 50% was considered significant for IHD. The sensiti- vity of the dual-isotope protocol was 95% and 96% resp. and 92% in the 2-day tetrofosmin and 201 Tl protocol, (p>0.05). The specificity of the dual-isotope protocol was 82% and 89% resp. and 88% in the 201 Tl and 2-day tetrofosmin protocol, (p >0.05). The diagnostic accuracy was 91% in the dual- isotope and 201 Tl protocol and 92% in the 2-day protocol (p>0.05). No significant difference was revealed in the sensitivity, specificity and diagnostic accuracy for the detection of IHD between different protocols in patients without previous IM.

        Key words: Myocardial perfusion - SPECT - CAD - Dual-isotope protocol