Specificity Of Ankle-brachial Index Research Articles

Diagnostic accuracy of ankle-brachial index measurement in peripheral Arterial disease in TurkishAdults: A comparison with angiography

Objective: This study aims to assess the sensitivity and specificity of ankle-brachial index (ABI) measurements in diagnosing peripheral artery disease (PAD) among a cohort of Turkish subjects, with angiography serving as the reference standard. Material and Methods: In this single-center, cross-sectional and observational study, subjects who had an aorta and lower extremity arterial imaging by angiography subsequently underwent an ABI measurement. Anthropometric measurements, cardiovascular risk factors, and blood biochemistry data were recorded. Sensitivity and specificity analyses were performed for a low ankle-brachial index (ABI ≤ 0.9), with angiography as the reference standard. Results: A total of 57 patients (age: 59.1±15.9, male/female: 47/10) were included. Diabetes mellitus, coronary artery disease and cerebrovascular disease were present in 40.4%, 42.1% and 15.8% of the participants, respectively. Three or more cardiovascular risk factors were present in 54.4%. The angiographic diagnostic method was computed tomography angiography in 57.9%, digital subtraction angiography in 38.6%, and magnetic resonance angiography in 3.5% of the subjects. The presence of PAD on angiography was documented in 55 of 57 participants. The calculated mean ABI value was 0.6±0.2 in the overall group, and a low ABI (≤0.9) was found by 82.5% (n = 47). Compared to angiography, the low ankle-brachial index (ABI) test demonstrated a sensitivity of 83.6% and a specificity of 50%. The positive predictive value of 97.9% was calculated. When an ABI≤0.95 was used as the diagnostic threshold, the sensitivity of the ABI test increased to 90.9%. Conclusion: Our study confirms the reliability of ABI measurements as a diagnostic method for lower extremity peripheral artery disease (PAD) when compared to angiographic techniques, the gold standard. Establishing a higher cut-off value (≤0.95) may enhance the diagnostic performance of the test in Turkish patients.

Pengukuran Penyakit Arteri Koroner Dengan Menggunakan Ankle-Brachial Index (ABI)

Background: Coronary artery disease (CAD) is the main cause of death in the world. In this study we assessed the ankle-brachial index (ABI) as a screening tool for CAD. Methods: Between 2020 and 2023, a large population-based cross-sectional study was conducted on 4,207 new patients referred to Harapan Kita Hospital. The patients underwent selective coronary angiography via a radial artery approach. ABI was calculated for all patients. Researchers compared ABI with coronary angiography results to determine the specificity and sensitivity of ABI as a screening tool. Results: Abnormal ABI was significantly more common in patients with proven severe CAD (893, 54.8%) than in patients with proven mild CAD (33, 4.7%) or no CAD (94, 5.3% ). The specificity of the ABI was 95.3% and the sensitivity was 54.8%. ABI is associated with risk factors such as smoking, male gender, hypertension, diabetes mellitus and dyslipidemia. Conclusion: ABI can be used as a screening test to prevent CAD with a specificity of 95.3%. We need to consider risk factors other than ABI to improve screening sensitivity. Multidimensional scoring systems should consider risk factors and other noninvasive tests in addition to ABI to develop an ideal screening system for CAD

Sensitivity and Specificity of Ankle Brachial Index (ABI) and Pulse Wave Handheld Doppler (PWHD) Compared with Angiography as Diagnostic Test for Patients with Peripheral Artery Disease (PAD)

Background: Peripheral artery disease (PAD) is a clinical condition that occurs due to atherosclerosis and narrowing of the arteries involving the aorta, branches of the visceral arteries such as the iliac arteries, and the arteries of the distal extremities. The femoropopliteal artery is the most commonly involved site in patients with atherosclerotic PAD. Ankle Brachial Index (ABI) determination may have limited value in some patients with diabetes, because calcification of the tibial artery can render it uncompressible, resulting in a very high ABI value (>1.40). Handheld vascular Doppler with pulse volume waveform interpretation (PVW) is an easily available and non-invasive modality for evaluation of the inferior extremity arteries and can detect the severity of blood flow disturbances or ongoing PAD. The best diagnostic method for PAD is angiography using digital substraction angiography (DSA) to assess existing atherosclerotic lesions. The advantages of ABI and PWHD examinations are in terms of simplicity, ease of use, and non-invasiveness instead of angiography in PAD diagnosis led the investigators to compare the sensitivity and specificity values between ABI and PWHD with angiography as a diagnostic test for PAD patients. Methods: This study used a cross-sectional diagnostic test design with the subjects were patients diagnosed with PAD, both outpatients and inpatients at Prof. DR. R.D Kandou Manado. ABI, PWHD and angiography examination were performed on all study subjects. Results: The data show that ABI has a sensitivity of 95.2% and a specificity of 80% in diagnosing PAD patients when compared to angiography as the standard of diagnosis of PAD. PWHD compared to angiography has a sensitivity of 100% and a specificity of 100%. When ABI and PWHD are combined, it has a sensitivity of 100% with a specificity of 80%. The sensitivity and specificity of PWHD compared to angiography based on angiographic location in popliteal artery has a sensitivity of 91.7% and a specificity of 92.6%. PWHD compared with angiography on posterior tibial artery (PTA) has a sensitivity of 81% and a specificity of 88.9%. ABI compared with angiography on dorsalis pedis artery has a sensitivity of 100% and a specificity of 71.4%, with p <0.0001. Conclusion: The high sensitivity and specificity of ABI and PWHD can be used as a diagnostic test tool for PAD patients by general practitioners in first level health facilities.

To Study the Sensitivity and Specificity of Ankle Brachial Index in Diagnosis of Peripheral Arterial Disease in Diabetics With Coronary Artery Disease at a Large Tertiary Care Teaching Hospital

The aim of study was to determine the sensitivity and specificity of ankle brachial index in diagnosis of peripheral arterial disease in diabetics with coronary artery disease at a teaching hospital in North India. Materials and methods: All diabetic patients admitted with coronary artery disease who undergo coronary angiography irrespective of their presentation (stable angina, unstable angina, NSTEMI, STEMI) were included in the study. Systolic blood pressures of both arms at the brachial arteries and both lower limbs at the dorsalis pedis arteries were taken with the help of sphygmomanometer and a hand held doppler probe and recorded in the proforma. The higher of the two systolic pressures recorded at the ankle was divided by the highest of the systolic pressures recorded in the arms to get the ankle brachial index. The results of ABI were compared with peripheral angiography.

Application of whole-brain CT perfusion combined with ankle-brachial index in acute cerebral ischemia

Objective To investigate the clinical value of whole-brain CT perfusion combined with ankle-brachial index(ABI)in patients with acute cerebral ischemia.Methods A total of 105patients who were suspected of having cerebral ischemia were selected in this study,including 33patients in the abnormal ABI group and 72patients in normal ABI group. Examination by a 320-detector row whole-brain computed tomography(CT)scan with CT angiography(CTA)and CT perfusion was given to all the patients with stable symptoms.The perfusion parameters,including cerebral blood flow(CBF), cerebral blood volume(CBV),mean transit time(MTT),time to peak(TTP)and delay time,were obtained.The brain perfusion images were evaluated by two experienced physicians,and then the positive predictive value,negative predictive value,sensitivity and specificity of ABI in predicting brain CT perfusion abnormalities were calculated.Results Sixty-eight patients showed brain CT perfusion abnormalities,manifested as prolonged MTT and TTP,increased,normal or reduced CBV, and normal or reduced CBF.The 68patients included 25with abnormal ABI and 43with normal ABI.The rate of positive CT perfusion in the abnormal ABI group(75.8%,25/33)was significantly higher than that in the normal ABI group(59.7%,43/72; P=0.039);the relative MTT and the relative TTP in the abnormal ABI group were also significantly longer than those in the normal ABI group(P0.05).The positive predictive value,negative predictive value,sensitivity,and specificity of ABI predicted brain CT perfusion abnormalities were 75.8%,40.3%,36.8%,and 78.4%,respectively.Conclusion Whole-brain CT perfusion can accurately evaluate the hemodynamic changes at an early stage;simple ABI examination has certain predictive value for brain perfusion abnormalities;and the combination of them may facilitate the earlier detection and treatment of cerebral ischemia.

Measurement of blood pressure, ankle blood pressure and calculation of ankle brachial index in general practice

Low ankle brachial index (ABI) is a sensitive measure of 'burden' of atherosclerosis, indicating cardiovascular risk of the asymptomatic patient. Conventionally, ABI values <0.90 are considered pathological, indicating peripheral arterial disease. The purpose of this study was to establish whether GPs after a short training course can reliably determine ABI compared to assessment in a specialized hospital department. Epidemiological observational study. A total of 6 GPs and 12 general practice nurses from six practices were recruited for the study. Doppler measurements and ABI calculations were performed according to guidelines used by the Department of Nuclear Medicine, Odense University Hospital. On average, blood pressure measurements in general practice yielded lower values than those measured at the hospital. Differences in brachial and ankle blood pressure were -7 mmHg (-43 to 30 mmHg) and -14 mmHg (-63 to 33 mmHg), respectively. Sensitivity and specificity of ABI in general practice were 1.00 (0.87-1.00) and 0.79 (0.69-0.88), respectively. Predictive value of ABI measured <0.9 in general practice was 0.62 (0.46-0.76). Findings in general practice and at the Department of Nuclear Medicine were concordant with regard to the threshold value of ABI 0.9. However, this study does not warrant a recommendation of doppler measurements or assessment of ABI as screening or diagnostic procedure due to low specificity of assessments in general practice. Our results indicate a high number of false-positive tests if the method is applied for screening in general practice.

Combination of ankle-brachial index and coronary artery calcium score as a predictor for 3-vessel coronary artery disease in older patients

ObjectiveTo get the sensitivity, specificity and accuracy of ankle-brachial index (ABI) and coronary artery calcium score (CACS) to judge the 3-vessel coronary artery lesions. Furthermore, to investigate whether the value...

Sensitivity and specificity of the ankle—brachial index to diagnose peripheral artery disease: a structured review

The ankle-brachial index (ABI) is a simple, inexpensive diagnostic test for peripheral artery disease (PAD). However, it has shown variable accuracy for identification of significant stenosis. The authors performed a structured review of the sensitivity and specificity of ABI ≤ 0.90 for the diagnosis of PAD. MEDLINE, EMBASE, Cochrane databases, Science Citation Index database, and Biological Abstracts database were searched for studies of the sensitivity and specificity of using ABI ≤ 0.90 for the diagnosis of PAD. Eight studies comprising 2043 patients (or limbs) met the inclusion criteria. The result indicated that, although strict inclusion criteria on studies were formulated, different reference standards were found in these studies, and methods of ABI determination and characteristics of populations varied greatly. A high level of specificity (83.3-99.0%) and accuracy (72.1-89.2%) was reported for an ABI ≤ 0.90 in detecting ≥ 50% stenosis, but there were different levels of sensitivity (15-79%). Sensitivity was low, especially in elderly individuals and patients with diabetes. In conclusion, the test of ABI ≤ 0.90 can be a simple and useful tool to identify PAD with serious stenosis, and may be substituted for other non-invasive tests in clinical practice.

Factors Affecting the Validity of Ankle-Brachial Index in the Diagnosis of Peripheral Arterial Obstructive Disease

We evaluated 158 legs from 79 consecutive patients who had undergone both ankle-brachial index (ABI) measurements and angiography for claudication symptoms between January 2007 and December 2008. The diagnosis of peripheral arterial disease (PAD) in the individual legs was established by angiography. Ankle-brachial index was considered abnormal if it was <0.9. The sensitivity and specificity of ABI was 61% and 87%, respectively. To assess the factors affecting the validity of ABI in the diagnosis of PAD, multivariate logistic regression analysis was conducted. The odds ratios (ORs) for the false negative result of ABI were 4.36 (95% confidence interval [CI] 1.36-13.92) in patients with diabetes mellitus (DM), 3.41 (95% CI 1.10-10.48) in patients with distal lesions, 3.02 (95% CI 1.07-8.49) in elderly patients, and 1.13 (95% CI 0.34-3.42) in patients with mild stenosis. Although ABI is the method of choice for the primary diagnosis of PAD, other supplementary investigations should be considered when there is clinical suspicion of PAD but an ABI <0.9.

Duplex ultrasound of the superficial femoral artery is a better screening tool than ankle-brachial index to identify at risk patients with lower extremity atherosclerosis

The purpose of vascular disease screening is early identification of atherosclerotic disease and the aim of an ankle-brachial index (ABI) is to identify lower extremity (LE) atherosclerosis as a marker for coronary artery disease (CAD). However, early evidence of atherosclerosis may be present in the superficial femoral artery (SFA) with a normal resting ABI. This study was performed to determine if SFA duplex ultrasound (DUS) could detect more patients with LE atherosclerosis than an ABI; be performed in the same or less time as the ABI measurement; and be associated with similar vascular disease markers as the ABI. From January through November 2006, 585 patients were screened for peripheral arterial disease. SFA DUS was included in this Institutional Review Board approved program and demographic/ultrasound data were collected prospectively. SFA DUS findings were divided into six categories. Plaque w/o color change or worse and ABI <0.90 or >1.20 were considered to be abnormal. Data were evaluated using decision matrix and logistical regression analysis. Sensitivity and specificity of SFA DUS using the ABI as the benchmark was 100% and 88%, respectively. Sensitivity and specificity of ABI was 17% and 100%, respectively, using DUS as the standard. DUS detected atherosclerotic disease in 143 SFAs (93 patients) in which the ipsilateral ABI was normal, and there were no false negative SFA DUS studies. Multivariate logistic regression analysis demonstrated the following variables to be significantly and independently associated with an abnormal SFA DUS as well as an abnormal ABI: history of claudication, history of myocardial infarction, and an abnormal carotid DUS. Additional variables (current or past smoker and age >55) were also independently associated with an abnormal SFA DUS but not with an abnormal ABI. Mean time to complete bilateral testing was essentially the same for both tests. SFA DUS is an accurate screening tool and can be utilized in screening protocols in place of the time-honored ABI without prolonging the examination. Traditional vascular disease markers that are found in patients with an abnormal ABI are also associated with an abnormal SFA DUS. SFA DUS identifies more patients with early LE atherosclerosis than does ABI without missing significant popliteal/tibial artery occlusive disease. Finally, an abnormal SFA DUS can be used as an indirect marker to identify more potentially at risk patients with CAD.

Índice tobillo-brazo en la detección de arteriopatía periférica: estudio de validez y concordancia entre Doppler y método oscilométrico

To evaluate the sensitivity and specificity of ankle-brachial index (ABI) determined by oscillometry, using a Doppler ultrasound probe as a gold standard. We also aimed to evaluate the agreement between both methods. Right and left ABI measurements (ABIr,ABIl) with oscillometric (OMRON-705-CP) and Doppler (DIADOP-50) devices in hypertensive patients without peripheral arterial disease. One hundred patients, 61 women, 66.4 (SD 10.9) year-old, smokers 16%, diabetics 38%. Oscillometric and doppler ABI could be calculated in 83% and 93% of patients, respectively. Oscillometric ABIr and ABIl measurements were <0.9 in 9.6% (CI 95%, 4.2-18.1) and 8.4% (CI 95%, 3.4-16.6), respectively, and Doppler measurements were 10.8% (CI 95%, 5.3-18.9) and 15.4% (CI 95%, 8.7-24.5) respectively. The oscillometric ABIr and ABIl sensitivity was 37.5% (CI 95%, 13.7-69.4) and 20.0% (CI 95%, 5.7-51.0) respectively, and the specificity was 93.0% (CI 95%, 84.6-97.8) and 97.1% (CI 95%, 89.9-99.2), respectively. The intraclass correlation (index Doppler/oscillometric device) was 0.64 (CI 95%, 0.44-0.77) for ABIr and 0.62 (CI 95%, 0.41-0.76) for ABIl. About 8.4-15.4% of hypertensive patients attended have an abnormal Doppler ABI measurement. There is not a good concordance between Doppler and oscillometric ABI measurements. This oscillometric device does not seem useful as an ABI screening method.

Pulsatility index is better than ankle-brachial Doppler index for non-invasive detection of critical limb ischaemia in diabetes

Diabetic polyneuropathy of the feet and legs obscures the diagnosis of critical limb ischaemia (CLI) because of lack of pain sensation. Hence, the Fontaine classification does not apply to these patients. Furthermore, many of them will exhibit medial arterial calcification, which invalidates the application of sphygmomanometry. This study was done to evaluate the pulsatility index (P1) assessed at the ankle arteries by colour Doppler ultrasonography as a non-invasive method to diagnose CLI in diabetic polyneuropathy. 140 legs of 106 diabetic patients were studied who presented with polyneuropathy and painlessness of the feet; of these, 117 feet displayed an ulcer or gangrene. CLI was defined as the need for arterial revascularisation, as indicated by the physicians in charge on the basis of a) a foot lesion Wagner grade 1-5, and b) a positive arteriography. All patients were subjected to 4 vascular assessment techniques: digital subtraction arteriography, ankle-brachial Doppler index, systolic ankle blood pressure, and PI. Of the 140 legs, 61 (44%) were affected by CLI, and 76 (54%) by medial arterial calcification. A PI < 1.2 indicated CLI with a sensitivity of 0.87 and a specificity of 0.62. The sensitivity and specificity of ankle-brachial index < 0.9, and of systolic ankle pressure < 70 mm Hg to predict CLI was 0.71 and 0.42, and 0.30 and 0.89, respectively. The pulsatility index is a better noninvasive technique than the ankle-brachial Doppler index or the systolic ankle pressure to assess critical limb ischaemia in diabetic polyneuropathy. A pulsatility index < 1.2 at the ankle arteries is a reliable criterion for diagnosis of CLI in diabetic patients with polyneuropathy.