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Hao Min Cheng - One of the best experts on this subject based on the ideXlab platform.
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Estimation of Cardiovascular Risk Predictors from Non-Invasively Measured Diametric Pulse Volume Waveforms via Multiple Measurement Information Fusion
Scientific Reports, 2018Co-Authors: Zahra Ghasemi, Hao Min Cheng, Shihhsien Sung, Jong Chan Lee, Chang-sei Kim, Chen-huan Chen, Ramakrishna Mukkamala, Jin-oh HahnAbstract:This paper presents a novel multiple measurement information fusion approach to the estimation of cardiovascular risk predictors from non-invasive Pulse Volume waveforms measured at the body’s diametric (arm and ankle) locations. Leveraging the fact that diametric Pulse Volume waveforms originate from the common central Pulse waveform, the approach estimates cardiovascular risk predictors in three steps by: (1) deriving lumped-parameter models of the central-diametric arterial lines from diametric Pulse Volume waveforms, (2) estimating central blood pressure waveform by analyzing the diametric Pulse Volume waveforms using the derived arterial line models, and (3) estimating cardiovascular risk predictors (including central systolic and Pulse pressures, Pulse pressure amplification, and Pulse transit time) from the arterial line models and central blood pressure waveform in conjunction with the diametric Pulse Volume waveforms. Experimental results obtained from 164 human subjects with a wide blood pressure range (systolic 144 mmHg and diastolic 103 mmHg) showed that the approach could estimate cardiovascular risk predictors accurately (r ≥ 0.78). Further analysis showed that the approach outperformed a generalized transfer function regardless of the degree of Pulse pressure amplification. The approach may be integrated with already available medical devices to enable convenient out-of-clinic cardiovascular risk prediction.
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investigation of viscoelasticity in the relationship between carotid artery blood pressure and distal Pulse Volume waveforms
IEEE Journal of Biomedical and Health Informatics, 2018Co-Authors: Jong Chan Lee, Hao Min Cheng, Shihhsien Sung, Zahra Ghasemi, Chang-sei Kim, Chen-huan Chen, Ramakrishna Mukkamala, Jin-oh HahnAbstract:We investigated the relationship between carotid artery blood pressure (BP) and distal Pulse Volume waveforms (PVRs) via subject-specific mathematical modeling. We conceived three physical models to define the relationship: a tube-load model augmented with a gain (TLG), Voigt (TLV), and standard linear solid (TLS) models. We compared these models using PVRs measured via BP cuffs at an upper arm and an ankle as well as carotid artery tonometry waveform collected from 133 subjects. At both upper arm and ankle, PVR was related to carotid artery tonometry by TLV and TLS models better than by TLG model; when root-mean-squared over all the subjects, the systolic and diastolic BP errors between measured carotid artery tonometry waveform and the one estimated from distal PVR reduced from 4.3 mmHg and 4.6 mmHg (TLG) to 1.1 mmHg and 1.0 mmHg (TLS) for the upper arm ( p < 0.0167), and from 2.1 mmHg and 1.7 mmHg (TLG) to 2.1 mmHg and 1.5 mmHg (TLV) for the ankle. Further, TLV and TLS models exhibited superior Akaike's Information Criterion (AIC) in both locations than TLG model. However, the difference between TLG versus TLV and TLS models associated with the ankle was not large. Therefore, the relationship of central arterial BP to arm PVR arises from both wave reflection and viscoelasticity while the relationship to ankle PVR mainly arises from wave reflection. These findings may imply that an effective subject-specific transfer function for estimating accurate central arterial BP from an arm PVR should account for the impact of viscoelasticity.
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central blood pressure monitoring via a standard automatic arm cuff
Scientific Reports, 2017Co-Authors: Keerthana Natarajan, Hao Min Cheng, Shihhsien Sung, Chen-huan Chen, Jin-oh Hahn, Jiankun Liu, Mingwu Gao, Ramakrishna MukkamalaAbstract:Current oscillometric devices for monitoring central blood pressure (BP) maintain the cuff pressure at a constant level to acquire a Pulse Volume plethysmography (PVP) waveform and calibrate it to brachial BP levels estimated with population average methods. A physiologic method was developed to further advance central BP measurement. A patient-specific method was applied to estimate brachial BP levels from a cuff pressure waveform obtained during conventional deflation via a nonlinear arterial compliance model. A physiologically-inspired method was then employed to extract the PVP waveform from the same waveform via ensemble averaging and calibrate it to the brachial BP levels. A method based on a wave reflection model was thereafter employed to define a variable transfer function, which was applied to the calibrated waveform to derive central BP. This method was evaluated against invasive central BP measurements from patients. The method yielded central systolic, diastolic, and Pulse pressure bias and precision errors of −0.6 to 2.6 and 6.8 to 9.0 mmHg. The conventional oscillometric method produced similar bias errors but precision errors of 8.2 to 12.5 mmHg (p ≤ 0.01). The new method can derive central BP more reliably than some current non-invasive devices and in the same way as traditional cuff BP.
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measurement of central aortic Pulse pressure noninvasive brachial cuff based estimation by a transfer function vs a novel Pulse wave analysis method
American Journal of Hypertension, 2012Co-Authors: Hao Min Cheng, Yuanta Shih, Shihhsien Sung, Shaoyuan Chuang, Wenchung Yu, Chen-huan ChenAbstract:BACKGROUND: The prognostic value of central aortic Pulse pressure (PP-C) may have been underestimated due to its measurement inaccuracy. We aimed to investigate the accuracy of noninvasive brachial cuff-based estimation of PP-C by a generalized transfer function (GTF) or a novel Pulse wave analysis (PWA) approach to directly estimate PP-C. METHODS: Invasive high-fidelity right brachial and central aortic pressure tracings, and left brachial Pulse Volume plethysmography (PVP) waveforms from an oscillometric blood pressure (BP) monitor were all digitized simultaneously in 40 patients during cardiac catheterization. An aortic-to-brachial GTF and a PWA multivariate prediction model using the PVP waveforms calibrated to brachial cuff systolic BP (SBP) and diastolic BP(DBP) were constructed. Accuracy of the two methods was examined in another 100 patients against invasively measured PP-C. RESULTS: The error of cuff PP in estimating PP-C was 1.8 ± 12.4 mm Hg. Application of the GTF on noninvasively calibrated PVP waveforms produced reconstructed aortic pressure waves and PP-C estimates with errors of -3.4 ± 11.6 mm Hg (PP-C = reconstructed aortic SBP - aortic DBP) and -2.3 ± 11.4 mm Hg (PP-C = reconstructed aortic SBP - cuff DBP), respectively. The observed systematic errors were proportional to the magnitudes of PP-C. In contrast, the error of the PWA prediction model was 3.0 ± 7.1 mm Hg without obvious proportional systematic error. CONCLUSIONS: Large random and systematic errors are introduced into the PP-C estimates when PP-C is calculated as the difference between the estimated central SBP and central or cuff DBP. The accuracy can be improved substantially with the novel PWA approach.
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measurement of central systolic blood pressure by Pulse Volume plethysmography with a noninvasive blood pressure monitor
American Journal of Hypertension, 2012Co-Authors: Hao Min Cheng, Kangling Wang, Yinghwa Chen, Yuanta Shih, Shihhsien Sung, Shaoyuan ChuangAbstract:Background Central systolic blood pressure (SBP) can be estimated by an oscillometric method developed from a Pulse Volume plethysmography (PVP) device. The present study applied this novel method to a noninvasive blood pressure monitor (NBPM). Methods We enrolled 50 patients (37 men, age range 30–84 years) referred for cardiac catheterization. Invasive right brachial and central aortic pressures (using a dual-sensor pressure catheter), and noninvasive left brachial SBP and diastolic blood pressure (DBP), and PVP waveform (using a customized NBPM) were simultaneously recorded. Central SBP was estimated by analysis of the PVP waveform calibrated to the noninvasive SBP and DBP, using both the original (CSBP-O) and the newly generated (CSBP-N) regression equations. The reproducibility of the invasive central SBP by CSBP-O and CSBP-N was examined using the concordance correlation coefficient. results Overall, the invasive central aortic SBP ranged 86–176 with a mean of 124 ± 21 mm Hg. The mean differences between the estimated and the invasive central SBP were −1.3 ± 6.7 mm Hg for CSBP-O and 0.0 ± 6.2 mm Hg for CSBP-N, respectively. The concordance correlation coefficients for CSBP-O and CSBP-N were 0.94 (95% confidence interval (CI): 0.93–0.94) and 0.95 (95% CI: 0.95–0.96), and both were significantly better than that for the noninvasive brachial SBP (0.87, 0.84–0.91) indicated by non-overlapping CIs. conclusions The PVP method for noninvasive estimation of central SBP can be applied to a commonly used NBPM. Whether the NBPM-derived central SBP is superior to the noninvasive brachial SBP in the prediction of cardiovascular risks remains to be investigated.
Yinghwa Chen - One of the best experts on this subject based on the ideXlab platform.
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measurement of central systolic blood pressure by Pulse Volume plethysmography with a noninvasive blood pressure monitor
American Journal of Hypertension, 2012Co-Authors: Hao Min Cheng, Kangling Wang, Yinghwa Chen, Yuanta Shih, Shihhsien Sung, Shaoyuan ChuangAbstract:Background Central systolic blood pressure (SBP) can be estimated by an oscillometric method developed from a Pulse Volume plethysmography (PVP) device. The present study applied this novel method to a noninvasive blood pressure monitor (NBPM). Methods We enrolled 50 patients (37 men, age range 30–84 years) referred for cardiac catheterization. Invasive right brachial and central aortic pressures (using a dual-sensor pressure catheter), and noninvasive left brachial SBP and diastolic blood pressure (DBP), and PVP waveform (using a customized NBPM) were simultaneously recorded. Central SBP was estimated by analysis of the PVP waveform calibrated to the noninvasive SBP and DBP, using both the original (CSBP-O) and the newly generated (CSBP-N) regression equations. The reproducibility of the invasive central SBP by CSBP-O and CSBP-N was examined using the concordance correlation coefficient. results Overall, the invasive central aortic SBP ranged 86–176 with a mean of 124 ± 21 mm Hg. The mean differences between the estimated and the invasive central SBP were −1.3 ± 6.7 mm Hg for CSBP-O and 0.0 ± 6.2 mm Hg for CSBP-N, respectively. The concordance correlation coefficients for CSBP-O and CSBP-N were 0.94 (95% confidence interval (CI): 0.93–0.94) and 0.95 (95% CI: 0.95–0.96), and both were significantly better than that for the noninvasive brachial SBP (0.87, 0.84–0.91) indicated by non-overlapping CIs. conclusions The PVP method for noninvasive estimation of central SBP can be applied to a commonly used NBPM. Whether the NBPM-derived central SBP is superior to the noninvasive brachial SBP in the prediction of cardiovascular risks remains to be investigated.
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estimation of central systolic blood pressure using an oscillometric blood pressure monitor
Hypertension Research, 2010Co-Authors: Hao Min Cheng, Kangling Wang, Yinghwa Chen, Shingjong Lin, Lungching ChenAbstract:Current noninvasive techniques for assessing central aortic pressure require the recording of an arterial pressure wave using a high-fidelity applanation tonometer. We therefore developed and validated a novel method to estimate the central aortic systolic pressure using an oscillometric blood pressure monitor alone. Invasive high-fidelity right brachial and central aortic pressure waves, and left-brachial Pulse Volume plethysmography from an oscillometric blood pressure monitor, were obtained at baseline and 3 min after administration of sublingual nitroglycerin in 100 patients during cardiac catheterization. In the initial 50 patients (Generation Group), Central systolic blood pressure was predicted by a multi-variate prediction model generated from the comprehensive analysis of the invasive brachial pressure wave, including brachial late-systolic shoulder pressure value and parameters related to wave reflection and arterial compliance. Another prediction model was similarly constructed from the noninvasively calibrated Pulse Volume plethysmography. Both models were validated in the subsequent 50 patients (Validation Group) with results: r=0.98 (P<0.001) and mean difference=0.5+/-4.5 (95% confidence interval -8.3 to 9.3) mm Hg for the invasive model, and r=0.93 (P<0.001) and mean difference=-0.1+/-7.6 (95% confidence interval -15.0 to 14.8) mm Hg for the noninvasive model. Thus, our results indicate that central aortic systolic blood pressure could be estimated by analysis of the noninvasive brachial pressure wave alone from an oscillometric blood pressure monitor.
Shihhsien Sung - One of the best experts on this subject based on the ideXlab platform.
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Estimation of Cardiovascular Risk Predictors from Non-Invasively Measured Diametric Pulse Volume Waveforms via Multiple Measurement Information Fusion
Scientific Reports, 2018Co-Authors: Zahra Ghasemi, Hao Min Cheng, Shihhsien Sung, Jong Chan Lee, Chang-sei Kim, Chen-huan Chen, Ramakrishna Mukkamala, Jin-oh HahnAbstract:This paper presents a novel multiple measurement information fusion approach to the estimation of cardiovascular risk predictors from non-invasive Pulse Volume waveforms measured at the body’s diametric (arm and ankle) locations. Leveraging the fact that diametric Pulse Volume waveforms originate from the common central Pulse waveform, the approach estimates cardiovascular risk predictors in three steps by: (1) deriving lumped-parameter models of the central-diametric arterial lines from diametric Pulse Volume waveforms, (2) estimating central blood pressure waveform by analyzing the diametric Pulse Volume waveforms using the derived arterial line models, and (3) estimating cardiovascular risk predictors (including central systolic and Pulse pressures, Pulse pressure amplification, and Pulse transit time) from the arterial line models and central blood pressure waveform in conjunction with the diametric Pulse Volume waveforms. Experimental results obtained from 164 human subjects with a wide blood pressure range (systolic 144 mmHg and diastolic 103 mmHg) showed that the approach could estimate cardiovascular risk predictors accurately (r ≥ 0.78). Further analysis showed that the approach outperformed a generalized transfer function regardless of the degree of Pulse pressure amplification. The approach may be integrated with already available medical devices to enable convenient out-of-clinic cardiovascular risk prediction.
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investigation of viscoelasticity in the relationship between carotid artery blood pressure and distal Pulse Volume waveforms
IEEE Journal of Biomedical and Health Informatics, 2018Co-Authors: Jong Chan Lee, Hao Min Cheng, Shihhsien Sung, Zahra Ghasemi, Chang-sei Kim, Chen-huan Chen, Ramakrishna Mukkamala, Jin-oh HahnAbstract:We investigated the relationship between carotid artery blood pressure (BP) and distal Pulse Volume waveforms (PVRs) via subject-specific mathematical modeling. We conceived three physical models to define the relationship: a tube-load model augmented with a gain (TLG), Voigt (TLV), and standard linear solid (TLS) models. We compared these models using PVRs measured via BP cuffs at an upper arm and an ankle as well as carotid artery tonometry waveform collected from 133 subjects. At both upper arm and ankle, PVR was related to carotid artery tonometry by TLV and TLS models better than by TLG model; when root-mean-squared over all the subjects, the systolic and diastolic BP errors between measured carotid artery tonometry waveform and the one estimated from distal PVR reduced from 4.3 mmHg and 4.6 mmHg (TLG) to 1.1 mmHg and 1.0 mmHg (TLS) for the upper arm ( p < 0.0167), and from 2.1 mmHg and 1.7 mmHg (TLG) to 2.1 mmHg and 1.5 mmHg (TLV) for the ankle. Further, TLV and TLS models exhibited superior Akaike's Information Criterion (AIC) in both locations than TLG model. However, the difference between TLG versus TLV and TLS models associated with the ankle was not large. Therefore, the relationship of central arterial BP to arm PVR arises from both wave reflection and viscoelasticity while the relationship to ankle PVR mainly arises from wave reflection. These findings may imply that an effective subject-specific transfer function for estimating accurate central arterial BP from an arm PVR should account for the impact of viscoelasticity.
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central blood pressure monitoring via a standard automatic arm cuff
Scientific Reports, 2017Co-Authors: Keerthana Natarajan, Hao Min Cheng, Shihhsien Sung, Chen-huan Chen, Jin-oh Hahn, Jiankun Liu, Mingwu Gao, Ramakrishna MukkamalaAbstract:Current oscillometric devices for monitoring central blood pressure (BP) maintain the cuff pressure at a constant level to acquire a Pulse Volume plethysmography (PVP) waveform and calibrate it to brachial BP levels estimated with population average methods. A physiologic method was developed to further advance central BP measurement. A patient-specific method was applied to estimate brachial BP levels from a cuff pressure waveform obtained during conventional deflation via a nonlinear arterial compliance model. A physiologically-inspired method was then employed to extract the PVP waveform from the same waveform via ensemble averaging and calibrate it to the brachial BP levels. A method based on a wave reflection model was thereafter employed to define a variable transfer function, which was applied to the calibrated waveform to derive central BP. This method was evaluated against invasive central BP measurements from patients. The method yielded central systolic, diastolic, and Pulse pressure bias and precision errors of −0.6 to 2.6 and 6.8 to 9.0 mmHg. The conventional oscillometric method produced similar bias errors but precision errors of 8.2 to 12.5 mmHg (p ≤ 0.01). The new method can derive central BP more reliably than some current non-invasive devices and in the same way as traditional cuff BP.
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measurement of central aortic Pulse pressure noninvasive brachial cuff based estimation by a transfer function vs a novel Pulse wave analysis method
American Journal of Hypertension, 2012Co-Authors: Hao Min Cheng, Yuanta Shih, Shihhsien Sung, Shaoyuan Chuang, Wenchung Yu, Chen-huan ChenAbstract:BACKGROUND: The prognostic value of central aortic Pulse pressure (PP-C) may have been underestimated due to its measurement inaccuracy. We aimed to investigate the accuracy of noninvasive brachial cuff-based estimation of PP-C by a generalized transfer function (GTF) or a novel Pulse wave analysis (PWA) approach to directly estimate PP-C. METHODS: Invasive high-fidelity right brachial and central aortic pressure tracings, and left brachial Pulse Volume plethysmography (PVP) waveforms from an oscillometric blood pressure (BP) monitor were all digitized simultaneously in 40 patients during cardiac catheterization. An aortic-to-brachial GTF and a PWA multivariate prediction model using the PVP waveforms calibrated to brachial cuff systolic BP (SBP) and diastolic BP(DBP) were constructed. Accuracy of the two methods was examined in another 100 patients against invasively measured PP-C. RESULTS: The error of cuff PP in estimating PP-C was 1.8 ± 12.4 mm Hg. Application of the GTF on noninvasively calibrated PVP waveforms produced reconstructed aortic pressure waves and PP-C estimates with errors of -3.4 ± 11.6 mm Hg (PP-C = reconstructed aortic SBP - aortic DBP) and -2.3 ± 11.4 mm Hg (PP-C = reconstructed aortic SBP - cuff DBP), respectively. The observed systematic errors were proportional to the magnitudes of PP-C. In contrast, the error of the PWA prediction model was 3.0 ± 7.1 mm Hg without obvious proportional systematic error. CONCLUSIONS: Large random and systematic errors are introduced into the PP-C estimates when PP-C is calculated as the difference between the estimated central SBP and central or cuff DBP. The accuracy can be improved substantially with the novel PWA approach.
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measurement of central systolic blood pressure by Pulse Volume plethysmography with a noninvasive blood pressure monitor
American Journal of Hypertension, 2012Co-Authors: Hao Min Cheng, Kangling Wang, Yinghwa Chen, Yuanta Shih, Shihhsien Sung, Shaoyuan ChuangAbstract:Background Central systolic blood pressure (SBP) can be estimated by an oscillometric method developed from a Pulse Volume plethysmography (PVP) device. The present study applied this novel method to a noninvasive blood pressure monitor (NBPM). Methods We enrolled 50 patients (37 men, age range 30–84 years) referred for cardiac catheterization. Invasive right brachial and central aortic pressures (using a dual-sensor pressure catheter), and noninvasive left brachial SBP and diastolic blood pressure (DBP), and PVP waveform (using a customized NBPM) were simultaneously recorded. Central SBP was estimated by analysis of the PVP waveform calibrated to the noninvasive SBP and DBP, using both the original (CSBP-O) and the newly generated (CSBP-N) regression equations. The reproducibility of the invasive central SBP by CSBP-O and CSBP-N was examined using the concordance correlation coefficient. results Overall, the invasive central aortic SBP ranged 86–176 with a mean of 124 ± 21 mm Hg. The mean differences between the estimated and the invasive central SBP were −1.3 ± 6.7 mm Hg for CSBP-O and 0.0 ± 6.2 mm Hg for CSBP-N, respectively. The concordance correlation coefficients for CSBP-O and CSBP-N were 0.94 (95% confidence interval (CI): 0.93–0.94) and 0.95 (95% CI: 0.95–0.96), and both were significantly better than that for the noninvasive brachial SBP (0.87, 0.84–0.91) indicated by non-overlapping CIs. conclusions The PVP method for noninvasive estimation of central SBP can be applied to a commonly used NBPM. Whether the NBPM-derived central SBP is superior to the noninvasive brachial SBP in the prediction of cardiovascular risks remains to be investigated.
Hiroyuki Konno - One of the best experts on this subject based on the ideXlab platform.
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intraoperative monitoring of penile and buttock blood flow during endovascular abdominal aortic aneurysm repair
European Journal of Vascular and Endovascular Surgery, 2006Co-Authors: Kazunori Inuzuka, Hiroshi Mitsuoka, Kei Ishimaru, Daisuke Sagara, Naoki Unno, Minoru Suzuki, Naoto Yamamoto, Hiroyuki KonnoAbstract:Abstract Objective The purpose of this study was to assess the pelvic circulation during endovascular abdominal aortic aneurysm repair (EVAR) with a new monitoring system measuring penile and buttock blood flow. Methods We measured penile brachial pressure index (PBI) during EVAR by Pulse-Volume-plethysmography (form PWV/ABI™). We also measured bilateral gluteal tissue oxygen metabolism with near-infrared spectroscopy to provide a gluteal tissue oxygenation index (TOI). Twenty-two men who underwent aortouni-iliac stentgraft with crossover bypass for exclusion of abdominal aortic aneurysm were studied. Twelve patients underwent aorto-uni-common iliac artery stentgraft (CIA) and ten underwent aorto-uni-external iliac artery stentgraft (EIA). Results In all patients, there was an immediate reduction in PBI during the EVAR procedure. After revascularization of the ipsilateral limb of the stent graft, the recovery of PBI was significantly less in EIA group. After the completion of crossover bypass, PBI in both groups recovered to the baseline values. In both groups there was a bilateral reduction in gluteal TOI during malperfusion of the internal iliac artery. After revascularization of ipsilateral limb of the stent graft, the ipsilateral TOI recovered to the baseline level in CIA patients, but recovery was incomplete in EIA patients. In contrast, contra-lateral TOI remained low in both groups after revascularization of ipsilateral limb of the stent graft. Only after completion of crossover bypass did the contra-lateral TOI recover to baseline level in both groups. Conclusions Both TOI at the buttocks and PBI are a sensitive reflection of pelvic haemodynamics. Penile blood flow and bilateral gluteal blood flow are supplied via different circulations and both should be monitored for full assessment of the pelvic circulation.
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intraoperative monitoring of penile and buttock blood flow during endovascular abdominal aortic aneurysm repair
European Journal of Vascular and Endovascular Surgery, 2006Co-Authors: Kazunori Inuzuka, Hiroshi Mitsuoka, Kei Ishimaru, Daisuke Sagara, Naoki Unno, Minoru Suzuki, Naoto Yamamoto, Hiroyuki KonnoAbstract:OBJECTIVE: The purpose of this study was to assess the pelvic circulation during endovascular abdominal aortic aneurysm repair (EVAR) with a new monitoring system measuring penile and buttock blood flow. METHODS: We measured penile brachial pressure index (PBI) during EVAR by Pulse-Volume-plethysmography (form PWV/ABItrade mark). We also measured bilateral gluteal tissue oxygen metabolism with near-infrared spectroscopy to provide a gluteal tissue oxygenation index (TOI). Twenty-two men who underwent aortouni-iliac stentgraft with crossover bypass for exclusion of abdominal aortic aneurysm were studied. Twelve patients underwent aorto-uni-common iliac artery stentgraft (CIA) and ten underwent aorto-uni-external iliac artery stentgraft (EIA). RESULTS: In all patients, there was an immediate reduction in PBI during the EVAR procedure. After revascularization of the ipsilateral limb of the stent graft, the recovery of PBI was significantly less in EIA group. After the completion of crossover bypass, PBI in both groups recovered to the baseline values. In both groups there was a bilateral reduction in gluteal TOI during malperfusion of the internal iliac artery. After revascularization of ipsilateral limb of the stent graft, the ipsilateral TOI recovered to the baseline level in CIA patients, but recovery was incomplete in EIA patients. In contrast, contra-lateral TOI remained low in both groups after revascularization of ipsilateral limb of the stent graft. Only after completion of crossover bypass did the contra-lateral TOI recover to baseline level in both groups. CONCLUSIONS: Both TOI at the buttocks and PBI are a sensitive reflection of pelvic haemodynamics. Penile blood flow and bilateral gluteal blood flow are supplied via different circulations and both should be monitored for full assessment of the pelvic circulation.
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automated bedside measurement of penile blood flow using Pulse Volume plethysmography
Surgery Today, 2006Co-Authors: Naoki Unno, Hiroshi Mitsuoka, Kei Ishimaru, Kazunori Inuzuka, Daisuke Sagara, Hiroyuki KonnoAbstract:Purpose To evaluate the efficiency of the form PWV/ABI (Pulse wave velocity/ankle brachial pressure index) for measuring penile blood pressure (PBP) and the penile brachial pressure index (PBI).
Kangling Wang - One of the best experts on this subject based on the ideXlab platform.
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measurement of central systolic blood pressure by Pulse Volume plethysmography with a noninvasive blood pressure monitor
American Journal of Hypertension, 2012Co-Authors: Hao Min Cheng, Kangling Wang, Yinghwa Chen, Yuanta Shih, Shihhsien Sung, Shaoyuan ChuangAbstract:Background Central systolic blood pressure (SBP) can be estimated by an oscillometric method developed from a Pulse Volume plethysmography (PVP) device. The present study applied this novel method to a noninvasive blood pressure monitor (NBPM). Methods We enrolled 50 patients (37 men, age range 30–84 years) referred for cardiac catheterization. Invasive right brachial and central aortic pressures (using a dual-sensor pressure catheter), and noninvasive left brachial SBP and diastolic blood pressure (DBP), and PVP waveform (using a customized NBPM) were simultaneously recorded. Central SBP was estimated by analysis of the PVP waveform calibrated to the noninvasive SBP and DBP, using both the original (CSBP-O) and the newly generated (CSBP-N) regression equations. The reproducibility of the invasive central SBP by CSBP-O and CSBP-N was examined using the concordance correlation coefficient. results Overall, the invasive central aortic SBP ranged 86–176 with a mean of 124 ± 21 mm Hg. The mean differences between the estimated and the invasive central SBP were −1.3 ± 6.7 mm Hg for CSBP-O and 0.0 ± 6.2 mm Hg for CSBP-N, respectively. The concordance correlation coefficients for CSBP-O and CSBP-N were 0.94 (95% confidence interval (CI): 0.93–0.94) and 0.95 (95% CI: 0.95–0.96), and both were significantly better than that for the noninvasive brachial SBP (0.87, 0.84–0.91) indicated by non-overlapping CIs. conclusions The PVP method for noninvasive estimation of central SBP can be applied to a commonly used NBPM. Whether the NBPM-derived central SBP is superior to the noninvasive brachial SBP in the prediction of cardiovascular risks remains to be investigated.
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estimation of central systolic blood pressure using an oscillometric blood pressure monitor
Hypertension Research, 2010Co-Authors: Hao Min Cheng, Kangling Wang, Yinghwa Chen, Shingjong Lin, Lungching ChenAbstract:Current noninvasive techniques for assessing central aortic pressure require the recording of an arterial pressure wave using a high-fidelity applanation tonometer. We therefore developed and validated a novel method to estimate the central aortic systolic pressure using an oscillometric blood pressure monitor alone. Invasive high-fidelity right brachial and central aortic pressure waves, and left-brachial Pulse Volume plethysmography from an oscillometric blood pressure monitor, were obtained at baseline and 3 min after administration of sublingual nitroglycerin in 100 patients during cardiac catheterization. In the initial 50 patients (Generation Group), Central systolic blood pressure was predicted by a multi-variate prediction model generated from the comprehensive analysis of the invasive brachial pressure wave, including brachial late-systolic shoulder pressure value and parameters related to wave reflection and arterial compliance. Another prediction model was similarly constructed from the noninvasively calibrated Pulse Volume plethysmography. Both models were validated in the subsequent 50 patients (Validation Group) with results: r=0.98 (P<0.001) and mean difference=0.5+/-4.5 (95% confidence interval -8.3 to 9.3) mm Hg for the invasive model, and r=0.93 (P<0.001) and mean difference=-0.1+/-7.6 (95% confidence interval -15.0 to 14.8) mm Hg for the noninvasive model. Thus, our results indicate that central aortic systolic blood pressure could be estimated by analysis of the noninvasive brachial pressure wave alone from an oscillometric blood pressure monitor.
