Overcoming the Final Challenge in STEMI PCI: Reducing Infarct Size with Super-Selective ClearWay Catheter-Directed Delivery of Abciximab with Aspiration Thrombectomy

Case Report

A 49-year-old gentleman with history of hyperlipidemia presented to the emergency room with two hours of chest pain. His EKG demonstrated anterior wall ST-elevation myocardial infarction (STEMI). He was given aspirin 325 mg, prasugrel 60 mg and was taken emergently to the cardiac catheterization laboratory for primary percutaneous coronary intervention (PCI). Upon diagnostic angiography, the patient was found to have a total occlusion of the left anterior descending coronary artery (LAD) (Figure 1). The remainder of coronary arteries, the left main, circumflex and right coronary arteries, were without significant stenosis. The patient was given 60 units/kg unfractionated heparin.

The LAD was successfully navigated with a 0.014-inch guide wire without difficulty. A 1.0 mm x 10 mm ClearWay (Atrium Medical) therapeutic infusion catheter was positioned inside the occlusion and a weight-based (0.25 mg/kg) abciximab bolus dose was delivered (Figure 2). Subsequently, aspiration thrombectomy was performed with the XpressWay aspiration catheter (Atrium Medical). Angiography revealed a patent LAD with severe stenosis (Figure 3). A 3.5 mm x 18 mm Xience V (Abbott) drug-eluting stent was deployed. Angiography showed TIMI grade 3 and a myocardial blush grade of 3 (Figures 4-5). The procedure was concluded and the patient was sent to the telemetry unit for recovery. During the post procedure period, no heparin or abciximab infusions were given. The patient was started on a daily dose of aspirin 81 mg and prasugrel 10 mg. The patient’s peak CPK during hospitalization was only 543 and troponin was 1.95. He had an uneventful course during hospitalization and was discharged. The patient was seen in follow-up 30 days later without any symptoms. He returned to normal duty. At 30 days, his transthoracic echocardiogram revealed an ejection fraction of 50% without any wall motion abnormality.

Discussion

In every cath lab in America, there is a bulletin board with charts tracking door-to-device times. Saving heart muscle by reducing infarct size is the ‘holy grail’, and remains one of the last remaining challenges of PCI. We haven’t seen this endpoint achieved in a multicenter, randomized, prospective trial since the thrombolysis trials conducted in the 1990’s, and it came at the price of increased bleeding with lytic therapy. In the INFUSE-AMI trial, a bolus-only strategy of abciximab through the ClearWay catheter preserved heart muscle compared to standard PCI (balloon and stent), without increasing the risk of bleeding. 

We know from previous studies that time of onset to intervention is correlated to degree of heart muscle saved, thus leading to smaller extent of myocardial injury.¹ Post hoc analysis of the INFUSE-AMI trial showed the combination of manual extraction catheter and intra-coronary selective, bolus-only abciximab delivered via the ClearWay drug delivery balloon saved the most heart muscle. This reduction is remarkable when one realizes that the average onset of chest pain to presentation for patients enrolled in the trial was 99 minutes. The previously published ATTEMPT meta-analysis² suggested a “synergistic relationship” between manual extraction and abciximab, with the largest reduction in mortality when both therapies were utilized. It is crucial to note that use of the ClearWay therapeutic drug delivery balloon was utilized rather than a simple guide injection of abciximab. The guide catheter delivery of abciximab did not show any difference in the AIDA STEMI (Abciximab i.v. Versus i.c. in ST-elevation Myocardial Infarction) trial.³ Use of the ClearWay atraumatic balloon increases drug contact with thrombus, increasing concentration and residence time, which leads to a greater reduction in TIMI thrombus burden score⁴, a hallmark of this therapy.

The INFUSE-AMI trial reaffirmed our current treatment strategy for patients presenting with large clinical infarcts and a heavy thrombus burden. Protecting patients from emboli that may have dislodged during the initial plaque rupture and resolving residual thrombus that may remain behind after manual extraction can only be accomplished via local drug delivery. INFUSE-AMI confirms what we see in our own clinical experience of over 1,000 PCI cases — localized, bolus-only drug delivery is safe and effective in saving heart muscle, resulting in the best outcomes for our patients.

Dr. Dave can be contacted at rdintervention@yahoo.com

References

1. Penicka M, Horak J, Kobylka P, Pytlik R, et al. Intracoronary injection of autologous bone marrow-derived mononuclear cells in patients with large anterior acute myocardial infarction: a prematurely terminated randomized study.  J Am Coll Cardiol 2007;49: 2373-2374.
2. De Vita M, Burzotta F, Biondi-Zoccai GG, Lefevre T,  et al. Individual patient-data meta-analysis comparing clinical outcome in patients with ST-elevation myocardial infarction treated with percutaneous coronary intervention with or without prior thrombectomy. ATTEMPT study: a pooled Analysis of Trials on ThrombEctomy in acute Myocardial infarction based on individual Patient data. Vasc Health Risk Manag 2009;5(1):243-247. 
3. Thiele H, Wöhrle J, Hambrecht R, Rittger H, et al. Intracoronary versus intravenous bolus abciximab during primary percutaneous coronary intervention in patients with acute ST-elevation myocardial infarction: a randomised trial. Lancet 2012 Mar 10;379(9819):923-931. 
4. Capodanno D, Prati F, Pawlowsky T, Ramazzotti V, et al. ClearWayRX system to reduce intracoronary thrombus in patients with acute coronary syndromes according to optical coherence tomography after abciximab intracoronary local infusion trial (COCTAIL): study rationale and design. J Cardiovasc Med (Hagerstown) 2010 Feb;11(2):130-136.

Disclosure: Dr. Dave reports consultant, research and training honoraria from Atrium Medical, speaking honoraria from Lilly/Daichi Sankyo, and research, training and speaking honoraria from Abbott Vascular.