6 months Evaluation of the BIOTRONIK CoCr PRO-Kinetic Coronary Stent System in patients with single de Novo lesions in Native Coronary Arteries

Stenting has become the dominant percutaneous coronary intervention.The main
benefit of stenting compared with percutaneous coronary balloon angioplasty
consists in a significant reduction in the rate of restenosis and thus of
repeated interventions. Ongoing changes in the stent design have improved the
procedural success rate and short-term lumen gain. Different stent designs have
different impact on restenosis as demonstrated by a number of performed
studies.
Much efforts and resources are concentrated on strategies aiming at the
prevention of in-stent restenosis. The identification of stent properties that
reduce lumen renarrowing may offer a simple, cost-effective, and readily
available option against restenosis.
An important issue in stent design is the thickness of stent struts.
Angiographic results of different trails showed that strut thickness affects
the results of restenosis. The ISAR-STEREO trial compared two stents with
similar design but a different strut thickness. One year after stenting,
patients who received stents with thinner struts had a considerably lower
restenosis rate than those receiving thicker-strut stents. The magnitude of
difference in restenosis in the ISAR-STEREO (42% risk reduction with the
thin-strut stent) suggests that strut thickness plays a major role in this
process, with relevant implications for stent technology.
The ISAR-STEREO-2 trial compared two stents with different design and different
strut thickness. The incidence of angiographic restenosis was 17.9% in the
thin-strut group and 31.4% in the thick-strut group. (P<0,001). The TVR due to
restenosis was required in 12.3% of the thin-strut group and 21.9% of the thick
strut group (P=0,002). When two stents with different design are compared, the
stent with thinner struts elicits less angiographic and clinical restenosis
than the thicker-strut stent.
Cobalt-chromium stents emerged only recently but are progressively replacing
conventional stents made of 316 L stainless steel. Cobalt-chromium has the
advantage of being stronger than 316 L stainless steel allowing for
construction of stents with thinner struts without compromising radial
strength. Furthermore, the presence in the alloy of W-atoms with a high ordinal
number gives cobalt-chromium stents sufficient radiopacity even with thinner
struts. In addition, cobalt-chromium may confer an advantage in thrombosis
safety and create less artifacts during MRI examinations than stainless steel.
The Pro-Kinetic coronary stent is covered with a passive coating named PROBIO.
PROBIO coating has also been shown to reduce the factors that contribute to
restenosis, such as protein activation, platelet activation and
endothelialisation. In-vitro data demonstrate a reduction in the proliferation
of smooth muscle cells on silicon carbide coated stents by up to 52% when
compared to stainless steel stents.
An indication for stenting using the BIOTRONIK PRO-Kinetic BMS platform will
only be sought if the BIOTRONIK PRO-Kinetic BMS platform is determined to be
non-inferior to the Multi-Link Vision stent from Guidant. Effectiveness and
safety of the BIOTRONIK PRO-Kinetic BMS platform for stenting coronary lesions
will be determined by Target Vessel Failure (TVF) 6 months after implantation.
Non-inferiority to the Guidant Multi-Link Vision Registry Target Vessel Failure
using the Multi-Link Vision stent will support the BIOTRONIK labeling for
stenting coronary lesions.

The primary objective of this study is to evaluate safety and efficacy of the
BIOTRONIK PRO-Kinetic coronary CoCr-stent in patients with single de novo
lesions of native coronary arteries.

The PRO-Kinetic study is a multi-center, prospective, consecutive
non-randomized study enrolling 200 patients with single and multiple de novo
lesions in native coronary arteries who meet entry criteria. Those who provide
informed consent will be enrolled to receive the PRO-Kinetic stent. Telephone
follow-up will be performed at 1 month for all enrolled patients. After 6
months 100 patients will have an angiographic follow-up and 100 patients will
be checked by telephone again. After 12 months a telephone follow-up will be
performed for all enrolled patients.
Patients who underwent treatment of non-target lesions less than 30 days prior
to the index procedure, should not be enrolled in this trial.

All patients will receive the PRO-Kinetic stent

Benefits:
Percutaneous transluminal coronary angioplasty (PTCA) has been widely used as
an alternative to medical or surgical treatment in patients with symptomatic
coronary artery disease. The principal limitations of PTCA (abrupt closure,
intimal dissection, and restenosis) are solved by implantation of coronary
stents. The PRO-Kinetic stent system is developed to provide an optimal luminal
diameter and maintain arterial patency during and after percutaneous coronary
interventions.


Risks related to the implantation of the PRO-Kinetic stent system are supposed
to be the same as those associated with other percutaneous treatment procedures
for a diseased coronary artery using any other bare metal stent.
The following complications, also related to standard PTCA, coronary
angiography, and coronary stenting, could happen:
• Death
• Access site (femoral, radial or brachial) aneurysm, pseudoaneurysm, or
arteriovenous fistula
• Requirement for emergency coronary artery bypass graft (CABG)
• Stroke / transient ischemic attack
• Cardiac tamponade
• Dissection, perforation, or rupture of the coronary artery
• Embolism (air, tissue, device [stent], or thrombus)
• Stent thrombosis
• Early or late stent occlusion
• Total occlusion of the artery
• Acute myocardial infarction
• Restenosis of the stented artery
• Arrhythmias
• Hemorrhage, possibly requiring transfusion
• Renal insufficiency
• Respiratory failure
• Shock / pulmonary edema
• Abrupt vessel closure or spasm
• Hypertension / hypotension
• Allergic reaction (to contrast media, antiplatelet therapy, stent material)
• Peripheral ischemia / peripheral nerve injury
• Infection or fever
• Unstable angina, myocardial ischemia
• Pain at catheter insertion site
• Balloon rupture
• Failure to deliver the stent to the intended site of the vessel
• Incomplete stent apposition
• Stent compression
• Hematoma
The occurrence of the complications listed above could lead to the necessity of
a repeat percutaneous coronary intervention, or to a myocardial infarction, an
emergency coronary artery bypass graft, or even to death. The PRO-Kinetic is a
CE approved coronary stent system, so the risks should be similar to those
associated with the implantation of any other bare metal stent.