Effect Of Accessory Renal Artery On Hypertension And Related Mechanisms

Background: The accessory renal artery(ARA)is a common anatomic variation of renal vessels.The reported prevalence of ARA is about 20%-80%.The relationship between ARA and hypertension has been proposed since 1951,while whether ARA could affect the blood pressure(BP)has always been dispute,and the mechanism about it has not been clearly concluded.Objective: The study was designed to compare the BP level and the target organ function of the primary hypertension(PH)patients with and without ARA,and to determine whether ARA could affect the BP level and discuss the mechanisms it involved.Method: A total of 438 patients who has been diagnosed with essential hypertension in the hypertension and heart failure ward of the First Affiliated Hospital of Dalian Medical University between 2018 and 2020 were collected.The enrolled patients were divided into the ARA group(n=200)and the PH group(n=238)according to the computed tomography angiography(CTA)of renal arteries.All patients’ general clinical data including age,hypertension duration,smoking index,body mass index(BMI),history of antihypertensive medications,diabetes and obstructive sleep apneahypopnea syndrome(OSAHS),and blood biochemistry examinations,urinary albumin creatinin ration(UACR),24-h urinary protein,24-h urinary sodium,24-h urinary potassium,24-hour ambulatory blood pressure monitoring(ABPM),24-hour Holter electrocardiogram monitoring,echocardiography,carotid artery ultrasound,flowmediated dilation(FMD),direct renin concentration(DRC),plasma aldosterone concentration(PAC)and the level of angiotensin Ⅱ were recorded.The left ventricular(LV)geometrical patterns were divided into normal geometry,concentric remodeling,concentric left ventricular hypertrophy(LVH)and eccentric LVH according to the parameters of left ventricular mass index(LVMI)and relative wall thickness(RWT).And,the concentration of plasma norepinephrine(NE)was measured by ELISA.Data analysis were performed with SPSS Statistics version 26.0.Results: There were 74.5% male,25.5% female,43.5% left ARA,34.5% right ARA,22.0% bilateral ARA in the patients with ARA in the present study.And 73.5% patients had a single ARA,26.5% patients had more than one ARA.The 24-h mean BP,daytime mean BP and nighttime mean BP of ARA group were significantly higher than those of PH group(151.60/98.11 ± 15.19/11.45 vs 145.44/94.05 ± 15.26/11.86 mm Hg,155.02/100.49 ± 15.45/11.59 vs 148.51/96.18 ± 15.83/12.17 mm Hg,139.59/90.37 ±16.51/12.74 vs 135.30/86.61 ± 16.08/13.14 mm Hg respectively,all P<0.01).Echocardiography showed that left ventricular posterior wall thickness(LVPWT),interventricular septal thickness(IVST),left atrial diameter(LAD)and abnormal LV geometrical patterns in ARA group were larger compared with those in PH group(all P<0.05).The UACR and 24-h urinary protein of ARA group were obviously higher than those of PH group(both P<0.05).The FMD of ARA group was dramatically lower than that of PH group(P<0.01).Both horizontal and vertical position DRC and Ang Ⅱ,the concentration of NE,the heart rate(HR)of ARA group were dramatically higher compared with those of PH group(all P<0.05).The difference in PAC between the two groups was not statistically significant,but there was increasing trend in ARA group(horizontal and vertical position,P=0.065 and 0.099 respectively).The BP level was positively correlated with the activity of the renin-angiotensin-aldosterone system(RAAS)and sympathetic nervous system.And,horizontal DRC was independent factor correlated with the daytime,nighttime and 24-h mean systolic blood pressure(SBP).Horizontal DRC and HR were independent factors correlated with the daytime mean diastolic blood pressure(DBP).The level of plasma NE was independent factor correlated with the nighttime mean DBP.Horizontal DRC and Ang Ⅱ were independent factors correlated with the 24-h mean DBP.Conclusion: 1.The ARA could increase the BP level of primary hypertension patients.2.Primary hypertension patients with ARA had more obvious cardiac remodeling and renal and vascular injures.3.There were activation of the RAAS and sympathetic nervous system in the population of primary hypertension with ARA,and both of them were the mechanisms that ARA affected BP.