Prognostic value of low ankle-brachial index in patients with resistant hypertension

Abstract

In the presence of resistant hypertension, patients have a significantly higher risk of stroke, myocardial infarction, kidney disease, heart failure, and death than patients with elevated blood pressure. Increased arterial stiffness is an important factor in determining cardiovascular risk. Peripheral artery damage is a target organ lesion, and its presence puts the patient at high or very high risk. The simplest non-invasive method of detecting peripheral vascular damage in patients is to determine the ankle-brachial index (ABI). Aim. To detect the frequency of damage to the lower extremity peripheral arteries by determining the ankle-brachial index and its impact on the subsequent prognosis in patients of older age (>55 years) with resistant hypertension using automatic blood pressure monitors. Materials and methods. The object of the study were patients with hypertension aged 55 years – 150 people with elevated blood pressure of the 3rd degree and 20 healthy people of the same age. The study included only those patients who did not have clinical symptoms of peripheral vascular disease, type 2 diabetes mellitus. Determination of the ABI was performed by an automatic device. Results. The frequency of femoral artery lesions detection by measuring blood pressure on the brachial and legs in asymptomatic patients with resistant hypertension was 14.0 %. For a detailed analysis, we divided all patients with hypertension depending on the value of the ABI into two subgroups: subgroup A included patients (n = 129) with an ABI value >0.9, subgroup B (n = 21) – with the value of ≤0.9. In patients with resistant hypertension and peripheral arterial disease, the more common factors were: longer duration of hypertension, the presence of isolated systolic hypertension and a lower level of glomerular filtration rate. Decreased ABI (≤0.9) in patients with resistant hypertension was associated with a 1.4-fold increased risk of adverse cardiovascular complications and a 1.9-fold increased risk of all-cause mortality. Conclusions. In patients with resistant hypertension, a reduced ankle-brachial index was associated with a 1.4-fold increased risk of adverse cardiovascular complications and a 1.9-fold increased risk of all-cause mortality.

Keywords

• arterial hypertension
• ankle-brachial index
• vascular stiffness