F13A1 Gene Variant (V34L) and Residual Circulating FXIIIA Levels Predict Short- and Long-Term Mortality in Acute Myocardial Infarction after Coronary Angioplasty.

Factor XIIIA (FXIIIA) levels are independent predictors of early prognosis after acute myocardial infarction (AMI) and the Valine-to-Leucine (V34L) single nucleotide polymorphism (SNP) seems associated with lower AMI risk. Since the long-term AMI prognosis merits deeper investigation, we performed an observational study evaluating relationships between FXIIIA residual levels, cardiovascular risk-factors, and inherited genetic predispositions. FXIIIA V34L was genotyped in 333 AMI patients and a five-year follow-up was performed. FXIIIA levels assessed at day-zero (d0) and four days after AMI (d4), and conventional risk factors were analyzed, focusing on the development of major adverse cardiovascular events (MACE). FXIIIA assessed at d0 and d4 was also an independent MACE predictor in the long-term follow-up (FXIIIAd0, Odds Ratio (OR) = 3.02, 1.79⁻5.1, p = 0.013; FXIIIAd4, OR = 4.46, 2.33⁻8.55, p = 0.0001). FXIIIAd4 showed the strongest MACE association, suggesting that the FXIIIA protective role is maximized when high levels are maintained for longer time. Conversely, FXIIIA levels stratified by V34L predicted MACE at a lesser extent among L34-carriers (Hazard Risk (HR)VV34 = 3.89, 2.19⁻6.87, p = 0.000003; HRL34-carriers = 2.78, 1.39⁻5.57, p = 0.0039), and V34L did not predict all MACE, only multiple-MACE occurrence (p = 0.0087). Finally, in survival analysis, heart failure and death differed significantly from stroke and recurrent ischemia (p = 0.0013), with FXIIIA levels appreciably lower in the former (p = 0.05). Overall, genetically-determined FXIIIA levels have a significant long-term prognostic role, suggesting that a pharmacogenetics approach might help to select those AMI patients at risk of poor prognosis in the need of dedicated treatments.

Tirofiban and sirolimus-eluting stent vs abciximab and bare-metal stent for acute myocardial infarction: a randomized trial.

CONTEXT: Bare-metal stenting with abciximab pretreatment is currently considered a reasonable reperfusion strategy for acute ST-segment elevation myocardial infarction (STEMI). Sirolimus-eluting stents significantly reduce the need for target-vessel revascularization (TVR) vs bare-metal stents but substantially increase procedural costs. At current European list prices, the use of tirofiban instead of abciximab would absorb the difference in cost between stenting with sirolimus-eluting vs bare-metal stents. OBJECTIVE: To evaluate the clinical and angiographic impact of single high-dose bolus tirofiban plus sirolimus-eluting stenting vs abciximab plus bare-metal stenting in patients with STEMI. DESIGN, SETTING, AND PATIENTS: Prospective, single-blind, randomized controlled study (Single High Dose Bolus Tirofiban and Sirolimus Eluting Stent vs Abciximab and Bare Metal Stent in Myocardial Infarction [STRATEGY]) of 175 patients (median age, 63 [interquartile range, 55-72] years) presenting to a single referral center in Italy with STEMI or presumed new left bundle-branch block and randomized between March 6, 2003, and April 23, 2004. INTERVENTION: Single high-dose bolus tirofiban regimen plus sirolimus-eluting stenting (n = 87) vs standard-dose abciximab plus bare-metal stenting (n = 88). MAIN OUTCOME MEASURES: The primary end point was a composite of death, nonfatal myocardial infarction, stroke, or binary restenosis at 8 months. Secondary outcomes included freedom, at day 30 and month 8, from major cardiac or cerebrovascular adverse events (composite of death, reinfarction, stroke, and repeat TVR). RESULTS: Cumulatively, 14 of 74 patients (19%; 95% confidence interval [CI], 10%-28%) in the tirofiban plus sirolimus-eluting stent group and 37 of 74 patients (50%; 95% CI, 44%-56%) in the abciximab plus bare-metal stent group reached the primary end point (hazard ratio, 0.33; 95% CI, 0.18-0.60; P<.001 [P<.001 by Fischer exact test]). The cumulative incidence of death, reinfarction, stroke, or TVR was significantly lower in the tirofiban plus sirolimus-eluting stent group (18%) vs the abciximab plus bare-metal stent group (32%) (hazard ratio, 0.53; 95% CI, 0.28-0.92; P = .04), predominantly reflecting a reduction in the need for TVR. Binary restenosis was present in 6 of 67 (9%; 95% CI, 2%-16%) and 24 of 66 (36%; 95% CI, 26%-46%) patients in the tirofiban plus sirolimus-eluting stent and abciximab plus bare-metal stent groups, respectively (P = .002). CONCLUSION: Tirofiban-supported sirolimus-eluting stenting of infarcted arteries holds promise for improving outcomes while limiting health care expenditure in patients with myocardial infarction undergoing primary intervention.

Factor XIII-A dynamics in acute myocardial infarction: a novel prognostic biomarker?

After acute myocardial infarction (MI) the damaged heart has to be repaired. Factor XIII (FXIII) is considered a key molecule in promoting heart healing. FXIII deficiency was associated to cardiac rupture and anomalous remodelling in MI. During MI, FXIII contributes firstly to the intracoronary thrombus formation and shortly after to heal the myocardial lesion. To quantify the real contribution of FXIII in this process, and to explore its possible prognostic role, we monitored the FXIII-A subunit levels in 350 acute MI patients during the first six days (d0-d5) plus a control at 30-60 days (d30). A one-year follow-up was performed for all the patients. A transient drop in the FXIII-A mean level was noted in the whole cohort of patients (FXIII-Ad0 99.48 ± 30.5 vs FXIII-Ad5 76.51 ± 27.02; p< 0.0001). Interestingly, those who developed post-MI heart failure showed the highest drop (FXIII-Ad5 52.1 ± 25.2) and they already presented with low levels at recruitment. Similarly, those who died showed the same FXIII-A dynamic (FXIII-Ad5 54.0 ± 22.5). Conversely, patients who remained free of major adverse cardiac events, had lower consuming (FXIII-Ad0 103.6 ± 29.1 vs FXIII-Ad5 84.4 ± 24.5; p< 0.0001). Interestingly, the FXIII-A drop was independent from the amount of injury assessed by TnT and CKMB levels. The survival analysis ascribed an increased probability of early death or heart failure inversely related to FXIII-A quartiles (FXIII-A25th< 59.5 %; hazard ratio 4.25; 2.2-5.1; p< 0.0001). Different FXIII-A dynamics and levels could be utilised as early prognostic indicators during acute MI, revealing the individual potential to heal and suggesting tailored treatments to avoid heart failure or its extreme consequence.

Use of granulocyte-colony stimulating factor during acute myocardial infarction to enhance bone marrow stem cell mobilization in humans: clinical and angiographic safety profile.

AIMS: There is increasing evidence that stem cell (SC) mobilization to the heart and their differentiation into cardiac cells is a naturally occurring process. We sought to assess the safety and feasibility of granulocyte-colony stimulating factor (G-CSF) administration in humans to enhance SC mobilization and left ventricle (LV) injury repair during myocardial infarction (MI). METHODS AND RESULTS: Twenty patients with STEMI (mean age, 61+/-10 years), of whom 14 were submitted to primary percutaneous coronary intervention, were randomized to G-CSF (5 microg/kg/day s.c. for 4 consecutive days) or placebo. At entry and then at months 3 and 6, (99m)Tc-sestamibi gated-SPECT was performed to estimate extension of perfusion defect (PD) and LV function. The study drug was well tolerated and induced a significant increase of white blood count, CD34(+) cells, and CD34(+) cells coexpressing AC133 and VEGFR-2. At follow-up, treated and placebo groups did not differ for the angiographic coronary late loss and showed a similar pattern of PD recovery, whereas in the former at 6 months LVEF and especially LVEDV tended to be relatively higher (P=0.068) and lower (P=0.054), respectively. CONCLUSION: G-CSF administration in acute MI patients was feasible and did not lead to any clinical or angiographic adverse events and resulted in CD34(+) and CD34(+)AC133(+)VEGFR2(+) cell mobilization.

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.

BACKGROUND: 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.