Prospective Investigation of Pulmonary Embolism Dx III

描述（由申请人提供）： 肺栓塞诊断的前瞻性研究III（PIOPED III）是一项多中心前瞻性研究，旨在确定临床疑似急性肺栓塞（PE）患者中肺动脉钆增强磁共振血管造影（Gd-MRA）联合大腿静脉磁共振静脉造影（MRV）的诊断准确性。这是行政中心的建议，它包含了PIOPED III的科学部分。Gd-MRA单独和与MRV联合的诊断准确性将表示为阳性和阴性试验的灵敏度、特异性和似然比。研究设计是一项前瞻性研究，纳入了标准化的纳入/排除标准，完全确定患者特征和结局，统一的诊断标准，以及无偏倚的成对中心影像学检查读数。在两年的时间内，将在7个临床中心招募1256例疑似急性PE患者。复合参考标准品将用于诊断VTE并排除PE。预计将有314名患者患有急性VTE，他们将接受Gd-MRA/MRV。预计将有942例患者显示无PE。从该组中随机选择314例患者进行指标检查，Gd-MRA/MRV。这项建议的优点是：1）PE问题在因诊断不足而死亡和因过度诊断而导致大出血方面的重要性，2）诊断PE的新技术的潜在适用性，3）以前在PE成功研究中合作过的强大研究团队，4）与先前证明的用于评估PE诊断测试的方案并行的方案。

DESCRIPTION (provided by applicant): The Prospective Investigation of Pulmonary Embolism Diagnosis III (PIOPED III) is a multicenter prospective investigation designed to determine the diagnostic accuracy of gadolinium enhanced magnetic resonance angiography of the pulmonary arteries (Gd-MRA) in combination with magnetic resonance venography of the veins of the thighs (MRV) in patients with clinically suspected acute pulmonary embolism (PE). This is the proposal for the Administrative Center, and it contains the scientific portion of PIOPED III. The diagnostic accuracy of Gd-MRA alone and in combination with MRV will be expressed as sensitivity, specificity, and likelihood ratio for positive and negative tests. The study design is a prospective study of consecutive patients incorporating standardized inclusion/exclusion criteria, complete ascertainment of patient characteristics and outcomes, uniform diagnostic criteria, and unbiased paired central readings of imaging studies. Over a period of two years, 1256 patients with suspected acute PE will be recruited at 7 clinical centers. Composite reference standards will be used to diagnose VTE and exclude PE. It is expected that 314 patients will have acute VTE and they will undergo Gd-MRA/MRV. It is expected that 942 patients will be shown not to have PE. From among this group, 314 patients will be randomly selected for the index test, Gd-MRA/MRV. The strengths of this proposal are: 1) the importance of the problem of PE in terms of lives lost from under diagnosis and major bleeding from over diagnosis, 2) the potential applicability of a new technology for the diagnosis of PE, 3) a strong investigative team that has collaborated previously in successful research in PE, 4) a protocol that parallels previously proven protocols for the evaluation of a diagnostic test for PE.