premature occlusion of the coronary artery stents

Q: All of the following are the risk factors for the premature occlusion of the coronary artery stents except?

A) Premature cessation of dual anti-platelet therapy 
B) Smaller stent length 
C) Smaller vessel caliber
D) Left ventricular dysfunction 
E) Nonionic contrast media


Answer:  B

Premature cessation of dual anti-platelet therapy is the most common and the well known cause for the premature occlusion of the coronary artery stents but there is a long laundry list for this potentially life-threatening complication including proximal left anterior descending (LAD) stenting, side-branch stenting, diabetes mellitus, end-stage renal disease (ESRD), greater stent length, smaller vessel caliber, left ventricular dysfunction, use of nonionic contrast media, cocaine use, emergent stent placement, no aspirin at the time of the procedure, malignancy, multivessel disease.


References: 

1. Daemen J, Wenaweser P, Tsuchida K, et al. Early and late coronary stent thrombosis of sirolimus-eluting and paclitaxel-eluting stents in routine clinical practice: data from a large two-institutional cohort study. Lancet 2007; 369:667. 

2. Lagerqvist B, Carlsson J, Fröbert O, et al. Stent thrombosis in Sweden: a report from the Swedish Coronary Angiography and Angioplasty Registry. Circ Cardiovasc Interv 2009; 2:401. 

3.  Schühlen H, Kastrati A, Pache J, et al. Incidence of thrombotic occlusion and major adverse cardiac events between two and four weeks after coronary stent placement: analysis of 5,678 patients with a four-week ticlopidine regimen. J Am Coll Cardiol 2001; 37:2066. 

4. Scheller B, Hennen B, Pohl A, et al. Acute and subacute stent occlusion; risk-reduction by ionic contrast media. Eur Heart J 2001; 22:385.