Distal versus conventional radial access for coronary angiography and intervention: Design and rationale of DISCO RADIAL study.

BACKGROUND: Transradial access (TRA) has become the default access method for coronary diagnostic and interventional procedures. As compared to transfemoral access, TRA has been shown to be safer, cost-effective and more patient-friendly. Radial artery occlusion (RAO) represents the most frequent complication of TRA, and precludes future coronary procedures through the radial artery, the use of the radial artery as a conduit for coronary artery bypass grafting or as arteriovenous fistula for patients on hemodialysis. Recently, distal radial access (DRA) has emerged as a promising alternative to TRA, yielding potential for minimizing the risk of RAO. However, an international multicenter randomized comparison between DRA, and conventional TRA with respect to the rate of RAO is still lacking. TRIAL DESIGN: DISCO RADIAL is a prospective, multicenter, open-label, randomized, controlled, superiority trial. A total of 1300 eligible patients will be randomly allocated to undergo coronary angiography and/or percutaneous coronary intervention (PCI) through DRA or TRA using the 6 Fr Glidesheath Slender sheath introducer. Extended experience with both TRA and DRA is required for operators' eligibility and optimal evidence-based best practice to reduce RAO systematically implemented by protocol. The primary endpoint is the incidence of forearm RAO assessed by vascular ultrasound at discharge. Several important secondary endpoints will also be assessed, including access-site cross-over, hemostasis time, and access-site related complications. SUMMARY: The DISCO RADIAL trial will provide the first large-scale multicenter randomized evidence comparing DRA to TRA in patients scheduled for coronary angiography or PCI with respect to the incidence of RAO at discharge.

Serial optical frequency domain imaging in STEMI patients: the follow-up report of TROFI study.

AIMS: To investigate the incidence of incomplete stent apposition and to explore the impact of the presence of thrombus and protruding plaque after stent implantation on neointima formation at follow-up in ST-segment elevation myocardial infarction (STEMI) patients with serial optical frequency domain imaging (OFDI) investigations. METHODS AND RESULTS: In a multi-centre study, 141 patients with ST elevation myocardial infarction <12 h from onset were randomized to either PPCI with thrombectomy (TB) using an Eliminate catheter (TB: n = 71) or without TB (non-TB: n = 70). OFDI after drug-eluting stenting was performed using TERUMO OFDI system. Per protocol, at follow-up 49 patients segments were reimaged. At post-procedure and follow-up, there were no differences in stent and lumen areas between the two groups. At follow-up, per strut-level analysis, percentage of incompletely apposed struts was 0.42 ± 0.94 vs. 0.38 ± 0.77% (P = 0.76), and percentage of covered struts was 92.7 ± 7.2 vs. 94.4 ± 9.2% (P = 0.47) in the TB and non-TB groups, respectively. There was a positive correlation between intra-stent structure (ISS) volume at post-procedure and the neointima volume at 6-month follow-up (Pearson's r = 0.409, P = 0.04). Up to 12 months, there have been two and four patients having target vessel failure in the TB and in the non-TB groups, respectively. CONCLUSIONS: In patients with STEMI, there were no significant differences in OFDI parameters between TB and non-TB groups at both post-procedure and 6-month follow-up. However, ISS volume at post-procedure was positively associated with neointimal volume at 6-month follow-up.

Randomized study to assess the effect of thrombus aspiration on flow area in patients with ST-elevation myocardial infarction: an optical frequency domain imaging study--TROFI trial.

AIMS: Primary percutaneous coronary intervention (PPCI) with thrombectomy (TB) seems to reduce the thrombus burden, resulting in a larger flow area as measured with optical frequency domain imaging (OFDI). METHODS AND RESULTS: In a multi-centre study, 141 patients with ST elevation myocardial infarction <12 h from onset were randomized to either PPCI with TB using an Eliminate catheter (TB: n = 71) or without TB (non-TB: n = 70), having operators blinded for the OFDI results. The primary endpoint was minimum flow area (MinFA) post-procedure assessed by OFDI, defined as: [stent area + incomplete stent apposition (ISA) area] - (intraluminal defect + tissue prolapse area). Sample size was based on the expected difference of 0.72 mm(2) in MinFA. Baseline demographics, pre-procedural quantitative coronary angiography (QCA), and procedural characteristics were well matched between the two groups. On OFDI, the stent area (TB: 7.62 ± 2.23 mm(2), non-TB: 7.05 ± 2.12 mm(2), P = 0.14) and MinFA (TB: 7.08 ± 2.14 mm(2) vs. non-TB: 6.51 ± 1.99 mm(2), Δ0.57 mm(2), P = 0.12) were not different. In addition, the amount of protrusion, intraluminal defect, and ISA area were similar in the both groups. CONCLUSION: PPCI with TB was associated with a similar flow area as well as stent area to PPCI without TB.

MISAGO 1: first-in-man clinical trial with Misago nitinol stent.

AIMS: To evaluate a newly developed self-expanding Misago (Terumo Corp., Tokyo, Japan) nitinol stent with rapid exchange delivery catheter for the treatment of stenotic or occluded superficial femoral (SF) or popliteal arteries. METHODS AND RESULTS: MISAGO 1 clinical trial enrolled 55 patients undergoing percutaneous intervention of totally occluded or stenotic lesions in SF or popliteal arteries treated with the implantation of 81 stents in five centres across Europe. Primary endpoint was restenosis rate at six months assessed by duplex sonography. Patients (67% male) were 68+/-9 years old, 60% were smokers and 31% had diabetes. Clinical symptoms of ischaemia were present in all patients. Average lesion length was 85+/-50 mm, 64% were totally occluded and 38% classified as TASC C or D. The technical success rate was 100% while the procedural success rate was 98.2% without death, MI, stroke, or major bleeding. At six months follow-up the restenosis rate was 8.5%. One patient (1.8%) died of bronchial carcinoma and two (3.6%) underwent target vessel revascularisation. Mean ankle brachial index improved from 0.70 at baseline to 0.95 at six months while walking capacity on treadmill test improved with an average of 147 m. Rutherford index at six months demonstrated improvement of 72%, without any patients having symptom deterioration. One case of stent fracture was observed. CONCLUSIONS: The results from this first-in-man study indicate good safety and short to medium term efficacy profile of the Misago nitinol stent.