Transvaginal Probe for Fetal Magnetocardiography

描述(申请人提供)：目前，胎儿心磁图(FMCG)的检测在胎龄小于15周时是不可能的，在小于20-24周的孕期是不可靠的，肥胖症患者即使在最后三个月也经常很难检测到。这在评估患有高危心脏疾病的患者中的胎儿心脏状况以及一般的产前护理管理方面提出了一系列问题。经阴道胎儿超声心动图检查可以更好地分辨近至13周的极小的胎儿解剖结构，从而增强了胎儿的成像能力，但不能准确测量胎儿的心律和传导障碍。为了应对这一挑战，FMCG的开创性工作展示了基于SQUD的胎儿MCG系统的独特功能，包括QRS和QT间期测量、准确的心跳分析、精确的心律失常记录和详细的胎儿心率趋势分析。该提案的目的是开发一种经阴道鱿鱼快速心电描记系统，用于直接记录胎龄小于15周的胎儿心脏活动，以及胎儿大脑的电磁活动。这将有助于早期检测患有危及生命的心律失常、获得性心力衰竭和结构性先天性心脏病的胎儿的宫内临床情况。与传统的胎儿MCG系统不同，传统的胎儿MCG系统体积庞大，需要安装在沉重而昂贵的磁屏蔽室中，新系统的设计将紧凑而轻便，适合在临床环境中使用。在这项第二阶段的工作中，我们确定了主要的技术挑战，并将系统地解决这些挑战，为顺利过渡到第三阶段的人体测试和未来的临床操作铺平道路。一期仪器将进行改装，纳入矢量测量和噪声消除通道。将进行动物实验，以证明改进的第一阶段仪器在活体中的可行性。在数据分析中，将对新的降噪算法进行集成和测试。这些研究结果将指导设计和建造易于适应OBGYN临床的轻质磁屏蔽；带有参考阵列的矢量传感器探头，可以适应不同妊娠阶段的胎儿发育；安全舒适的患者椅和探头架，以简化测试程序。将进行一系列测试，以获得探测器在模拟机械和低温故障时的风险水平。该项目的成功完成将带来有史以来第一个能够从怀孕早期提供准确记录的胎儿心脏病学诊断工具。它提供了识别胎儿心律失常和其他心脏疾病的重要能力。此外，它将极大地促进关于胎儿心脏和大脑发育的科学知识，这可以导致更好的产前护理和潜在的遗传疾病治疗。1 公共卫生相关性：这项建议旨在开发一种紧凑、非侵入性的经阴道鱿鱼磁心图(FMCG)系统，用于独特的早期监测胎儿心律状况。经阴道超声证实，经阴道放置是优化肥胖患者和妊娠早期信噪比的最有效的微创方法。这种新仪器将是世界上第一台能够可靠地表征患有危及生命的心律失常、获得性心力衰竭和结构性先天性心脏病的胎儿的传导模式和宫内临床情况的仪器。此外，它对胎儿脑磁图(FMEG)领域的影响可能更大，因为到目前为止，对人类胎儿大脑功能的宫内评估是不可能的。1

DESCRIPTION (provided by applicant): Currently the detection of fetal magnetocardiogram (fMCG) is not possible at gestational ages earlier than 15 weeks, is unreliable at gestations less than 20-24 weeks, and is often difficult in obese patients even in the last trimester. This presents a series problem in the assessment of fetal heart conditions in patients with high- risk cardiac conditions in specific, and in prenatal care management in general. Transvaginal approach for fetal echocardiography has enhanced fetal imaging by allowing better resolution of extremely small fetal anatomy at close range down to about 13 weeks, but cannot precisely measure fetal heart rhythm and conduction disorders. To answer this challenge, pioneering work on fMCG has demonstrated the unique capabilities of SQUID-based fetal MCG system, including QRS and QT interval measurements, accurate beat- to-beat analysis, precise arrhythmia recording, and detailed fetal heart rate trend analysis. The objective of proposal is to develop a transvaginal SQUID fMCG system for direct recording of fetal cardiac activities at gestational ages younger 15 weeks, and in addition fetal brain electromagnetic activity. This will facilitate early detections of intrauterine clinical condition of fetuses with life-threatening arrhythmias, acquired heart failure, and structural congenital heart disease. Unlike the conventional fetal MCG system, which is bulky and requires to be installed in a heavy and costly magnetic shielded room, the new system will be designed to be compact and light, suitable for use in clinical settings. In this Phase II work we have identified major technical challenges, and will address them systematically to pave way for smooth transition to human testing in Phase III and to future clinical operations. The Phase I instrument will be modified to incorporate vector measurement and noise cancellation channels. The animal tests will be conducted to demonstrate the feasibility of the improved Phase I instrument in live objects. In data analysis new noise reduction algorithm will be integrated and tested. Results of these studies will guide the design and construction of light weight magnetic shielding that is easily adaptive to OBGYN clinics; vector sensor probe with reference array that can accommodate development of fetus at different pregnancy stages; safe and comfortable patient chair and probe gantry to streamline test procedures. A series of tests will be carried out to access risk level in simulated mechanical and cryogenic failures of the probe. Successful completion of this program will lead to the first-ever diagnostic tool for fetal cardiology that is capable of providing accurate recording from early pregnancy stages. It offers the significant ability to identify fetal arrhythmias and other cardiac disorders. In addition, it will greatly advance scientific knowledge on both fetal heart and brain development, which can lead to better prenatal care and potential treatments for genetic disorders. 1 PUBLIC HEALTH RELEVANCE: This proposal aims to develop a compact, noninvasive transvaginal SQUID-based magnetocardiography (fMCG) system for unique early monitoring of fetal heart rhythm conditions. The transvaginal placement is the most effective minimally invasive method for optimizing the signal-to-noise ratio in obese patients and in early pregnancy, as has been demonstrated with transvaginal ultrasound. The new instrument will be a world's first in its capability to reliably characterize the conduction patterns and intrauterine clinical condition of fetuses with life-threatening arrhythmias, acquired heart failure, and structural congenital heart disease. In addition, its impact on the field of fetal Magnetoencephalography (fMEG) could be even greater since intrauterine evaluation of human fetal brain function has so far been impossible. 1