Shelley Wood

October 05, 2009

October 5, 2009 (San Francisco, California) Nine hospitals in the US are embarking on a stent trial that will no doubt perk the attention of interventionalists and patients alike. Amid all of the larger coronary stent trials making waves at TCT 2009 last week, Dr Jason H Rogers (UC Davis Medical Center, Sacramento, CA) got up and announced the launch of the ZEN trial, testing the use of a zotarolimus-eluting stent for the treatment of erectile dysfunction.

The trial, sponsored by Medtronic, is enrolling 50 men who've failed treatment with phosphodiesterase-5 (PDE-5) inhibitors and have angiographic evidence of internal pudendal artery disease amenable to percutaneous treatment.

Speaking with heartwire after TCT, Rogers reviewed the rationale for the trial. In four out of every five men with erectile dysfunction, he notes, the etiology is vasculogenic, and erectile dysfunction itself shares a host of risk factors with coronary artery disease, including age, diabetes, hypertension, dyslipidemia, and smoking.

"Up to 70% of men with coronary disease also have erectile dysfunction," Rogers said. "The development of erectile dysfunction predates the onset of symptomatic atherosclerotic disease by approximately 36 months, [yet] erectile dysfunction is not routinely screened by vascular specialists."

Correlation Between Vascular Beds

Rogers and colleagues have already completed a pilot study, called the Pelvic Angiography in Non-Responders to PDE-5 Inhibitors (PANPI), which correlated angiographic evidence of coronary disease with pudendal arterial disease. In PANPI, 10 patients undergoing coronary angiography for CAD symptoms who also reported a poor response to PDE-5 inhibitors underwent a pelvic angiogram as well. Results showed that stenosis in the coronary arteries typically mirrored that of the pudendal artery, which ranged from a mean of 52% in the right internal pudendal artery to 60% in the left.

"We basically found a 100% correlation" between coronary artery disease and pudendal artery disease, Rogers told heartwire , "The pattern of disease is similar to that of the coronary arteries, and it appeared that it would be amenable to a stent."

Surprisingly--or not--men enrolled in PANPI were not overly interested in their coronary angiograms. "Despite the fact that we were diagnosing significant stenosis in the [left anterior descending] LAD, circumflex, and right coronary arteries, what they cared about was what the pudendal angiograms were showing," Rogers said.

Rogers noted that, to the best of his knowledge, there are no other studies looking at drug-eluting stents in the pudendal artery, although there were some early angioplasty studies that typically failed to demonstrate a long-term benefit due to problems of restenosis. Rogers would not reveal what stent is being used in ZEN, saying only that Medtronic was "leveraging technology in its inventory" and that this device was zotarolimus-eluting.

He also clarified: "This isn't stenting the penis," but rather the pudendal artery, which is located in the pelvis.

The ZEN trial represents a new opportunity for collaboration between urologists and cardiologists, Roger added--disciplines that have not interacted closely in the past. "A key message for cardiologists is that our practice is actually rich in patients with erectile dysfunction, and we don't do as good a job as we should at identifying people with erectile dysfunction," he told heartwire . "It's been shown that erectile dysfunction is a risk factor for CAD or CVD, and potentially, there may even be a therapy for this that cardiologists could deliver."

Results from ZEN are expected by 2011; enrollment has been enthusiastic, Rogers confirmed.

Rogers is a primary investigator for the ZEN trial and a paid consultant for Medtronic, Volcano, AGA medical, and Biosense Webster.