Age-related increase in mortality among patients with first myocardial infarctions treated with thrombolysis. The Investigators of the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI-2)

Patient-dependent variables affecting treatment and prediction of acute coronary syndrome are age-related

BACKGROUND

Acute coronary syndrome (ACS) prevails in older patients and is associated with higher morbidity and mortality. Little is known about patient-related variables that may affect course and treatment of ACS in older vs. younger with acute chest pain.

METHODS

Situational, circumstantial, and other patient-related variables were assessed in 1000 unselected consecutive older (> or =70 years) and younger (<70 years) patients admitted with chest pain and possible ACS.

RESULTS

In 182 older vs. 818 younger patients, prevalence of females, those not speaking the local language, living alone, lower education level, non-smokers, diabetes, hypertension, preexisting coronary artery disease, and attempting some form of self-treatment before seeking medical help were significantly greater (P<0.001). Interval from chest pain onset to emergency department arrival was longer (P=0.05), and a higher proportion of the older considered hospitalization mandatory, suspecting ACS (P<0.001). ACS eventually developed in 19.1% of younger and 39% of older patients (P<0.001). On multivariate analysis, most predictive of ACS in the younger group were: preexisting coronary artery disease (OR 5.27; 95% CI 3.44-8.07, P<0.001), current smoking (OR 1.78; 95% CI 1.16-2.75, P=0.002), male sex (OR 1.57; 95% CI 1.0-2.59, P=0.07), and older age (OR 1.25; 95% CI 1.11-1.42, P=0.005). In the older group, these were: not speaking the local language (OR 2.39; 95% CI 1.19-4.79, P=0.005), preexisting coronary artery disease (OR 1.95; 95% CI 1.0-3.87, P=0.026), direct emergency department arrival (OR 1.9; 95% CI 1.0-3.77, P=0.066), and diabetes (OR 1.84; 95% CI 1.0-3.56, P=0.079).

CONCLUSIONS

We defined age-associated differences in patient-related variables that may predict ACS and affect treatment negatively. These variables might improve risk stratification upon hospitalization.

Aging and cardioprotection

Advanced age is a strong independent predictor for death, disability, and morbidity in patients with structural heart disease. With the projected increase in the elderly population and the prevalence of age-related cardiovascular disabilities worldwide, the need to understand the biology of the aging heart, the mechanisms for age-mediated cardiac vulnerability, and the development of strategies to limit myocardial dysfunction in the elderly have never been more urgent. Experimental evidence in animal models indicate attenuation in cardioprotective pathways with aging, yet limited information is available regarding age-related changes in the human heart. Human cardiac aging generates a complex phenotype, only partially replicated in animal models. Here, we summarize current understanding of the aging heart stemming from clinical and experimental studies, and we highlight targets for protection of the vulnerable senescent myocardium. Further progress mandates assessment of human tissue to dissect specific aging-associated genomic and proteomic dynamics, and their functional consequences leading to increased susceptibility of the heart to injury, a critical step toward designing novel therapeutic interventions to limit age-related myocardial dysfunction and promote healthy aging.

Age-Related Vascular Stiffness and Left Ventricular Size After Myocardial Infarction

Aortic stiffness increases with age and may contribute to adverse remodeling after myocardial infarction (MI). The authors examined whether vascular stiffness affects left ventricular (LV) size after MI using contrast-enhanced cardiac magnetic resonance imaging. Despite similar infarct sizes, patients aged 60 years or older (n=30) had a lower ejection fraction (42+/-15 vs 53+/-11%, P<.01) and greater end-systolic volume index (75+/-47 vs 44+/-18 mL/m(2), P<.01) than younger patients (n=19). As infarct size increased, LV end-systolic volumes (P<.0001) and ejection fraction (P<.0001) in the older participants were progressively greater. Participants with greater aortic stiffness had greater end-systolic volume indices (P<.0001) and lower ejection fraction (P<.0001) with increasing infarct size. Using multivariate analysis, MI size (P<.001) and aortic distensibility (P=.02) were significant predictors of end-systolic volume index. Older patients have increased LV size after MI compared with younger patients, possibly related to age-related decreases in aortic distensibility affecting LV remodeling.

Acute Coronary Care in the Elderly, Part II

Background— Age is an important determinant of outcomes for patients with acute coronary syndromes. However, community practice reveals a disproportionately lower use of cardiovascular medications and invasive treatment even among elderly patients who would stand to benefit. Limited trial data are available to guide care of older adults, which results in uncertainty about benefits and risks, particularly with newer medications or invasive treatments and in the setting of advanced age and complex health status.

Methods and Results— Part II of this American Heart Association scientific statement summarizes evidence on presentation and treatment of ST-segment–elevation myocardial infarction in relation to age (<65, 65 to 74, 75 to 84, and ≥85 years). The purpose of this statement is to identify areas in which the evidence is sufficient to guide practice in the elderly and to highlight areas that warrant further study. Treatment-related benefits should rise in an elderly population, yet data to confirm these benefits are limited, and the heterogeneity of older populations increases treatment-associated risks. Elderly patients with ST-segment–elevation myocardial infarction more often have relative and absolute contraindications to reperfusion, so eligibility for reperfusion declines with age, and yet elderly patients are less likely to receive reperfusion even if eligible. Data support a benefit from reperfusion in elderly subgroups up to age 85 years. The selection of reperfusion strategy is determined more by availability, time from presentation, shock, and comorbidity than by age. Additional data are needed on selection and dosing of adjunctive therapies and on complications in the elderly. A “one-size-fits-all” approach to care in the oldest old is not feasible, and ethical issues will remain even in the presence of adequate evidence. Nevertheless, if the contributors to treatment benefits and risks are understood, guideline-recommended care may be applied in a patient-centered manner in the oldest subset of patients.

Conclusions— Few trials have adequately described treatment effects in older patients with ST-segment–elevation myocardial infarction. In the future, absolute and relative risks for efficacy and safety in age subgroups should be reported, and trials should make efforts to enroll the elderly in proportion to their prevalence among the treated population. Outcomes of particular relevance to the older adult, such as quality of life, physical function, and independence, should also be evaluated, and geriatric conditions unique to this age group, such as frailty and cognitive impairment, should be considered for their influence on care and outcomes. With these efforts, treatment risks can be minimized, and benefits can be placed within the health context of the elderly patient.

Subacute left ventricle free wall rupture after acute myocardial infarction: awareness of the clinical signs and early use of echocardiography may be life-saving

Left ventricular free wall rupture (LVFWR) is a fearful complication of acute myocardial infarction in which a swift diagnosis and emergency surgery can be crucial for successful treatment. Because a significant number of cases occur subacutely, clinicians should be aware of the risk factors, clinical features and diagnostic criteria of this complication. We report the case of a 69 year-old man in whom a subacute left ventricular free wall rupture (LVFWR) was diagnosed 7 days after an inferior myocardial infarction with late reperfusion therapy. An asymptomatic 3 to 5 mm saddle-shaped ST-segment elevation in anterior and lateral leads, detected on a routine ECG, led to an urgent bedside echocardiogram which showed basal inferior-wall akinesis, a small echodense pericardial effusion and a canalicular tract from endo to pericardium, along the interface between the necrotic and normal contracting myocardium, trough which power-Doppler examination suggested blood crossing the myocardial wall. A cardiac MRI further reinforced the possibility of contained LVFWR and a surgical procedure was undertaken, confirming the diagnosis and allowing the successful repair of the myocardial tear. This case illustrates that subacute LVFWR provides an opportunity for intervention. Recognition of the diversity of presentation and prompt use of echocardiography may be life-saving.

Age, outcomes, and treatment effects of fibrinolytic and antithrombotic combinations: findings from Assessment of the Safety and Efficacy of a New Thrombolytic (ASSENT)-3 and ASSENT-3 PLUS

BACKGROUND

Elderly patients with acute myocardial infarction are at particularly high risk for death and bleeding complications. The efficacy and safety of antithrombotic strategies in these patients remain unclear.

METHODS

To provide more insight into the risk and benefit of antithrombotic strategies in the elderly, we examined patients from the ASSENT-3 and ASSENT-3 PLUS trials with STEMI who were treated with tenecteplase (TNK) and unfractionated heparin (UFH) or enoxaparin, or half-dose TNK with abciximab and reduced-dose UFH.

RESULTS

Older patients had a higher risk profile, and lower use of concomitant therapies and revascularization procedures. We found an interaction between age and treatment effect for the efficacy end point (P = .0007) and the efficacy plus safety end point (P < .0001). Younger patients (<65 years) had a lower risk of the composite efficacy plus safety end point with enoxaparin (relative risk [RR] 0.84, 95% CI 0.74-0.94) or abciximab (RR 0.79, 95% CI 0.69-0.90) compared with UFH. In patients >65 years of age, the benefit of enoxaparin appeared to be offset by an increased risk of bleeding complications. The risk of the efficacy plus safety end point tended to be higher in elderly patients receiving abciximab and half-dose TNK (RR 1.18, 95% CI 0.91-1.51 for 76-85 years of age and RR 1.48, 95% CI 0.88-2.49 for >85 years of age).

CONCLUSIONS

Although TNK with either enoxaparin or abciximab appeared to be more effective than with standard UHF in younger patients, these combinations tended to be less effective and even may be unsafe in the elderly. Development of new combination strategies and dosing schemes of fibrinolytics and antithrombotics with improved efficacy and safety in the elderly remains a high priority.

Use and efficacy of abciximab in an unselected population with acute myocardial infarction treated with primary angioplasty: data from AMI-Florence registry

AIMS

We sought to evaluate the determinants and the potential benefit of abciximab use in unselected patients with acute myocardial infarction treated with primary angioplasty.

METHODS AND RESULTS

Based on the AMI-Florence registry, we analyzed 461 consecutive acute myocardial infarction patients treated with primary angioplasty, 280 (61%) of whom received abciximab. For each patient, a propensity score indicating the likelihood of abciximab treatment was calculated. Compared to those not treated, patients treated with abciximab were at lower risk. At multivariate analysis, the direct admission to a hospital with angioplasty facilities significantly increased the probability of receiving abciximab (OR 1.99, 95% CI 1.30-3.03, p=.001), while older age (OR 0.97, 95% CI 0.95-0.98, p<.0001), non-anterior location (OR 0.58, 95% CI 0.38-0.88, p=.011) and Killip class >1 (OR 0.53, 95% CI 0.32-0.87, p=.013), were negative predictors of abciximab use. Primary angioplasty had a higher success rate in patients treated with abciximab (99.3% versus 96.5%, p=.03). In-hospital and 1-year mortality were significantly lower in patients treated with abciximab (2.5% versus 13.3%, p<.0001, and 7% versus 21%, p<.0001, respectively). At multivariate analysis patients treated with abciximab had a significantly lower risk of in-hospital mortality (OR 0.35, 95% CI 0.14-0.93, p=.035), and a marginally lower risk of death at 1-year follow-up (HR 0.58, 95% CI 0.32-1.03, p=.065). These results did not change when the propensity score was included into the analyses.

CONCLUSIONS

In the real practice, abciximab is more frequently used in patients at lower risk, particularly when directly admitted to a hospital with angioplasty facilities. Abciximab use is associated with a significant reduction in early mortality. A trend toward a reduced mortality is maintained also at 1 year.

Short-term caloric restriction improves ischemic tolerance independent of opening of ATP-sensitive K+ channels in both young and aged hearts

Ischemic tolerance decreases with aging and the cardioprotective effect of ischemic preconditioning (IPC) is impaired in aged animals. Although lifelong caloric restriction (CR) profoundly affects the physiological and pathophysiological modifications induced by aging and markedly increases life span in several species, it is unclear whether short-term CR affects ischemic tolerance and IPC in aged hearts. Six-month-old (Y) and 24-month-old (O) Fischer 344 male rats were randomly divided into two groups; AL rats were fed ad libitum, whereas CR rats were fed 90% of the caloric intake of AL for 2 weeks followed by 65% of the caloric intake for 2 weeks. Isolated perfused hearts were subjected to 25 min of ischemia followed by 30 min of reperfusion with or without IPC. The recovery of LV function after reperfusion improved with IPC in ALY but not in ALO. CR improved the recovery of LV function in both CRY and CRO but the cardioprotective effect of IPC was not additive to that of CR. Neither 5-hydroxydecanoate nor glibenclamide abrogated the protective effect of CR in either CRY or CRO. The recovery of myocardial high-energy phosphates after reperfusion was better with CR in both generations. There was no difference in myocardial expression levels of AMP-activated kinase (AMPK) but AMPK-alpha phosphorylated at Thr172 increased with CR in both Y and O. In conclusion, short-term CR improves myocardial ischemic tolerance independent of the opening of KATP channels in both Y and O. CR-induced cardioprotection is associated with an increase in activated AMPK.

What is the optimal reperfusion strategy for elderly patients with acute MI?

The overview of the Fibrinolytic Therapy Trialists' (FTT) Collaborative Group showed that, in more than 3000 elderly patients, thrombolytic treatment is effective in reducing mortality of patients with acute myocardial infarction with ST elevation within 12 hours from the onset of symptoms. Small-scale clinical trials confirmed the superiority of primary percutaneous coronary intervention even in older patients. However, clinical practice largely differs from the setting of clinical trials and, specifically, with respect to primary percutaneous coronary intervention. As a consequence, the results observed with percutaneous coronary intervention in "real world" patients seem to be less favorable than those obtained in trials. For this reason, reperfusion therapy with fibrinolytic agents remains the first choice of therapy for ST elevation myocardial infarction in the majority of hospitals where direct percutaneous coronary intervention facilities are not available.

Incremental Prognostic Value of Stress Echocardiography Over Clinical and Stress Electrocardiographic Variables in Patients With Prior Myocardial Infarction: "Warranty Time" of a Normal Stress Echocardiogram

BACKGROUND

Patients with prior myocardial infarction (MI) are at increased risk of subsequent cardiac events (MI or cardiac death). The incremental prognostic value and warranty time of a normal stress echocardiogram in this high-risk population is not well defined.

METHODS

We evaluated 251 consecutive patients (62 +/- 11 years; 64% males) with remote history of MI (>6 weeks) undergoing stress echocardiography (83% dobutamine). Ischemia was defined as a new reversible wall motion abnormality and/or biphasic response. Follow-up for up to 4 years (mean 2.9 +/- 1.0 years) for confirmed MI (n = 7) and cardiac death (n = 15) were obtained.

RESULTS

Stress echocardiography effectively risk stratified patients into normal versus abnormal subgroups (Event rate 0.8% per year vs 4.2% per year; P = 0.01; RR = 5.6, 95% CI = 1.3-24.7). In patients with a normal stress echocardiogram, the event rate at the end of 6, 12, and 18 months were <1% per year. After 18 months the event rate in patients with a normal stress echocardiogram increased greatly (>1% per year). Stress echocardiography yields incremental prognostic value over clinical and stress electrocardiographic variables (Global chi-square increased from 12.4 to 25 to 31.1, P < 0.0001 both groups).

CONCLUSIONS

Stress echocardiography yields appropriate risk stratification and prognosis and provides incremental prognostic value over clinical and stress electrocardiographic variables even in patients with prior MI. A normal stress echocardiogram portends a benign prognosis (<1% event rate/year) for up to 18 months.

Prehospital care pathway delays: gender and myocardial infarction

AIM

This paper reports the findings of a study that identified gender specific prehospital care pathway delays amongst Irish women and men with myocardial infarction.

BACKGROUND

Women are more likely to experience a poorer prognosis than their male counterparts following hospitalization for myocardial infarction, yet research shows that women continue to experience prehospital care pathway delays.

METHODS

A 1-year prospective census was carried in six major academic teaching hospitals in Dublin, Ireland in 2001-2002. A total of 277 (31%) female and 613 (69%) male patients with confirmed myocardial infarction were included in the study.

RESULTS

Women were more likely to experience prolonged 'initial symptom-onset to A&E delays' (14 hours vs. 2.8 hours P < 0.0001), and 'intense symptom-onset to A&E delays' (3.1 hours vs. 1.8 hours , P < 0.0001), i.e. arrival at a hospital accident and emergency department. Advancing age was associated with greater prehospital delays (P < 0.0001), whilst patients with private health insurance had shorter delays than public patients (without private health insurance) or those with medical cards (entitling them to means-tested medical benefits) (P = 0.001). Patients who drove themselves by car to hospital had shorter median prehospital times than those arriving by any other admission mode (P < 0.0001), whilst those referred by their general practitioner had longer delays than those who were self-referred (5 hours vs. 1.7 hours, P < 0.0001).

CONCLUSIONS

Female gender, advancing age, referral source, insurance status and mode of transport to hospital are independent factors contributing to prehospital patient delays. Nurses who care for patients with coronary artery disease have a unique opportunity to educate people about the most appropriate action to be taken in the event of experiencing symptoms.

Which strategy should be used for acute ST-elevation myocardial infarction in patients aged more than 75 years?

The optimal management of acute myocardial infarction in elderly people (>or= 75 years) is controversial because elderly patients have been excluded or are under-represented in most acute myocardial infarction trials. Randomized studies show that, also in the elderly, thrombolytic therapy is effective in reducing mortality after acute myocardial infarction but the benefit in terms of mortality, recurrent infarction and stroke is smaller compared to primary percutaneous coronary intervention. Among the available mechanical therapeutic strategies, stenting is found to be superior to balloon angioplasty, whereas the role of drug-eluting stents in this setting still remains to be evaluated. The standard use of intravenous unfractionated heparin is still recommended because of the increased risk of intracranial haemorrhage by a combination of low molecular weight heparin or IIb/IIIa inhibitors and thrombolytic agents. Dedicated randomized clinical trials are needed to establish the best reperfusion therapy for this expanding population, especially in patients admitted to hospitals without percutaneous coronary intervention facilities and in patients developing cardiogenic shock.

Outcome of Primary Percutaneous Coronary Intervention in Octogenarians with Acute Myocardial Infarction

BACKGROUND/PURPOSE

Acute myocardial infarction (AMI) results in more complications and increased mortality in octogenarians compared to patients in younger age groups. This study investigated the short- and long-term outcomes in octogenarians after primary percutaneous coronary intervention (PCI).

METHODS

During the study period from May 1997 to August 2004, 54 patients > or = 80 years old with ST-elevation myocardial infarction (STEMI) were eligible for primary PCI. Data collected included baseline clinical characteristics and usage of cardiovascular medications. Diagnostic coronary angiography and revascularization procedures were performed using standard practices. During hospitalization, the clinical course including serial changes in cardiac enzymes, adverse events associated with myocardial infarction or treatment, and inhospital or long-term mortality of patients were recorded.

RESULTS

The mean age of the 54 patients (35 men, 19 women) was 82.8 +/- 2.5 years (range, 80-89 years). Among them, 27 (50%) had anterior infarction, six (11%) had anterolateral infarction, and 21 (39%) had inferior infarction, inclusive of three patients with accompanying right ventricular infarction. Among them, 20 (37%) patients were in Killip class I, nine (17%) were in class II, two (4%) in class III, and 23 (43%) in class IV. The mean delay from onset of symptoms to arrival in hospital was 220 +/- 167 minutes, and 189 +/- 169 minutes from hospital arrival to reperfusion. Diagnostic coronary angiography revealed that 48 (89%) patients had multivessel disease. Inhospital death occurred in 23 (43%) patients, with the leading causes of death being profound cardiogenic shock (61%), and free wall rupture (26%).

CONCLUSION

Octogenarian patients who developed STEMI tended to have multivessel disease. These patients had a high inhospital mortality rate that was most likely to be due to cardiogenic shock.

Lifestyle and Prevention of Cardiovascular Disease in the Elderly: An Italian Perspective

The life span of human beings is partially influenced by genetic factors, but outcomes of aging are profoundly influenced by lifestyle and other environmental factors. Age-related modifications of the cardiovascular system are preserved by antiaging lifestyle interventions such as physical activity and caloric restriction. Accordingly, physical activity and low body mass index reduce mortality in older men with cardiovascular diseases. Several mechanisms have been proposed to explain the protective effect of lifestyle interventions against cardiovascular diseases in the elderly, including a reduction of vulnerability (i.e., the age-related reduction of endogenous mechanisms protective against pathologic insults). The age-related reduction of ischemic preconditioning, the most powerful endogenous protective mechanism against myocardial ischemia, is restored by both physical activity and caloric restriction. Thus, older persons can implement lifestyle practices that minimize their risk of death from cardiovascular diseases.

Myocardial aging

This review questions the old paradigm that describes the heart as a post-mitotic organ and introduces the notion of the heart as a self-renewing organ regulated by a compartment of multipotent cardiac stem cells (CSCs) capable of regenerating myocytes and coronary vessels throughout life. Because of this dramatic change in cardiac biology, the objective is to provide an alternative perspective of the aging process of the heart and stimulate research in an area that pertains to all of us without exception. The recent explosion of the field of stem cell biology, with the recognition that the possibility exists for extrinsic and intrinsic regeneration of myocytes and coronary vessels, necessitates reevaluation of cardiac homeostasis and myocardial aging. From birth to senescence, the mammalian heart is composed of non-dividing and dividing cells. Loss of telomeric DNA is minimal in fetal and neonatal myocardium but rather significant in the senescent heart. Aging affects the growth and differentiation potential of CSCs interfering not only with their ability to sustain physiological cell turnover but also with their capacity to adapt to increases in pressure and volume loads. The recognition of factors enhancing the activation of the CSC pool, their mobilization, and translocation, however, suggests that the detrimental effects of aging on the heart might be prevented or reversed by local stimulation of CSCs or the intramyocardial delivery of CSCs following their expansion and rejuvenation in vitro. CSC therapy may become, perhaps, a novel strategy for the devastating problem of heart failure in the old population.

Influence of gender on treatment and short-term mortality of patients with acute myocardial infarction in Berlin

AIMS

Previous studies have shown higher hospital mortality rates in women, especially younger women, than in men. In light of the fact that myocardial infarction therapy is rapidly developing, and since gender-specific aspects have been discussed in detail during recent years, it was our goal to re-evaluate factors influencing hospital mortality rate, especially those involving gender-specific differences, in the city of Berlin, Germany.

METHODS

We prospectively collected data from 5133 patients (3330 men and 1803 women) with acute myocardial infarction who were treated in 25 hospitals in Berlin during the years 1999 to 2002.

RESULTS

During hospitalization the overall mortality rate was 18.6% among women and 8.4% among men. Women were older (mean age for men 62 years; women 73 years) and less likely to be married (men 74.6%; women 36.9%) than men. Women generally took longer to arrive at the hospital after infarction than did men (median time: men 2.0 h; women 2.6 h). Women furthermore demonstrated a higher proportion of diabetes (men 22.8%; women 36.5%) and hypertension (men 58.0%; women 69.3%). Reperfusion therapy (men 68.8%; women 49.7%) and administration of beta-blockers (men 76.0%; women 66.0%) took place less often for women than for men. A multivariate analysis revealed the following factors to be independent predictors of hospital mortality: age, gender, diabetes mellitus, hypercholesterolemia, pre-existing heart failure, pre-hospital cardiopulmonary resuscitation, cardiogenic shock and pulmonary congestion on admission, admission to a hospital with >600 beds, ST-elevation in the initial ECG, reperfusion therapy, as well as beta-blocker and ACE inhibitor treatment within 48 h of hospitalization.

CONCLUSION

Even after adjustment in multivariate analysis, women with acute myocardial infarction still demonstrate a higher risk for in-hospital death than men.

Equally valid models gave divergent predictions for mortality in acute myocardial infarction patients in a comparison of logistic [corrected] regression models

OBJECTIVE

Models that predict mortality after acute myocardial infarction (AMI) contain different predictors and are based on different populations. We studied the agreement and validity of predictions for individual patients.

STUDY DESIGN AND SETTING

We compared predictions from five predictive logistic regression models for short-term mortality after AMI. Three models were developed previously, and two models were developed in the GUSTO-I data, where all five models were applied (n =40,830, 7.0% 30-day mortality). Agreement was studied with weighted kappa statistics of categorized predictions. Validity was assessed by comparing observed frequencies with predictions (indicating calibration) and by the area under the receiver operating characteristic curve (AUC), indicating discriminative ability.

RESULTS

The predictions from the five models varied considerably for individual patients, with low agreement between most (kappa <0.6). Risk predictions from the three previously developed models were on average too high, which could be corrected by re-calibration of the model intercept. The AUC ranged from 0.76-0.78 and increased to 0.78-0.79 with re-estimated regression coefficients that were optimal for the GUSTO-I patients. The two more detailed GUSTO-I based models performed better (AUC approximately 0.82).

CONCLUSION

Models with different predictors may have a similar validity while the agreement between predictions for individual patients is poor. The main concerns in the applicability of predictive models for AMI should relate to the selected predictors and average calibration.

Influence of reperfusion therapy on prognosis in patients aged >or=89 years with acute myocardial infarction

There is no evidence on the efficacy of reperfusion therapies on nonagenarian patients who have acute myocardial infarction. The present study suggests that such therapies may not be useful and that thrombolysis may even be harmful.

Effect of thrombolytic therapy on the risk of cardiac rupture and mortality in older patients with first acute myocardial infarction†

AIMS

To evaluate the effect of thrombolysis on mortality and its causes in older patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

An analysis of 706 consecutive patients > or =75 years old with a first AMI enrolled in the PPRIMM75 registry showed that although there were important differences in baseline characteristics among patients treated with thrombolysis, primary angioplasty (PA) and those who did not receive reperfusion therapy, 30 day mortality did not differ (29, 25, and 32%, respectively). The main cause of death in patients treated with thrombolysis was cardiac rupture (54%), whereas most of the other patients died in cardiogenic shock. Patients who received thrombolysis had a higher (P<0.0001) incidence of free wall rupture (FWR) (17.1%) compared with those who did not receive reperfusion therapy (7.9%) or who underwent PA (4.9%). By multivariable analysis, patients treated with thrombolytic therapy (TT) showed an excess risk of FWR (OR, 3.62; 95% CI, 1.79-7.33), a hazard not observed in patients who underwent PA. When compared with patients who did not receive reperfusion therapy, the odds ratio of 30 day mortality was 1.07 (95% CI, 0.65-1.76) for patients treated with thrombolysis and 0.78 (95% CI, 0.45-1.34) for those who underwent PA. The figures for 24 month mortality were 0.78 (95% CI, 0.65-1.76) and 0.67 (95% CI, 0.28-0.81), respectively.

CONCLUSION

Treatment of first AMI with TT increases the risk of FWR in very old patients, a risk not observed in patients treated with PA.

Effects of age, period and cohort on acute myocardial infarction mortality in Hong Kong

BACKGROUND

Hong Kong has been experiencing a transition from a developing area to a developed area over the past few decades. The time trends of acute myocardial infarction (AMI) mortality would have implications for the future trends of AMI in Mainland China.

METHODS

Age-adjusted mortality rates during the period 1976-1999 were calculated by direct standardization with the world population using local mortality and population data. Log-linear regressions were used to estimate the annual percentage changes in mortality over different periods. Poisson regression models were used to explore the effects of age, calendar period and birth cohort.

RESULTS

A downward trend was observed for age-adjusted AMI mortality rate in both sexes in the 1990s, after the increasing trends in the 1970s and 1980s. The AMI mortality rate among men and women dropped by 36.4% and 37.4%, respectively. A negative annual percentage change was observed across all age groups in both sexes. Both the calendar period and the birth cohort showed significant effects on the changing AMI mortality rate, with the influence of period being stronger than the cohort, especially among males.

CONCLUSION

Age-adjusted AMI mortality started to decrease during the last decade. Changing life styles and a reduction of coronary risk factors could have contributed, but the improvements in medical care and effective treatment for patients suffering from AMI should have an important role.

Tandem action of exercise training and food restriction completely preserves ischemic preconditioning in the aging heart

Ischemic preconditioning (IP) has been proposed as an endogenous form of protection against ischemia reperfusion injury. IP, however, does not prevent post-ischemic dysfunction in the aging heart but may be partially corrected by exercise training and food restriction. We investigated the role of exercise training combined with food restriction on restoring IP in the aging heart. Effects of IP against ischemia-reperfusion injury in isolated hearts from adult (A, 6 months old), sedentary 'ad libitum' fed (SL), trained ad libitum fed (TL), sedentary food-restricted (SR), trained- and food-restricted senescent rats (TR) (24 months old) were investigated. Norepinephrine release in coronary effluent was determined by high performance liquid cromatography. IP significantly improved final recovery of percent developed pressure in hearts from A (p<0.01) but not in those from SL (p=NS) vs unconditioned controls. Developed pressure recovery was partial in hearts from TL and SR (64.3 and 67.3%, respectively; p<0.05 vs controls) but it was total in those from TR (82.3%, p=NS vs A; p<0.05 vs hearts from TL and SR). Similarly, IP determined a similar increase of norepinephrine release in A (p<0.001) and in TR (p<0.001, p=NS vs adult). IP was abolished by depletion of myocardial norepinephrine stores by reserpine in all groups. Thus, IP reduces post-ischemic dysfunction in A but not in SL. Moreover, IP was preserved partially in TR and SR and totally in TR. Complete IP maybe due to full restoration of norepinephrine release in response to IP stimulus.

Prognostic significance of the long pentraxin PTX3 in acute myocardial infarction

BACKGROUND

Inflammation has a pathogenetic role in acute myocardial infarction (MI). Pentraxin-3 (PTX3), a long pentraxin produced in response to inflammatory stimuli and highly expressed in the heart, was shown to peak in plasma approximately 7 hours after MI. The aim of this study was to assess the prognostic value of PTX3 in MI compared with the best-known and clinically relevant biological markers.

METHODS AND RESULTS

In 724 patients with MI and ST elevation, PTX3, C-reactive protein (CRP), creatine kinase (CK), troponin T (TnT), and N-terminal pro-brain natriuretic peptide (NT-proBNP) were assayed at entry, a median of 3 hours, and the following morning, a median of 22 hours from symptom onset. With respect to outcome events occurring over 3 months after the index event, median PTX3 values were 7.08 ng/mL in event-free patients, 16.12 ng/mL in patients who died, 9.12 ng/mL in patients with nonfatal heart failure, and 6.88 ng/mL in patients with nonfatal residual ischemia (overall P<0.0001). Multivariate analysis including CRP, CK, TnT, and NT-proBNP showed that only age > or =70 years (OR, 2.11; 95% CI, 1.04 to 4.31), Killip class >1 at entry (OR, 2.20; 95% CI, 1.14 to 4.25), and PTX3 (>10.73 ng/mL) (OR, 3.55; 95% CI, 1.43 to 8.83) independently predicted 3-month mortality. Biomarkers predicting the combined end point of death and heart failure in survivors were the highest tertile of PTX3 and of NT-proBNP and a CK ratio >6.

CONCLUSIONS

In a representative contemporary sample of patients with MI with ST elevation, the acute-phase protein PTX3 but not the liver-derived short pentraxin CRP or other cardiac biomarkers (NT-proBNP, TnT, CK) predicted 3-month mortality after adjustment for major risk factors and other acute-phase prognostic markers.

Predictors of intracranial hemorrhage with fibrinolytic therapy in unselected community patients: a report from the FASTRAK II project

BACKGROUND

Patients at high risk for intracranial hemorrhage (ICH) are generally excluded from thrombolytic trials. Because the frequency and predictors of ICH reported from these studies may not be widely applicable, we sought to examine this matter further in unselected patients with acute myocardial infarction in the community.

METHODS

FASTRAK II is a prospective ongoing registry of acute coronary syndromes involving 111 Canadian hospitals. Trained medical personnel recorded admission, treatment, and discharge data on patients admitted with acute coronary syndromes.

RESULTS

From January 1, 1998, to December 31, 2000, 12,739 patients received fibrinolytic therapy for acute myocardial infarction. Of these, 146 patients (1.15%) sustained strokes and 82 patients (0.65%) had an ICH. Advanced age, female sex, history of cerebrovascular event, and systolic hypertension on arrival (systolic blood pressure >160 mm Hg) were identified with a multivariate logistic regression model to be important independent risks factors for ICH. Patients receiving streptokinase had a lower risk of ICH. Among the patients at high risk for ICH, the ICH rates remained low, ranging from 0.7% to 1.8%.

CONCLUSION

ICH is an infrequent event after fibrinolytic therapy in ST-elevation MI; this low rate supports broad penetration of this therapy. Simple clinical characteristics are useful in predicting the risk of ICH and allow a clinician to individualize the risk-benefit assessment of this therapy.

Reduced collateral circulation to the infarct-related artery in elderly patients with acute myocardial infarction

OBJECTIVES

The purpose of this study was to investigate the hypothesis that circulation via collateral vessels to an infarct-related artery (IRA) is impaired with aging in patients with acute myocardial infarction (AMI).

BACKGROUND

Animal experiments have shown that advanced age blunts the development of new vessels in response to angiogenic cytokines.

METHODS

Of 3,573 consecutive patients with AMI, 1,934 patients who fulfilled the following criteria were enrolled in this study: 1) coronary angiograms were obtained within 72 h after the onset of AMI; and 2) IRA showed complete occlusion (Thrombolysis In Myocardial Infarction [TIMI] flow grade 0 or 1). Collaterals to the IRA were angiographically evaluated using the Rentrop score. Rentrop scores 1 to 3 were defined as demonstrating significant collaterals.

RESULTS

The prevalence of collaterals decreased with age, from 47.9%, 45.8%, 43.4%, to 34.0% in patients <50 years, 50 to 59 years, 60 to 69 years, > or =70 years, respectively (p < 0.001). Advanced age was an independent factor predicting the absence of collateral circulation to the IRA. In contrast, time to catheterization, history of angina pectoris, and preinfarction angina were independent predictors for the presence of collaterals. Multivariate analysis showed that the absence of collaterals was an independent predictor of in-hospital mortality in elderly patients > or =70 years (odds ratio, 15.6; 95% confidence interval, 3.5 to 69.6), although this finding was not significant in patients <70 years.

CONCLUSIONS

Advanced age is associated with decreased angiographic presence of collaterals to the IRA in patients with AMI. This abnormality may contribute to the poor prognosis of elderly patients with AMI.

Outcome in Elderly Patients Undergoing Primary Coronary Intervention for Acute Myocardial Infarction

Background— Biological age is a strong determinant of prognosis in patients with acute myocardial infarction (AMI). We sought to examine the impact of age after primary percutaneous coronary intervention in AMI and to determine whether routine coronary stent implantation and/or platelet glycoprotein IIb/IIIa inhibitors improve clinical outcomes in elderly patients after primary angioplasty.

Methods and Results— In the CADILLAC trial, 2082 patients with AMI were randomized to balloon angioplasty, angioplasty plus abciximab, stenting alone, or stenting plus abciximab. No patient was excluded on the basis of advanced age; patients ranging from 21 to 95 years of age were enrolled. One-year mortality increased for each decile of age, exponentially after 65 years of age (1.6% for patients <55 years, 2.1% for 55 to 65 years, 7.1% for 65 to 75 years, 11.1% for patients >75 years; P <0.0001). Elderly patients also had increased rates of stroke and major bleeding compared with their younger counterparts. Among elderly patients (≥65 years), 1-year rates of ischemic target revascularization (7.0% versus 17.6%; P <0.0001) and subacute or late thrombosis (0% versus 2.2%; P =0.005) were reduced with stenting compared with balloon angioplasty. Routine abciximab administration, although safe, was not of definite benefit in elderly patients. Rates of mortality, reinfarction, disabling stroke, and major bleeding in the elderly were independent of reperfusion modality.

Conclusions— Despite contemporary mechanical reperfusion strategies, mortality, major bleeding, and stroke rates remain high in elderly patients undergoing primary percutaneous coronary intervention, outcomes that are not affected by stents or glycoprotein IIb/IIIa inhibitors. By reducing restenosis, however, stent implantation improves clinical outcomes in elderly patients with AMI.

Cost-effectiveness of interventions to reduce the thrombolytic delay for acute myocardial infarction

Objectives:The objective of the study was to estimate the costs and health benefits of a public awareness campaign aimed at shortening the delay for thrombolytic therapy in patients with acute myocardial infarction (AMI) and to estimate the incremental costs and benefits of an additional telemedicine program.

Methods and Results:By using trial data on the impact of a Swedish campaign, a model was developed to simulate the current distribution of thrombolytic delay in Denmark and the delay after a campaign. The reduction in delay was translated into reduced fatality assuming reductions from the campaign and additional effects of a telemedicine program. The costs of the campaign were based on trial data and Danish unit costs while telemedicine costs were taken from a Danish demonstration program. The analyses indicate that the awareness campaign will translate into five fewer fatal AMIs (sixty-two life years gained) and a cost per life year of DKK283,300, with both costs and benefits discounted at 5 percent. When combining the public campaign with prehospital telemedicine diagnostics, the incremental cost per life year gained was DKK854.700.

Conclusions:Programs aimed at reducing delay of thrombolysis in patients with AMI are likely to have a limited impact on AMI fatality. Information campaigns may have acceptable cost-effectiveness ratios, while telemedicine programs lead to threefold greater ratios. Whether such programs can be considered cost-effective will depend on how life year gains are valued by society.

Participation versus education: the GISSI story and beyond

Approximately 20 years ago, the Italian cardiology community realized the scientific importance and the potential impact on clinical practice of the new concept of evidence-based medicine and launched (without funds) a national megatrial, the Gruppo Italiano por lo Studio della Streptochinasi nell'Infarto Miocardico (GISSI) study. In the following 20 years, 4 GISSI trials have been carried out, and a fifth is underway. The conceptual process that followed this experience shaped the role of the medico-scientific society that sponsored these trials as an active player in research, with the public health as the common target. This process of getting together was founded on the basic principle that active participation can be much more effective and rewarding than education (a passive process). Accordingly, further studies were undertaken dealing with clinical epidemiology, observational outcome research introduced complementarily to develop lines of clinical investigation along 2 mainstreams: ischemic heart disease and heart failure. The original decision to directly sponsor countrywide research projects in critical and relevant areas of care had broader implications not only for the role of scientific societies, but more generally for the nurture of independent research, which is today widely recognized to be at risk. The articulation among experimental, observational, and evaluative protocols in which all caring physicians are allowed to be producers and authors and not simply users of knowledge can favor a cultural continuity that minimizes the risk of parallelisms and gaps between research and care.

Outcomes of thrombolytic therapy for acute myocardial infarction in women

Coronary artery disease is the leading cause of mortality in women older than 50 years of age. Thrombolytic therapy substantially reduces mortality in both women and men with ST-elevation acute myocardial infarction. However, the mortality risk reduction is somewhat lower in women, in spite of similar rates of successful coronary reperfusion after thrombolytic therapy in women and men. Hemorrhagic complications including stroke and other major bleeding appear to be more common in women, particularly elderly women. The risk of reinfarction after thrombolytic therapy also is greater in women compared with men. Because of the higher complication rates, women should be monitored closely after thrombolytic therapy. However, this lifesaving treatment should not be withheld or delayed in women when indicated.

Cardiac rupture complicating myocardial infarction

Rupture of the ventricular free wall is a leading cause of death in patients with acute myocardial infarction (MI). There are a number of risk indicators that are associated with cardiac rupture, such as female gender, old age, hypertension, and first MI. Typical symptoms of cardiac rupture are recurrent or persistent chest pain, syncope, and distension of jugular veins. Electrocardiographic signs may include sinus tachycardia, new Q-waves in 2 or more leads, persistent or recurrent ST segment elevation, deviation of expected evolutionary T-wave pattern, and electromechanical dissociation in end-stage cases. Once patients at risk have been identified using clinical symptoms and electrocardiographic signs, a fast and sensitive diagnostic test to confirm cardiac rupture is transthoracic echocardiography (TTE). New insights in the etiology of subacute myocardial rupture suggests that defective cardiac remodeling may predispose the heart for rupture. The matrix metalloproteinase (MMP) system has been shown to play an important role in cardiac extracellular matrix (ECM) remodeling and cardiac rupture. Current therapy of cardiac rupture consists mainly of surgery, and conservative management with hemodynamic monitoring, prolonged bed rest, beta-blockers, and angiotensin-converting enzyme (ACE) inhibitors in selected cases.

Impact of ST-segment resolution after primary angioplasty on outcomes after myocardial infarction in elderly patients: an analysis from the CADILLAC trial

BACKGROUND

Age is a strong independent predictor of outcomes after primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). Whether lower rates of reperfusion success contribute to the poor prognosis in elderly patients is unknown.

METHODS

A formal ST-segment analysis substudy was performed in 695 patients undergoing primary PCI for AMI in the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial. Reperfusion success (determined by the magnitude of ST-segment elevation resolution [STR] after PCI) was evaluated in 4 age groups: <50 years (n = 163), >or=50 to <60 years (n = 187), >or=60 to <70 years (n = 194), and >or=70 years (n = 151).

RESULTS

There were no differences in the age groups for angiographic procedural success (>91% in all, P =.6), postprocedural Thrombolysis in Myocardial Infarction grade 3 flow (>94%, P =.8), and the proportions of patients with complete, partial, or absent STR (P >.8). However, rates of 30-day mortality (0.6%, 1.1%, 3.6%, 6.0%, respectively) and major adverse cardiac events (MACE; 2.5%, 4.8%, 6.2% 9.3%, respectively) increased with age. Rates of mortality and MACE were also inversely related to the magnitude of STR. Absent STR (hazard ratio, 3.00; 95% CI, 1.37-6.58; P =.006) and age (hazard ratio, 1.34; 95% CI, 1.01-1.77; P =.04) were independent predictors of 30-day MACE by using multivariable modeling.

CONCLUSIONS

Lack of effective myocardial reperfusion is not a contributory mechanism responsible for the high morbidity and mortality rates observed in elderly patients. Nevertheless, advanced age and absent STR are both independent predictors of adverse outcomes after primary PCI, emphasizing the importance of successful reperfusion in the elderly population.

Mortalidad del infarto de miocardio en el registro PRIMVAC. Factores pronósticos

BACKGROUND AND OBJECTIVE

The aim of this study was to determine the mortality due to acute myocardial infarction in the coronary units from Comunidad Valenciana (Spain) and the prognostic factors associated with a higher mortality.

PATIENTS AND METHOD

Demographic characteristics, coronary risk factors, electrocardiographic ischemic signs, complications and mortality of patients with acute myocardial infarction admitted in the coronary units were collected. The study period comprised January 1995-December 1999. Death incidence was measured during coronary unit's stay. Factors associated with poor prognosis were analyzed.

RESULTS

10.213 patients entered into the study. Mean age at admission was 65 12 years. 23.8% were females (76.2% males). Global mortality in coronary units was 13.3%. Independent variables associated with higher mortality were (p < 0.05): advanced age (OR=1.06 [1.05-1.06]), female sex (OR=1.45 [1.26-1.66]), diabetes mellitus (OR=1.53 [1.35-1.74]), previous myocardial infarction (OR=1.46 [1.23-1.70]), previous angor pectoris (OR=1.29 [1.13-1.49]) and Q-wave infarction (OR=1.23 [1.03-1.43]). Factors associated with lower mortality were: hypercholesterolemia (OR=0.76 [0.66-0.78]), smoking (OR=0.65 [0.57-0.74]) and thrombolysis (OR=0.85 [0.78-0.92]).

CONCLUSIONS

At present, in the reperfusion therapy era, acute myocardial infarction has a high mortality after coronary unit admission. Several clinical factors are associated with a worse prognosis.

Body mass index and preinfarction angina in elderly patients with acute myocardial infarction

BACKGROUND

Preinfarction angina, a clinical equivalent of ischemic preconditioning, seems to protect against in-hospital death, cardiogenic shock, and the combined endpoints in adult but not in elderly patients with acute myocardial infarction. Experimental evidence indicates that caloric restriction may restore ischemic preconditioning in aged animals.

OBJECTIVE

The objective was to verify whether body mass index (BMI) influences the cardioprotective effect of preinfarction angina in the elderly.

DESIGN

We retrospectively studied 820 patients aged >/= 65 y with acute myocardial infarction by evaluating BMI and major (death and cardiogenic shock) and minor in-hospital outcomes.

RESULTS

In-hospital death, cardiogenic shock, and the combined endpoints were not significantly different between elderly patients with and without preinfarction angina. Interestingly, in-hospital death, cardiogenic shock, and the combined endpoints were significantly fewer in elderly patients with than without preinfarction angina in the subset of patients with the lowest BMI (P < 0.01, < 0.01, and < 0.01, respectively). Regression analysis showed that preinfarction angina did not protect against in-hospital death when analyzed in all patients independently of BMI, whereas it was protective in the subset of patients with the lowest BMI (odds ratio: 0.06; 95% CI: 0.00, 0.54).

CONCLUSIONS

Preinfarction angina does not protect against in-hospital death, cardiogenic shock, or the combined endpoints in elderly patients with acute myocardial infarction. With stratification by quartiles of BMI, the protective effect of preinfarction angina is preserved in elderly patients with the lowest BMI.

Targeted deletion of MMP-2 attenuates early LV rupture and late remodeling after experimental myocardial infarction

Matrix metalloproteinase-2 (MMP-2) is prominently overexpressed both after myocardial infarction (MI) and in heart failure. However, its pathophysiological significance in these conditions is still unclear. We thus examined the effects of targeted deletion of MMP-2 on post-MI left ventricular (LV) remodeling and failure. Anterior MI was produced in 10- to 12-wk-old male MMP-2 knockout (KO) and sibling wild-type (WT) mice by ligating the left coronary artery. By day 28, MI resulted in a significant increase in mortality in association with LV cavity dilatation and dysfunction. The MMP-2 KO mice had a significantly better survival rate than WT mice (56% vs. 85%, P < 0.05), despite a comparable infarct size (50 +/- 3% vs. 51 +/- 3%, P = not significant), heart rate, and arterial blood pressure. The KO mice had a significantly lower incidence of LV rupture (10% vs. 39%, P < 0.05), which occurred within 7 days of MI. The KO mice exerted less LV cavity dilatation and improved fractional shortening after MI by echocardiography. The LV zymographic MMP-2 level significantly increased in WT mice after coronary artery ligation; however, this was completely prevented in KO mice. In contrast, the increase in the LV zymographic MMP-9 level after MI was similar between KO and WT mice. MMP-2 activation is therefore considered to contribute to an early cardiac rupture as well as late LV remodeling after MI. The inhibition of MMP-2 activation may therefore be a potentially useful therapeutic strategy to manage post-MI hearts.

Implications of cigarette smoking for the management of patients with acute coronary syndromes

Smokers differ from nonsmokers in the way they present with acute coronary syndromes and in how they respond to treatment. Although smoking increases the risk of a coronary event and accelerates the progression of established atherosclerosis, paradoxically, smokers have better short-term survival after an acute myocardial infarction, mainly because they are younger and have more favorable coronary anatomy. Thrombolysis appears to be a better treatment in smokers than in nonsmokers, probably because thrombosis plays a more important role in the pathogenesis of acute coronary events in smokers. Patients who continue to smoke after angioplasty or bypass surgery have a worse outcome than nonsmokers or quitters. The 2.5- to 3-fold increase in risk for myocardial infarction or stroke in smokers compared with nonsmokers decreases exponentially after smoking cessation. By 4 years the risk is only slightly higher than the risk of a subject who never smoked.

The prognostic importance of heart failure and age in patients treated with primary angioplasty

BACKGROUND

Effective risk stratification is essential in the management of patients with acute myocardial infarction. Available models have not yet been studied and validated in patients treated with primary angioplasty for acute myocardial infarction.

METHODS

The prognostic value of heart failure defined by Killip class and age upon admission and the impact of success and failure of the angioplasty procedure was studied in 1702 consecutive patients treated with primary angioplasty.

FINDINGS

The combination of Killip class and age is a strong predictor of 30-day mortality and categorizes patients in subgroups with 30-day mortality risk ranging from 0.5 to 70%. Angioplasty failure results in a high 30-day mortality, in particular in patients with Killip class > or =II and/or age > or =70 years. A large majority of patients (72%), characterized by Killip class I and age <70 years, can be identified with a 0.5% risk of death at 30 days.

INTERPRETATION

The presence of heart failure (Killip class) and age predicts 30-day mortality in patients on their way to the catheterization laboratory for primary angioplasty. This simple and effective early risk stratification, in combination with success and failure of the primary angioplasty, can be used to direct subsequent patient management.

Primary angioplasty with routine stenting compared with thrombolytic therapy in elderly patients with acute myocardial infarction

BACKGROUND

Prior studies have yielded conflicting data on the advantage of primary angioplasty compared with thrombolysis in elderly patients with acute myocardial infarction (AMI). These studies, however, were performed before the contemporary widespread use of intracoronary stents and glycoprotien IIb/IIIa antagonists.

METHODS

We prospectively compared the outcome of 130 consecutive elderly patients (aged > or =70 years) with ST-elevation AMI who were admitted to 2 similar neighboring medical centers. Patients were assigned to receive either thrombolytic therapy with accelerated tissue-type plasminogen activator (center I) or primary angioplasty with routine stenting (center II).

RESULTS

Of the patients assigned to receive primary angioplasty, 91% underwent stenting. At 6 months, patients treated with primary angioplasty, compared with those treated with thrombolytic therapy, had a lower incidence of reinfarction (2% vs 14%, P =.053) and revascularization for recurrent ischemia (9% vs 61%, P <.001) and a significant reduction in the prespecified combined end point of death, reinfarction, or revascularization for recurrent ischemia (29% vs 93%, P <.01). Primary angioplasty remained an independent predictor of the triple combined end point after controlling for potential covariables (relative risk 0.63, 95% CI 0.38-0.84). Major bleeding complications were also significantly reduced in the primary angioplasty group (0% vs 17%, P =.03).

CONCLUSIONS

Compared with thrombolysis, primary angioplasty with routine stenting in elderly patients with AMI is associated with better clinical outcomes and a lower risk of bleeding complications.

Reperfusion in acute myocardial infarction: current concepts

Myocardial reperfusion is the treatment of choice in acute myocardial infarction. Pharmacological thrombolysis restores coronary artery patency in about two thirds of patients with acute myocardial infarction. However, mechanical reperfusion with primary angioplasty and stenting achieves higher patency rates with less complications, especially in high-risk patients. Adjunctive pharmacotherapy and new device technology may improve the outcome of primary angioplasty. Facilitated angioplasty using a combination of half-dose thrombolysis, platelet glycoprotein IIb/IIIa antagonists, and early intervention, appears to be a promising strategy for the treatment of acute myocardial infarction in the modern era. The efficacy and safety of this approach are currently evaluated in several ongoing trials.

The feasibility and safety of early discharge for low risk patients with acute myocardial infarction after successful direct percutaneous coronary intervention

There is a lack of consensus among cardiologists regarding the length of time patients should be hospitalized after an uncomplicated acute myocardial infarction (AMI) and successful direct percutaneous coronary intervention (d-PCI). The purpose of this study was to evaluate the feasibility and safety of early discharge (discharge <4 days after the procedure) for low risk patients with AMI who underwent successful d-PCI. From May 1996 through December 2001, d-PCI was performed in 898 consecutive patients with AMI. Of these 898 patients, 463 (51.6%) were stratified to be at low risk. Lower risk was defined as: (1) Killip classification < or = 2 on admission; (2) the infarct-related artery achieved normal blood flow without recurrent ischemia or reinfarction in the first 24 hours; (3) no mechanical or electrical complications after d-PCI. (4) no acute renal failure, acute stroke, or major bleeding complication; (5) no advanced congestive heart failure (defined as > or = New York Heart Association functional class 3); and (6) no sepsis. Patients who were discharged <4 days after undergoing the procedure were enrolled in group 1 (n = 266). Patients who were discharged > or = 4 days after undergoing the procedure were enrolled in group 2 (n = 197). Univariate analysis demonstrated that group 2 patients had a significantly longer hospital stay (P = 0.0001) than group 1 patients. At the first 30-day follow-up examination, there were no significant differences in the combined major cardiac events (death, recurrent isehemia, reinfarction, revascularization. or advanced congestive heart failure) between the group 1 and group 2 patients (1.50% vs 1.52%, P = 0.92). There were also no significant differences in the combined major noncardiac complications (acute stroke, acute renal failure, bleeding complications requiring blood transfusion, vascular sequelae, or sepsis) between the group 1 and group 2 patients (1.13% vs 0.51%. P = 0.89). Early discharge was feasible in a majority of the patients who experienced AMI and were at lower risk 24 hours after successful d-PCI. Thus, the patients had a shortened hospital stay and no increased risk.

Does magnesium have a role in the treatment of patients with coronary artery disease?

Hypomagnesemia is common in hospitalized patients, especially in elderly patients with coronary artery disease (CAD) and/or those with chronic heart failure. Hypomagnesemia is associated with increased all cause mortality and mortality from CAD. Magnesium supplementation improves myocardial metabolism, inhibits calcium accumulation and myocardial cell death; it improves vascular tone, peripheral vascular resistance, afterload and cardiac output, reduces cardiac arrhythmias and improves lipid metabolism. Magnesium also reduces vulnerability to oxygen-derived free radicals, improves endothelial function and inhibits platelet function, including platelet aggregation and adhesion, which potentially confers upon magnesium physiologic and natural effects similar to adenosine-diphosphate inhibitors such as clopidogrel. However, data regarding the use of magnesium in patients with acute myocardial infarction (AMI) are conflicting. Although some previous relatively small randomized clinical trials demonstrated a remarkable reduction in mortality when intravenous magnesium was administered to relatively high risk AMI patients, two recently published large-scale randomized clinical trials (the Fourth International Study of Infarct Survival [ISIS 4] and Magnesium in Coronaries [MAGIC]) were unable to demonstrate any advantage of intravenous magnesium over placebo. Nevertheless, the theoretical benefits of magnesium supplementation as a cardio-protective agent in CAD patients, promising results from animal and human studies, its relatively low-cost and ease of handling requiring no special expertise, together with its excellent tolerability, gives magnesium a place in treating CAD patients, especially in those at high risk, such as CAD patients with heart failure, the elderly and hospitalized patients with hypomagnesemia. Furthermore, magnesium therapy is indicated in life-threatening ventricular arrhythmias such as torsades de pointes and intractable ventricular tachycardia.

In-hospital outcome in octogenarians with acute coronary syndrome undergoing emergent coronary angiography

Very elderly patients have higher mortality rates than younger patients after acute coronary syndrome (ACS). However, the mechanism by which increasing age contributes to such mortality remains unclear. In addition, the efficacy and safety of invasive coronary procedures for octogenarians with ACS have not been well established. We compared the clinical characteristics and in-hospital outcome of 193 octogenarians (mean age, 83 years) with those of 1,462 younger patients (mean age, 64 years) with ACS who underwent emergent coronary angiography. Octogenarians included a greater number of females, had higher rates of cerebrovascular disease and multivessel disease, a higher Killip class, a higher Forrester class, and lower rates of smoking, diabetes, and hypercholesterolemia than the younger subjects. Interventions, including percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG), were performed less frequently in octogenarians than in younger patients (88.0% versus 90.8%). The procedural success rate in octogenarians did not differ from that in younger patients. However, the in-hospital mortality rate for the octogenarians was about three times higher than for the younger patients (19.2% versus 6.9%). Multivariate analysis revealed that the predictors of in-hospital mortality in the octogenarians were a higher Killip class and a higher Forrester class. Octogenarians with ACS had fewer coronary risk factors and a similar success rate for the intervention, but had more greatly impaired hemodynamics and higher in-hospital mortality than the younger patients. Therefore, impaired myocardial reserve may contribute to a large portion of in-hospital deaths in octogenarians with ACS.

Influence of age on outcomes in patients undergoing mitral valve replacement

BACKGROUND

Although increasing age has been associated with greater risk of mortality for patients undergoing mitral valve replacement, it is less clear whether this elevated risk is related to age-related differences in comorbidity or other clinical characteristics.

METHODS

A population of 31,688 patients from The Society of Thoracic Surgeons National Cardiac Database undergoing mitral valve replacement either alone or in combination with coronary artery bypass grafting or tricuspid surgical procedures from 1997 to 2000 was examined to assess age-related variation in clinical features, morbidity, and mortality. Multivariable logistic regression was used to determine the effect of age after adjusting for other known risk factors. A classification tree was used to identify low-risk elderly (> or = 75 years) patients.

RESULTS

Operative mortality increased four-fold from 4.1% in patients aged less than 50 years up to 17.0% in patients aged 80 years or more. Similarly, major operative complications (stroke, prolonged ventilation, reoperation for bleeding, renal failure, and sternal infection) also increased with age, rising from 13.5% (age < 50 years) to 35.5% (age > or = 80 years). Multivariable adjustment attenuated the odds of operative mortality, but age remained a significant risk factor. After adjusting for other patient risk factors, age accounted for 13% and 10% of the explainable risk for mortality and morbidity, respectively. Among the elderly, four variables (hemodynamic instability, New York Heart Association class IV, renal failure, and concomitant coronary artery bypass grafting) were identified to distinguish levels of risk, from operative mortality rates exceeding 31% to those with 7.7% mortality.

CONCLUSIONS

Operative mortality and morbidity rise with increasing age of patients undergoing mitral valve replacement. Although this excess risk is partially a result of increased comorbid burden and other operative factors, age remains an independent powerful risk factor for operative risk for mitral valve replacement. Understanding the relationship of age with other risk factors for mitral valve replacement can help stratify risk, enabling physicians to identify lower risk patients.

Influence of age on clinical course, management and mortality of acute myocardial infarction in the Spanish population

BACKGROUND

To assess age-related differences in cardiovascular risk factors, clinical course and management of patients with acute myocardial infarction (AMI) in intensive care (ICU) or coronary care units (CCU).

METHODS

A retrospective cohort study was conducted of all AMI patients listed in the ARIAM register (Analysis of Delay in AMI), a multi-centre register in which 119 Spanish hospitals participated. The study period was from January 1995 to January 2001. A univariate analysis was carried out to evaluate differences between different age groups. Multivariate analysis was used to assess whether age difference was an independent predisposing factor for mortality and for differences in patient management.

RESULTS

17,761 patients were admitted to the ICUs/CCUs with a diagnosis of AMI. The distribution by ages was: <55 years, 3,954 patients (22.3%); 55-64 years, 3,593 (22.2%); 65-74 years, 5,924 (33.4%); 75-84 years, 3,686 (20.8%); and >84 years, 604 (3.4%) (P<0.0001); 24.6% of the patients were female, and the relative proportion of females increased with age. There were clear differences in risk factors between the different age groups, with a predominance of tobacco, cholesterol and family history of heart disease in the younger patients. The incidence of complications, including haemorrhagic complications, increased significantly with age. The older age groups had a lower rate of thrombolysis and less use of revascularisation techniques. The mortality of the above groups was 2.6, 5.4, 10.7, 17.7 and 25.8%, respectively. Age difference was an independent predictive variable for mortality and the administration of thrombolysis.

CONCLUSIONS

The distinct age groups differed in cardiovascular risk factors, management and mortality. Age is a significant independent predictive variable for mortality and for the administration of thrombolysis.

Acute type A aortic dissection in the elderly: clinical characteristics, management, and outcomes in the current era

OBJECTIVES

We sought to evaluate the clinical characteristics, management, and outcomes of elderly patients with acute type A aortic dissection.

BACKGROUND

Few data exist on the clinical manifestations and outcomes of acute type A aortic dissection in an elderly patient cohort.

METHODS

We categorized 550 patients with type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection into two age strata (<70 and >or=70 years) and compared their clinical features, management, and in-hospital events.

RESULTS

Thirty-two percent of patients with type A dissection were aged >or=70 years. Marfan syndrome was exclusively associated with dissection in the young, whereas hypertension, atherosclerosis and iatrogenic dissection predominated in older patients. Typical symptoms (abrupt onset of chest or back pain) and signs (aortic regurgitation murmur or pulse deficits) of dissection were less common among the elderly. Fewer elderly patients were managed surgically than younger patients (64% vs. 86%, p < 0.0001). Hypotension occurred more frequently (46% vs. 32%, p = 0.002) and focal neurologic deficits less frequently (18% vs. 26%, p = 0.04) among the elderly. In-hospital mortality was higher among older patients (43% vs. 28%, p = 0.0006). Logistic regression analysis identified age >or=70 years as an independent predictor of hospital death for acute type A aortic dissection (odds ratio 1.7, 95% confidence interval 1.1-2.8; p = 0.03).

CONCLUSIONS

Our study shows significant differences between older (age >or=70 years) and younger (age <70 years) patients with acute type A aortic dissection in their clinical characteristics, management, and hospital outcomes. Future research should evaluate strategies to improve outcomes in this high-risk elderly cohort.