Transradial approach in the catheterization laboratory: pros/cons and suggestions for successful implementation.

In the last decade the radial access use in the catheterization laboratory has sensibly grown up worldwide. From an initial sporadic use as alternative but challenging vascular approach, radial artery is today utilized by default for percutaneous procedures in many centers. The tangible interest in the transradial approach is also testified by increasing presence of specific sessions in the main interventional meetings and by continuous development of dedicated catheters and ancillary devices by manufacturers. In this review we describe the anatomical characteristics and the technical aspects related to transradial procedure underlying its pros/cons in opposition to femoral access. We also point up practical instructions trying to resolve the main concerns related to an extensive use of radial approach in catheterization laboratory, such as increased operator's discomfort, higher radiation exposure, safety and feasibility for complex high-risk procedures.

Current concepts on antiplatelet therapy: focus on the novel thienopyridine and non-thienopyridine agents.

Thienopyridines are a class of drug targeting the platelet adenosine diphosphate (ADP) 2 receptor. They significantly reduce platelet activity and are therefore clinically beneficial in settings where platelet activation is a key pathophysiological feature, particularly myocardial infarction. Ticlopidine, the first of the class introduced to clinical practice, was soon challenged and almost completely replaced by clopidogrel for its better tolerability. More recently, prasugrel and ticagrelor have been shown to provide a more powerful antiplatelet action compared to clopidogrel but at a cost of higher risk of bleeding complications. Cangrelor, a molecule very similar to ticagrelor, is currently being evaluated against clopidogrel. Considering the key balance of ischemic protection and bleeding risk, this paper discusses the background to the development of prasugrel, ticagrelor, and cangrelor and aims to characterise their risk-benefit profile and possible implementation in daily practice.

What is the risk of intensifying platelet inhibition beyond clopidogrel? A systematic review and a critical appraisal of the role of prasugrel.

Thienopyridines are a class of drug targeting the platelet adenosine diphosphate 2 receptor. They have been shown to significantly reduce platelet activity exerting an important role in those clinical settings in which such an effect is beneficial. Ticlopidine was first to be introduced several years ago but it was quickly replaced by clopidogrel as it had a better risk/benefit profile. Recently, prasugrel has been developed and tested in several ex vivo studies and clinical trials showing able to provide a more powerful antiplatelet effect at the expense of a higher risk of bleeding complications. Great debate rose around its recent approval in the US as well as in Europe. This review aims at exploring the development and available clinical data of this third-generation thienopyridine while discussing its practical implementation in routine practice.

Myocardial infarction after percutaneous coronary intervention: a meta-analysis of troponin elevation applying the new universal definition.

AIM: Elevation of Troponin after scheduled percutaneous coronary intervention (PCI) is a recognized consequence. We sought to evaluate the prognostic significance and impact of the newly published definition of PCI-related myocardial infarction (MI) according to which any troponin elevation >3 times the upper reference limit identify a peri-procedural MI. METHODS: Search of BioMedCentral, CENTRAL, mRCT and PubMed (updated May 2008). Outcomes of interest were: MACE [the composite of all cause death, MI, repeat target vessel PCI (re-PCI) and coronary artery bypass grafting (CABG)]; single end points were also assessed. RESULTS: Fifteen studies have been included totalling 7578 patients. Troponin elevation occurred in 28.7% of the procedures. The incidence of PCI-related MI according to the new definition was 14.5%. During the hospitalization, any level of raised troponin was associated with an increased risk of MACE [OR 11.29 (3.00-42.48), Number needed to harm (NNH) 5], death [OR 7.16 (1.95-26.27), NNH = 100], MI [OR 30.85 (6.05-157.38), NNH = 4] and re-PCI [OR 4.13 (1.23-13.88), NNH = 50]. Patients with PCI-related MI had an increased risk of death [OR 17.25 (2.71-109.96), NNH = 100] and re-PCI [OR 10.86 (3.2-36.94), NNH = 25]. At follow up of 18 months any troponin elevation was associated with an increased risk of MACE [OR 1.48 (1.12-1.96), NNH = 20], death [OR 2.19 (1.59-3.00), NNH = 50], MI [OR 3.29 (2.71-6.31), NNH = 33] and re-PCI [OR 1.47 (1.06-2.03), NNH = 25]. In patients with PCI-related MI the risk of MACE was further increased: OR 2.25 (1.26-4.00), NNH = 3. An increase of the troponin level below the cut-off was not associated with MACE. CONCLUSION: A diagnosis of MI according to the new guidelines applies to 15% of patients undergoing PCI and these patients are at high risk of further adverse events both during the hospital stay and at 18 months.

EuroSCORE as predictor of in-hospital mortality after percutaneous coronary intervention.

OBJECTIVE: To date, no common risk stratification system is available to predict the risk of surgical or percutaneous myocardial revascularisation in patients with coronary artery disease (CAD). Thus, we sought to assess the European System for Cardiac Operative Risk Evaluation (EuroSCORE) validity to predict in-hospital mortality after percutaneous coronary intervention (PCI). DESIGN, SETTING AND PARTICIPANTS: EuroSCORE was prospectively and systematically assessed in 1173 consecutive patients undergoing PCI in a high-volume single centre between April 2005 and October 2006. MAIN OUTCOME MEASURE: The receiver-operating characteristics (ROC) curve was used to describe performance and accuracy of the EuroSCORE risk model for the prediction of in-hospital mortality after PCI. RESULTS: The EuroSCORE model demonstrated an overall relation between EuroSCORE rank and the incidence of in-hospital mortality, showing consistency in predicting patient risk across many subgroups and levels of global risk. At multivariable logistic regression analysis the EuroSCORE value was an independent in-hospital mortality predictor (p = 0.002) together with left main disease (p = 0.005), procedural urgency (p = 0.001), ACC/AHA C type lesion (p = 0.02) and PCI failure (p = 0.01). The area under the ROC curve for the EuroSCORE system was 0.91 (95% CI 0.86 to 0.97), indicating a good ability of the model to discriminate patients at risk of dying during the index hospitalisation. CONCLUSION: The EuroSCORE risk model, already extensively validated for the prediction of early mortality following open-heart surgery, can also be efficiently utilised in the setting of PCI. The introduction of the EuroSCORE assessment in patients with documented CAD may help to improve the revascularisation strategy decision-making process.

Major improvement of percutaneous cardiovascular procedure outcomes with radial artery catheterisation: results from the PREVAIL study.

OBJECTIVE: To obtain a "snapshot" view of access-specific percutaneous cardiovascular procedures outcomes in the real world. DESIGN: Multicentre, prospective study performed over a 30-day period. SETTING: Nine hospitals with invasive cardiology facilities, reflecting the contemporary state of healthcare. PATIENTS: Unselected consecutive sample of patients undergoing any percutaneous cardiovascular procedure requiring an arterial access. INTERVENTIONS: Percutaneous cardiovascular procedures by radial or femoral access MAIN OUTCOME MEASURES: The primary outcome was the combined incidence of in-hospital (a) major and minor haemorrhages; (b) peri-procedural stroke; and (c) entry-site vascular complications. The secondary outcome was the combined incidence of in-hospital death and myocardial infarction/reinfarction. For analysis purposes, outcomes were allocated to arterial access-determined study arms on an intention-to treat basis. Multivariable analysis adjusted using propensity score was performed to correct for selection bias related to arterial site. RESULTS: A total of 1052 patients were enrolled: 509 underwent radial access and 543 femoral access. In both groups, 40% underwent a coronary angioplasty. Relative to femoral access, radial access was associated with a lower incidence both of primary (4.2% vs 1.96%, p = 0.03, respectively) and secondary endpoints (3.1% vs 0.6%, p = 0.005, respectively). Multivariate analysis, adjusted for procedural and clinical confounders, confirmed that intention-to-access via the radial route was significantly and independently associated with a decreased risk both of primary (OR 0.37, 95% CI 0.16 to 0.84) and secondary endpoints (OR 0.14, 95% CI 0.03 to 0.62). CONCLUSIONS: Our study indicates strikingly better outcomes of percutaneous cardiovascular procedures with radial access versus femoral access in contemporary, real-world clinical settings.

Pexelizumab in ischemic heart disease: a systematic review and meta-analysis on 15,196 patients.

OBJECT: Pexelizumab is a humanized monoclonal antibody inhibiting C5 complement. It has been postulated to improve outcomes in patients undergoing coronary artery bypass surgery and urgent reperfusion therapy for ST elevation myocardial infarction. We aimed at evaluating the risk/benefit profile of pexelizumab (bolus + infusion) versus placebo on top of current approaches in the management of patients with ST elevation myocardial infarction or undergoing coronary artery bypass. METHODS: We conducted a search of BioMedCentral, CENTRAL, mRCT, and PubMed without language restrictions (updated October 2007) for randomized controlled trials. Outcomes of interest were the risk of major adverse events (the composite of all-cause death, myocardial infarction, and thromboembolic stroke), the risk of single end points, and heart failure. RESULTS: Seven trials were included (15,196 patients: 7019 patients with ST elevation myocardial infarction and 8177 undergoing coronary bypass surgery). No benefit of adding pexelizumab was found in the overall analysis for major adverse events (OR 0.91 [0.76-1.09]; P = .29], death (OR 0.79 [0.61-1.03], P = .11], myocardial infarction (OR 1.04 [0.89-1.22]; P = .14), stroke (OR 0.95 [0.66-1.38]; P = .8), heart failure (OR1.0 [0.82-1.22]; P = .99), nor in the settings of patients with ST elevation myocardial infarction treated with mechanical or pharmacologic reperfusion therapy. Pexelizumab was associated with a 26% reduction of the risk of death in the setting of coronary artery bypass (OR 0.74 [0.58-0.94]; P = .01). The number needed to treat was 100. CONCLUSION: Our data ruled out the hypothesis of any benefit of adding pexelizumab on top of currently available therapies for ST elevation myocardial infarction. However, pexelizumab reduces the risk of death in patients undergoing coronary artery bypass grafting.

Repeat thrombolysis or conservative therapy vs. rescue percutaneous coronary intervention for failed thrombolysis: systematic review and meta-analysis.

BACKGROUND: Despite proven advantages of primary percutaneous coronary intervention (PCI), thrombolysis remains the first line treatment for ST-elevation myocardial infarction (STEMI) worldwide. Management of patients with failed thrombolysis is still debated, and data from existing randomized controlled trials are conflicting. AIM: To compare the risk/benefit profile of repeat thrombolysis (RT) vs. rescue PCI in patients with failed thrombolysis. METHODS: Search of BioMedCentral, CENTRAL, mRCT and PubMed for randomized controlled trials comparing rescue PCI vs. conservative therapy and/or RT vs. conservative therapy. Outcomes of interest assessed by adjusted indirect meta-analysis: major adverse events (MAE, defined as the composite of overall mortality and re-infarction), stroke, congestive heart failure (CHF), major bleeds (MB), and minor bleeds. Overall mortality and re-infarction have been also analysed individually. RESULTS: Eight trials were included (1318 patients). Follow-up ranged from 'in-hospital' to 6 months. No significant difference was found for the risk of MAE [OR 0.93(0.26-3.35), P = 0.4], overall mortality [OR 1.01(0.52-1.95), P = 0.15], stroke [OR 5.03(0.64-39.1), P = 0.58] and CHF [OR 0.74(0.28-1.96), P = 0.6]. Compared with conservative therapy, rescue PCI was associated with a 70% reduction in the risk of re-infarction [OR 0.32(0.14-0.74), P = 0.008], number needed to treat 17. No difference in terms of MB was found [OR 0.5(0.1-2.5), P = 0.09], while a greater risk of minor bleeds was observed with rescue PCI [OR 2.48(1.08-5.7), P = 0.04], number needed to harm 50. CONCLUSION: Although the observed benefit is modest, these data support the use of PCI after failed thrombolysis.

Sudden coronary death, fatal acute myocardial infarction and widespread coronary and myocardial inflammation.

BACKGROUND: T-lymphocyte activation within atherosclerotic plaque, and widespread to the myocardium, has been shown in patients with acute coronary syndromes. OBJECTIVE: To investigate the presence of T-lymphocyte infiltrate at different stages of acute coronary syndromes by studying patients with sudden coronary death, acute myocardial infarction (AMI) and healed infarction, in comparison with patients with myocarditis and patients with non-ischaemic heart failure. METHODS: 72 cases were studied at autopsy: 12 dying of sudden coronary death (group 1), 12 dying <4 weeks (group 2) and 12 dying >4 months after AMI (group 3), 12 with active lymphocytic myocarditis (group 4), 12 with hypertensive heart disease (group 5), and 12 control subjects (group 6). Light microscopy was performed to measure the number of activated T-lymphocytes (CD3+/DR+) in the myocardium and coronary artery wall, and intercellular adhesion molecule-1 (ICAM-1) expression in the myocardium. RESULTS: Activated T-lymphocyte infiltrates and ICAM-1 myocardial expression in both remote and peri-infarction regions and activated T-lymphocytes within the epicardial coronary artery wall of both the infarct- and non-infarct-related arteries were found in groups 1, 2 and 3, whereas myocardial, but not coronary, infiltrates were found in groups 4 (p<0.001 vs groups 1, 2 and 3 for coronary infiltrates). Groups 5 and 6 had no evidence of myocardial or coronary inflammation (p<0.001 vs groups 1, 2 and 3). CONCLUSIONS: The study shows the presence of a lymphocytic infiltrate in both coronary arteries and myocardium and a proinflammatory phenotype shift in the myocardium associated with acute coronary thrombosis in patients dying suddenly, shortly, or even late after coronary thrombosis.

Ximelagatran/melagatran against conventional anticoagulation: a meta-analysis based on 22,639 patients.

BACKGROUND: The oral direct thrombin inhibitor ximelagatran, and its active form, melagatran, have been tested in various clinical conditions as a promising alternative to conventional anticoagulant therapy (CAT), despite some concerns over potentially serious liver injury. OBJECTIVES: To assess its risk/benefit profile, a systematic review and meta-analysis of all randomised controlled trials (RCTs) comparing xi-/melagatran to CAT was performed. METHODS: Leading medical databases were searched. The rates of major adverse events (MAE: all cause death, nonfatal myocardial infarction, nonfatal thromboembolic stroke, nonfatal pulmonary embolism), major bleeds (MB), and hepatotoxicity were compared. Out of 140 potentially relevant citations, 13 RCTs enrolling 22,639 patients were included. Indications for treatment were: 1) perioperative prophylaxis of deep vein thrombosis (DVT); 2) management of DVT; and 3) stroke prevention in atrial fibrillation. RESULTS: Overall, the risk of MAE (OR 0.98 [0.83-1.17]) and MB (OR 1.01 [0.69-1.47]) did not differ significantly between xi-/melagatran and CAT. There was a clear trend towards an increased risk of hepatotoxicity (OR 1.74 [0.50-6.01]), with an incidence of 5.8% with xi-/melagatran versus 2.3% with CAT (p<0.001); more specifically, the rate of hepatotoxicity was markedly augmented in the management of DVT (OR 5.16 [3.38-7.89]), for treatment durations > or = 3 months (OR 6.73 [5.01-9.05]), and in the prevention of atrial fibrillation-related stroke (OR 8.31 [5.65-12.23]). Two fatal cases of liver injury occurred with xi-/melagatran. CONCLUSIONS: Although comparable to CAT in terms of MAE and MB, xi-/melagatran carries a prohibitive risk of hepatotoxicity that cannot be ignored. Newer long-term alternatives are urgently needed.

Retrograde posterior tibial artery access for below-the-knee percutaneous revascularization by means of sheathless approach and double wire technique.

Arterial revascularization by means of percutaneous transluminal angioplasty (PTA) is a mainstay in the management of patients with peripheral artery disease and critical limb ischemia (CLI). While cross-over access from the contralateral femoral artery or antegrade access from the ipsilateral femoral artery are most commonly used when approaching subjects with CLI, PTA may occasionally fail when performed from these routes. We hereby report a patient in whom we performed retrograde arterial access through the posterior tibial artery, thus enabling recanalization of a challenging below-the-knee chronic total occlusion. Technical points pertinent to this case are clearly illustrated, including the sheathless approach and the use of a double wire strategy, one advanced ante-gradient and the other concomitantly advanced retro-gradient..

Impaired coronary and myocardial flow in severe aortic stenosis is associated with increased apoptosis: a transthoracic Doppler and myocardial contrast echocardiography study.

OBJECTIVE: To test the hypothesis that impaired coronary and myocardial blood flow are linked with increased myocyte apoptosis, thus establishing a link between pressure overload and left ventricular (LV) remodelling. METHODS AND RESULTS: Peak diastolic coronary blood flow velocity (CBFV) was evaluated at transthoracic Doppler echocardiography, and signal intensity (SI) and the rate of SI rise (beta) were measured at myocardial contrast echocardiography in 11 patients with severe aortic stenosis and LV hypertrophy. In the same patients, biopsies were obtained from the anterolateral LV free wall during surgery and analysed for cardiomyocyte apoptosis. LV mass corrected CBFV (CBFVI) was significantly lower in patients than in controls (median 0.100 cm.g/s (interquartile range 0.07-0.115) v 0.130 cm.g/s (0.130-0.160), p = 0.002). Similarly, SI*beta was significantly lower in patients than in controls (11 1/s (8-66) v 83 1/s (73-95), p = 0.001). Apoptotic rate was increased in aortic stenosis more than 100-fold versus controls (1.2% (0.8-1.4) v 0.01% (0.01-0.01), p < 0.001) and inversely correlated with lower CBFVI and SI*beta (r = -0.77, p = 0.001 for both). CONCLUSIONS: Patients with severe aortic stenosis and LV hypertrophy have impaired myocardial perfusion, which is associated with enhanced cardiomyocyte apoptosis. Impaired myocardial perfusion and the ensuing oxygen demand-supply imbalance may, at least partially, be responsible for increased apoptosis and possible transition to heart failure, thus establishing a link between pressure overload, LV remodelling, and heart failure.

Applying intravascular ultrasound to optimize the placement of coronary drug-eluting stents.

Intravascular ultrasound (IVUS) has provided in the last 2 decades major insights into the pathophysiology of coronary artery disease, and the mechanisms of action of percutaneous revascularization devices, helping the widespread adoption of coronary stents. The introduction of drug-eluting stents (DES) has recently lead to a revolution in the field of interventional cardiology, by virtually eliminating restenosis in selected low-risk lesions and significantly reducing both restenosis and repeat revascularizations in higher risk lesions. At the moment, the role of IVUS in the DES era is not well defined. Clinical studies utilizing IVUS in DES implantation used this technology mainly to evaluate the endpoint of intimal hyperplasia and to study the problem of incomplete apposition. On a theoretical basis, a method able to better evaluate optimal placement of a local drug delivery system should have a high rationale. Despite this sound preamble, no specific investigation has been conducted to evaluate the clinical need and possible advantage of routine IVUS for DES implantation and uncertainty is still present. A major hindrance lays in the low incidence of restenosis in most randomized trials enrolling few selected lesions per patient, as this fact enlarges the number of patients who need to be treated to demonstrate a benefit and casts doubts on the cost effectiveness of a more expensive and time consuming approach. The situation is bound to change when more complex patients and lesions are being treated, a setting associated with a higher event rate even when DES are used. While waiting for a prospective study addressing such issue, we can only rely on indirect evidence to justify and support the usage of IVUS in complex clinical settings with implantation of DES.

Surviving acute myocardial infarction: survivin expression in viable cardiomyocytes after infarction.

BACKGROUND: Apoptosis is a key feature in postinfarction remodelling leading to progressive myocyte loss. Both proapoptotic and antiapoptotic factors contribute to the delicate balance between death and survival. The survivin pathway has emerged as essential in the control of apoptosis, although its role in heart disease is unknown. AIM: To evaluate survivin expression after acute myocardial infarction (AMI). METHODS: Survivin expression was assessed immunohistochemically in the peri-infarct and remote viable myocardium in 17 consecutive patients who died 1-30 weeks after AMI and in four control hearts. RESULTS: Survivin was expressed by myocytes in the peri-infarct area in eight patients and in the remote region in 13 patients. The rate of survivin expression after AMI was significantly higher in the remote versus peri-infarct regions and compared with control hearts. Its expression was inversely associated with the presence of dilated cardiopathy and of apoptosis, independently from the gross pathology infarct size. CONCLUSIONS: Survivin myocardial expression after AMI may be associated with the survival of at risk myocardium and may be indicative of more favourable remodelling after AMI. These findings identify a potential new target for the treatment of postinfarction remodelling.

Increased mortality after coronary stenting in patients treated with clopidogrel without loading dose. Evidence from a meta-analysis.

AIM: Clopidogrel is an established alternative to ticlopidine in addition to aspirin after coronary stenting because of its hematologic safety, but its efficacy in comparison to ticlopidine is debated. We thus systematically reviewed randomized trials comparing clopidogrel vs ticlopidine after coronary stenting. METHODS: Medline (1/1986-10/2003), BioMed Central, Central, Current Contents, LILACS and mRCT were searched. Fixed-effect relative risks (RR [95% CI]) were computed, and the primary end-point was death. Heterogeneity tests and subgroup analyses were performed according to loading vs non-loading clopidogrel scheme. RESULTS: Five trials were retrieved (2 962 patients, average follow-up 7.4 months). In 3 studies both clopidogrel and ticlopidine were started with a loading dose, in 1 trial clopidogrel was administered without loading, and in 1 trial clopidogrel could be administered with or without loading. Overall analysis (p for heterogeneity=0.12) showed a non-significant trend toward increased mortality in patients treated with clopidogrel (38/1 649 [2.3%]) vs ticlopidine (22/1 313 [1.7%], RR=1.64 [0.94-2.86], p=0.080). After stratification, clopidogrel with loading was associated with non-significantly lower mortality rates than ticlopidine (9/959 [0.9%] vs 13/798 [1.6%], RR=0.68 [0.29-1.63], p=0.39). Instead, clopidogrel without any loading yielded a highly significantly 3-fold increased risk of death than ticlopidine (29/690 [4.2%] vs 9/515 [1.7%], RR=2.9 [1.45-6.1], p=0.0029). Similar results were obtained for the rate of death or non-fatal myocardial infarction. CONCLUSION: This meta-analysis suggests that clopidogrel treatment including a loading regimen is equivalent or may even be superior to ticlopidine after coronary stenting. However, current evidence shows conversely that clopidogrel therapy in the absence of a loading dose is associated with a significantly higher risk of death or myocardial infarction.

Cyclo-oxygenase-2 (COX-2) expression at the site of recent myocardial infarction: friend or foe?

BACKGROUND: Cyclo-oxygenase-2 (COX-2) is induced in cardiomyocytes only in response to stress, such as ischaemia. OBJECTIVE: To assess COX-2 expression at the site of recent myocardial infarction. METHODS: COX-2 expression was evaluated by specific immunostaining in cardiomyocytes from 23 subjects who died 10-60 days after acute myocardial infarction. The relation between COX-2 myocardial expression and apoptotic rate was investigated. Cardiomyocyte apoptotic rate was defined as the number of cells co-expressing in situ end labelling of DNA fragmentation (TUNEL) and immunostaining for activated caspase-3. RESULTS: COX-2 expression was found in cardiomyocytes at the site of infarction in nine of 23 cases (39%). It was associated with fivefold higher apoptotic rates (median 17.9% (interquartile range 11.0-25.4%) v 3.7% (0.6-12.8%); p = 0.016), and apoptotic rate increased progressively from mild to intense COX-2 staining (p for trend 0.009). COX-2 expression co-localised with TUNEL nuclear staining in myocytes, and there was a high concordance between COX-2 and hypoxia induced factor 1-alpha staining (78%, p = 0.021) and between COX-2 and bax (83%, p = 0.014). Subjects showing myocardial COX-2 expression were more likely to have enlarged hearts (p = 0.050), and intense COX-2 staining was strictly associated with symptomatic heart failure (p = 0.035). CONCLUSIONS: COX-2 is expressed in cardiomyocytes in nearly 40% of cases at the site of recent acute myocardial infarction, even late after the index event. Its expression was associated with extremely high apoptotic rates. These findings suggest a potential cause-effect link between COX-2 expression and enhanced myocardial apoptosis in ischaemic cardiomyopathy.