Abnormal Coronary Flow Velocity Reserve After Coronary Intervention Is Associated With Cardiac Marker Elevation

Abstract

Background-Residual reduction of relative coronary flow velocity reserve (rCVR) after successful coronary intervention has been related to microvascular impairment. However, the incidence of cardiac enzyme elevation as a surrogate marker of an underlying embolic myocardial injury in these cases has not been studied. Methods and Results-A series of 55 consecutive patients with successful coronary stenting, periprocedural intracoronary Doppler analysis, and determination of creatine kinase (CK; upper limit of normal [ULN] for women 70 IU/L, for men 80 IU/L) and cardiac troponin T (cTnT; bedside test, threshold 0.1 ng/mL) before and 6, 12, and 24 hours after intervention were studied. Postprocedural rCVR was the only intracoronary Doppler parameter that independently correlated with cTnT (rϭϪ0.498, PϽ0.001) and CK outcome (rϭϪ0.406, Pϭ0.002). Receiver operating characteristic analysis identified a postprocedural rCVR of 0.78 as the best discriminating value, with a sensitivity of 83.3% and 69.2% and a specificity of 79.1% and 76.2% for detection of cTnT and CK elevation, respectively. Stratified according to this cutoff value, the incidence of cTnT elevation was 52.6% in patients with (nϭ19) and 5.6% in patients without (nϭ36) a postprocedural rCVR Ͻ0.78 (PϽ0.001), associated with a CK elevation Ͼ1 times the ULN in 36.8% and 5.6% (Pϭ0.005) of patients, respectively. Conclusions-Cardiac marker elevation can frequently be found after coronary procedures that are associated with a persistent reduction of rCVR, indicating procedural embolization of atherothrombotic debris with microvascular impairment and myocardial injury as a potential underlying mechanism.

Preprocedural Statin Medication Reduces the Extent of Periprocedural Non–Q-Wave Myocardial Infarction

“…7,8 All patients received either ticlopidine (500 mg/d) or clopidogrel (75 mg/d, 300 mg as loading dose) for 4 weeks in addition to continued aspirin medication (100 mg/d).…”

“…Cardiac serum markers were analyzed as described previously. 8 Determination of CK-MB serum activity was made available in case of CK elevation.…”

Pathophysiological aspects and management workflow of coronary microvascular obstruction in ST-segment elevation myocardial infarction

“…Recently, a pre-existing impairment of the myocardial microcirculation, principally due to cardiovascular risk factors, has been shown to yield greater vulnerability to PCIrelated myocardial injury as well as a poor long-term outcome. 5,6 In particular, a pre-existing transient or permanent microcirculatory dysfunction may con-N o n -c o m m e r c i a l u s e o n l y tribute to the development and prognosis of acute coronary syndrome (ACS) via reduction of coronary blood flow, leading to an alteration of shear stress and thereby worsening of endothelial function at epicardial level as well as aggravation of thrombus formation. 7 Ischemic and reperfusion related injuries have been translated to humans from the animal models with a first description by Kloner et al 8 In particular, electron microscopic analysis after 90-min coronary occlusion followed by reperfusion, revealed severe capillary damage, endothelial protrusions and blebs blocking the capillary lumen, and endothelial gaps with extra vascular erythrocytes.…”

Detection of Coronary Microembolization by Doppler Ultrasound in Patients With Stable Angina Pectoris Undergoing Elective Percutaneous Coronary Interventions

“…1 The occurrence of coronary microembolism can be assumed when coronary flow velocity reserve (CFVR) remains impaired and periprocedural cardiac markers are elevated. 2 Patients who experience no normalization of postprocedural CFVR after coronary microembolization also typically have an increase in basal average peak velocity. 3,4 Experimentally, a progressive contractile dysfunction developed in response to coronary microembolization over a period of hours; it was not associated with reduced regional myocardial blood flow (perfusion-contraction mismatch) but rather with a local inflammatory reaction.…”