Episode Of Acute Myocardial Infarction Research Articles

Association between tamoxifen use and acute myocardial infarction in women with breast cancer.

The relationship between tamoxifen use and acute myocardial infarction in women with breast cancer remains uncertain. The goal of the study was to assess whether tamoxifen use could be associated with acute myocardial infarction in women with breast cancer in Taiwan.A population-based case–control study was conducted to analyze the database of the Taiwan National Health Insurance Program. Totally, 489 women with breast cancer aged 20 to 84 years having the first episode of acute myocardial infarction from 2000 to 2011 were found as the cases. In addition, 1718 women with breast cancer aged 20 to 84 years without any type of ischemic heart disease were selected as the matched controls. Ever use of tamoxifen was classified as the studied women who had at least a prescription for tamoxifen before the index date. Never use of tamoxifen was classified as the studied women who never had a prescription for tamoxifen before the index date. We used the multivariable logistic regression model to estimate the odds ratio (OR) and 95% confidence interval (CI) for acute myocardial infarction associated with tamoxifen use.In a multivariable-adjusted analysis, women with acute myocardial infarction were 1.71 times more likely to be exposed to tamoxifen than those women without acute myocardial infarction (adjusted OR 1.71, 95% CI 1.38–2.13).The odds of tamoxifen use are 1.71 times higher in women with acute myocardial infarction versus those women without acute myocardial infarction in Taiwan.

Decade Long Trends (2001–2011) in the Incidence Rates of Initial Acute Myocardial Infarction

Despite the magnitude and impact of acute coronary disease, there are limited population-based data in the United States describing relatively recent trends in the incidence rates of acute myocardial infarction (AMI). The objectives of this study were to describe decade long (2001-2011) trends in the incidence rates of initial hospitalized episodes of AMI, with further stratification of these rates by age, sex, and type of AMI, in residents of central Massachusetts hospitalized at 11 area medical centers. The study population consisted of 3,737 adults hospitalized with a first AMI at 11 medical centers in central Massachusetts on a biennial basis between 2001 and 2011. The median age of this study population was 70 years, 57% were men, and 90% were white. Patients hospitalized during the most recent study years (2009/11) were younger, more likely to be men, have more co-morbidities, and less in-hospital complications as compared with those in the earliest study years (2001/03). The overall age-adjusted hospital incidence rates (per 100,000 persons) of initial AMI declined (from 319 to 163), for men (from 422 to 219), women (from 232 to 120), for patients with a ST segment elevation (129 to 56), and for those with an non-ST segment elevation (190 to 107) between 2001 and 2011, respectively. In conclusion, the incidence rates of initial AMI declined appreciably in residents of central Massachusetts who were hospitalized with AMI during the years under study.

Factors Associated with Inadequate Management of Antiplatelet Agents in Perioperative Period of Non-Cardiac Surgeries.

BackgroundThe current guidelines dispose recommendations to manage antiplatelet agents in the perioperative period; however, the daily medical practices lack standardization.ObjectivesTo asses factors associated with inadequate management of antiplatelet agents in the perioperative period of non-cardiac surgeries.MethodsCross-sectional Study conducted in hospital from October 2014 to October 2016. The study dependent variable was a therapy that did not comply with the recommendations in the Brazilian Association of Cardiology (SBC) guidelines. The independent variables included some characteristics, the people in charge of the management and causes of lack of adherence to those guidelines. Variables were included in the multivariate model. Analysis was based on the odds ratio (OR) value and its respective 95% confidence interval (CI) estimated by means of logistic regression with 5% significance level.ResultsThe sample was composed of adult patients submitted to non-cardiac surgeries and who would use acetylsalicylic acid (aspirin) or clopidogrel (n = 161). The management failed to comply with the recommendations in the guidelines in 80.75% of the sample. Surgeons had the highest number of noncomplying orientations (n = 63). After multivariate analysis it was observed that patients with a higher level of schooling (OR = 0.24; CI95% 0.07-0.78) and those with a previous episode of acute myocardial infarction (AMI) (OR = 0.18; CI95% 0.04-0.95) had a higher probability of using a therapy complying with the guidelines.ConclusionPositive association between patients’ schooling level, or those with a history of previous AMI, with management of the use of aspirin and clopidogrel in the perioperative period of non-cardiac surgeries. However, diverging conducts stress the need of having internal protocol defined.

Prognostic impact of unrecognized myocardial scar in the non-culprit territories by cardiac magnetic resonance imaging in patients with acute myocardial infarction.

Unrecognized myocardial scar by late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) is strongly associated with cardiac event in patients with stable coronary artery disease. The purpose of this study was to evaluate the prognostic impact of unrecognized non-infarct-related LGE (non-IR-LGE) in patients with acute myocardial infarction (AMI). We studied 269 patients with a first clinical episode of AMI underwent cardiac MRI within 6 weeks after onset (209 men; age, 66 ± 12 years). LGE, cine MRI and T2-weighted imaging were obtained to evaluate the presence and extent of LGE and to evaluate cardiac function. Major adverse cardiac events (MACE) were defined as cardiovascular death, non-fatal AMI, unstable angina requiring revascularization, fatal arrhythmia, and heart failure. Unrecognized non-IR LGE was observed in 13.0% of patients. During follow-up periods (median, 22 months; range, 3-95 months), 8.9% of patients experienced MACE in this study. In addition, 22.9% of patients with unrecognized non-IR LGE and 6.8% of patients without unrecognized non-IR-LGE experienced MACE (P < 0.01). The presence of unrecognized non-IR LGE predicted MACE with a hazard ratio of 3.45 (95% confidential interval, 1.03-11.47; P < 0.01). In addition, unrecognized non-IR LGE was the strongest independent predictors of MACE with a hazard ratio of 3.30 by the Cox proportional hazards model (P < 0.01). In contrast, angiography-proven multi-vessel disease and transmural extent of infarct-related LGE were not independently associated with MACE. Among patients with a first clinical episode of AMI, unrecognized non-IR myocardial scar provides incremental prognostic value for predicting MACE beyond that of common clinical, angiographic and functional variables.

Abstract 058: Early Effect of Medicare Accountable Care Organizations on Acute Myocardial Infarction Episode Payments

Objective: Spending for acute myocardial infarction (AMI) episodes varies widely across hospitals, driven primarily by payments made more than 30 days after discharge. Through collective incentives and an emphasis on care coordination, Medicare accountable care organizations (ACOs) may help reduce this variation. To test this hypothesis, we analyzed national Medicare data. Methods: Using a 20% random sample, we identified Medicare beneficiaries admitted for AMI from January 2010 to December 2013. We distinguished admissions to hospitals affiliated with a Medicare ACO from those that were not. We then calculated 90-day, price-standardized, risk-adjusted episode payments made on behalf of beneficiaries, differentiating between early (index admission to 30 days post-discharge) and late payments (31 to 90 days). We also calculated component payments, including those for the index hospitalization, readmissions, physician services, and post-acute care. Finally, we used difference-in-differences estimation to measure the effect of admission to an ACO-affiliated hospital on early and late episode payments. Results: Over the study period, 15,219 beneficiaries were admitted to 299 eventual ACO-affiliated hospitals and 73,910 were admitted to 1,685 never ACO-affiliated hospitals ( p &lt;0.001). While beneficiaries admitted to eventual ACO-affiliated hospitals tended to be younger than those admitted to never ACO-affiliated hospitals (mean age: 79.2 ± 8.6 versus 80.0 ± 8.5, respectively; p =.003), they had similar levels of comorbidity (mean Elixhauser score: 2.7 ± 1.4 versus 2.7 ± 1.4, respectively; p =0.526). Mean 90-day episode payments were greater for ACO-affiliated hospitals [$24,887 versus $23,966; p &lt;0.001]. In the period after ACO implementation (2012 and 2013), total payments for AMI episodes fell by $1259 (Figure; p &lt;0.001). Most of this savings was attributable to decreases in early ($1118) versus late ($141) episode payments. However, none of these savings differed based on admission to an ACO-affiliated hospital ( p =0.363 for the difference). Conclusions: Early Medicare ACOs have not affected 90-day episode payments for AMI admissions. Future studies should explore the possibility of heterogeneity in effect based on ACO structure.

Effect of goal attainment theory based education program on cardiovascular risks, behavioral modification, and quality of life among patients with first episode of acute myocardial infarction: Randomized study

Effect of goal-attainment-theory-based education program on cardiovascular risks, behavioral modification, and quality of life among patients with first episode of acute myocardial infarction: randomized study BackgroundThe behavioral modification strategies should be explored at the time of admission to lead the maximum effect of cardiovascular risk management. AimsThis randomized study aimed to elucidate the effects of a nurse-led theory-based education program in individuals with a first episode of acute myocardial infarction on cardiovascular risks, health behaviors, and quality of life over 6 months. MethodsThe study involved a convenience sample of 64 patients with acute myocardial infarction who were randomly assigned to either the education group or the control group. The goal-attainment-based education program was designed to set the mutually agreed goals of risk management and the behavioral modification strategies for achieving those goals. Those in the control group received routine management only. The participants in both groups were contacted at 6–8 weeks and at 6 months after discharge to measure outcome variables. Repeated measure ANOVA was conducted using SPSSWIN (version 20.0) to determine the significance of differences in outcome variables over 6 months between the groups. ResultsBoth groups showed significant positive changes in cardiovascular risks, health behaviors, and quality of life over 6 months. The 2-year risk of cardiovascular disease was significantly reduced in both study groups, but with no significant interaction effect (F=2.01, p=0.142). The performance and maintenance of health behaviors (F=3.75, p=0.029) and the mental component of quality of life (F=4.03, p=0.020) were significantly better in the education group than the control group. ConclusionApplying a goal-oriented education program at an early stage of hospital management improved and maintained blood glucose, health behaviors, and mental component of the quality of life up to six months in individuals with a first episode of myocardial infarction. Further studies are warranted to explore the role of behavioral modification mediating between cardiovascular risk management and quality of life in this population.

Factors associated with anxiety and depression in hospitalized patients with first episode of acute myocardial infarction.

IntroductionEvaluation of anxiety and depression in cardiac patients is an area of nursing practice that is frequently neglected. The aim of the study was to explore anxiety and depression in hospitalized patients with their first episode of acute myocardial infarction.Material and methodsThe study sample included 148 hospitalized patients who had a first episode of acute myocardial infarction. Data collection was performed by the interview method using a specially designed questionnaire which included socio-demographic, clinical and other patients’ characteristics as well as the Hospital Anxiety and Depression Scale (HADS) to assess patients’ levels of anxiety and depression.ResultsAnalysis of data showed that 52% and 38% of participants had high levels of anxiety and depression, respectively. Furthermore, anxiety levels revealed a statistically significant association with anxiolytics (p = 0.005) and antidepressant medication (p = 0.026) in hospital, the belief that they will face difficulties in relations with the social and family environment (p = 0.009 and p = 0.002, respectively) and whether they considered themselves anxious (p = 0.003). Depression was statistically significantly associated with education level (p = 0.001), profession (p = 0.007), antidepressant medication in hospital (p ≤ 0.001), patients’ relations with nursing staff (p = 0.019) and patients’ belief that they will face difficulties in relations with the social and family environment (p ≤ 0.001 and p ≤ 0.001, respectively).ConclusionsThe results showed that socio-demographic and clinical characteristics should be taken into serious consideration when exploring anxiety and depression in patients with a first episode of acute myocardial infarction in order to implement appropriate interventions.

When the Innocent Bystander Becomes the Culprit: Two Episodes of STElevation Myocardial Infarction with Different Culprit Coronary Arteries in A Single Patient Occurring Two Days a Part

Background: Recurrent ST elevation myocardial infarction (STEMI) with different culprit lesions in a single patient occurring few days apart is uncommon with limited similar cases reported. Case Presentation: This is a case of a 53-year-old male who presented to the Emergency Department with left upper quadrant abdominal pain and an initial electrocardiogram showing ST elevation MI in the anterolateral leads. He underwent successful primary angioplasty of the culprit lesion (LAD) with placement of a single Everolimus drug-eluting stent with plans for staged intervention within a month of the remaining severe lesion in the left circumflex (LCx) artery (non-infarct related vessel). Two days after the initial STEMI, the patient experienced recurrence of abdominal pain with hypotension, and a repeat ECG revealed new ST segment elevation in the inferior leads. A repeat coronary angiogram demonstrated a widely patent stent in the LAD and the previously noted diseased LCx. No other new lesions were noted and the RCA was also patent. The patient then underwent a successful second primary PCI of the previously untreated severe lesion in the LCx. Conclusion: Consecutive episodes of acute myocardial infarction in different coronary arteries occurring within hours to a few days after primary PCI for STEMI is uncommon and can be catastrophic if not detected early. The mechanism and predisposing factors to such event are still unclear. The optimum interventional treatment strategy regarding the immediate management of STEMI in patients with multi-vessel disease remains controversial.

Heart Failure Predictors in a Group of Patients with Myocardial Infarction.

AIM:The present study considers of the prevalence of heart failure (HF) in patients suffering from acute myocardial infarction (AMI) in the University Hospital Centre of Tirana (UHCT) “Mother Theresa”; the demographic and clinical characteristics of the sample during hospitalization; and the main predictors of heart failure occurrence inside the group of patients suffering an AMI.MATERIAL AND METHODS:During a period of study from 2013-2015 we studied demographic and clinical data from 587 consecutive patients presenting with AMI; Framingham criteria were adopted for classifying patients with HF upon admission.RESULTS:A Killip class ≥ 2 was the main diagnostic criterion of HF during hospitalisation. HF was identified in 156 patients (26.6%). The subgroup with HF had significant differences when compared with the other patients with regard to age, sex (male), heart rate upon admission, systolic blood pressure on admission, previous episodes of AMI, glycemia on admission, previous antihypertensive treatment, previous revascularization procedures, peripheral vascular disease, chronic renal disease, ejection fraction (EF), anemia, and atrial fibrillation presence. Independent predictors for HF occurrence in the logistic regression model were EF, previous revascularization, peripheral vascular disease, age, sex, previous AMI, systolic blood pressure upon admission, and anaemia.CONCLUSION:As a conclusion, HF seems to be a common occurrence after AMI, in spite of changes in the epidemiological profile of the acute coronary syndrome. An increase in the incidence is registered as well, parallel to a decrease in the mortality following AMI. Attention must be shown for highly risked subpopulations, aged persons, patients with the previous coronary disease, and concomitant conditions.

The fundamental importance of smoking cessation in those with premature ST-segment elevation acute myocardial infarction.

Smoking is the most prevalent risk factor among young patients suffering acute myocardial infarction (AMI). In this review, we will present data on the detrimental consequences of continued smoking with regard to the recurrence of coronary events after an AMI at an early age. A prospective study with long-term follow-up of young survivors of AMI showed that continuation of smoking after a first episode of AMI was the strongest independent predictor of further cardiac events. In particular, persistent smokers had ∼2.5 times higher risk of a new coronary event when compared with nonsmokers. This emphasizes the fundamental importance of initiating smoking cessation treatment in all smokers with AMI during hospitalization. Extrapolating the results of previous studies showing the benefits of smoking cessation in middle-aged or elderly coronary patients, an even greater benefit should be expected in young patients because of their specific characteristics, which are presented in the current review. Young persistent smokers after a premature AMI constitute a high-risk subgroup for a recurrence of cardiac events. Therefore, smoking cessation is a key issue for improving their prognosis and all smokers should be offered effective antismoking treatment at the time of initial hospitalization.

HEMICHOREA ASSOCIATED WITH NON-KETOTIC HYPERGLICEMIA: REPORT OF TWO CASES AND BRIEF REVIEW OF THE LITERATURE

Introduction: Chorea is characterized as a hyperkinetic movement disorder that is caused by lesions on the basal ganglia. Many etiological factors have been described, including ischemia, infection, neoplasm and neurodegenerative disorders, such as Hun-tington’s disease. Non-ketotic hyperglycemia induced chorea is a rare, but reversible, condition usually associated with contralat-eral striatal radiological abnormalities. Case Report: Case 1: A 64 year-old Brazilian woman was admitted concerning about a 4-day history of involuntary, erratic and continuous movements with sudden onset affecting the left arm, leg and, partially, the left hemiface. Her past medical history was remarkable for arterial hypertension and type 2 diabetes mellitus. Neurologic examina-tion revealed the presence of choreic movements of the left hemiface, arm and leg. Case 2: A 63 year-old Brazilian woman was admitted concerning about an 1-day history of involuntary, without purpose, assymmetric, irregular and abrupt movements of the upper limbs and face associated with difficulty of speaking and swallowing. Her past medical history was remarkable for arterial hypertension and coronariopathy with two episodes of acute myocardial infarction four months before. There was no history of diabetes mellitus. On neurological examination, she presented severe dysartry and difficulty of swallowing associated with choreic movements of the upper limbs and face. Conclusion: In the present study, we describe two cases of chorea as a complication of non-ketotic hyperglycemia. A high index of clinical awareness and early suspicion of this possible association are extremely important, once the correct management and normalization of glycemia may result in complete recovery of neurologic symptoms.

Geographic and socioeconomic differences in access to revascularization following acute myocardial infarction.

Geographic and socioeconomic barriers may hinder fair access to healthcare. This study assesses geographic and socioeconomic disparities in access to reperfusion procedures in acute myocardial infarction (AMI) patients residing in Piedmont (Italy). Coronary Care Units (CCUs) were geocoded with a geographic information system (GIS) and the shortest drive time from CCUs to patients' residence was computed and categorized as 0 to <20, 20 to <40 and ≥40 min. Using data on AMI emergency hospitalizations in 2004-2012, we employed a log-binomial regression model to evaluate the relation between drive time and use of Percutaneous Transluminal Coronary Angioplasty (PTCA) occurring within 2 days after a hospitalization for an episode of AMI, and whether this relation varied depending on the period of hospitalization. A total of 29% of all cases with a diagnosis of AMI (n = 66 097), were revascularized within 2 days from the index admission. The further AMI patients lived from CCUs, the less likely they were to receive revascularization: compared with distance <20 min, RRs were respectively 0.84 [95% CI 0.80-0.88] and 0.78 [95% CI 0.71-0.86]. Findings also showed that less educated people had a lower relative risk of being revascularized compared to more educated people (RR = 0.78; 95% CI = 0.74-0.82). Both inequalities have reduced in recent years. This study provides evidence of reduced geographical and socioeconomic differences in revascularization use over time. Geography and socioeconomic status should not determine the type of treatment received for life-threatening conditions such as AMI.

Difficulties of Portuguese Patients Following Acute Myocardial Infarction: Predictors of Readmissions and Unchanged Lifestyles

Myocardial infarction can occur due to known risk factors and lifestyle choices. The difficulties that patients experience after discharge can lead to readmission and nonadherence to lifestyle change. The purpose of this study was to analyze the difficulties experienced by patients after hospitalization due to myocardial infarction and to identify the predictors of readmission and unchanged lifestyles. The study used a mixed-methods design across 106 patients who had experienced a first episode of acute myocardial infarction. The data were collected from two patient interviews and the patients' medical records. A logistic regression was used to predict unchanged lifestyle and readmission. In the first interview, 74.5% of the patients reported receiving information prior to discharge. Six months after discharge, 80.2% mentioned that they had changed their lifestyles, but only 59.4% reported that their health had improved, and 75.5% continued to have concerns regarding their health. Patients described difficulties with regard to psychological problems, family dynamics, professional issues, problems with managing cardiovascular symptoms, and complications associated with hospital interventions. A follow-up assessment revealed that 12.3% of patients had been readmitted for cardiovascular disease. The analysis revealed significant predictors of readmission amongst patients with hypertension and three-vessel disease. Specifically, the number of people in the household, per capita income, and a lack of information/education provided at discharge as well as problems related to mental health after discharge predicted unchanged lifestyle. An educational program might be advantageous to clarify doubts and involve patients in their own disease management.

MYOCARDIAL INFARCTION RELATED HOSPITALIZATIONS AND IN-HOSPITAL MORTALITY AMONG MALE AND FEMALE CALIFORNIA RESIDENTS, 2000-2013

We examined the first episode of acute myocardial infarction (AMI) related hospitalizations and in-hospital mortality trends by sex and age in California from 2000 to 2013. This retrospective analysis is based on data compiled by the California Office of Statewide Health and Planning Development

Risk factors and therapeutic coverage at 6 years in patients with previous myocardial infarction: the CASTUO study

ObjectivesTo determine the degree of risk factor control, the clinical symptoms and the therapeutic management of patients with a history of previous myocardial infarction.MethodsCross-sectional study at 6 years of a...

Cardiac Arrest and Tortuosity of Artery as Major Predictors Response of Rare Case of Spontaneous Coronary Artery Dissection

Background: Spontaneous coronary artery dissection (SCAD) may be a predictor of fibromuscular dysplasia (FMD) that affects Caucasian women, lean, between 15 and 50 years of age and with no significant historical predominance in the female sex, from 75 to 100% of cases. Within this, it is known that the main predictors of this enzymatic derangement can be postpartum periods, multiparity, tissue disorder, hormone therapies (use of anticonception), use of certain illicit drugs, physical stress and emotional stress. In smaller proportions, it is associated with disorders such as the Marfan, Ehlers-Danlos and Horner Syndromes. Objective: It was to report a rare case of spontaneous coronary dissection, with previous involvement of cardiac arrest. Case: Female patient, 40 years old, presented pain in precordial region in tightening with irradiation to left upper limb. The patient denied a history of hypertension, Diabetes mellitus, dyslipidemia and smoking, and was unable to report a family history. However, she reported an episode of sudden cardiac arrest three years before and presented with grade I obesity. She also presented tortuosity of the coronary arteries and did not report migraine headaches, and after exams (cineangiographies) she was diagnosed with SCAD. Conclusion: Due to the episode of acute myocardial infarction and the presence of coronary tortuosity, as predictors of SCAD, the patient was diagnosed with this condition and, after the treatments mentioned in the above text, the patient remained asymptomatic.

SLEEP QUALITY IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION

ABSTRACT The aim of this study was to describe sleep quality and to identify associated factors in patients hospitalized with acute myocardial infarction. A descriptive and cross-sectional study was conducted with 113 patients (70.8% men, mean age 59.7 years). An instrument was used for sociodemographic and clinical characterization and the Pittsburgh Sleep Quality Index. Results showed that 71.7% of participants had poor sleep quality and over 64% slept six hours or less per night. The presence of diabetes mellitus, depression, and absence of physical activity contributed to increase the final score of the Pittsburgh Sleep Quality Index in about 2.5 points for each variable. The identification of sleep quality and proposals of interventions to improve sleep quality must be included in the actions of nurses in order to reduce harm to patients' health before and after the acute myocardial infarction episode.

Risk of Post-TKA Acute Myocardial Infarction in Patients With a History of Myocardial Infarction or Coronary Stent.

Acute myocardial infarction (AMI) is one of the most important perioperative complications of total knee arthroplasty (TKA). Although risk-stratification tools exist for the prediction of cardiac complications including AMI after noncardiac surgery, such stratification does not differentiate the patients with a coronary stent alone, AMI without a stent, or AMI with a stent. The risk of postoperative AMI in these patient groups may vary. Several studies have recommended suitable times for noncardiac surgery in patients with a coronary stent; however, they do not differentiate between the patients with AMI and no AMI. The suitable time of noncardiac surgery for patients with AMI and stent may vary from those with a stent alone. Moreover, a study to evaluate the risk of AMI within 1 year in an Asian population with a history of AMI or coronary stent who underwent TKA has not been reported. (1) What are the risks of AMI within 1 year of TKA in patients who have had a stent alone, AMI without a stent, or AMI with a stent as compared with patients without an AMI/stent? (2) For patients with AMI/stent placement, when can TKA be performed where the risk of subsequent AMI normalizes? (3) What comorbidities are associated with post-TKA AMI? (4) Is the risk of AMI within 1 year after surgery in patients undergoing TKA without a history of AMI/stent higher than that in patients with no surgery? This study is a retrospective study of the medical claim records of 128,216 patients who underwent TKA between 1997 and 2010 in Taiwan. The records were retrieved from the research database of the Bureau of National Health Insurance in Taiwan, which maintains the records of 99.68% of the Taiwan population. The patients who had a history of AMI or coronary stent placement within the year before TKA were compared with the patients who had not experienced AMI or stent placement before TKA. The control subjects were matched according to sex, age, Charlson score, and year of surgery. There were 2413 patients in each group. The patients with a history of AMI or stent placement and the timing of TKA after coronary event were further stratified as with a coronary stent alone, AMI without a stent, and AMI with a stent. The effects of the comorbidities of renal failure, diabetes, liver failure, and hypertension were also analyzed individually. The risk of AMI within 1 year after TKA was investigated using bivariate analysis and the Cox proportional hazard model. To compare the risk of AMI within 1 year of surgery in the patients with a history of TKA and no AMI/stent with the population without a history of surgery, a similar bivariate analysis and the Cox proportional hazard model were applied to their matched case and control groups, each containing 110,980 patients. In the adjusted model, using no AMI/stent before TKA as a reference, patients having undergone AMI + stent had the highest risk (hazard ratio [HR], 5.23; 95% confidence interval [CI], 1.81-15.14; p = 0.002), AMI alone without a stent had less risk (HR, 4.88; 95% CI, 1.49-16.01; p = 0.009), and stent alone with AMI had the lowest risk (HR, 3.16; 95% CI, 1.29-7.71; p = 0.012). In all patients, risk of AMI after TKA was not different than reference values after 1 year of initial AMI or stent (stent: HR, 1.67; 95% CI, 0.71-3.94; p = 0.239; AMI: HR, 1.88; 95% CI, 0.42-8.49; p = 0.412; AMI + stent: HR, 1.91; 95% CI, 0.53-6.89; p = 0.321). The risk of post-TKA AMI was elevated within 1 year of the previous episode of AMI/stent (0-180 days: HR, 8.42; 95% CI, 3.03-23.41; p < 0.001; 181-365 days: HR, 7.52; 95% CI, 2.47-22.88; p < 0.001). Only chronic renal failure under hemodialysis was associated with increased risk of AMI within 1 year of TKA (adjusted HR, 4.34; 95% CI, 1.22-15.43; p = 0.023). Patients undergoing TKA with no history of AMI/stent had a lower risk of AMI within 1 year of TKA compared with the patients with no history of surgery (adjusted HR, 0.92; 95% CI, 0.86-0.99; p = 0.016). This study found the risk of post-TKA AMI remains high within 1 year in patients with a history of AMI/stent. It is recommended that an elective TKA should be performed at least 1 year after an episode of AMI or stent placement. Stents do not provide protection against post-TKA AMI within 6 months of the AMI and patients with AMI + stent have a higher risk of AMI than those with only AMI. Patients of AMI/stent on hemodialysis have a very high risk of post-TKA AMI. However, the risk of AMI is lower in post-TKA patients compared with those with no TKA. Level III, prognostic study.

Correlation between autonomous function and left ventricular performance after acute myocardial infarction.

Reduced ejection fraction (EF), possibly induced/mediated by autonomic abnormal activation, is one of the most powerful predictors of adverse outcome after acute myocardial infarction (MI). A deep understanding of the correlation between the autonomous functionality and the left ventricular performance in these patients is therefore of paramount importance. The autonomous function is reflected in the cardiac activity and, specifically, in the heart rate variability (HRV) signal. Given the cardiac activity nonlinearity, growing interest is being manifested towards nonlinear methods of analysis, which might provide more significant information than the traditional linear approaches. The aim of the present study was to investigate if non-linear HRV metrics change between MI patients with preserved EF (pEF) and MI patients with reduced EF (rEF). Data were acquired in the context of the cardioRisk project. Ten MI patients with rEF and six MI patients with pEF, admitted to Intensive Cardiac Care after a first acute MI episode, were studied. The ECG was acquired during a Holter recording and the tachogram was extracted. Sample entropy (SE) and Lempel-Ziv Complexity (LZC 1 and LZC 2) metrics were computed on five hour long tachogram portions. A significant correlation was found between LZC indices and EF in the whole population; SE, LZC 1 and LZC 2 were significantly higher in patients with pEF. Our results indicate that lower complexity characterizes the HRV of MI patients with rEF. Complexity reduction might be due to a simplification of regulatory mechanisms, which might explain why MI patients with rEF are at higher risk for subsequent non-fatal and fatal events.

Influence of β-blockers on heart rate recovery and rating of perceived exertion when determining training intensity for cardiac rehabilitation

BackgroundThe influence of β-blockers on heart rate recovery (HRR) and rating of perceived exertion (RPE) during Phase I cardiac rehabilitation (CR) for patients with a recent episode of acute myocardial infarction (AMI) is not clear. MethodsFrom October 2009 to July 2011, 105 patients with a recent episode of AMI who received a successful percutaneous coronary intervention were recruited into this study. Before entering Phase II CR, each patient underwent a cardiopulmonary exercise test (CPET), where RPE was assessed every minute and related parameters were recorded. ResultsThe participants entering CR had relatively low mean peak oxygen consumption (VO2max). However, the peak heart rate and VO2max were lower in those taking β-blockers. The RPE value at the ventilatory threshold (VT) was significantly higher (12.7 ± 1.7) in participants who were taking β-blockers relative to those who were not (11.5 ± 1.4). The HRR value was lower (12.5 ± 8.8) in participants who were taking β-blockers relative to those who were not (17.0 ± 9.1). ConclusionThese findings suggest that use of β-blockers increased the RPE value at the VT. In addition, HRR was attenuated by β-blockers. In patients who do not undergo CPET, the use of β-blockers should be taken into consideration when using RPE for the initial exercise prescription to determine training intensity.