Frequency of Acccessory Renal Arteries Diagnosed by Computerized Tomography

Effect of Accessory Renal Arteries on Essential Hypertension and Related Mechanisms

BACKGROUND

This case-control study aimed to determine whether there were differences between patients with essential hypertension with accessory renal arteries (ARAs) and those without ARAs.

METHODS AND RESULTS

The enrolled patients with essential hypertension were divided into the ARA group (n=200) and control group without ARAs (n=238). After propensity matching, 394 patients (197 in each of the 2 groups), were included. The 24-hour BP (4.33/2.43 mm Hg) and daytime BP (4.48/2.61 mm Hg) of patients in the ARA group were significantly higher than those of the control group (P<0.05). The flow-mediated dilation was lower in the ARA group (5.98±2.70 versus 5.18±2.66; P<0.05). In correlation analysis, the horizontal plasma aldosterone concentration had the highest correlation with 24-hour, daytime, and nighttime systolic BP (r=0.263, 0.247, and 0.243, respectively; P<0.05) and diastolic BP (r=0.325, 0.298, and 0.317, respectively; P<0.05). As for multivariate regression analysis, plasma aldosterone concentration was a significant risk factor for elevated 24-hour, daytime, and nighttime systolic BP (β=0.249 [95% CI, 0.150-0.349], 0.228 [95% CI, 0.128-0.329], and 0.282 [95% CI, 0.187-0.377], respectively; P<0.05) and elevated diastolic BP (β=0.289 [95% CI, 0.192-0.385], 0.256 [95% CI, 0.158-0.353], and 0.335 [95% CI, 0.243-0.427], respectively; P<0.05). Direct renin concentration was also a risk factor for 24-hour and daytime BPs, whereas heart rate was a risk factor correlated with 24-hour, daytime, and nighttime diastolic BP (all P<0.05). For the mixed-effects model for repeated measures, the results were similar to results of the multivariate regression analysis (all P<0.05).

CONCLUSIONS

ARAs could contribute a higher BP of patients with essential hypertension and might promote the development of essential hypertension. The mechanism might be related to overactivation of the renin-angiotensin-aldosterone system and sympathetic nervous system.

Relationship between accessory renal arteries and resistant hypertension: A cohort study

BACKGROUND

Resistant hypertension (RHT) is a major health care concern affecting 20 to 30% of hypertensive patients and increasing cardiovascular risk. Recent renal denervation trials have suggested a high prevalence of accessory renal arteries (ARA) in RHT. Our objective was to compare the prevalence of ARA in RHT vs. non-resistant hypertension (NRHT).

METHODS

Eighty-six patients with essential hypertension who benefited from an abdominal CT-scan or MRI during their initial workup were retrospectively recruited in 6 French ESH (European Society of Hypertension) centers. At the end of a follow-up period of at least 6 months, patients were classified between RHT or NRHT. RHT was defined as uncontrolled blood pressure despite the optimal doses of three antihypertensive agents of which one is a diuretic or similar, or controlled by ≥ 4 medications. Blinded independent central review of all radiologic renal artery charts was performed.

RESULTS

Baseline characteristics were: age 50±15 years, 62% males, BP 145±22/87±13mmHg. Fifty-three (62%) patients had RHT and 25 (29%) had at least one ARA. Prevalence of ARA was comparable between RHT (25%) and NRHT patients (33%, P=0.62), but there were more ARA per patient in NRHT (2±0.9) vs. RHT (1.3±0.5, P=0.05), and renin levels were higher in ARA group (51.6±41.7 mUI/L vs. 20.4±25.4 mUI/L, P=0.001). ARA were similar in diameter or length between the 2 groups.

CONCLUSIONS

In this retrospective series of 86 essential hypertension patients, we found no difference in the prevalence of ARA in RHT and NRHT. More comprehensive studies are needed to answer this question.