Diagnosis of Coronary Artery Disease with Tl-201 SPECT in Patients with Left Bundle Branch Block: Importance of Alternative Interpretation Approaches for Left Anterior Descending Coronary Lesions

• Published in: Angiology 2001-02, Vol.52 (2), p.103-108
• Main Authors: Tandogan, Izzet, Yetkin, Ertan, Ileri, Mehmet, Ortapamuk, Hulya, Yanik, Ahmet, Çehreli, Sengul, Duru, Erdal
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Bundle-Branch Block - complications; Cardiovascular system; Coronary Angiography; Coronary Disease - complications; Coronary Disease - diagnostic imaging; Exercise Test; Female; Heart - diagnostic imaging; Heart Septal Defects - complications; Heart Septal Defects - diagnostic imaging; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Predictive Value of Tests; Radionuclide investigations; Sensitivity and Specificity; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tropical medicine
• ISSN: 0003-3197; 1940-1574
• DOI: 10.1177/000331970105200203

Left bundle branch block (LBBB) is a strong predictor of mortality in the presence of coronary artery disease (CAD). Noninvasive evaluation of CAD in these patients has some difficulties. Exercise-induced electrocardiographic ST segment changes are nondiagnostic, and several scinti graphic studies have reported false-positive anteroseptal and septal perfusion defects up to 80%. The authors aimed to assess the diagnostic accuracy of thallium-201 (Tl-201) exercise myocardial single photon emission computerized tomography (SPECT) in comparison with coronary angiog raphy (CAG) for detection of CAD in patients with LBBB. Seventy-seven consecutive patients suffering from chest pain with complete and permanent LBBB were included in the study. All patients (40 women, 37 men, mean age = 54 ±7 years) were studied with TI-201 exercise SPECT and coronary angiography. TI-201 exercise SPECT for diagnosis of left anterior descending (LAD) artery lesions was interpreted by using three different approaches: method A (conventional approach), method B (involvement of anterior and septal wall regardless of apical wall), and method C (apical approach: involvement of anterior septal and apical wall). Methods A and B gave a sensitivity of 100% each but a specificity of 47% and 56%, respectively. Although method C gave a higher value of specificity than that of methods A and B (98% vs 47% and 56%, respectively p < 0.05), the sensitivity of method C significantly decreased in respect to methods A and B (33% vs 100% p