橈動脈旁植入式脈壓與動脈硬化監測系統之研發

Development of a pulse pressure and atherosclerosis monitoring system based on radial artery implant cuff

周健銘(Meng-Kin Chao)

指導教授 ： 婁世亮

中原大學/工學院/生物醫學工程研究所/碩士(2011年)

https://doi.org/10.6840/cycu201101126

摘要

人隨著年齡增長，心血管亦隨之老化而失去彈性，引發高血壓與動脈硬化的風險亦相形提高，進而誘發更嚴重的心血管疾病如冠狀動脈栓塞等，因此早期的診斷與治療十分重要。本研究之目的為開發無電池植入式心血管監測系統，以提供長期監測心血管狀況的解決方案。植入端系統之電源是由體外以射頻耦合方式提供，藉銬形脈壓感測器量測動脈壓訊號，經由無線傳輸系統將訊號傳至體外錶型中繼系統，繼以藍芽之傳輸方式送至電腦進行脈波增大指數(augmentation index, AIx)運算。已完成之中繼系統在1.9瓦特的消耗功率下，與植入端系統間之傳輸速率可達54封包/秒，並有7公釐之垂直傳輸距離，及24公釐之最大側向位移變化量。脈壓感測器之雛型品為一款具有生物相容性之銬型液囊，其規格為直徑8公釐高14公釐之圓柱體。系統驗證中，將脈壓感測系統植入於紐西蘭兔之股動脈處，可有七天之脈壓訊號量測能力；然而在量測至第四天時出現訊號失真情況，歸因於脈壓感測器鬆脫及破損。總言之，吾人已成功研發出一套植入式脈壓感測系統，並透過動物實驗驗證其初步功能性，具有潛力可應用於心血管疾病之監測。

關鍵字

植入式心血管監測系統 ； 銬型脈壓感測器 ； 動脈硬化 ； 血管擴張指數

並列摘要

The central arteries become ageing and stiff with increase of age. It is important to early diagnose these deleterious effects because they increase cardiovascular risks such as morbidity of hypotension and atherosclerosis resulted in angina pectoris or myocardial infarction. The ultimate goal of this study is to develop a batteryless implantable cardiovascular monitoring system to provide a solution of long term cardiovascular status monitoring. The implanted system (IS) was equipped with a cuff sensor directly detecting arterial pressure signals and was powered by an external relay system (ERS) based on radio frequency (RF) technology. The detected signals were transferred to a personal computer via a blue-tooth device implemented in the ERS. An index representing the stiffness of artery vessels, known as augmentation index (AIx), was then calculated from the detected signals. The wireless communications between the completed ERS and IS can tolerate a vertical displacement of 7 mm, and maximum horizontal displacement of 24 mm, which data transfer rate is 54 packets per second with power consumption of 1.9 W. The prototype of cuff pressure sensor has been produced; it is a biocompatible cylindrical cuff sac with a length of 14 mm and diameter of 8 mm. An in vivo study was performed in this course by sensing femoral arterial pressure of New Zealand white rabbits. The result show that the developed system is able to perform pressure measurements for seven days, but the distortion of the detected signals appeared at the fourth day. The cause is likely due to the loose of the pressure sensor from the femoral arteries. In conclusion, this course completed an implantable pressure sensing system and its functionality has been confirmed with the in vivo studies. There is a potential that the system can be applied for monitoring cardiovascular diseases.

並列關鍵字

Augmentation index ； Cuff pressure sensor ； Implantable cardiac vascular monitoring system ； Atherosclerosis

參考文獻

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