Background The incidence and correlates of postinterventional cardiac tropo
nin T (cTnT) elevation have not been evaluated in patients with successful
directional atherectomy (DCA). Methods Total creatine kinase (CK) activity,
CK-MB mass concentrations and cTnT levels were measured in 36 patients bef
ore, and serially 4, 24, 48 and 72 hours after successful DCA. Patients wer
e followed for death, Q-wave infarction, need for emergency bypass surgery
periprocedural vascular complications (transient in-lab vessel closure, sid
e branch compromise, large dissection), and non-Q-wave infarction on EGG. P
atients were followed for clinical outcomes and angiographic restenosis for
6 months. Vascular correlates were studied by coronary angiography and int
ravascular ultrasound before, immediately after and 4 hours after elective
and successful DCA. Results 25 patients (69.4%) had elevated levels of cTnT
, whereas CK-MB mass greater than or equal to 6 ng/ml and mild elevations o
f total CK activity were present in only 36.1 and 5.6%, respectively. Eleva
ted cTnT was related to vascular complications in 44% of cases. Inapparent
microembolization of platelets or plaque debris was considered responsible
for most of the remaining microne-croses. During 6 month follow-up rates of
clinical restenosis (44 vs 9%, p = 0.059) tended to be higher in patients
with as compared to patients without CTnT release after DCA. Conclusion Suc
cessful DCA is associated with postprocedural elevations of cTnT which rela
te to minor vascular complications and presumably microembolization of plat
elets or plaque debris. The superior diagnostic performance of cTnT compare
d to CK-MB mass may relate to more sensitive identification of microinfarct
ion. Further studies are mandatory to confirm the association between eleva
tion of cTnT and risk of restenosis and TVR.