ST peak during percutaneous coronary intervention serves as an early prognostic predictor in patients with ST-segment elevation myocardial

Major Adverse Cardiovascular Events: An Inevitable Outcome of ST-elevation myocardial infarction? A Literature Review

Major adverse cardiovascular events (MACE) remain the major cause of mortality and morbidity in patients with STEMI (ST-elevation myocardial infarction). The current literature is aimed to analyze the occurrence of MACE following STEMI irrespective of treatment provided, and follow up after the first diagnosis of STEMI. A PubMed search for Studies of STEMI identified 24,244 articles. After applying our inclusion/exclusion criteria, we found out 75 articles of relevance wherein MACE and its components were considered to be the primary endpoint. These 75 articles included eight Cohort Studies, 13 clinical trials including five randomized controlled trials (RCT), one case-control Study, one cross-sectional study, one review article, and 51 other observational studies. Our analysis shows that MACE remains one of the strongest adverse outcomes among STEMI patients. The current literature review found out the incidence of MACE was 4.2 % to 51% irrespective of the mode of treatment, and follow-ups lasting up to 10 years from the time of STEMI diagnosis.

Comparison of Outcome of Patients With ST-Segment Elevation Myocardial Infarction and Complete Versus Incomplete ST-Resolution Before Primary Percutaneous Coronary Intervention

Some patients presenting with ST-segment elevation myocardial infarction (STEMI) have complete ST resolution in the electrocardiogram, which may be clinical useful in the triage of patients with STEMI. However, the importance of complete ST resolution in these patients remains uncertain. Thus, the purpose was to describe the prognosis of patients with complete ST resolution before primary percutaneous coronary intervention (PCI). Continuous ST monitoring from arrival until 90 minutes after PCI was performed in 933 patients with STEMI. Complete ST resolution was defined as no residual significant ST elevations before intervention. The patients were followed clinically for 5.5 years (range 0 to 6.8 years). Infarct size and myocardial salvage were assessed in a subgroup of patients (n = 221) by cardiovascular magnetic resonance. Complete ST resolution was observed in 24% of the patients, who had a higher incidence of Thrombolysis In Myocardial Infarction grade 2/3 flow before intervention (64% vs 24%), smaller infarct size (6% vs 11%), and higher myocardial salvage index (0.82 vs 0.69; all p <0.001) compared with patients with continuous ST elevations. Complete ST resolution was associated with a significantly lower rate of the composite end point of all-cause death and admission for heart failure (14% vs 22%; p = 0.006) although it only tended to be an independent predictor in a multivariate analysis (hazard ratio 0.69, 95% CI 0.49 to 1.06; p = 0.09). In conclusion, compared to patients without incomplete ST resolution, patients with STEMI and complete ST resolution before primary PCI have a higher incidence of normalized epicardial flow before PCI, a larger myocardial salvage and smaller infarct size after the procedure and presumably improved long-term outcome compared with incomplete ST resolution.

Targeting reperfusion injury in the era of primary percutaneous coronary intervention: hope or hype?

Introduction of reperfusion therapy by primary percutaneous coronary intervention (PCI) has resulted in improved outcomes for patients presenting with ST-segment elevation myocardial infarction. Despite the obvious advantages of primary PCI, acute restoration of blood flow paradoxically also jeopardises the myocardium in the first minutes of reperfusion-a phenomenon known as reperfusion injury. Prevention of reperfusion injury may help to improve outcome following primary PCI. This review focuses on the clinical evidence of potential therapeutic cardioprotective methods as adjuvant to primary PCI. Despite overall disappointing, there exists some promising strategies, including ischaemic postconditioning, remote ischaemic conditioning, pharmacological conditioning with focus on adenosine, cyclosporine A, glucose-insulin-potassium, exenatide, atrial natriuretic peptide and metoprolol and cooling. But hitherto no large randomised study has demonstrated any effect on outcome, and ongoing studies that address this issue are underway. Moreover, this review will discuss important clinical predictors associated with reperfusion injury during primary PCI that may interfere with a potential protective effect (pre-PCI thrombolysis in myocardial infarction flow, preinfarction angina, collateral flow, duration of ischaemia and hyperglycaemia). This paper will also provide a short overview of the technical issues related to surrogate endpoints in phase II trials. Based upon these discussions, the paper will provide factors that should be taken into account when designing future clinical studies.