Cardio-Ankle Vascular Index Reflects Impaired Exercise Capacity and Predicts Adverse Prognosis in Patients With Heart Failure

Prognostic Value of Cardio-Ankle Vascular Index for Cardiovascular and Kidney Outcomes: Systematic Review and Meta-Analysis

Background

Arterial stiffness causes cardiovascular disease and target-organ damage. Carotid-femoral pulse wave velocity is regarded as a standard arterial stiffness metric. However, the prognostic value of cardio-ankle vascular index (CAVI), which is mathematically corrected for blood pressure, remains understudied.

Objectives

The purpose of this study was to determine the association of CAVI with cardiovascular and kidney outcomes.

Methods

PubMed, Scopus, and Web of Science were searched until May 6, 2023, for longitudinal studies reporting the association of CAVI with mortality, cardiovascular events (CVEs) (including death, acute coronary syndromes, stroke, coronary revascularization, heart failure hospitalization), and kidney function decline (incidence/progression of chronic kidney disease, glomerular filtration rate decline). Random-effects meta-analysis was performed. Studies were assessed with the "Quality in Prognostic Studies" tool.

Results

Systematic review identified 32 studies (105,845 participants; follow-up range: 12-148 months). Variable cutoffs were reported for CAVI. The risk of CVEs was higher for high vs normal CAVI (HR: 1.46 [95% CI: 1.22-1.75]; P < 0.001; I2 = 41%), and per SD/unit CAVI increase (HR: 1.30 [95% CI: 1.20-1.41]; P < 0.001; I2 = 0%). Among studies including participants without baseline cardiovascular disease (primary prevention), higher CAVI was associated with first-time CVEs (high vs normal: HR: 1.60 [95% CI: 1.15-2.21]; P = 0.005; I2 = 65%; HR per SD/unit increase: 1.28 [95% CI: 1.12-1.47]; P < 0.001; I2 = 18%). There was no association between CAVI and mortality (HR = 1.31 [0.92-1.87]; P = 0.130; I2 = 53%). CAVI was associated with kidney function decline (high vs normal: HR = 1.30 [1.18-1.43]; P < 0.001; I2 = 38%; HR per SD/unit increase: 1.12 [95% CI: 1.07-1.18]; P < 0.001; I2 = 0%).

Conclusions

Higher CAVI is associated with incident CVEs, and this association is present in the primary prevention setting. Elevated CAVI is associated with kidney function decline.

Aortic Stiffness: A Major Risk Factor for Multimorbidity in the Elderly

Multimorbidity, the coexistence of multiple health conditions in an individual, has emerged as one of the greatest challenges facing health services, and this crisis is partly driven by the aging population. Aging is associated with increased aortic stiffness (AoStiff), which in turn is linked with several morbidities frequently affecting and having disastrous consequences for the elderly. These include hypertension, ischemic heart disease, heart failure, atrial fibrillation, chronic kidney disease, anemia, ischemic stroke, and dementia. Two or more of these disorders (multimorbidity) often coexist in the same elderly patient and the specific multimorbidity pattern depends on several factors including sex, ethnicity, common morbidity routes, morbidity interactions, and genomics. Regular exercise, salt restriction, statins in patients at high atherosclerotic risk, and stringent blood pressure control are interventions that delay progression of AoStiff and most likely decrease multimorbidity in the elderly.

Comparison of Predictive Ability of Arterial Stiffness Parameters Including Cardio-Ankle Vascular Index, Pulse Wave Velocity and Cardio-Ankle Vascular Index0

Cardio-ankle vascular index (CAVI) was developed to reflect the stiffness of the arterial tree from the aortic origin to the ankle. This arterial stiffness parameter is useful for assessing the severity of cardiovascular disease (CVD) and its risk. However, compared to pulse wave velocity (PWV), the conventional gold standard of arterial stiffness parameter, there has been a concern regarding CAVI that there are fewer longitudinal studies for CVD. Furthermore, the accuracy of CAVI for atherosclerotic diseases compared to other parameters has not been well validated. This review article aims to summarize recent findings to clarify the predictive ability of CAVI in longitudinal studies. First, several large longitudinal studies have found that not only baseline CAVI but also CAVI changes during the observation period predict cardiovascular events. Second, CAVI may have superior discriminatory power for all-cause mortality and major adverse cardiovascular endpoints compared to PWV. Furthermore, one large longitudinal study found CAVI to be a stronger predictor for renal function decline compared to PWV as well as CAVI₀, a variant of CAVI that mathematically excludes BP dependence. Additionally, CAVI shows the properties that allow the elucidation of specific hemodynamics in aortic valve disease or hypovolemia. In conclusion, CAVI may be a modifiable arterial stiffness parameter not only for predicting and preventing atherosclerotic diseases but also for elucidating specific hemodynamic pathophysiology.

Intermittent Hypoxic-Hyperoxic Exposures Effects in Patients with Metabolic Syndrome: Correction of Cardiovascular and Metabolic Profile

The aim of this study was to evaluate efficacy and applicability of the “intermittent hypoxic-hyperoxic exposures at rest” (IHHE) protocol as an adjuvant method for metabolic syndrome (MS) cardiometabolic components. A prospective, single-center, randomized controlled clinical study was conducted on 65 patients with MS subject to optimal pharmacotherapy, who were randomly allocated to IHHE or control (CON) groups. The IHHE group completed a 3-week, 5 days/week program of IHHE, each treatment session lasting for 45 min. The CON group followed the same protocol, but was breathing room air through a facial mask instead. The data were collected 2 days before, and at day 2 after the 3-week intervention. As the primary endpoints, systolic (SBP) and diastolic (DBP) blood pressure at rest, as well as arterial stiffness and hepatic tissue elasticity parameters, were selected. After the trial, the IHHE group had a significant decrease in SBP and DBP (Cohen’s d = 1.15 and 0.7, p < 0.001), which became significantly lower (p < 0.001) than in CON. We have failed to detect any pre-post IHHE changes in the arterial stiffness parameters (judging by the Cohen’s d), but after the intervention, cardio-ankle vascular indexes (RCAVI and LCAVI) were significantly lowered in the IHHE group as compared with the CON. The IHHE group demonstrated a medium effect (0.68; 0.69 and 0.71 Cohen’s d) in pre-post decrease of Total Cholesterol (p = 0.04), LDL (p = 0.03), and Liver Steatosis (p = 0.025). In addition, the IHHE group patients demonstrated a statistically significant decrease in pre-post differences (deltas) of RCAVI, LCAVI, all antropometric indices, NTproBNP, Liver Fibrosis, and Steatosis indices, TC, LDL, ALT, and AST in comparison with CON (p = 0.001). The pre-post shifts in SBP, DBP, and HR were significantly correlated with the reduction degree in arterial stiffness (ΔRCAVI, ΔLCAVI), liver fibrosis and steatosis severity (ΔLFibr, ΔLS), anthropometric parameters, liver enzymes, and lipid metabolism in the IHHE group only. Our results suggested that IHHE is a safe, well-tolerated intervention which could be an effective adjuvant therapy in treatment and secondary prevention of atherosclerosis, obesity, and other components of MS that improve the arterial stiffness lipid profile and liver functional state in MS patients.