title: Determining arterial wave transit time from a single aortic pressure pulse in rats: vascular impulse response analysis.
abstract: Arterial wave transit time (τw) in the lower body circulation is an effective biomarker of cardiovascular risk that substantially affects systolic workload imposed on the heart. This study evaluated a method for determining τwfrom the vascular impulse response on the basis of the measured aortic pressure and an assumed triangular flow (Qtri). The base of the unknown Qtriwas constructed with a duration set equal to ejection time. The timing of the peak triangle was derived using a fourth-order derivative of the pressure waveform. Values of τws obtained using Qtriwere compared with those obtained from the measure aortic flow wave (Qm). Healthy rats (n = 27), rats with chronic kidney disease (CKD; n = 22), and rats with type 1 (n = 22) or type 2 (n = 11) diabetes were analyzed. The cardiovascular conditions in the CKD rats and both diabetic groups were characterized by a decrease in τws. The following significant relation was observed (P < 0.0001): τwtriQ= -1.5709 + 1.0604 × τwmQ(r2= 0.9641). Our finding indicates that aortic impulse response can be an effective method for the estimation of arterial τwby using a single pressure recording together with the assumed Qtri.
authors.affiliation: Department of Physiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.
authors.forename: Ru-Wen
authors.initials: RW
authors.lastname: Chang
authors.affiliation: Department of Emergency Medicine, National Taiwan University Hospital, Chu-Tung Branch, Hsin-Chu, 310, Taiwan.
authors.forename: Chun-Yi
authors.initials: CY
authors.lastname: Chang
authors.affiliation: Department of Physiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.
authors.forename: Liang-Chuan
authors.initials: LC
authors.lastname: Lai
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, 100, Taiwan.
authors.forename: Ming-Shiou
authors.initials: MS
authors.lastname: Wu
authors.affiliation: Institute of Biomedical Engineering, College of Medicine and Engineering, National Taiwan University, Taipei, 100, Taiwan.
authors.forename: Tai-Horng
authors.initials: TH
authors.lastname: Young
authors.affiliation: Department of Surgery, National Taiwan University Hospital, Taipei, 100, Taiwan.
authors.forename: Yih-Sharng
authors.initials: YS
authors.lastname: Chen
authors.affiliation: Department of Surgery, National Taiwan University Hospital, Taipei, 100, Taiwan.|Department of Surgery, National Taiwan University Hospital, Hsin-Chu Branch, Hsin-Chu, 300, Taiwan.
authors.forename: Chih-Hsien
authors.initials: CH
authors.lastname: Wang
authors.affiliation: Department of Physiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.
authors.forename: Kuo-Chu
authors.initials: KC
authors.lastname: Chang
mesh_terms: D000818:Animals; D002318:Cardiovascular Diseases / Q000175:diagnosis*; D002320:Cardiovascular Physiological Phenomena; D008297:Male; D063177:Pulse Wave Analysis; D017208:Rats, Wistar