Shaffer P B, Magorien D J, Olsen J O, Bashore T M
Department of Radiology, Ohio State University, Columbus.
Nucl Med Commun. 1987 Jun;8(6):417-29. doi: 10.1097/00006231-198706000-00004.
Ventricular filling rates derived from radionuclide angiographic (RNA) time-activity curves are commonly expressed as normalized values. The assumption that normalized filling rates have a relationship to the actual filling rates was tested. RNA and contrast angiography were performed within 20 min of one another in 21 patients with widely disparate volumes. The RNA time-activity curve was converted from counts to milliliters by equating the contrast angiography derived end diastolic volume to the end diastolic count rate determined by RNA. Peak filling rates were normalized to end diastolic volume (EDV), stroke volume (SV, and peak ejection rate (ER). No significant correlation between the normalized filling rates and the true filling rate was found. Significant correlations were found between the EDV normalized filling rate and the EDV (r = -0.70) and the ejection fraction (r = 0.89). Normalized filling rates are dependent upon the normalizing variable and are not a pure measure of ventricular filling rates. As the technique of gated radionuclide angiography has matured, it has become apparent that there is more information in the time-activity curve than just the ejection fraction. The emptying rates, filling rates, time to peak emptying, and time to peak filling are parameters that are also available from the time-activity curve. Several authors have used this information to quantitate ventricular ejection and filling rates [1-6]. Since the contrast angiography literature would indicate that in some disease states ventricular filling is impaired [7,8], attempts have been made to identify impaired filling rates by radionuclide techniques. Using this method, decreased normalized filling rates have been found in groups of patients with coronary artery disease and it has been suggested that the observed decrease is due to impairment of active relaxation and/or to reduced compliance [2,3,5,6]. It has even been suggested that the decrease seen in the normalized filling rates may be a reflection of ischemia in the resting patient [6]. While these RNA derived parameters have been normalized to end diastolic volume by most authors, normalization to stroke volume and maximum ejection rate have also been suggested [9,10]. A possible rationale for normalization is that the activity measured over the ventricle is dependent upon many factors, including radionuclide dose, attenuation from the patient's chest wall, the specific type of collimator used, thickness of the crystal, and the window width.(ABSTRACT TRUNCATED AT 400 WORDS)
从放射性核素血管造影（RNA）时间-活性曲线得出的心室充盈率通常表示为标准化值。对标准化充盈率与实际充盈率之间存在关联这一假设进行了检验。对21例心室容积差异很大的患者在20分钟内先后进行了RNA和造影血管造影检查。通过使造影血管造影得出的舒张末期容积与RNA测定的舒张末期计数率相等，将RNA时间-活性曲线从计数转换为毫升。将峰值充盈率标准化为舒张末期容积（EDV）、每搏量（SV）和峰值射血率（ER）。未发现标准化充盈率与真实充盈率之间存在显著相关性。发现EDV标准化充盈率与EDV（r = -0.70）和射血分数（r = 0.89）之间存在显著相关性。标准化充盈率取决于标准化变量，并非心室充盈率的纯粹度量。随着门控放射性核素血管造影技术的成熟，越来越明显的是，时间-活性曲线中包含的信息不止射血分数。排空率、充盈率、达到峰值排空的时间和达到峰值充盈的时间也是可从时间-活性曲线获得的参数。几位作者已利用这些信息来定量心室射血和充盈率[1-6]。由于造影血管造影文献表明在某些疾病状态下心室充盈受损[7,8]，因此已尝试通过放射性核素技术识别受损的充盈率。使用这种方法，在冠心病患者组中发现标准化充盈率降低，有人认为观察到的降低是由于主动舒张功能受损和/或顺应性降低所致[2,3,5,6]。甚至有人提出，标准化充盈率的降低可能反映了静息患者的缺血情况[6]。虽然大多数作者已将这些从RNA得出的参数标准化为舒张末期容积，但也有人建议将其标准化为每搏量和最大射血率[9,10]。标准化的一个可能理由是，在心室上测量的活性取决于许多因素，包括放射性核素剂量、来自患者胸壁的衰减、所用准直器的具体类型、晶体厚度和窗宽。（摘要截断于400字）
