Author Affiliations: From the Department of Cardiology, Gazi University School of Medicine, Ankara, Turkey. The authors report no conflicts of interest regarding the content herein. Manuscript submitted March 10, 2008, provisional acceptance given April 24, 2008, manuscript accepted May 27, 2008. Address for correspondence: Sedat Turkoglu, MD, Gazi University School of Medicine, Department of Cardiology, 06500, Besevler, Ankara, Turkey. Email: firstname.lastname@example.org
ABSTRACT: A 50-year-old male with a history of inferior myocardial infarction and stent implantation to the right coronary artery 20 days prior this admission presented with acute inferior myocardial re-infarction. Diagnostic right coronary angiography revealed a massive thrombus within the previously implanted stent. After manual aspiration through a guiding catheter, a large, fresh thrombus was removed. Subsequently, thrombolysis in myocardial infarction (TIMI) 3 flow was established, and no further intervention was required. The patient was discharged uneventfully on medical therapy.
J INVASIVE CARDIOL 2008;20:E304–E305
After optimal stent implantation and appropriate use of antiplatelet therapy, subacute stent thrombosis is a rare event. However, when it occurs, morbidity and mortality rates are high. We describe a patient who presented with subacute stent thrombosis after discontinuing antiplatelet drugs. We treated this patient with transcatheter thrombus aspiration using a standard guiding catheter. To date, there is no report of transcatheter thrombus aspiration using a standard guiding catheter in the treatment of subacute stent thrombosis.
Case Report. A 50-year-old male was admitted to the emergency room with complaints of retrosternal chest pain and dizziness lasting for 7 hours. In another hospital, he underwent primary coronary angioplasty and stent implantation to the proximal and middle segments of the right coronary artery (RCA) during an acute inferior myocardial infarction 20 days prior to this admission. He was discharged on clopidogrel 75 mg/day and aspirin 100 mg/day, with which he did not comply. Physical examination revealed a pulse of 45/minute and a blood pressure of 90/60 mmHg. Electrocardiography showed sinus bradycardia and ST-segment elevation in the inferior leads. Aspirin and 4,000 IU of unfractionated heparin were started, and he was taken to the catheterization laboratory immediately for primary coronary intervention. Selective coronary angiography revealed normal left anterior descending and circumflex arteries and stent thrombosis in the right coronary artery, with thrombolysis in myocardial infarction (TIMI) grade 0 flow (Figure 1). After engaging the right coronary ostium, we passed a guidewire through the total occlusion and observed a large thrombus burden with a TIMI grade 1 flow (Figure 2). We gently advanced the 6 Fr Judkins right guiding catheter (deep intubation) until its tip was in close proximity to the thrombus in the stent. Then, we connected a 20 cc syringe to the proximal end of the catheter and aspirated manually. In the first aspiration, we obtained a fresh, large thrombus measuring 22 mm in length (Figure 3). We aspirated 3 more times to ensure that there was no aspirate left in the guiding catheter, which could have led to distal embolization.After this procedure, we performed a coronary injection and saw that a TIMI grade 3 flow was established with a small residual thrombus, which did not impede coronary blood flow (Figure 4).Tirofiban infusion was then started, and the patient was transferred to the coronary care unit. A control coronary angiogram was performed 24 hours after the patient’s presentation, revealing TIMI 3 flow with no deterioration in coronary blood flow and resolution of the remaining thrombus (Figure 5). The patient was followed up for 7 days and was discharged on medical therapy including aspirin, clopidogrel and a beta-blocker.
Discussion. Stent thrombosis is one of the most feared complications of percutaneous intervention. Although the incidence of subacute thrombosis decreased as a result of optimal stent implantation and the use of antiplatelet regimens including both aspirin and a thienopyridine,1,2 it still occurs with an incidence of about 1%.3 In our case, the most probable cause of the stent thrombosis was the noncompliance with the prescribed dual antiplatelet regimen.
The usual treatment for stent thrombosis is emergency percutaneous intervention.4 If balloon dilatation does not suffice, stents can be useful. Even with this therapy, the mortality rate of stent thrombosis may be as high as 6.7% at 30 days3 or 11% at 6 months.4 However, one study has shown that the addition of mechanical thrombectomy to percutaneous intervention resulted in a high procedural success rate, with a zero 30-day mortality rate.5 Based on this favorable result and the unavailability of a thrombectomy system at our laboratory, we decided to aspirate the thrombus with a standard guiding catheter. After aspirating a huge thrombus, TIMI 3 flow was achieved and no further intervention was needed.
To our knowledge, this is the first case of thrombus aspiration through a standard guiding catheter for stent thrombosis of a coronary artery. Due to the successful results in this case, we conclude that aspiration through a guiding catheter may be an option for the treatment of stent thrombosis.