Radial arterial waves for chemotherapy- and radiotherapy-related myocardial damage identification in patients with breast cancer.

Introduction: Chemotherapy and radiation therapy for breast cancer cause side effects, such as cardiovascular changes, which can be monitored with echocardiography. However, more convenient methods are always encouraged. Radial arterial waves that are used to detect cardiovascular changes can be used to assist in confirming cardiovascular changes. Aim: This retrospective study aimed to analyze the frequency and time domains of the radial artery pulse wave in patients with breast cancer to understand its effectiveness in identifying cardiovascular changes. Methods: Patients with breast cancer were screened from the pulse examination records in Changhua Christian Hospital and divided into the treatment and remission groups. After unlinking the data, the pulse data were analyzed for the breast cancer treatment and remission group, including the average value of the parameters of four consecutive pulse diagnosis records in four consecutive months to test the difference in pulse waves due to breast cancer treatment between the two groups. Additionally, the pulse wave stability of the two groups was compared using the coefficient of variation. Results and conclusion: The comparison of the pulse wave data between 19 patients in the treatment group and 40 patients in the remission group revealed 45 parameters in time and 50 in frequency domains. D3, ND3, NA1, and NT1 are the four parameters with significant differences (p < 0.05), which are all related to heart function, and mainly related to cardiac output and peripheral resistance, indicating that patients in the treatment period have poor heart function. No difference was found in the degree of data dispersion between the two groups. Cardiovascular side effects caused by breast cancer treatment can mainly be shown in the pulse wave time domain.

Wall Properties of Elastic and Muscular Arteries in Children and Adolescents at Increased Cardiovascular Risk.

BACKGROUND: Pulse wave velocity (PWV) assessment represents a simple method to estimate arterial distensibility. At present, carotid-femoral PWV (cf-PWV) is considered the gold standard method in the non-invasive evaluation of the elastic properties of the aorta. On the other hand, the mechanical properties of muscular arteries can be evaluated on the axillo-brachial-radia axis by estimating the carotid-radial PWV (cr-PWV). While a number of studies have addressed these issues in adults, limited information is available on the respective features of cf-PWV and cr-PWV and on their modulating factors in children and adolescents at increased cardiovascular risk. METHODS: The mechanical properties of the predominantly elastic (aorta) and muscular (axillo-brachial-radial axis) arteries were evaluated in a pediatric population characterized by either elevated blood pressure (BP) or excess body weight, and the main factors affecting cf-PWV and cr-PWV values in these individuals were investigated. RESULTS: 443 children and adolescents (median age 11.5 years, 43.3% females) were enrolled; 25% had BP values >90th percentile and 81% were excess weight. The cf-PWV values were significantly lower than the cr-PWV values: median (Q1-Q3) = 4.8 m/s (4.3-5.5) and 5.8 m/s (5.0-6.5), respectively (p < 0.001). The pubertal development (p < 0.03), systolic BP and diastolic BP z-scores (p = 0.002), heart rate (p < 0.001), and waist-to-height ratio (p < 0.005) were significantly associated with cf-PWV values. No significant association was found between BMI z-score and cf-PWV. Predictors of high cf-PWV (>95th percentile) were the heart rate (OR 1.07, 95%CI 1.04-1.10, p < 0.001) and waist-to-height ratio (OR 1.06, 95%CI 1.0-1.13, p = 0.04). The variables significantly related with cr-PWV values were diastolic BP z-score (p = 0.001), heart rate (p < 0.01), and HOMA index (p < 0.02). No significant association was found between the cr-PWV and BMI z-score or waist-to-height ratio. CONCLUSIONS: Systolic and diastolic BP values and central obesity are associated with aortic stiffness in a population of children and adolescents at increased cardiovascular risk. In contrast, diastolic BP, heart rate, and levels of insulin resistance appear to be related to distensibility of the upper limb vascular district.

Machine learning classification of polycystic ovary syndrome based on radial pulse wave analysis.

BACKGROUND: Patients with Polycystic ovary syndrome (PCOS) experienced endocrine disorders that may present vascular function changes. This study aimed to classify and predict PCOS by radial pulse wave parameters using machine learning (ML) methods and to provide evidence for objectifying pulse diagnosis in traditional Chinese medicine (TCM). METHODS: A case-control study with 459 subjects divided into a PCOS group and a healthy (non-PCOS) group. The pulse wave parameters were measured and analyzed between the two groups. Seven supervised ML classification models were applied, including K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Decision Trees, Random Forest, Logistic Regression, Voting, and Long Short Term Memory networks (LSTM). Parameters that were significantly different were selected as input features and stratified k-fold cross-validations training was applied to the models. RESULTS: There were 316 subjects in the PCOS group and 143 subjects in the healthy group. Compared to the healthy group, the pulse wave parameters h3/h1 and w/t from both left and right sides were increased while h4, t4, t, As, h4/h1 from both sides and right t1 were decreased in the PCOS group (P < 0.01). Among the ML models evaluated, both the Voting and LSTM with ensemble learning capabilities, demonstrated competitive performance. These models achieved the highest results across all evaluation metrics. Specifically, they both attained a testing accuracy of 72.174% and an F1 score of 0.818, their respective AUC values were 0.715 for the Voting and 0.722 for the LSTM. CONCLUSION: Radial pulse wave signal could identify most PCOS patients accurately (with a good F1 score) and is valuable for early detection and monitoring of PCOS with acceptable overall accuracy. This technique can stimulate the development of individualized PCOS risk assessment using mobile detection technology, furthermore, gives physicians an intuitive understanding of the objective pulse diagnosis of TCM. TRIAL REGISTRATION: Not applicable.

[Individualized analysis of pulse wave shape before and after a single accurate power exercise in patients with long-term chronic diseases].

Objective: To observe and study the resting radial artery pulse wave and changes after a single individualized exercise in patients with long-term chronic diseases. Methods: We selected 16 patients with chronic disease (disease duration ≥5 years) who have been clearly diagnosed as hypertension and/or diabetes and/or hyperlipemia, and first completed the symptom-restricted limit cardiopulmonary exercise testing (CPET). Then a single individualized exercise with Δ50% power as the exercise intensity was completed within one week after CPET. We measured and recorded 50s pulse wave data before exercise and 10 min, 20 min, 30 min after exercise, then obtained each pulse wave characteristic point: starting point (B), main wave peak point (P1), trough of a repulse point (PL), crest of a repulse point (P2), and end point (E). The raw data of the abscissa (time T) and ordinate (amplitude Y) corresponding to each point were derived from the instrument. We treated the end point E of the previous pulse wave as the start point B of the next wave, returned TB to zero, and got the main observation indicators: YB, YP1, YPL, YP2 and TP1, TPL, TP2, TE, and calculated out ΔYP1, ΔYPL, ΔYP2, TE-TPL, (TE-TPL)/TPL, pulse rate, S1, S2 ,ΔYP2-ΔYPL and TP2-TPL as secondary observation indicators. Then calculated the occurrence rate of dicrotic wave with obvious crest. Finally we analyzed individually the 50 s pulse wave data of each patient before and after exercise, and then averaged all the data for overall analysis. Results: ①16 patients with long-term chronic diseases (males 14, females 2), ages (53.7±12.6, 28~80) years old, height (171.7±6.6, 155~183) cm, body weight (80.0±13.5, 54~98) kg. 2YB (91.5±10.8, 71.1~108.6), YP1 (203.6±24.7, 162.7~236.3), YPL (127.1±6.2, 118.2~140.3), YP2 (125.9±6.2, 115.7~137.7), TP1 ( 137.2±22.3, 103.0~197.1), TPL (368.7±29.5, 316.3~434.0), TP2 (422.7±32.8, 376.9~494.7), TE (883.4±95.0, 672.2~1003.3), ΔYP1 (112.1±33.8, 60.3~ 157.5), ΔYPL (35.5±14.2, 17.5~66.2), ΔYP2 (34.4±13.3, 20.0~62.9), TE-TPL (514.6±85.4, 341.4~621.9), (TE-TPL)/TPL (1.4±0.2, 1.0~1.7), pulse rate (68.8±8.4, 59.8~89.3), S1 (0.9±0.3, 0.4~1.4), S2 (0.0±0.0, -0.1~0.0), ΔYP2-ΔYPL (-1.2±2.6,- 6.5 ~ 2.5), TP2-TPL (54.0 ± 10.8, 33.6 ~ 81.1). ③10min after exercise, YB, YPL, YP2, TPL, TE decreased, YP1 increased. ΔYPL, TE-TPL, (TE-TPL)/TPL decreased, and ΔYP1, pulse rate, S1, ΔYP2-ΔYPL, TP2 -TPL increased (all P<0.05). The change trend of pulse wave at 20min and 30min after exercise was consistent with that at 10min after exercise, but most indicators gradually recovered to the resting level before exercise from 10 min. ④The appearance rate of dicrotic wave with obvious crest in 16 patients with long-term chronic disease at rest was 28.6%, and the appearance rate of 10 min (65.7%), 20 min (77.1%), 30 min (73.7%) after exercise was significantly increased (all P< 0.01). In 6 patients, the incidence of dicrotic waves with obvious peaks after exercise was significantly increased, and it could continue until 30 minutes. In 3 patients, the incidence increased significantly 10 minutes after exercise, and began to decrease at 20 minutes. In 1 patient, the rate of appearance only started to increase 20 minutes after exercise. In 2 patients, the incidence increased 10 minutes after exercise and then decreased. In 1 patient, the rate of occurrence increased briefly 20 minutes after exercise and then decreased. The incidence of 1 patient dropped after exercise and began to rise at 20 minutes. In 2 cases, the incidence rate did not increase after exercise, and it increased slightly after 30 minutes. Conclusion: In patients with long-term chronic diseases, the radial artery pulse wave is short and the dicrotic wave is not obvious or even disappears. After a single precise power exercise, the main wave increases, the position of the dicrotic wave decreases, and the amplitude increases. The specific response should be analyzed individually.

[Individualization analysis of pulse wave shape characteristics before and after single precise power exercise in young healthy subjects].

Objective: To observe and study the resting radial artery pulse wave and the pulse wave changes after a single individualized exercise in young healthy normal subjects. Methods: We selected 16 young healthy graduate students, advanced training doctors, and visiting scholars from Fuwai Hospital without any disease diagnosis and low daily exercise. They first completed the symptom-restricted limit cardiopulmonary exercise testing (CPET). A single individualized exercise with Δ50% power as the exercise intensity was completed within one week after CPET. We measured and recorded 50 s pulse wave data before exercise and 10 min, 20 min, 30min after exercise, let the instrument automatically fix the point and then manually recheck to obtain each pulse wave characteristic point: starting point (B), main wave peak point (P1), trough of a repulse point (PL), crest of a repulse point (P2), and end point (E), and the raw data of the abscissa (time T) and ordinate (amplitude Y) corresponding to each point were derived from the instrument. We treated the end point E of the previous pulse wave as the start point B of the next wave, returned TB to zero, and got the main observation indicators: YB, YP1, YPL, YP2 and TP1, TPL, TP2, TE, and calculated out ΔYP1 (YP1-YB), ΔYPL (YPL-YB), ΔYP2 (YP2-YB), TE-TPL, (TE-TPL)/TPL, pulse rate, S1 (the slope of main wave ascending branch), S2 (the slope of dicrotic ascending branch), ΔYP2-ΔYPL and TP2-TPL as secondary observation indicators; defined the dicrotic wave with obvious crest as YP2>YPL, and calculated the occurrence rate of dicrotic wave with obvious crest (number of waveforms with YP2>YPL in 50 s /total number of waveforms×100%). We analyzed individually the 50 s pulse wave data of each subject before and after exercise, and then averaged all the data for overall analysis. Results: ①16 healthy young subjects (males 10, females 6), age (30.6±6.4, 24~48) years old; height (170.4±8.2, 160~188) cm; body mass (63.9±12.8, 43~87) kg. ②YB (87.2±5.8, 78.1~95.9), YP1 (223.5±15.8, 192.7~242.3), YPL (122.8±7.8, 110.0~133.8), YP2 (131.4±4.9, 116.7~137.5), TP1 (126.2±42.2, 94.2~280.0), TPL (360.2±44.8, 311.5~507.3), TP2 (432.4±50.8, 376.2~589.0), TE (899.7±86.9, 728.3~1042.0). ΔYP1 (136.3±19.9, 96.8~ 158.6), ΔYPL (35.7±10.7, 16.0~55.7), ΔYP2 (44.3±8.1, 22.5~56.5), TE-TPL (539.5±79.3, 405.9~691.3), (TE-TPL)/TPL (1.5±0.3, 0.8~2.0), pulse rate (67.3±6.6, 57.6~82.4), S1 (1.1±0.2, 0.6~1.4), S2 (0.1±0.1, 0.0~0.2), ΔYP2-ΔYPL (8.6±6.1, 0.9 ~19.8), TP2-TPL (72.3±19.9, 38.3~108.4). ③10 min after exercise, YPL (97.0±13.2 vs 122.8±7.8), YP2 (109.6±12.8 vs 131.4±4.9), ΔYPL (6.6±9.8 vs 35.7±10.7), ΔYP2 (19.3±11.2 vs 44.3±8.1), TE (667.8±123.1 vs 899.7±86.9), TE-TPL (330.2±128.4 vs 539.5±79.3), (TE-TPL)/TPL (1.0±0.4 vs 1.5±0.3) decreased, while the pulse rate (92.2± 14.0 vs 67.3±6.6), ΔYP2-ΔYPL (12.7±9.7 vs 8.6±6.1), TP2-TPL (98.0±38.1 vs 72.3±19.9) increased (all P<0.05). The trend of pulse wave changes at 20 min and 30 min after exercise was consistent with that at 10 min after exercise, but from 20 min, most of the indicators gradually recovered to the resting level before exercise. ④The incidence of dicrotic waves with obvious peaks in 16 young healthy persons at rest was 94.5%, and increased at 10 min (96.3%), 20 min (98.5%), and 30 min (99.8%) after exercise (all P<0.01). Among them, the incidence of dicrotic waves with obvious peaks before and after exercise was maintained at about 100% in 10 subjects. The appearance rate of 2 cases had reached 100% before exercise, but it decreased at 10 minutes after exercise, and then continued to increase, at 30 minutes recovered to 100%. Three subjects had a low resting rate and started to increase after exercise. In 1 case, the rate was low only 20 minutes after exercise, considering the influence of human factors. Conclusion: The influence of exercise on the pulse wave of normal people is mainly reflected in the dicrotic wave. On the whole, after a single precise power exercise, the position of the dicrotic wave is reduced, the amplitude is deepened, and the appearance rate of the dicrotic wave with obvious crest is generally increased, and this change can be maintained for at least 30 minutes. From an individual point of view, the response trend of each subject is different.

Blood Pressure and Body Weight Have Different Effects on Pulse Wave Velocity and Cardiac Mass in Children.

BACKGROUND: High blood pressure (BP) and excess weight can lead to early cardiovascular organ damage already in children. Carotid-femoral pulse wave velocity (cf-PWV) is the non-invasive gold standard method for assessing aortic stiffness, while carotid-radial PWV (cr-PWV) provides information on the distensibility of the upper limb arteries. The aim of this study was to evaluate the relationship of BP and BMI z-scores with arterial stiffness and left ventricular mass index (LVMI) in a pediatric population. METHODS: In 343 children (57.7% males; age ± SD 11.7 ± 2.9 years), systolic (SBP) and diastolic (DBP) BP, BMI, cf-PWV, cr-PWV and LVMI were measured. A multiple linear regression model was used to assess the impact of BMI and SBP (or DBP) z-scores on cf-PWV, cr-PWV and LVMI. RESULTS: About 21% of children were normal weight, 34% were overweight and 45% obese. Adjusted for possible confounders, SBP and DBP z-scores were significantly associated with cf-PWV (p < 0.001), while only DBP z-scores were related to cr-PWV (p < 0.01). BMI was neither associated with cf-PWV nor with cr-PWV values but was a strong predictor of LVMI (<0.001), whereas cardiac mass and BP z-scores were not related. CONCLUSIONS: Our study suggests that, in children, elevated BP values and excess weight may have different effects on the heart and the vessels in causing early cardiovascular alterations.

Risk assessment of macrovascular and microvascular events in patients with type 2 diabetes by analyzing the amplitude variation of the fourth harmonic component of radial pulse wave.

This investigation explored the hypothesis that whether the coefficient of variation of the fourth harmonic amplitude of the radial pulse wave (C4CV) predicts the risk of macrovascular and microvascular events in patients with type 2 diabetes mellitus (T2DM). Radial pulse wave and brachial blood pressure were measured at baseline in 2324 patients with T2DM and C4CV was calculated using the Fourier series method. Macrovascular and microvascular events during follow-up were determined by medical records. We plotted the Kaplan-Meier curve and performed a Cox proportional hazard model and a log-rank test to estimate the effectiveness of C4CV as a risk predictor. We divided patients into quartile groups based on C4CV (<4.3%, 4.3% to 6.8%, 6.8% to 11.4%, and >11.4%). Compared with patients with C4CV < 4.3%, patients with C4CV> 11.4% had a double incidence of macrovascular events (hazard ratio, 2.13; 95% CI, 1.70-2.67) and microvascular events (hazard ratio, 2.08; 95% CI, 1.67-2.58), and the incidence of cardiovascular death was three times (hazard ratio, 3.03; 95% CI, 1.10-8.83). The Cox regression analysis demonstrated that the risk of both macrovascular and microvascular outcomes increases with the increase in quartile level of C4CV value (P < 0.0001). These associations remained after adjustment for age, gender, smoking, systolic blood pressure, diastolic blood pressure, dyslipidemia, diabetes duration, Hba1c, and cardiovascular disease (P < 0.0001). C4CV is a novel independent predictor of cardiovascular mortality, macrovascular events, and microvascular events in patients with T2DM.

Triglycerides are a predictive factor for arterial stiffness: a community-based 4.8-year prospective study.

BACKGROUND: Epidemiological studies have disclosed an independent effect of triglycerides on coronary heart disease despite achievement of low-density lipoprotein cholesterol goals with statin therapy. Arterial stiffness has been increasingly recognized as a strong predictor of cardiovascular disease and atherosclerotic disease. The association between triglycerides and arterial stiffness is not well characterized. We aimed to determine the relationship between triglycerides and arterial stiffness in a community-based longitudinal sample from Beijing, China. METHODS: We related levels of plasma TGs to measures of arterial stiffness (carotid-femoral pulse wave velocity [PWV] and carotid-radial PWV) in 1447 subjects (mean age, 61.3 years) from a community-based population in Beijing, China. RESULTS: After a median follow-up interval of 4.8 years, multiple linear regression analysis revealed that TGs were independently associated with carotid-femoral PWV (ß = 0.747, P < 0.001) and carotid-radial PWV (ß = 0.367, P = 0.001). In the group older than 65 years, the association between baseline TG levels and follow-up carotid-femoral PWV (ß = 1.094, P = 0.001) and carotid-radial PWV (ß = 0.524, P = 0.002) were strengthened. In forward stepwise multivariate logistic regression analysis, every SD increase in TGδ was associated with a 1.296-increased likelihood of the presence of carotid-femoral PWVδII (OR [per SD increase in TGδ]: 1.296; 95% CI: 1.064 ~ 1.580; P = 0.010) in Model 2, whereas the relationship between TGδ and carotid-radial PWVδII disappeared. In addition, the relationship was strengthened between TGδ and the presence of carotid-femoral PWVδII (OR 1.526, 95% CI: 1.088-2.141, P = 0.014) in the group older than 65 years but not carotid-radial PWVδII. No association was noted in subjects younger than 65 years. CONCLUSIONS: Lower triglyceride levels were significantly associated with decreases in carotid-femoral PWV, indicating that achieving low TG levels may be an additional therapeutic consideration in subjects with atherosclerotic disease.

Feasibility of a clinical trial to assess the effect of dietary calcium v. supplemental calcium on vascular and bone markers in healthy postmenopausal women.

Whether supplemental Ca has similar effects to dietary Ca on vascular and bone markers is unknown. The present trial investigated the feasibility of applying dietary and supplemental interventions in a randomised-controlled trial (RCT) aiming to estimate the effect of supplemental Ca as compared with dietary Ca on vascular and bone markers in postmenopausal women. In total, thirteen participants were randomised to a Ca supplement group (CaSuppl) (750 mg Ca from CaCO3+450 mg Ca from food+20 µg vitamin D supplement) or a Ca diet group (CaDiet) (1200 mg Ca from food+10 µg vitamin D supplement). Participants were instructed on Ca consumption targets at baseline. Monthly telephone follow-ups were conducted to assess adherence to interventions (±20 % of target total Ca) using the multiple-pass 24-h recall method and reported pill count. Measurements of arterial stiffness, peripheral blood pressure and body composition were performed at baseline and after 6 and 12 months in all participants who completed the trial (n 9). Blood and serum biomarkers were measured at baseline and at 12 months. Both groups were compliant to trial interventions (±20 % of target total Ca intake; pill count ≥80 %). CaSuppl participants maintained a significantly lower average dietary Ca intake compared with CaDiet participants throughout the trial (453 (sd 187) mg/d v. 1241 (sd 319) mg/d; P<0·001). There were no significant differences in selected vascular outcomes between intervention groups over time. Our pilot trial demonstrated the feasibility of conducting a large-scale RCT to estimate the differential effects of supplemental and dietary Ca on vascular and bone health markers in healthy postmenopausal women.

Reliability assessment for pulse wave measurement using artificial pulse generator.

This study aimed to assess intrinsic reliabilities of devices for pulse wave measurement (PWM). An artificial pulse generator system was constructed to create a periodic pulse wave. The stability of the periodic output was tested by the DP103 pressure transducer. The pulse generator system was then used to evaluate the TD01C system. Test-re-test and inter-device reliability assessments were conducted on the TD01C system. First, 11 harmonic components of the pulse wave were calculated using Fourier series analysis. For each harmonic component, coefficient of variation (CV), intra-class correlation coefficient (ICC) and Bland-Altman plot were used to determine the degree of reliability of the TD01C system. In addition, device exclusion criteria were pre-specified to improve consistency of devices. The artificial pulse generator system was stable to evaluate intrinsic reliabilities of devices for PWM (ICCs > 0.95, p < 0.001). TD01C was reliable for repeated measurements (ICCs of test-re-test reliability > 0.95, p < 0.001; CVs all < 3%). Device exclusion criteria successfully excluded the device with defect; therefore, the criteria reduced inter-device CVs of harmonics and improved consistency of the selected devices for all harmonic components. This study confirmed the feasibility of intrinsic reliability assessment of devices for PWM using an artificial pulse generator system. Moreover, potential novel findings on the assessment combined with device exclusion criteria could be a useful method to select the measuring devices and to evaluate the qualities of them in PWM.

Development of a Standard Protocol for the Harmonic Analysis of Radial Pulse Wave and Assessing Its Reliability in Healthy Humans.

This study was aimed to establish a standard protocol and to quantitatively assess the reliability of harmonic analysis of the radial pulse wave measured by a harmonic wave analyzer (TD01C system). Both intraobserver and interobserver assessments were conducted to investigate whether the values of harmonics are stable in successive measurements. An intraclass correlation coefficient (ICC) and a Bland-Altman plot were used for this purpose. For the reliability assessments of the intraobserver and the interobserver, 22 subjects (mean age 45 ± 14 years; 14 males and 8 females) were enrolled. The first eleven harmonics of the radial pulse wave presented excellent repeatability ([Formula: see text] and [Formula: see text]) for the intraobserver assessment and high reproducibility (ICCs range from 0.83 to 0.96 and [Formula: see text]) for the interobserver assessment. The Bland-Altman plot indicated that more than 90% of harmonic values fell within two standard deviations of the mean difference. Thus, we concluded that the harmonic analysis of the radial pulse wave using the TD01C system is a feasible and reliable method to assess a hemodynamic characteristic in clinical trial.

The differences in waveform between photoplethysmography pulse wave and radial pulse wave in movement station.

OBJECTIVE: There are many similarities between the photoplethysmography(PPG) pulse wave and the radial pulse when a body is in a stationary state, but the difference between them under conditions of movement is not yet clear. Finding these differences may help further understanding of the cardiovascular system. METHODS: PPG and radial pulse wave were recorded simultaneously while subjects were conducting a bicycle exercise test that included the resting and exercise state, while the K and K' parameters were being acquired from the PPG and radial pulse, respectively. Furthermore, the pulse objective pattern is observed via the time domain waveform and XY graph. RESULTS: When the body's state of movement changes dramatically, there is a time difference between the pulse parameter K and the pulse amplitude, and the difference of the pulse pattern is enhanced during the exercising phase. CONCLUSION: Radial pulse waves are not the same as PPG during exercise in either the pulse parameter or the pulse pattern. This information can be used to further evaluate the state of arterial circulation and microcirculation.

Morphology variability of radial pulse wave during exercise.

Pulse wave contains much information on a cardiovascular system. Pulse wave variability during exercise is of great significance as it reflects more information combining with pulse wave under stationary state. This paper studied the morphology variability of radial pulse wave during exercise. Radial pulse waves were collected from 30 subjects with two pressure pulse sensors worn at the wrists of the right and left hands, respectively. Electrocardiography (ECG) was also detected synchronously. After data preprocessing and feature point extraction, the variability of several parameters of pulse wave and ECG were analyzed. It is notable that pulse rate (PR) and heart rate (HR) change synchronously. During the exercise period, both systolic phase and diastolic phase of a radial pulse shorten but the latter is more obvious. The amplitude of the dicrotic notch decreases and even turns negative. Aligning the radial pulse waveforms together, the radial pulse waveforms prior to, during and after exercise coincide with each other except for some details like the tidal wave which fades away during exercise.

Comparison of noninvasive assessments of central blood pressure using general transfer function and late systolic shoulder of the radial pressure wave.

BACKGROUND: Central systolic blood pressure (cSBP) can be derived by the general transfer function of the radial pressure wave, as used in the SphygmoCor device, or by regression equation from directly measured late systolic shoulder of the radial pressure wave (pSBP2), as used in the Omron HEM-9000AI device. The aim of this study was to compare the SphygmoCor estimates of cSBP with 2 estimates of cSBP provided by the Omron HEM-9000AI (cSBP, pSBP2) in a large cohort of the white population. METHODS: In 391 patients aged 52.3±13.5 years (46% men) from the Czech post-MONICA Study, cSBP was measured using the SphygmoCor and Omron HEM-9000AI devices in random order. RESULTS: Omron cSBP and pSBP2 were perfectly correlated (r = 1.0; P < 0.0001). There was a strong correlation (r = 0.97; P < 0.0001) between Omron and SphygmoCor cSBP estimates, but Omron estimate was 13.1±4.7mm Hg higher than SphygmoCor cSBP. On the other hand, Omron pSBP2 strongly correlated with SphygmoCor cSBP (r = 0.97; P < 0.0001) and was 1.7±4.2mm Hg lower than SphygmoCor cSBP. In multivariable analysis, anthropometric and cardiovascular risk factors explained only 10% of the variance of the cSBP difference between devices while explaining 52% of the systolic blood pressure amplification variance. CONCLUSIONS: Estimation of cSBP based on the late systolic shoulder of the radial wave provides a comparable accuracy with the validated general transfer function. When comparing Omron HEM-9000AI and SphygmoCor estimates of cSBP, Omron pSBP2 should be used. The difference between both devices in cSBP may be explained by differences in calibration.

Estimación de la velocidad de propagación aórtica basada en el análisis de la onda de pulso radial / Velocity estimation of aortic propagation based on radial pulse wave analysis

Se exploró la posibilidad de utilizar la morfología del registro de onda de pulso radial obtenida mediante un transductor de movimiento para evaluar la velocidad de propagación aórtica. Se efectuó el registro de onda de pulso en arteria radial mediante un transductor apoyado sobre la zona de palpación del pulso, sobre un conjunto de 167 voluntarios varones sanos normotensos de edades comprendidas entre la 2ª y la 7ª década. Se identificó en los registros la onda reflejada y se definió un coeficiente de velocidad como el cociente entre la talla del individuo y el tiempo transcurrido entre el máximo de la onda sistólica y el instante de llegada de dicha onda. Se halló que en los normotensos el coeficiente mencionado aumentó en forma lineal con la edad, en una proporción similar al aumento de velocidad de propagación aórtica medido con otros métodos. Se repitió el procedimiento en otro conjunto de 125 varones hipertensos sin otros factores de riesgo, de edades entre la 3ª y la 7ª década, hallándose valores similares a los normotensos solamente en la 3ª década, a partir de la cual se registró un incremento significativo de dicho índice. Tales hallazgos sustentan la factibilidad de utilizar tal tipo de registros para evaluar indirectamente la velocidad de propagación junto con el índice de aumentación, un parámetro habitualmente utilizado en el análisis de onda de pulso.

We analyzed the possibility of using the radial pulse wave morphology, obtained by a movement transducer, to evaluate the aortic pulse wave velocity. The radial pulse wave signals were obtained by using a transducer, located on the pulse palpation area, in 167 healthy normotensive male volunteers, ages 20 to 70. The reflected wave was identified in every case. Also, a speed coefficient was defined as the ratio between the individual's height and the time between the maximum systolic wave and the arrival time of the reflected wave. We found that the specified coefficient in normotensive individuals increased linearly with age, in a similar way to the increase in aortic propagation velocity measured by other methods. The procedure was repeated on another set of 125 individuals with hypertension, without other risk factors, aged between the 3rd and 7th decade. This time we found similar values to normotensive individuals only on the 3th decade, and a pronounced increase on the velocity coefficient at advanced ages was observed. These findings support the feasibility of using this type of signals to indirectly evaluate the propagation velocity together with the increase index, a parameter commonly used in pulse wave analysis.