Takazawa K, Tanaka N, Fujita M, Matsuoka O, Saiki T, Aikawa M, Tamura S, Ibukiyama C
The Second Department of Internal Medicine, Tokyo Medical College, Japan.
Hypertension. 1998 Aug;32(2):365-70. doi: 10.1161/01.hyp.32.2.365.
To evaluate the clinical application of the second derivative of the fingertip photoplethysmogram waveform, we performed drug administration studies (study 1) and epidemiological studies (study 2). In study 1, ascending aortic pressure was recorded simultaneously with the fingertip photoplethysmogram and its second derivative in 39 patients with a mean+/-SD age of 54+/-11 years. The augmentation index was defined as the ratio of the height of the late systolic peak to that of the early systolic peak in the pulse. The second derivative consists of an a, b, c, and d wave in systole and an e wave in diastole. Ascending aortic pressure increased after injection of 2.5 microg angiotensin from 126/74 to 160/91 mm Hg and decreased after 0.3 mg sublingual nitroglycerin to 111/73 mm Hg. The d/a, the ratio of the height of the d wave to that of the a wave, decreased after angiotensin from -0.40+/-0.13 to -0.62+/-0.19 and increased after nitroglycerin to -0.25+/-0.12 (P<0.001 and P<0.001, respectively). The negative d/a increased with increases in plethysmographic and ascending aortic augmentation indices (r=0.79, P<0.001, and r=0.80, P<0.001, respectively). The negative d/a reflects the late systolic pressure augmentation in the ascending aorta and may be useful for noninvasive evaluation of the effects of vasoactive agents. In study 2, the second derivative of the plethysmogram waveform was measured in a total of 600 subjects (50 men and 50 women in each decade from the 3rd to the 8th) in our health assessment center. The b/a ratio increased with age, and c/a, d/a, and e/a ratios decreased with age. Thus, the second derivative aging index was defined as b-c-d-e/a. The second derivative wave aging index (y) increased with age (x) (r=0.80, P<0.001, y=0.023x-1.515). The second derivative aging index was higher in 126 subjects with any history of diabetes mellitus, hypertension, hypercholesterolemia, and ischemic heart disease than in age-matched subjects without such a history (-0.06+/-0.36 versus -0.22+/-0.41, P<0.01). Women had a higher aging index than men (P<0.01). The b-c-d-e/a ratio may be useful for evaluation of vascular aging and for screening of arteriosclerotic disease.
为评估指尖光电容积脉搏波波形二阶导数的临床应用，我们进行了药物给药研究（研究1）和流行病学研究（研究2）。在研究1中，对39例平均年龄为54±11岁的患者同时记录升主动脉压力、指尖光电容积脉搏波及其二阶导数。增强指数定义为脉搏中收缩晚期峰值高度与收缩早期峰值高度之比。二阶导数在收缩期由a、b、c和d波组成，在舒张期由e波组成。注射2.5μg血管紧张素后，升主动脉压力从126/74 mmHg升高至160/91 mmHg，舌下含服0.3 mg硝酸甘油后降至111/73 mmHg。血管紧张素注射后，d/a（d波高度与a波高度之比）从-0.40±0.13降至-0.62±0.19，硝酸甘油注射后升至-0.25±0.12（分别为P<0.001和P<0.001）。负d/a随光电容积脉搏波和升主动脉增强指数的增加而增加（分别为r=0.79，P<0.001和r=0.80，P<0.001）。负d/a反映升主动脉收缩晚期压力增强，可能有助于无创评估血管活性药物的作用。在研究2中，我们健康评估中心共对600名受试者（从30岁到80岁，每十年各50名男性和50名女性）测量了光电容积脉搏波波形的二阶导数。b/a比值随年龄增加，c/a、d/a和e/a比值随年龄降低。因此，二阶导数衰老指数定义为b-c-d-e/a。二阶导数波衰老指数（y）随年龄（x）增加（r=0.80，P<0.001，y=0.023x-1.515）。126例有糖尿病、高血压、高胆固醇血症和缺血性心脏病病史的受试者的二阶导数衰老指数高于无此类病史的年龄匹配受试者（-0.06±0.36对-0.22±0.41，P<0.01）。女性的衰老指数高于男性（P<0.01）。b-c-d-e/a比值可能有助于评估血管衰老和筛查动脉硬化疾病。
