The primary risks of the renal denervation procedure are similar to the risks of all diagnostic procedures requiring catheterization of the arteries of the body. The following are potential risks of the catheterization procedure (including renal angiogram):

Uncommon < 10% (less than 1 in 10 chance), temporary and not severe unless otherwise indicated

  • Nausea or vomiting 
  • Complications associated with the use of any pain or anxiety medication during or after the procedure 
  • Complications at catheter insertion site in the groin, including: 
    • Pain 
    • Bruising 
    • Hematoma (collection of blood outside a blood vessel)

Rare < 1% (less than 1 in 100 chance), temporary and not severe unless otherwise indicated

  • Heart rhythm disturbances, including bradycardia (a slowed heart rate) 
  • Embolism - Formation and dislodgement of a blood clot or dislodgement of cholesterol/plaque within the blood vessel, which travels downstream into small vessels, blocking blood flow and causing temporary or permanent damage to organs in the body. Clots are known to cause heart attack, stroke, kidney damage, or threaten circulation to arms or legs and may ultimately lead to incapacitation or death. 
  • Complications at catheter insertion site in the groin, including:
    • Pseudoaneurysm (injury to the artery wall resulting in a build-up of blood under the skin) 
    • Arteriovenous fistula (an abnormal connection or passageway between an artery and a vein)
    • Vascular complications requiring surgery
  • Perforation or dissection (a hole or tear in your blood vessel) of a blood vessel, such as the renal artery 
  • Complications associated with the contrast agent used during the procedure, e.g., serious allergic reaction or reduced kidney function

Very Rare < 0.1% (less than 1 in 1000 chance)

  • Complications at catheter insertion site in the groin
    • Infection 
    • Significant bleeding
  • Retroperitoneal bleeding (bleeding into the abdominal space)
  • Cardiopulmonary arrest 
  • Death

There are additional risks that could possibly be associated with the denervation procedure/response to treatment. These complications have not yet been quantified. These potential risks may include:

  • Pain – during or after the procedure that may require treatment with pain medications. 
  • Damage to one or both kidneys, loss of kidney function, and/or need to remove a kidney. If severe enough, this could require dialysis. 
  • Damage to the blood vessel wall or other body structures from the delivery of energy, e.g., renal artery stenosis (narrowing of blood vessel), spasm, or aneurysm (ballooning of blood vessel wall). 
  • Hypertension (blood pressure too high) 
  • Hypotension (blood pressure too low) 
  • Hematuria (blood in urine) 
  • Hemorrhage (significant blood loss) 
  • Proteinuria (increased amount of protein in urine) 
  • Allergic and/or adverse reaction from insertion of foreign body (i.e., catheter) 
  • Electrolyte disturbances (e.g., changes in the amount of salt in blood/urine) 
  • Skin burn

There are additional risks that could possibly be associated with the tests and procedures performed for the clinical study.


The device has not been evaluated in patients who are pregnant, nursing, or plan to become pregnant.

All rights reserved. Medtronic, Medtronic logo and Further, Together are trademarks of Medtronic. All other brands are trademarks of a Medtronic company.  For distribution only in markets where the Symplicity Spyral™ multi-electrode renal denervation catheter and Symplicity G3™ renal denervation RF generator have been approved. Not for distribution in the USA, Japan or France.