Dipyridamole body surface potential mapping: noninvasive differentiation of syndrome X from coronary artery disease.
Up to 20% to 30% of patients with angina and abnormal stress test have normal coronary arteries at angiography or syndrome X (Sy X). We tested whether body surface potential mapping (BSPM) with intravenous dipyridamole could differentiate patients with Sy X from patients with coronary artery disease (CAD). We compared the effects of intravenous dipyridamole (0.28 mg/kg over 4 min) on BSPM in 17 healthy volunteers (controls) and in 2 groups of patients with angina and abnormal ergometric tests who were referred for angiography: 27 patients with obstructive disease (> or =70% diameter stenosis) in the CAD group, and 17 patients with Sy X. Control subjects were easily differentiated from patients with CAD or Sy X by markedly smaller baseline BSPM DeltaST-T < or = LSD departure areas (P <.001), but the Sy X and CAD groups had similar ST-T departure areas. The average potential integral difference after dipyridamole (APID) differentiated Sy X and CAD patients: the mean APID increased in patients with Sy X and trended negative in the CAD group. The APID(20%-40%) (integrated over 20% to 40% of the ST-T interval) mean value was 0.59 +/- 0.67 microVs in the Sy X group and -0.18 +/- 0.59 microVs in the CAD group (P <.01). At a threshold APID(20%-40%) > 0.17 microVs, the sensitivity and specificity for Sy X was 71% and 78%, respectively; the area under the receiver operating characteristic curve was 0.79 (95% CI 0.64, 0.93). Dipyridamole BSPM is a promising noninvasive diagnostic modality to differentiate patients with Sy X from those with CAD.
Boudik
Frantisek
F
second Department of Internal Medicine, Charles University Hospital, Prague, Czech Republic. fboud@lfl.cuni.cz
Anger
Zdenk
Z
Aschermann
Michael
M
Vojácek
Jan
J
Tomecková
Marie
M
D018780:Body Surface Potential Mapping / Q000187:drug effects*; D017023:Coronary Angiography; D003327:Coronary Disease / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004176:Dipyridamole / Q000008:administration & dosage / Q000494:pharmacology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D017566:Microvascular Angina / Q000175:diagnosis*; D008875:Middle Aged; D012680:Sensitivity and Specificity
D004176:Dipyridamole