Blood Pressure Measurement Devices Research Articles

Improved agreement and diagnostic accuracy of a cuffless 24-h blood pressure measurement device in clinical practice

A cuffless blood pressure (BP) device (TestBP) using pulse transit time is in clinical use, but leads to higher BP values compared to a cuff-based 24 h-BP reference device (RefBP). We evaluated the impact of a recent software update on BP results and TestBP’s ability to differentiate between normo- and hypertension. 71 individuals had TestBP (Somnotouch-NIBP) and RefBP measurements simultaneously performed on either arm. TestBP results with software version V1.5 were compared to V1.4 and RefBP. Mean 24 h (± SD) BP for the RefBP, TestBP-V1.4 and TestBP-V1.5 were systolic 134.0 (± 17.3), 140.8 (± 20) and 139.1 (± 20) mmHg, and diastolic 79.3 (± 11.7), 85.8 (± 14.1) and 83.5 (± 13.0) mmHg, respectively (p-values < 0.001). TestBP-V1.5 area under the curve (95% confidence interval) versus RefBP for hypertension detection was 0.92 (0.86; 0.99), 0.94 (0.88; 0.99) and 0.77 (0.66; 0.88) for systolic and 0.92 (0.86; 0.99), 0.92 (0.85; 0.99) and 0.84 (0.74; 0.94) for diastolic 24 h, awake and asleep BP respectively. TestBP-V1.5 detected elevated systolic/diastolic mean 24 h-BP with a 95%/90% sensitivity and 65%/70% specificity. Highest Youden’s Index was systolic 133 (sensitivity 95%/specificity 80%) and diastolic 87 mmHg (sensitivity 81%/specificity 98%). The update improved the agreement to RefBP. TestBP was excellent for detecting 24 h and awake hypertensive BP values but not for asleep BP values.

Office blood pressure measurement: A comprehensive review.

The conventional auscultatory methods for measuring blood pressure have been used to screen, diagnose, and manage hypertension since long. However, these have been found to be prone to errors especially the white coat phenomena which cause falsely high blood pressure readings. The Mercury sphygmomanometer and the Aneroid variety are no longer recommended by WHO for varying reasons. The Oscillometric devices are now recommended with preference for the Automated Office Blood Pressure measurement device which was found to have readings nearest to the Awake Ambulatory Blood Pressure readings. The downside for this device is the cost barrier. The alternative is to use the simple oscillometric device, which is much cheaper, with the rest and isolation criteria of the SPRINT study. This too may be difficult due to space constraints and the post‐clinic blood measurement is a new concept worth further exploration.

Prevalence of postural hypotension in primary, community and institutional care: a systematic review and meta-analysis

BackgroundPostural hypotension (PH), the reduction in blood pressure when rising from sitting or lying 0to standing, is a risk factor for falls, cognitive decline and mortality. However, it is not often tested for in primary care. PH prevalence varies according to definition, population, care setting and measurement method. The aim of this study was to determine the prevalence of PH across different care settings and disease subgroups.MethodsSystematic review, meta-analyses and meta-regression. We searched Medline and Embase to October 2019 for studies based in primary, community or institutional care settings reporting PH prevalence. Data and study level demographics were extracted independently by two reviewers. Pooled estimates for mean PH prevalence were compared between care settings and disease subgroups using random effects meta-analyses. Predictors of PH were explored using meta-regression. Quality assessment was undertaken using an adapted Newcastle-Ottawa Scale.ResultsOne thousand eight hundred sixteen studies were identified; 61 contributed to analyses. Pooled prevalences for PH using the consensus definition were 17% (95% CI, 14–20%; I2 = 99%) for 34 community cohorts, 19% (15–25%; I2 = 98%) for 23 primary care cohorts and 31% (15–50%; I2 = 0%) for 3 residential care or nursing homes cohorts (P = 0.16 between groups). By condition, prevalences were 20% (16–23%; I2 = 98%) with hypertension (20 cohorts), 21% (16–26%; I2 = 92%) with diabetes (4 cohorts), 25% (18–33%; I2 = 88%) with Parkinson’s disease (7 cohorts) and 29% (25–33%, I2 = 0%) with dementia (3 cohorts), compared to 14% (12–17%, I2 = 99%) without these conditions (P < 0.01 between groups). Multivariable meta-regression modelling identified increasing age and diabetes as predictors of PH (P < 0.01, P = 0.13, respectively; R2 = 36%). PH prevalence was not affected by blood pressure measurement device (P = 0.65) or sitting or supine resting position (P = 0.24), however, when the definition of PH did not fulfil the consensus description, but fell within its parameters, prevalence was underestimated (P = 0.01) irrespective of study quality (P = 0.04).ConclusionsPH prevalence in populations relevant to primary care is substantial and the definition of PH used is important. Our findings emphasise the importance of considering checking for PH, particularly in vulnerable populations, to enable interventions to manage it. These data should contribute to future guidelines relevant to the detection and treatment of PH.PROSPERO:CRD42017075423.

Artificial Intelligence Based Blood Pressure Estimation From Auscultatory and Oscillometric Waveforms: A Methodological Review.

Cardiovascular disease is known as the number one cause of death globally, with elevated blood pressure (BP) being the single largest risk factor. Hence, BP is an important physiological parameter used as an indicator of cardiovascular health. The use of automated non-invasive blood pressure (NIBP) measurement devices is growing, as they can be used without expertise and BP measurement can be performed by patients at home. Non-invasive cuff-based monitoring is the dominant method for BP measurement. While the oscillometric technique is most common, some automated NIBP measurement methods have been developed based on the auscultatory technique. By utilizing (relatively) large BP data annotated by experts, models can be trained using machine learning and statistical concepts to develop novel NIBP estimation algorithms. Amongst artificial intelligence (AI) techniques, deep learning has received increasing attention in different fields due to its strength in data classification and feature extraction problems. This paper reviews AI-based BP estimation methods with a focus on recent advances in deep learning-based approaches within the field. Various architectures and methodologies proposed todate are discussed to clarify their strengths and weaknesses. Based on the literature reviewed, deep learning brings plausible benefits to the field of BP estimation. We also discuss some limitations which can hinder the widespread adoption of deep learning in the field and suggest frameworks to overcome these challenges.

Validation of the blood pressure measurement technology used in the Novacor Diasys 3 (DIS-0001-00) upper arm device for ambulatory blood pressure measurement, according to the requirements of the AAMI/ANSI/ISO 81060-2:2013 standard (for both a general study and a cardiac-stress study in adults) and of the European Society of Hypertension International Protocol revision 2010.

The objective of this study was to determine the accuracy of the oscillometric blood pressure measurement technology of the Novacor Diasys 3 (model number DIS-0001-00) blood pressure monitor, intended for ambulatory blood pressure measurement, when used with the recommended Standard (ACC-0213-00), Large (ACC-0214-00) and Paediatric (ACC-0215-00) cuffs. The Novacor Diasys 3 (model number DIS-0001-00) was evaluated according to the requirements of the AAMI/ANSI/ISO 81060-2:2013 standard, including an additional cardiac-stress study, a requirement for ambulatory blood pressure measurement devices. It was also validated according to the requirements of the European Society of Hypertension International Protocol revision 2010. The protocol requirements for all thee studies were followed precisely. The Novacor Diasys 3 (model number DIS-0001-00) fulfilled all of the requirements for a pass in each of the three studies. In the primary AAMI/ANSI/ISO 81060-2:2013 study, the Criterion 1 errors were +3.9 mmHg ± 2.9 mmHg for SBP and +3.4 ± 2.5 mmHg for DBP. The Novacor Diasys 3 (model number DIS-0001-00), when used with the recommended cuffs, can be recommended for ambulatory blood pressure measurement in the adult population.

A Blood Pressure Prediction Method Based on Imaging Photoplethysmography in combination with Machine Learning

This paper proposes a non-contact blood pressure implement (NCBP) system based on imaging photoplethysmography (IPPG) The system collects facial videos through a webcam under ambient light, and extracts pulse wave signals from the videos by means of IPPG technology. From the signals (also called IPPG signals), we extracted 26 features for estimating blood pressure (BP), and trained them through four machine learning algorithms. Finally, we selected the most accurate model for blood pressure prediction. By experimenting on 191 volunteers and comparing four models, support vector regression (SVR) is the best model for predicting blood pressure. The results of SVR are that the standard deviation (STD) and mean absolute error (MAE) of systolic blood pressure (SBP) are 3.35 mmHg, 9.97 mmHg, and those of diastolic blood pressure (DBP) are 2.58 mmHg, 7.59 mmHg respectively. We conclude that through our proposed system based on IPPG technology, blood pressure can be accurately predicted in a non-contact way. In addition, this paper proposes two new methods, the region of interest (ROI) selection method based on colormaps and robust peak extraction method, which solve the key steps in IPPG technology. Finally, we discussed the influence of light intensity on the experiment, and simplified the NCBP experimental device. The system has the potential of replacing the traditional cuff-based sphygmomanometers, and has guiding significance to the future development of blood pressure measurement devices.

The capacity of primary health care centers in Jordan to manage hypertension: areas for improvement.

The assessment of the capacity of Primary Health Care (PHC) settings for the management of hypertension is essential to identify areas for improving management outcomes. This study aimed to assess the capacity of PHC centers in Jordan to manage hypertension including the assessment of human resources, equipment, and infrastructure. All comprehensive PHC centers located in Irbid and Mafraq governorates in north of Jordan (n = 23) were assessed. An assessment tool from HEARTS Technical Package was adapted and used for assessment. All centers have general practitioners and half of the centers (n = 11, 47.8%) had at least one family doctor working full time. In only one center, all doctors, nurses, and other health workers were trained on the management of hypertension. All centers, except one, had at least one functional automatic blood pressure measuring devices (BPMDs). Almost two thirds of centers (43.5%) had no measuring tapes. ECG machines were present in all centers except two. One third (n = 8, 34.8%) of centers had no functional glucometers. The majority of health centres carry out the laboratory investigations. Educational materials on physical activity, hypertension, and diabetes were seen in four (17.4%) centers only. Necessary medications were always available in the majority of health centers. In conclusion, this assessment revealed many areas for improvement in human resources, equipment, infrastructures, and other resources, such as developing an updated guideline/protocol of hypertension management, training the PHC staff on these guidelines, providing PHC centers with the necessary equipment, and establishing e-registry to improve documentation of data.

Validation of the blood pressure measurement technology used in the Novacor Diasys 3 Plus (DIP-0001-00) upper-arm device for ambulatory blood pressure measurement, according to AAMI/ANSI/ISO 81060-2: 2013, ESH-IP 2010 and MEDDEV 2.7/1.

The objective of this study was to determine the accuracy of the auscultatory and oscillometric blood pressure (BP) measurement technologies of the Novacor Diasys 3 Plus (model number DIP-0001-00) BP monitor, intended for ambulatory BP measurement when used with the recommended Standard Plus (ACC-0210-00), Large Plus (ACC-0211-00) and Paediatric Plus (ACC-0212-00) cuffs. The auscultatory measurement technology Novacor Diasys 3 Plus (model number DIP-0001-00) was evaluated according to the requirements of the AAMI/ANSI/ISO 81060-2:2013 standard, including an additional cardiac-stress study, a requirement for ambulatory BP measurement devices. It was also validated according to the requirements of the European Society of Hypertension International Protocol revision 2010. The oscillometric measurement technology was compared to that of the Novacor Diasys 3 (model number DIS-0001-00) according to the equivalence requirements of MEDDEV 2.7/1 rev 4. The protocol requirements for all three studies and the equivalence were followed precisely. The Novacor Diasys 3 Plus (model number DIP-0001-00) fulfilled all of the requirements for a pass in each of the three studies of the auscultatory measurement technology. In the primary AAMI/ANSI/ISO 81060-2:2013 study, the criterion 1 errors were + 3.6 ± 2.7 mmHg for SBP and + 3.0 ± 2.7 mmHg for DBP. It was also proven to be equivalent to the Novacor Diasys 3 (model number DIS-0001-00) with respect to the oscillometric measurement technology CONCLUSION: The Novacor Diasys 3 Plus (model number DIP-0001-00), when used with the recommended cuffs, can be recommended for ambulatory BP measurement in the adult population.

Blood pressure measurement methodology and technology in the SWEET diabetes centers: An international SWEET database survey

The accuracy of blood pressure (BP) measurement is a prerequisite for the reliable diagnosis and management of hypertension. This survey evaluated the use of office and out-of-office BP measurements and the antihypertensive pharmacological treatment in expert pediatric diabetes centers. A questionnaire was distributed in 78 reference pediatric diabetes centers of the SWEET international consortium. The methodology, devices, indications, and interpretation of office BP measurements (OBPM), 24-hour ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM), and the preference for antihypertensive drug treatment was assessed. A grading score was developed to evaluate centers for overall BP measurement performance. Fifty-two centers responded. The average score for OBPM methodology was 72.5%, for technology 77.5% and the overall center score was 74.75%.The majority of the centers used appropriate methodology and technology, however, there was heterogeneity among them. Manual auscultatory or automated devices specifically validated for children were used by 26/52 centers. ABPM was recommended by 35/52 centers (27/35 had health insurance coverage) and HBPM by 18/52 centers. The BP measurement methodology and devices used for ABPM and HBPM were frequently inadequate. Angiotensin converting enzyme inhibitors were the most frequently prescribed drugs for treating hypertension. The majority of SWEET pediatric diabetes centers use adequate methodology and devices for BP measurement. ABPM is recommended by two thirds of the centers, whereas HBPM is less widely used. Further improvement in the quality of office and out-of-office BP measurements and harmonization among centers is necessary according to current guidelines.

Results of a project to calibrate mercury sphygmomanometer blood pressure-measuring devices in Egypt

Hypertension (HTN) is a common health problem and a major cardiovascular risk factor. Accurate measurement of blood pressure (BP) is mandatory for proper diagnosis and follow-up. The aim of this study was to evaluate the accuracy of mercury sphygmomanometer BP-measuring devices in public hospitals in Cairo, Egypt. Fifty public hospitals were included, and 10% of all mercury sphygmomanometer devices in each hospital were tested. Assessment included physical condition (e.g., mercury status, lid of the device, state of the rubber tubes), leakage rate, and calibration accuracy (as compared with a reference device). Devices were approved as accurate when they could successfully pass all three assessment tests. The total number of sphygmomanometer devices was 465. The overall pass rate was 1.3% (six devices). Twenty-five (5.2%) devices passed all of the physical tests, 50 (10.8%) passed the leakage test, and 50 (16.5%) passed the calibration accuracy test. There were 162 (34.8%) devices that showed a high leakage rate (>80 mmHg) and thus were not tested for calibration accuracy. In conclusion, most of the mercury sphygmomanometer devices in hospitals are neglected and not checked regularly for any errors. A plan should be made to gradually replace those failed devices with new, validated, and well-calibrated devices, preferably devices that do not contain mercury.

Performance of an automated blood pressure measurement device in a stroke rehabilitation unit

Valid blood pressure (BP) measurements are needed in post-stroke rehabilitation hospital units for the management of hypertension. Automated devices could be used to improve on usual care BP measurement. However, more information is needed about the performance of these devices in such a context. This prospective nonrandomized study was performed in stroke patients with hypertension hospitalized in a stroke rehabilitation unit. Two in-hospital BP assessment strategies were compared: usual care BP and in-hospital automated office BP (AOBP) standardized measurements. In-office AOBP and ambulatory BP monitoring (ABPM) were also performed on these patients. The main outcome was SBP. Study follow-up was until discharge, up to a maximum of 4 weeks. Sixty-two patients with stroke hospitalized in a rehabilitation unit were included. Usual care BP was 130 ± 12/79 ± 9 mmHg and differed from an in-hospital AOBP of 117 ± 14/75 ± 12 mmHg (P < 0.001/P < 0.001). In-hospital and in-office AOBP measurements did not differ. Twenty percent of patients reached SBP therapeutic goals according to in-hospital AOBP but not according to usual care BP measurements. This study shows that in a post-stroke rehabilitation unit, standardized in-hospital AOBP estimates are on average much lower than the usual care BP correlates and similar to the in-office AOBP estimates. In-hospital AOBP devices in a stroke rehabilitation unit could add important information for the management of hypertension.

Preliminary assessment of video-based blood pressure measurement according to ANSI/AAMI/ISO81060-2: 2013 guideline accuracy criteria: Anura smartphone app with transdermal optimal imaging technology.

A new smartphone app called Anura can measure blood pressure (BP) any time and any place without cuffs or special equipment from video of the face. This study assessed its accuracy in close conformity with the American National Standards Institute/Association for the Advancement of Medical Instrumentation/International Organization for Standardization (ANSI/AAMI/ISO) 81060-2:2013 standard for BP measurement devices. We validated Anura in reference to auscultation using a mercury sphygmomanometer and then assessed accuracy against the two accuracy criteria described in the guideline (n = 85 subjects; three measurement pairs per subject). The mean difference between the Anura measurement and its paired auscultatory reference measurement across all 255 measurement pairs was -0.4 ± 6.7 mmHg for systolic blood pressure (SBP) and 1.2 ± 7.0 mmHg for diastolic blood pressure (DBP). Both are within the acceptable limit of 5 ± 8 mmHg and thus satisfy accuracy criterion 1. When mean differences are averaged for each subject, the mean across all 85 subjects is -0.4 ± 5.8 mmHg for SBP and 1.2 ± 6.7 mmHg for DBP. Both are within acceptable limits (based on the mean difference) and thus satisfy accuracy criterion 2. Anura meets ANSI/AAMI/ISO 81060-2:2013 standard with respect to BP measurement accuracy. As the ANSI/AAMI/ISO 81060-2:2013 standard has not been developed for cuffless devices, further research assessing additional accuracy issues specific to such devices is needed.

Development of a noninvasive instantaneous blood pressure measurement device based on volume-compensation method and study of its control algorithm

An instantaneous blood pressure measurement device based on volume compensation was developed, and a measurement control method was tested and improved on the device. The device consists of a cylindrical finger cuff, a compact proportional solenoid valve, an air pump and a hardware circuit. Finger cuff contains a pair of led and photo-diode. The hardware circuit consists of a feedback controls circuit and a signal processing circuit based on a microprocessor controller. A neural network predictive controller is proposed to replace the traditional PID controller for experiments. Simulation and experiments show that the neural network predictive controller has better control effect than the traditional PID controller.

A Novel Automated Blood Pressure Estimation Algorithm Using Sequences of Korotkoff Sounds.

The use of automated non-invasive blood pressure (NIBP) measurement devices is growing, as they can be used without expertise, and BP measurement can be performed by patients at home. Non-invasive cuff-based monitoring is the dominant method for BP measurement. While the oscillometric technique is most common, a few automated NIBP measurement methods have been developed based on the auscultatory technique. Amongst artificial intelligence (AI) techniques, deep learning has received increasing attention in different fields due to its strength in data classification, and feature extraction problems. This paper proposes a novel automated AI-based technique for NIBP estimation from auscultatory waveforms (AWs) based on converting the NIBP estimation problem to a sequence-to-sequence classification problem. To do this, a sequence of segments was first formed by segmenting the AWs, and their corresponding decomposed detail, and approximation parts obtained by wavelet packet decomposition method, and extracting features from each segment. Then, a label was assigned to each segment, i.e. (i) between systolic, and diastolic segments, and (ii) otherwise, and a bidirectional long short term memory recurrent neural network (BiLSTM-RNN) was devised to solve the resulting sequence-to-sequence classification problem. Adopting a 5-fold cross-validation scheme, and using a data base of 350 NIBP recordings gave an average mean absolute error of 1.7±3.7 mmHg for systolic BP (SBP), and 3.4 ±5.0 mmHg for diastolic BP (DBP) relative to reference values. Based on the results achieved, and comparisons made with the existing literature, it is concluded that the proposed automated BP estimation algorithm based on deep learning methods, and auscultatory waveform brings plausible benefits to the field of BP estimation.

Comparison of Doppler ultrasonic and oscillometric devices (with or without proprietary optimisations) for non-invasive blood pressure measurement in conscious cats.

ObjectivesThis study compared Doppler and oscillometric (PetMAP+) devices (with or without proprietary optimisations) for the non-invasive measurement of blood pressure in conscious cats.MethodsTwenty-three cats were enrolled; however, five were excluded as fewer than five measurements were obtained for each assessment. All measurements were obtained according to American College of Veterinary Internal Medicine consensus guidelines. Oscillometric device modes A and B were operated according to the manufacturer’s guidelines. Doppler and oscillometric devices were used alternately as the first device.ResultsSystolic arterial blood pressure (SAP) measurements were obtained by Doppler (SAPd) and oscillometry; the mean of each set of five values was used for statistical analysis. There was a significant difference between SAPd and SAP measurements in oscillometric modes A (P <0.001) and B (P <0.001). While both modes measured SAP higher than SAPd, B had a smaller bias (+15.72 mmHg) and narrower limits of agreement (LOA). There was also a significant difference between SAPd and mean arterial pressure (MAP) on oscillometric modes A (P = 0.002) and B (P <0.001). Both modes’ MAP readings were lower than SAPd and oscillometric A MAP was closer to SAPd (–14.94 mmHg), with a smaller bias and narrower LOA.Conclusions and relevanceThe findings support that Doppler and oscillometric devices cannot be used interchangeably, with or without proprietary optimisations. Methodology should always be taken into account and reference intervals (RIs) need to be defined for the different methodologies. Until methodology-specific RIs are published, definitive diagnosis of hypertension and sub-staging of patients with kidney disease according to the International Renal Interest Society guidelines remains challenging.

PCA-Based Multi-Wavelength Photoplethysmography Algorithm for Cuffless Blood Pressure Measurement on Elderly Subjects.

The prevalence of hypertension has made blood pressure (BP) measurement one of the most wanted functions in wearable devices for convenient and frequent self-assessment of health conditions. The widely adopted principle for cuffless BP monitoring is based on arterial pulse transit time (PTT), which is measured with electrocardiography and photoplethysmography (PPG). To achieve cuffless BP monitoring with more compact wearable electronics, we have previously conceived a multi-wavelength PPG (MWPPG) strategy to perform BP estimation from arteriolar PTT, requiring only a single sensing node. However, challenges remain in decoding the compounded MWPPG signals consisting of both heterogeneous physiological information and motion artifact (MA). In this work, we proposed an improved MWPPG algorithm based on principal component analysis (PCA) which matches the statistical decomposition results with the arterial pulse and capillary pulse. The arteriolar PTT is calculated accordingly as the phase shift based on the entire waveforms, instead of local peak lag time, to enhance the feature robustness. Meanwhile, the PCA-derived MA component is employed to identify and exclude the MA-contaminated segments. To evaluate the new algorithm, we performed a comparative experiment (N = 22) with a cuffless MWPPG measurement device and used double-tube auscultatory BP measurement as a reference. The results demonstrate the accuracy improvement enabled by the PCA-based operations on MWPPG signals, yielding errors of 1.44 ± 6.89 mmHg for systolic blood pressure and -1.00 ± 6.71 mm Hg for diastolic blood pressure. In conclusion, the proposed PCA-based method can improve the performance of MWPPG in wearable medical devices for cuffless BP measurement.

Blood Pressure Estimation Algorithm Based on Photoplethysmography Pulse Analyses

Though small wrist-type blood pressure (BP) measurement devices using simple sensors have recently been developed, they lack accuracy and require the input of personal user data. To miniaturize BP measurement devices, this study proposes the use of algorithms that can calculate BP using sensors that utilize only two photoplethysmographies (PPGs), without the need for electrocardiograms. To reduce the error of indirect BP measurement, specific values representing individual blood vessel conditions are improved via the application of an algorithm developed using mean arterial pressure and PPG phase difference. To reduce the error that occurs when measuring BP using PPG, a specific value algorithm used to develop a miniaturized BP measuring device using two PPGs is proposed along with a new model. The developed ultra-small PPG measuring device uses a reflective photoplethysmography measurement circuit. This is presented as a PPG-only model that deviates from the method of additionally linking existing electrocardiography (ECG). The measurement device developed in this study is compared with the air-pressurized automatic BP measurement device in terms of the BP measurement value; the result of maintaining the error stably at 5% is derived to prove the superiority of the algorithm.

How reliable are the current Blood Pressure Measuring devices in Health Facilities of Bhutan?

Background: Accurate blood pressure measurement is vital before any inferences are made on the reading. Since device error is one of the potential causes of inaccurate results, blood pressure measuring (BPM) devices should be periodically assessed for its accuracy. This paper describes the types of BPM devices used in health facilities of Bhutan and the results of their performance verifications. Method: This study assessed the pressure accuracy and leak rates of BPM devices in use at two regional referral hospitals, district hospitals and BHU I using calibrated Vital Signs Simulator (ProSimTM 8) from Fluke Biomedical as reference device. For pressure accuracy assessment, static pressures were simulated against which simultaneous readings of each of the devices were recorded (n=3). For the leak rate assessment, the simulator was set to a target pressure and leak rate (n=3) were recorded over 1 minute. Result: A total of 395 devices of three types, viz., 135 aneroid, 125 electronic and 135 mercury were assessed. Deviations in readings of 64.72% of devices were found to be within acceptable range of ± 3 mmHg. The device-type specific pass percentages for pressure accuracy were 6.40 % for electronic, 88.81 % for aneroid and 94.81 % for mercury. A total of 71.85% of devices (aneroid and mercury) had acceptable leak rates of 15 mmHg per minute. Conclusion: The study shows that not all the blood pressure measuring devices currently being used in the health facilities of Bhutan are accurate. Besides ensuring that only validated BPM devices enter the country, these devices should be verified for its performance periodically once they are in use.

MON-LB52 Evaluation of Arterial Stiffness in Acromegaly Patients

Acromegaly is associated with increased morbidity and mortality primarily attributed to cardiovascular and cerebrovascular diseases, thus demonstrating the negative arterial impact of chronic GH and IGF-1 excess. There are limited and conflicting data regarding coronary artery disease (CAD) in acromegaly that consists mainly of heterogeneous cohorts and pathological reviews of old case series. Increased arterial stiffness is associated with an increased risk of cardiovascular events such as myocardial infarction. Arterial stiffness may measured from pulse wave velocity(PWV). In this study we aimed to evaluate the association between pulse wave velocity and aortic augmentation index in acromegalic patients. Methods: Our study population consists of a consecutive subset of 32 acromegalic patients and 19 control. Acromegalic patients IGF 1 levels were noted. All patients BMI, age, blood pressure, gender also were noted. Also pulse pressure, central blood pressures were measured by non-invasive central blood pressure measurement device (SphygmoCor). Pulse wave velocity and aortic augmentation index were measured by the same device. Results: A total of 32 acromegalic patients and 19 control were enrolled in the study. Body mass index and gender were not significantly different between the groups. Aortic augmentation index (5 vs. 6, p =0,685) variables weren’t significantly different in the study. Systolic and diastolic blood pressures were significantly high in the acromegalic group. (130/82 vs. 120/70) PWV was significantly high in the acromegalic group. (13 vs 11,5 p=0,002)Conclusions: Our study results suggest that acromegaly patients have worse arterial stiffness due to increased pulse wave velocity. Acromegaly is associated with increased morbidity and mortality primarily attributed to cardiovascular problems. We thought that it may be a guiding method in disease management since it can be an early marker of cardiovascular risk.Keywords: acromegaly, pulse wave velocity, aortic augmentation index

Blood pressure measurement device selection in low-resource settings: Challenges, compromises, and routes to progress.

High blood pressure (BP) is the single leading preventable cardiovascular disease (CVD) risk factor across the world. In order to decrease the global burden of CVD, broad hypertension screening programs that facilitate early hypertension diagnosis and treatment are essential. Accurate BP devices are a key element of hypertension control programs. With the overwhelming number of devices available now on the market, most of which have not been tested for accuracy, it can be challenging to select the optimal BP measurement device for clinical settings. This review details essential factors to consider when selecting a good-quality BP device, particularly for use in low-resource settings. Barriers to the procurement and use of good-quality devices are reviewed and practical solutions proposed.