Novel Cardiac MRI techniques for the diagnosis of coronary artery disease compared to PET imaging and Invasive Coronary Angiography.

在英国，冠状动脉疾病(CAD)是第二大最常见的死亡原因，及早识别患有CAD的患者非常重要，以便在心脏病发作之前开始预防。用于检测CAD的测试范围很广。NHS常规使用冠状动脉造影术，如果没有额外的血流测量，我们就不知道CAD有多重要。心脏扫描可用于检测重要的CAD，包括使用放射性染料、超声波或心脏磁共振(CMR)的扫描，这些扫描只需在计算机控制台上查看图像即可解释。这种视觉解释通常是准确的，但即使是训练有素的个人，扫描记者的解释也可能不同，特别是在存在如此广泛的CAD以至于测试可能看起来正常的情况下。我们可以用心脏扫描来测量心脏的血流量，最好的方法是正电子发射断层扫描(PET)。在识别心脏病方面，这比目视检查更好，可以帮助预测心脏病发作和其他健康危害的风险，并帮助医生决定哪些患者需要接受心脏手术治疗。不幸的是，PET扫描价格昂贵(每次扫描超过2000 GB)，不能广泛使用，而且使用潜在的有害电离辐射。CMR可以用来测量心脏的血流。与PET相比，它有一个主要优势，因为它更便宜(约500 GB)，更广泛地获得，并且由于没有使用有害辐射而更安全。在之前的研究中(最大的一项研究是在伦敦国王学院进行的)，对比了PET和CMR的血流测量结果，发现两者相似，但并不完全一致。这项研究有一些重要的局限性，因为患者在不同的日期和不同的分析中使用不同的CMR和PET扫描仪进行扫描。因此，目前还没有关于PET和CMR血流测量的决定性比较。先进的技术-我们很荣幸拥有一台‘混合式PET-MR扫描仪’，这是英国唯一的第二台，能够同时进行PET和CMR扫描。这款扫描仪允许我们与PET和CMR在完全相同的时间进行心脏血流测量，因此可以真正进行测试比较。这将帮助我们更确定地确定CMR在测量心脏血流方面是否与PET一样好。-我们已经开发出一种新的方法来测量心脏的血流量，这种方法在动物和血流模型研究中非常准确，但我们需要在人体上进行测试。-使用CMR测量血流量既麻烦又耗时，即使是专家也可能需要几个小时。我们已经开发了一种自动化软件来执行这一任务，该软件可以用于NHS.AIMI的常规临床诊断。AIMI的目的是测试CMR是否可以成为一种更便宜、更广泛和更安全的PET替代品。如果证明具有可比性，自动化的CMR工具可以很容易地在英国各地转化为临床实践，以提高对CAD的诊断。我将使用一种新的混合PET-MR扫描仪和新的CMR技术在心脏病患者中比较PET和CMR测量的血流量。我们将比较新型CMR的血流测量结果与冠状动脉造影术的结果。方法：10名无心脏病的健康志愿者接受正电子发射计算机断层扫描(PET-MR)，同时用正电子发射计算机断层扫描(PET)和磁共振心动图(CMR)测量血流。这将使我们能够在人体上测试这种方法。-77名计划进行血管造影术的患者将接受PET-MR心脏扫描。我们将把血流测量与CMR、PET以及CAD的存在与冠状动脉造影进行比较。我们希望对心脏的血流有更好的了解，并测试这种CMR工具是否与PET和血管造影一样好。这将对患者有所帮助，因为CMR是安全、非侵入性的，而且不使用辐射。这一工具可以通过指导医生对哪些患者需要药物、支架或心脏手术来更好地治疗患者。

Coronary artery disease (CAD) is the second most common cause of death in the UK and it is very important to identify patients who have CAD early so that prevention can be started before a heart attack occurs. A wide range of tests are used to detect CAD. Coronary angiography is routinely used in the NHS, and without extra flow measurements, we do not know how important CAD is. Heart scans can be used to detect important CAD including a scan that uses radioactive dye, ultrasound or cardiac MRI (CMR) which are interpreted by simply looking at images on a computer console. This visual interpretation is generally accurate but even with well trained individuals, scan reporters can differ in their interpretation especially in cases where there is such widespread CAD that the test may be appear normal. We can measure the heart's blood flow with heart scans and the best method to do this is with Positron Emission Tomography (PET). This is better than visual inspection in identifying heart disease, can help with predicting the risk of a heart attack and other health hazards and help doctors decide which patients to treat with heart surgery. Unfortunately PET scanning is expensive (over £2,000 per scan), not available widely and uses potential harmful ionising radiation.CMR can be used to measure the heart's blood flow. It has a major advantage over PET because it is much cheaper (around £500), more widely available and is safer as no harmful radiation is used. In previous research studies (the largest one performed at King's College London), blood flow measurements with PET and CMR were compared and found to be similar but not to agree perfectly. This study had some important limitations, as patients were scanned using separate CMR and PET scanners, on different days and separate analysis. Therefore, there has yet to be a conclusive comparison of PET and CMR blood flow measurements.ADVANCES IN TECHNOLOGY- We are privileged to have a 'hybrid PET-MR scanner', only the second one in the UK, which is able to perform PET and CMR scans at the same time. This scanner allows us to perform heart blood flow measurements at exactly the same time with PET and CMR and therefore allows a true head on comparison of the tests. This will help us to determine with more certainty if CMR is as good as PET for measuring the heart's blood flow. - We have developed a new method to measure the heart's blood flow which is very accurate in animal and flow model studies but we need to test this in humans.- Measuring blood flow is cumbersome and time-consuming with CMR and can take several hours even for an expert. We have developed an automated software to perform this which may be used for routine clinical diagnosis at point of care in the NHS.AIMI aim to test if CMR can be a cheaper, more widely available and safer alternative to PET. If proven to be comparable, automated CMR tools can be readily translated to clinical practice across the UK to enhance diagnosis of CAD. I will compare blood flow measured with PET and CMR using a novel hybrid PET-MR scanner and novel CMR techniques in patients with heart disease. We will compare blood flow measurements with novel CMR with findings with coronary angiography. METHODS-10 healthy volunteers without heart disease will undergo a PET-MR scan to measure blood flow with PET and CMR at the same time. This will allow us to test the method in humans.-77 patients who are scheduled for an angiogram will have a PET-MR scan of their heart . We will compare blood flow measurements with CMR, PET and presence of CAD with coronary angiography.We hope to get a better understanding of the heart's blood flow and test if this CMR tool is as good as PET and angiography. This will be helpful to patients as CMR is safe, non-invasive and does not use radiation. This tool may help doctors treat patients better by guiding doctors on which patients needs medications, stents or heart surgery.