Temporary scaffolding of coronary arteries with bioabsorbable magnesium stents: a prospective, non-randomised multicentre trial.
BACKGROUND
Coronary stents improve immediate and late results of balloon angioplasty by tacking up dissections and preventing wall recoil. These goals are achieved within weeks after angioplasty, but with current technology stents permanently remain in the artery, with many limitations including the need for long-term antiplatelet treatment to avoid thrombosis. We report a prospective multicentre clinical trial of coronary implantations of absorbable magnesium stents.


METHODS
We enrolled 63 patients (44 men; mean age 61.3 [SD 9.5 years]) in eight centres with single de novo lesions in a native coronary artery in a multicentre, non-randomised prospective study. Follow-up included coronary angiography and intravascular ultrasound at 4 months and clinical assessment at 6 months and 12 months. The primary endpoint was cardiac death, non-fatal myocardial infarction, or clinically driven target lesion revascularisation at 4 months


RESULTS
71 stents, 10-15 mm in length and 3.0-3.5 mm in diameter, were successfully implanted after pre-dilatation in 63 patients. Diameter stenosis was reduced from 61.5 (SD 13.1%) to 12.6 (5.6%) with an acute gain of 1.41 mm (0.46 mm) and in-stent late loss of 1.08 mm (0.49 mm). The ischaemia-driven target lesion revascularisation rate was 23.8% after 4 months, and the overall target lesion revascularisation rate was 45% after 1 year. No myocardial infarction, subacute or late thrombosis, or death occurred. Angiography at 4 months showed an increased diameter stenosis of 48.4 (17.0%). After serial intravascular ultrasound examinations, only small remnants of the original struts were visible, well embedded into the intima. Neointimal growth and negative remodelling were the main operating mechanisms of restenosis.


CONCLUSIONS
This study shows that biodegradable magnesium stents can achieve an immediate angiographic result similar to the result of other metal stents and can be safely degraded after 4 months. Modifications of stent characteristics with prolonged degradation and drug elution are currently in development.
Erbel
Raimund
R
West-German Heart Center Essen, Department of Cardiology, Essen, Germany. Electronic address: erbel@uk-essen.de.
Di Mario
Carlo
C
Royal Brompton Hospital, Imperial College London, London, UK.
Bartunek
Jozef
J
Cardiovascular Centre, OLV Ziekenhuis, Aalst, Belgium.
Bonnier
Johann
J
Department of Cardiology, Catharina Hospital, Eindhoven, Netherlands.
de Bruyne
Bernard
B
Cardiovascular Centre, OLV Ziekenhuis, Aalst, Belgium.
Eberli
Franz R
FR
Department of Cardiology, University Hospital Zurich, Zurich, Switzerland.
Erne
Paul
P
Cardiology Department, Kantonal Hospital, Lucerne, Switzerland.
Haude
Michael
M
West-German Heart Center Essen, Department of Cardiology, Essen, Germany.
Heublein
Bernd
B
Hannover Medical School, Leibniz Laboratory for Biotechnology and Artificial Organs, Hannover, Germany.
Horrigan
Mark
M
Cardiology Department, Austin and Repatriation Medical Centre, Victoria, Melbourne, Australia.
Ilsley
Charles
C
Harefield Hospital, Imperial College London, London, UK.
Böse
Dirk
D
West-German Heart Center Essen, Department of Cardiology, Essen, Germany.
Koolen
Jacques
J
Department of Cardiology, Catharina Hospital, Eindhoven, Netherlands.
Lüscher
Thomas F
TF
Department of Cardiology, University Hospital Zurich, Zurich, Switzerland.
Weissman
Neil
N
Washington Hospital Center, Washington DC, USA.
Waksman
Ron
R
Washington Hospital Center, Washington DC, USA.
D020341:Absorbable Implants; D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000628:therapy*; D003328:Coronary Thrombosis / Q000517:prevention & control; D023381:Endpoint Determination / Q000379:methods; D004867:Equipment Design; D005260:Female; D006801:Humans; D007902:Length of Stay; D008274:Magnesium; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015607:Stents; D014463:Ultrasonography
D008274:Magnesium