All DES are not the same – they differ in stent platform, drug and polymer. With this in mind, Dr Ki-Bae Seung of Korea presented his work on comparing Zotarolimus-eluting (ZES) and Sirolimus-eluting (SES) stents......
Daily News 3, CIT2010, April 1st
CATOS: A Randomized Comparison of Zotarolimus-Eluting Stent vs. Sirolimus-Eluting Stent for Percutaneous Coronary Intervention in Chronic Total Occlusions, Seung
Featured Clinical Trials I: First Report Investigations, Function Hall B, 5.00-5.10pm
All DES are not the same – they differ in stent platform, drug and polymer. With this in mind, Dr Ki-Bae Seung of Korea presented his work on comparing Zotarolimus-eluting (ZES) and Sirolimus-eluting (SES) stents. Different inputs can produce different outputs and different lesion subsets can produce different outputs, complicated further by coronary artery histopathology. Dr Seung’s groups hypothesis was that ZES may be inferior to SES in terms of late luminal loss, but have similar clinical outcomes compared with SES. In addition, use of ZES in CTO lesions may have better safety outcomes in terms of late stent malapposition, aneurismal change, stent fracture and stent thrombosis.
So to compare the efficacy and safety between ZES and SES in patients with CTO, a prospective, multicenter randomized clinical trial was designed and conducted from 4/07 to 10/09, amongst patients at the centers of the Catholic University of Korea. One hundred patients were randomized to either Endeavor (50) or Cyper (50) stents, clinical follow-up was conducted at twelve months and angiographic and IVUS follow-up at nine months. The major inclusion criterion was a CTO lesion with an estimated duration of total occlusion greater than three months. The primary endpoint was in-segment late luminal loss on CAG at nine months. Issues of efficacy and safety made up the secondary endpoint. He outlined procedural factors of the study: antiplatelet regimen pre-, during and after discharge; and stenting procedure. His summary of results stated that ZES is comparable to SES in CTO patients in terms of efficacy concerns such as in-segment late luminal loss and composite of MACE. Primary endpoints between the stents then were not different. However Dr Seung concluded that in terms of safety concerns such as stent malapposition, fracture and /or thrombosis, ZES is superior to SES in CTO patients. He presented these conclusions with caution and added there was a need for much more long-term clinical data in both stents. The moderating panel agreed that it was hard to draw statistically derived conclusions from the trial due to the small numbers involved and suggested using the data to design another trial using IVUS as an endpoint tool.
Long-term Vascular Changes after Drug-Eluting Stent Implantation Assessed by Serial Volumetric Intravascular Ultrasound Analysis: A Substudy of DES-FU, Kang
Featured Clinical Trials I: First Report Investigations, Function Hall B, 5.45-5.55pm
On behalf of the Cardiology Department, University of Ulsan College of Medicine, Seoul, Korea, Dr Soo-Jin Kang presented the results of a non-randomized study based on the suggestion that delayed arterial healing is a potential mechanism for late catch-up in vessel intimal growth. There are few long-term studies demonstrating late vascular changes including intimal hyperplasia(IH), late stent malapposition and remodeling. Her team set out to report the serial IVUS findings (at baseline, early “6 month” and late “2 year” follow-ups) in patients treated with DES without clinical events between stenting and late follow-up. SES (99) and PES (44) were used for the procedures and complete angiographic and IVUS data (3D-IVUS volumetric analysis) were available in 135 patients with 143 lesions. This was not a randomized comparison of SES vs PES and as sample size was small, there was a potential for selection bias. The conclusions reached were that although IH continued to increase beyond six months, the rate of IH and luminal loss attenuated over time with only a modest late catch-up from six months to two years.
My Vision: Only Few and Carefully Selected Patients, Fajadet
EuroPCR at CIT, Debate on PCI for Left Main Stenosis, Plenary Hall A, 4.15-4.25pm
In the ongoing debate on the role of PCI or CABG in left main disease, Professor Jean Fajadet of the Pasteur Clinic, Toulouse, France represented the European experience. He asked the question: Why is surgery considered as the standard of care? Long-term survival advantage, better results after bilateral IMA grafting and better results after total arterial grafting, were his proposed answers to that question. Yet in the SYNTAX study, of 85 total sites across the US and Europe, revascularization was achieved in only 20% of cases! He proposed a model of the basics of decision-making with clinical judgment as the pivotal multifactorial point. Contributing to this clinical judgment were: knowledge, expertise, technology and the patient. Knowledge of outcomes is available from many sources but only two RCTs exist on the subject of DES vs. CABG in the left main since 2002, compared to a lengthy list of registries or comparisons with DES. The complexity of a lesion based on SYNTAX score determines procedure and outcomes - LMCA disease is characterized by a distal location in >70% of cases, calcified in >50% of cases and a greater than 70% incidence of MVD. The presence of diabetes also dramatically influences MACE rates in PCI compared to CABG. The second contributing factor of local expertise of the heart team will influence the clinical judgment. The capacity of clinicians to share experiences and techniques and come to a collegial consensus on patient care is paramount. Thirdly, evolution of technology in surgical and PCI fields is ongoing. DES progress from generation to generation, whether they be biodegradable polymer or polymer free, and new antiplatelet agents continue to surface. The interest in hybrid procedures had been evidenced in an earlier lecture. Finally, the global appraisal of the patient and the myriad of contributing factors will influence the physician’s clinical judgment. Age, gender, socio-cultural considerations, diabetes and other risk factors of CAD, previous intervention, COPD, renal failure, angiographic characteristics such as location, complexity, number and severity of lesions – are some of the points to be considered.
So from these criteria, indications for PCI vs CABG can be drawn. Professor Fajadet outlined these in his presentation. In summary, the best indication for PCI is non-distal LM stenosis. There are reasonable indications for PCI in both elderly and younger patients determined by a lengthy list of contributing factors drawn from his earlier points. Surgery should be preferred though, in those cases usually with complications of MVD, calcification, reduced LV function and diabetes for example. Ultimately, patient selection is crucial using the four areas of investigation he alluded to, based also on medical-surgical consultation and the ethics of the information provided.