운동 부하 심전도 검사에서 하벽부 유도의 진단적 유용성에 관한 고찰

Objectives: Many exercise test trials in patients with angina pectoris have demonstrated that precordial lead V5 is the best single lead as a marker for coronary artery disease. And the diagnostic value of ST segment depressions in the inferior leads is questionable. Methods: 170 patients had a standard exercise test and underwent diagnostic coronary angiography within 1 month of the exercise test. 71 patients had coronary artery disease (stenosis≥50%), whereas 99 patients did not. Sensitivity, specificity, and positive predictive value of each lead and lead groups were calculated to find the reliable leads. And the receiver operating characteristics(ROC) curves were used to compare the reliability between lead II and U5. Results: Multiple lead system had higher sensitivity than that of single lead system, but the specificity is decreased. Comparing the sensitivity and the specificity among each lead, lead V5 is the best single lead. ROC curve analysis also revealed that lead V5 (area=0.725) was markedly superior to lead II(area = 0.635) over multiple cut points(Z = 5.417; p < 0.01). However, the area under the lead II curve(0.635) was greater than 0.5(Z=3.05; p