Elective Coronary Angioplasty Research Articles

Outcomes of a System-Wide Protocol for Elective and Nonelective Coronary Angioplasty at Sites Without On-site Surgery: The Mayo Clinic Experience

To compare outcomes of percutaneous coronary interventions (PCIs) at 2 community hospitals without on-site surgery (Franciscan Skemp Healthcare and Immanuel St. Joseph's Hospital) with a center with on-site surgery (Saint Marys Hospital). Using a matched case-control design, we studied 1842 elective and 667 nonelective PCI procedures (myocardial infarction [MI]/cardiogenic shock) performed from January 1, 1999, through December 31, 2007. The quality assurance protocol included operator volume and training, application of a risk-adjustment model, transport protocol, and database participation. We compared in-hospital mortality and/or emergent coronary artery bypass surgery after PCI at Franciscan Skemp Healthcare and Immanuel St. Joseph's Hospital, which do not have on-site surgery, with Saint Marys Hospital, a medical center with the capability to perform coronary artery bypass grafting on site. Of 22 baseline variables, significant imbalances between matched groups were present in only 3 (hyperlipidemia, history of MI, American College of Cardiology/American Heart Association B2/C type lesion) in the elective group and 2 (Canadian Cardiovascular Society class III/IV angina, multivessel disease) in the nonelective group. The primary end point occurred in 0.3%, 0.1%, and 0.6% of patients undergoing elective PCI (P=.07) and 3.3%, 3.3%, and 3.7% of patients undergoing nonelective PCI (P=.65) at Immanuel St. Joseph's Hospital, Franciscan Skemp Healthcare, and Saint Marys Hospital, respectively. The in-hospital mortality rate at Immanuel St. Joseph's Hospital and Franciscan Skemp Healthcare was comparable to that at Saint Marys Hospital for both elective (0.3%, 0.1%, 0.4%; P=.24) and nonelective PCI (2.6%, 2.4%, 3.1%; P=.49). No patient undergoing elective PCI required transfer for emergency cardiac surgery. Of the 21 transfers, 20 (95%) were in the setting of MI and cardiogenic shock or left main/3-vessel disease; 18 patients (86%) survived to discharge. Optimal outcomes with PCI have been observed at community hospitals without on-site cardiac surgical programs with application of a prospective, standardized quality assurance protocol.

Prognostic heterogeneity among patients with chronic stable coronary disease: determinants of long-term mortality after treatment with percutaneous intervention

To evaluate the risk and predictors of death in a large population of patients with stable coronary disease treated with percutaneous intervention. The study population comprised 1,276 patients with chronic angina or silent ischaemia who underwent elective coronary angioplasty. Baseline and in-hospital mortality data were prospectively collected for all patients during the index hospitalisation. Post-discharge outcome was assessed at out-patient clinic, by review of the patients' records, or direct phone contact. Deaths were classified as cardiac and non-cardiac. Age, peripheral arterial disease, congestive heart failure with NYHA class >or= III, triple-vessel disease, and procedural success (i.e. angiographic success for all lesions in the absence of peri-procedural infarction) remained as multivariate independent predictors of death. For the entire population 4-year cumulative all-cause and cardiac mortality were respectively 5.4% and 4.1%. Four-year mortality for patients without any multivariate predictor was 2.4%, while for patients with two or more predictors the death rate was 16.3% after four years. Patients with stable coronary disease undergoing percutaneous treatment have an overall low mortality rate after four years. Nevertheless, stable patients comprise a heterogeneous population in terms of risk profile, ranging from patients at very low risk of late death to individuals with a poor long-term prognosis.

Increases in serum concentration of human heart-type fatty acid-binding protein following elective coronary intervention

Background: Heart-type fatty acid-binding protein (H-FABP) is considered a marker of myocardial necrosis but whether or not it is modified by myocardial ischemia is not clear. We sought to investigate if H-FABP serum levels increase following non-urgent coronary angioplasty.Methods: We studied 31 patients undergoing coronary angioplasty. Peripheral venous samples were drawn immediately before angioplasty, 1 h after the first balloon inflation and 24 h after the procedure and assayed for H-FABP.Results: Serum levels of H-FABP increased significantly at 1 h vs baseline from 2554 ± 1268 to 3322 ± 245 pg ml−1 (p = 0.024). However, no differences were observed between 1 h and 24 h after angioplasty (3268 ± 1861 vs 3322 ± 2459 pg ml−1, p = 0.87). Moreover, no significant difference was observed when we compared 24 h after angioplasty with the baseline (3268 ± 1861vs 2554 ± 1268 pg ml−1, p = 0.112).Conclusions: We conclude that H-FABP significantly increases after elective coronary angioplasty at 1 h compared with baseline values; whether or not this has any prognostic significance for future events, as it occurs with troponins, needs to be studied further.

Vectorcardiogram synthesized from the 12-lead electrocardiogram to image ischemia

Background Knowledge of the location and size of ischemic myocardium at risk for infarction could impact prehospital patient triage and reperfusion therapy. The 12-lead electrocardiogram (ECG) can roughly estimate ischemia size; however, individual precordial ECG leads are at different distances from the left ventricle (LV) and certain LV walls have greater effects on the ECG. Vectorcardiographic corrected orthogonal lead systems can display the magnitude and direction of the ST-segment “injury current” vector in 3-dimensional space. We assessed whether the vectorcardiographic ST-vector direction and magnitude derived from the ECG by the inverse-Dower method can estimate the location and size of ischemia. Methods and Results Thirty-two patients underwent elective coronary angioplasty with control and 5-minute balloon-occlusion ECG and sestamibi injection followed by single photon emission computed tomography (SPECT). The ST-vector direction derived from the inverse-Dower method was projected to an LV model with normal coronary artery anatomy. The graphical display of ST-vector location could discriminate among occlusions of the different coronaries. The ST-vector located ischemia within the SPECT defect in 75% (24/32) of all patients and 96% (24/25) of patients with ischemia in more than 12% of the LV. ST-vector magnitude had a Spearman correlation of r = 0.68 ( P < .0001) with SPECT ischemia size. Conclusions The 3-dimensional ST vector derived from the ECG can be graphically projected onto an LV model to localize ischemia, and ST-vector magnitude correlates with ischemia size. Further study is warranted to assess the ability of vectorcardiographic imaging to risk-stratify and provide decision-support for patients with acute myocardial infarction.

Development of an automated method for display of ischemic myocardium from simulated electrocardiograms

Background Knowledge of the size and location of ischemic myocardium during acute coronary occlusion could provide decision support before reperfusion therapy. Electrocardiogram (ECG) scores based on the number of leads and the sum of ST-segment elevation have been unreliable in quantifying ischemia. We aimed to develop a new method to graphically display ischemic myocardium from simulated ECGs (DIMS-ECG) associated with known ischemic regions. Methods Twenty-one patterns of ischemia based on normal coronary anatomy were programmed into the freely available program ECGSIM ( www.ecgsim.org). Minor variations of these patterns and 5 levels of ischemia severity produced 45 455 ECGs; 1000 normal ECGs were also added. Given a de novo ECG (an ECG from a patient), ST-segment and T-wave measurements are compared with ECG measurements in the database. The closest 200 matches are selected, and the corresponding ischemic areas are “averaged” to create a graphical display of the ischemic myocardium. Results Three patients are presented who underwent elective coronary angioplasty with continuous ECG recording and scintigraphically defined ischemic myocardium. Based on ECG analysis, the program graphically displays the ischemic myocardium with close agreement to the scintigraphic images. The program's source code and the ECG database will be made freely available. Conclusions The DIMS-ECG method graphically displays ischemic myocardium from information contained in the 12-lead ECG based on a novel approach to use a large simulated database instead of rule- or score-based method. After further development and testing, the DIMS-ECG method could be used to risk stratify patients with acute myocardial infarction.

Elevated CK-MB values after routine angioplasty predicts worse long-term prognosis in low-risk patients

The long-term prognostic value (>5 years) of elevated cardiac biomarkers after elective coronary angioplasty is yet not clear. Most previous studies have included high risk, unstable patients. The aim of this study was to determine the prognostic value of CK-MB mass > or = three times the reference after elective angioplasty in low-risk patients with stable angina. A total of 278 consecutive patients were included in the final analysis. Patients with elevated CK-MB values at baseline, and those suffering an acute coronary syndrome <1 month before the time of inclusion, were excluded. Blood samples were drawn just before and 1-3 hours, 4-8 hours after the procedure and the next morning. Nineteen patients (6.8%) had peak CK-MB mass values > or =15 microg/L (three times the reference), and 259 patients had values <15 microg/L (defined as controls). No patient developed new Q-waves on ECG. The median follow-up time was 80.5 months. None of the patients died during the procedure or within the first 30 days after angioplasty, confirming a low risk cohort. All cause mortality, readmission for acute coronary syndromes and target lesion revascularisation (TLR) were more frequent in patients with high CK-MB, 42.1% vs. 22.8%, p=0.034 (log rank). In a multivariate logistic regression analysis, high CK-MB and former angioplasty were the only variables independently related to a reduced event-free survival. CK-MB mass values > or = three times the reference after elective angioplasty predicts reduced long-term event-free survival.

Myocardial damage in successful single vessel coronary angioplasty as assessed by creatinine kinase and its myocardium band isoenzyme levels.

To determine the frequency of myocardial damage in elective, successful, single vessel percutaneous coronary angioplasty by assessing myocardial band (MB), creatinine kinase levels and to find out the association of common modifiable risk factors with myocardial damage in patients undergoing single vessel coronary angioplasty. Descriptive. Armed Forces Institute of Cardiology / National Institute of Heart Disease, Rawalpindi, from September 2006 to September 2007. Fifty patients undergoing elective and successful single vessel percutaneous coronary angioplasty were evaluated with creatinine kinase and creatinine kinase MB levels before and after 8 hours and 1st day following coronary angioplasty. Studied variables included the length of stent deployed, maximum deployment pressure and total balloon inflation time, apart from hypertension, cholesterol level, smoking and diabetes mellitus. Out of 50 patients, 9 had raised creatinine kinase at 8 hours (18%) and 10 had raised creatinine kinase (20%) on 1st day following coronary angioplasty, 7 (14%) patients and 8 (16%) patients had raised creatinine kinase MB levels at 8 hours and 1st day following coronary angioplasty respectively. The rise of either was equal to or more than 3 times the normal limits. Modifiable risk factors, significantly associated with myocardial damage, were diabetes mellitus (p=0.006) and LDL levels (p=0.009) in patients undergoing single vessel coronary angioplasty. Successful elective, uncomplicated, single vessel coronary angioplasty resulted in some myocardial damage evident by mild rise in cardiac enzymes but rise of creatinine kinase MB above 3 times of normal, which signifies percutaneous coronary angioplasty-related myocardial infarction, was not seen. There was a significant association between diabetes mellitus, LDL levels and myocardial damage in patients undergoing coronary angioplasty but no significant association was found between hypertension, smoking and myocardial damage.

Radiation Exposure During Elective Coronary Angioplasty: The Effect of Flat-Panel Detection

Coronary angiography and angioplasty have to date been performed using digital angiography and fluoroscopic systems which incorporate an image intensifier (II). More recently flat-panel (FP) detectors have been introduced which are thought to improve spatial resolution. However, there is limited data on the effect of flat-panel detection on radiation exposure. We sought to determine the impact of flat-panel on cumulative radiation exposure in patients undergoing elective coronary angioplasty at our institution. Patients who underwent elective coronary angioplasty in the six months prior to and following upgrade of our Toshiba catheterisation laboratory from image intensifier to flat-panel were included. Demographic and radiation data were collected prospectively and the same five operators performed interventions during the 12-month period. Radiation data was obtained from the dose-area product meter intrinsic to the fluoroscopy system. One hundred and thirty seven patients underwent elective angioplasty over the 12-month period (68 II, 69 FP). Cumulative radiation exposure was increased in flat-panel cases (99, 129 Gy cm(2) versus 71, 77 Gy cm(2), p=0.001). This increase was independent of patient weight (78+/-15 kg versus 78+/-17 kg, p=NS), screening time (19+/-12 min versus 18+/-13 min, p=NS) and total number of digital acquisitions (1475, 820 versus 1668, 1365, p=NS). The total amount of contrast dye did not differ between flat-panel and image intensifier cases (195+/-76 ml versus 194+/-79 ml, p=NS). Adoption of flat-panel detector technology increases radiation exposure. This may have important safety implications for catheterisation laboratory staff and patients undergoing multiple interventional procedures.

Ethanol Abolishes Ischemic Preconditioning in Humans

This study sought to assess the effect of acute alcohol intake on ischemic preconditioning (IPC) in humans using the clinical model of 2 sequential balloon inflations during a percutaneous coronary intervention (PCI). Ischemic preconditioning is the most potent form of endogenous myocardial protection from irreversible ischemic injury. Experimental observations suggest that acute ethanol administration might abolish IPC. We studied 30 consecutive patients (22 men, mean age 65 years) undergoing elective coronary angioplasty who were randomized to receive an oral dose of 40 g ethylic alcohol (administered as 149 ml of Gordon's Gin) or 149 ml of water 30 min before PCI. Intracoronary electrocardiogram was continuously monitored to assess the greatest ST-segment elevation or depression from baseline. In placebo-treated patients, the change of ST-segment shift during the second inflation was significantly smaller than that during the first inflation (19.3 +/- 9.1 vs. 15.7 +/- 8.7, p = 0.005). In contrast, in gin-treated patients, the change of ST-segment shift during the second inflation was significantly greater than that during the first inflation (18.7 +/- 7.2 vs. 22 +/- 10, p = 0.03). The group-inflation interaction for ST-segment changes was highly significant (p < 0.001). This randomized, prospective study in humans shows that administration of a moderate dose of ethanol abolishes IPC occurring during sequential episodes of myocardial ischemia and is associated with worsening ischemia. Based on our study, intake of moderate to high doses of alcoholic beverages should be avoided in patients at high risk of acute myocardial infarction.

Interpretation of the Appropriate Guideline for Elective Coronary Angioplasty for Cases with Stable Angina Pectoris

Interpretation of the Appropriate Guideline for Elective Coronary Angioplasty for Cases with Stable Angina Pectoris

Maximal increase in sensitivity with minimal loss of specificity for diagnosis of acute coronary occlusion achieved by sequentially adding leads from the 24-lead electrocardiogram to the orderly sequenced 12-lead electrocardiogram

Objectives This study investigates whether sequential addition of inverted (negative) leads from the 24-lead electrocardiogram (ECG) to the orderly sequenced 12-lead ECG would identify a number of leads with which the sensitivity for diagnosis of acute transmural ischemia is significantly increased with minimal loss of specificity. Background Acute transmural ischemia due to thrombotic coronary occlusion typically progresses to infarction. Its recognition is based on currently accepted ST-elevation myocardial infarction (STEMI) criteria with suboptimal sensitivity, which could be potentially increased by consideration of the principle that each of the 12 ECG leads can be inverted to provide an additional lead with the opposite (180°) orientation, generating a 24-lead ECG. Methods The study population included 162 patients who underwent prolonged coronary occlusion during elective percutaneous transluminal coronary angioplasty. Balloon occlusion was performed in the left anterior descending coronary artery (51 patients), in the right coronary artery (67 patients), or in the left circumflex coronary artery (44 patients). To be classified as indicative of the epicardial injury current of acute ischemia, the ECGs had to fulfill either the criteria of a consensus document from the American College of Cardiology or the European Society of Cardiology or thresholds for the inverted leads based on a population study from Scotland. Results The addition of −V1, −V2, −V3, −aVL, −I, aVR, and −III increased sensitivity from 61% to 78% ( P ≤ .01) and decreased specificity from 96% to 93% ( P = .06). Conclusions Addition of 7 leads from the 24-lead ECG, thus creating a 19-lead ECG, was found optimal for attaining high sensitivity while retaining high specificity when compared with the performance of the standard 12-lead ECG.

Sympathetic neural responses to coronary occlusion during balloon angioplasty

The sympathetic nervous system is a key modulator of prognosis and outcome in cardiac ischaemia and infarction. The effects of acute cardiac ischaemia on sympathetic neural traffic in humans are unknown. We tested the hypothesis that angioplasty, and associated transient myocardial ischaemia, elicits changes in neural circulatory control, including direct intraneural measures of sympathetic traffic. We measured muscle sympathetic nerve activity (MSNA), blood pressure and heart rate in 12 patients (11 men, one woman) undergoing clinically indicated elective coronary angioplasty of the left anterior descending (n = 7) or circumflex (n = 5) coronary artery. Baseline data were obtained for 2 min before occlusion. Each balloon inflation was designed to last up to 120 s. Coronary occlusion had no significant effect on blood pressure or heart rate. In contrast, occlusion resulted in a significant increase in MSNA, in 10 of the 12 patients, and in all seven of those patients undergoing angioplasty of the left anterior descending artery. The group mean increase in MSNA during occlusion was 36 +/- 11% (P = 0.008 versus preocclusion). MSNA increased within 60 s of occlusion (129 +/- 12% of baseline; n = 12; P = 0.04), and increased further during the next 60 s to 141 +/- 12% of baseline levels (n = 10; P < 0.001). Increases in MSNA were similar in patients with and without significant chest pain (39 +/- 9% versus 34 +/- 13%, respectively; P = 0.84). Acute coronary occlusion during angioplasty increases central sympathetic outflow, but there is no systematic change in heart rate. The increase in sympathetic nerve traffic cannot be explained by blood pressure changes or occlusion-related chest pain.

Risk of target lesion revascularization after coronary stenting in patients with and without chronic kidney disease

Rates of restenosis following percutaneous coronary intervention with stent placement are high in patients with advanced renal failure. Whether mild to moderate chronic kidney disease (CKD) is associated with a similarly increased need for short or long-term target lesion revascularization (TLR) following coronary stenting is uncertain. We analysed results from 1228 patients enrolled in four separate, randomized, controlled clinical trials who underwent elective coronary angioplasty with stenting and were prospectively followed for 5 years after the index procedure. Cox proportional hazards regression was used to correct for confounding and to estimate the short and long-terms risks of target lesion revascularization in patients with vs without mild to moderate CKD. During a median follow-up of 5 years, 205 patients (16.7%) required TLR with 59 (4.8%) requiring TLR after the first year. Mild (HR 1.07, 95% CI 0.74-1.53) and moderate (HR 0.95, 95% CI 0.552-1.64) CKD were not associated with an increase in the adjusted, overall-risk of TLR. However, mild to moderate CKD was associated with a non-significantly increased risk of late TLR (HR 1.40, 95% CI 0.73-2.69). Coronary stenting appears to be similarly effective in patients with mild to moderate CKD and patients with normal renal function. While target lesion revascularization is rarely needed beyond the first year after revascularization, long-term results of coronary stenting may be less-favourable in patients with CKD.

The Case for Outpatient Coronary Intervention

Over the past 30 years, dramatic improvements have been achieved in the safety of percutaneous coronary intervention (PCI) procedures, despite the increasing complexity of clinical and anatomic conditions treated. The need for emergent bypass surgery has declined from 8% in 1990 to far less than 1% in the current era, and the rate of vascular complications has declined dramatically as techniques have improved and procedural experience has increased. Given the remarkable current periprocedural safety profile of elective coronary intervention, has the time come for us to consider whether outpatient PCI can be safely performed? In this issue of Circulation , investigators from the Academic Medical Center of the University of Amsterdam investigated this question as part of the Elective PCI in Outpatient Study (EPOS).1 Article p 2299 The study by Heyde and colleagues randomly assigned 800 consecutive, elective, outpatient, planned PCI patients to a strategy of either same-day discharge or routine care that included an overnight observation in the hospital. The patients and providers were blinded to the assignment until after evaluation according to predefined criteria for those patients who required additional observation or treatment. All patients eligible for same-day discharge, regardless of assignment, were then strictly observed for 4 hours and then underwent a rigorous triage evaluation to determine if same-day discharge would be appropriate. At that time, those patients who were randomized to the same-day discharge group were discharged, whereas the patients randomized to the overnight hospitalization group were kept in-hospital for observation. The investigators found that 20% of patients in both disposition arms developed one of the predefined exclusions for same-day discharge. Of the ≈80% of patients suitable for same-day discharge, none suffered a cardiac event within 24 hours after PCI, and only 3 patients suffered a vascular complication, with no differences observed in the 2 …

Cytotoxic T Lymphocyte Antigen 4 Gene Polymorphism Associated With ST-Segment Elevation Acute Myocardial Infarction

Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a particularly important molecule in down-regulating T-cell expansion and cytokine production. The purpose of the present study was to determine the frequency distribution of an A/G single nucleotide polymorphism at position 49 in exon 1 of the CTLA-4 gene, which may be a functional related-genetic risk marker for the development of ST-segment elevation (ST-se) acute myocardial infarction (AMI). A total of 503 consecutive patients, consisting of 250 ST-se AMI patients undergoing primary coronary angioplasty (group 1), 203 angina pectoris patients undergoing elective coronary angioplasty (group 2) and 50 patients with chest pain and normal coronary angiographic findings (group 3), were enrolled in the present study. The frequency of the G/G genotype was significantly higher in group 1 (53.2%) than in groups 2 (33.0%) and 3 (36.0%) (p=0.0005). In group 1, patients with a G/G genotype had significantly higher levels of high-sensitivity C-reactive protein and white blood cell counts, and much higher incidences of multi-vessel disease, greater lesion lengths, advanced congestive heart failure (>or=class 3) and 30-day mortality, than patients with G/A or A/A genotypes (p values<0.05 in all cases). Multivariate analysis of the enrolled baseline variables (age, gender, diabetes mellitus, smoking, hypertension and hypercholesterolemia) and the genotypes (G/G, A/G and A/A) demonstrated that G/G genotype is the only independent predictor of development of AMI (p<0.0001). The G/G genotype polymorphism of the CTLA-4 gene is associated with increased risk of AMI.

Impact of Radial Artery Cannulation for Coronary Angiography and Angioplasty on Radial Artery Function

The radial artery is commonly used as a conduit in coronary artery bypass grafting. No data exist on the effects of radial sheath insertion on radial artery function. Because many patients considered for coronary artery bypass grafting have had previous radial procedures, it is important to understand any effects radial sheath insertion may have on radial artery function. Twenty-two patients who underwent elective coronary angiography or angioplasty with a 6Fr sheath through the right radial artery were studied. Radial artery function was assessed using ultrasound to measure flow-mediated dilation (FMD). Reactive hyperemia was produced by 5-minute cuff inflation on the arm to suprasystolic pressures. Radial artery diameter was measured at rest and 1 minute after cuff deflation. FMD was expressed as percent change in radial diameter compared with at rest. In all cases, the left radial artery was studied as a control. Patients were studied before sheath insertion, immediately after sheath insertion, and 6 weeks after sheath insertion. The FMD of the cannulated arm was 13.2% before sheath insertion versus 3.6% immediately after sheath insertion (p <0.01) and 0.2% (p <0.01) 9 weeks after sheath insertion. In contrast, there were no significant changes in the noncannulated arm at either time point. In conclusion, radial artery sheath insertion for coronary angiography or angioplasty results in immediate and persistent blunting of FMD, suggesting severe vasomotor dysfunction. Radial artery sheath insertion has important effects on radial artery function that must be considered when selecting radial conduits for coronary artery bypass grafting.

Improvement of the detection of myocardial ischemia thanks to information technologies

Background The standard 12-lead ECG remains one of the basic investigations for the early detection and assessment of acute coronary syndromes. It is easy to perform, anywhere and anytime, and can be digitally transmitted within minutes to an emergency medical service for remote advice and triage. But the conventional ST-segment deviation criteria are of limited diagnostic accuracy. The purpose of this study is to investigate how much the use of computerized ECG techniques based on the measurement of the serial spatiotemporal ECG changes could improve the detection accuracy of transmural myocardial ischemia. Methods We considered the serial changes of continuous 12-lead ECGs of 90 patients undergoing elective percutaneous coronary angioplasty (PTCA) recorded during balloon inflation as an experimental model of ECG changes induced by coronary artery occlusion. The spatiotemporal ECG changes were measured according to the CAVIAR method and assessed by multivariate discriminant analysis in reference to serial changes of control recordings and standard ECG criteria. Results The diagnostic accuracy of the CAVIAR criteria for ischemia detection was 97%, with sensitivity of 98% and specificity of 96%, whereas the diagnostic accuracy of the conventional ST-segment criteria was 74%, with sensitivity of 60% and specificity of 88%. The increase of overall performance was obtained for all the occlusion locations. Conclusions Computer-assisted quantitative serial ECG analysis, taking into account the spatiotemporal changes of the QRS and T waves, would provide the physician with additional information for significantly improving the detection of transmural myocardial ischemia.

Lifestyle change after elective percutaneous transluminal coronary angioplasty: an Australian perspective

Lifestyle change after elective percutaneous transluminal coronary angioplasty: an Australian perspective

Predictors and Prognostic Significance of Troponin-I Release following Elective Coronary Angioplasty

The objective of this study was to investigate the predictors and prognostic significance of post-procedural cardiac troponin (cTn)-I elevations in a consecutive series of patients who underwent elective percutaneous coronary intervention (PCI). cTn-I was measured in 100 patients immediately before and within 24 h after the elective PCI. Post-procedural cTn-I elevation was observed in 27 of the 100 patients. In multivariate analysis, basal haemoglobin values and the number of repeated balloon dilatations were found to be independent predictors of cTn-I elevation. During the follow-up period of 12 +/- 1.2 months, the cTn-I-positive group had more major adverse cardiovascular events than the cTn-I-negative group (33.3% versus 16.4%, respectively), but the difference was not significant. An increase in cTn-I levels following elective PCI procedures was frequent but did not predict a poor long-term outcome.

Are Drug-Eluting Stents Cost-Effective?

Since their commercial introduction in 2003, drug-eluting stents (DES) have rapidly altered the management of coronary artery disease. Before their development, the percutaneous management of coronary artery disease was performed predominantly by implantation of bare metal stents (BMS) made of either surgical stainless steel or metal alloys. Although such stents represented a considerable advance over balloon angioplasty alone, they remained limited by restenosis resulting from neointimal proliferation. As a result, ≈15% to 20% of patients treated with BMS required ≥1 repeat revascularization procedure within the 6 to 12 months after stent implantation.1 Despite numerous attempts at systemic pharmacotherapy, device modification, and even use of ionizing radiation, the rate of restenosis after BMS implantation remained largely unaffected. Response by Eisenberg p 1744 Over the past 5 years, effective DES have become the first device to substantially reduce the incidence of restenosis after stent implantation. By delivering high concentrations of either antiproliferative or immunomodulatory compounds directly to the site of arterial injury and by controlling this delivery through polymer-based drug release, both sirolimus- and paclitaxel-eluting stents have safely and effectively inhibited the proliferative process that results in in-stent restenosis. In pivotal clinical trials, both sirolimus- and paclitaxel-eluting stents have reduced rates of angiographic restenosis by 70% to 90% compared with conventional BMS designs, with parallel reductions in the need for clinically driven target vessel revascularization (TVR).2–4 As a result, in April 2003, DES were approved for use in clinical practice in the United States. Within 9 months of their introduction, DES made up 35% of all stent implantations in the United States,5 and their use has increased rapidly since that time. At our own institution, DES comprised >85% of all stents implanted during the past year, and national estimates are that >90% of all percutaneous coronary intervention (PCI) procedures …