By all measures, CCSVI treatment or TVAM (Transvascular Autonomic Modulation) is safe. The data to support safety of the procedure is well documented in the medical literature. Fundamental to treatment is jugular angioplasty (dilation of a balloon within the jugular vein). Angioplasty has been widely used for decades to treat stenosis of the veins and balloons serve as the platform for novel procedures such as renal denervation. Angioplasty has been widely accepted by doctors worldwide to be safe and all scientific evidence confirms this to also be true in regards to jugular veins.
Balloon angioplasty will mark its 40th anniversary next year. While balloon angioplasty is a critical component of modern healthcare, it has met strong resistance at each stage of its development and applications to specific diseases. This was true over 30 years ago, when angioplasty was first used in the coronary artery, followed by the femoral artery and then the venous narrowing encountered with dialysis vascular access. Skepticism on the efficacy of balloon angioplasty in new applications is understood as the physiologic impact on the target organ can be tremendously variable. The vessels themselves are far more uniform. The potential complications of balloon dilation of a coronary artery have broad commonality to those experienced when angioplasty a narrowed AV fistula used for dialysis access.
The FDA in fact recognizes the “cumulative” nature of angioplasty safety. The FDA considers angioplasty balloons as Class II devices. This means efficacy must be demonstrated but preliminary safety studies are not required. The most recent indications issued by the FDA are for balloon dilation of narrowing of venous of dialysis access. The rates of complications for such procedures are well established and accepted ranging from 3-8.5%. To put this risk in perspective we can look to an angioplasty procedure that happens almost 5000 times a day in the US as a point of reference. Community hospital coronary angioplasty has a significant adverse event rate of 15% and serves as a useful bar against which to gauge risk.
Jugular vein angioplasty is not unusual in the care of a patient receiving dialysis. In the last few years a surge in jugular angioplasty procedures has occurred with a new entity, CCSVI being described in 2009 by Zamboni. The cumulative nature of balloon angioplasty safety appears to have been forgotten by the FDA as they have issued a warning about jugular angioplasty being a high risk procedure. The warning did not mention the available scientific data.
While the efficacy of jugular angioplasty can be scientifically questioned the safety cannot. Historically angioplasty in a vein is associated with safety, adverse events expected in 3-8.5% of cases. Zambonis first case control study demonstrated an absence of major adverse events. Six subsequent studies with a purpose of determining the safety of jugular ballooning have been published:
- http://www.ajronline.org/doi/abs/10.2214/AJR.12.8938
- http://jevtonline.org/doi/abs/10.1583/11-3440.1
- http://www.jvir.org/article/S1051-0443(11)01302-9/abstract
- http://www.jvir.org/article/S1051-0443(12)00708-7/abstract
- http://phleb.rsmjournals.com/content/early/2020/04/05/0268355513481766.abstract
- http://phleb.rsmjournals.com/content/25/6/286.abstract?sid=d52a1922-36d9-4867-aaa4-3f6dd839ca9b
The significant adverse event rate is ranged from 0-3.2% in studies designed to assess safety. Well below the accepted threshold for safety. Shortly after the initial introduction of CCSVI treatment several rare severe complications occurred including patient deaths. This is seen when new techniques are introduced. It is important to note that these severe adverse events either were the result of stent placement or a bleeding complication. Pradaxa was the blood thinning agent used in several of the bleeding complications following CCSVI treatment. Postmarked reports of bleeding risk with this medication and the rare complications following treatment of CCSVI initiated reevaluation. As of April 2013, it has been over two years since a serious adverse event has occurred in association with CCSVI care.
The perception of jugular angioplasty is that it is high risk. This is counter to the existing medical literature and the FDA’s categorization of angioplasty balloons as Class II devices. It is likely the debate over the efficacy of the procedure has influenced the perception of the procedure. This is evidenced by a publication regarding CCSVI by the Italian MS group, known critics of the procedure. They describe the observed adverse event rate of 3.5% as being high risk, despite falling well within range accepted as safe. This erroneous conclusion on its own becomes even more dubious upon closer examination. Review of adverse events attributable to the procedure include things such as excessive bleeding from a bed sore or hypertension following unrelated surgery. They also attribute a death to the procedure, the patient died of a myocardial infarction 10 weeks after the procedure. This remains as the worst case scenario for safety of jugular ballooning in the published literature and even it demonstrates an acceptable adverse event rate.
The efficacy of jugular angioplasty will continue to be scientifically debated. This is justifiably so as efficacy always requires a higher level of data and should not depend on the cumulative nature of similar therapies. Regarding safety, all available data supports jugular angioplasty as safe. Continued statements on the high risk of these procedures serve no purpose other than to inhibit further knowledge and health.
