Upstroke Time Is a Useful Vascular Marker for Detecting Patients With Coronary Artery Disease Among Subjects With Normal Ankle-Brachial Index

Current topic of vascular function in hypertension in 2023-2024

Noninvasive tests of vascular function are useful for assessing the severity of atherosclerosis and risk of cardiovascular events, understanding the pathophysiology of cardiometabolic disorders, and investigating the effects of therapeutic interventions on cardiovascular morbidity and mortality, all of which can provide additional information for the management of patients with cardiovascular risk factors or a history of cardiovascular disease. In 2023-2024, many excellent articles on vascular function were published in Hypertension Research and other major cardiovascular and hypertension journals, and we summarize the emerging evidence on vascular function in this review. We hope that this review will be helpful for the management of patients with cardiovascular risk factors in clinical practice and for future basic and clinical research on vascular function.

Upstroke time is a more useful marker of atherosclerosis than percentage of mean arterial pressure for detecting coronary artery disease in subjects with a normal ankle-brachial index

Upstroke time (UT) and percentage of mean arterial pressure (%MAP) at the ankle have been shown to serve as atherosclerotic markers. The purpose of this study was to directly compare the diagnostic accuracy of UT with that of %MAP for clinical coronary artery disease (CAD) in subjects with a normal ankle-brachial index (ABI) in both legs. We measured UT and %MAP in 1953 subjects with a normal ABI. The optimal cutoff values of UT and %MAP derived from a receiver operating characteristic (ROC) curve to diagnose CAD were 148 ms and 40.4%, respectively. Multivariable analyses revealed that both UT ≥ 148 ms (odds ratio [OR], 2.72; p < 0.001) and %MAP ≥ 40.4% (OR, 1.28; p = 0.003) were significantly associated with CAD. When the subjects were divided into four groups according to the cutoff values of UT and %MAP, there was no significant difference in the risk of CAD between subjects with UT ≥ 148 ms and %MAP < 40.4% and those with UT ≥ 148 ms and %MAP ≥ 40.4% (OR, 1.45; p = 0.09). ROC curve analyses revealed that the area under the curve value of UT was significantly higher than that of %MAP (0.69 vs. 0.53, p < 0.001). The addition of UT to traditional risk factors significantly improved the diagnostic accuracy for CAD (0.82 to 0.84, p = 0.004), whereas the addition of %MAP to traditional risk factors did not improve the diagnostic accuracy for CAD (0.82 to 0.82, p = 0.84). UT is more useful than %MAP for identifying individuals with CAD among those with a normal ABI.

Percentage of mean arterial pressure as a marker of atherosclerosis for detecting patients with coronary artery disease

The percentage of mean arterial pressure (%MAP) is the height of the mean arterial waveform divided by the peak amplitude of the waveform of pulse volume recording. The purpose of this study was to determine whether the cutoff value of 45% for %MAP at the ankle, which is recommended for the diagnosis of lower extremity artery disease, in combination with ankle-brachial index (ABI) is useful for detecting patients with clinical coronary artery disease (CAD) and investigate the optimal cutoff value of %MAP to diagnose patients with CAD.　We measured ABI and %MAP in 2213 subjects　(mean age: 61.2 ± 15.5 years). Multivariate analysis revealed that %MAP ≥ 45% was significantly associated with a higher risk of CAD after adjusting for traditional cardiovascular risk factors (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.43-3.21; p < 0.001). However, the association was no longer significant after adjusting for ABI (OR, 1.39; 95% CI, 0.83-2.33; p = 0.21), whereas ABI was significantly associated with CAD (OR, 0.98; 95% CI, 0.97-0.99; p = 0.005). The optimal cutoff value of %MAP derived from a receiver operating characteristic curve to diagnose CAD was 40.3%. Multivariate analysis revealed that %MAP ≥ 40.3% was significantly associated with a higher risk of CAD (OR, 1.63; 95% CI, 1.19-2.24; p = 0.002) independent of ABI (OR, 0.98; 95% CI, 0.97-0.99; p = 0.002). The cutoff value of 40.3%, but not 45%, for %MAP may be useful for detecting patients with advanced atherosclerosis and for cardiovascular risk assessment independent of ABI. REGISTRATION INFORMATION: http://www.umin.ac.jp (University Hospital Medical Information Network Clinical Trials Registry) (UMIN000039512).

Update on Hypertension Research in 2021

In 2021, 217 excellent manuscripts were published in Hypertension Research. Editorial teams greatly appreciate the authors' contribution to hypertension research progress. Here, our editorial members have summarized twelve topics from published work and discussed current topics in depth. We hope you enjoy our special feature, "Update on Hypertension Research in 2021".

Falsely normalized ankle-brachial index despite the presence of lower-extremity peripheral artery disease: two case reports

Background

The ankle-brachial index measurement is used for screening and diagnosis of lower-extremity peripheral artery disease and cardiovascular risk assessment. However, the value is occasionally unreliable since the oscillometric ankle-brachial index can be elevated and falsely normalized despite the presence of lower-extremity peripheral artery disease because of the incompressibility of infrapopliteal arteries at the ankle, potentially leading to a missed diagnosis of lower-extremity peripheral artery disease or underestimation of cardiovascular risk.

Case presentation

We report two cases of lower extremity peripheral artery disease with normal ankle-brachial index (a 76-year-old Asian man and a 66-year-old Asian man). In both cases, the ankle-brachial index was within the normal range (1.00–1.40) despite the presence of lower-extremity peripheral artery disease, whereas upstroke time at the ankle calculated from the pulse volume waveform simultaneously obtained by plethysmography during the ankle-brachial index measurement was prolonged (≥ 180 milliseconds). Diagnostic imaging tests revealed the presence of occlusive arterial disease in the lower extremity and severe calcification of infrapopliteal arteries.

Conclusions

In both cases, the oscillometric ankle-brachial index might have been falsely normalized despite the presence of lower-extremity peripheral artery disease because of calcified incompressible infrapopliteal arteries. Sole reliance on the ankle-brachial index value may lead to a missed diagnosis of lower-extremity peripheral artery disease or underestimation of cardiovascular risk. Upstroke time at the ankle was helpful for suspecting the presence of lower-extremity peripheral artery disease in both patients with normal ankle-brachial index. In addition to history-taking and vascular examination, upstroke time at the ankle should be carefully checked for accurate diagnosis of peripheral artery disease and cardiovascular risk assessment in patients with normal ankle-brachial index.

Retinal Blood Velocity Waveform Characteristics With Aging and Arterial Stiffening in Hypertensive and Normotensive Subjects

Purpose

We aimed to explore the velocity waveform characteristics of the retinal artery associated with age and the cardio-ankle vascular index (CAVI) as a conventional arterial stiffness marker by applying the Doppler optical coherence tomography (DOCT) flowmeter.

Methods

In this cross-sectional study, DOCT flowmeter imaging was performed in 66 participants aged 21 to 83 years (17 men, 49 women) with no history of eye diseases and no systemic diseases, except for hypertension. Retinal blood velocity waveform was analyzed where several parameters in time (upstroke time, T1, T2, T3, and T4) and area under the waveform (area elevation, area declination, A1, A2, A3, and A4) were extracted. Systolic blood pressure–adjusted Pearson's coefficients were calculated to determine the correlations of each parameter with age or CAVI.

Results

Corrected upstroke time (UTc) was the waveform parameter most positively correlated with age (r = 0.497, P < 0.001). Area declination was the waveform parameter most negatively correlated with age (r = −0.682, P < 0.001) and CAVI (r = −0.601, P < 0.001).

Conclusions

We extracted the waveform parameters associated with the risks of arterial stiffening. The velocity waveform analysis of the retinal artery with DOCT flowmeter potentially could become a new method for arterial stiffness identification.

Translational Relevance

DOCT flowmeter could evaluate arterial stiffening in a different way from the conventional method of measuring arterial stiffening using pressure waveform. Because the DOCT flowmeter can easily, quickly, and noninvasively provide a retinal blood velocity waveform, this system could be useful as a routine medical examination for arterial stiffening.

Upstroke time as a marker of atherosclerosis in patients with diabetes mellitus who have a normal ankle-brachial index

We measured upstroke time in 509 patients with diabetes who had a normal ankle-brachial index (ABI) (1.00 ≤ ABI ≤ 1.40) (443 men and 66 women; mean age: 67.6 ± 10.8 years). The prevalence of cardiovascular disease was significantly higher in patients with prolonged upstroke time at the ankle than in patients with normal upstroke time. The association between prolonged upstroke time and a higher risk of cardiovascular disease remained significant after adjusting for confounders.

Ankle-brachial index: more than a diagnostic test?

The ankle-brachial index (ABI) is the relationship between the systolic blood pressure taken at the ankle level and the brachial artery. A pathological ABI (<0.90 or >1.40) indicates the presence of peripheral artery disease (PAD). Many studies indicate the great utility of this test in the diagnosis of PAD due to its ease of use, reproducibility, low cost, and high cost-effectiveness. This evaluation can be directly correlated with cardiovascular morbidity and mortality; however, it has recently been confirmed that a low ABI can be a predictor of major cardiovascular events, as it is related to diabetes mellitus, chronic coronary disease, stroke, and more. The objective of this work was to review the current evidence on the importance of ABI in the diagnosis of PAD and its main role as a predictor of cardiovascular morbidity and mortality.

Effect of BMI on Central Arterial Reflected Wave Augmentation Index, Toe-Brachial Index, Brachial-Ankle Pulse Wave Velocity and Ankle-Brachial Index in Chinese Elderly Hypertensive Patients with Hemorrhagic Stroke

BACKGROUND

Hypertensive cerebral hemorrhage seriously endangers the health of the elderly. However, the relationship between obesity and arterial elasticity in hypertensive cerebral hemorrhage remains to be clarified. The purpose of our study is to explore the associations between body mass index (BMI) and central arterial reflected wave augmentation index (cAIx), toe-brachial index (TBI), brachial-ankle pulse wave velocity (baPWV), and ankle-brachial index (ABI) in the elderly hypertensive patients with hemorrhagic stroke.

MATERIALS AND METHODS

A total of 502 elderly hypertensive patients with hemorrhagic stroke and 100 healthy controls were collected. According to the BMI, patients were divided into normal BMI, overweight, obesity, and obese groups. The multivariate logistic regression model was used to establish a risk model for elderly hypertensive hemorrhagic stroke.

RESULTS

Compared with the normal BMI group, systolic blood pressure (SBP), diastolic blood pressure (DBP), cAIx, and baPWV in the abnormal BMI group were significantly increased (P < 0.05), while TBI and ABI were significantly decreased (P < 0.05). Logistic regression showed that BMI (OR = 1.031, 95%CI: 1.009-1.262), cAIx (OR = 1.214, 95%CI: 1.105-1.964), TBI (OR = 0.913, 95%CI: 0.885-0.967), baPWV (OR = 1.344, 95%CI: 1.142-2.147), and ABI (OR = 0.896, 95%CI: 0.811-0.989) are important factors for the occurrence of hemorrhagic stroke in the elderly hypertensive patients. ROC curve analysis showed that the AUC of cAIx, TBI, baPWV, ABI, and BMI were 0.914, 0.797, 0.934, 0.833, and 0.608, respectively. The final prediction model of hemorrhagic stroke elderly hypertensive patients was Y_(P)= 65.424 + 0.307(cAIx) - 13.831(TBI) + 0.012(baPWV) - 0.110(ABI) + 0.339(BMI).

CONCLUSIONS

Obesity is associated with decreased arterial elasticity. Therefore, reasonable weight management of the elderly may be of great significance for reducing the risk of hemorrhagic stroke in patients with hypertension.

Upstroke Time Is a Useful Vascular Marker for Detecting Patients With Coronary Artery Disease Among Subjects With Normal Ankle-Brachial Index

Background Upstroke time is the transit time from the nadir to peak of the waveform of pulse volume recording. The purpose of this study was to determine whether upstroke time at the ankle is a useful vascular marker for detecting patients with advanced atherosclerosis in combination with ankle-brachial index (ABI). Methods and Results We measured upstroke time and ABI in 2313 subjects (mean age, 61.2±15.3 years). The prevalence of coronary artery disease (CAD) was significantly higher in patients with prolonged upstroke time (≥180 ms) than in subjects with normal upstroke time (<180 ms) (29.6% versus 11.8%; P<0.001), with a significant association between prolonged upstroke time and an increased risk of CAD (odds ratio [OR], 1.61; 95% CI, 1.07-2.44; P=0.02). In 1954 subjects with normal ABI (1.00 ≤ ABI ≤ 1.40), the prevalence of CAD was significantly higher in patients with prolonged upstroke time than in subjects with normal upstroke time (29.5% versus 10.6%; P<0.001), with a significant association between prolonged upstroke time and CAD (OR, 2.33; 95% CI, 1.41-3.87; P=0.001), whereas there was no significant association between upstroke time and CAD in subjects with low ABI (<1.00) (OR, 1.24; 95% CI, 0.72-2.16; P=0.44). Conclusions Upstroke time may be a useful vascular marker for detecting patients with CAD, especially in subjects with normal ABI who are usually considered not to have advanced atherosclerosis by ABI measurement alone. More attention should be paid to upstroke time for detecting patients with advanced atherosclerosis. Registration URL: https://www.umin.ac.jp; Unique identifier: UMIN000039512.