Thrombosis within the left anterior descending coronary artery and left ventricle after high-dose nitrous oxide use.

We present a man in his 30s with acute anterior myocardial infarction due to thrombotic occlusion of the left anterior descending artery and subsequent left ventricular thrombus formation after high-dose recreational use of nitrous oxide (N2O). Initial questioning for use of illicit substances was negative, but low vitamin B12 levels and severely elevated homocysteine levels prompted us to interrogate for the use of laughing gas. On questioning, the patient admitted to have used this substance, which he presumed to be innocent. Neither percutaneous coronary intervention with balloon dilatation nor intravenous glycoprotein IIb/IIIa receptor antagonist, nor continuous use of anticoagulation and double antiplatelet therapy resulted in thrombus resolution. Due to a severely reduced left ventricular function, despite 3 months on heart failure therapy, the patient is being counselled for intracardiac defibrillator implantation. We conclude that N2O, notably when consumed in conjunction with other proatherogenic substances, is associated with thrombosis: a relation possibly mediated by severe hyperhomocysteinaemia.

Efficacy of Direct Acting Oral Anticoagulant Drugs in Treatment of Left Atrial Appendage Thrombus in Patients With Atrial Fibrillation.

Direct acting oral anticoagulants (DOACs) are increasingly used for thromboembolic prophylaxis in patients with atrial fibrillation (AF). However, there is limited data to evaluate the use of DOACs for the treatment of pre-existing left atrial appendage thrombus. We aimed to determine the efficacy of DOACs in treatment of left atrial appendage (LAA) thrombus utilizing transesophageal echocardiographic (TEE) and clinical outcomes. In this single-center study, we identified 33 patients that were treated for LAA thrombus with DOAC. Eighteen were treated with apixaban, 10 with dabigatran, and 5 with rivaroxaban. The primary endpoint was defined as resolution of LAA thrombus (in patients undergoing TEE), or death, major bleeding requiring transfusion, intracranial hemorrhage, ischemic stroke, or peripheral embolization. In this study, 15 of the 16 patients treated with DOACs who underwent follow-up TEE had resolution of LAA thrombus, with a mean duration of 112 days. Of the 15 patients who achieved resolution of the LAA thrombus, 14 had resolution by their first follow-up TEE. In the 17 patients without a follow-up TEE, 1 died of a retroperitoneal bleed (28 days after DOAC initiation), and 1 suffered an ischemic stroke (484 days after DOAC initiation). In general, patients without a follow-up TEE were older and had more co-morbidities. Although these results are descriptive and limited in number of patients, we believe this is ample evidence that DOACs are relatively safe and efficacious in treatment of patients with AF and concomitant LAA thrombus.

Aspiration thrombectomy and intracoronary tirofiban via GuideLiner® catheter for a thrombosed aneurysmal vessel.

A 52-year-old Asian male with no traditional risk factors for coronary artery disease presented with acute coronary syndrome. Coronary angiography showed complete thrombotic occlusion of the left circumflex with a large thrombus burden in the setting of diffuse aneurysmal enlargement of the coronary arteries consistent with antecedent Kawasaki disease. Manual thrombectomy with adjunctive intracoronary tirofiban was performed utilizing the GuideLiner catheter® (Vascular Solutions, Inc., MN, USA). Stent implantation was deferred. Follow-up imaging 48 h later showed preserved coronary flow and decreased thrombus burden. The GuideLiner catheter, a monorail guiding device, served a novel role in thrombus aspiration and intracoronary medication delivery.

The association of the coronary thrombus burden with all-cause mortality and major cardiac events in ST-segment elevation myocardial infarction patients treated with tirofiban.

BACKGROUND: The aim of this study was to investigate the association of the coronary thrombus burden with all-cause mortality and major adverse cardiac events (MACE) in ST-segment elevation myocardial infarction (STEMI) patients treated with 'in-cath lab' (downstream) high-dose bolus tirofiban. METHODS: This study included 2452 patients with STEMI treated with a primary percutaneous coronary intervention. All glycoprotein IIb/IIIa receptor inhibitor (GPI) (tirofiban) infusions were started in the catheterization laboratory according to the coronary thrombus burden; tirofiban was not administered to patients who did not have coronary thrombus burden. All patients with small, moderate, or large thrombus burden received tirofiban therapy. The primary study endpoint was the incidence of all-cause mortality. The secondary study endpoints were major bleeding and MACE, which included all-cause death, nonfatal acute coronary syndrome, and target lesion revascularization. RESULTS: The patients were followed up for a mean period of 28.3±10.4 months. The groups showed similar in-hospital and long-term event rates (MACE, major bleeding, and all-cause mortality). The 3-year Kaplan-Meier overall survivals for no thrombus, small thrombus, moderate thrombus, and large thrombus were 91.9, 92.6, 92.3, and 89.5%, respectively. CONCLUSION: Despite the fact that the large coronary thrombus was found to be a predictor of MACE and mortality in many previous studies, we found that the large thrombus was not associated with MACE or in-hospital mortality or long-term mortality. This can be an effect of downstream GPI therapy. We suggest the use of downstream GPI therapy for STEMI patients with large coronary thrombus without an increased risk of bleeding.

Intracardiac echocardiography for detection of thrombus in the left atrial appendage: comparison with transesophageal echocardiography in patients undergoing ablation for atrial fibrillation: the Action-Ice I Study.

BACKGROUND: Transesophageal echocardiography (TEE) is the gold standard for the exclusion of thrombi in the left atrial appendage (LAA) before ablation for atrial fibrillation. Intracardiac echocardiography (ICE) is used to assist atrial fibrillation ablation; however, it can also be used for LAA imaging. The aim of our study was to determine whether ICE could replace TEE and to identify the optimal ICE placement for LAA visualization. METHODS AND RESULTS: Seventy-six consecutive patients (56 men; mean age, 55±9.6 years) scheduled for atrial fibrillation ablation underwent TEE before the procedure and LAA assessment by ICE. An 8F AcuNav probe was introduced into right atrium, pulmonary artery, and coronary sinus. LAA structure was analyzed by the echocardiographer and electrophysiologist who were blinded to the results of TEE. ICE probe was positioned in the right atrium in all patients, in the pulmonary artery in 64 of 74 (86%) patients, and in the coronary sinus in 49 of 74 (66%) patients. The LAA was properly visualized in 56 of 64 (87.5%) patients from the pulmonary artery versus 13 of 49 (26%) patients from the coronary sinus (P<0.001). From the right atrium, the whole LAA cavity could not be seen in any patient. In those patients in whom LAA was visualized properly by ICE, a perfect agreement between ICE and TEE was obtained (both techniques detected LAA thrombus in 2 patients and excluded LAA thrombus in the remaining patients). CONCLUSIONS: ICE can be used safely and effectively for the evaluation of LAA in patients undergoing atrial fibrillation ablation. ICE imaging from pulmonary artery is accurate for LAA visualization. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01371279.

[Acute myocardial infarction with simultaneous occlusions of two coronary arteries in a 44 year-old man]. / Zawal serca u 44-letniego chorego spowodowany jednoczesnym zamknieciem dwóch tetnic wiencowych.

Simultaneous thrombosis of multiple epicardial coronary arteries is an uncommon clinical finding in ST-segment elevation myocardial infarction (STEMI). We describe a 44 year-old male present with STEMI who was found to have simultaneously occluded two epicardial arteries. There is many clinical states that can lead to multiple thrombosis i.e. essential trombocytosis, hiperhomocysteinaemia, depletion of antitrombin III, cocaine abuse etc. In this particular case L-arginin supplementation and association with thrombosis or atherosclerosis progression is discussed.

Coronary artery aneurysm and thrombosis following chronic ephedra use.

Ephedra, also known as Ma Huang, was commonly used to enhance athletic performance, "fat burning", and weight loss before its removal from the United States in April 2004 due to acute adverse health reactions including lethal arrhythmias, stroke, vasoconstriction, and myocardial infarction. We report the case of a 29-year-old patient with acute myocardial infarction, secondary to coronary artery aneurysms and thrombosis who reported use of Ma Huang, Xenadrine(r)RFA, and Hydroxycut at recommended dosages for a combined total of approximately 2 years. Other causes of coronary artery aneurysm and hypercoagulability were ruled out. Our case exemplifies the long-term (as opposed to acute) danger of ephedrine products and the first case of coronary artery aneurysm associated with its use.

STEMI in a 24-year-old man after use of a synephrine-containing dietary supplement: a case report and review of the literature.

Billions of dollars are spent annually in the United States in the largely unregulated market of dietary supplements. Many of these supplements are marketed as weight-loss and athletic-performance-enhancement products. The association of various ephedra-containing products with adverse cardiovascular events has led to a ban on the sale of these products by the U.S. Food and Drug Administration. The result has been the emergence of new formulations marketed for weight loss and athletic-performance enhancement that are "ephedra-free" but contain other sympathomimetic substances, the safety of which has not been established. We present the case of a previously healthy 24-year-old man who presented with an ST-segment-elevation myocardial infarction (STEMI) within hours of taking the ephedra-free product Nutrex Lipo-6x. Emergent coronary angiography revealed the presence of extensive, diffuse thrombus in the left anterior descending coronary artery. The patient had no risk factors for coronary artery disease or myocardial infarction; this includes the absence of a hypercoagulable state and the absence of a history of illicit drug use. This case of STEMI--associated as it is with the use of a synephrine-containing product by a person without risk factors for coronary artery disease--is to our knowledge the 1st reported in the literature. We discuss the patient's evaluation and clinical course, and we review the literature with respect to synephrine-containing dietary supplements. On the basis of synephrine's chemical composition and mechanism of action, we propose a direct association between this patient's use of Nutrex Lipo-6x and his STEMI.

[Research on relationship between coronary lesion and blood stasis syndrome based on coronary angiography].

OBJECTIVE: To explore the relationship between blood stasis (BS) syndrome and coronary lesion in patients with coronary heart disease (CHD). METHODS: Syndrome types of 500 patients collected from multiple centers whose diagnosis of CHD confirmed by coronary angiography were differentiated. And the relationship between BS syndrome, its subtypes, and coronary lesion (affected branches, degree of constriction) were analyzed. RESULTS: The affected branches of coronary artery in patients of BS syndrome was 2.28 +/- 0.28, while that in the non-BS syndrome patients was 2.07 +/- 0.86, showing significant difference between them (P < 0.05); as compared to patients of non-BS syndrome, the coronary lesions in patients of BS syndrome were mostly multi-vascular, and of more severe degree (P < 0.05). In patients of various BS syndrome subtypes, the average number of affected coronary branches in patients of yang-deficiency subtype was 2.58 +/- 0.65, which was significantly more than the number in patients of other BS syndrome subtypes. The constriction degree of coronary lesions in patients of yang-deficiency BS syndrome subtype were mostly severe or moderate, and single branch lesion was rarely seen, as compared with those in patients of phlegm-stasis obstruction subtype, the difference was significant (P < 0.05). The corresponding correlative analysis showed that close correlation was found between yang-deficiency subtype of BS syndrome and severe coronary constriction with the correlation distance of 0.1899. CONCLUSION: Relationship between BS syndrome and coronary lesion (its number of branches and degree of constriction) truly exists to a certain extent.

Combination of a high bolus dose of tirofiban with half-dose thrombolytics for the treatment of subacute stent thrombosis.

Acute stent thrombosis is rare and it is usually related to complications during the procedure. Subacute thrombosis is far more common and is associated with a high incidence of acute myocardial infarction and death. Restoration of flow by thrombolysis, emergency bypass surgery or emergency percutaneous transluminal coronary angioplasty (PTCA) has had only limited success with respect to myocardial salvage. We report the case of a patient who suffered from recurrent subacute stent thrombosis, in whom administration of tirofiban at high-dose bolus in association with a half dose of recombinant tissue plasminogen activator succeeded in restoring normal myocardial flow and stable clinical condition.

Adjunctive platelet glycoprotein IIb/IIIa receptor inhibition with tirofiban before primary angioplasty improves angiographic outcomes: results of the TIrofiban Given in the Emergency Room before Primary Angioplasty (TIGER-PA) pilot trial.

BACKGROUND: Previous work has suggested that platelet glycoprotein IIb/IIIa receptor blockade may confer benefit in the treatment of acute myocardial infarction. The TIGER-PA pilot trial was a single-center randomized study to evaluate the safety, feasibility, and utility of early tirofiban administration before planned primary angioplasty in patients presenting with acute myocardial infarction. METHODS AND RESULTS: A total of 100 patients presenting with acute myocardial infarction were randomized to either early administration of tirofiban in the emergency room or later administration in the catheterization laboratory. The primary outcome measures were initial TIMI grade flow, corrected TIMI frame counts, and TIMI grade myocardial perfusion ("blush"). Thirty-day major adverse cardiac events were also assessed. Angiographic outcomes demonstrate a significant improvement in initial TIMI grade flow, corrected TIMI frame counts, and TIMI grade myocardial perfusion when patients are given tirofiban in the emergency room before primary angioplasty. The rate of 30-day major adverse cardiac events suggests that early administration may be beneficial. CONCLUSIONS: This pilot study suggests that early administration of tirofiban improves angiographic outcomes and is safe and feasible in patients undergoing primary angioplasty for acute myocardial infarction.

Comparison of a synthetic antithrombin III-binding pentasaccharide and standard heparin as an adjunct to coronary thrombolysis.

The effects on alteplase-induced thrombolysis of the synthetic ATIII-binding pentasaccharide SR90107A/ORG 31540 (synthetic pentasaccharide, SP) and of standard heparin (SH) were compared in a copper coil model of coronary artery thrombosis in 6 groups of 10 dogs. After 1 h of occlusion, all animals received intravenously alteplase and aspirin, and were randomly assigned to a 2 h infusion of either saline, or one of two doses of SH (100 IU/kg bolus plus 50 IU/kg/h infusion, or 200 IU/kg bolus plus 100 IU/kg/h infusion), or one of three doses of SP (100 nmol/kg bolus plus 50 nmol/kg/h infusion, 200 nmol/kg bolus plus 100 nmol/kg/h infusion, or 400 nmol/kg bolus plus 200 nmol/kg/h infusion). Coronary angiography was performed every 10 min for 4 h. Appropriate doses of SP and SH enhanced alteplase-induced thrombolysis to a similar extent. In contrast, SP was devoid of any anti-IIa activity or aPTT prolongation.

Local treatment with an antithrombotic drug reduces thrombus size in coronary and peripheral thrombosed arteries.

Since the treatment of thrombotic disease by antithrombotic drugs may be associated with bleeding complications, a local delivery technique for administration of the drug may be useful. The efficacy of low-dose local delivery of an antithrombotic drug on thrombosis was investigated in 73 dogs. The antithrombotic drug (heparin, 25 U/kg, antithrombin: argatroban, 0.05 mg/kg, or defibrinogenating agent: batroxobin, 0.05 U/kg) was infused locally to a 1-h-old thrombus, and no drug was given in controls. The effect of the local delivery on the thrombus was evaluated. Low- and high-dose systemic drug delivery was also evaluated. The mean reduction in thrombotic coronary stenosis observed by angiography was 30.3% with argatroban, 22% with heparin, and 20.8% with batroxobin (P < 0.005 vs controls). Systemic delivery of low-dose heparin or argatroban did not induce any change in thrombus size. With high-dose systemic drug delivery (heparin 250 U/kg, argatroban 0.5 mg/kg), the mean reduction of thrombotic stenosis was 15.2% with heparin and 32.8% with argatroban (P < 0.005 vs controls). In the iliac arterial thrombosis, after local delivery of the drugs, the mean reduction of thrombotic stenosis observed by angiography was 24.4% in the argatroban group, and 19.2% in the heparin group (P < 0.05 vs controls, respectively). With high-dose systemic heparin delivery, the mean reduction of the thrombotic stenosis was 13.2% (P < 0.01 vs control). Angioscopy also demonstrated a similar trend. The high-dose drug delivery reduced systemic coagulability. Thus, local delivery of an antithrombotic agent can reduce the thrombus size in the coronary and iliac arteries without having any significant influence on coagulability.

Coronary thrombolysis. Comparative effects of intracoronary administration of recombinant tissue plasminogen activator and urokinase.

We employed a canine model of coronary thrombosis, induced by injection of radioactive blood clot, via a catheter placed in the left anterior descending coronary artery, to compare effects of intracoronary administration of recombinant tissue plasminogen activator (rtPA) and urokinase (UK) on rate and extent of coronary thrombolysis. Two doses of UK, 15,000 U/kg (UK15) and 30,000 U/kg (UK30) and two doses of rtPA, 0.25 mg/kg (rtPA.25) and 0.75 mg/kg (rtPA.75) were given. Drugs were infused over 45 min. Compared with the other regimens, rate and extent of coronary thrombolysis were significantly increased with rtPA.75. Also, despite a much higher dose of UK, coronary thrombolysis was similar with UK30 and rtPA.25. Compared with UK15, rate and extent of coronary thrombolysis were increased with rtPA.25. These results indicate that intracoronary administration of rtPA is superior to intracoronary UK in inducing thrombolysis.

[Possibilities for imaging intracardiac thrombi with indium 111 thrombocyte scintigraphy]. / Darstellungsmöglichkeit intrakardialer Thromben durch die Indium-111-Thrombozytenszintigraphie.

Intracardiac thrombi can be localized and quantified by indium-111-labelling of thrombocytes with a high sensitivity and specificity. The scintigraphic procedure has a complementary evidence to echocardiography. Scintigraphy shows activity and age of thrombosis, whereas echocardiography seems to be superior in determination of mass and localization. In older thrombi scintigraphy fails because of organisation and endothelialization of the thrombus surface. For the reason of determination of the age of an intraventricular thrombus this method might have an increasing acceptance.

[Imaging of intra-cardiac thrombi with indium 111 scintigraphy]. / Darstellbarkeit intrakardialer Thromben durch die Indium-111-Szintigraphie.

Intracardiac thrombi can be localized and quantified by Indium-111-labelling of thrombocytes with a high sensitivity and specificity. The scintigraphic procedure has a complementary evidence to echocardiography. Scintigraphy shows activity and age of thrombosis, whereas echocardiography seems to be superior in determination of mass and localization. In older thrombi scintigraphy fails because of organisation and endothelialization of the thrombus surface. For the reason of determination of the age of an intraventricular thrombus this method might have an increasing acceptance.

Angiographic morphology and response to therapy in unstable angina.

The coronary anatomy of 69 patients with unstable angina, subgrouped according to response to medical therapy, was investigated. All patients received oral treatment with nitrates, calcium antagonists, and beta-blocking agents. When combined oral treatment was not effective, an intravenous infusion of nitrates (10-100 micrograms/min) was subsequently administered. Coronary arteriography was performed within hours (14 +/- 9 h) from the last episode of chest pain in 28 patients refractory to medical treatment, while in 41 patients who became asymptomatic during medical therapy, angiography was performed after an observation period of several days (8 +/- 6 days). On angiography, the nonresponder group was characterized by a prevalence of eccentric and multiple lesions, and by a 46% incidence of thrombi (p less than 0.001). Recurrent symptoms requiring emergency bypass operation were common in this group. In patients responsive to medical treatment, a high percentage of concentric lesions (37%) and totally occluded (34%) coronary arteries was found (p less than 0.05). No infarcts and low rate of recurrent angina were noted in these patients during hospitalization. In conclusion, the finding of intracoronary thrombotic material and eccentric or multiple lesions can be an accurate markers of the active phase of the disease, while "silent" occlusion of the involved vessel may be accompanied by relief of symptoms during medical therapy.