Association of Arterial Velocity Pulse Index and Arterial Pressure–Volume Index with Central Arterial Stiffness and Cardiac Function in the Japanese Population

Background: The Arterial Velocity Pulse Index (AVI) and Arterial Pressure–Volume Index (API) are novel non-invasive indices of arterial stiffness derived from cuff-oscillometric measurements. Previous studies have shown that elevated AVI and API are associated with the severity of coronary artery disease and the ability to predict future cardiovascular events. However, the hemodynamic and echocardiographic characteristics of patients with concomitantly high AVI and API remain unclear. Methods: We retrospectively analyzed 112 consecutive cardiovascular outpatients (mean age 69.1 ± 12.2 years, 64.3% male) seen between January and April 2019 at Yokohama City University Hospital. The AVI and API were measured using a multifunctional sphygmomanometer (PASESA AVE1500, Shisei Datum, Japan) and averaged over a maximum of three measurements. Patients were classified into four groups according to previously established cutoff values (AVI ≥ 27, API ≥ 32). Central arterial pulse wave parameters were assessed using SphygmoCor XCEL (AtCor Medical, Sydney, Australia), and echocardiographic parameters were obtained according to standard protocols. Intergroup differences were analyzed using the Kruskal–Wallis test with Steel–Dwass post hoc comparisons. Results: Compared with the low-risk group (low AVI/low API), the high-risk group (high AVI/high API) had significantly higher brachial systolic BP (139.2 132.8–149 vs. 128 120–136.7 mmHg, p = 0.0011), central systolic BP (127.5 122.3–139 vs. 117.7 110.3–123.7 mmHg, p = 0.0018), and central pulse pressure (56.2 51.4–60.3 vs. 37.7 32–43 mmHg, p < 0.001). The forward and reflected wave amplitudes were significantly greater, with prolonged ejection duration and aortic T2 time. The Buckberg subendocardial viability ratio was significantly lower in the high-risk group (129.5 119.7–145.2 vs. 148.3 130–168.3, p = 0.040). Echocardiography revealed reduced e′ velocity (5 4.1–5.8 vs. 6.7 5.2–8 cm/s, p = 0.035) and increased E/e′ (13.2 11.1–15.1 vs. 9.7 7.9–11.3, p = 0.026) in the high-risk group, suggesting the presence of impaired diastolic function without reduced LVEF. Conclusions: Patients with high AVI and API exhibited greater central and peripheral arterial stiffness, higher systolic and pulse pressures, and impaired diastolic function compared with those with low values. These findings support the use of a cardiovascular pathophysiological model in which elevated AVI/API identify individuals at increased risk of progression to heart failure and ischemic heart disease.