What to Do When Your Aspiration Thrombectomy Catheter Gets Overwhelmed

This article received double-blind peer review from members of the Cath Lab Digest Editorial Board.

Disclosures: The authors report no conflicts of interest regarding the content herein.

The authors can be contacted via Dr. Muhammad Khan at muhammad.khan@sanfordhealth.org.

Introduction

Percutaneous coronary intervention (PCI) in the setting of acute myocardial infarction can be complicated by distal embolization of thrombus/atherosclerotic debris with the resulting decreased flow known as the “no reflow” phenomenon. Aspiration thrombectomy can theoretically reduce the incidence of this complication and currently carries a class IIa recommendation from the American College of Cardiology/American Heart Association in the setting of acute myocardial infarction.¹ Numerous devices have been developed and are currently in use for aspiration thrombectomy. Results have been mixed regarding outcomes with the use of these devices, however, and their use still remains controversial. Incomplete thrombus clearance can be one reason for suboptimal results. Sometimes thrombus is too large to be evacuated through the catheter and becomes lodged inside, with a resulting lack of blood return while the aspiration syringe is on negative pressure.  

Case

A 53-year-old male presented to the emergency room with 5 hours of retrosternal pain with associated nausea. The patient was noted to be diaphoretic and ill appearing. He was hypotensive and bradycardic. An initial electrocardiogram revealed extensive inferior ST-elevation myocardial infarction (STEMI) with complete atrioventricular (AV) block. Emergent coronary angiography revealed a completely thrombotically occluded right coronary artery (RCA) (Figure 1). Due to a large thrombus burden, we opted to proceed with aspiration thrombectomy.  

Initially, an Export AP aspiration catheter (Medtronic) was used, but at attempt, the flow would stop in the aspiration syringe, in spite of maintained negative pressure. Thus, each time we would take the aspiration catheter out, we would find a large piece of thrombus stuck at the end of the device, completely blocking the flow (Figures 2-3). In cases of poor or no flow into an aspiration syringe in spite of negative pressure applied, we advise maintaining a vacuum (negative pressure inside of the thrombectomy catheter), as premature discontinuation of suction can lead to thrombus dislodgement back into the coronary circulation, aorta, or guide catheter. In such cases, negative pressure in the aspiration syringe should be maintained until the catheter is out of the body. Then it should be well flushed before it can be used again. If thrombus dislodges in the guide catheter while on the way out, a loss or dampening of catheter tip pressure can be seen. In such cases, after removing the aspiration catheter, the guide catheter should be aspirated vigorously (avoid injecting through the guide catheter until full blood return and normal pressure waves are restored). Sometimes, it is necessary to disconnect the guide from the Y connector, as even with aggressive suctioning, the thrombus cannot be cleared. 

Despite repeated aspirations with an Export AP catheter, poor RCA flow and a still-large thrombus burden was present (Figure 4). We completed the case successfully by “mega thrombectomy” using a GuideLiner catheter (Vascular Solutions). This technique involves advancement of the GuideLiner catheter into the coronary artery and aspiration syringe connected to the three-way stopcock. Suction is applied through the guide, with eventual thrombus aspiration through the tip of GuideLiner into the guide and then out to aspiration syringe.^2,3 The GuideLiner has a larger lumen than any aspiration catheter; thus, in our experience, it provides for more robust thrombus export. The GuideLiner needs to be advanced carefully into the coronary artery to avoid dissection or even perforation while aspirating. Aspiration can be continued also on withdrawal of the GuideLiner from the artery. Once the GuideLiner tip is back in the guide catheter and free backflow of blood is present, suction is stopped and pressure wave at catheter tip should be assessed. If normal back flow and pressure wave are present, then there should be no thrombus left in the GuideLiner/guide catheter, and it is safe to proceed with PCI. In our case, the GuideLiner method did not result in occlusion with thrombus in the GuideLiner, and a good final result was obtained (Figure 5). The patient did well post procedure and one month later, was doing well in cardiac rehab. 

References

1. American College of Emergency Physicians; Society for Cardiovascular Angiography and Interventions, O’Gara PT, et al. 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2013 Jan 29; 61(4): e78-140. doi: 10.1016/j.jacc.2012.11.019.
2. Stys AT, Stys TP, Rajpurohit N, Khan MA. A novel application of GuideLiner catheter for thrombectomy in acute myocardial infarction: a case series. J Invasive Cardiol. 2013 Nov; 25(11): 620-624.
3. Mani AJ. Novel use of a guide extension mother-and-child catheter for adjunctive thrombectomy during percutaneous coronary intervention for acute coronary syndromes. J Invasive Cardiol. 2014 Jun; 26(6): 249-254.