Division of Cardiovascular Medicine, University of Miami Miller School of Medicine, 1600 NW 10th Avenue, Miami, FL 33136, USA.
J Nucl Cardiol. 2013 Aug;20(4):529-38. doi: 10.1007/s12350-013-9731-1. Epub 2013 May 24.
Previous studies have suggested that diabetic patients undergoing single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) are at greater risk for cardiac events than non-diabetic patients with both normal and abnormal imaging results. However, the impact of stress modality on outcomes in this patient group has not been examined.
The data on all patients undergoing exercise stress or vasodilator stress SPECT MPI from 1996 to 2005 were reviewed. After excluding patients based on our predefined criteria, we subcategorized the study population into diabetic patients and non-diabetic patients. Among the diabetic patients, we identified patients with known coronary artery disease (CAD) and no known CAD. All studies were interpreted using the 17-segment ASNC model. The presence, extent, and severity of perfusion defects were calculated using the summed stress score (SSS), and patients were classified into normal (SSS < 4), mildly abnormal (SSS 4-8), and moderate-severely abnormal (SSS > 8) categories. The annualized cardiac event rate including cardiac death and non-fatal myocardial infarction was calculated over a mean follow-up period of 2.4 ± 1.4 years with a maximum of 6 years.
The cardiac event rate was statistically significantly lower in diabetic patients undergoing exercise stress MPI when compared to the diabetic patients undergoing pharmacological stress MPI across all three perfusion categories (1.3% vs 3.4%, 2.3% vs 5.7%, 4.2% vs 10.7%, respectively). Diabetic patients with no known CAD, who underwent exercise stress MPI had significantly lower cardiac events across all three perfusion categories as compared to the remainder of the diabetic population. Ability to perform exercise stress test was the strongest multivariate predictor of favorable outcome, whereas ejection fraction < 50%, abnormal perfusion imaging on SPECT MPI, and increasing age stood out as independent predictors of adverse outcome in the diabetic patients. Within the abnormal perfusion category, the annualized cardiac event rate among patients undergoing exercise stress SPECT MPI was not statistically different between the diabetic and non-diabetic cohorts.
Diabetic patients undergoing exercise SPECT MPI have a significantly better prognosis than those undergoing pharmacological stress, more similar to patients without diabetes. In patients with diabetes exercise stress test MPI identifies low risk patients and provides precise risk stratification.
先前的研究表明，与正常和异常成像结果的非糖尿病患者相比，接受单光子发射计算机断层扫描（SPECT）心肌灌注成像（MPI）的糖尿病患者发生心脏事件的风险更高。然而，尚未检查该患者群体中应激方式对结局的影响。
回顾了 1996 年至 2005 年期间所有接受运动或血管扩张剂应激 SPECT MPI 的患者的数据。根据我们预先设定的标准排除患者后，将研究人群分为糖尿病患者和非糖尿病患者。在糖尿病患者中，我们确定了已知冠心病（CAD）和无已知 CAD 的患者。所有研究均采用 17 节段 ASNC 模型进行解读。通过总和应激评分（SSS）计算灌注缺陷的存在、程度和严重程度，并将患者分为正常（SSS<4）、轻度异常（SSS 4-8）和中度严重异常（SSS>8）类别。在平均 2.4±1.4 年（最长 6 年）的随访期间计算包括心脏死亡和非致死性心肌梗死在内的年化心脏事件发生率。
在所有三个灌注类别中，与接受药物应激 MPI 的糖尿病患者相比，接受运动应激 MPI 的糖尿病患者的心脏事件发生率均具有统计学意义上的降低（分别为 1.3%比 3.4%、2.3%比 5.7%、4.2%比 10.7%）。在所有三个灌注类别中，无已知 CAD 的接受运动应激 MPI 的糖尿病患者的心脏事件发生率明显低于其余糖尿病患者。进行运动应激试验的能力是良好预后的最强多变量预测因素，而射血分数<50%、SPECT MPI 异常灌注成像和年龄增加是糖尿病患者不良预后的独立预测因素。在异常灌注类别中，接受运动 SPECT MPI 的糖尿病和非糖尿病患者的年化心脏事件发生率无统计学差异。
与接受药物应激相比，接受运动 SPECT MPI 的糖尿病患者的预后明显更好，与无糖尿病患者更相似。在糖尿病患者中，运动应激试验 MPI 可识别低风险患者并提供精确的风险分层。
