Relationship between QT/QS2 ratio and angiographic severity of coronary heart disease.
The relationship between QT/QS2 ratio and angiographic severity of coronary heart disease (CHD) was determined in 99 patients who underwent coronary arteriography because of chest pain. Sixteen control patients with normal coronary arteriograms and normal left ventricular function and 83 patients with angiographic evidence of CHD were studied. QT/QS2 ratio and systolic time intervals were calculated from poligraphic recordings taken at rest. In control subjects QT/QS2 ratio was significantly shorter (0.91 +/- 0.04) than in patients with double (0.95 +/- 0.07; p less than 0.05 versus control subjects) and triple vessel coronary artery disease (0.95 +/- 0.05; p less than 0.05 versus control subjects). QT/QS2 ratio was significantly higher (p less than 0.01) in patients with 3 areas or more of left ventricular abnormal wall motion (LV AWM) (0.98 +/- 0.05) than in patients with none (0.92 +/- 0.06) or just 1-2 areas (0.93 +/- 0.06) of LV AWM. Multiple regression analysis revealed no relation between the number of coronary stenoses and QT/QS2 (t = 0.86; p = NS), while a relation was identified between the number of asynergic segments and QT/QS2 (t = 1.99; p less than 0.05). A significant correlation was found between QT/QS2 and PEP/LVET (r = 0.39; p less than 0.001). Setting the upper normal limit at 2 standard deviations from the mean of control subjects (QT/QS2 = 0.99), QT/QS2 criterion yielded a 30% sensitivity, a 94% specificity and a 96% predictive accuracy in diagnosing CHD. We conclude that in CHD patients QT/QS2 ratio is influenced by the extension of LV AWM. Although a low sensitivity may limit its use, a QT/QS2 value higher than 0.99 in a patient with chest pain strongly suggests CHD and thus this criterion may be diagnostically useful.
Cuomo
S
S
Servizio di Cardiologia, Centro Traumatologico Ortopedico, Napoli.
Acanfora
D
D
Papa
M
M
Covelluzzi
F
F
Tedeschi
C
C
Furgi
G
G
Rengo
F
F
De Caprio
L
L
D000328:Adult; D000368:Aged; D000792:Angiography; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D003327:Coronary Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged