Gianfranco Percoco

Comparison of Angioplasty With Infusion of Tirofiban or Abciximab and With Implantation of Sirolimus-Eluting or Uncoated Stents for Acute Myocardial Infarction: The MULTISTRATEGY Randomized Trial

CONTEXT Abciximab infusion and uncoated-stent implantation is a complementary treatment strategy to reduce major adverse cardiac events in patients undergoing angioplasty for ST-segment elevation myocardial infarction (STEMI). It is uncertain whether there may be similar benefits in replacing abciximab with high-dose bolus tirofiban. Similarly, the use of drug-eluting stents in this patient population is currently discouraged because of conflicting results on efficacy reported in randomized trials and safety concerns reported by registries. OBJECTIVE To evaluate the effect of high-dose bolus tirofiban and of sirolimus-eluting stents as compared with abciximab infusion and uncoated-stent implantation in patients with STEMI undergoing percutaneous coronary intervention. DESIGN, SETTING, AND PATIENTS An open-label, 2 x 2 factorial trial of 745 patients presenting with STEMI or new left bundle-branch block at 16 referral centers in Italy, Spain, and Argentina between October 2004 and April 2007. INTERVENTIONS High-dose bolus tirofiban vs abciximab infusion and sirolimus-eluting stent vs uncoated stent implantation. MAIN OUTCOME MEASURES For drug comparison, at least 50% ST-segment elevation resolution at 90 minutes postintervention with a prespecified noninferiority margin of 9% difference (relative risk, 0.89); for stent comparison, the rate of major adverse cardiac events, defined as the composite of death from any cause, reinfarction, and clinically driven target-vessel revascularization within 8 months. RESULTS ST-segment resolution occurred in 302 of 361 patients (83.6%) who had received abciximab infusion and 308 of 361 (85.3%) who had received tirofiban infusion (relative risk, 1.020; 97.5% confidence interval, 0.958-1.086; P < .001 for noninferiority). Ischemic and hemorrhagic outcomes were similar in the tirofiban and abciximab groups. At 8 months, major adverse cardiac events occurred in 54 patients (14.5%) with uncoated stents and 29 (7.8%) with sirolimus stents (P = .004), predominantly reflecting a reduction of revascularization rates (10.2% vs 3.2%). The incidence of stent thrombosis was similar in the 2 stent groups. CONCLUSIONS In patients with STEMI undergoing percutaneous coronary intervention, compared with abciximab, tirofiban therapy was associated with noninferior resolution of ST-segment elevation at 90 minutes following coronary intervention, whereas sirolimus-eluting stent implantation was associated with a significantly lower risk of major adverse cardiac events than uncoated stents within 8 months after intervention. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00229515.

Oxidative stress during myocardial ischaemia and heart failure.

Oxidative stress is a condition in which oxidant metabolites exert their toxic effect because of an increased production or an altered cellular mechanism of protection. The heart needs oxygen avidly and, although it has powerful defence mechanisms, it is susceptible to oxidative stress, which occurs, for instance, during post-ischaemic reperfusion. Ischaemia causes alterations in the defence mechanisms against oxygen free radicals, mainly a reduction in the activity of mitochondrial superoxide dismutase and a depauperation of tissue content of reduced glutathione. At the same time, production of oxygen free radicals increases in the mitochondria and leukocytes and toxic oxygen metabolite production is exacerbated by re-admission of oxygen during reperfusion. Oxidative stress, in turn, causes oxidation of thiol groups and lipid peroxidation leading first to reversible damage, and eventually to necrosis. In man, there is evidence of oxidative stress (determined by release of oxidised glutathione in the coronary sinus) during surgical reperfusion of the whole heart, or after thrombolysis, and it is related to transient left ventricular dysfunction or stunning. Data on oxidative stress in the failing heart are scant. It is not clear whether the defence mechanisms of the myocyte are altered or whether the production of oxygen free radicals is increased, or both. Recent data have shown a close link between oxidative stress and apoptosis. Relevant to heart failure is the finding that tumour necrosis factor, which is found increased in failing patients, induces a rapid rise in intracellular reactive oxygen intermediates and apoptosis. This series of events is not confined to the myocytes, but occurs also at the level of endothelium, where tumour necrosis factor causes expression of inducible nitric oxide synthase, production of the reactive radical nitric oxide, oxidative stress and apoptosis. It is therefore, possible that the immunological response to heart failure results in endothelial and myocyte dysfunction through oxidative stress mediated apoptosis. Clarification of these mechanisms may lead to novel therapeutic strategies.

Tumor Necrosis Factor-α Receptor 1 Is a Major Predictor of Mortality and New-Onset Heart Failure in Patients With Acute Myocardial Infarction The Cytokine-Activation and Long-Term Prognosis in Myocardial Infarction (C-ALPHA) Study

Background—Tumor necrosis factor alpha-&agr; (TNF-&agr;) activation is an independent prognostic indicator of mortality in patients with heart failure (HF). Despite the recognition that several TNF family cytokines are elevated during myocardial infarction, their role in predicting subsequent prognosis in these setting remains poorly understood. Methods and Results—We performed a systematic evaluation of TNF-&agr; and its type 1 and 2 soluble receptors, together with interleukin (IL)-6, IL-1 receptor antagonist, and IL-10, in 184 patients (132 men; mean age, 64±12) consecutively admitted for myocardial infarction. We correlated their values to short- and long-term incidence of death and HF (primary outcome). In 10 patients, we also studied the presence of transcardiac gradients for TNF-&agr; and its soluble receptors. The control group comprised 45 healthy subjects who were sex and age matched (33 men; mean age, 65±6 years) to the patients. All tested cytokines were increased in patients, and no transcardiac or systemic AV difference was found. After a median follow-up of 406 days (range, 346 to 696 days), 24 patients died and 32 developed HF. Univariate analysis showed that all cytokines were related to outcome, whereas after adjustment for baseline and clinical characteristics, sTNFR-1 remained the only independent predictor of death and HF (hazard ratio, 2.9; 95% CI, 1.9 to 3.8, tertile 1 versus 3), together with left ventricular ejection fraction, Killip class, and creatine kinase-MB at peak. Conclusions—sTNFR-1 is a major short- and long-term predictor of mortality and HF in patients with acute myocardial infarction.

Efficacy and safety of drug-eluting stents in ST-segment elevation myocardial infarction: a meta-analysis of randomized trials

BACKGROUND Recent concerns have emerged on the potential higher risk of stent thrombosis after DES implantation, that might be even more pronounced among STEMI patients. Thus, the aim of the current study was to perform a meta-analysis to evaluate the benefits and safety of DES as compared to BMS in patients undergoing primary angioplasty for STEMI. METHODS The literature was scanned by formal searches of electronic databases (MEDLINE and CENTRAL). We examined all completed randomized trials of DES for STEMI. The following key words were used for study selection: randomized trial, myocardial infarction, reperfusion, primary angioplasty, stenting, DES, sirolimus-eluting stent (SES), Cypher, paclitaxel-eluting stent (PES), Taxus. Information on study design, type of stent, inclusion and exclusion criteria, primary endpoint, number of patients, angiographic and clinical outcome, were extracted by two investigators. Disagreements were resolved by consensus. RESULTS A total of 11 trials were included in the meta-analysis, involving 3605 patients (1888 or 52.3% randomized to DES and 1719 or 47.7% randomized to BMS). At 12 months follow-up, no significant difference was observed in mortality (4.1% vs 4.4%, OR [95% CI]=0.91 [0.66-1.27], p=0.59, reinfarction (3.1% vs 3.4%, OR [95% CI]=0.85 [0.58, 1.23], p=0.38 or stent thrombosis (1.6% vs 2.2%, OR [95% CI]=0.76 [0.47, 1.23], p=0.22), whereas DES were associated with a significant reduction in TVR (5.0% vs 12.6%, OR [95% CI]=0.36 [0.28, 0.47], p<0.0001). Safety and efficacy of DES were confirmed at 18 to 24 months follow-up (data available from 4 trials including 1178 patients). CONCLUSIONS This meta-analysis shows that among selected STEMI patients undergoing primary angioplasty, SES and PES, as compared to BMS, are safe and associated with a significant reduction in TVR at 1 and 2 years follow-up.

Safety and Long-Term Efficacy of Sirolimus Eluting Stent in ST-elevation Acute Myocardial Infarction: The REAL (Registro REgionale AngiopLastiche Emilia-Romagna) Registry

SummaryBackground: Limited data are available for sirolimus eluting stent (SES) implantation in patients with ST-segment elevation myocardial infarction (STEMI). Aim: to confirm the safety and effectiveness of SES in patients with STEMI in a real-world scenario (multicentric registry). Methods: From July 2002 to June 2004, clinical and angiographic data of 1617 patients with STEMI treated with primary percutaneous coronary intervention (PCI) have been collected. Patients were prospectively followed for the occurrence of major adverse cardiac events (MACE): death, reinfarction and target vessel revascularization (TVR). Results: Overall, 205 patients received SES (12.5%, SES group) and 1412 received bare metal stent (87.5%, BMS group) in the infarct related artery. Compared with the BMS group, SES patients were younger, had more often diabetes mellitus, anterior localization and less cardiogenic shock at admission. The angiographic characteristics in the SES group showed longer lesions and smaller diameter of vessels. After a median follow-up of 396 days, there was no significant difference in the rate of stent thrombosis (1% in the SES group vs 1.5% in the BMS group, p=ns). The incidence of MACE was significantly lower in the SES group compared to BMS group (HR 0.62 [95% CI: 0.4–0.95]; p=0.03), principally due to the lower rate of TVR (HR 0.41 [95% CI: 0.2–0.85]; p=0.01). Conclusions: Utilization of SES in the setting of primary PCI for STEMI, in our “real world” registry, was safe and improved the 1-year clinical outcome compared to BMS reducing the need of TVR.

High-dose bolus tirofiban and sirolimus eluting stent versus abiciximab and bare metal stent in acute myocardial infarction (STRATEGY) study--protocol design and demography of the first 100 patients.

AbstractBackground: Primary bare metal stenting and abciximab infusion are currently considered the best available reperfusion strategy for acute ST-segment elevation myocardial infarction (STEMI). Sirolimus eluting stents (SES), compared to bare metal stent (BMS), greatly reduce the incidence of binary restenosis and target vessel revascularisation (TVR), but their use on a routine basis results in a significant increase in medical costs. With current European list prices, the use of tirofiban instead of abciximab would save enough money to absorb the difference between SES and BMS. Aim: To assess whether in patients with STEMI the combination of SES with high dose bolus (HDB) tirofiban results in a similar incidence of major cardiovascular events (MACE) but in a lower binary restenosis rate after six months compared to BMS and abciximab. Methods and Results: 160 patients are required to satisfy the primary composite end-point, including MACE and binary restenosis. The study is ongoing: the current paper focuses on the methodology and demography of the first 100 patients so far enrolled. Patients randomised to HDB tirofiban (n = 50, mean age: 62 ± 12, 40 males) and abciximab (n = 50, mean age: 63 ± 12, 38 males) do not differ for medical history, presentation profile, medications at discharge, angiographic profile and creatine-kinase MB-fraction at peak. Conclusions: The results of the trial will be available by the end of 2004: they will be crucial for the cardiologists to know whether the gold standard for AMI treatment should be reconsidered after the introduction of SES into the clinical practice.