Kidney Week

Abstract: SA-PO992

Renal Functional Reserve Mirrors the Sympathetic Overdrive Influence on the Heart

Session Information

• Hypertension and CVD: Mechanisms - II
  October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Hypertension and CVD

• 1403 Hypertension and CVD: Mechanisms

Authors

• Damianaki, Aikaterini A., Hippokration Hospital of Arhens, Athens, Greece

Aikaterini A. Damianaki,

• Dimitriadis, Kyriakos, First Cardiology Clinic, University of Athens, Hippokration Hospital, Athens, Greece

Kyriakos Dimitriadis,

• Alexakou, Zoe, Hippokration Hospital of Arhens, Athens, Greece

Zoe Alexakou,

• Chalkia, Aglaia, Hippokration Hospital of Arhens, Athens, Greece

Aglaia Chalkia,

• Tsioufis, Konstantinos, First Cardiology Clinic, University of Athens, Hippokration Hospital, Athens, Greece

Konstantinos Tsioufis,

• Petras, Dimitrios I., Hippokration Hospital of Arhens, Athens, Greece

Dimitrios I. Petras,

Background

Renal functional reserve (RFR) refers to the capacity of the kidney to increase the Glomerular Filtration Rate (GFR) under the influence of certain stimuli. It is a promising diagnostic tool for assessing the risk of Acute Kidney Injury and of Chronic Kidney disease development in specific populations. The aim of our study was to assess the relation of RFR with diverse clinical parameters in normotensive patients with eGFR>60ml/min/1.73m²and without any evidence of kidney damage (proteinuria, anatomic lesion etc).

Methods

15 normotensive subjects (mean age=52 years, BMI= 26 kg/m², office systolic/diastolic BP =138/88 mmHg, ABPM 120/76mmHg) were included. All subjects underwent the exercise treadmill stress test, 24hour ABPM, office BP measurements, kidney ultrasound and ACR test. All subjects were fasted for 8 hours and then baseline hydration status was recorded using bioimpedance analysis. Basal GFR was measured after hydration and stress GFR was achieved after ingestion of oral protein 1g/kg as cooked meal. Basal and Stress GFR were determined by Creatinine Clearance = Urine Creatinine/Serum Creatinine x Urine Volume/time× 1.73/BSA). RFR was calculated as Stress GFR – Basal GFR. Patients having adequate renal reserves considered as having values of RFR greater than 30ml/min/1.73m²

Results

There was no correlation of RFR values with respect to family history of hypertension, smoking, age, BMI or office BP. In contrast,patients with higher RFR values, achieved lower maximum systolic BP during the treadmill test (p<0.05) (175.7 ± 9.75 mmHg vs 176.2±22.48mmHg). Additionally, a statistically significant positive correlation was found between RFR values and maximum heart rate (HR) during treadmill test (r=0.517, p=0.048).

Conclusion

RFR is related to treadmill exercise maximum systolic BP in normotensive patients and appears to correlate with maximum HR. These findings underlie the pleiotropic effects of sympathetic nervous system in kidneys and their long term influences in kidney function. Treadmill test could be used to identify normotensive patients with normal eGFR who may have susceptibility to renal injury.