Galassi A R, Azzarelli S, Lupo L, Mammana C, Foti R, Tamburino C, Musumeci S, Giuffrida G
Institute of Cardiology, Ferrarotto Hospital, Italy.
J Nucl Cardiol. 2000 Nov-Dec;7(6):575-83. doi: 10.1067/mnc.2000.108731.
The separation of patients with suspected or known coronary artery disease into low- and high-risk subgroups by means of noninvasive testing is highly relevant in the selection of patients who require further diagnostic or therapeutic investigation. We evaluated whether exercise electrocardiographic variables during exercise testing might be a means of predicting the severity of myocardial ischemia as assessed with myocardial scintigraphy.
We retrospectively reviewed 816 consecutive patients (mean age, 57+/-10 years) who underwent exercise technetium-99m tetrofosmin single photon emission computed tomography (SPECT) for the assessment of suspected or known coronary artery disease. Eight independent significant predictors of the extent and severity of reversible perfusion defects (ischemic perfusion score), which when integrated in a diagnostic algorithm satisfactorily discriminated patients with no reversible perfusion defects (sensitivity, 75%; specificity, 80%) and patients with severe impaired myocardial perfusion (> or =11 ischemic perfusion score; sensitivity, 77%; specificity, 82%), were identified by means of stepwise discriminant analysis. However, patients with mildly to moderately impaired myocardial perfusion (> or =21 but <11 ischemic perfusion score) were poorly discriminated (sensitivity, 50%; specificity, 78%). The set of variables that were significant (P<.0001) for prediction included sex, myocardial infarction, exercise angina, the maximal amount of ST segment depression, rate-pressure product threshold criteria, slope of ST segment depression, ST/heart rate index, and peak exercise heart rate.
The results of the use of clinical and electrocardiographic exercise variables satisfactorily agrees with the results from scintigraphy only for patients with no reversible perfusion defects and with severely impaired myocardial perfusion. However, it fails as an approach with universal applicability.
通过无创检测将疑似或已知冠心病患者分为低风险和高风险亚组，对于选择需要进一步诊断或治疗性检查的患者具有高度相关性。我们评估了运动试验期间的运动心电图变量是否可能是预测心肌灌注显像所评估的心肌缺血严重程度的一种方法。
我们回顾性分析了连续816例患者（平均年龄57±10岁），这些患者接受了运动锝-99m替曲膦单光子发射计算机断层扫描（SPECT）以评估疑似或已知的冠心病。通过逐步判别分析确定了可逆性灌注缺损范围和严重程度（缺血灌注评分）的8个独立显著预测因素，将这些因素整合到诊断算法中可令人满意地区分无可逆性灌注缺损的患者（敏感性75%；特异性80%）和心肌灌注严重受损的患者（缺血灌注评分≥11；敏感性77%；特异性82%）。然而，心肌灌注轻度至中度受损的患者（缺血灌注评分≥2但<11）区分效果较差（敏感性50%；特异性78%）。对预测有显著意义（P<0.0001）的变量集包括性别、心肌梗死、运动性心绞痛、ST段压低的最大量、心率血压乘积阈值标准、ST段压低斜率、ST/心率指数和运动峰值心率。
仅对于无可逆性灌注缺损和心肌灌注严重受损的患者，使用临床和运动心电图变量的结果与灌注显像结果令人满意地相符。然而，它作为一种具有普遍适用性的方法并不成功。
