Acute ST-elevation myocardial infarction

Acute ST-elevation myocardial infarction (STEMI) remains the leading cause of death in industrialized countries. For many patients, a myocardial infarction is the first presentation of atherosclerotic coronary artery disease. This often results in delays in obtaining medical attention and subsequently poorer outcome, certainly because symptoms are often misinterpreted. Furthermore, a large proportion of STEMI patients die from lethal arrhythmias even before reaching medical facilities. Numerous studies during the past decades have firmly established the paradigm of achieving early, complete and sustained infarct-related artery patency. Because of a more aggressive therapy and rapid revascularization using either fibrinolysis or primary PCI, many patients do remarkably well after STEMI. Unfortunately, adherence to treatment guidelines is often suboptimal, leading to less favourable outcome. Also, more efficient care for patients with myocardial infarction has led to a rapidly growing population of patients with chronic heart failure.     

ST-elevation myocardial infarction in octogerians

Coronary artery disease is the leading cause of death in developed countries and its incidence and severity is greater among older patients. So, because of the ageing of the population, clinicians will be increasingly confronted in daily practice with managing acute coronary syndrome in extreme old age and high-risk patients. Despite this demographic reality, several large randomized controlled trials evaluating the benefit-risk ratio of invasive versus conservative approach have systematically excluded elderly patients. The extrapolation of evidence-based medicine, initially focused on younger patients, is often contentious in this population and because of the lack of clear and specific recommendations in the elderly, the optimal management of STEMI in octogenarians remains a topic of debate. Elderly patients present unique issues related to the ageing process and multiple comorbid diseases making difficult the extrapolation of evidence obtained on younger demographics. Data from registries seem to support, nevertheless, the benefit of primary revascularization by PCI of the culprit lesion in "selected" octogenarians with a high technical success rate, few complications, acceptable short and long-term mortality rate and quality of life. Obviously, the "ideal octogenarian" doesn't exist and all the old patients are not suitable for an invasive approach. Managing elderly patients requires not only cardiological skills but also geriatric acknowledges and the individualized geriatric assessment is the corner store of the decision process. The aim is to screen for the presence of comorbidities (cognitive disorders, functional decline, anemia, renal insufficiency…), social isolation and existence of an underlying frailty. To conclude, the optimal strategy for the management of STEMI in octogenarians is not univocal: the best approach is the one that offers the greater benefits regard considerations of general health.     

Acute ST-elevation myocardial infarction secondary to paradoxical embolism

Acute ST-elevation myocardial infarction (STEMI) is a life threatening condition usually caused by rupture of an atheromatous plaque in the coronary arteries. Other causes, such as septic emboli, cholesterol emboli and cocaine abuse have been reported. We report a case of acute STEMI in a young female without any vascular risk factors due to a presumptive paradoxical embolism via a secundum atrial septal defect (ASD). Young patients without vascular risk factors presenting with acute myocardial infarction should be investigated to exclude an underlying cause of their myocardial infarction, such as a paradoxical embolus.     

A LEOPARD mimicking ST-elevation myocardial infarction

A 47-year-old man was referred because of an acute anterolateral ST-segment elevation myocardial infarction. Coronary angiography showed marked ectasia of the coronary arteries, with no obstructive lesions. Ventriculography strongly suggested severe left ventricular hypertrophy, later confirmed by cardiovascular magnetic resonance imaging. Complete clinical investigation showed that the patient also had multiple lentigines, ocular hypertelorism, and deafness. These associations led to the diagnosis of LEOPARD (Lentigines, Electrocardiographic anomalies, Ocular hypertelorism, Pulmonary stenosis, Anomalies of the genitalia, Retarded growth, and Deafness [sensorineural]) syndrome. Although uncommon, LEOPARD syndrome is important to recognize because it can be associated with serious adverse cardiac events, particularly in patients with severe left ventricular hypertrophy.     

Electrocardiographic diagnosis of ST-elevation myocardial infarction

The ECG is an essential part of the initial evaluation of patients who have chest pain, especially in the immediate decision-making process in patients who have ST-elevation myocardial infarction. This article reviews and summarizes the current information that can be obtained from the admission ECG in patients who have ST-elevation acute myocardial infarction, with an emphasis on: (1) prediction of final infarct size, (2) estimation of prognosis, and (3) the correlations between various ECG patterns and the localization of the infarct and the underlying coronary anatomy.     

Reperfusion strategies for ST-elevation myocardial infarction

Management of ST-elevation myocardial infarction requires rapid, sustained and early restoration of flow in the infarct-related artery to minimize myocardial damage and to improve clinical outcomes. Primary percutaneous coronary intervention (PCI) is the preferred therapy but is limited by restricted availability and delays in implementation. Fibrinolytic administration is widely available but is limited by its failure to achieve Thrombolysis in Myocardial Infarction grade 3 flow in many patients, re-infarction, and intracranial hemorrhage. A combination approach to reperfusion--facilitated PCI--involves the administration of a pharmacologic agent to improve reperfusion with PCI. The evidence supporting facilitated PCI varies according to the pharmacologic regimen at this time.     

HLA-DRB1*01 associated with cutaneous hypersensitivity induced by nevirapine and efavirenz

HLA typing, demographic and immunological risk factors for nevirapine and efavirenz reactions were studied in a French cohort of HIV patients. Cases with isolated rash were significantly associated with HLA-DRB101 allele. No liver toxicity was observed and no association was detected with the percentage of CD4 T-cells. This study suggests that HLA-DRB101 allele plays an important role in susceptibility to cutaneous reactions associated with nevirapine and efavirenz in HIV patients.     

Lower Frequency of HLA-DRB1*01 in Southwestern Iranian Patients with Atherosclerosis

Background: Human leukocyte antigen (HLA) complex is a gene family involved in antigen presentation associated with protection or susceptibility to inflammatory, infectious and autoimmune diseases. Atherosclerosis is a chronic inflammatory disease in which HLA molecules play a role in the initiation and development of the disease through presentation of self or foreign antigens to T cells. Objective: To investigate the association of HLA-DRB1 alleles with atherosclerosis in a sample of southwestern Iranians. Methods: We performed an analytical cross-sectional study involving 96 patients with atherosclerosis and 72 controls. HLA-DRB1 genotyping was performed by PCR-SSP method. Results: We observed a significantly lower frequency of DRB1*01 in patients with coronary artery atherosclerosis than in controls (4.68% vs. 13.1, P=0.0052, OR=3.09, CI 95%: 1.35-7.05). However, this allele showed a positive association with high blood pressure (P=0.009) in patients. Furthermore, DRB1*16 allele was associated with hyperlipidemia (P=0.008) in patients. Conclusion: Our results demonstrated that DRB1*01 may be a protective allele against atherosclerosis in individuals who live in southwest of Iran. The mechanism of this protection needs further investigation.     

Polycythaemia vera presenting as ST-elevation myocardial infarction

A case of ST-elevation myocardial infarction as the first presentation of polycythaemia vera is described. The discussion summarises the evidence for the safety and efficacy of contemporary ST-elevation treatment strategies in the setting of polycythaemia vera.     

Reperfusion treatment of ST-elevation acute myocardial infarction

Reperfusion treatment of ST-segment elevation myocardial infarction (STEMI) is one of the medical interventions with the largest potential for saving human lives, independently of age and gender. An attempt to reopen an acutely occluded coronary artery can be done within a wide array of possibilities, from the simple administration of aspirin to the combination of drugs and complex coronary artery interventions. Fibrinolytic drugs and aspirin represent the easiest way to attempt reperfusion and together offer an acceptable compromise between opportunity for treatment and efficacy. Other drugs and the use of invasive revascularization alternatives yield further advantages, and in some high-risk subgroups may be the most rational treatment approach. Beyond investigator's bias and dedication to either form of reperfusion treatment, interventions and/or drugs should be used as needed (and as possible) to increase the overall impact of reperfusion treatment in the community, taking advantage of the best potential of each approach. Most resources have been directed toward the improvement of reperfusion rates with the combination of fibrinolytic and antiplatelet drugs or with angioplasty. These efforts have certainly raised costs, but have not decisively improved clinical outcome nor have they broadened the impact of reperfusion treatment in the community. Indeed, the main shortcoming of reperfusion therapy is that the cohort of untreated patients is still larger than the cohort of treated patients. At a time when mortality of patients with STEMI reaching the hospital and receiving treatment has decreased significantly, the prehospital diagnosis and treatment of STEMI with the objective of enlarging the treated population and shortening the pretreatment delays is likely the best strategy to further reduce mortality. The need for a population approach to treatment of STEMI is even more obvious when considering the expanding patient load that continuously worsens its clinical risk profile, together with the increasing incidence of diabetes, obesity, hypertension, and smoking habits. The target for improving reperfusion treatment of STEMI in the future, and thereby saving more lives, seems now to involve a cultural change and fulfillment of an organizational mission more than an incremental improvement in the current pharmacologic or interventional approach. These epidemiologic and social aspects of contemporary medicine deserve full attention at a time when researchers, clinicians, and health care providers tend to focus primarily on technological advances.     

Bimodal response to aspirin loading in acute ST-elevation myocardial infarction

Patients with stable coronary disease who exhibit platelet hypo-responsiveness to aspirin (ASA) have worse outcomes. Little data exist regarding platelet response to ASA in ST-elevation myocardial infarction (STEMI) patients. Our objective was to assess acute platelet response to ASA loading in STEMI patients undergoing primary percutaneous coronary intervention (PCI). The study comprised 102 consecutive patients with STEMI. All patients received a loading dose of 300?mg chewable ASA upon admission. Platelet reactivity was assessed immediately prior to primary PCI, at a median of 95(63?139) minutes after ASA loading. A bimodal response to arachidonic acid (AA) stimulation was observed, such that two distinct populations could be discerned: “good responders” had a mean AA-induced platelet aggregation of 36?±?11% vs. 79?±?9% for “poor responders.” Despite equivalent demographic, clinical, and angiographic characteristics, good responders were significantly more likely to demonstrate early ST-segment resolution ≥70% after primary PCI (80% vs. 48%, p?=?0.001), suggestive of better myocardial reperfusion. Early inhibition of AA-induced platelet aggregation post-ASA loading in the setting of STEMI is associated with better tissue reperfusion; however, a sizeable proportion of patients do not achieve significant inhibition of AA-induced platelet aggregation in response to ASA loading at the time of primary PCI.     

The conundrum of HLA-DRB1*14:01/*14:54 and HLA-DRB3*02:01/*02:02 mismatches in unrelated hematopoietic SCT

Uncertainty still exists on the role of polymorphisms outside the HLA-DRB1 binding site or inside the HLA-DRB3 binding groove in unrelated hematopoietic SCT (HSCT). The ideal model to solve the conundrum consists of the transplants mismatched for HLA-DRB1*14:01/*14:54 and/or for HLA-DRB3*02:01/*02:02. A task force was set up in Italy to recruit transplanted pairs defined as HLA-DRB1*14:01 before 2006, the year crucial for the proper definition of the HLA-DRB1*14:54 allele in molecular biology. Out of 2723 unrelated pairs, 189 transplanted in Italy from 1995 to 2006 were HLA-DRB1*14:01 positive; 103/189 pairs with good historical DNA were retyped for HLA-DRB1*14 and HLA-DRB3 at-high resolution level; 31/103 pairs had HLA-DRB1*14 and/or HLA-DRB3 mismatched; 99/103, having complete clinical data, underwent statistical analysis for OS, TRM, disease-free survival and acute and chronic GvHD. No significant involvement of HLA-DRB1*14:01/*14:54 or HLA-DRB3*02:01/*02:02 mismatches was found, either alone or combined. Our findings suggest that disparities at exon 3 of the HLA-DRB1 gene seem unlikely to influence the outcome after HSCT. The same may be envisaged for HLA-DRB3(*)02:01 and (*)02:02 alleles which, although differing in the Ag binding site, seem unable to modulate an appreciable immune response in an HSCT setting.     

Differentiating ST-elevation myocardial infarction from nonischemic ST-elevation in patients with chest pain

Current guidelines state that patients with compatible symptoms and ST-segment elevation (STE) in ≥2 contiguous electrocardiographic leads should undergo immediate reperfusion therapy. Aggressive attempts at decreasing door-to-balloon times have led to more frequent activation of primary percutaneous coronary intervention (pPCI) protocols. However, it remains crucial to correctly differentiate STE myocardial infarction (STEMI) from nonischemic STE (NISTE). We assessed the ability of experienced interventional cardiologists in determining whether STE represents acute STEMI or NISTE. Seven readers studied electrocardiograms of consecutive patients showing STE. Patients with left bundle branch block or ventricular rhythms were excluded. Readers decided if, based on electrocardiographic results, they would have activated the pPCI protocol. If NISTE was chosen, readers selected from 12 possible explanations as to why STE was present. Of 84 patients, 40 (48%) had adjudicated STEMI. The percentage for which readers recommended pPCI varied (33% to 75%). Readers' sensitivity and specificity ranged from 55% to 83% (average 71%) and 32% to 86% (average 63%), respectively. Positive and negative predictive values ranged from 52% to 79% (average 66%) and 67% to 79% (average 71%), respectively. Broad inconsistencies existed among readers as to the chosen reasons for NISTE classification. In conclusion, we found wide variations in experienced interventional cardiologists in differentiating STEMI with a need for pPCI from NISTE.