Physiological Study of the Efficacy and Mechanistic Effects of Alcohol Renal Denervation

AIM1: The first aim of the study will be to determine the efficacy of chemical renal
denervation in altering renal sympathetic nerve activity. This objective will be assessed by
change in urinary catecholamines and sympathetic activity in the kidney 8 weeks post renal
denervation (+/- 7 days). Specifically the investigators will compare the change in peak
concentrations of 6-18F-fluorodopamine radioactivity in the renal cortex after renal
denervation. A finding of a reduction in 6-18F-fluorodopamine radioactivity in the renal
cortex will suggest that the chemical denervation has reduced sympathetic innervation in the
kidney. Our secondary assessment of efficacy will be via change in excretion of urinary
norepinephrine, assessed by 24 hour urine collection. In addition, we will measure plasma
norepinephrine and metanephrine concentrations to isolate the systemic contribution from the
kidney. Again a reduction in sympathetic innervation of the kidney by renal denervation will
reduce norepinephrine excretion.

AIM 2: The second aim of the study will be to utilize high resolution physiological testing
to identify how chemical renal denervation alters the integrative regulation of blood
pressure. The proposal entails using classic physiological techniques to examine blood
pressure regulation, which are well established in the PI's laboratory. Briefly the testing
will include a detailed assessment of hemodynamics, autonomic function, neurohormonal volume
control, renal blood flow, endothelial function and vascular compliance. While mean blood
pressure is the product of cardiac output × total peripheral resistance, reductions in blood
pressure may be via a number of divergent mechanisms following renal denervation. Following
this study, the investigators will be able to characterize how blood pressure is reduced, and
whether there is individual variability in the response.

Experimental protocol. All patients will be required to undergo a battery of testing at
baseline, and at 8 weeks post renal denervation. At the 8 week appointment patients will be
followed up again at 6 and 12 months with an office blood pressure measurement, ambulatory
blood pressure monitoring, vital signs, adverse events, assessment of renal anatomy (at 6
months and assessment of renal function.

Autonomic function testing and blood volume (Baseline, week 8): Prior to testing all patients
will consume a standardized isocaloric diet provided to them for 3 days. The diet will follow
the principles of the DASH diet (Dietary Approaches to Stop Hypertension). In addition,
patients will avoid caffeine and alcoholic beverages for ≥24 h prior to testing, other fluid
intake will be ad libitum. All studies will take place in the morning after a >12h fast. A
fasting resting blood sample will be taken for measurement of FGF-23, electrolytes,
hemoglobin, hematocrit, insulin and glucose. Patients will be instructed to withhold
medication on the morning of this visit and a urine sample will be collected to confirm
medication compliance. Autonomic function tests including spontaneous and controlled
breathing, Valsalva, cold pressor test, submaximal handgrip to fatigue with post-exercise
circulatory arrest, 30º and 60º head-up tilt will be performed. Measurements will include:
MSNA recorded from the peroneal nerve by microneurography, beat-to-beat arterial pressure
(Nexfin, BMEYE), brachial blood pressure will be measured by electrosphygmomanometry
(Suntech), heart rate (HR, lead II of the ECG), cardiac output (Qc, modified acetylene
rebreathing method), stroke volume (SV=Qc/HR), renal artery blood flow from doppler and total
peripheral resistance (TPR=mean BP/Qc). Neurohumoral measurements include: catecholamines,
plasma renin activity, aldosterone, and vasopressin will be performed at baseline and after
20 minutes of 60º head-up tilt. Sympathetic vascular transduction will be determined by the
simultaneous measurement of forearm blood flow and vascular conductance (Doppler ultrasound)
and MSNA at baseline. Blood volume will be measured in the sitting position by the modified
carbon monoxide rebreathing technique.

Vascular, ventricular and endothelial function testing (Baseline, 8 weeks, 6 months): As
systolic blood pressure is largely determined by arterial stiffness and afterload the
investigators will measure the effect of renal denervation in a number of ways. Arterial
stiffness will be measured using the SphygmoCor device from which the measurement of
peripheral and central pulse wave velocity, augmentation index and central blood pressures
will determined. In addition, based on the Windkessel model, total arterial compliance will
be calculated from stroke volume/pulse pressure, effective arterial stance will be calculated
from end systolic pressure/stroke volume. Aortic age, will be derived using the Modelflow
method and vascular compliance as beta stiffness. Two- and three-dimensional echo for left
ventricular volumes and pulse wave Doppler, Tissue Doppler parameters, and color M-Mode
Doppler for assessment of diastolic function will also be performed, using a standard echo
machine (Phillips, iE33). Offline analysis for torsion and strain will be performed using
commercially available software (Qlab). Finally, brachial artery flow-mediated
(endothelium-dependent) and nitroglycerin-induced (endothelium-independent) vasodilatation
will be measured using a high-resolution Doppler ultrasound machine in the supine position.

Positron emission tomography (PET) imaging (Baseline, 8 weeks): Subjects who agree to
participate in our study will travel to the National Institute of Neurological Disorders and
Stroke, Bethesda Maryland, and undergo PET imaging of sympathetic activity in the kidney
using PET/CT scanner (Siemens).

9.1 Please indicate the inclusion criteria for enrollment: Six patients will participate in
this study. Patients who present with uncontrolled hypertension (classified as clinic
systolic blood pressure not at target level >140mmHg) to their primary care provider,
emergency room (ER), specialist hypertension clinic or urgent care center will be asked to
participate.

Inclusion criteria include:

1. Patient presents with treated or untreated hypertension.

2. Adults aged 18-75 years, male or female

3. Patient has a clinic systolic blood pressure >140mmHg (average of 3 measurements), or
>135mmHg in patients with type II diabetes

4. Patient has a daytime mean systolic blood pressure of ≥135 and diastolic blood
pressure ≥85mHg based on 24 hours ambulatory blood pressure monitoring

5. Investigator judges that the subject can be managed safely for up to 12 weeks (4 weeks
run-in plus 8 weeks post-treatment) with the use of standard background regimen of
losartan/hydrochlorothiazide; patients with true resistant hypertension will be
required to maintaining current antihypertensive regime for the duration of the study.

Exclusion Criteria. Any patient who meets any of the following exclusion criteria will not
be eligible for the study.

1. Patient has known or suspected secondary hypertension

2. Use of systemic drugs that may be used for the treatment of hypertension, for a
non-hypertension indication for the trial, (e.g. atrial fibrillation/atrial flutter,
heart failure, or calcium channel blocker for heart rate control).

3. Renal artery stenosis ≥ 50% diameter stenosis, or aneurysm(s)

4. Patients with atrial fibrillation.

5. Patient has type 1 diabetes

6. Patient has type 2 diabetes and evidence of peripheral neuropathy

7. History of previous stenting or balloon angioplasty of the renal arteries.

8. Untreated hypothyroid or hypo-parathyroid.

9. Orthostatic hypotension defined as >20 mmHg of systolic blood pressure and/or more
than 10 mmHg in diastolic blood pressure fall after standing for 3mins

10. Renal artery anatomy as assessed by imaging (CT-angiogram or, MR angiogram or renal
angiogram) meeting the following criteria:

1. Single renal artery or two renal arteries, if either has a diameter of < 5 mm or
> 7 mm or a length of < 11 mm,

2. Accessory renal arteries with diameter > 2.0 mm and < 5.0 mm,

3. Excessive renal artery tortuosity based on Investigator judgment,

4. Moderate or severe, and diffuse renal artery calcification, and/or

5. Renal anatomic renovascular abnormalities (as assessed by renal imaging) that
would increase the risk of renal catheterization.

11. Occlusive peripheral vascular disease that would preclude percutaneous access for the
procedure.

12. Patient is known to have a unilateral non-functioning kidney or unequal renal size (>
2cm difference in renal length between kidneys).

13. Single kidney, kidney tumor, urinary tract obstruction, or other anatomic abnormality.
Note: Simple renal cysts are not an exclusion.

14. Previous renal denervation.

15. History of renal transplantation.

16. Estimated eGFR (by the CKD-Epi formula) ≤45 mL/min per 1.73 m2, or on chronic renal
replacement therapy. Patients with eGFR of <60 mL/min per 1.73 m2 will undergo
additional renal function monitoring post procedure and/or contrast exsposure.

17. Unexplained hypokalemia (i.e. K < 3.5 mEq/L in patients not on a potassium-wasting
diuretic).

18. Patient in whom an ABPM device cannot be used due to arm size (>50 cm arm
circumference) or other reasons as identified by the Investigator or study
coordinator.

19. Patient with severe cardiac valve stenosis for which, in the opinion of the
Investigator, a significant reduction of blood pressure is contraindicated.

20. Heart failure greater than asymptomatic, New York Heart Association Functional
Classification, class I, stage B heart failure

21. Patient with history of myocardial infarction, unstable angina pectoris, or stroke
during the 6 months prior to screening

22. Known primary or secondary pulmonary hypertension.

23. Active infection.

24. Patient requiring chronic oxygen support or has severe COPD.

25. Patient has known hypersensitivity to contrast agents that cannot be adequately
pre-medicated

26. A known hypersensitivity to Dehydrated Alcohol Injection.

27. Platelet count < 75,000/microliter and/or known bleeding diathesis or coagulopathy at
time of screening.

28. Receiving anticoagulant drugs (e.g., warfarin, dabigatran, rivaroxaban, apixaban,
edoxaban, or low molecular weight heparins), that in the opinion of the investigator,
would affect the safety of the trial procedure. Use of antiplatelet drugs such as
aspirin and/or thienopyridines (e.g., clopidogrel) are permitted.

29. Patient has current problems with substance abuse (e.g. alcohol, illegal drugs, etc.).

30. Patient on high dose of steroids or immunosuppressant therapy.

31. Patient has a history of myocardial infarction, unstable angina pectoris, or stroke
during the 3 months prior to screening.

32. Patients with a history of pre-eclampsia

33. patients with fibromuscular dysplasia

34. patients with history of pyelonephritis within 6 months

35. patients with history of recurrent (> one episode) kidney stones or history of kidney
stones within the last year

36. Pregnant or nursing or planning to become pregnant during the trial time period.

Note: If subject is of childbearing potential, as defined in the protocol, agrees to
use of contraception.

37. Any acute or chronic condition that the investigator believes will adversely affect
the ability to interpret the data or will prevent the subject from completing the
trial procedures, or has a life expectancy of < 12 months.