Summary
Subacute thrombosis (SAT) is a major concern in patients undergoing percutaneous coronary
intervention (PCI). So far, only little data has been available on characteristics
and outcome of patients with SAT after primary PCI for ST elevation myocardial infarction
(STEMI). From 1997–2001, 1,548 unselected consecutive patients underwent primary PCI
for STEMI as part ofa randomized controlled trial stenting vs. balloon angioplasty.
All patients received acetylsalicylic acid (500 mg i. v.) and heparin (5,000 IU) before
the procedure. After stenting, all patients received ticlopidine 250 mg daily (before
July 1999) or clopidogrel 75 mg daily (after July 1999) for one month. Five percent
of patients received glycoprotein IIb/IIIa blockers. We prospectively recorded incidence
and characteristics of patients with SAT during one year follow-up. SAT occurred in
4. 1% (63/1548) and reinfarction in 6. 0% of patients. The incidence of SAT did not
change over time (1997: 8/175[4. 6%],1998: 8/325 [2.5%],1999: 13/358 [3.6%], 2000:
22/426 [5.2%], 2001: 12/264 [4.5%]). SAT occurred in 39/63(62%) patients during hospital
stay. The incidence did not differ between patients after ticlopidine 23/681 (3.4%)
or clopidogrel 40/867 (4. 6%, p=0. 222). Univariate predictors of SAT were: patients
with an LAD stenosis (5.4% vs. 2.9%, p=0. 016), with Killip class>1 at presentation
(8.6% vs. 3.7%, p=0.007) and in patients who received a stent (5.1% vs. 2.7%, p=0.
022). After multivariate analysis, Killip class>1 on admission was the only independent
predictor of SAT(OR 2.26, 95% CI 1.14–4.47, p=0.019). SAT was associated with a higher
mortality at long-term follow-up (15% vs. 7%, p=0. 026). In a prospectively recorded,
unselected consecutive series of patients undergoing PCI for STEMI, SAT occurred in
4. 1% of patients at oneyear follow-up. Signs of heart failure on admission, anterior
myocardial infarction and stenting were predictors of SAT.
Keywords
Subacute thrombosis - catheterization - STEMI - prognosis - PCI
