Desperate Times, Desperate Measures: The ZEN trial – Will it Ultimately Flop?
Pondering Across the Pond
Desperate Times, Desperate Measures: The Zen trial — Will it Ultimately Flop?
At TCT this year, I realized that corporate agenda and big business can drive ideas into the realms of uncertainty. Also, interventionalists seem hell-bent on creating a procedure for every ill. My main point of reference for this is the ZEN trial. For those of you that have no idea what I am getting at, this trial involves stenting a small artery that supplies some of the blood to the penis! As I listened to the forecasts and industry projections for this billion dollar market, I did think, why are CARDIOlogists getting involved in erectile dysfunction? Is that not a bit like going to the dentist with hemorrhoids?? We were then treated to a case presentation, where an internal pudendal artery was stented. I might add that the guidewire was badly placed and hardly down the targeted vessel and the improved “tissue blush” looked more like contrast leak from a small perforation.
I am intrigued to know how the outcome of this trial will be measured? Is there a scale for erectile quality? How will this be judged against baseline and how do we know that this erection is better than it would have been without a procedure, in the presence of a scantily clad lingerie model!? On a more serious note, in order to test this properly there will need to be a blinded, sham procedure controlled study of some kind. Outcome measurements will have to provide physiological evidence of improved erections (not just anecdotal, qualitative, questionnaire evidence) I suppose they could measure penis-brachial pressure index (don’t laugh – it exists!)
My other problem with this whole area is that the erectile process is one of the most complicated expressions of physiology within the human body. Have a flick through this 46 page, with 400 references, endocrinology review to see how complex it really is. The majority of atherosclerotic or blood supply problems actually involve vasomotive disorders or micro-vascular dysfunction (A bit more like the heart and certainly not the best substrate for a stent!)
http://edrv.endojournals.org/cgi/content/full/22/3/342
This philosophy of “stent” to treat is short sighted, but the desire to make money in new markets appears to be all consuming. I saw dollar signs that night, reflected in the eyes of everyone involved with this concept.
Let me know your honest thoughts on this and how you would plan a scientifically robust trial to prove the effect (beyond doubt) of pudendal artery stenting. You may also like to tell me what happens when there is stent thrombosis! Nasty!







