Primary Percutaneous Coronary Intervention Strategy Research Articles

Duration of Symptoms Is Not Always the Key Modulator of the Choice of Reperfusion for ST-Elevation Myocardial Infarction

Fibrinolytic therapy (FT) and primary percutaneous coronary intervention (PCI) are both well-accepted reperfusion therapies in ST-segment elevation myocardial infarction (STEMI). The evidence of randomized clinical trials indicates a relatively modest difference in 30-day mortality (≈1%) in favor of primary PCI over fibrin-specific FT and was based on very timely primary PCI (ie, a primary PCI–related delay of 40 minutes [door-to-balloon less door-to-needle time]).1 Longer delays to primary PCI, which are far more frequent in clinical practice,2 are associated with attenuated benefit or no benefit at all, particularly when compared with fibrin-specific FT.3,4 The benefit of timely primary PCI over FT is likely to especially apply to higher-risk patients.5,6 Irrespective of the method of reperfusion, the potential for myocardial salvage and better clinical outcome is inversely proportional to ischemic time or its only available clinical surrogate, symptom duration.7–12 These considerations underpin the notion expressed in the American College of Cardiology/American Heart Association (ACC/AHA) guidelines on the treatment of STEMI that timely reperfusion therapy is likely more important in determining outcome than whether FT or primary PCI is the chosen reperfusion method.13 Response by Armstrong et al p 1310 The ACC/AHA STEMI guidelines highlight the time point of 3 hours of symptom duration in guiding the choice of reperfusion therapy. They state that if symptom duration is <3 hours, no preference exists between FT and primary PCI provided that treatment is timely (for FT, door-to-needle time <30 minutes; for primary PCI, door-to-balloon time <90 minutes and ≤60 minutes between estimated needle time and estimated balloon time). However, if symptom duration exceeds 3 hours, these guidelines favor primary PCI over FT, again provided that primary PCI can be performed in a timely fashion.13 This article reexamines the evidence that may or may not be the basis …

Gender differences in efficacy of primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction

The clinical outcome of percutaneous coronary intervention (PCI) is poorer in women than that in men. This study aimed at comparing the impact of gender difference on the strategy of primary PCI in patients with acute ST-segment elevation myocardial infarction (STEMI). Two hundred and fifty-nine patients with STEMI who underwent primary PCI within 12 hours of symptom onset were enrolled. The male group consisted of 143 men aged > 55 years, and a female group included 116 women without age limitation. Procedural success was defined as residual stenosis < 20% with thrombolysis in myocardial infarction flow grade > 2 and without death, emergency bypass surgery or disabling cerebral events during the hospitalization. The rate of major adverse cardiac events (MACE), including death, nonfatal myocardial infarction and target vessel revascularization during follow-up, was recorded. Female patients were more hypertensive and diabetic and with fewer cigarette smokers than male counterparts. The prevalence of angiographic 3-vessel disease was higher in the female group, but the procedural success rate was comparable between the two groups (94.4% vs 92.2%). The occurrence rate of MACE did not differ during the hospitalization (4.2% vs 6.0%, P = 0.50), but was significantly higher in the female group during follow-up (mean (16.0 +/- 11.2) months) than that in the male group (5.4% vs 0.7%, P = 0.02). Despite a similar success rate of primary PCI and in-hospital outcomes in both genders, female patients with acute STEMI still have a worse prognosis during the long-term follow-up.

PCI after lytic therapy: when and how?

Primary percutaneous coronary intervention (PCI) and thrombolysis are approved therapies in the treatment of ST-elevation myocardial infarction (STEMI). Many clinical trials have shown that primary PCI provides better results than thrombolysis for the STEMI treatment. However, the advantages of invasive approach over fibrinolytic therapy may be blunted by low availability of experienced centres offering 24 h/7 days primary PCI service and by delay to mechanical reperfusion due to prolonged transport. Current guidelines recommend that primary PCI should be performed by skilled professionals within less than 90 (120) min after first medical contact. In practice, these requirements prohibit a large number of STEMI patients from benefiting from primary PCI because of the lack of access to an established primary PCI centre at the site of first presentation and long anticipated interhospital transfer time. Many of them are treated with lytics and referred to angiography with subsequent PCI in different time mode. Current data support the strategy of immediate PCI after lytics than waiting for rescue PCI if lysis is non-effective. The purpose of this article is to review the current approaches to patients after fibrynolytic therapy referred for PCI for STEMI.

Intracoronary Administration of Abciximab in ST-Elevation Myocardial Infarction

Primary percutaneous coronary intervention (PCI) is now the preferred method of treating patients with ST-elevation myocardial infarction (STEMI). Despite restoration of epicardial flow, microvascular obstruction may persist after primary PCI as a result of both atheromatous and thrombotic embolization, neutrophil plugging, edema, and vasospasm.1–3 Therefore, studies such as the one by Thiele et al4 in this issue of Circulation that focus on the prevention and treatment of microvascular dysfunction are informative with respect to the means to improve the primary PCI strategy. Article p 49 There have been efforts to identify mechanical and pharmacological strategies to improve myocardial perfusion after primary PCI. Compared with the systemic administration of intravenous pharmacotherapies, highly localized administration of intracoronary pharmacotherapy may be associated with a several-hundred-fold increase in the local concentration of an agent in the epicardial artery and microcirculation. A number of pharmacotherapies, including adenosine,5,6 calcium channel blockers,7 α-blockers,8 β2-receptor activators,9 other vasodilators, antithrombotics,10,11 and antiplatelet agents,12–14 have been used to treat microvascular dysfunction. There are tens of thousands of glycoprotein IIb/IIIa (GPIIb/IIIa) receptors on the platelet surface.15 Platelet receptor occupancy studies have demonstrated that if there are fewer GPIIb/IIIa receptors free and available for cross-linking with fibrinogen, then myocardial perfusion is improved.16 To estimate the number of GPIIb/IIIa receptors available for cross-linking, the absolute platelet count has been multiplied by the percent of receptors available to cross link to calculate an index of the absolute number of GPIIb/IIIa receptors available. The absolute number of GPIIb/IIIa receptors available for cross-linking is reduced among patients with successful restoration of myocardial perfusion and ST-segment resolution in an STEMI population.16 Thus, the hypothesized mechanistic basis for intracoronary administration of GPIIb/IIIa inhibitors is that high …

Effectiveness of Primary Percutaneous Coronary Intervention for Acute ST-Elevation Myocardial Infarction from a 5-Year Single-Center Experience

Primary percutaneous coronary intervention (PCI) is currently viewed as the preferred reperfusion strategy in patients with ST-elevation acute myocardial infarction (STEMI). This method was introduced in our hospital in 2000. From January 1, 2000, to December 31, 2004, a total of 2,393 consecutive patients with STEMI were admitted (27% transferred from 9 non-PCI hospitals and 31 prehospital emergency units/outpatient clinics). Of these patients, 1,666 (70%) underwent urgent coronary angiography and primary PCI. Platelet glycoprotein llb/llla inhibitors were used in 40% and stent placement, in 78%. Postprocedural Thrombolysis In Myocardial Infarction (TIMI) 3 flow was documented in 86%. Intra-aortic balloon counterpulsation was used in 6%; mechanical ventilation, in 8.6%; and inotropic drugs/vasopressors, in 15.8%. Mortality rates in patients with Killip's class I or II ranged from 1% to 4.9% without negative influence of ischemic time. In patients with Killip's class III or IV, mortality rates increased from 18% to 54% with increasing ischemic delay up to 6 hours (p = 0.06) and remained at around 40% afterward. Independent predictors of mortality were age (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.01 to 1.64, p = 0.04), resuscitated cardiac arrest (OR 2.44, 95% CI 1.18 to 5.05, p = 0.02), and postprocedural TIMI flow (OR 0.31, 95% CI 0.16 to 0.59). Overall mortality rates of patients who underwent a primary PCI strategy from 2000 to 2004 were significantly lower than in the control group of 152 consecutive patients who underwent thrombolysis from 1995 to 1996 (6.2% vs 16.4%; p <0.001). In conclusion, introduction of a primary PCI strategy significantly decreased hospital mortality in our unselected group of patients with STEMI compared with the thrombolytic era. Our study further emphasized the importance of shortening myocardial ischemic time, particularly in the presence of severe heart failure on admission.

A Geospatial Analysis of Emergency Transport and Inter-Hospital Transfer in ST-Segment Elevation Myocardial Infarction

Primary percutaneous coronary intervention (PCI) yields better outcomes than thrombolytic therapy in the treatment of patients with ST-segment elevation myocardial infarctions (STEMIs). Emergency medical service systems are potentially important partners in efforts to expand the use of PCI. This study was conducted to explore the probable impact on patient mortality and hospital volumes of competing strategies for the emergency transport of patients with STEMIs. Emergency transport was simulated for 2,000 patients with STEMIs from the Atlantic Cardiovascular Patient Outcomes Research Team (C-PORT) trial in a geospatial model of Dallas County, Texas. Patient mortality estimates were obtained from a recently developed predictive model comparing PCI and thrombolytic therapy. A strategy of transporting patients to the closest hospital and treating with PCI if available and thrombolytic therapy if not yielded a 5.2% 30-day mortality rate (95% confidence interval [CI] 4.2% to 6.3%). A strategy of universal PCI, in which patients were transported only to PCI-capable hospitals, yielded 4.4% (95% CI 3.6% to 5.4%) mortality and an increase in patient volume at 2 full-time PCI hospitals of >1,000%. A strategy of targeted PCI, in which high-benefit patients were transported or transferred to PCI-capable hospitals, yielded 4.5% (95% CI 3.8% to 5.5%) mortality if transfers were decided in the emergency department and 4.2% (95% CI 3.4% to 5.1%) if transport was decided in the emergency vehicle. Targeted PCI strategies increased patient volumes at full-time PCI hospitals by about 700%. In conclusion, the selection of high-benefit patients for transport or transfer to PCI-capable hospitals can reduce mortality while minimizing major shifts in hospital patient volumes.

The incidence, treatment strategies and outcomes of acute coronary syndromes in the “reperfusion network” of different hospital types in the Czech Republic: Results of the Czech evaluation of acute coronary syndromes in hospitalized patients (CZECH) registry

Aims To analyze the incidence, treatment strategies and outcomes of acute coronary syndromes (ACS) in Czech population. Methods and results ACS diagnosis was confirmed in 1345 of 1921 (70%) consecutively admitted patients with suspected ACS. ACS incidence was 3248 cases/million/year and the annual incidence of confirmed myocardial infarction was 1960 per million. In-hospital mortality was 5.1% (10.0% with Q-MI, 4.4% with non-Q-MI, and 0.9% with UAP). Coronary angiography was performed in 92% of STEMI (followed by primary PCI in 83%, by CABG in 3%, by conservative therapy in 6%). Thrombolysis was used in only 1% of patients. Reperfusion therapy was thus used in 87% of all STEMI patients. Discharge medication included aspirin in 95%, a statin in 76%, a beta-blocker in 78%, an ACE inhibitor in 50%, clopidogrel in 60%, and ticlopidine in 4% of patients. Conclusions In-hospital mortality of ACS in the Czech network of PCI and non-PCI hospitals is low. Nationwide application of primary PCI strategy for STEMI is feasible and increases the overall use of reperfusion therapy.

Routine percutaneous coronary intervention in elderly patients with cardiogenic shock complicating acute myocardial infarction

Age is a strong predictor of cardiogenic shock (CS) and death in patients with acute myocardial infarction (AMI). Few data on the impact of a routine early percutaneous revascularization strategy in elderly patients with CS complicating AMI exist. We performed an analysis of age-related differences in outcome in 280 consecutive patients with AMI complicated by CS who underwent primary percutaneous coronary intervention (PCI) between January 1995 and September 2004 and who were included in a single-center prospective registry of primary PCI for AMI. Of the 280 patients with CS, 104 (37%) were > or = 75 years. The mean age of the elderly group was 81 +/- 5 years, and half of the patients were > or = 80 years. Most patients in both groups underwent PCI within 6 hours of their symptom onset. The PCI success rates were 92% in the elderly group and 97% in the younger patient group (P = .062). The 6-month mortality rates were 56% in the elderly group and 26% in the younger patient group (P < .001). At multivariate analysis, the variables independently related to the risk of 1-year mortality in the elderly group were age (hazard ratio 1.07, 95% CI 1.02-1.12, P = .005) and PCI failure (hazard ratio 4.01, 95% CI 1.53-10.51, P = .005). A strategy of routine emergency PCI in elderly patients with CS complicating AMI is highly feasible. Among elderly patients, age remains to be a strong predictor of mortality. However, outcome after successful PCI is better than previously reported.

Outcomes of Patients Consented But Not Randomized in a Trial of Primary Percutaneous Coronary Intervention in Acute Myocardial Infarction (The CADILLAC Registry)

Baseline features, management, and outcomes of patients who had acute myocardial infarction (AMI) and were excluded from randomized trials of primary percutaneous coronary intervention (PCI) have not been well described. We examined the baseline features and outcomes of patients who had AMI and were excluded due to angiographic ineligibility from a randomized trial of primary PCI. The CADILLAC trial evaluated 4 primary PCI strategies in patients who had AMI without cardiogenic shock. Of 2,681 patients who consented, 599 (22.3%) were subsequently excluded from randomization due to protocol-specified angiographic findings. These patients were enrolled in a formal in-hospital registry and were treated at the discretion of attending physicians. Registry versus randomized patients were older (median age 61.9 vs 59.0 years, p = 0.002), more frequently had 3-vessel disease (52.4% vs 15.6%, p = 0.0001), and more frequently had lower left ventricular ejection fraction (45% vs 50%, p = 0.002). Registry patients were treated with PCI (n = 234), coronary artery bypass grafting (n = 136), or medically only (n = 226). In-hospital mortality rate among all patients who consented was 2.2% and was higher among registry than among randomized patients (4.0% vs 1.6%, relative risk 2.45, p = 0.001). Within the registry, covariate-adjusted risk of mortality was lower among patients who were treated by PCI compared with those who were treated medically (odds ratio 0.21, p=0.03). In conclusion, angiographic ineligibility for randomization in a large, prospective, primary PCI trial was associated with numerous high-risk demographic characteristics and higher short-term mortality. Nonetheless, the overall survival of patients who were referred for primary PCI was excellent, and performance of primary PCI versus medical therapy was associated with increased survival among excluded patients.