Cath Lab Digest

Let us continue down the road of the superficial femoral artery (SFA). Clearly, the data stream is slow and steady, but unfortunately, there continues to be a paucity of robust real-world data. The 2-year data for the Zilver PTX peripheral stent (Cook Medical) were presented at ISET and LINC. Michael Dake and his co-investigators should be commended on a great job with the study. My question remains, however: “Where’s the beef?” If we agree that a normal SFA has more diffuse disease, then the results presented for 5.3–5.7 cm lesions are less eye-popping than the trial’s accolades would suggest. Furthermore, if the 2-year data showing 74% patency for the stent patients are great, how can the percutaneous transluminal angioplasty (PTA) arm (non-continuous surveillance, meaning not all PTA subjects were followed for this outcome), with 58% patency, be translatable to the “real-world” patients we see everyday — when we have all “agreed” that PTA patency would likely be around 30%? There is clearly a drug effect, with the bare-metal stent producing a 2-year patency rate of 62.7% and the Zilver PTX stent, 81.2%. This difference involves the second randomization for the suboptimal PTA group and is intriguing because the 2-year endpoint is higher than what was indicated in the previous paper by Schillinger, with 54% patency at 24 months. However, the difference may again be a matter of the patients, as Schillinger’s mean lesion length was > 10 cm, and the current trial’s was < 6 cm. Intriguingly, the registry data had a lesion length of 100 mm for 900 lesions. The patency rate at 12 months was 86%, with 24-month data yet to be reported. Also of interest is the fact that 1.5% of the Zilver PTX stents had documented fracture, 36% of which occurred in patients in whom 2 stents were used.

Again, I hope that we can continue to foster the idea that science is not limited to a randomized trial of insignificant lesions, prompting us to then infer the outcome in lesions of up to 4 times’ greater length. As I stated in my previous blog, I am sure this will engender some strong feelings and arguments, but if we look at the data pragmatically, we cannot in good conscience state that the endovascular approach is currently at a strong enough level of evidence to declare that we “know” the answer unequivocally. Hence, my initial question at the outset. Without a doubt, new stent designs may change the landscape, and many of us look forward to the presentation of these data as game-changers. I hope that future trials will be “head-to-head” in a “real-world population so that we can fully discuss with our patients the best approach, benefits and risks with any lower-extremity revascularization.

So again, as a gauge, how many of us would be willing to randomize real patients with these long lesions that may only afford an angioplasty result? Given the optimal arm of the Zilver PTX stent, it seems to me that this is something that requires evaluation.

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Dr. Garcia received his B.A. and M.D. degrees from the University of Arizona. He was an Intern and Resident at Parkland Memorial Hospital, University of Texas at Southwestern in Dallas, Texas. He received his training in Cardiology at the University of Iowa Hospitals and Clinics in Iowa City, Iowa, and as an interventional cardiologist at the Beth Israel Deaconess Medical Center, Harvard Medical School. Further, he received his peripheral vascular training at St. Elizabeth’s Medical Center, Tuft’s University, Boston, Massachusetts. He then served as the Chief of Vascular Medicine and Peripheral Vascular Interventions for the Florida Heart Group in Orlando, Florida. Dr. Garcia returned to Harvard’s Beth Israel Hospital as a full-time interventional cardiologist and Director of the Peripheral Cardiovascular Program and Peripheral Interventions at the Beth Israel Deaconess Medical Center as well as the Director of the Interventional Fellowship Program. This program developed into one of the busiest in the city of Boston, performing over 600 peripheral procedures per year.

Dr. Garcia has now returned to St. Elizabeth’s Medical Center as Chief of the Section of Interventional Cardiology and as Associate Director of the Vascular Medicine Program. Dr. Garcia’s work has largely focused on arterial occlusion-reperfusion models and the efficacy of therapeutic modalities or interventions with regard to free radical generation or endovascular stenting outcomes. Dr. Garcia continues his research interests in a wide variety of studies including acute MI studies, unstable angina studies, interventional trials, peripheral interventional trials, angiogenesis trials, imaging modality studies, and numerous device trials for both the coronary and peripheral circulations. His work has been presented in numerous manuscripts, abstracts, textbooks and textbook chapters.