Samuels B, Kiat H, Friedman J D, Berman D S
Department of Imaging, Cedars-Sinai Medical Center, Los Angeles 90048.
J Am Coll Cardiol. 1995 Jan;25(1):99-106. doi: 10.1016/0735-1097(94)00317-j.
This study assessed the safety and diagnostic accuracy of adenosine stress myocardial perfusion scintigraphy for the detection of coronary artery disease using single-photon emission computed tomography (SPECT) in patients with significant aortic stenosis.
Exercise cardiac stress testing in patients with significant aortic stenosis is generally avoided because of concerns for safety. In addition, those studies that have analyzed the utility of exercise testing both with and without myocardial thallium-201 scintigraphy for the diagnosis of coronary artery disease have yielded low specificity. Currently, no safe and accurate means exists to noninvasively assess the presence, extent and severity of coronary artery disease in patients with significant aortic stenosis.
The study included 35 patients with moderate to severe aortic stenosis (mean [+/- SD] aortic valve area 0.84 +/- 0.16 cm2, range 0.5 to 1.2; mean maximal instantaneous aortic valve gradient 44.4 +/- 15.9 mm Hg, range 20 to 84). All patients underwent a 6-min adenosine infusion (140 micrograms/kg body weight per min) protocol and either separate acquisition rest thallium-201/stress technetium-99m sestamibi or stress and 4-h redistribution thallium-201 SPECT: Visual 20-segment SPECT analysis used a standard five-point scoring system from 0 (normal tracer uptake) to 4 (absent uptake). The SPECT results were considered abnormal if more than two segments had a stress score > or = 2. Hemodynamic, electrocardiographic and clinical responses were compared with those in a reference group of 100 consecutive age-matched patients undergoing adenosine SPECT who did not have aortic stenosis.
Hemodynamic responses during adenosine stress testing between the study and control patients demonstrated no significant difference in the net change in systolic blood pressure (18% of baseline vs. 14%, patients with aortic stenosis vs. control subjects), heart rate (21% vs. 19%), rate-pressure product (0% vs. 2%) or incidence of chest pain (23% vs. 35%) or transient second-(9% vs. 9%) or third-degree atrioventricular block (3% vs. 1%). In the 20 patients who had coronary angiography, sensitivity for detection of coronary artery disease was 92% (12 of 13) and specificity was 71% (5 of 7).
In this preliminary study, adenosine was found to be well tolerated and diagnostically accurate in patients with moderate to severe aortic stenosis.
本研究使用单光子发射计算机断层扫描（SPECT）评估腺苷负荷心肌灌注显像在重度主动脉瓣狭窄患者中检测冠状动脉疾病的安全性和诊断准确性。
由于安全性问题，通常避免对重度主动脉瓣狭窄患者进行运动心脏负荷试验。此外，那些分析了有无心肌201铊显像的运动试验对冠状动脉疾病诊断效用的研究，其特异性较低。目前，尚无安全准确的方法可用于无创评估重度主动脉瓣狭窄患者冠状动脉疾病的存在、范围和严重程度。
该研究纳入35例中重度主动脉瓣狭窄患者（平均[±标准差]主动脉瓣面积0.84±0.16cm²，范围0.5至1.2；平均最大瞬间主动脉瓣压差44.4±15.9mmHg，范围20至84）。所有患者均接受6分钟的腺苷输注（140微克/千克体重/分钟）方案，并进行单独的静息201铊/负荷99m锝甲氧基异丁基异腈采集或负荷及4小时再分布201铊SPECT：视觉20节段SPECT分析采用从0（正常示踪剂摄取）到4（无摄取）的标准五点评分系统。如果超过两个节段的负荷评分≥2，则SPECT结果被视为异常。将血流动力学、心电图和临床反应与100例连续的年龄匹配的接受腺苷SPECT但无主动脉瓣狭窄的患者参考组进行比较。
研究患者和对照患者在腺苷负荷试验期间的血流动力学反应显示，收缩压净变化（主动脉瓣狭窄患者为基线的18%，对照受试者为14%）、心率（21%对19%）、率压乘积（0%对2%）或胸痛发生率（23%对35%）或短暂二度（9%对9%）或三度房室传导阻滞（3%对1%）无显著差异。在20例行冠状动脉造影的患者中，检测冠状动脉疾病的敏感性为92%（13例中的12例），特异性为71%（7例中的5例）。
在这项初步研究中，发现腺苷在中重度主动脉瓣狭窄患者中耐受性良好且诊断准确。
