Time for contrast material to traverse the epicardial artery and the myocardium in ST-segment elevation acute myocardial infarction versus unstable angina pectoris/non-ST-elevation acute myocardial infarction.

Although the time for contrast material to fill the epicardial artery in the setting of acute coronary syndromes has been studied extensively, the time for contrast material to fill the myocardium has not been evaluated. We compared differences in myocardial contrast material transit among patients with unstable angina pectoris/non-ST-elevation acute myocardial infarction (UAP/NSTEAMI) with patients with ST-elevation acute myocardial infarction (STEAMI). The time it took for contrast material to first appear and to arrive at peak intensity in the myocardium was compared in 224 patients with STEAMI enrolled in the LIMIT-AMI study versus 430 patients with UAP/NSTEAMI enrolled in the TACTICS-TIMI 18 trial. In patients with STEAMI, there was a delay in both the time for contrast material to first enter the myocardium (5,619 +/- 1,789 vs 4,663 +/- 1,626 ms, p <0.0001) and the time from entrance to peak blush intensity (2,387 +/- 1,359 vs 1,959 +/- 1,244 ms, p = 0.003) compared with patients with UAP/NSTEAMI. STEAMI remained significantly associated with impaired entrance of contrast material into the myocardium (p <0.0001) in a multivariate model controlling for known correlates of impaired epicardial flow (presence of thrombus, percent diameter stenosis, left anterior descending artery location, and contrast material inflow in the epicardial artery [corrected TIMI frame count]). The time for contrast material to enter the myocardium is impaired to a greater degree in STEAMI compared with UAP/NSTEAMI, even after adjusting for other variables known to delay flow in the epicardial artery. These data provide insight into potential mechanistic differences between these 2 clinical syndromes.

Effectiveness of rheolytic coronary thrombectomy with the AngioJet catheter.

Thrombus-filled lesions are associated with a higher rate of acute complications and long-term restenosis following conventional coronary or saphenous vein graft (SVG) intervention. To evaluate the clinical effectiveness of rheolytic thrombectomy in a nonselected population in the glycoprotein IIb/IIIa blockade era, we reviewed clinical, angiographic, and procedural data on 119 patients who underwent 126 consecutive coronary AngioJet procedures (29% in SVGs, and 71% in native coronary arteries) from July 1998 to August 2000. Glycoprotein IIb/IIIa blockers were used in 88%. Most vessels (68% of SVGs, 74% of native coronary arteries) were occluded initially. Complete or substantial removal of filling defects was achieved in 76% of SVGs and 66% of native coronary cases. The AngioJet rheolytic thrombectomy device led to significant improvement in lumen diameter and Thrombolysis In Myocardial Infarction (TIMI) flow, with reduction in the thrombotic lesion length (p <0.05). Angiographic success (<30% residual stenosis, TIMI-3) was attained in 73% of SVGs and 87% of native coronary procedures. Distal embolization occurred in 13 cases, and was less likely to occur in patients treated with abciximab (0%) compared with patients treated with other glycoprotein IIb/IIIa blockers or heparin alone (17%, p = 0.02). A favorable response to the AngioJet (odds ratio 3.9) and freedom from embolization (odds ratio 14.6) were associated with a higher procedural success rate. In-hospital and long-term clinical outcomes were favorable. Thus, rheolytic thrombectomy resulted in significant reduction of the thrombus burden in most patients, restored TIMI-3 flow, and led to favorable short- and long-term outcomes.

Rheolytic thrombectomy and platelet glycoprotein IIb/IIIa blockade for stent thrombosis.

Conventional transcatheter-based strategies result in good procedural success but poor clinical outcome in the treatment of intracoronary stent thrombosis. A combined approach of mechanical thrombus burden reduction using AngioJet rheolytic thrombectomy with adjunctive glycoprotein (GP) IIb/IIIa antagonists has not been studied. Between July 1998 and August 2000, 15 patients (17 procedures) underwent AngioJet thrombectomy for stent thrombosis at the Beth Israel Deaconess Medical Center. Patients were followed clinically through 6 months following the AngioJet procedure. All patients presented with signs of acute myocardial infarction at a median of 6 days following the original stenting procedure. Most vessels (88%) were occluded at presentation. A GP IIb/IIIa inhibitor was administered during 16 of the 17 procedures. Rheolytic thrombectomy resulted in complete removal of filling defects in all reviewed cases and led to significant improvement in lumen diameter and TIMI flow with reduction in the thrombotic lesion length (all P values < 0.05). Angiographic success (< 30% residual stenosis, TIMI 3 flow) was attained in all but one procedure. No patient required emergent coronary bypass grafting, repeat coronary angioplasty, or died in-hospital. At 6 months, there were no deaths and repeat revascularization was performed in four patients (29%). A combined approach of rheolytic thrombectomy with adjunctive GP IIb/IIIa blockade was highly effective in resolving stent thrombosis and was associated with favorable acute and long-term outcomes.