Detection of peripheral arterial disease with an improved automated device: comparison of a new oscillometric device and the standard Doppler method

Cardiovascular health and target end-organ damage and comorbidities in hypertensive patients from a Spanish primary care urban population

We hypothesized that a poorer cardiovascular health status is related to a higher risk of hypertension-mediated organ-damage (HMOD) or hypertension-related comorbidities (HRC). We assessed the relationship between cardiovascular health metrics (CVHM) and HMOD-HRC in 243 hypertensive patients from primary care center followed for two years. We recorded the baseline CVHM score (Life's Simple 7) plus clinical data, including prevalent and incident HMOD-HRC, hospitalization and mortality. The prevalence of ideal CVHM scores was very low in both men and women. The patients with healthier CVHM scores were younger, and had a lower prevalence of diabetes, cardiovascular disease and chronic kidney disease. We recorded 264 cases of HMOD-HRC (225 at baseline and 39 during follow-up). Nine patients died and 64 had any-cause hospitalization during follow-up. A lower prevalence of HMOD-HRC and unfavorable outcomes was observed as the number of ideal CVHM increased (P<0.05). Multivariate logistic regression adjusted for confounders showed a lower CVHM score (0-1) was associated with increased odds of HMOD-HRC (4.04, 95% CI 1.26-12.94; P=0.019) and composite endpoint (HMOD-HRC, death or all-cause hospitalization) (3.43, 95% CI 1.19-9.92; P=0.023). Individual components were less predictive than the cumulative CVHM score. Few hypertensive patients in this urban population had ideal CVHM scores. An inverse relationship between scores and outcomes (HMOD-HRC, death or hospitalizations) was observed. Interventions to increase this score may improve prognosis among community-based hypertensive patients.

A cross-sectional study in type 2 diabetes patients reveals that elevated pulse wave velocity predicts asymptomatic peripheral arterial disease associated with age and diabetes duration

Background

Peripheral arterial disease (PAD) reduces functional capacity and raises cardiovascular risks, but underdiagnosis is common, resulting in less comprehensive care than other cardiovascular conditions. While diabetes has long been viewed as a key risk factor for PAD, recent studies indicate that its impact is influenced by the presence of concurrent cardiovascular risk factors. The aim of this study is to elucidate the intricate relationship between the prevalence of PAD, diabetic complications, and cardiovascular risk factors among asymptomatic patients with type 2 diabetes mellitus (T2DM).

Methods

Ninety-one patients with T2DM and no symptoms or previous diagnosis of PAD were recruited from the outpatient diabetic clinic. Clinical data were extracted from electronic medical records, and the screening for PAD was conducted using MESI mTABLET.

Results

Screening for PAD among asymptomatic individuals with T2DM revealed that 5.49 % of patients exhibit a low ankle-brachial index (ABI). Patients who had previously experienced major adverse cardiovascular events or exhibited albuminuria displayed lower ABI values. Furthermore, a striking 45.05 % of the participants displayed an abnormally high carotid-femoral pulse wave velocity (cfPWV) value, with elevated PWV values correlating with advanced age and longer diabetes duration.

Conclusions

The prevalence of elevated cfPWV is more pronounced than that of decreased ABI in T2DM patients with asymptomatic PAD and is associated with older age and longer diabetes duration, therefore measurement of both ABI and PWV is crucial for the cardiovascular risk assessment protocol for patients with T2DM and timely PAD diagnosis.

Screening for Peripheral Artery Disease Using an Automated Four-Limb Blood Pressure Monitor Equipped with Toe-Brachial Index Measurement

Toe-brachial index (TBI) measurement helps to detect peripheral artery disease (PAD) in patients with incompressible ankle arteries due to medial arterial calcification, which is most frequently associated with diabetes. We aimed to evaluate how an automated four-limb blood pressure monitor equipped with TBI measurement could contribute to PAD screening. In 117 patients (mean age 63.2 ± 12.8 years), ankle-brachial index (ABI) measurement was performed using the Doppler-method and the MESI mTablet. TBI was obtained via photoplethysmography (MESI mTablet, SysToe) and a laser Doppler fluxmeter (PeriFlux 5000). Lower limb PAD lesions were evaluated based on vascular imaging. A significant correlation was found between Doppler and MESI ankle-brachial index values (r = 0.672), which was stronger in non-diabetic (r = 0.744) than in diabetic (r = 0.562) patients. At an ABI cut-off of 0.9, Doppler (AUC = 0.888) showed a sensitivity/specificity of 67.1%/97.4%, MESI (AUC 0.891) exhibited a sensitivity/specificity of 57.0%/100%; at a cut-off of 1.0, MESI demonstrated a sensitivity/specificity of 74.7%/94.8%. The TBI values measured using the three devices did not differ significantly (p = 0.33). At a TBI cut-off of 0.7, MESI (AUC = 0.909) revealed a sensitivity/specificity of 92.1%/67.5%. Combining MESI ABI and TBI measurements recognised 92.4% of PAD limbs. Using an ABI cut-off level of 1.0 and sequential TBI measurement increases the sensitivity of the device in detecting PAD. The precise interpretation of the obtained results requires some expertise.

Prospective Assessment of the Diagnostic Accuracy of Multi-site Photoplethysmography Pulse Measurements for Diagnosis of Peripheral Artery Disease in Primary Care

Peripheral arterial disease (PAD) is associated with cerebral and coronary artery disease. Symptomatic PAD affects about 5% of people over 55 years; many more have asymptomatic PAD. Early detection enables modification of arterial disease risk factors. Diagnostically, assessment of symptoms or signs can be unreliable; ankle brachial pressure index (ABPI) testing is time-consuming and few healthcare professionals are properly trained. This study assessed the diagnostic accuracy of multi-site photoplethysmography (MPPG), an alternative non-invasive test for PAD, in primary care. PAD patients identified from general practice registers were age- and sex-matched with controls. Participants were assessed using MPPG, ABPI and duplex ultrasound (DUS). Outcome measures were sensitivity and specificity of MPPG and ABPI (relative to DUS) and concordance. MPPG test results were available in 249 of 298 eligible participants from 16 practices between May 2015 and November 2016. DUS detected PAD in 101/249 (40.6%). MPPG sensitivity was 79.8% (95% confidence interval [CI] 69.9-87.6%), with specificity 71.9% (95% CI 63.7-79.2%). ABPI sensitivity was 80.2% (95% CI 70.8-87.6%), with specificity 88.6% (95% CI 82-93.5%). With comparable sensitivity to ABPI, MPPG is quick, automated and simpler to do than ABPI; it offers the potential for rapid and accessible PAD assessments in primary care.

Higher Body Mass Index is associated with increased arterial stiffness prior to target organ damage: a cross-sectional cohort study

BACKGROUND

Obesity is associated with several neurohumoral changes that play an essential role in organ damage. Increased arterial stiffness causes functional vessel wall changes and can therefore lead to accelerated target organ damage as well. Whether obesity causes an independent increase in central arterial stiffness is, however, not yet fully known.

METHODS

One hundred thirty-three patients (63.2% male) were included. Body Mass Index (BMI) was defined as body weight in kilograms, divided by the square of body height in meters. Chronic Kidney Disease Epidemiology Collaboration creatinine 2009 equation was used to estimate the glomerular filtration rate (eGFR). Non-invasive applanation tonometry was used for arterial stiffness measurements (Sphygmocor Atcor Medical, Sydney, Australia). All patients underwent coronarography.

RESULTS

The mean age of our patients was 65.0 ± 9.2 years. Their mean BMI was 28.5 ± 4.4 kg/m2, eGFR 75.5 ± 17.2 ml/min/1.73 m2 and ankle-brachial index (ABI) 1.0 ± 0.1. Their arterial stiffness measurements showed mean carotid-femoral pulse wave velocity (cfPWV) 10.3 ± 2.7 m/s, subendocardial viability ratio (SEVR) 164.4 ± 35.0%, and pulse pressure (PP) 47.8 ± 14.5 mmHg. Spearman's correlation test revealed a statistically significant correlation between BMI and SEVR (r = -0.193; p = 0.026), BMI and cfPWV (r = 0.417; p < 0.001) and between BMI and PP (r = 0.227; p = 0.009). Multiple regression analysis confirmed an independent connection between BMI and cfPWV (B = 0.303; p < 0.001) and between BMI and SEVR (B = -0.186; p = 0.040). There was no association between BMI and kidney function, ABI, or coronary artery disease.

CONCLUSION

Increased BMI is independently associated with augmented central arterial stiffness and reduced subendocardial perfusion but not with coronary artery disease, kidney function, or ABI.

Association between Cardiovascular Health, C-Reactive Protein, and Comorbidities in Spanish Urban-Dwelling Overweight/Obese Hypertensive Patients

The relationship between poorer cardiovascular health metrics (CVHM) plus low-grade inflammation (LGI) and hypertension-mediated organ damage (HMOD) and hypertension-related comorbidities (HRC) in hypertensive populations with an overweight/obese (Ow/Ob) hypertension-related phenotype is understudied. We examined the relationship between the CVHM score and the presence of LGI and Ow/Ob hypertension-associated phenotype morbidities and mortality in 243 hypertensive patients from an urban primary care center. We recorded the baseline CVHM score plus clinical data, including hs-C-reactive protein (CRP) and prevalent and incident HMOD-HRC and death. A total of 26 (10.7%) had a body mass index (BMI) < 25 kg/m², 95 (31.1%) were overweight (BMI 25-29.9 kg/m²), and 122 (50.2%) were obese (BMI ≥ 30 kg/m²). There were 264 cases of HMOD-HRC and 9 deaths. Higher hs-CRP levels were observed as BMI increased. Linear regression analysis showed a significant correlation between BMI and hs-CRP, adjusted for confounders. Additionally, individuals with a higher hs-CRP tertile had a significant increase in BMI. Significantly lower log hs-CRP levels were found as the number of ideal CVHM scores rose. Multivariate binary logistic regression found the risk of HMOD-HRC increased significantly as the ideal CVHM scores decreased, and hs-CRP levels also correlated with HMOD-HRC in the whole cohort and in the Ow and Ob subpopulations. These findings highlight the need for early intervention targeting ideal CVHMs among hypertensive individuals with an Ow/Ob phenotype in order to attenuate the inflammatory state and prevent cardiovascular disease.

Are portable ankle brachial pressure index measurement devices suitable for hypertension screening?

OBJECTIVE

In a large-scale population cardiovascular screening programme, peripheral artery disease (PAD) and hypertension would ideally be rapidly assessed using a single device. The ankle-brachial pressure index (ABPI) is calculated by comparing the ankle and brachial blood pressure (BP). However, it is currently unclear whether brachial BP measurements provided by automated PAD screening systems are sufficiently accurate for simultaneous hypertension screening.

METHODS

Two portable PAD screening devices, the MESI ABPI MD and Huntleigh's Dopplex ABIlity, were evaluated following the European Society of Hypertension International Protocol (ESH-IP) Revision 2010 using a mercury-free sphygmomanometer as a reference device.

RESULTS

On average, the MESI slightly underestimated brachial systolic blood pressure (BP) with a bias and standard deviation (SD) of -3.5 (SD: 3.3) mmHg and diastolic BP with a bias of -1.5 (SD: 2.3) mmHg. For systolic BP estimates, the Dopplex was more accurate than the MESI with a lower bias of -0.5 (SD: 4.2) mmHg but less precise. The MESI successfully fulfilled all the requirements of the ESH-IP for hypertension screening. The Dopplex device failed the ESH-IP due to the absence of DBP measurements.

CONCLUSIONS

The MESI device appears to be suitable for simultaneous PAD and hypertension screening as part of a preventative care programme. Huntleigh's Dopplex ABIlity failed to pass the ESH-IP validation test. Further clinical trials are underway to assess the use of the MESI for simultaneous screening for hypertension and PAD in a population screening setting.

Selecting Portable Ankle/Toe Brachial Pressure Index Systems for a Peripheral Arterial Disease Population Screening Programme: a Systematic Review, Clinical Evaluation Exercise, and Consensus Process

OBJECTIVE

To provide an overview of systems available for peripheral arterial disease (PAD) screening, together with respective accuracies and a clinical evaluation to identify a system suitable for use in a community screening programme.

METHODS

A systematic review of the diagnostic accuracy of six ankle brachial pressure index (ABPI) and toe brachial pressure index (TBPI) devices deemed to be portable, which were Conformité Européenne (CE) marked, and were automated or semi-automated was carried out compared with gold standard handheld Doppler and duplex ultrasound. The devices were MESI-ABPI-MD, Huntleigh Dopplex Ability, Huntleigh ABPI and TBPI systems, Systoe TBPI system, and BlueDop. Seven databases (MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Register of Controlled Trials (CENTRAL), and Cumulative Index to Nursing and Allied Health Literature (CINAHL)) were searched, and 11 studies were identified as eligible for review. This was followed by hands on clinical evaluation by abdominal aortic aneurysm (AAA) screening staff (n = 39). During this, devices were demonstrated to staff which they then tested on volunteers and gave feedback using pre-designed questionnaires on their suitability for use in a screening programme. Finally, accuracy data and staff preferences were combined during a consensus conference that was held between study and screening staff to determine the most appropriate device to use in a community screening programme.

RESULTS

Generally, the evaluated systems have a moderate level of sensitivity and a high level of specificity: Dopplex ability sensitivity 20% - 70%, specificity 86% - 96%; MESI sensitivity 57% - 74%, specificity 85% - 99%; BlueDop sensitivity 95%, specificity 89%; and Systoe sensitivity 71%, specificity 77%. Clinical evaluation by screening staff identified a preference for the MESI system. The consensus conference concluded that the MESI device was a good candidate for use in a community PAD screening programme.

CONCLUSION

The MESI system is a good candidate to consider for community PAD screening.

Abnormal ankle-brachial index, cardiovascular risk factors and healthy lifestyle factors in hypertensive patients: prospective cohort study from a primary care urban population

Background

Peripheral arterial disease (PAD) and arterial stiffness (AS) may be hypertension-mediated vascular lesions. Both are determined by an abnormal ankle-brachial index (ABI) and are predictors of cardiovascular disease (CVD) and mortality. We assessed the relationship in urban hypertensive patients between an abnormal ABI and an ideal cardiovascular health (CVH) score, plus other healthy factors, with unfavourable outcomes.

Methods

We studied 243 hypertensive patients from a primary care urban population, followed for two years. Clinical data, comorbid conditions, including hypertension-mediated organ damage (HMOD) and hypertension-related comorbidities (HRC), hospitalizations and mortality were also recorded.

Results

A low prevalence of ideal CVH was observed in urban hypertensive patients. The ABI ≤ 0.9 group (n = 16) showed a higher proportion of prior CVD other than PAD, mortality and hospitalizations than the ABI > 1.4 group (n = 41), and a poorer lipid, metabolic and renal profile. An inverse relationship between CVH score and ABI ≤ 0.9 and unfavourable outcomes (HMOD, HRC, death or hospitalization) was observed. Chronic kidney disease (CKD) and diabetes were independently associated with an ABI ≤ 0.9. Age, sex, diabetes, CKD, ABI ≤ 0.9 and ideal cholesterol were also associated with outcomes, but not other CVH metrics.

Conclusions

Besides a low prevalence of ideal CVH, an inverse relationship between CVH score and ABI ≤ 0.9 and unfavourable outcomes was observed in hypertensive patients from an urban population. Stronger efforts to promote ideal CVH may improve outcomes in this particular population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01837-1.

Automated Measurements of Ankle-Brachial Index: A Narrative Review

Peripheral artery disease (PAD) is an atherosclerotic disease that causes obstruction in lower limb arteries. It increases cardiovascular risk even in asymptomatic patients. Accurate diagnostic tools for identification of affected individuals are needed. Recently, there have been attempts to establish a reliable method of automated ankle-brachial index (ABI) identification. A search of PubMed database to identify studies assessing automatic ABI measurements in agreement with standard PAD diagnosis methods was conducted in December 2020. A total of 57 studies were analyzed in the review. The majority of analyzed studies found ABI measured by automatic oscillometric devices to be potentially feasible for use. Some note that, even though the Doppler and oscillometric methods are not fully interchangeable, the oscillometric devices could be used in screening. Significantly fewer publications are available on automatic plethysmographic devices. For photoplethysmography, most studies reported either good or moderate agreement with reference standards. For air plethysmography, poorer agreement with Doppler ABI is suggested. It is noted that pulse volume recording (PVR) function may improve the diagnostic accuracy of the devices.

Intelligent Oscillometric System for Automatic Detection of Peripheral Arterial Disease

Peripheral arterial disease (PAD) is a progressing arterial disorder that is associated with significant morbidity and mortality. The conventional PAD detection methods are invasive, cumbersome, or require expensive equipment and highly trained technicians. Here, we propose a new automated, noninvasive, and easy-to-use method for the detection of PAD based on characterizing the arterial system by applying an external varying pressure using a cuff. The superposition of the internal arterial pressure and the externally applied pressure were measured and mathematically modeled as a function of cuff pressure. A feature-based learning algorithm was then designed to identify PAD patterns by analyzing the parameters of the derived mathematical models. Genetic algorithm and principal component analysis were employed to select the best predictive features distinguishing PAD patterns from normal. A RUSBoost ensemble model using neural network as the base learner was designed to diagnose PAD from genetic algorithm selected features. The proposed method was validated on data collected from 14 PAD patients and 19 healthy individuals. It achieved a high accuracy, sensitivity, and specificity of 91.4%, 90.0%, and 92.1%, respectively, in detecting PAD. The effect of age, a confounding factor that may have impacted our analyzes, was not considered in this study. The proposed method shows promise toward noninvasive and accurate detection of PAD and can be integrated into routine oscillometric blood pressure measurements.

Familial tendency for hypertension is associated with increased vascular stiffness

OBJECTIVE

Hypertension is the leading cause of cardiovascular disease and premature death. New methods for early detection of hypertension and its consequences can reduce complications arising from uncontrolled hypertension. Pulse-wave velocity (PWV), a measure of arterial stiffness, has been recognized as a valuable tool in assessing risk for cardiovascular complications, although its use in clinical practice is currently limited. Here we examine whether brachial--ankle PWV (baPWV) and femoral--ankle PWV (faPWV) are elevated in nonhypertensive volunteers, with and without a history of familial hypertension.

METHODS

Volunteers were recruited and questioned as to their medical background and family history. Participants were divided into two groups based on history of familial hypertension and were measured for baPWV and faPWV. Carotid--femoral PWV was computed from these measurements.

RESULTS

A total of 82 healthy nonhypertensive volunteers (mean age 31.4 ± 9.6) were recruited. Among the study cohort, 43.7% had a history of familial hypertension. There were no between-group differences in any other clinical or demographic characteristics. Both baPWV and faPWV were significantly elevated in volunteers with a history of familial hypertension (10.86 ± 1.69 vs. 9.68 ± 1.52 m/s, P < 0.004, and 7.01 ± 1.65 vs. 6.28 ± 1.26 m/s, P < 0.028, respectively).

CONCLUSION

Volunteers with a history of familial hypertension present with elevated baPWV and faPWV. This is suggestive of increased central and peripheral arterial stiffness in susceptible individuals before the onset of hypertension. Routine measurement of these parameters may allow for early intervention and risk stratification, especially in persons with a history of familial hypertension.

The association between pulse wave analysis, carotid-femoral pulse wave velocity and peripheral arterial disease in patients with ischemic heart disease

INTRODUCTION

Functional changes in peripheral arterial disease (PAD) could play a role in higher cardiovascular risk in these patients.

METHODS

123 patients who underwent elective coronary angiography were included. Ankle-brachial index (ABI) was measured and arterial stiffness parameters were derived with applanation tonometry.

RESULTS

6 patients (4.9%) had a previously known PAD (Rutherford grade I). Mean ABI was 1.04 ± 0.12, mean subendocardial viability ratio (SEVR) 166.6 ± 32.7% and mean carotid-femoral pulse wave velocity (cfPWV) 10.3 ± 2.4 m/s. Most of the patients (n = 81, 65.9%) had coronary artery disease (CAD). There was no difference in ABI among different degrees of CAD. Patients with zero- and three-vessel CAD had significantly lower values of SEVR, compared to patients with one- and two-vessel CAD (159.5 ± 32.9%/158.1 ± 31.5% vs 181.0 ± 35.2%/166.8 ± 27.8%; p = 0.048). No significant difference was observed in cfPWV values. Spearman's correlation test showed an important correlation between ABI and SEVR (r = 0.196; p = 0.037) and between ABI and cfPWV (r = - 0.320; p ≤ 0.001). Multiple regression analysis confirmed an association between cfPWV and ABI (β = - 0.210; p = 0.003), cfPWV and mean arterial pressure (β = 0.064; p < 0.001), cfPWV and age (β = 0.113; p < 0.001) and between cfPWV and body mass index (BMI (β = - 0.195; p = 0.028), but not with arterial hypertension, dyslipidemia, diabetes mellitus or smoking status. SEVR was not statistically significantly associated with ABI using the same multiple regression model.

CONCLUSION

Reduced ABI was associated with increased cfPWV, but not with advanced CAD or decreased SEVR.

Tissue optical perfusion pressure: a simplified, more reliable, and faster assessment of pedal microcirculation in peripheral artery disease

Oscillometry is an alternative to continuous-wave Doppler (cw-Doppler) to determine peripheral artery disease (PAD) severity using the ankle-brachial index (ABI). cw-Doppler ABI differentiates systolic pressure of ATP and ADP where either one of both values in most patients is higher (high) and the other value is lower (low). In contrast, oscillometric ABI measures the strongest signal and hence misses the lower value. Both do not take pedal perfusion into consideration. Simultaneous determination of tissue microperfusion cares for pedal PAD. ABI was determined by cw-Doppler and oscillometry. Tissue optical perfusion pressure (TOPP) was taken from the first toe using photoplethysmography. 323 patients were evaluated retrospectively in 3 independent groups. group 1 (99 patients) compared TOPP and oscillometric ABI with systolic cw-Doppler-pressure and cw-Doppler ABI. In group 2 (103 patients) TOPP was compared with toe pressure (TP). In group 3 (121 symptomatic patients) TOPP and ABI at rest and after stress were compared (ultrasound examination and magnetic resonance angiography (MRA) or computer tomography angiography (CTA) as control). Bland-Altman-plot analysis presented no significant difference between oscillometric ABI and the high cw-Doppler ABI (group 1). TOPP showed a difference of 26mmHg to the low cw-Doppler-pressure and none to the high cw-Doppler-pressure. In group 2 TOPP correlates to TP but presented a difference of 37 mmHg. group 3 showed weak or no correlation between ABI and walking distance. Oscillometric ABI correlates significantly to TOPP. To conclude, data after stress present a better correlation than at rest. We conclude that TOPP provides absolute values of pedal macro-/microcirculation at rest and after stress tests.NEW & NOTEWORTHY This new application of photoplethysmography investigated the microcirculation in peripheral artery disease at the level of the toe pad and determined the tissue optical perfusion pressure as the first pulsatile signal during automatic cuff deflation at the ankle. It is the first time that this method has been integrated for simultaneous routine examination in an automatic oscillometric ankle-brachial index (ABI) system. This quick and simple measurement technique provides clinical information on the microcirculation downstream the routine ABI measurement at rest and in particular after stress test.

The reliability of the ankle brachial index: a systematic review

Background

The ankle brachial index (ABI) is widely used in clinical practice as a non-invasive method to detect the presence and severity of peripheral arterial disease (PAD). Current guidelines suggest that it should be used to monitor potential progression of PAD in affected individuals. As such, it is important that the test is reliable when used for repeated measurements, by the same or different health practitioners. This systematic review aims to examine the literature to evaluate the inter- and intra-rater reliability of the ABI.

Methods

A systematic search of MEDLINE, EMBASE and CINAHL Complete was conducted to 20 January 2019. Two authors independently reviewed and selected relevant studies and extracted the data. Methodological quality was determined using the Quality Appraisal of Reliability (QAREL) Checklist.

Results

Fifteen studies of ABI reliability in a range of patient populations were identified as suitable for inclusion in the review: seven considered inter-rater reliability, four intra-rater reliability, and four studies evaluated both inter- and intra-rater reliability. Inter-rater reliability was found to be highly variable, with intraclass correlation coefficients (ICC's) ranging from poor to excellent (ICC 0.42-1.00), while intra-rater also demonstrated considerable variation, with ICCs from 0.42-0.98. Meta-analysis was not possible due to the lack of statistical information reported.

Conclusions

Results of included studies suggest the inter- and intra-tester reliability of the ABI is acceptable. However, inconsistencies in obtaining systolic pressure measurements, calculating ABI values, and incomplete reporting of methodologies and statistical analysis make it difficult to determine the validity of the results of included studies. Further research, with more consistent reliability methodology, statistical analysis and reporting conducted in populations at risk of PAD is needed to conclusively determine the ABI reliability.

Heart failure prevalence in the general population: SOBOTA-HF study rationale and design

Aims

Epidemiological heart failure (HF) data in the era of natriuretic peptides and echocardiography are scarce. The primary aim of this study is to evaluate the HF prevalence in the general population. We will also investigate natriuretic peptide cut‐off for diagnosis of HF. Finally, we will be able to identify left ventricular function phenotypes and study relations between cardiac function, clinical presentation, and health‐related quality of life.

Methods and results

Screening Of adult urBan pOpulation To diAgnose Heart Failure (SOBOTA‐HF) is a cross‐sectional prevalence study in a representative sample of Murska Sobota residents aged 55 years or more. Individuals will be invited to attend screening visit with point‐of‐care N‐terminal pro‐b‐type natriuretic peptide (NT‐proBNP) testing. All subjects with NT‐proBNP ≥ 125 pg/mL will be invited for a diagnostic visit that will include history and physical examination, electrocardiogram, echocardiography, blood and urine sampling, ankle brachial index, pulmonary function tests, body composition measurement, physical performance tests, and questionnaires. To validate the screening procedure, a control group (NT‐proBNP < 125 pg/mL) will undergo the same diagnostic evaluation. An external centre will validate echocardiography results, and the HF diagnosis will be adjudicated within an international HF expert panel. Overall and age‐specific HF prevalence will be calculated in individuals ≥ 55 years and extrapolated to the whole population.

Conclusions

The SOBOTA‐HF study will test the latest HF guideline diagnostic criteria in the general population sample. Next to HF prevalence, it will provide insight into left ventricular function and general patient phenotype; we will also extend current understanding of natriuretic peptides for HF screening.

The importance of accurate methodology in ABPI calculation when assessing lower limb wounds

Recent health economic publications have highlighted the cost of wound care and demonstrated the important role played by community and practice nurses in delivering care. Leg ulcers form a significant proportion of the wounds managed in the community. Data indicates that many patients are managed with no specific diagnosis or without calculation of the ankle brachial pressure index (ABPI), despite care guidelines emphasising the importance of a full assessment including Doppler ABPI calculation in patient management. This article highlights the important role Doppler ABPI plays in patient assessment and describes the methodology, focusing on the importance of correct application of the technique if reliable reproducible results are to be obtained. The rationale for obtaining blood pressure readings from both arms is discussed, and the possible error resulting from reliance on single upper limb blood pressure measurement for both manual and automated ABPI calculation is highlighted and its impact on ABPI calculation illustrated.

Accuracy and repeatability of the Dopplex Ability

BACKGROUND

Ankle-brachial index (ABI) and pulse volume recordings (PVR) are non-invasive tests used in diagnosis of peripheral arterial disease (PAD). The Dopplex Ability is an automated ABI/PVR device utilising air plethysmography, offering easy and rapid PAD diagnosis. The accuracy and repeatability of the Dopplex were assessed in comparison to the Doppler/air plethysmography-based Parks Flo-Lab system.

METHODS

Sixty-six patients (n = 129 lower limbs) were assessed with both Dopplex and Parks systems. For Dopplex ABI and PVR to be deemed accurate, it had to be within ±10% of the Parks ABI, and the PVR grade (1-4) had to be equal. The coefficient of variation (CV) was calculated from three repeat ABI/PVR readings to assess repeatability.

RESULTS

The Dopplex and Parks devices correlated poorly for ABI (R2 = 0.17) with only 43% of ABIs and 69% of PVRs meeting the accuracy criteria compared to the Parks values. The specificity and sensitivity were 56% and 82%, respectively for ABI, and 91% and 89%, respectively for PVRs. The Dopplex showed a significantly higher CV for both ABIs and PVRs compared to the Parks.

CONCLUSION

We found the Dopplex device to demonstrate suboptimal accuracy and repeatability in assessing ABI/PVR, and it was deemed unsuitable for use in our community.

The accuracy of an oscillometric ankle-brachial index in the diagnosis of lower limb peripheral arterial disease: A systematic review and meta-analysis

INTRODUCTION

Peripheral arterial disease (PAD) remains underdiagnosed and undertreated, partly because of limitations in the Doppler ankle-brachial index (ABI), the non-invasive gold standard.

OBJECTIVE

This systematic review and meta-analysis aims to compare the diagnostic accuracy of the oscillometric ABI and the Doppler ABI, and to examine the influence of two approaches to analysis: legs vs subjects and inclusion of oscillometric errors as PAD equivalents vs exclusion.

METHODS

Systematic searches in EMBASE, MEDLINE, Web of Science and the Cochrane Library databases were performed, from inception to February 2017. Random-effects models were computed with the Moses-Littenberg constant. Hierarchical summary receiver operating characteristic curves (HSROC) were used to summarise the overall test performance.

RESULTS

Twenty studies (1263 subjects and 3695 legs) were included in the meta-analysis. The pooled diagnostic odds ratio (dOR) for the oscillometric ABI was 32.49 (95% CI: 19.6-53.8), with 65% sensitivity (95% CI: 57-74) and 96% specificity (95%CI: 93-99). In the subgroup analysis, the "per subjects" group showed a better performance than the "per legs" group (dOR 36.44 vs 29.03). Similarly, an analysis considering oscillometric errors as PAD equivalents improved diagnostic performance (dOR 31.48 vs 28.29). The time needed for the oscillometric ABI was significantly shorter than that required for the Doppler ABI (5.90 vs 10.06 minutes, respectively).

CONCLUSIONS AND RELEVANCE

The oscillometric ABI showed an acceptable diagnostic accuracy and feasibility, potentially making it a useful tool for PAD diagnosis. We recommend considering oscillometric errors as PAD equivalents, and a "per subject" instead of a "per leg" approach, in order to improve sensitivity. Borderline oscillometric ABI values in diabetic population should raise concern of PAD.

Validity and reliability of the ankle-brachial index by oscillometric blood pressure and automated ankle-brachial index

Background:

This study was conducted to assess the validity and reliability of ankle-brachial index (ABI) by oscillometric blood pressure (BP) measurement as compared with an automated ABI as a gold standard.

Materials and Methods:

This study was conducted at Golden Jubilee Medical Center, Thailand. All the data were collected from 303 patients at risk of peripheral arterial disease (PAD) who were 45 years of age or above and who underwent treatment at the outpatient medical clinic between June and December 2015. Patients who were followed up at the medical clinic had both oscillometric BP measurement (Terumo, ES-P600) and an automated ABI (oscillometric method) at the same time. Sensitivity, specificity, positive predictive value, and negative predictive value of the oscillometric BP measurements to predict an abnormal ABI (<0.90) were determined using the automated ABI as the gold standard.

Results:

ABI values were similar between the two methods. The oscillometric BP method for determining an ABI (cutoff point <0.90) on the right side had a sensitivity of 88.89%, specificity of 99.32%, an accuracy of 99.01%, a positive predictive value of 80%, and a negative predictive value of 99.32% whereas ABI on the left side had a sensitivity of 69.23%, a specificity of 99.66%, an accuracy of 98.35%, a positive predictive value of 90%, and a negative predictive value of 98.63%. Reliability of the oscillometric BP method by Kappa statistics was 0.84 on the right side and 0.77 on the left side (P = 0.000).

Conclusion:

The oscillometric BP method is a reliable and useful alternative to conventional automated ABI determination in patients with no severe arterial occlusion for estimation of the prevalence and screening of PAD in primary health-care settings.