The prognostic value of myocardial perfusion scintigraphy compared to coronary angiography in women with positive stress test results

Abstract

BACKGROUND: Modern diagnostic strategy in coronary arterydisease (CAD) makes it necessary not only to establish a diagnosisbut also to assess the cardiovascular risk. It is not clearwhich strategy should be followed in the case of women withpositive ECG stress test results to assess prognosis and startappropriate diagnostics and treatment.The aim of the study was to assess the prognostic value ofmyocardial perfusion scintigraphy in comparison with coronaryangiography in women suspected of CAD and with positive ECGstress test results.

MATERIAL AND METHODS: The study population comprised115 women (mean age 58.08 ± 8.8 years) suspected of CAD, witha history of chest pain and positive stress test results, who underwent myocardial perfusion scintigraphy. In 58 women coronaryangiography was performed as the next step of the diagnosticprocedure. All the patients were interviewed and had a physicalexamination, including the assessment of the cardiovascularrisk in accordance with the SCORE (Systematic Coronary RiskEvaluation) scale and the probability of CAD (POST-TEST) inaccordance with the ESC guidelines. The gated single photonemission computed tomography (GSPECT) with Tc-99m-MIBIwas considered positive if moderate perfusion changes wereobserved in at least two segments or severe reversible perfusiondisorders were found, regardless of the number of involved segments.The degree of coronary stenosis was assessed visuallyand changes greater than 50% stenosis of the luminal diameterwere considered haemodynamically significant.

RESULTS: The evaluation period covered 43.2 ± 30.8 monthson average. The sensitivity of myocardial perfusion scintigraphyagainst cardiovascular events was 100% and the sensitivity ofcoronary angiography was 92.3%. The specificity was 93.1%and 88.9% respectively.The PPV of scintigraphy for cardiovascular events was 65% and ofcoronary angiography was 70.6%. The NPV was 100% and 97.6%respectively. The accuracy of myocardial perfusion scintigraphy forcardiovascular events was 93.9% and the accuracy of coronaryangiography for cardiovascular events was 89.7%. The survivalanalysis confirmed the high prognostic value of SPECT and coronaryangiography. However, if compared, myocardial perfusionscintigraphy was a better predictor of survival without cardiovascularevents than coronary angiography was (c2 = 9.39, p < 0.01).The most important factors in assessing the cardiovascular riskin the study population included: positive result of myocardialperfusion scintigraphy, positive result of coronary angiography,and high SCORE and high POST-TEST values.

CONCLUSIONS: Myocardial perfusion scintigraphy is superiorto coronary angiography in the prediction of necessary revascularisation procedures in women suspected of coronary arterydisease and with positive stress test results.