Nephrectomy improves both antihypertensive requirement and left ventricular mass for pediatric renal hypertension

Abstract

Background: Renal hypertension causes left ventricular (LV) hypertrophy leading to cardiomyopathy. Nephrectomy has been utilized to improve blood pressure and prepare for kidney transplantation in the pediatric population. We sought to investigate antihypertensive medication (AHM) requirement and LV mass in patients undergoing nephrectomy with renal hypertension.

Methods: We performed a single institution retrospective review from 2009 to 2021 of children who have undergone nephrectomy for hypertension. Primary outcome was decrease in number of AHM. Secondary outcomes included change in LV mass and elimination of AHM. LV mass was measured using echocardiogram area-length and linear measurements. Non-parametric analyses were utilized to assess significance.

Results: Thirty-one patients underwent nephrectomy. Median age was 12.5 years (0.8-19 years). Median of 3 AHM (range 1-5 medications) were used pre-operatively and patients had been managed for median 2.5 years. Twenty-nine had preoperative echocardiogram. Forty-eight percent of patients had LVH at nephrectomy. Median AHM after surgery was 1 (range 0-4 medications) at 30 days and 12 months, (p < 0.001). By 12 months after nephrectomy, 79.2% of patients had decreased the number of AHM. Eight (26%) patients were on no AHM 30 days after surgery, and 13 (43%) at 12 months. Systemic vascular disease and multicystic dysplastic kidney were the only factors associated with lack of improvement in AHM (p = 0.040). Fourteen patients had pre- and post-operative echocardiogram and 11 (79%) had improvement in LV mass (p = 0.016, 0.035).

Conclusions: Nephrectomy is effective in improving LV mass and reducing AHM for children with renal hypertension. Improvement is less likely in patients with systemic vascular disease and multicystic dysplastic kidneys. A higher resolution version of the Graphical abstract is available as Supplementary information.

Keywords: Antihypertensive medications; Cardiomyopathy; Chronic kidney disease; Left ventricular hypertrophy; Nephrectomy; Renal hypertension.