Adjunctive thrombus aspiration and mechanical protection from distal embolization in primary percutaneous intervention for acute myocardial infarction

The Rescuing Role of Aggressive Thrombosuction in Elective Coronary Angioplasty

Thrombosuction plays a controversial role during primary percutaneous intervention (PCI). Landmark trials have demonstrated no additional role of thrombosuction during primary percutaneous intervention towards improving mortality and outcome during primary percutaneous intervention. We describe a rare elective coronary angioplasty where only aggressive thrombosuction (almost 150-200 mL) of blood from the coronary artery established the antegrade coronary flow and saved an octogenarian from impending sudden cardiac death (SCD). The present case describes the promising role of aggressive thrombosuction even during elective coronary intervention when a large dissection ends in acute total thrombotic occlusion of a coronary artery jeopardizing the antegrade coronary perfusion.

Acute myocardial infarction due to coronary embolism caused by a metastatic mass from lung cancer

BACKGROUND

Acute arterial embolism due to tumor embolus is a rare complication in cancer patients, even rarer is lung tumor embolization leading to acute myocardial infarction. We report a patient who had a diagnosis of acute myocardial infarction(AMI)which was brought on by a coronary artery embolism by a metastatic lung cancer tumor. Clinicians need to be aware that tumor embolism can result in AMI.

CASE PRESENTATION

An 80-yeal-old male patient presented with persistent chest pain for 2 h and his electrocardiogram(ECG)showed anterior ST-segment elevation myocardial infarction. Instead of implanting a stent, thrombus aspiration was performed. Pathological examination of coronary artery thrombosis showed that a few sporadic atypical epithelial cells were scattered in the thrombus-like tissue. Combined with immune phenotype and clinical history, metastatic squamous cell carcinoma is more likely.

CONCLUSIONS

We report a rare case of a patient who was diagnosed of AMI due to a coronary artery embolism by a metastatic mass from lung cancer. Since there is no evidence-based protocol available for the treatment of isolated coronary thrombosis, we used thrombus aspiration to treat thrombosis rather than implanting a stent.

Low Ankle-Brachial Index is Associated with Microvascular Coronary Obstruction After Primary PCI

Introduction

Percutaneous coronary intervention (PCI) has improved recanalization of infarct-related arteries (IRA); however, TIMI-III flow does not always mean an efficient myocardial reperfusion. Myocardial blush grade (MBG) is used as a predictor for coronary microvascular obstruction. We assessed the association between ankle-brachial index (ABI), a widely used method for diagnosis of peripheral arterial disease (PAD), and coronary microvascular obstruction (MVO) as detected by MBG after primary PCI.

Patients and Methods

The study included 335 patients with ST-elevation myocardial infarction who had primary PCI. History taking, clinical examination, laboratory assessment, ECG and Echocardiography were done for every participant. MBG was assessed for patients after PCI procedure. ABI for all participating patients was calculated.

Results

Two hundred and sixty-one patients fulfilled the inclusion criteria with mean age 58.8 ± 10.7 years, 84% were males. Sixty-one percent had anterior wall myocardial infarction. After primary PCI, despite achieving TIMI flow III in all study patients, only 37% had normal MBG. There was a statistically significant relationship between MBG and site of infarction, left ventricular ejection fraction and ABI. Low ABI was found to predict poor MBG.

Conclusion

Coronary artery disease (CAD) is well linked to PAD. MBG can be used to assess coronary MVO after primary PCI. Poor MBG is associated with low ABI. This could establish a relationship between PAD and coronary MVO after primary PCI.

A Ghost in Coronary Artery - Coronary Artery Embolism After Discontinuation of Rivaroxaban in a Patient With Atrial Fibrillation: Case Report and Review of Literature

Coronary artery embolism (CAE) is a rare clinical entity that can cause acute myocardial infarction (AMI). The exact prevalence of coronary artery embolism is unknown. CAE was found to be associated with conditions that can lead to thrombo-embolism, including infective endocarditis, atrial fibrillation, mitral valve disease, valve surgery. Herein, we report a 78-year-old male with a past medical history of atrial fibrillation on rivaroxaban who presented to the hospital emergency department complaining of chest pain. The patient's anticoagulation therapy was recently held due to a concern for gastrointestinal bleeding. After further evaluation of the patient's symptoms and reviewing his electrocardiogram (ECG) which showed ST-depression in lateral leads and ST-elevation in aVR, urgent cardiac catheterization was done which showed left main coronary artery thrombosis extending into the left anterior descending artery (LAD) and left circumflex artery (LCX). The patient was started on a heparin drip and underwent a successful aspiration thrombectomy with subsequent improvement in his symptoms.

Coronary Embolism: A Systematic Review

BACKGROUND

Coronary embolism is a rare and potentially fatal phenomenon that occurs primarily in patients with valvular heart disease and atrial fibrillation. There is a lack of consensus regarding the diagnosis, treatment, and management of coronary embolism, leaving management at the discretion of the treating physician. Through this review, we aim to establish a better understanding of coronary embolism, and to identify treatment options - invasive and non-invasive - that may be used to manage coronary embolism.

METHODS AND RESULTS

Our systematic review included 147 documented cases of coronary embolism from case reports and case series. The average age of our population was 54.2 ± 17.6 years. The most common causes of coronary embolism included infective endocarditis (22.4%), atrial fibrillation (17.0%), and prosthetic heart valve thrombosis (16.3%). Initial presentation was indistinguishable from an acute coronary syndrome (ACS) due to coronary atherosclerosis, and the diagnosis required a high level of suspicion and evaluation with angiography. Treatment strategies included, but were not limited to, thrombectomy, thrombolysis, balloon angioplasty and stent placement. Myocardial dysfunction on echocardiography was observed in over 80% of patients following coronary embolism. "Good outcomes" were reported in 68.7% of case reports and case series, with a mortality rate of 12.9%.

CONCLUSION

Coronary embolism is an under-recognized etiology of myocardial infarction with the potential for significant morbidity and mortality. To improve outcomes, physicians should strive for early diagnosis and intervention based on the underlying etiology. Thrombectomy may be considered with the goal of rapid restoration of coronary flow.

Clinical analysis of acute myocardial infarction caused by coronary embolism

Background

This study aims to investigate the clinical and angiographic features in patients with acute myocardial infarction (AMI) induced by coronary artery embolism.

Methods

Clinical data of five patients with AMI induced by coronary artery embolism were analyzed retrospectively.

Results

One patient had left atrial myxoma, one patient had non-valvular atrial fibrillation, and three patients had rheumatic heart disease. Furthermore, one patient had mitral mechanical valve prostheses, two patients had atrial fibrillation. Coronary angiography showed the absence of significant atherosclerostic lesions in the coronary arteries except infarct related artery in five patients. Angiography suggested the presence of IRA occlusion caused by embolism.

Conclusions

The status for AMI due to coronary artery embolism usually expresses embolic material originating from the left heart chambers. Rheumatic heart disease and atrial fibrillation are the common reasons for coronary artery embolism. Coronary artery occlusion is the common performance in the results of primary coronary artery angiography. Sometimes it expresses visible signs of embolism.

The Effect of Interventional Treatment in Acute Myocardial Infarction on ST Resolution: A Comparison of Coronary Angioplasty with Excimer Laser Angioplasty

The treatment methods for acute myocardial infarction (MI) have started to change in the new millennium. Myocardial perfusion (ST-segment resolution) is the target rather than achieving TIMI-III flow in the infarct-related artery. In this study the authors compared the effect of percutaneous transluminal coronary angioplasty (PTCA) and excimer laser angioplasty (ELCA), which was accepted as one of the thrombolysis methods, on ST-segment resolution. A stent was applied after ELCA to 36 patients (4 women, 32 men; mean age 50.44 ±9.8 years) in group I and a stent was applied after balloon angioplasty to 44 patients (5 women, 39 men; mean age 50.77 ±12.2 years) in group II. Fisher’s exact test was used in the analysis of data, and p<0.05 was accepted as significant. There was no difference between the groups with respect to symptom duration, time to angioplasty, risk factors, infarct localization, stent diameter, and length. TIMI-III flow was achieved in 33 patients (92%) in group I and in 40 patients (91%) in group II. There was no statistical difference in TIMI flow between the groups. In group I, complete ST resolution was observed in 75% (27/36) of the patients, partial resolution in 22% (8/36), and resolution was unsuccessful in 3% (1/36). In group II, complete, partial, and unsuccessful ST resolution were 41% (18/44), 45% (20/44), and 14% (6/44), respectively. The mean ST resolution was 82.78 ±11.8% in group I and 66.36 ±10% in group II (p=0.001). ST segment resolution, which is a good predictor of tissue perfusion, was higher with ELCA than with balloon angioplasty. These findings should be supported by large randomized studies.

Coronary competitive reverse flow: Imaging findings at CT angiography and correlation with invasive coronary angiography

OBJECTIVE

To study the imaging features of coronary competitive reverse flow and incidence of a "reverse attenuation gradient" in coronary CT angiography (CTA) with correlation to invasive coronary angiography (ICA).

METHODS

Patients who had undergone coronary CTA and ICA within 2 weeks were retrospectively identified in our database and reviewed. All cases with ICA-confirmed competitive reverse flow or chronic total occlusions (CTOs) were included for further analysis. The "reverse attenuation gradient sign" was defined as a reverse intraluminal opacification gradient of vessels which showed higher opacification in more distal compared with proximal segments. ICA findings were recorded and served as the reference to identify the clinical implications of this sign.

RESULTS

In total, 134 patients (mean age, 68.1 ± 11.3 years; range, 38-90 years; 104 men) were included in our study. ICA revealed 11 cases of coronary competitive reverse flow and 123 cases of CTO. A reverse attenuation gradient sign was present in 9 of 11 patients (82%) with coronary competitive reverse flow and 72 of 123 (59%) chronically occluded coronary arteries. Myocardial bridges, distal collateral filling, as well as direct visualization of collateral connection were all more frequent in cases with coronary competitive reverse flow group compared with cases with a CTO.

CONCLUSIONS

The reverse attenuation gradient sign distal to an upstream coronary severe stenosis indicates the presence of competitive collateral flow. Coronary CTA is able to correctly detect coronary competitive collateral flow and differentiate it from CTOs.

Rationale and design of the INFUSE-AMI study: A 2 × 2 factorial, randomized, multicenter, single-blind evaluation of intracoronary abciximab infusion and aspiration thrombectomy in patients undergoing percutaneous coronary intervention for anterior ST-segment elevation myocardial infarction

BACKGROUND

Whether thrombus aspiration and local glycoprotein IIb/IIIa administration reduce infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not been established in multicenter studies.

DESIGN

INFUSE-AMI is a multicenter, open-label, controlled, single-blind randomized study enrolling 452 subjects with anterior STEMI and an occluded proximal or mid-left anterior descending artery with thrombosis in myocardial infarction 0, 1, or 2 grade flow undergoing primary PCI with bivalirudin anticoagulation. Subjects are randomized in a 2 × 2 factorial to one of the following 4 arms: (1) local infusion of abciximab using the ClearWay RX Local Therapeutic Infusion Catheter (ClearWay, Atrium Medical Corp, Hudson, NH) after aspiration with a 6F Export Aspiration Catheter (Medtronic, Inc, Minneapolis, MN), (2) local infusion of abciximab using the ClearWay RX Infusion Catheter and no aspiration, (3) no local infusion of abciximab and aspiration with a 6F Export Aspiration Catheter, or (4) no local infusion of abciximab and no aspiration. The primary end point is infarct size (percentage of total left ventricular mass) at 30 days measured by cardiac magnetic resonance imaging. Other secondary end points include microvascular obstruction by cardiac magnetic resonance imaging at 5 days, ST-segment resolution, angiographic myocardial perfusion, thrombus burden, angiographic complications, and clinical events through 1-year follow-up. Safety end points include major and minor bleeding.

SUMMARY

INFUSE-AMI is testing the hypothesis that the intracoronary administration of an abciximab bolus with or without thrombus aspiration before stent implantation compared to no infusion with or without thrombus aspiration reduces infarct size among patients undergoing primary PCI for anterior STEMI who are treated with bivalirudin.

Acute Myocardial Infarction due to Coronary Artery Embolism in a Patient with Mechanical Aortic Valve Prosthesis

Previous cases of coronary embolism as a cause of myocardial infarction (MI) in association with prosthetic mechanical valves have been reported, but the fact that the patient was not aware of the importance of maintaining anticoagulation therapy is relevant in this case. A 16-year-old female was referred for primary coronary intervention due to subacute anterolateral ST elevation MI, after she decided to discontinue warfarin therapy three weeks before. Coronary angiography showed distal occlusion of the left anterior descending coronary artery with an image suggesting embolic material. Conventional echocardiography demonstrated akinesia of anteroseptal, inferior, and posterior segments of the left ventricle, with severe systolic dysfunction, beyond the intraventricular thrombus. The presence of mechanic aortic prosthesis and no anticoagulation therapy are highly suggestive of coronary embolism as the cause of MI. This case report confirms that patient education is vital in our struggle to prevent this complication in high-risk patients.

A case of acute myocardial infarction caused by distal embolization of a left main coronary artery thrombus

Coronary embolism is an uncommon cause of myocardial infarction. A 48-year-old male presented with typical chest pain of an MI. There was no definite ST segment change on electrocardiogram (ECG) and no elevation of myocardial enzymes. Coronary angiography (CAG) revealed occlusion of the distal left anterior descending coronary artery (dLAD), the distal left circumflex coronary artery (dLCX), the diagonal branch (D) and the obtuse marginal branch (OM), with a large filling defect in the left main coronary artery (LMA) that caused the myocardial infarction. We considered the possibility that coronary embolization was caused by the migration of a thrombus in the LMA during CAG. We did balloon angioplasty in the dLAD, dLCX, OM and D and treated the patient with glycoprotein IIb/IIIa receptor antagonist. However, thrombi remained in the dLAD, OM, and dLCX. After 3 days of anti-thrombotic treatment, follow-up CAG revealed only slight resolution of thrombi in the LAD. After triple antiplatelet agent medication for 1 year, a follow-up CAG showed a resolution of the thrombi in all coronary arteries.

Time-dependent benefit of initial thrombosuction on myocardial reperfusion in primary percutaneous coronary intervention

BACKGROUND

In ST-segment elevation acute myocardial infarction (STEMI), dislodgement of thrombus within the culprit artery during primary percutaneous coronary intervention (PCI) may cause distal embolisation and impaired myocardial reperfusion. Clinical results of thromboembolic protection strategies have been controversial. We conducted this study to investigate whether the benefit of thrombus removal is time dependent.

METHODS

Seventy-four STEMI patients within 12 h from onset were randomised to receive either primary PCI with initial thrombosuction (IT) or standard strategy. Results were analysed in subgroups according to the onset-to-lab time intervals (subgroup 1: 0-240 min, subgroup 2: 241-480 min and subgroup 3: 481-720 min).

RESULTS

The primary end-points were improvements in thrombolysis in myocardial infarction flow (DeltaTIMI) and myocardial blush grade (DeltaMBG) postprocedure. Better DeltaTIMI (2.2 +/- 1.1 vs. 1.5 +/- 1.3, p = 0.014) and DeltaMBG (2.3 +/- 1.1 vs. 1.0 +/- 1.5, p < 0.001) were observed in IT patients, compared with standard PCI patients. In onset-to-lab time subgroup analysis, the difference between IT and standard PCI is significant only in subgroup 2 (DeltaTIMI 2.6 +/- 1.0 vs. 1.3 +/- 1.2, p = 0.007; DeltaMBG 2.6 +/- 0.9 vs. 1.0 +/- 1.1, p = 0.010), but not in the other two subgroups.

CONCLUSIONS

This prospective randomised study shows that primary PCI with IT may improve epicardial flow and myocardial reperfusion in patients with STEMI, and this benefit is the most significant in patients treated within 4-8 h after symptom onset.

Primary angioplasty and routine utilization of thrombus aspiration devices: feasibility and results in a consecutive series of 486 patients

BACKGROUND

Primary percutaneous transluminal coronary angioplasty (PTCA) is the treatment of choice for acute ST-segment elevation myocardial infarction (STEMI) in high-volume centres with experienced operators, but is often limited by a suboptimal microvascular perfusion due to distal embolization and impaired myocardial perfusion. The present study investigates whether routine use of thrombus aspiration (TA) devices is feasible in daily practice, along with its safety and effectiveness.

METHODS

This study is based on a series of 486 consecutive STEMI patients treated at our single institution by the same three operators (from 2001 to 2005). They underwent primary PTCA with or without TA according to these angiographic features: infarct related artery (IRA) diameter>or=3 mm; thrombotic occlusion or angiographic evidence of thrombus; absence of severe proximal tortuosity or calcification. We evaluate the efficacy of TA in terms of procedural success, coronary thrombolysis in myocardial infarction (TIMI) flow, myocardial blush grade (MBG), resolution>or=50% of ST segment elevation, and clinical events during hospital stay and at 6-month follow-up.

RESULTS

A total of 486 primary PTCAs were performed, 217 (44.6%) with TA as a first device using RESCUE (n=65), EXPORT (n=140) and DIVER-CE (n=12) catheters. In 141 (65%) cases, macroscopic material was aspirated. The patients submitted to TA were more often males (84.7% versus 71.7%, P<0.05) and younger (age: 61.02+/-11.91 versus 64.47+/-10.59 years, P<0.01) than patients treated with traditional PTCA and the IRA was more frequently occluded at angiography (basal TIMI 0: 70.5% versus 47.9%). Application of the TA did not increase the complexity of the procedure (door-to-balloon times, minutes of fluoroscopy and amount of dye). TA alone was effective to restore TIMI 3 flow in 187 cases (86.2%) as a first device and in three other cases (1.4%) after predilatation with balloon. Direct stenting without predilatation was possible in 144 cases (66.4%) after TA. TA was not effective in 27 cases (12.4%) and this subgroup had both angiographic and clinical unfavourable results in comparison with the effective TA group (final TIMI 1 in 11.1% versus 0.5%, P<0.015; final MBG 1 in 55.5% versus 9.5%, P<0.001; lack of ST segment resolution>or=50% in 44.4% versus 7.9%, P<0.001; in-hospital mortality 14.8% versus 2.6%, P<0.05 and mortality at 6 months 18.5% versus 3.1%, P<0.05). In the whole TA population, final TIMI 3 flow was achieved in 203 cases (93.5%), final MBG 3 in 145 cases (66.8%) and ST segment resolution>or=50% in 185 cases (85.2%), in-hospital mortality was 4.1% and cumulative mortality at 6-month follow-up was 5.5%.

CONCLUSIONS

In our case series, 486 consecutive unselected patients with STEMI were treated in a primary PTCA high-volume centre using TA devices. Our study demonstrates that, in STEMI patients treated with primary PTCA, a routine strategy with TA before angioplasty guided by angiographic selection criteria is feasible in almost 50% of cases, is safe and effective, does not increase procedural time and offers good results in terms of tissue perfusion, both epicardial (TIMI flow) and myocardial (MBG, ST regression). When successfully performed, TA identifies a population with favourable in-hospital and 6-month outcome.

Thrombosuction utilizing an export aspiration catheter during primary percutaneous coronary intervention in acute myocardial infarction

PURPOSE

Effective myocardial reperfusion after primary PCI for an AMI in lesions with a thrombus is limited by distal embolization and the slow/no reflow phenomenon. We evaluated the efficacy of a thrombus reduction technique using an export aspiration catheter for thrombosuction during primary PCI.

MATERIALS AND METHODS

We analyzed 62 patients with AMIs who underwent primary PCI and had a thrombi burden during thrombosuction using an EAC (EAC group; n=31) or without thrombosuction (control group; n=31).

RESULTS

Thrombosuction with an EAC was performed safely in all the patients in EAC group without any complications. After the PCI, restoration to a TIMI flow grade 3 was significantly more frequent in the EAC group (26/31 vs. 20/31, p < 0.05). However, the TIMI perfusion grade did not differ between the two groups. Further, the corrected TIMI frame counts were lower in the EAC group (23.9 +/- 15.1 vs. 34.8 +/- 22.5, p < 0.05). Although there was no statistical significance, a greater incidence of distal embolization was observed in the control group (16.1%, 5/31) as compared to the EAC group (0/31) (p= 0.056). However, the incidence of major adverse cardiac events at 1 and 6 months did not differ between the two groups.

CONCLUSION

For AMIs, thrombosuction with an EAC before or during PCI is a safe and potentially effective method for restoration of the coronary flow.

Comparison of 30-day outcomes in patients <75 years of age versus >or=75 years of age with acute myocardial infarction treated by primary coronary angioplasty

We reviewed 1,087 consecutive patients treated by primary coronary angioplasty for acute myocardial infarction; 309 were >or=75 and 778 were <75 years of age. Compared with the younger group, the older group had higher 30-day (8.1% vs 4.0%, p = 0.0057) and cardiac (6.5% vs 3.6%, p = 0.038) mortality rates. Successful reperfusion was achieved in the 2 groups at a similarly high rate (91.6% and 92.9%, p = 0.45). Successful compared with unsuccessful angioplasty decreased 30-day mortality rates in the older group (6.0% vs 30.8%, p <0.0001) and in the younger group (3.2% vs 14.5%, p <0.0001). When reperfusion was successful, the cardiac mortality rate in older patients was not significantly greater than that in younger patients (4.6% vs 2.8%, p = 0.14). By multivariate analysis in all 1,087 patients, overt cardiogenic shock on admission (odds ratio 44.7, 95% confidence interval 22.0 to 91.1, p <0.0001) and unsuccessful reperfusion (odds ratio 9.40, 95% confidence interval 4.11 to 21.5, p <0.0001) were found to be independent predictors of 30-day mortality, whereas age >or=75 years (odds ratio 1.79, 95% confidence interval 0.91 to 3.50, p = 0.090) was not. In conclusion, aggressive angioplasty in older patients improves prognosis.

Coronary embolism causing myocardial infarction in a patient with mechanical aortic valve prosthesis

Coronary embolism as a cause of myocardial infarction is an uncommon but important entity both in terms of aetiology and treatment. Previous cases of coronary emboli in association with prosthetic mechanical valves have been reported previously but the mechanism of pharmacology and lack of patient awareness of medication importance is quite unique in this case. A 65-year-old male presented to the emergency room with an anterior ST elevation myocardial infarction after 14 h of symptoms. Past medical history included aortic valve replacement with a mechanical tilting-disc valve 18 months earlier for symptomatic severe calcific aortic stenosis. Pre-operative coronary angiography revealed normal coronary arteries. On this occasion, coronary angiography revealed an occluded LAD with an embolic occlusion at the midpoint of the vessel. Successful PTCA and stenting of the lesion were performed. Amazingly, the patient had decided 1 year earlier to stop taking his warfarin medication. He had begun taking a new "herbal remedy" which was helping with his joint pains but the combination with warfarin was causing excessive bleeding each day after facial shaving. He therefore decided to abruptly stop taking his warfarin without any medical advice. Embolic myocardial infarction is underdiagnosed and it is important to diagnose the source of embolism and treat the cause. Patient education is vital in our battle to prevent this entity in high-risk patients as in our case.

EMERALD, AIMI, and PROMISE: is there still a potential for embolic protection in primary PCI?

The recent trials of routine use of embolic protection devices for primary percutaneous coronary interventions (PCI) (the EMERALD, PROMISE, and AIMI trials) have demonstrated neutral or even negative effects of these devices on myocardial reperfusion and final infarct size. Despite these results, there is still ground to believe that PCI-induced embolization may be clinically relevant in specific subsets of patients with acute myocardial infarction (AMI). Significant clinical consequences may be expected when embolization is quantitatively relevant and/or is qualitatively characterized by lipid-rich athero-embolism (as is the case of lipid core embolization through the ruptured cap of a fibro-atheroma). Future trials on embolic protection devices in primary PCI should adopt a selective, rather than a routine strategy, through the identification, by angiographic or intravascular imaging parameters, of patients at highest risk of clinically relevant embolization. Such trials should also adopt specific endpoints able to evaluate the effect of micro-embolization, which is currently far from optimally assessed by the standard markers of myocardial reperfusion.

Impact of intracoronary aspiration thrombectomy during primary angioplasty on left ventricular remodelling in patients with anterior ST elevation myocardial infarction

OBJECTIVE

To evaluate prospectively the impact on left ventricular (LV) remodelling of an intracoronary aspiration thrombectomy device as adjunctive therapy in primary percutaneous coronary intervention (PCI) in patients with anterior ST elevation myocardial infarction (STEMI).

METHODS

76 consecutive patients with anterior STEMI (65.3 (11.2) years, 48 men) were randomly assigned to intracoronary thrombectomy and stent placement (n = 38) or to conventional stenting (n = 38) of the infarct related artery. Each patient underwent transthoracic echocardiography immediately after PCI and at six months. At the time of echocardiographic control, major adverse cardiovascular events (MACE) in terms of death, new onset of myocardial infarction, and hospitalisation for heart failure were also evaluated.

RESULTS

After a successful primary PCI, patients in the thrombectomy group achieved a higher rate of post-procedure myocardial blush grade 3 (36.8% v 13.1%, p = 0.03) and effective ST segment resolution at 90 minutes (81.6% v 55.3%, p = 0.02). Six months after the index intervention, 19 patients (26.8%) developed LV dilatation, defined as an increase in end diastolic volume (EDV) >or= 20%: 15 in the conventional group and four in the thrombectomy group (p = 0.006). Accordingly, at six months patients treated conventionally had significantly higher end systolic volumes (82 (7.7) ml v 75.3 (4.9) ml, p < 0.0001) and EDV (152.5 (18.1) ml v 138.1 (10.7) ml, p < 0.0001) than patients treated with thrombectomy. No differences in cumulative MACE were observed (10.5% in the conventional group v 8.6% in the thrombectomy group, not significant).

CONCLUSION

Compared with conventional stenting, adjunctive aspiration thrombectomy in successful primary PCI seems to be associated with a significantly lower incidence of LV remodelling at six months in patients with anterior STEMI.

Early Administration of Intracoronary Verapamil Improves Myocardial Perfusion During Percutaneous Coronary Interventions for Acute Myocardial Infarction

BACKGROUND

Intracoronary calcium-channel blockers administered in the event of no reflow during percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI) have been shown to improve myocardial perfusion.

STUDY OBJECTIVE

To evaluate the effects of the administration of intracoronary verapamil before the occurrence of no reflow during direct PCI.

DESIGN AND SETTING

Single-center, nonrandomized, prospective study with a retrospective control group.

PATIENTS AND METHODS

From September 2001 to December 2003, 50 consecutive patients with AMI were prospectively enrolled for intracoronary verapamil treatment. Intracoronary verapamil was administered immediately prior to balloon inflation and at short intervals during the procedure thereafter. Retrospectively, 50 consecutive AMI patients who had undergone direct PCI and had not received intracoronary calcium-channel blockers were enrolled as control subjects. Patients with cardiogenic shock or platelet glycoprotein IIb/IIIa inhibitor were excluded. Thrombolysis in Myocardial Infarction (TIMI) flow grade, corrected TIMI frame count (CTFC), and TIMI myocardial perfusion grade (TMPG) were assessed prior to and following PCI by two independent cardiologists blinded to the procedures.

RESULTS

The two groups had similar baseline and post-procedural angiographic characteristics, although the patients who been administered verapamil received more stent implantations than the control subjects (84% vs 60%, p = 0.008). Post-procedural TIMI flow < 3 (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.12 to 1.30; p = 0.18) and TMPG (OR, 1.24; 95% CI, 0.46 to 3.34; p = 0.68) were not associated with the implantation of the stents. There were no significant difference in post-PCI TIMI flow (p = 0.68) and CTFC (p = 0.36) between patients treated with verapamil and the control subjects. Post-PCI TMPG was significantly better in patients treated with intracoronary verapamil (p = 0.003). Forty-two percent of the patients treated with verapamil were found to have TMPG-3, while only 14% of the control subjects were found to have the same degree of TMPG (p = 0.004). Treatment with intracoronary verapamil (OR, 0.26; 95% CI, 0.12 to 0.58; p = 0.001) and pre-PCI TIMI flow (OR, 0.54; 95% CI, 0.35 to 0.84; p = 0.006) were found by multiple logistic regression to be independent predictors of TMPG.

CONCLUSIONS

Early administration of intracoronary verapamil during direct PCI improves post-procedural myocardial perfusion, as evaluated by TMPG.

Eligibility for use of proximal or distal embolic protection devices during percutaneous intervention for acute myocardial infarction

Although there has been enthusiasm for using embolic protection devices in acute myocardial infarction, it is unclear how often these devices can be used in nonselected patients. The aim of this study was to evaluate potential eligibility for use of either proximal or distal embolic protection during primary or rescue percutaneous coronary intervention in a consecutive, nonselected population. We analyzed the angiograms of 259 consecutive patients with ST-segment elevation myocardial infarction to determine eligibility for use of either type of protection device. Overall, 202 (78%) patients had anatomy suitable for embolic protection, including 154 (59%) who were eligible for proximal protection, 128 (49%) who were eligible for distal protection, and 80 (31%) who were eligible for both devices. Patients eligible for proximal protection were more likely to have a right coronary culprit, whereas patients eligible for distal protection were more likely to have a lesion in the left anterior descending coronary artery.

X-sizer for thrombectomy in acute myocardial infarction improves ST-segment resolution: results of the X-sizer in AMI for negligible embolization and optimal ST resolution (X AMINE ST) trial

OBJECTIVES

We sought to compare, in a prospective randomized multicenter study, the effect of adjunctive thrombectomy using X-Sizer (eV3, White Bear Lake, Minnesota) before percutaneous coronary intervention (PCI) versus conventional PCI in patients with acute myocardial infarction (AMI) for <12 h and Thrombolysis In Myocardial Infarction (TIMI) flow grade 0 to 1. The primary end point was the magnitude of ST-segment resolution after PCI.

BACKGROUND

Despite a high rate of TIMI flow grade 3 achieved by PCI in patients with AMI, myocardial reperfusion remains relatively low. Distal embolization of thrombotic materials may play a major role in this setting.

METHODS

We conducted a prospective, randomized, multicenter study in patients with AMI <12 h and initial TIMI flow grade 0 to 1 who were treated with primary PCI. The magnitude of ST-segment resolution 1 h after PCI was the primary end point.

RESULTS

A total of 201 patients were included. Treatment groups were comparable by age (61 +/- 13 years), diabetes (22%), previous MI (8%), anterior MI (52%), onset-to-angiogram (258 +/- 173 min), and glycoprotein IIb/IIIa inhibitor use (59%). The magnitude of ST-segment resolution was greater in the X-Sizer group compared with the conventional group (7.5 vs. 4.9 mm, respectively; p = 0.033) as ST-segment resolution >50% (68% vs. 53%; p = 0.037). The occurrence of distal embolization was reduced (2% vs. 10%; p = 0.033) and TIMI flow grade 3 was obtained in 96% vs. 89%, respectively (p = 0.105). Myocardial blush grade 3 was similar (30% vs. 31%; p = NS). Six-month clinical outcome was comparable (death, 6% vs. 4% and major adverse cardiac and cerebral events, 13% vs. 13%, respectively). By multivariate analysis, independent predictors of ST-segment resolution >50% were: younger age, non-anterior MI, use of the X-Sizer, and a short time interval from symptom onset.

CONCLUSIONS

Reducing thrombus burden with X-Sizer before stenting leads to better myocardial reperfusion, as illustrated by a reduced risk of distal embolization and better ST-segment resolution.

Distal embolization during primary angioplasty: histopathologic features and predictability

BACKGROUND

Distal embolization during primary percutaneous coronary interventions (PCIs) may affect myocardial reperfusion. We evaluated the prevalence and features of embolization during primary PCI and its relationship with clinical and angiographic variables.

METHODS

Forty-six consecutive patients with acute myocardial infarction underwent primary PCI with a filter-based distal protection device. Histopathologic analysis was performed on retrieved embolic fragments, assessing the presence and relative amount of fibrin, necrosis, lipid droplets, collagen, mucopolysaccharides, and leukocytes, as well as the total debris volume. Such variables were related to baseline clinical and angiographic variables.

RESULTS

Embolic material was recovered in 41 (89%) of 46 cases, with a mean total debris volume of 1.2 +/- 2.2 mm3. Prevalent histopathologic patterns were organized thrombus (47%), fresh thrombus (29%), and plaque fragments (24%). At multivariate analysis, none of the baseline clinical variables considered significantly predicted the total debris volume. Among angiographic variables, angiographic signs of high thrombus burden (cut-off coronary occlusion pattern or large intracoronary minus image) independently predicted the total debris volume at multivariate analysis (odds ratio 15.8, P < .005). Compared with its nonuse, abciximab did not affect the total number and the mean total volume of embolized material (15 +/- 16 vs 10 +/- 8 fragments, 1.5 +/- 2.5 vs 1.0 +/- 1.9 mm3, respectively, for both P > .20), or its qualitative composition.

CONCLUSIONS

Distal embolization occurs in most patients during primary PCI and mainly consists of plaque fragments and partially organized thrombi, which are likely to be scarcely responsive to antiplatelet drugs. Baseline angiographic signs of a high thrombus burden are the only significant predictors of the extent of distal embolization.

Initial thrombosuction with subsequent angioplasty in primary coronary intervention—comparison with conventional strategy

BACKGROUND

Large thrombus burden remains challenging in the setting of acute myocardial infarct. Initial thrombosuction (IT) followed by actual angioplasty may be advantageous over conventional strategy in primary percutaneous coronary intervention (PCI).

METHODS

With a case-control design, 22 consecutive patients receiving primary PCI with IT were designated as group 1. Another 22 well-matched patients undergoing primary PCI with conventional strategy in the same period were enrolled as group 2. Clinical and angiographic outcomes, procedural parameters and resource usage were compared.

RESULTS

Baseline characteristics were comparable, including the symptom onset-to-needle time (250+/-101 vs. 261+/-149 min, p = NS). Total procedure time (33+/-14 vs. 47+/-20 min, p = 0.011), fluoroscopy time (10+/-6 vs. 16+/-10 min, p = 0.014) and contrast medium consumption (140+/-40 vs. 170+/-50 ml, p = 0.024) were all significantly reduced with group 1. No-reflow occurred less frequently with group 1 (5% vs. 32%, p = 0.046) during intervention, and TIMI 3 flow was established more quickly (19+/-10 vs. 30+/-20 min, p = 0.024). Final TIMI 3 flow rates and stent rates were similar. The time to myocardial enzyme peak was shorter with group 1 (9.7+/-3.1 vs. 12.8+/-6.3 h, p = 0.048), but no difference was found in 3 months cumulative major cardiac adverse event rates.

CONCLUSIONS

Primary PCI with IT achieves earlier reperfusion and is more efficient in terms of time and resource, comparing to conventional strategy.

Effects and Safety of Intracoronary Thrombectomy Using Transradial Application of the PercuSurge Distal Balloon Protection System in Patients with Early or Recent Myocardial Infarction

BACKGROUND

Distal embolization and no reflow are likely during primary percutaneous coronary intervention (PCI) on the large infarct-related artery (IRA), which mostly contains high-burden thrombus formation (HBTF) and plaque burden. Mechanical devices to prevent distal atheroembolism may be of importance for preserving reperfusion and microvascular integrity in IRA.

METHODS AND RESULTS

Between May 2002 and December 2002, transradial application (TRA) of the PercuSurge GuardWire device with 7-french arterial sheath was performed in 39 consecutive patients who experienced early (>12 h and </=7 days) or recent (>7 days and <14 days) myocardial infarction (MI) associated with large IRA (vessel size >/=3.5 mm with HBTF; group 1). Between January 2001 and April 2002, 64 consecutive patients who had early or recent MI associated with HBTF in IRA of a vessel size >/=3.5 mm received TRA of PCI with adjunctive tirofiban therapy but without using the adjunctive PercuSurge GuardWire device (group 2). The angiographic and clinical outcomes of both groups were compared in a chronologically consecutive manner. The procedural success rate and post-PCI myocardial blush grades were significantly higher in group 1 than in group 2 patients (all p values <0.05), whereas a combined incidence of vascular and bleeding complications and 30-day major adverse cardiac events (defined as death, reinfarction and repeated PCI of IRA) were significantly higher in group 2 than in group 1 patients (all p values <0.05).

CONCLUSIONS

Our data suggested that TRA using the PercuSurge GuardWire device during PCI for patients with early or recent MI and HBTF in IRA was safe and feasible. This mechanical device provided more additional benefit to patients in this clinical setting than a combination of conventional PCI and tirofiban therapy.

Thrombus aspiration prior to primary angioplasty in acute myocardial infarction: estimation of rescued myocardial tissue by return of ST-segment elevation

BACKGROUND

The goal of the study was to validate the clinical benefit of adjunctive thrombus aspiration prior to balloon or stent angioplasty in patients with acute myocardial infarction.

HYPOTHESIS

Adjunctive thrombus aspiration reduces no-reflow by eliminating peripheral thromboembolism.

METHODS

In all, 143 consecutive patients underwent primary angioplasty for acute myocardial infarction in our institution. We excluded patients with subacute stent thrombosis or bundle-branch pattern of the electrocardiogram (ECG) and divided the remaining 131 into two groups: 62 patients who underwent intervention without a thrombus aspiration device (Group 1) and 69 patients who were treated as soon as a specifically designed thrombus aspiration catheter became available at our institution (Group 2). The intention was to use thrombus aspiration in every suitable case with proximal occlusion of a major vessel. The reduction of the sum of ST-segment elevation following angioplasty as a marker of rescued myocardial tissue was compared between the two groups.

RESULTS

Thrombus aspiration was technically feasible in 23 of 25 attempted cases. The reduction of the sum of ST-segment elevation following intervention was 0.41 +/- 0.39 mV in Group 1 and 0.37 +/- 0.42 mV in Group 2 (p > 0.05).

CONCLUSIONS

Thrombus aspiration may be helpful during primary angioplasty in selected cases but does not improve the general outcome. Other reasons for "no-reflow," apart from peripheral thromboembolism, seem to be responsible for the lack of clinical benefit.

Impact of major side branch on periprocedural enzyme elevation and long-term outcome in patients undergoing percutaneous coronary intervention and brachytherapy for in-stent restenosis

Side branch occlusion is 1 mechanism for the increase of creatine phosphokinase-MB after percutaneous coronary intervention and is associated with long-term adverse events. We studied 248 patients who underwent brachytherapy for in-stent restenosis with and without side branches, compared levels of creatine phosphokinase-MB with procedural, in-hospital, and long-term clinical outcomes, and found that patients with side branches have increased levels of creatine phosphokinase-MB after percutaneous coronary intervention and higher rates of restenosis, target vessel, and target lesion revascularization at 6-month follow-up.

Effects of percutaneous coronary arterial thrombectomy during acute myocardial infarction on left ventricular remodeling

The benefit of primary angioplasty for acute myocardial infarction (AMI) is limited by the no-reflow phenomenon, resulting in chronic left ventricular (LV) remodeling. The aim of this study was to evaluate the impact of thrombectomy with the Rescue percutaneous thrombectomy catheter on LV function after AMI. We performed a retrospective study comparing conventional angioplasty with the combination of angioplasty and thrombectomy using the Rescue catheter. The study population was comprised of 109 consecutive patients with AMI who underwent angioplasty and thrombectomy and 86 controls treated with conventional angioplasty. Baseline clinical and lesion characteristics were similar in the 2 groups. Postprocedural restoration of normal flow (Thrombolysis In Myocardial Infarction grade 3) was more frequent in the thrombectomy group (82% vs 69%, p = 0.03). No differences were observed in cardiac events, including death, reinfarction, and target vessel revascularization (thrombectomy vs controls, 27% vs 33%; p = 0.44) or changes in ejection fraction (p = 0.22) during 6-month follow-up. The incidence of LV remodeling, defined as an increase in LV end-diastolic volume index of >20%, was significantly lower in the thrombectomy group (22% vs 44%; p = 0.01). Multiple logistic regression analysis revealed that thrombectomy with the Rescue catheter contributed significantly to reduction of both no-reflow and LV remodeling. In the setting of primary angioplasty, adjunctive pretreatment with a rescue catheter reduces the no-reflow phenomenon and protects against LV remodeling.

Six-month angiographic results of primary angioplasty with adjunctive PercuSurge GuardWire device support: Evaluation of the restenotic rate of the target lesion and the fate of the distal balloon occlusion site

Recently, the combination of primary percutaneous coronary intervention (PCI) and adjunctive PercuSurge device support has been reported to be superior to conventional primary PCI in terms of immediate angiographic results. However, there are no data regarding 6-month angiographic results for either the treatment site or the site of the distal protection balloon. The purpose of this study was to address these two issues. Between May and November 2002, a total of 74 patients who had experienced acute myocardial infarction (AMI) underwent either primary PCI (48 patients within 12 hr of AMI) or elective PCI (26 patients with AMI of > 12 hr and < 72 hr) using the PercuSurge device through a transradial approach. The final TIMI 3 flow and myocardial blush grade > or = 2 achieved were 94% and 93%, respectively. Of these patients, three died in the hospital, two died in the third month after discharge, and the remainder of the patients were followed up in our outpatient department for a mean of 13 +/- 2.9 months. Six-month angiographic follow-up was performed in 85.5% (59/69) of patients. The angiographic restenotic rate (defined as > or = 50% restenosis at the target lesion site) was 22.0% (13/59) of patients. However, only 11.9% (7/59) of patients required repeat target vessel revascularization. Moderate obstruction at the site of the distal protection balloon was found in 5.1% (n = 3) of patients during PCI. Six-month angiographic results demonstrated that all three patients had significant stenosis at the site of the distal protection balloon that required PCI. PercuSurge device utilization during PCI in the clinical setting of AMI yielded a substantially higher rate of immediate final TIMI 3 flow in epicardial vessels and increased the integrity of the microvasculature. Combined therapy of PCI with the PercuSurge device appeared to have favorable late angiographic results at the target site. Late significant stenosis occurred at the site of the distal protection balloon if a preexisting moderate or more advanced atherosclerotic lesion was present there.

Formation of a coronary artery aneurysm after inflation of a PercuSurge GuardWire distal protection balloon

Formation of aneurysms in the coronary arteries with the use of the PercuSurge distal protection system has not been reported. We describe a 54-year-old man with acute myocardial infarction who was treated with the PercuSurge system. Angiography performed 2 weeks later revealed an aneurysm in the area of inflation of the distal protection balloon.

Angiographic predictors of left ventricular ejection fraction after successful angioplasty in acute myocardial infarction: An angiographic risk score for use in the catheterization laboratory

We investigated the value of angiographic parameters in patients with successful primary angioplasty using a simple angiographic risk score. In 608 consecutive patients, we assessed the infarct-related artery, antegrade flow before treatment, presence of distal embolization, and myocardial blush grade after coronary angioplasty. LAD-related infarction (OR = 8.4; 3 points), TIMI 0-2 flow before angioplasty (OR = 2.2; 1 point), myocardial blush 0 or 1 (OR = 2.5; 1 point), and distal embolization (OR = 2.2; 1 point) were independent predictors of left ventricular ejection fraction (LVEF) < or = 40% after successful angioplasty. Patients with 0 (minimum) or 1 point have LVEF of 49.5% +/- 8.4% and 30-day mortality of 0.8%. Patients with 2-3 points have LVEF of 44.9% +/- 10.3% and 30-day mortality of 2.8%. Patients with 4 points have LVEF of 38.2% +/- 10.8% and 30-day mortality of 2.7%. Patients with 5-6 (maximum) points have LVEF of 32.0% +/- 9.4% and 30-day mortality of 6.9%. A simple angiographic score predicts LVEF and mortality in patients when leaving the catheterization laboratory after successful primary angioplasty for acute myocardial infarction.

Transradial application of percusurge guardwire device during primary percutaneous intervention of infarct-related artery with high-burden thrombus formation

A large infarct-related artery (IRA), which mostly contains high-burden thrombus formation (HBTF) and lipid pool-like plaque contents, has been suggested to play a pivotal role in the no-reflow phenomenon during primary percutaneous coronary intervention (p-PCI). To reduce the thrombus burden of the IRA using the PercuSurge GuardWire device before intervention may be of crucial importance to preventing no-reflow. The purposes of this study were to test the transradial application (TRA) of this new mechanical device and to determine its impact on prevention of no-reflow during p-PCI. From May to September 2002, the PercuSurge GuardWire device was utilized in 42 consecutive patients with acute myocardial infarction and large IRA (vessel size >or= 3.5 mm with HBTF; group 1). From January to December 2000, p-PCI was performed in large IRA (vessel size >or= 3.5 mm) with HBTF using tranfemoral arterial approach in 101 consecutive patients (group 2). The angiographic and clinical outcomes of the two groups were compared in a chronologically consecutive manner. Successful reperfusion (final TIMI-3 flow) was significantly higher in group 1 than in group 2 patients (95.2% vs. 79.1%; P = 0.005). Moreover, the combined incidence of vascular complications, post-PCI thromboembolisms (defined as a distal embolism and a post-PCI residual thrombus score of >or= 3), and combined 30-day major adverse cardiac events were significantly lower in group 1 than in group 2 patients (all P values < 0.05). In group 1 patients, post-p-PCI myocardial blush (MB) of >or= 2 grades was found to be more than 88.0%. Furthermore, when compared with preintervention, thrombus scores were significantly reduced after aspiration (P = 0.0001), whereas the minimal lumen diameter (P = 0.0001), TIMI flow grade (P = 0.0001), and MB grade (P = 0.0001) had all significantly increased after aspiration using Export Aspiration Catheter. There were no significant differences in corrected TIMI frame count (P = 0.42), TIMI flow grade (P > 0.5), or MB grade (all P values > 0.5) between postaspiration and post-PCI. The TRA of the PercuSurge GuardWire device during primary intervention of large IRA with HBTF was safe and feasible and provided benefits to patients. The initial successful reduction of the thrombus burden with this mechanical device before intervention can be translated into increased final TIMI-3 flow, a combined MB of >or= 2 grades, and fewer final thromboembolic events.

Effect of Adjunctive Tirofiban Therapy on Angiographic and Clinical Outcomes in Patients With ST-segment Elevated Acute Myocardial Infarction Undergoing Primary Stenting

The benefit of primary percutaneous coronary intervention is limited by a 5% to 20% incidence of suboptimal epicardial coronary blood (< or = TIMI-2 flow). Recently, data has demonstrated that when administered in conjunction with primary stenting for the treatment of acute myocardial infarction (AMI), abciximab improves the success rate of the stenting procedure and provides additional clinical benefits. But data on a combination of tirofiban and primary stenting for treatment of ST-segment elevated (ST-se) AMI is unknown. Between May 1999 and September 2000, primary stenting without adjunctive tirofiban therapy was performed in 136 consecutive patients (control group) with ST-se AMI. Between January 2001 and May 2002, we routinely administered tirofiban to 133 consecutive patients (study group) with ST-se AMI before they underwent primary stenting. The angiographic and clinical outcomes of both groups were compared in a chronologically consecutive manner. The overall mortality rate was significantly higher in patients with failed (< or = TIMI-2 flow) than in patients with successful (TIMI-3) reperfusion (20.0% vs 3.5%, P < 0.0001). Univariate analysis demonstrated that there were no significant differences in the successful reperfusion (85.7% vs 84.6%, P = 0.84) or 30-day combined end points - death, recurrent ischemia or reinfarction (8.3% vs 11.0%, P = 0.59) between study and control group patients. Clinical variables were used to statistically analyze potential risk factors for unsuccessful reperfusion (< or = TIMI-2 flow) in the study group patients. Multiple stepwise logistic regression analysis demonstrated that the reference lumen diameter (RLD) of the infarct-related artery (IRA) > or = 3.5 mm (P = 0.0004) and the lesion length of the obstruction > or = 20.0 mm (P = 0.018) were the significant independent predictors of failed normalized coronary blood flow. There were no significant differences in the restenotic rate of IRA (29.2% vs 30.8%, P = 0.9) or mortality rate (1.6% vs 1.6%, P = 1.0) at six-month follow-up. In conclusion, our study demonstrates that primary stenting with adjunctive tirofiban therapy in ST-se AMI did not provide additional benefits in short-term and intermediate-term angiographic and clinical outcomes compared to conventional primary stenting.

Effect of the PercuSurge GuardWire device on the integrity of microvasculature and clinical outcomes during primary transradial coronary intervention in acute myocardial infarction

The present study investigates whether preintervention thrombectomy with a PercuSurge distal balloon protection device can improve final angiographic results compared with adjunctive tirofiban therapy during primary percutaneous coronary intervention (PCI) in large infarct-related arteries (IRAs) (vessel size >/=3.5 mm) with high-burden thrombus formation (HBTF). Results indicate that this mechanical device is superior to adjunctive tirofiban therapy during primary PCI in large IRAs with HBTF in terms of final epicardial flow, microvasculature integrity, and 30-day clinical outcomes.

Intracoronary thrombectomy improves myocardial reperfusion in patients undergoing direct angioplasty for acute myocardial infarction

OBJECTIVES

We sought to evaluate the effects of mechanical thrombectomy on myocardial reperfusion during direct angioplasty for acute myocardial infarction (AMI).

BACKGROUND

Embolization of thrombus and plaque debris may occur during direct angioplasty for AMI. This may lead to distal vessel or side branch occlusion and to obstructions in the microvascular system, resulting in impaired myocardial reperfusion. Mechanical thrombectomy is used to reduce distal embolization.

METHODS

Ninety-two patients with AMI and angiographic evidence of intraluminal thrombus were randomized to either intracoronary thrombectomy followed by stenting or to a conventional strategy of stenting. Thrombectomy was performed using the X-Sizer catheter (EndiCOR Inc., San Clemente, California). Myocardial reperfusion was assessed by myocardial blush and ST resolution.

RESULTS

Postprocedure Thrombolysis in Myocardial Infarction-3 flow was not different between groups (93.5% vs. 95.7%, p = 0.39). Myocardial blush-3 was observed in 71.7% of patients undergoing thrombectomy and in 36.9% of patients undergoing conventional strategy (p = 0.006). ST-segment resolution >or=50% occurred more often in patients undergoing thrombectomy (82.6% vs. 52.2%, p = 0.001). By multivariate analysis, adjunctive thrombectomy was an independent predictor of blush-3 (odds ratio, 3.27; 95% confidence interval, 1.06 to 10.05; p = 0.039).

CONCLUSIONS

Intracoronary thrombectomy as adjunct to stenting during direct angioplasty for AMI improves myocardial reperfusion as assessed by myocardial blush and ST resolution.

Distal protection in native coronary arteries during primary angioplasty in acute myocardial infarction: Single-center experience

Distal embolization of plaque or thrombotic debris is one of the mechanisms involved in the ischemia/reperfusion injury during primary percutaneous intervention for acute occlusion of a native coronary artery. We tested the clinical application of maximal antiplatelet therapy with abciximab combined with one of two different systems of mechanical distal protection: balloon occlusion and aspiration (PercuSurge) in 24 cases and a distal filter (FilterWire Ex) in 10 cases. Feasibility, technical limitations, and pitfalls are described.

Real-time assessment of myocardial perfusion during balloon angioplasty of the left anterior descending coronary artery

Balloon occlusion and release during elective percutaneous coronary intervention (PCI) provides a unique opportunity to study dynamic temporal alterations in myocardial perfusion in a controlled setting. These changes in flow and volume mimic those that occur during presentation with, and successful therapy of, ST-segment elevation acute myocardial infarction (AMI). Eleven patients underwent myocardial contrast echocardiography (MCE) using a continuous infusion of Definity at baseline, during coronary occlusion, and during reactive hyperemia immediately after balloon deflation. Fifty separate flow state sequences were acquired, and off-line analysis was performed to determine myocardial contrast intensity within a region of interest in the distribution of the left anterior descending artery (LAD). A reader blinded to flow state also performed qualitative evaluation (perfusion or lack of perfusion). Quantitative analysis demonstrated significant differences in myocardial contrast intensity by flow state (p = 0.0001 for occlusion vs reperfusion). Qualitative assessment demonstrated a high rate of correct classification (92%). Real-time myocardial perfusion assessment using MCE accurately differentiates coronary occlusion and reactive hyperemia in humans by qualitative and quantitative assessment. This technique may be clinically useful in assessing the efficacy of thrombolytic therapy in ST-segment elevation AMI and in clinical trial assessment of new drugs and devices aimed at limitation of infarct size.

Impact of tirofiban on angiographic morphologic features of high-burden thrombus formation during direct percutaneous coronary intervention and short-term outcomes

BACKGROUND

Recently, we demonstrated that angiographic morphologic features of high-burden thrombus formation are independent predictors of combined slow flow (ie, Thrombolysis in Myocardial Infarction [TIMI] grade 2) and no reflow (ie, </= TIMI grade 1) in the infarct-related artery (IRA) after direct percutaneous coronary intervention (d-PCI) for the treatment of acute myocardial infarction (AMI). Current data have demonstrated that when administered in conjunction with PCI for acute coronary syndrome, platelet glycoprotein IIb/IIIa inhibitors can provide additional clinical benefits. Thus, we hypothesized that after pretreatment with tirofiban, angiographic morphologic features of high-burden thrombus formation would no longer be independent predictors of combined slow flow and no reflow after treatment with d-PCI.

METHODS AND RESULTS

Between January 2001 and April 2002, tirofiban was administered to 210 consecutive patients with ST-segment elevated AMI before coronary angiography was performed, and 84 patients (40.0%) were found to have high-burden thrombus formation in the IRA. The TIMI flow grade of the IRA was assessed immediately after the performance of d-PCI, and the 30-day clinical outcomes were evaluated prospectively. The incidence of restoration of normal coronary flow in the IRA was 83.6%. Three baseline angiographic morphologic features indicating high-burden thrombus formation, including (1) the cutoff pattern of occlusion in the IRA (p = 0.0001), (2) the accumulated thrombus proximal to the occlusion (p = 0.0001), and (3) a reference lumen diameter of the IRA of > or = 4.0 mm (p = 0.001), were independent predictors of combined slow flow and no reflow. In stratified analysis, the rates of slow flow and no reflow after d-PCI rose rapidly as the number of independent predictors increased (0 predictors, 3.8%; 1 predictor, 29.0%; and 2 predictors, 70.6%). The overall 30-day mortality rate was 6.7%. The mortality rate was significantly higher in patients with TIMI flow lower than or equal to grade 2 than in those with TIMI grade 3 flow (15% vs 1.3%, respectively; p = 0.003).

CONCLUSIONS

Tirofiban did not provide additional clinical benefits when administered in conjunction with d-PCI for AMI, even in the subgroup of patients with a high-burden thrombus. Those distinct angiographic morphologic features of high-burden thrombus formation remained as independent predictors of combined slow flow and no reflow after d-PCI, and were independent of the use of tirofiban.

Mechanical prevention of distal embolization during primary angioplasty: safety, feasibility, and impact on myocardial reperfusion

BACKGROUND

Effective myocardial reperfusion after primary percutaneous coronary intervention (PCI) may be limited by distal embolization. We tested the safety, feasibility, and efficacy of the FilterWire-Ex (FW), a distal embolic protection device, as an adjunct to primary PCI.

METHODS AND RESULTS

Fifty-three consecutive patients undergoing primary PCI with FW protection were compared with a matched control group treated by primary PCI alone. Successful FW positioning was obtained in 47 patients (89%) without complications. Histological analysis of the content of the last 13 filters showed multiple embolic debris in all cases. FW use was associated with lower postinterventional corrected TIMI frame count (22+/-14 versus 31+/-19; P=0.005) and higher occurrence of grade 3 myocardial blush (66% versus 36%; P=0.006) and early ST-segment elevation resolution (80% versus 54%; P=0.006). At multivariate analysis, FW use was the only independent predictor of early ST-segment elevation resolution and of grade 3 myocardial blush. FW patients showed lower peak creatine kinase-MB release (236+/-172 versus 333+/-219 ng/mL; P=0.013) and greater improvement at 30 days in left ventricular wall motion score index (-0.30+/-0.19 versus -0.18+/-0.26; P=0.008) and ejection fraction (+7+/-4% versus +4+/-7%; P=0.012).

CONCLUSIONS

FW use during primary PCI is feasible and safe. Distal embolization prevention appears to exert a beneficial effect on markers of myocardial reperfusion and on left ventricular function improvement at 30 days.

Clinical features and outcome of coronary artery aneurysm in patients with acute myocardial infarction undergoing a primary percutaneous coronary intervention

BACKGROUND

While coronary artery aneurysm is an uncommon anatomic disorder and has various forms, its clinical features and outcome and its impact on thrombus formation and the no-reflow phenomenon in the clinical setting of acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (p-PCI) have not been discussed. The purpose of this study was to evaluate whether this anatomic disorder predisposes to a high burden of thrombus formation, and subsequently leads to the no-reflow phenomenon and untoward clinical outcome in patients with AMI undergoing p-PCI.

METHODS AND RESULTS

In our hospital, emergency p-PCI was performed in 924 consecutive patients with AMI between May 1993 and July 2001. Of these 924 patients, 24 patients (2.6%) who had an infarct-related artery (IRA) with aneurysmal dilatation were retrospectively registered and constituted the patient population of this study. Angiographic findings demonstrated that the ectasia type (defined as diffuse dilatation of 50% or more of the length of the IRA) was found most frequently (70%), followed by the fusiform type (20%; defined as a spindle-shaped dilatation in the IRA) and the saccular type (10%; defined as a localized spherical-shaped dilatation in the IRA). The right coronary artery was the most frequently involved vessel (54.2%), followed by the left anterior descending (25.0%) and the left circumflex arteries (20.8%). Coronary angiography revealed that all of these aneurysmal IRA filled with heavy thrombus (indicated as high-burden thrombus formation). The no-reflow phenomenon (defined as <or=TIMI-2 flow) and distal embolization after p-PCI were found in 62.5 and 70.8% of the IRA, respectively. The incidence of cardiogenic shock and the 30-day mortality rate were 25 and 8.3%, respectively. The survival rate was 90.9% (20/22) during a mean follow-up of 19 +/- 30 months.

CONCLUSIONS

While aneurysmal dilatation of an IRA is an uncommon angiographic finding in the clinical setting of AMI, it is frequently associated with high-burden thrombus formation and has a significantly lower incidence of successful reperfusion. However, the long-term survival of these patients is excellent.

Revascularization of a thrombosed aortopulmonary shunt with the use of the AngioJet thrombectomy system

We report the use of the AngioJet F140 rheolytic catheter to recannalize an acutely thrombosed aortopulmonary shunt in a 21-year-old female with palliated, complex congenital heart disease. After extracting the thrombus that filled the entire length of the shunt, three stents were placed at sites where the lumen was compromised by distortion or thrombus. Unobstructed flow was restored to the left pulmonary artery that persisted at 1-year follow-up.

Clinical features and outcome of patients with direct percutaneous coronary intervention for acute myocardial infarction resulting from left circumflex artery occlusion

BACKGROUND

Little is known about the clinical features and outcome of patients with left circumflex artery (LCX) infarct-related acute myocardial infarction (AMI). This study was conducted to investigate the clinical features and outcome of patients who underwent direct percutaneous coronary intervention (d-PCI) for AMI caused by LCX occlusion, and to discover prognostic determinants in this clinical setting.

METHODS AND RESULTS

Between May 1993 and October 2000, a total of 819 patients with AMI underwent d-PCI in our hospital. Sixty-seven patients (8.2%) who had LCX infarct-related AMI constituted the population of this study. Ten of 67 patients (14.9%) were in cardiogenic shock. Angiographic findings demonstrated that the incidences of triple-vessel disease, reference lumen diameter (RLD) of the LCX > or = 4.0 mm, and LCX as the dominant artery in these patients were 26.9%, 22.4%, and 34.3%, respectively. Sixteen patients (23.9%) had unsuccessful reperfusion (defined as Thrombolysis in Myocardial Infarction flow < or = 2). Univariate analysis showed that dominant LCX, RLD of the LCX > or = 4.0 mm, cardiogenic shock, precordial ST-segment depression, and complete atrioventricular block were significantly related to unsuccessful reperfusion. Multiple stepwise logistic regression analysis demonstrated that dominant LCX and cardiogenic shock were significant independent predictors of unsuccessful reperfusion. The 30-day mortality rate in the 67 patients was 14.9%. Univariate analysis demonstrated that triple-vessel disease, dominant LCX, cardiogenic shock, poor left ventricular ejection fraction, and unsuccessful reperfusion were significantly associated with 30-day mortality. By multiple stepwise logistic regression analysis, dominant LCX, cardiogenic shock, and triple-vessel disease were significant independent predictors of increased 30-day mortality.

CONCLUSIONS

LCX infarct-related AMI has its unique clinical features. The presence of dominant LCX and cardiogenic shock were independent determinants of unsuccessful reperfusion, and the presence of dominant LCX, cardiogenic shock, and triple-vessel disease were independent determinants of increased 30-day mortality in this clinical setting.

Export aspiration catheter thrombosuction before actual angioplasty in primary coronary intervention for acute myocardial infarction

Primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) in lesions with a large thrombus load increases the procedural complication rate. We describe a thrombus reduction technique in this setting using the Export aspiration catheter (EAC) for primary thrombosuction before actual angioplasty. The EAC is a component of the GuardWire Plus system (PercuSurge, Sunnyvale, CA), which was originally developed for emboli containment in saphenous vein graft and peripheral vessel interventions. Primary EAC thrombosuction was performed successfully in 12 patients undergoing primary PCI, and gross thrombi were obtained from 9 patients (75%). After definitive treatment with balloon angioplasty and/or stenting, TIMI 3 flow was restored in all target vessels. There was no angiographic evidence of distal branch loss or vessel injury. No major procedural or in-hospital complication occurred in any patients. This primary EAC thrombosuction technique may offer a new, potentially effective method for thrombus burden reduction in treating AMI patients.

Coronary artery saddle embolus and myocardial infarction in a patient with prosthetic mitral valve

Coronary embolism is a rare cause of transmural myocardial infarction. A 58-year old female with mechanical mitral valve prosthesis and chronic atrial fibrillation who presented with anterolateral myocardial infraction is described. The etiologies, diagnosis, treatment dilemma and various management options are discussed.

Coronary artery "pseudothrombus" due to collateral flow artifact distal to left circumflex coronary stenosis

Since the complexity, morbidity, and costs of coronary interventions are increased when coronary thrombus is present, identification of the cause of an angiographic filling defect is potentially important. We present a case report and review our experience with a flow artifact that mimicked thrombus ("pseudothrombus") in the setting of a severe proximal stenosis in the left circumflex coronary artery.