Angela Migliorini

High Residual Platelet Reactivity After Clopidogrel Loading and Long-term Cardiovascular Events Among Patients With Acute Coronary Syndromes Undergoing PCI

CONTEXT High residual platelet reactivity (HRPR) in patients receiving clopidogrel has been associated with high risk of ischemic events after percutaneous coronary intervention (PCI). OBJECTIVE To test the hypothesis that HRPR after clopidogrel loading is an independent prognostic marker of risk of long-term thrombotic events in patients with acute coronary syndromes (ACS) undergoing an invasive procedure and antithrombotic treatment adjusted according to the results of platelet function tests. DESIGN, SETTING, AND PATIENTS Prospective, observational, referral center cohort study of 1789 consecutive patients with ACS undergoing PCI from April 2005 to April 2009 at the Division of Cardiology of Careggi Hospital, Florence, Italy, in whom platelet reactivity was prospectively assessed by light transmittance aggregometry. INTERVENTIONS All patients received 325 mg of aspirin and a loading dose of 600 mg of clopidogrel followed by a maintenance dosage of 325 mg/d of aspirin and 75 mg/d of clopidogrel for at least 6 months. Patients with HRPR as assessed by adenosine diphosphate test (≥70% platelet aggregation) received an increased dose of clopidogrel (150-300 mg/d) or switched to ticlopidine (500-1000 mg/d) under adenosine diphosphate test guidance. MAIN OUTCOME MEASURES The primary end point was a composite of cardiac death, myocardial infarction, any urgent coronary revascularization, and stroke at 2-year follow-up. Secondary end points were stent thrombosis and each component of the primary end point. RESULTS The primary end point event rate was 14.6% (36/247) in patients with HRPR and 8.7% (132/1525) in patients with low residual platelet reactivity (absolute risk increase, 5.9%; 95% CI, 1.6%-11.1%; P = .003). Stent thrombosis was higher in the HRPR group compared with the low residual platelet reactivity group (6.1% [15/247] vs 2.9% [44/1525]; absolute risk increase, 3.2%; 95% CI, 0.4%-6.7%; P = .01). By multivariable analysis, HRPR was independently associated with the primary end point (hazard ratio, 1.49; 95% CI, 1.08-2.05; P = .02) and with cardiac mortality (hazard ratio, 1.81; 95% CI, 1.18-2.76; P = .006). CONCLUSION Among patients receiving platelet reactivity-guided antithrombotic medication after PCI, HRPR status was significantly associated with increased risk of ischemic events at short- and long-term follow-up. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01231035.

Comparison of Prasugrel and Ticagrelor Loading Doses in ST-Segment Elevation Myocardial Infarction Patients RAPID (Rapid Activity of Platelet Inhibitor Drugs) Primary PCI Study

OBJECTIVES This study sought to compare the action of prasugrel and ticagrelor in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI). BACKGROUND It has been documented that prasugrel and ticagrelor are able to provide effective platelet inhibition 2 h after a loading dose (LD). However, the pharmacodynamic measurements after prasugrel and ticagrelor LD have been provided by assessing only healthy volunteers or subjects with stable coronary artery disease. METHODS Fifty patients with STEMI undergoing PPCI with bivalirudin monotherapy were randomized to receive 60 mg prasugrel LD (n = 25) or 180 mg ticagrelor LD (n = 25). Residual platelet reactivity was assessed by VerifyNow at baseline and 2, 4, 8, and 12 h after LD. RESULTS Platelet reactivity units (PRU) 2 h after the LD (study primary endpoint) were 217 (12 to 279) and 275 (88 to 305) in the prasugrel and ticagrelor groups, respectively (p = NS), satisfying pre-specified noninferiority criteria. High residual platelet reactivity (HRPR) (PRU ≥240) was found in 44% and 60% of patients (p = 0.258) at 2 h. The mean time to achieve a PRU <240 was 3 ± 2 h and 5 ± 4 h in the prasugrel and ticagrelor groups, respectively. The independent predictors of HRPR at 2 h were morphine use (odds ratio: 5.29; 95% confidence interval: 1.44 to 19.49; p = 0.012) and baseline PRU value (odds ratio: 1.014; 95% confidence interval: 1.00 to 1.03; p = 0.046). CONCLUSIONS In patients with STEMI, prasugrel showed to be noninferior as compared with ticagrelor in terms of residual platelet reactivity 2 h after the LD. The 2 drugs provide an effective platelet inhibition 2 h after the LD in only a half of patients, and at least 4 h are required to achieve an effective platelet inhibition in the majority of patients. Morphine use is associated with a delayed activity of these agents. (Rapid Activity of Platelet Inhibitor Drugs Study, NCT01510171).

Impact of complete revascularization with percutaneous coronary intervention on survival in patients with at least one chronic total occlusion

AIMS This study sought to determine the impact on survival of successful drug-eluting stent-supported percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). METHODS AND RESULTS Comparison of long-term cardiac survival of consecutive patients who underwent PCI for at least one CTO and who were stratified into successful and failure procedures. From 2003 to 2006, 486 patients underwent PCI for 527 CTO. CTO-PCI was successful in 344 patients (71%) and 361 lesions (68%). Multivessel PCI was performed in 62% in the CTO-PCI failure group and in 71% in the CTO-PCI success group (P = 0.062). Cardiac survival rate was higher in the CTO-PCI success group compared with CTO-PCI failure group (91.6 +/- 2.0 vs. 87.4 +/- 2.9%; P = 0.025), in patients with multivessel disease and CTO-PCI success compared with CTO-PCI failure (91.4 +/- 2.2 vs. 86.6 +/- 3.1%; P = 0.021), and in patients with complete revascularization when compared to patients with incomplete revascularization (94.0 +/- 1.7 vs. 83.8 +/- 3.6%; P < 0.001). CONCLUSION Successful CTO-PCI confers a long-term survival benefit. Improvement in survival is driven by the differences in the outcome of patients with multivessel disease and who were completely revascularized.

A collaborative systematic review and meta-analysis on 1278 patients undergoing percutaneous drug-eluting stenting for unprotected left main coronary artery disease ☆

BACKGROUND Cardiac surgery is the standard treatment for unprotected left main disease (ULM). Drug-eluting stent (DES) implantation has been recently reported in patients with ULM but with unclear results. We systematically reviewed outcomes of percutaneous DES implantation in ULM. METHODS Several databases were searched for clinical studies reporting on > or = 20 patients and > or = 6-month follow-up. The primary end point was major adverse cardiovascular events (MACEs; ie, death, myocardial infarction, or target vessel revascularization [TVR]) at the longest follow-up. Incidence and adjusted risk estimates were pooled with generic inverse variance random-effect methods (95% CIs). RESULTS From 823 initial citations, 16 studies were included (1278 patients, median follow-up 10 months). Eight were uncontrolled registries, 5 nonrandomized comparisons between DES and bare-metal stents and 3 nonrandomized comparisons between DES and CABG, with no properly randomized trial. Meta-analysis for DES-based PCI showed, at the longest follow-up, rates of 16.5% (11.7%-21.3%) MACE, 5.5% (3.4%-7.7%) death, and 6.5% (3.7%-9.2%) TVR. Comparison of DES versus bare-metal stent disclosed adjusted odds ratios for MACE of 0.34 (0.16-0.71), and DES versus CABG showed adjusted odds ratios for MACE plus stroke of 0.46 (0.24-0.90). Meta-regression showed that disease location predicted MACE (P = .001) and TVR (P = .020), whereas high-risk features predicted death (P = .027). CONCLUSIONS Clinical studies report apparently favorable early and midterm results in selected patients with ULM. However, given their limitations in validity and the inherent risk for DES thrombosis, results from randomized trials are still needed to definitely establish the role of DES implantation instead of the reference treatment, surgery.

Abciximab-Supported Infarct Artery Stent Implantation for Acute Myocardial Infarction and Long-Term Survival A Prospective, Multicenter, Randomized Trial Comparing Infarct Artery Stenting Plus Abciximab With Stenting Alone

Background—The impact on survival of routine use of abciximab as adjunctive treatment to routine infarct artery stenting for acute myocardial infarction is not defined. We sought to determine the effect of abciximab on 1-year survival and other major adverse cardiac events of patients with acute myocardial infarction undergoing routine infarct artery stenting. Methods and Results—The Abciximab and Carbostent Evaluation (ACE) Trial is an unblinded, randomized, controlled trial that compared abciximab with placebo in patients undergoing routine infarct artery stent implantation for acute myocardial infarction. At 1 year, the survival rate was 95±2% in the abciximab group and 88±2% in the stent-alone group (P =0.017). The reinfarction rate was 1% in the abciximab group and 6.0% in the stent-alone group, whereas there were no differences between groups in target vessel revascularization rate (16.5% in the abciximab group, 17.5% in the stent-alone group). Conclusions—Abciximab as adjunctive treatment to routine infarct artery stenting for acute myocardial infarction resulted in improved 1-year survival and lower reinfarction rates.

Comparison of AngioJet rheolytic thrombectomy before direct infarct artery stenting with direct stenting alone in patients with acute myocardial infarction. The JETSTENT trial.

OBJECTIVES The aim of this study was to determine whether rheolytic thrombectomy (RT) before direct infarct artery stenting as compared with direct stenting (DS) alone results in improved myocardial reperfusion and clinical outcome in patients with acute myocardial infarction. BACKGROUND The routine removal of thrombus before infarct artery stenting is still a matter of debate. METHODS This is a multicenter, international, randomized, 2-arm, prospective study. Eligible patients were patients with acute myocardial infarction, angiographic evidence of thrombus grade 3 to 5, and a reference vessel diameter ≥2.5 mm. Coprimary end points were early ST-segment resolution and (99m)Tc-sestamibi infarct size. An α value = 0.05 achieved by both coprimary surrogate end points or an α value = 0.025 for a single primary surrogate end point would be considered evidence of statistical significance. Other surrogate end points were Thrombolysis In Myocardial Infarction (TIMI) flow grade 3, corrected TIMI frame count, and TIMI grade 3 blush. Clinical end points were a composite of major adverse cardiovascular events at 1, 6, and 12 months. RESULTS From December 2005 to September 2009, 501 patients were randomly allocated to RT before DS or to DS alone. The ST-segment resolution was more frequent in the RT arm as compared with the DS alone arm: 85.8% and 78.8%, respectively (p = 0.043), while no difference between groups were revealed in the other surrogate end points. The 6-month major adverse cardiovascular events rate was 11.2% in the thrombectomy arm and 19.4% in the DS alone arm (p = 0.011). The 1-year event-free survival rates were 85.2 ± 2.3% for the RT arm, and 75.0 ± 3.1% for the DS alone arm (p = 0.009). CONCLUSIONS Although the primary efficacy end points were not met, the results of this study support the use of RT before infarct artery stenting in patients with acute myocardial infarction and evidence of coronary thrombus. (AngioJet Rheolytic Thrombectomy Before Direct Infarct Artery Stenting in Patients Undergoing Primary PCI for Acute Myocardial Infarction [JETSTENT]; NCT00275990).

Cardiac Growth Factors in Human Hypertrophy Relations With Myocardial Contractility and Wall Stress

The aim of the present study was to investigate whether and which cardiac growth factors are involved in human hypertrophy, whether growth factor synthesis is influenced by overload type and/or by the adequacy of the hypertrophy, and the relationships between cardiac growth factor formation and ventricular function. Cardiac growth factor formation was assessed by measuring aorta-coronary sinus concentration gradient in patients with isolated aortic stenosis (n=26) or regurgitation (n=15) and controls (n=12). Gene expression and cellular localization was investigated in ventricular biopsies using reverse transcriptase-polymerase chain reaction and in situ hybridization. Cardiac hypertrophy with end-systolic wall stress <90 kdyne/cm2 was associated with a selective increased formation of insulin-like growth factor (IGF)-I in aortic regurgitation and of IGF-I and endothelin (ET)-1 in aortic stenosis. mRNA levels for IGF-I and preproET-1 were elevated and mainly expressed in cardiomyocytes. At stepwise analysis, IGF-I formation was correlated to the mean velocity of circumferential fiber shortening (r=0.86, P<0.001) and ET-1 formation to relative wall thickness (r=0.82, P<0. 001). When end-systolic wall stress was >90 kdyne/cm2, IGF-I and ET-1 synthesis by cardiomyocytes was no longer detectable, and only angiotensin (Ang) II was generated, regardless of the type of overload. The mRNA level for angiotensinogen was high, and the mRNA was exclusively expressed in the interstitial cells. Ang II formation was positively correlated to end-systolic stress (r=0.89, P<0.001) and end-diastolic stress (r=0.84, P<0.001). Multivariate stepwise analysis selected end-systolic stress as the most predictive variable and left ventricular end-diastolic pressure as the independent variable for Ang II formation (r=0.93, P<0.001). In conclusion, the present results indicate that the course of human left ventricular hypertrophy is characterized by the participation of different cardiac growth factors that are selectively related both to the type of hemodynamic overload and to ventricular function.

High Residual Platelet Reactivity After Clopidogrel Loading and Long-Term Clinical Outcome After Drug-Eluting Stenting for Unprotected Left Main Coronary Disease

Background— No data exist about the impact of high residual platelet reactivity (HRPR) after clopidogrel loading on long-term clinical outcome in patients undergoing drug-eluting stent (DES) implantation for unprotected left main disease (ULMD). Methods and Results— Consecutive patients who underwent percutaneous coronary intervention for ULMD had prospective platelet reactivity assessment by light transmittance aggregometry after a loading dose of 600 mg of clopidogrel. The primary end point of the study was cardiac mortality, and the secondary end point was stent thrombosis. From January 2005 to September 2008, 215 consecutive patients were treated with DES for ULMD. The incidence of HRPR after clopidogrel loading was 18.6%. The median follow-up was 19.3 months. The overall estimated 1-, 2- and 3-year cardiac mortality rate was 3.9±1.3%, 7.5±2.2%, and 12.2±3.4%, respectively. The 3-year cardiac mortality rate was 8.0±3.1% in the low residual platelet reactivity (LRPR) group and 28.3±10.4% in the HRPR group (P=0.005). The 3-year stent thrombosis rate was 4.2±1.8% in the low residual platelet reactivity group and 16.0±7.3% in the HRPR group (P=0.021). By forward stepwise regression analysis, HRPR after clopidogrel loading was the only independent predictor of cardiac death (hazard ratio, 3.82; 95% confidence interval,1.38 to 10.54; P=0.010) and stent thrombosis (hazard ratio, 3.69; 95% confidence interval, 1.12 to 12.09; P=0.031). Conclusions— HRPR after 600-mg clopidogrel loading is a strong marker of increased risk of cardiac death and DES thrombosis in patients receiving DES stenting for ULMD. Routine assessment of in vitro residual platelet reactivity after clopidogrel loading in patients with ULMD potentially suitable for DES-supported percutaneous coronary intervention should be considered to guide patient care decisions.

Relation between preintervention angiographic evidence of coronary collateral circulation and clinical and angiographic outcomes after primary angioplasty or stenting for acute myocardial infarction

It is unknown if collateral circulation (CC) has a beneficial effect on outcomes of patients who undergo mechanical intervention in the first hours after onset of acute myocardial infarction (AMI). This study analyzes the relation between CC and outcome in patients with AMI who underwent primary angioplasty or stenting within 6 hours of symptom onset. The analysis was performed in a series of 1,164 consecutive patients. The contribution of clinical, angiographic, and procedural variables to the angiographic and clinical outcomes was evaluated by multivariate logistic regression analysis and the Cox proportional hazard model, respectively. Of 1,164 patients, 264 (23%) had angiographic evidence of CC. Patients with CC had a lower incidence of diabetes (11% vs 16%, p = 0.033), anterior AMI (41% vs 55%, p <0.001), cardiogenic shock (9% vs 14%, p = 0.029), anterograde TIMI grade flow >1 (10% vs 21%, p <0.001), and a greater incidence of preinfarction angina (43% vs 32%, p = 0.001), multivessel disease (59% vs 47%, p = 0.001), and total chronic occlusion (20% vs 10%, p <0.001). At 6 months, the mortality rate was lower in patients with CC compared with patients without CC (4% vs 9%, p = 0.011), whereas there were no differences in the incidence of reinfarction, target vessel revascularization, and angiographic restenosis. After multivariate analysis, CC did not emerge as a significant variable in relation to 6-month clinical and angiographic outcomes. CC does not exert a protective effect in patients who undergo mechanical intervention in the first 6 hours of AMI onset.

Predictors of Reocclusion After Successful Drug-Eluting Stent–Supported Percutaneous Coronary Intervention of Chronic Total Occlusion

OBJECTIVES This study sought to assess the incidence of reocclusion and identification of predictors of angiographic failure after successful chronic total occlusion (CTO) drug-eluting stent-supported percutaneous coronary intervention (PCI). BACKGROUND Large registries have shown a survival benefit in patients with successful CTO PCI. Intuitively, sustained vessel patency may be considered as a main variable related to long-term survival. Very few data exist about the angiographic outcome after successful CTO PCI. METHODS The Florence CTO PCI registry started in 2003 and included consecutive patients treated with drug-eluting stents for at least 1 CTO (>3 months). The protocol treatment included routine 6- to 9-month angiographic follow-up. Clinical, angiographic, and procedural variables were included in the model of multivariable binary logistic regression analysis for the identification of the predictors of reocclusion. RESULTS From 2003 to 2010, 1,035 patients underwent PCI for at least 1 CTO. Of these, 802 (77%) had a successful PCI. The angiographic follow-up rate was 82%. Reocclusion rate was 7.5%, whereas binary restenosis (>50%) or reocclusion rate was 20%. Everolimus-eluting stents were associated with a significantly lower reocclusion rate than were other drug-eluting stents (3.0% vs. 10.1%; p = 0.001). A successful subintimal tracking and re-entry technique was associated with a 57% of reocclusion rate. By multivariable analysis, the subintimal tracking and re-entry technique (odds ratio [OR]: 29.5; p < 0.001) and everolimus-eluting stents (OR: 0.22; p = 0.001) were independently related to the risk of reocclusion. CONCLUSIONS Successful CTO-PCI supported by everolimus-eluting stents is associated with a very high patency rate. Successful subintimal tracking and re-entry technique is associated with a very low patency rate regardless of the type of stent used.