Treatment of acute stent thrombosis with local urokinase therapy using catheter-based,drug delivery systems: A case report

Abrupt thrombotic stent closure remains a difficult problem to treat in the cardiac catheterization laboratory. A 63-yr-old white female initially underwent successful placement of a Palmaz-Schatz biliary stent in the proximal RCA following failed coronary angioplasty. One week later, the patient represented with an acute inferior infarction and thrombotic occlusion of the stent site in spite of adequate anticoagulation. A new, local drug infusion catheter (the Dispatch? catheter) was placed at the angioplasty site and 150,000 units of urokinase were locally infused, with immediate restoration of normal distal flow and a subsequent marked decrease in angiographic thrombus. A small, residual thrombotic filling defect was further treated with a urokinase-coated hydrogel balloon (Hydro Plus?). Following local urokinase delivery with the Dispatch catheter and hydrogel balloon, there was complete resolution of angiographic thrombus with TIMI 3 flow and no evidence of distal embolization or no-reflow. Local urokinase delivery directly to the site of thrombus with catheter-based drug delivery systems may be a useful technique for rapidly lysing intracoronary clot and re-establishing coronary flow in the setting of acute stent thrombosis.     

Treatment of a native right coronary artery with the PercuSurge Guardwire protection system during PTCA and stenting

Cardiac catheterization in a patient with recent-onset unstable angina demonstrated a suboccluded dominant right coronary artery (RCA), with angiographic evidence of a large thrombus load and a severe focal stenosis of the left anterior descending (LAD) coronary artery. After abciximab, uneventful PTCA and stenting of the LAD was performed. The thrombus containing lesion of RCA was treated with balloon predilatation and stent deployment, and the whole procedure was accomplished with protection of the distal vessel by means of PercuSurge. This device was planned to avoid distal debris migration during percutaneous interventions of saphenous bypass grafts. The system is designed to allow the placement of a temporary occlusion device, a low-profile balloon, distal to the lesion to be treated during the procedure. The occlusive balloon is kept inflated during the treatment of the lesion. Before deflating the balloon and allowing blood to reach the distal vessel, whenever it is necessary, the material proximal to the balloon is aspirated through a monorail catheter. This aspiration removes blood and thrombi proximal to the occlusive balloon from the treated coronary artery. The case we present first reports the application of the device in a large native coronary artery, with an optimal distal flow restoring and no evidence of thrombus embolization. This type of protection of distal coronary vessels towards micro- and macroembolization of thrombi is a promising system of performing safer percutaneous interventions, even in acute ischemic syndromes.     

Advantages of MGuard coronary stent system

Effectiveness of percutaneous coronary intervention (PCI) within thrombus containing lesions (ST-segment elevation myocardial infarction setting, degenerated saphenous venous grafts) is limited by the risk of occurrence of distal embolization and no-reflow phenomenon. Several pharmacological agents, as well as mechanical devices (i.e. manual aspiration catheters/mechanical thrombectomy, proximal and distal protection devices) were introduced, in the last years, to reduce the risk of angiographic complications during percutaneous coronary intervention and to improve myocardial reperfusion. Recently, the MGuard stent (Inspire MD, Tel Aviv, Israel), a bare-metal stent covered by micron level mesh, which allows to prevent distal embolization by blocking the atherothrombi prolapse through the stent struts during deployment has been introduced. This article discusses the data concerning safety and efficacy of mesh covered stent implantation in a ST-segment elevation myocardial infarction setting, as well as during percutaneous coronary intervention in saphenous venous grafts.     

Covered stent graft for primary PTCA of an aortocoronary vein graft

Covered stent graft by entrapping the thrombus between the vessel wall and stent might be helpful in preventing distal embolization and "no reflow" in a high-risk patient cohort. We here present a case with successful restoration of coronary flow in a highly thrombogenic milieu (acute myocardial infarction) with implantation of two covered stent grafts which by entrapping the thrombus avoided the distal embolization and "no reflow" in a totally occluded saphenous vein graft (SVG). However, stent length should be longer than the measured lesion length since choosing the exact diameter will not cover the plaque elongification secondary to the dilation process which is specifically significant in SVGs because of the softness of the plaque.     

Coronary stent fracture: The hidden truth of a problem more common than stent thrombosis

Embolization of athero‐thrombotic material during primary percutaneous coronary intervention is a common cause of periprocedural complication. Methods developed to reduce embolization include thrombus aspiration, and distal protection. We report five cases of primary percutaneous intervention to coronary arteries that contain large amounts of thrombus, using a novel mesh covered stent. The mesh covering of the stent is designed such that it is theoretically able to ensnare thrombus and thus prevent distal migration of embolic material. In all cases, TIMI grade III flow was achieved at the end of the procedure, despite the extensive thrombus burden. © 2009 Wiley‐Liss, Inc.     

Persistent and proximal migration of a large coronary thrombus during percutaneous coronary intervention in the setting of acute Q-wave myocardial infarction.

We describe a patient with an acute inferior myocardial infarction. Patient was taken to the cardiac catheterization laboratory for primary angioplasty. Angiography revealed 100% occluded proximal right coronary artery (RCA). After initial balloon angioplasty of the occluded RCA, a very large mobile thrombus was seen in the proximal RCA. Despite multiple stenting, suctioning through the guide catheter lumen, and intracoronary thrombolytic therapy, the thrombus persisted and migrated proximally after each stenting. However, patient did well despite of persistent large thrombus burden in the proximal RCA on aggressive antithrombotic treatment.     

A case in which stent insertion is considered to have triggered contrast medium-induced coronary vasospasm.

A Gianturco-Roubin II (GR-II) stent was inserted in a 75-year-old man who developed restenosis of the right coronary artery (RCA) after percutaneous transluminal coronary angioplasty (PTCA). Although the vessel became partially occluded after 7 months, it was redilated by PTCA. Follow-up angiography of the RCA and left coronary artery (LCA) was performed 3 months later. Chest pain with bradycardia and hypotension occurred immediately after this examination, and ST elevation appeared in ECG leads II, III, and aVF. Repeat angiography of the RCA confirmed complete occlusion due to a spasm at a site proximal to the GR-II stent. The spasm was resolved by intracoronary infusion of isosorbide dinitrate (ISDN), and PTCA was carried out for extensive recurrent restenosis of the RCA; however, vascular dissection developed at the distal end of the GR-II stent. Therefore, a Palmaz-Schatz (P-S) stent was placed such that its proximal end overlapped the distal end of the GR-II stent. Follow-up angiography 3 months later showed no restenosis, but an episode of vasospasm similar to the previous one occurred immediately after left ventriculography. The RCA was completely occluded proximal to the GR-II stent because of spasm. Although this spasm was gradually relieved by intracoronary infusion of ISDN, marked spasm was also observed distal to the P-S stent; complete relief was achieved by infusion of additional ISDN.     

Stent thrombosis after complex multivessel stenting in an elderly patient

We report a challenging case in terms of procedural difficulty as well as long‐term patency. Multivessel stenting procedures for long subtotal occlusions in the right coronary artery (RCA) and left anterior descending coronary artery (LAD) were successfully performed in an 84‐year‐old female who had complications of severe left ventricular dysfunction and a recent history of gastric ulcer bleeding. Two bare‐metal stents were successfully deployed in the mid and distal RCA. A drug‐eluting stent could only be deployed in the proximal RCA. Two drug‐eluting stents were deployed in the proximal LAD and LMT. Late stent thrombosis in the proximal RCA occurred about 3 months later. We speculated that a lack of aspirin and bare metal stent restenosis were the reasons for the late stent thrombosis. This case was very challenging in terms of balancing the risk of ischemia and bleeding after coronary stent deployment. © 2010 Wiley‐Liss, Inc.     

Coronary artery embolism from infectious endocarditis treated with catheter thrombectomy using a GuideLiner catheter

A 27‐year‐old male with history of IV drug use and recurrent endocarditis necessitating bioprosthetic mitral and tricuspid valve replacements presented with 2 weeks of fevers and chest pain. ECG revealed inferior ST‐elevation myocardial infarction and he was taken urgently to the cardiac catheterization laboratory. Coronary angiography revealed thrombotic occlusion of the distal right coronary artery (RCA) with no angiographic evidence of atherosclerotic disease. Aspiration thrombectomy was performed followed by rheolytic thrombectomy. Despite multiple attempts at thrombectomy, significant residual organized thrombus persisted in the distal RCA. Therefore, further thrombectomy was performed by placing a GuideLiner catheter (Vascular Solutions, Minneapolis, MN) deep within the right coronary artery near the bifurcation into the posterior descending and posterior left ventricular arteries. After repeat aspiration, there was significant improvement with thrombolysis in myocardial infarction 3 flow. Intravascular ultrasound of the RCA revealed a normal‐appearing vessel without evidence of atherosclerotic disease and mild residual thrombus. The decision was made to not pursue stent placement, given the concern for a likely embolic source. Following the procedure, the patient's chest pain resolved and his ST‐segments normalized. © 2015 Wiley Periodicals, Inc.     

Use of PTFE-covered stent in acute myocardial infarction of aneurysmatic coronary artery

Coronary artery aneurysms are reported between 0.1-4.9% in coronary angiographies. Vessel wall weakening, inflammation and endothelial damage play a role in their development. They may compromise the coronary flow and play a source for recurrent embolization of thrombus fragments. Here we report a patient with coronary artery aneurysm in left anterior descending artery with a critical thrombosed proximal segment and resulting in acute myocardial infarction. Coronary artery aneurysm is managed with polytetrafluoroethylene (PTFE) covered stent and proximal infarct related segment is treated with a bare metal stent. Coronary patency is provided without any obvious complication at the end of the procedure.     

Retrograde balloon hemostasis

Despite improvements in current devices and techniques for complex chronic total occlusion (CTO) percutaneous coronary intervention (PCI), procedural complications, including coronary perforation, still occur and could be life-threatening. A patient with a history of multivessel coronary artery disease and a CTO of the right coronary artery (RCA) underwent successful retrograde crossing of an RCA CTO. After wiring the CTO body and lesion dilatation, a drug-eluting stent was implanted in the distal RCA toward the posterior descending artery. A large Ellis type III perforation occurred at the distal edge of the stent. Septal crossing with a balloon and tamponade of the perforation site through the retrograde collaterals followed, as the RCA was not suitable to accommodate easily both the covered stent and the balloon simultaneously. This case report presents a novel approach the “septal retrograde ping-pong” technique, which demonstrates successful treatment of coronary perforations by utilizing a retrograde approach through a septal collateral. This technique proves to be effective in situations where the conventional antegrade balloon or covered stent delivery methods are not feasible or unsuccessful. This innovative approach offers a promising alternative for managing challenging cases of coronary perforations, providing new insights and potential solutions for interventional cardiologists.     

"Fogarty-like" removal of large coronary thrombus

In order to avoid distal embolization in patients undergoing emergency percutaneous coronary intervention for ST-elevation myocardial infarction, both thrombectomy and distal protection devices have been evaluated with conflicting effects on myocardial perfusion. However, the removal of massive coronary thrombus is always problematic, and failure of standard approaches might result in severe microvascular damage. We report a case of the unusual use, in a "Fogarty-like" fashion, of the Spidertrade mark filter to trap and remove a large thrombus that was refractory to aspiration and balloon dilatation before stent implantation in a proximal, infarct-related coronary artery.     

A novel minimal-invasive model of chronic myocardial infarction in swine

BACKGROUND: Most animal studies on myocardial infarction (MI) have used open-chest models with direct surgical coronary artery ligation, which imply local as well as generalized side effects of major surgery. Some closed-chest models of MI have been established, mainly using catheterization techniques with coronary artery embolization, balloon occlusion, and intracoronary injection of thrombogenic agents. The aim of this study was to develop a closed-chest technique of chronic coronary artery occlusion at a selected location with subsequent thrombus formation without use of balloon inflation or thrombotic chemical agents. METHODS AND RESULTS: A coronary angiography via the carotid artery was performed using a 7 F guiding catheter in 21 pigs. After insertion of a percutaneous transluminal coronary angioplasty (PTCA) guide wire into the distal coronary artery, a vessel-size adapted flexible foreign body comprising an open-cell sponge was advanced into the coronary artery via the guide wire by a non-inflated PTCA balloon. Five min after removal of the guide wire and the balloon catheter, total coronary artery occlusion was documented by angiography. Retrograde thrombosis of the coronary artery occurred in three animals. After one week, total vessel occlusion at the previously selected location was visualized by coronary angiography in animals that had survived. Macroscopic analysis demonstrated the foreign body with subsequent thrombus formation in the coronary artery and distal MI. Post-mortem histological analysis revealed myocardial necrosis and granulocyte infiltration at the margin of the infarction, without damage to remote myocardium. CONCLUSIONS: This new easy-to-perform closed-chest technique provides reproducible chronic coronary artery occlusion at a selected location with subsequent MI. It avoids major surgery and thoracotomy and does not require balloon inflation or intracoronary injection of thrombotic or chemical agents.     

Myocardial infarction in a youngster Due to giant coronary aneurysm

A 22‐year old male presented with acute inferior wall myocardial infarction. Coronary angiogram revealed normal left coronary arteries and a giant coronary aneurysm in Right coronary artery (RCA). Primary angioplasty of RCA was performed. Large thrombus burden was retrieved with aspiration device and coronary flow restored. However, despite best efforts some thrombus remained and decision to stent was deferred to a later date. Dimensions of aneurysm on quantitative coronary angiogram were 15 mm in width and 46 mm in length. Two weeks later coronary angiogram revealed normal flow in RCA without any angiographically visible thrombus. PCI was performed with two 3.0 × 28 mm Covered stents, Graft Master (JoStent) deployed across the aneurysm, overlapping each other. This completely sealed the aneurysm and intravascular ultrasound confirmed no leakage through the covered stents. Patient remains asymptomatic 2 months post procedure on triple antiplatelet therapy. © 2011 Wiley‐Liss, Inc.     

Late coronary thrombosis secondary to implantation of paclitaxel-eluting stent without restenosis of conventional stents

A male 39 year-old patient with post-infarction angina. The coronary angiography showed total proximal obstruction of right coronary artery (RCA), obstructive lesions of 95% of the anterior descending artery (ADA), 80% of the second left marginal branch (LM2), and 95% of the circumflex artery (CXA). The patient was successfully implanted with a Taxus 3.0 x 24 mm stent and an Express 2.75 x 24 mm stent in the proximal and distal thirds of the RCA, respectively, and with an Infinnium 3.0 x 24 mm stent in the ADA. After seven months, the patient had an anterior acute myocardial infarct (AMI) due to thrombosis of the Infinnium stent and restenosis of the Taxus stent, with no loss of results in the conventional stents.     

Unusual balloon rupture during direct stenting with a TaxusExpress stent in a venous graft complicated by vessel rupture: a device-related fatal event

A 70-year-old male with a prior coronary artery bypass operation presented with increasing episodes of chest pain. Coronary angiography revealed severe disease of the left anterior descending artery (LAD), CX, and RCA. A left internal mammary artery to LAD was patent. A jump venous graft, with four distal anastomoses, had two significant stenoses. Percutaneous coronary intervention with distal protection, and direct stenting with a drug-eluting stent, was planned. A 3.00 x 16 mm TaxusExpress (Boston Scientific) was used. At an inflation pressure of 10 atm the stent balloon seemed to extend 20 mm proximally with a diameter of 4.5 mm, and the balloon ruptured. Angiography showed rupture of the vessel proximal to the implanted stent, and the patient developed severe hypotension. The rupture was treated with a covered stent and pericardiocentesis was performed with evacuation of 600 mL blood. However, it was not possible to resuscitate the patient, who died due to severe pump failure and incessant ventricular fibrillation.     

The combined use of stent retriever and neuro‐aspiration as successful bail‐out reperfusion strategy in a patient with embolic myocardial infarction

Embolic myocardial infarction account for ≈3% of all ST‐segment myocardial infarction and represents a challenge often left no‐reperfused because current thrombectomy technologies are inefficient to grab thrombus wedged into distal coronary arteries. We present the case of a 34‐year‐old man who presented with anterior STEMI and a proximal left anterior descending coronary artery ulcerated plaque with a great thrombus burden, which led to distal embolization. Failure of several attempts of manual and rheolytic thrombectomy, led us to use the “Solumbra technique”, the combined use of stent retriever and Penumbra catheter was successful in restoring patency and flow.     

Results of saphenous vein graft stent implantation: single center results from use of oversized balloon catheters

The results and complications of a single-center experience of stent implantation in old saphenous vein grafts (SVGs) need to be defined. The authors studied their initial consecutive 92 patients (125 stents, 1.4 stents/per patient) with a mean age of 67+/-9 years. The patients' mean saphenous vein graft (SVG) age was 10+/-4 years, and the mean left ventricular ejection fraction was 46%+/-15. Patient population included unstable angina (65%), stable angina (10%), myocardial infarction (21%), and silent ischemia (4%). The authors implanted 122 Palmaz-Schatz/biliary and three Gianturco-Roubin stents. They aimed at a balloon-artery ratio of 1.1/1.0. Procedural success, defined as stent deployment with <50% stenosis without death/Q-wave myocardial infarction/coronary artery bypass grafting (MI/CABG) was 95%. The mean luminal diameter (MLD) increased from 0.6+/-0.5 to 3.3+/-0.8 mm (p<0.001) and mean SVG stenosis diameter was decreased from 80%+/-14 to -10%+/-11 (p<0.001). Angiographic SVG lesions exhibited thrombus (17%), ulceration (38%), and plaque rupture (28%). Sixty-two patients were treated with warfarin and aspirin and 30 with ticlid and aspirin. Complications included death in three patients (3.3%) who sustained subacute stent thrombosis, and two of three had Q-wave MI. Distal embolization occurred in seven patients (8%); six of seven sustained a non Q-wave acute myocardial infarction (AMI); and one of seven a Q-wave MI. Eight (9%) patients had major groin hematoma, two had pseudoaneurysm (2.2%), one had arteriovenous (A-V) fistula (1.1%), two had vascular surgery (2.2%), nine had blood transfusion (9.8%), and three had stent migration (3.3%). Single-center experience with stents in SVGs indicates a highly successful procedural and angiographic immediate result. However, it was complicated by significant risk of non Q-wave MI due to distal coronary embolization which may affect prognosis.     

New technique to seal a long giant coronary aneurysm with PTFE-covered stents: a case report.

We report a case with a large aneurysm of right coronary artery (RCA) associated with coronary artery disease. The aneurysm was sealed with two PTFE-covered stents using a sequential technique from proximal to distal to overcome the lack of long PTFE-covered stents and existence of complex coronary anatomy. A bare metal stent was subsequently deployed to treat a lesion in the mid part of RCA. At 4-month follow-up, aneurysm was completely sealed and no restenosis occurred. Usage of sequential PTFE-covered stents enables treatment of large coronary artery aneurysms.     

Six months clinical, angiographic, and IVUS follow-up after PTFE graft stent implantation in native coronary arteries

INTRODUCTION: Restenosis remains a problem even after stent implantation. An important breakthrough could be the use of graft stents, functioning as a mechanical barrier between the blood flow and the vessel wall, and possibly inducing less restenosis by more limited hyperplasia and minimal transgraft tissue penetration. OBJECTIVE: To assess the acute and 6 months clinical, angiographic and IVUS results of a new balloon expandable coronary polytetrafluoroethylene (PTFE) graft stent (Jomed). METHOD: Ten patients with a short (< or = 15 mm length) de novo proximal stenosis in a large (> or = 3 mm diameter) coronary artery were treated by elective implantation of a graft stent (19 mm stent, 15 mm graft). Clinical assessment, quantitative coronary angiography (QCA) and intracoronary ultrasound (IVUS) were performed before, immediately after and 6 months after implantation. A stress test was also done at 6 months. RESULTS : The coronary arteries treated were: RCA in 7 patients, LCX in 2 patients, LAD in 1 patient. Mean balloon size was 3.7 mm diameter, and mean inflation pressure was 18 atm (min. 12, max. 23). Additional stenting was needed in 3 patients. Two patients showed a minimal rise in CK (< 250 IU/l) and 1 patient needed a transfusion. No patient experienced a (sub)acute nor late thrombosis. As shown in the table, no restenosis was seen in the body of the graft stent. In 2 patients a restenosis was detected in the proximal and/or distal parts of the stent which are not covered by the graft. In 1 patient a restenosis was found outside the stent. All patients remained asymptomatic with a negative stress test at 6 months follow-up (FU). [table in text] CONCLUSIONS: A graft stent could indeed reduce the restenosis rate after stenting, in the part of the stent covered by the graft, but the uncovered distal and proximal parts are the weak points in this type of stent. For this reason, technical ameliorations in the construction of this graft stent are needed, e.g. a complete coverage of the stent by the PTFE graft and less rigidity of the stent causing reduced vessel trauma at the edges of the stent during implantation.