Comparison of myocardial contrast echocardiography with SPECT in the evaluation of coronary artery disease in asymptomatic patients with LBBB.
OBJECTIVE
The non-invasive assessment of coronary artery disease (CAD) in patients with left bundle branch block (LBBB) is troublesome. In this study, we investigated the diagnostic accuracy of myocardial contrast echocardiography (MCE) with adenosine to detect CAD in asymptomatic patients with LBBB, and we compared it with single photon emission computed tomography (SPECT) with adenosine.


METHODS
Forty-seven patients with LBBB, and no previously documented CAD, initially underwent SPECT imaging and 1-3 days later MCE. Coronary arteriography was performed within 1 week from the latter procedure.


RESULTS
The overall sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy, and kappa index of concordance of SPECT were 73%, 72%, 44%, 90%, 72%, and 0.37+/-0.13, respectively, whereas those of MCE were 91%, 92%, 77%, 97%, 92%, and 0.77+/-0.1, respectively (p<0.05 for all comparisons). Significant CAD was present in 11 patients (23%). Left anterior descending coronary artery was involved in 8 patients, left circumflex artery in 2 patients, and right coronary artery in 4 patients. Concerning the left anterior descending artery disease detection, SPECT had a sensitivity of 75%, a specificity of 79%, a positive predictive value of 43%, a negative predictive value of 94%, and a diagnostic accuracy of 79%. The respective values of MCE were 100% for all of the above variables.


CONCLUSIONS
MCE with adenosine has a higher global diagnostic accuracy compared to SPECT for the detection of CAD in patients with LBBB, mainly due to the poor specificity of SPECT concerning perfusion defects detection in the left anterior descending artery territory.
Karavidas
Apostolos I
AI
Department of Cardiology, Athens General Hospital, Greece.
Matsakas
Evangellos P
EP
Lazaros
George A
GA
Brestas
Paris S
PS
Avramidis
Dimitrios A
DA
Zacharoulis
Achilleas Ap
AA
Fotiadis
Ioannis N
IN
Korres
Dimitrios A
DA
Zacharoulis
Apostolos Ach
AA
D000241:Adenosine; D002037:Bundle-Branch Block / Q000209:etiology*; D003287:Contrast Media; D003327:Coronary Disease / Q000150:complications / Q000000981:diagnostic imaging*; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011134:Polysaccharides; D012372:ROC Curve; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents
D003287:Contrast Media; D011134:Polysaccharides; D014665:Vasodilator Agents; C059891:SHU 508; D000241:Adenosine