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Percutaneous Transluminal Coronary Angioplasty (percutaneou + transluminal_coronary_angioplasty)
Selected AbstractsLong-term clopidogrel administration following severe coronary injury reduces proliferation and inflammation via inhibition of nuclear factor-kappaB and activator protein 1 activation in pigsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2009K. Pels ABSTRACT Background, The optimal duration of clopidogrel treatment following percutaneous coronary intervention (PCI) and the patient population that would benefit most are still unknown. In a porcine coronary injury model, we tested two different durations of clopidogrel treatment on severely or moderately injured arteries and examined the arterial response to injury. To understand the molecular mechanism, we also investigated the effects on transcription factors nuclear factor-kappaB (NF-,B) and activator protein 1 (AP-1). Materials and methods, In 24 cross-bred pigs, one coronary artery was only moderately injured by percutaneous transluminal coronary angioplasty (PTCA) and one coronary artery was severely injured by PTCA and subsequent beta-irradiation (Brachy group). Animals received 325 mg aspirin daily for 3 months and 75 mg clopidogrel daily for either 28 days [short-term (ST) clopidogrel group] or 3 months [long-term (LT) clopidogrel group]. Results, After 3 months, the number of proliferating cells per cross-section differed significantly between ST and LT in both injury groups (PTCAST 90·2 ± 10·3 vs. PTCALT 19·2 ± 4·7, P < 0·05; BrachyST 35·8 ± 8·4 vs. BrachyLT 7·5 ± 2·0, P < 0·05). Similar results were seen for inflammatory cells (CD3+ cells): PTCAST 23·5 ± 3·55 vs. PTCALT 4·67 ± 0·92, P < 0·05; BrachyST 83·17 ± 11·17 vs. BrachyLT 20 ± 4·82, P < 0·05). Long-term administration also reduced the activity of NF-,B and AP-1 by 62,64% and 42,58%, respectively. However, the effects of different durations of clopidogrel administration on artery dimensions were not statistically significant. Conclusions, Regarding inflammation and transcription factor activity at the PCI site, long-term clopidogrel administration is superior to short-term administration, especially in severely injured arteries. Transferring our results to the human situation, patients with more severely diseased arteries may benefit from a prolonged clopidogrel medication after PCI. [source] Brain natriuretic peptide in the prediction of recurrence of angina pectorisEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2 2004H. Takase Abstract Background, Circulating levels of brain natriuretic peptide (BNP) provide prognostic information for patients with heart failure, but little is known about its prognostic usefulness in patients with stable angina pectoris. We investigated whether BNP could be used as a marker for the prediction of anginal recurrence after successful treatment. Design, Brain natriuretic peptide levels of 77 patients with stable angina pectoris were measured at enrolment and after confirmation of successful treatment (i.e. no anginal attack for at least 6 months: chronic phase) with percutaneous transluminal coronary angioplasty and/or conventional medication. Then, we prospectively followed them up for 25·9 ± 1·4 months, with the endpoint being a recurrence of anginal attacks. Results, An anginal attack recurred in seven patients. In patients without recurrence, BNP levels in the chronic phase (21 ± 12 [median ± median absolute deviation] pg mL,1) were lower than those measured at enrolment (46 ± 25 pg mL,1, P < 0·0001), whereas the levels in patients with recurrence increased during the same period (from 36 ± 16 to 72 ± 42 pg mL,1, P < 0·05). A univariate analysis revealed that the BNP level measured in the chronic phase was the significant predictor of future anginal recurrence. Analysis of the receiver operating characteristic curve indicated that the cutoff level of BNP in the chronic phase was 68 pg mL,1. The Kaplan-Meier method revealed that the incidence of anginal recurrence was higher in patients with higher (71·4%) than lower levels of BNP (2·9%; P < 0·0001). Conclusions, Measurement of BNP levels after successful therapy is clinically useful for the prediction of recurrence of anginal attacks in patients with angina pectoris. [source] Effects of percutaneous transluminal coronary angioplasty on coronary adenosine concentrations in humansEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2 2000Paganelli Background Even minimal amounts of adenosine is released during myocardial ischemia. Its role in coronary blood flow has been extensively studied, but little is known about its behaviour during percutaneous transluminal angioplasty (PTCA) in man. Material and methods Using in situ samples the aim of this study was to evaluate adenosine plasma concentration before and after PTCA. Ten patients (8 men and 2 women, mean age 65 ± 9 years) with a single stenosis of the left anterior descending coronary artery (LAD) of at least 70% and 10 healthy volunteers (4 men and 6 women, mean age 55 ± 9 years) were included in the study. Results and discussion We found that there is a close relationship between the degree of the stenosis and the adenosine concentrations in the great cardiac vein and in the LAD, and that after PTCA there is a drop in adenosine concentration downstream from the stenosis. This study confirms the crucial role of adenosine in coronary blood flow control. [source] The influence of economic incentives and regulatory factors on the adoption of treatment technologies: a case study of technologies used to treat heart attacksHEALTH ECONOMICS, Issue 10 2009Mickael Bech Abstract The Technological Change in Health Care Research Network collected unique patient-level data on three procedures for treatment of heart attack patients (catheterization, coronary artery bypass grafts and percutaneous transluminal coronary angioplasty) for 17 countries over a 15-year period to examine the impact of economic and institutional factors on technology adoption. Specific institutional factors are shown to be important to the uptake of these technologies. Health-care systems characterized as public contract systems and reimbursement systems have higher adoption rates than public-integrated health-care systems. Central control of funding of investments is negatively associated with adoption rates and the impact is of the same magnitude as the overall health-care system classification. GDP per capita also has a strong role in initial adoption. The impact of income and institutional characteristics on the utilization rates of the three procedures diminishes over time. Copyright © 2008 John Wiley & Sons, Ltd. [source] The mechanisms of coronary restenosis: insights from experimental modelsINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 2 2000Gordon A.A. Ferns Since its introduction into clinical practice, more than 20 years ago, percutaneous transluminal coronary angioplasty (PTCA) has proven to be an effective, minimally invasive alternative to coronary artery bypass grafting (CABG). During this time there have been great improvements in the design of balloon catheters, operative procedures and adjuvant drug therapy, and this has resulted in low rates of primary failure and short-term complications. However, the potential benefits of angioplasty are diminished by the high rate of recurrent disease. Up to 40% of patients undergoing angioplasty develop clinically significant restenosis within a year of the procedure. Although the deployment of endovascular stents at the time of angioplasty improves the short-term outcome, ,in-stent' stenosis remains an enduring problem. In order to gain an insight into the mechanisms of restenosis, several experimental models of angioplasty have been developed. These have been used together with the tools provided by recent advances in molecular biology and catheter design to investigate restenosis in detail. It is now possible to deliver highly specific molecular antagonists, such as antisense gene sequences, to the site of injury. The knowledge provided by these studies may ultimately lead to novel forms of intervention. The present review is a synopsis of our current understanding of the pathological mechanisms of restenosis. [source] Iatrogenic Forearm Compartment Syndrome in a Cardiac Intensive Care Unit Induced by Brachial Artery Puncture and Acute AnticoagulationJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 2 2002M.H.A, SHAY SHABAT M.D. A previously healthy patient developed late compartment syndrome in the cardiac intensive care unit after a brachial artery puncture due to acute heparinization after successful percutaneous transluminal coronary angioplasty (PTCA) and stent implantation. The cardiologists recognized the problem and immediately consulted an orthopedic surgeon, who promptly performed surgery. The latter consisted of decompression and fasciotomy. The patient recovered excellent hand function without any neurologic or muscular deficits. Knowledge and understanding of the clinical aspects of this complication are crucial in this devastating syndrome. [source] Identification of Hemodynamically Significant Restenosis after Percutaneous Transluminal Coronary Angioplasty in Acute Myocardial Infarction by Transesophageal Dobutamine Stress Echocardiography and Comparison with Myocardial Single Photon Emission Computed TomographyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2001STEPHAN ROSENKRANZ M.D. Background: Beside thrombolysis, percutaneous transluminal coronary angioplasty (PTCA) has become a well-established treatment for acute myocardial infarction. However, restenosis occurs in approximately 15%-40 % of patients. Despite a frequently occurring infarct-related regional systolic dysfunction at rest, the identification of hemodynamically relevant restenosis seems important in terms of risk stratification, adequate treatment, and possible improvement of prognosis in these patients. This study was designed to assess the role of transesophageal dobutamine stress echocardiography and myocardial scintigraphy for identification of hemodynamically significant restenosis after PTCA for acute myocardial infarction. Methods: Multiplane transesophageal stress echocardiography (dobutamine 5, 10, 20, 30, and 40 ,g/kg per min) studies and myocardial single photon emission computed tomography (SPECT) studies were performed in 40 patients, all of whom underwent PTCA in the setting of acute myocardial infarction , 4 months prior to the test. Repeated coronary angiography was performed in all study patients who showed stress-induced perfusion defects or wall-motion abnormalities, or both. Results: Significant restenosis (, 50%) was angiographically found in 15 (37.5%) of 40 patients. Of these 15 patients, transesophageal dobutamine stress echocardiography identified restenosis in 12 (80%) and myocardial SPECT in 14 (93%), yielding diagnostic agreement in 70% of patients. Echocardiographic detection of restenosis was based mainly on a biphasic response to increasing doses of dobutamine. Sensitivity and specificity for identification of hemodynamically relevant restenosis in individual patients was 80% and 92%, respectively for dobutamine stress echocardiography versus 93% and 68% for myocardial SPECT. Conclusions: Both transesophageal dobutamine stress echocardiography and myocardial SPECT were highly sensitive in identifying significant restenosis after PTCA for acute myocardial infarction. Therefore, either test, as a single diagnostic tool or especially if performed together, are clinically valuable alternatives to coronary angiography for the detection of restenosis after PTCA for acute myocardial infarction. [source] Lipid metabolism and occurrence of post-percutaneous transluminal coronary angioplasty restenosis: role of cholesteryl ester transfer protein and paraoxonase/arylesteraseJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2003R. Y. L. Zee Summary., Plasma lipid metabolic and transfer processes have recently been suggested to play an important role in the development of early restenosis, a major complication of percutaneous transluminal coronary angioplasty (PTCA); in particular, the common variants of genes for cholesteryl ester transfer protein (CETP) and paraoxonase (PONA) have been implicated. We had the opportunity to investigate this question in a large, prospective cohort characterized by quantitative coronary angiography in all subjects. The CETP-TaqIB (intron 1), CETP-MspI (intron 8), and PONA-AlwI (exon 2) polymorphisms were characterized in a cohort of 779 patients of whom 342 (,cases') had developed restenosis (as defined by >,50% loss of lumen compared with immediate postprocedure results) at repeat angiography at 6 months post PTCA. Selected frequencies for CETP B1 and B2 alleles (absence/presence of TaqIB site) were 0.65 and 0.35 (cases) and 0.65 and 0.35 (controls), respectively; frequencies for CETP M1 and M2 alleles (absence/presence of MspI site) were 0.20 and 0.80 (cases), 0.21 and 0.79 (controls), respectively; frequencies for PONA A and B alleles (absence/presence of AlwI site) were 0.73 and 0.27 (cases), 0.72 and 0.28 (controls), respectively. All observed genotype frequencies were in Hardy,Weinberg equilibrium. There was no evidence for gene,gene interaction, or an association between genotype and restenosis or degree of lumen loss (adjusted for covariates). Our data, collected in the largest study of its kind so far, indicate that the common variants for CETP and PONA are not associated with incidence of restenosis after PTCA, and are therefore not useful markers for risk assessment. [source] Fluorescence spectroscopic analysis of circulating platelet activation during coronary angioplastyLASERS IN SURGERY AND MEDICINE, Issue 5 2001Alexander Christov PhD Abstract Background and Objective Platelet activation during percutaneous transluminal coronary angioplasty (PTCA) initiates thrombus formation and plaque regrowth at sites of arterial injury, limiting procedure efficacy. We have developed a simple assay for circulating platelet activation based on fluorescence analysis of membrane fluidity and intracellular calcium concentration and light scattering analysis of platelet aggregation. Study Design/Materials and Methods Platelet activation state was measured in 45 patients undergoing angioplasty, before and after treatment with platelet inhibitors. Results PTCA alone produced a decrease in pyrene dimer formation (P0.0083) and an increase in light scattering at 650 nm (P0.0128). Treatment with ADP and GPIIb/IIIa receptor antagonists reduced PTCA induced changes in pyrene dimer formation. An unexpected decrease in pyrene dimer formation (P0.05) was detected when the GPIIb/IIIa receptor antagonist was given together with an ADP receptor antagonist. Conclusions 1) Analysis of membrane fluidity provides a sensitive marker for platelet activation state. 2) Reduced membrane fluidity after combined platelet inhibitor treatments suggests reduced antiplatelet efficacy. Lasers Surg. Med. 39:414,426, 2001. © 2001 Wiley-Liss, Inc. [source] Intravascular low-power laser irradiation after coronary stenting: Long-term follow-upLASERS IN SURGERY AND MEDICINE, Issue 3 2001Ivan K. De Scheerder MD Abstract Background and Objective A high restenosis rate remains a limiting factor for percutaneous transluminal coronary angioplasty and stenting. The objective of this study was to evaluate the effect of intravascular red laser therapy (IRLT) on restenosis after stenting procedures in de novo lesions. Study Design/Materials and Methods A total of 68 consecutive patients were treated with IRLT in conjunction with coronary stenting procedures. Mean lesion length was 16.5,±,2.4,mm. Reference vessel diameter (RVD) and pre-minimal lumen diameter (MLD) were 2.90,±,0.15,mm and 1.12,±,0.26,mm, respectively. Results After treatment, MLD was 2.76,±,0.32 mm with no procedural complications or in-hospital adverse events. Angiographic follow-up (n,=,61) revealed restenosis in nine patients (14.7%) with rate by artery size of >,3 mm (n,=,21) 0%; 2.5,3.0 mm (n,=,28) 14.2%; and <,2.5 mm (n,=,12) 41.6%. Conclusion Intravascular red light therapy is safe, feasible, and reduces expected restenosis rate after coronary stenting. Lasers Surg. Med. 28:212,215, 2001. © 2001 Wiley-Liss, Inc. [source] Quality of Care for Acute Myocardial Infarction in Rural and Urban US HospitalsTHE JOURNAL OF RURAL HEALTH, Issue 2 2004Laura-Mae Baldwin MD ABSTRACT: Context: Acute myocardial infarction (AMI) is a common and important cause of admission to US rural hospitals, as transport of patients with AMI to urban settings can result in unacceptable delays in care. Purpose: To examine the quality of care for patients with AMI in rural hospitals with differing degrees of remoteness from urban centers. Methods: This cohort study used data from the Cooperative Cardiovascular Project (CCP), including 4,085 acute care hospitals (408 remote small rural, 893 small rural, 619 large rural, and 2,165 urban) with 135,759 direct admissions of Medicare beneficiaries ages 65 and older for a confirmed AMI between February 1994 and July 1995. Outcomes included use of aspirin, reperfusion, heparin, and intravenous nitroglycerin during hospitalization; use of beta-blockers, aspirin, and angiotensin-converting enzyme (ACE) inhibitors at discharge; avoidance of calcium channel blockers at discharge; and 30-day mortality. Findings: Substantial proportions of Medicare beneficiaries in both urban and rural hospitals did not receive the recommended treatments for AMI. Medicare patients in rural hospitals were less likely than urban hospitals' patients to receive aspirin, intravenous nitroglycerin, heparin, and either thrombolytics or percutaneous transluminal coronary angioplasty. Only ACE inhibitors at discharge was used more for patients in rural hospitals than urban hospitals. Medicare patients in rural hospitals had higher adjusted 30-day post-AMI death rates from all causes than those in urban hospitals (odds ratio for large rural 1.14 [1.10 to 1.18], small rural 1.24 [1.20 to 1.29], remote small rural 1.32 [1.23 to 1.41]). Conclusions: Efforts are needed to help hospital medical staffs in both rural and urban areas develop systems to ensure that patients receive recommended treatments for AMI. [source] The Predictive Value of Exercise QRS Duration Changes for Post-PTCA Coronary EventsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2003Shai Efrati Background: The sensitivity and predictive values of exercise ECG testing using ST-T criteria after percutaneous transluminal coronary angioplasty (PTCA) are low, precluding its routine use for screening for restenosis. The predictive value of QRS duration criteria during exercise testing (ET) ECG after PTCA for future coronary events has not been reported. The aim of the study was to compare QRS duration changes with ST-T criteria during ET, as a predictor of coronary events after PTCA. Methods: A prospective study of 206 consecutive patients who underwent ET at a mean of 34 ± 14 days after their first PTCA, and were the followed for a mean of 23 ± 9 months. Patients were divided by QRS duration into two groups,Q1: ischemic response (QRS duration prolongation of more than 3 ms relative to the resting duration), and Q2: normal response (QRS duration shortening or without change from resting duration). Patients were also divided by their ST-T response, S1: ischemic response, and S2: normal response. Results: During follow-up 52 patients (58%) experienced restenosis or MI, or underwent CABG,Q1: 44 (85%), Q2: 8(15%) (P < 0.0002), S1: 8 (15%), S2: 44 (85%), (P < 0.641), two patients died,Q1: 1 (1%) and Q2: 1 (1%). For QRS and ST-T, the relative risk of having at least one of the coronary events was 4.02 (CI 2.1,9.9) versus 1.13 (CI 0.8,2.9), respectively. The sensitivity for future coronary events was 85% and 52% and the specificity was 48% and 98% for the QRS and ST-T criteria, respectively. Conclusion: QRS prolongation during peak ET ECG after PTCA is a more sensitive marker than ST-T criteria for detection of patients at risk for later coronary events. [source] Current status of rotational atherectomyCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2004Erdal Cavusoglu MD Abstract Despite the increasing use of percutaneous transluminal coronary angioplasty and intracoronary stent placement for the treatment of obstructive coronary artery disease, a large subset of coronary lesions cannot be adequately treated with balloon angioplasty and/or intracoronary stenting alone. Such lesions are often heavily calcified or fibrotic and undilatable with the present balloon technology and attempts to treat them with balloon angioplasty or intracoronary stent placement often lead to vessel dissection or incomplete stent deployment with resultant adverse outcomes. Rotational atherectomy remains a useful niche device for the percutaneous treatment of such complex lesions, usually as an adjunct to subsequent balloon angioplasty and/or intracoronary stent placement. In contrast to balloon angioplasty or stent placement that widen the coronary lumen by displacing atherosclerotic plaque, rotational atherectomy removes plaque by ablating the atherosclerotic material, which is dispersed into the distal coronary circulation. Other lesion subtypes amenable to treatment with this modality include ostial and branch-ostial lesions, chronic total occlusions, and in-stent restenosis. This review discusses the technique and principles of rotational atherectomy, the various treatment strategies for its use (including adjunctive pharmacotherapy), the lesion-specific applications for this device, and the complications unique to this modality. Recommendations are also made for its use in the current interventional era. Catheter Cardiovasc Interv 2004;62:485,498. © 2004 Wiley-Liss, Inc. [source] Bivalirudin-associated intracoronary thrombosis during ,-brachytherapy and its experimental validation in acute swine modelCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2004Pramod K. Kuchulakanti MD Abstract Bivalirudin is indicated for use as an anticoagulant in patients with unstable angina undergoing percutaneous transluminal coronary angioplasty. Cases of intracoronary thrombosis have been reported with ,-radiation when bivalirudin is used as an anticoagulant. We report two cases of intracoronary thrombosis with ,-radiation when bivalirudin is used. Catheter Cardiovasc Interv 2004;62:209,213. © 2004 Wiley-Liss, Inc. [source] Trials and tribulations associated with angina and traditional therapeutic approachesCLINICAL CARDIOLOGY, Issue S1 2007Prakash C. Deedwania M.D. Abstract Ischemic heart disease is the foremost cause of death in the United States and the developed countries. Stable angina is the initial manifestation of ischemic heart disease in one half of the patients and becomes a recurrent symptom in survivors of myocardial infarction (MI) and other forms of acute coronary syndromes (ACS). There are multiple therapeutic modalities currently available for treatment of anginal symptoms in patients with stable CAD. These include anti-anginal drugs and myocardial revascularization procedures such as coronary artery bypass graft surgery (CABGS), percutaneous transluminal coronary angioplasty (PTCA) and percutaneous coronary intervention (PCI). Anti-anginal drug therapy is based on treatment with nitrates, beta blockers, and calcium channel blockers. A newly approved antianginal drug, ranolazine, is undergoing phase III evaluation. Not infrequently, combination therapy is often necessary for adequate symptom control in some patients with stable angina. Howerever, there has not been a systematic evaluation of individual or combination antianginal grug therapy on hard clinical end points in patients with stable angina. Most revascularization trials that have evaluated treatment with CABGS, PTCA, or PCI in patients with chronic CAD and stable angina have not shown significant improvement in survival or decreased incidence of non-fatal MI compared to medical treatment. In the CABGS trials, various post-hoc analyses have identified several smaller subgroups at high-risk in whom CABGS might improve clinical outcomes. However, there are conflicting findings in different reports and these findings are futher compromised due to the heterogeneous groups of patients in these trials. Moreover, no prospective randomized controlled trial (RCT) has confirmed an advantage of CABGS, compared to medical treatment, in reduction of hard clinical outcomes in any of the high-risk subgroups. Based on the available data, it appears reasonable to conclude that for most patients (except perhaps in those with presence of left main disease > 50% stenosis) there is no apparent survival benefit of CABGS compared to medical therapy in stable CAD patients with angina. Although these trial have reported better symptom control associated with the revascularization intervention in most patients, this has not been adequately compared using modern medical therapies. Available data from recent studies also suggest treatment with an angiotensin converting enzyme inhibitor (ACEI), a statin and a regular exercise regimen in patients with stable CAD and angina pectoris. Copyright © 2007 Wiley Periodicals, Inc. [source] Staged revascularization in critically ill patients with coronary artery diseaseCLINICAL CARDIOLOGY, Issue 5 2001Nasser Jowhar Hayat M.D., Ph.D. Abstract Background: Critically ill patients undergoing bypass surgery experience a higher mortality and morbidity. Hypothesis: The study was undertaken to evaluate the efficacy and value of percutaneous transluminal coronary angioplasty (PTCA) as a bridge to coronary artery bypass graft surgery (CABG) in high-risk patients with refractory unstable angina or cardiogenic shock. Methods: We present 11 seriously unstable patients with severe multivessel coronary artery disease undergoing culprit vessel PTCA. Angioplasty was performed not as a definitive procedure but rather as a bridge to surgical revascularization. All the patients had sustained at least one myocardial infarction prior to catheterization, all had refractory unstable angina, eight patients had only a single patent coronary artery, and five patients were in cardiogenic shock. Results: Following PTCA, all patients enjoyed a stable in-hospital period. One patient died 12 weeks after successful PTCA while awaiting second CABG. Seven patients subsequently underwent CABG and are doing well. The remaining three patients were also advised to undergo CABG, but elected to continue medical management. Conclusions: Coronary angioplasty of the culprit vessel may play a role as a bridge to surgery in critically ill patients. [source] | ||||||||||