Acute Myocardial Events Research Articles

Coronary Computed Tomographic Angiography Imaging as a Prognostic Indicator for Coronary Artery Disease: Data from a Lebanese Tertiary Center.

Background:Coronary artery disease (CAD) is a major cause of death and disability worldwide. Coronary computed tomographic angiography (CCTA) is a noninvasive imaging technique with a high negative predictive value (NPV). Most studies were done in developed countries, where the prevalence of CAD does not reflect the actual disease burden in developing countries, such as Lebanon.Methods:We retrospectively evaluated the prognostic value of CCTA in predicting acute myocardial events (AMEs) in 200 Lebanese patients. We determined if specific medical and radiological characteristics are linked with AME and looked for any association between the patient's medical risk factors and the type/location of detected atheromatous plaques. Patients' records were reviewed, and the follow-up period of 5–8 years ensued. Chi-square/Fisher test and Student's t-test were used, in addition to multinomial logistic regression to adjust for the confounding variables. P <0.05 was considered statistically significant.Results:Our study showed that CCTA had a NPV that reaches 97.9% in asymptomatic patients, a positive predictive value (PPV) of 76.4% for symptomatic patients, a sensitivity of 88.9%, and a specificity of 52.5%. AMEs were significantly increased in patients with a mixed plaque type and/or a moderate-to-severe lumen reduction on CCTA.Conclusions:CCTA is a sensitive modality for plaque detection and is found to have a remarkably high NPV for asymptomatic patients. A CCTA, along with a low pretest clinical probability of CAD, can be sufficient to rule out an AME for up to 8 years.

The Use of Routine Troponins Following Endovascular Repair of Abdominal Aortic Aneurysms to Detect Perioperative Cardiovascular Events

Introduction: Incidence of perioperative cardiac complications following endovascular aneurysm repairs (EVAR) range from 2-10% (1). Approximately 60% of all perioperative deaths in EVAR surgery are from cardiac causes (2, 3, 4). Detecting myocardial infarctions in the post-operative period remains challenging as the majority of patients remain asymptomatic during an event (5). Methods: In a retrospective cohort study a total list of 105 patients over 18 months were identified in this hospital that had EVARs. 25 of these were excluded from the study as they failed to get an ECG or troponins performed postoperatively. Routine troponins and ECGs within 12 hours and again within 48 hours of the EVAR procedure in order to detect acute cardiovascular events. Results: 16% (n=13) of patients had a positive troponin detected routinely. Of these, 15% (n=2) were diagnosed with an acute myocardial event based on ECG findings, coronary angiogram and assessment by a cardiologist. Two further patients had acute myocardial events, however these were detected after routine troponins and ECGs were taken. Of our four patients with cardiac events, only one reported signs or symptoms consistent with a classical myocardial infarction. Discussion: Positive predictive value of routine troponins is 15% in detecting acute myocardial events. As a result, their routine use is not advised. ECGs could be performed routinely pre- and post-operatively and troponins taken if there are ECG changes in keeping with a myocardial event.

Evaluation of the Effectiveness of a Phone Based Care Coordination Pilot on Hospital Utilisation and Costs for Patients With Chest Pain

A small percentage of the population represents a disproportionate number of attendances at emergency departments (ED). "Frequent presenters" to ED with chest pain do not always fit into established pathways for acute myocardial events. With accelerated "rule out" protocols, patients are often discharged from the ED after short lengths of stay. This research will evaluate the effectiveness of a phone based care-coordination pilot designed to meet the needs of patients attending ED with cardiac and non-cardiac chest pain. A longitudinal, single-arm interventional study with retrospectively recruited control group. Ninety-five patients were enrolled as the intervention group; 97 patients were retrospectively identified as controls. These patients had re-presented with chest pain within 6 months of a cardiac event, or attended hospital within 12 months two or more times with chest pain and/or complex needs. Intervention group patients were holistically assessed then phone-coached to support self-management of chest pain over 6 months. Following descriptive and univariate analysis, multivariate analysis was conducted to adjust for noted differences between the intervention and control groups. Thirty-day representation to ED was significantly less for the intervention group (14.1%) compared to controls (27.7%). After adjusting for baseline differences, intervention patients were more than two-fold less likely to re-present compared to controls (OR=0.42, 95%CI: 0.19-0.96). After adjustment for baseline differences, the savings in subsequent inpatient costs was $1588 per person, as a result of intervention, patients were less likely to have inpatient readmissions (16.3%) compared to controls (20.2%), although this was not statistically significant (p=0.588). A phone based care-coordination pilot with targeted interventions has the potential to reduce ED presentations and hospital readmissions among patients representing with chest pain.

Is it more accurate to measure the absolute or the relative change of new high or ultrasensitive troponin assays to diagnose acute myocardial infarction?

In emergency department patients with symptoms suggestive of acute myocardial infarction, is the absolute or relative change of cardiac troponin assays (either high sensitivity or ultrasenstive) more accurate in diagnosing acute myocardial infarction at 1 to 2 hours postpresentation? Rechlin T, Ifran A, Twerenbold R, et al. Utility of absolute and relative changes in cardiac troponin concentrations in the early diagnosis of acute myocardial infarction. Circulation 2011;124:136-45. To evaluate the accuracy of new troponin assays in diagnosing acute myocardial events.

Direct cardiac injection of G-CSF mobilized bone-marrow stem-cells improves ventricular function in old myocardial infarction

Autologous transplant of bone marrow stem cells (BMSC), although extremely useful after acute myocardial events, has not been evaluated in patients with old (> one-year-old) myocardial infarction. Our aim was to determine if CD34 +-enriched peripheral-blood cells, obtained by apheresis, injected directly into the severely damaged myocardium of five patients with old myocardial infarction could restore depressed myocardial function. We found that 28 weeks after revascularization and peri-infarction injection of the enriched CD34 + peripheral mononuclear cells, ventricular hemodynamic parameters that included left ventricular ejection fraction, left ventricular diastolic volume, ventricular systolic volume and left ventricular diastolic diameter approximated normal values and there was no restenosis; two patients have been followed for > 52 weeks and their parameters are within normal values. In conclusion, intramyocardial injection of easily obtained CD34 + enriched peripheral blood cells represent an encouraging procedure for patients with severely scarred and dysfunctional myocardium.

C-reactive protein-induced in vitro vasorelaxation is an artefact caused by the presence of sodium azide in commercial preparations.

Although C-reactive protein (CRP) is increasingly recognized as an independent risk factor for acute myocardial events, recent evidence suggests that it can directly induce vasorelaxation. This study aimed to investigate the mechanism of this CRP-induced response. Isometric tension recordings were used to measure endothelium-dependent and endothelium-independent vascular smooth muscle relaxation in isolated rabbit aortic rings. CRP generated in-house by genetic engineering and expressed in Chinese hamster ovary cells, CRP purified from ascites, and CRP obtained from commercial sources were assessed for vasorelaxing properties. Only the commercial CRP preparation induced vasorelaxation; more than half maximal relaxation was observed at 0.025 microg/mL and maximum relaxation attained at 0.25 microg/mL. Commercial CRP contains high levels of sodium azide, a well-known vasorelaxant. Removal of this agent by dialysis abolished the vasodilatory effect of commercial CRP. Sodium azide alone at concentrations equivalent to that present in the commercial CRP produced a near-identical relaxation pattern to the undialyzed commercial product. CRP has no vasorelaxant properties per se, and the reported vasorelaxant ability of CRP is an artifact caused by sodium azide present in commercial preparations of this agent.

Clinical research for surgeons in palliative care: challenges and opportunities.

Symptom management and palliative medicine have gained growing interest among physicians and other health care providers. One reason might be the profound shift in patient demographics and associated diseases. What was once a formidable condition, such as an acute coronary occlusion, for the most part follows a straightforward clinical protocol today with interventional cardiology and cardiac procedures. Sudden death from acute myocardial events among people in their sixth or seventh decade has become relatively uncommon. Instead, the elderly population is chronically plagued by heart failure, a condition present in nearly every other person more than 85 years of age. In the younger population of 65 to 74 years of age, advanced cancer has surpassed heart disease as the most frequently cited cause of death. We live in a rapidly aging society; 78% of people in the United States will live past their 65th birthday. Congestive heart failure, advanced cancer, stroke, and dementia—the four formidable chronic morbidities—all share one common characteristic. There is no cure for their underlying disease process. Most current treatment modalities aim for disease control and symptom palliation rather than cure in the strict sense. Surgeons might wonder how palliative care fits into their surgical practice. This might be because of the surgical myth that the principal role of the surgeon is to cure the patient and the business of palliation is deemed best relegated to the nonsurgeons. But the presumed delineation between cure and palliation is becoming increasingly blurred because of the underlying patient demographics and associated disease processes that are fundamentally incurable, at least from today’s vantage point. In the end, it might be more constructive to consider the role of palliative care in surgery in terms of specific patient-oriented clinical outcomes, rather than in terms of the elusive cure versus palliation. In addition to survival, examples of patient-oriented clinical outcomes include functional status; relief from symptoms such as pain, dyspnea, and cachexia; and emotional and psychological well-being—all of which contribute to quality of life. In the aforementioned context, there is a need to define what palliative surgery is, and what a palliative surgeon is. Palliative surgery is not to be construed as a type of surgery exclusive of any intent to cure. When cure is possible, palliative surgery is inclusive of curative intervention. In addition, palliative surgery does not connote any degree of diminishment or retrenchment of care. If anything, palliative surgery might provide more aggressive care, recognizing the value of medical, procedural, or other interventions leading to symptom relief and enhanced quality of life. Symptom palliation might even result in increased patient survival, whether or not cure is possible in the traditional sense. What distinguishes palliative surgery is the palliative surgeon’s expansion of clinical outcomes beyond surgical morbidity or mortality outcomes and recurrence of disease to include outcomes that are meaningful to the patient. Palliative surgeons acknowledge that death can be a natural and expected outcome of an advanced disease process, such as cancer and systemic atherosclerotic disease. They aim to set appropriate goals of care and to offer other clinical services for the total care of the patient and family. For most patients with advancing atherosclerotic disease, malignancy, and dementia, relief from debilitating symptoms and quality of life might be just as or more important than the number of years lived. A concenNo competing interests declared.