Editorial Comment

‘‘Once Upon A Time There Was. . . Intracoronary Thrombolysis’’

Ashok Seth,* FRCP, DSc Honoris Causa, FSCAI

Chairman, Fortis Escorts Heart Institute, New Delhi, India

The case report by Agarwal et al. in this issue ofthe journal describes the use of intracoronary (IC)Alteplase to lyse a bulky thrombus in left main/proxi-mal circumflex in a patient with anterior myocardialinfarction (MI) taken up for primary percutaneouscoronary intervention (PCI).

For those of us practicing PCI since the ’80s, thisis ‘‘dejavu’’ when IC lytics was being promoted as avaluable therapy for acute MI. It brings back memo-ries of the first 41 patients of PCI for acute MIreported by Hartzler et al. in 1983 [1] of which 29were pretreated with intracoronary lytic therapy.Numerous publications during the ’80s and ’90s (bal-loon angioplasty era) tried to evaluate the benefit ofIC lytics on thrombus dissolution, vessel patency andflow, on prevention of ‘‘no flow’’ and reocclusion,during primary PCI, and also for abrupt vessel closurefollowing balloon PCI and for vein graft occlusions.Small studies also compared doses, benefits, risks andmethods of administration of various lytic agents[2,3].

With the onset of ‘‘stent era’’ in mid ’90s, theenthusiasm for IC lytics died down. This was alsocoupled with introduction of better antiplatelet agents(thienopyridines/IIb IIIa receptor antagonists) forAcute Coronary Syndromes (ACS). The ‘‘deviceera’’ also brought in enthusiasm for ‘‘mechanicalthrombusters’’ and ‘‘embolic protection devices’’—which was intuitively the ‘‘right way to do things’’for most interventional cardiologists. There was aproliferation of devices to suck, rinse, extract macer-ate, or disintegrate thrombus (TEC, Angiojet, ultra-sound acolysis, rinspiration, Thrombus extractioncatheter, etc.) and if the thrombus did embolizedownstream there were balloon occlusion or filterdevices to catch and retrieve it. Some of these wereable to establish their benefits in improving out-comes in randomized trials and became mainstreamtreatment strategy, while others fell on the waysidefor a variety of reasons.

So in 2011, with a variety of ‘‘tools’’ at our dis-posal, do we really need IC thrombolysis? What is therelevance of this case report?IC thrombus still remains one of the most dreaded

enemies for interventional cardiologists, and we haveto battle it increasingly now that PCI for MI as wellas early invasive therapy for ACS have become the‘‘standard of care.’’Small amount of thrombus, (usually layered)

responds well to IIb/IIIa receptor antagonists (infactthere are numerous case reports of ‘‘dethrombosis’’effects of intracoronary abciximab) and entrapmentbehind the stent. Any residual small thrombus willusually get ‘‘autolysed’’ over a period of time as briskantegrade flow in a vessel works as one of the ‘‘bestlytics.’’Moderate amounts of partially occlusive thrombus in

presence of TIMI III flow may also respond to eitherintravenous or intra coronary infusion IIb/IIIa antago-nists infusion and anticoagulation over a few days bypromoting autolysis. In such cases, when the patient isbrought back to cath laboratory a few days later, thevessel looks ‘‘cleaned up’’ for safer stent implantation.This strategy is often helpful for thrombus in diffuselydegenerated saphenous vein graft. However, most of uswould prefer to complete the procedure at the ‘‘samesitting’’ due to logistics. For this, thrombus aspirationcatheters (Pronto, Vascular Solutions Inc. Minneapolis;Export Catheter, Medtronic, Minnesota) are easy touse, inexpensive, universally available and of provenefficacy [4].In specific cases, there may be concern regarding

dislodgment of thrombus and downstream embolizationof the micro or macro vascular bed, which can be pre-vented by adjunctive use of distal ‘‘balloon occlusion’’or ‘‘filter devices.’’

Conflict of interest: Nothing to report.

*Correspondence to: Okhla Road, New Delhi110025, India.

E-mail: ashok.seth@fortishealthcare.com

Received 16 May 2011; Revision accepted 21 May 2011

DOI 10.1002/ccd.23247

Published online 20 June 2011 in Wiley Online Library

(wileyonlinelibrary.com).

' 2011 Wiley-Liss, Inc.

Catheterization and Cardiovascular Interventions 78:76–77 (2011)

The real problem is ‘‘large,’’ ‘‘bulky’’ occlusive/nonocclusive thrombus as seen in large or ectaticarteries, left mains, vein grafts or during acutestent thrombosis. Such a large load of thrombususually clears only via the powerful extraction ofAngiojet thrombectomy (Medrad Possis, PA). ButAngiojet thrombectomy has limitations—it is notuniversally available and has a learning curve andexpense. In this case reported by Agarwal et al.,Angiojet thrombectomy would have worked admir-ably but I guess was not available. This is per-haps where IC lytics fits into the ‘‘action plan’’in the present era: i.e. for large bulky thrombusin large vessels or at dangerous sites like leftmain, threatening embolization with disastrous con-sequences, or embolized bulky thrombus in distalvessels not approachable by extraction or Angiojetthrombectomy catheters. IC lytics must be com-bined with judicious modification of anticoagulationand antiplatelet regimens to avoid periproceduralbleeding complications.

IC thrombolysis may be a ‘‘Once Upon a Time. . .. . .. . .’’ story, but still it is good to know and tell.You never know when you need it!

REFERENCES

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McCallister BD, Gura GM Jr, Conn RC, Crockett JE. Percutane-

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lytic therapy for treatment of acute myocardial infarction. Am

Heart J 1983;106(5 Pt 1):965–973.

2. Tennant SN, Dixon J, Venable TC, Page HL Jr, Roach A, Kaiser

AB, Frederiksen R, Tacogue L, Kaplan P, Babu NS. Intracoro-

nary thrombolysis in patients with acute myocardial infarction:

Comparison of the efficacy of urokinase with streptokinase. Cir-

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3. Tzefenbrunn A. Intracoronary thrombolysis. Chest 1992;101:1484–

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4. Svilaas T, Vlaar PJ, van der Horst IC, Diercks GF, de Smet BJ,

van den Heuvel AF, Anthonio RL, Jessurun GA, Tan E-S, Suur-

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Catheterization and Cardiovascular Interventions DOI 10.1002/ccd.Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).

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