Significance of dipyridamole-induced transient dilation of the left ventricle during thallium-201 scintigraphy in suspected coronary artery disease.
The occurrence and significance of transient dilation of the left ventricle during dipyridamole stress-redistribution thallium-201 scintigraphy was studied in 73 patients who underwent both dipyridamole thallium-201 study and coronary angiography. Transient dilation ratio was calculated from planar anterior images by dividing the computer-derived left ventricular area on the initial image by that of the 4-hour image. In 11 patients with normal coronary arteriograms or less than 50% coronary stenosis, the transient dilation ratio was 0.98 +/- 0.046. An abnormal transient dilation ratio was defined as greater than or equal to 1.12, representing greater than or equal to 3 standard deviations above the mean normal value. When the 15 patients with an abnormal ratio were compared with the 58 with a normal ratio, the former group had a significantly higher frequency of 3 critical (greater than or equal to 90%) coronary stenoses (33 vs 5%), higher prevalence of collaterals (67 vs 24%), more extensive myocardial reversible defects by planar (71 vs 10%) or by single-photon emission computed tomography (87.5 vs 35%) imaging and a higher incidence of dipyridamole-induced anginal chest pain (53 vs 22%). No significant difference between the 2 groups was noted with respect to age, gender, prior myocardial infarction, single or double critical coronary stenosis, dipyridamole-induced ischemic electrocardiographic response and increased lung uptake. An abnormal transient dilation ratio of greater than or equal to 1.12 was a specific marker of multivessel (87%) or 3-vessel (85%) critical coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)
Chouraqui
P
P
Department of Medicine (Division of Cardiology), Cedars-Sinai Medical Center, Los Angeles, California.
Rodrigues
E A
EA
Berman
D S
DS
Maddahi
J
J
D000368:Aged; D000792:Angiography; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D004108:Dilatation, Pathologic / Q000139:chemically induced; D004176:Dipyridamole; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000187:drug effects*; D006801:Humans; D008297:Male; D013794:Thallium Radioisotopes; D013997:Time Factors; D014055:Tomography, Emission-Computed / Q000379:methods
D013794:Thallium Radioisotopes; D004176:Dipyridamole