Carotid-Femoral, Oscillometric and Estimated Pulse Wave Velocity

Hypertension is one of the leading causes of cardiovascular morbidity and mortality worldwide and is strongly associated with myocardial infarction, stroke, heart failure, and premature death. In addition to elevated blood pressure levels, vascular alterations such as arterial stiffness have emerged as important markers of cardiovascular risk. Carotid-femoral pulse wave velocity (cfPWV) is currently considered the gold standard non-invasive method for the assessment of aortic stiffness and has consistently demonstrated independent associations with cardiovascular events and mortality.

Over recent decades, alternative methods for pulse wave velocity (PWV) assessment have been developed. Oscillometric brachial cuff-based devices can estimate PWV through proprietary algorithms derived from blood pressure waveform analysis. The Mobil-O-Graph system is one of the most widely studied oscillometric devices and has shown associations between brachial PWV (brPWV) and cardiovascular outcomes in different clinical settings.

In parallel, estimated pulse wave velocity (ePWV), calculated using mathematical equations based on age and mean blood pressure, has emerged as a simple surrogate marker of arterial stiffness. Previous studies demonstrated that ePWV predicts cardiovascular events and mortality independently of traditional cardiovascular risk scores and even independently of measured cfPWV in some populations.

Although both oscillometric PWV and equation-derived PWV have shown prognostic value, uncertainties remain regarding the degree to which these methods reflect true aortic stiffness when compared with directly measured carotid-femoral PWV. Since oscillometric algorithms and ePWV equations are strongly influenced by age and blood pressure, further studies are necessary to better understand their relationship with the reference standard method.

The present study aims to evaluate the agreement and association between carotid-femoral pulse wave velocity, oscillometric brachial pulse wave velocity, and estimated pulse wave velocity in adults undergoing ambulatory blood pressure monitoring as part of routine clinical evaluation.

This is an observational cross-sectional study conducted in a specialized cardiovascular center in Brazil. The study population includes adults referred for ambulatory blood pressure monitoring (ABPM) for investigation or characterization of blood pressure abnormalities.

Participants undergo office blood pressure measurement, anthropometric assessment, 24-hour ABPM, carotid-femoral pulse wave velocity evaluation, and oscillometric brachial pulse wave analysis under standardized conditions.

Arterial stiffness is assessed using the Complior Analyze device according to current recommendations for non-invasive evaluation of aortic stiffness. Ambulatory blood pressure monitoring and oscillometric brachial PWV measurements are performed using a validated oscillometric device programmed for daytime and nighttime recordings according to guideline recommendations.

Estimated pulse wave velocity is calculated using validated equations derived from the Reference Values for Arterial Stiffness Collaboration based on age and mean blood pressure values.

All participants also underwent routine laboratory evaluation requested by the attending physician at the time of referral for ambulatory blood pressure monitoring. Blood samples collected under fasting conditions included measurements of total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides. Laboratory data obtained from routine clinical care were collected and analyzed for research purposes as part of the present observational study.

The primary objective of the study is to evaluate the agreement between cfPWV, brPWV, and ePWV. Statistical analyses include correlation and agreement analyses between pulse wave velocity methods using standardized statistical approaches.

The study is observational and non-interventional. All procedures are performed within the context of routine clinical care, and all participants provided written informed consent prior to inclusion in the study.

Inclusion criteria

• Individuals older than 18 with an elevated office blood pressure :

• suspected hypertension diagnosis or
• uncontrolled hypertension under treatment

Exclusion criteria

24-hour ABPM recordings presenting:

• less than 70% of the expected measurements or
• fewer than 20 valid awake or seven valid sleeping measurements or
• fewer than two valid daytime and one valid night-time measurement per hour