Prodromal unstable angina in acute myocardial infarction: prognostic value of short- and long-term outcome and predictor of infarct size

Association Between Preinfarction Angina and Culprit Lesion Morphology in Patients With ST-Segment Elevation Myocardial Infarction: An Optical Coherence Tomography Study

BACKGROUND

Previous studies reported the cardiac protection effect of preinfarction angina (PIA) in patients with acute myocardial infarction (AMI). We sought to identify culprit-plaque morphology and clinical outcomes associated with PIA in patients with ST-segment elevation myocardial infarction (STEMI) using optical coherence tomography (OCT).

METHODS AND RESULTS

A total of 279 patients with STEMI between March 2017 and March 2019 who underwent intravascular OCT of the culprit lesion were prospectively included. Of them, 153 (54.8%) patients were presented with PIA. No differences were observed in clinical and angiographic data between the two groups, except STEMI onset with exertion was significantly less common in the PIA group (24.2 vs. 40.5%, p = 0.004). Patients with PIA exhibited a significantly lower incidence of plaque rupture (40.5 vs. 61.9%, p < 0.001) and lipid-rich plaques (48.4 vs. 69.0%, p = 0.001). The thin-cap fibroatheroma (TCFA) prevalence was lower in the PIA group, presenting a thicker fibrous cap thickness, although statistically significant differences were not observed (20.3 vs. 30.2%, p = 0.070; 129.1 ± 92.0 vs. 111.4 ± 78.1 μm, p = 0.088; respectively). The multivariate logistic regression analysis indicated that PIA was an independent negative predictor of plaque rupture (odds ratio: 0.44, 95% CI: 0.268-0.725, p = 0.001). No significant differences in clinical outcomes were observed besides unplanned revascularization.

CONCLUSION

Compared with the non-PIA group, STEMI patients with PIA showed a significantly lower prevalence of plaque rupture and lipid-rich plaques in culprit lesion, implying different mechanisms of STEMI attack in these two groups.

Pulseless Electrical Activity as the Initial Cardiac Arrest Rhythm: Importance of Preexisting Left Ventricular Function

Background Pulseless electrical activity (PEA) is a common initial rhythm in cardiac arrest. A substantial number of PEA arrests are caused by coronary ischemia in the setting of acute coronary occlusion, but the underlying mechanism is not well understood. We hypothesized that the initial rhythm in patients with acute coronary occlusion is more likely to be PEA than ventricular fibrillation in those with prearrest severe left ventricular dysfunction. Methods and Results We studied the initial cardiac arrest rhythm induced by acute left anterior descending coronary occlusion in swine without and with preexisting severe left ventricular dysfunction induced by prior infarcts in non-left anterior descending coronary territories. Balloon occlusion resulted in ventricular fibrillation in 18 of 34 naïve animals, occurring 23.5±9.0 minutes following occlusion, and PEA in 1 animal. However, all 18 animals with severe prearrest left ventricular dysfunction (ejection fraction 15±5%) developed PEA 1.7±1.1 minutes after occlusion. Conclusions Acute coronary ischemia in the setting of severe left ventricular dysfunction produces PEA because of acute pump failure, which occurs almost immediately after coronary occlusion. After the onset of coronary ischemia, PEA occurred significantly earlier than ventricular fibrillation (<2 minutes versus 20 minutes). These findings support the notion that patients with baseline left ventricular dysfunction and suspected coronary disease who develop PEA should be evaluated for acute coronary occlusion.

Prior angina reduces ıschemic mitral regurgitation in patients with ST-Elevation myocardial ınfarction, role of ıschemic preconditioning

Mitral regurgitation may develop due to left ventricular (LV) remodeling within 3 months following acute myocardial infarction (AMI) and is called ischemic mitral regurgitation (IMR). Ischemic preconditioning (IPC) has been reported as the most important mechanism of the association between prior angina and the favorable outcome. The aim of this study was to investigate the effect of prior angina on the development and severity of IMR at 3rd month in patients with ST elevation MI (STEMI). Fourty five (45) patients admitted with STEMI and at least mild IMR, revascularized by PCI were enrolled. According to presence of prior angina within 72 h before STEMI, patients were then divided into two groups as angina (+) (n:26; 58%) and angina (-) (n:19; 42%). All patients underwent 2D transthoracic echocardiography at 1st, 3rd days and 3rd month. IMR was evaluated by proximal isovelocity surface area (PISA) method: PISA radius (PISA-r), effective regurgitant orifice area (EROA), regurgitant volume (Rvol). LV ejection fraction (EF %) was calculated by Simpson's method. High sensitive troponin T (hs-TnT), creatine phosphokinase myocardial band (CK-MB) and N-terminal pro-brain natriuretic peptid (NTpro-BNP) levels were compared between two groups. Although PISA-r, EROA and Rvol were similar in both groups at 1st and 3rd days, all were significantly decreased (p = 0.012, p = 0.007, p = 0.011, respectively) and EF was significantly increased (p< 0 .001) in angina (+) group at 3rd month. NTpro-BNP and hs-TnT levels at 1st day and 3rd month were similar, however CK-MB level at 3rd month was found to be significantly lower in the angina (+) group (p = 0.034). At the end of the 3rd month, it was observed that the severity of IMR evaluated by PISA method was decreased and EF increased significantly in patients who defined angina within 72 h prior to STEMI, suggesting a relation with IPC.

Specific prodromal symptoms in patients with acute coronary syndrome

AIMS

Assessing the prodromal cardiac symptoms in patients with acute coronary syndrome (ACS) and compare them with healthy population.

BACKGROUND

Identifying specific prodromal cardiac symptoms can play an important role in screening people at risk.

DESIGN

A comparative study of prodromal symptoms.

METHODS

In this comparison study, an 80-item checklist of prodromal symptoms was designed and completed by 337 participants in three groups (Patient group I, Patient group II and Healthy group). All participants were studied over a period of six months (from May to October 2017). SPSS-15 software was used to analyse the data.

RESULTS

The symptoms of pain/discomfort in chest, pain/discomfort centred in the superior part of chest, pain/discomfort in the left breast and numbness or burning of both arms were the most important symptoms to predict ACS incidence in the two patient groups (odds ratio > 4 and p ≤ .05).

Pre-infarction angina is associated with improved prognosis in diabetic patients with ST-elevation myocardial infarction - data from a contemporary cohort

BACKGROUND

Pre-infarction angina (PIA) is associated with improved prognosis in patients with ST-elevation myocardial infarction (STEMI). Some studies suggest that diabetes may blunt the effect of ischaemic preconditioning. We sought to study the impact of PIA in diabetic patients with STEMI.

METHODS

Consecutive patients with STEMI who underwent primary angioplasty were included. PIA was defined as ≥1 episode of chest pain during the week preceding STEMI diagnosis. Incident major adverse cardiovascular events (MACE) were defined as the first occurrence of all-cause death, stroke or acute myocardial infarction.

RESULTS

Of the 1143 included patients, 25% were diabetic and 32% had a history of PIA. Diabetic patients with PIA had smaller infarct sizes as estimated by peak creatine kinase (CK) [1144 (500-2212) vs. 1715 (908-3309) U/L, P = 0.003] and peak troponin [3.30 (1.90-6.58) vs. 4.88 (2.50-9.58) ng/ml, P = 0.002], compared to diabetics without PIA. They also had a lower likelihood of evolving with moderate to severe reduced left ventricle ejection fraction (LVEF) (25.6%, n = 22 vs. 46.6%, n = 82, P = 0.001). In non-diabetic patients, PIA was associated with reduced peak CK [1549 (909-2909) vs. 1793 (996-3078), P = 0.0497], but not troponin (3.74 [2.23-7.11] vs. 4.56 [2.44-7.77] ng/ml, P = 0.19), and was not associated with reduced LVEF (32.0%, n = 85 vs. 37.4%, n = 207, P = 0.13). Both diabetic and non-diabetic patients with PIA had a lower likelihood of evolving with a Killip class III/VI (non-diabetic patients: 5.6% vs. 14.1%, P = 0.002; diabetic patients: 12.8% vs. 24.6%, P = 0.049). Over a median follow-up of 18.0 (12.1-25.5) months, PIA was associated with a significant reduction in the incidence of MACE [hazard ratio 0.52, 95% confidence interval (CI) 0.37-0.74, P < 0.001], irrespective of diabetes status.

CONCLUSION

PIA is an independent predictor of favourable outcomes in the setting of STEMI for both diabetic and non-diabetic patients.

Patients with coronary artery disease after acute myocardial infarction: effects of continuous enrollment in a structured Disease Management Program on adherence to guideline-recommended medication, health care expenditures, and survival

OBJECTIVE

Acute myocardial infarction (AMI) carries increased risk of mortality and excess costs. Disease Management Programs (DMPs) providing guideline-recommended care for chronic diseases seem an intuitively appealing way to enhance health outcomes for patients with chronic conditions such as AMI. The aim of the study is to compare adherence to guideline-recommended medication, health care expenditures and survival of patients enrolled and not enrolled in the German DMP for coronary artery disease (CAD) after an AMI from the perspective of a third-party payer over a follow-up period of 3 years.

METHODS

The study is based on routinely collected data from a regional statutory health insurance fund (n = 15,360). A propensity score matching with caliper method was conducted. Afterwards guideline-recommended medication, health care expenditures, and survival between patients enrolled and not enrolled in the DMP were compared with generalized linear and Cox proportional hazard models.

RESULTS

The propensity score matching resulted in 3870 pairs of AMI patients previously and continuously enrolled and not enrolled in the DMP. In the 3-year follow-up period the proportion of days covered rates for ACE-inhibitors (60.95% vs. 58.92%), anti-platelet agents (74.20% vs. 70.66%), statins (54.18% vs. 52.13%), and β-blockers (61.95% vs. 52.64%) were higher in the DMP group. Besides that, DMP participants induced lower health care expenditures per day (€58.24 vs. €72.72) and had a significantly lower risk of death (HR: 0.757).

CONCLUSION

Previous and continuous enrollment in the DMP CAD for patients after AMI is a promising strategy as it enhances guideline-recommended medication, reduces health care expenditures and the risk of death.

Relation of coronary culprit lesion morphology determined by optical coherence tomography and cardiac outcomes to preinfarction angina in patients with acute myocardial infarction

BACKGROUND

While preinfarction angina pectoris (pre-IA) is recognized as favorable effects on acute myocardial infarction (AMI), the detail has not been fully investigated. The aims of the current study were to clarify patient characteristics, lesion morphologies determined by optical coherence tomography (OCT), and cardiac outcomes related to pre-IA in patients with AMI.

METHODS

Clinical data and outcomes were compared between AMI patients with pre-IA (pre-IA group, n = 507) and without pre-IA (non-pre-IA group, n = 653). Angiography and OCT findings were analyzed in patients with pre-intervention OCT and compared between groups of pre-IA (n = 219) and non-pre-IA (n = 269).

RESULTS

ST-segment elevation myocardial infarction (61% vs. 75%, p < 0.001) and cardiogenic shock (8% vs. 14%, p = 0.001) were less prevalent in pre-IA group. Peak creatine kinase-MB levels were lower in pre-IA group (median 83 IU/mL vs. 126 IU/mL, p < 0.001). In pre-intervention coronary angiography findings, initial TIMI flow grade 0/1 (43% vs. 56%, p = 0.019) and Rentrop collateral circulation 0/1 (69% vs. 79%, p = 0.018) were less frequently observed in pre-IA than in non-pre-IA patients. In post-thrombectomy OCT images, plaque rupture (39% vs. 56%, p = 0.003) and red thrombi (42% vs. 54%, p = 0.027) were also less frequently observed in pre-IA group. Kaplan-Meier estimate survival curves showed that cardiac death at 12-months was lower in pre-IA group than in non-pre-IA group (6.9% vs. 10.1%, p = 0.036).

CONCLUSIONS

Patients with pre-IA had less severe AMI on admission, smaller infarction size, and more favorable long-term survival, which may be caused by difference of lesion morphology between patients with and without pre-IA.

Association Between Preinfarction Angina and Angiographic Findings in Non-ST-Segment Elevation Myocardial Infarction

BACKGROUND

The association between preinfarction angina and angiographic findings has not been elucidated in patients with non-ST-segment elevation myocardial infarction (NSTEMI).

HYPOTHESIS

Patients with preinfarction angina have favorable angiographic findings.

METHODS

This retrospective study analyzed 481 patients who underwent coronary angiography within 5 days of presenting NSTEMI. Preinfarction angina was defined as experiencing ≥1 chest-pain episode within 7 days prior to admission. Infarct size was measured as the peak cardiac troponin I (cTnI) level, and large myocardial infarction (MI) was defined as a peak cTnI level >85th percentile value in the study population. Infarct-related artery (IRA) patency was defined as Thrombolysis In Myocardial Infarction grade 2 or 3 flow. Clinical and angiographic characteristics and in-hospital mortality were compared between patients with and without preinfarction angina.

RESULTS

Among 481 patients, 200 (42%) had preinfarction angina. Preinfarction angina was associated with smaller infarct size, indicated by lower peak cTnI levels (P = 0.006) and lower incidence of large MI (P = 0.02), and IRA patency (P = 0.03). There was no significant difference in in-hospital mortality. On multivariate analysis, both preinfarction angina (odds ratio: 0.53, 95% confidence interval: 0.29-0.94, P = 0.03) and IRA patency (odds ratio: 0.30, 95% confidence interval: 0.17-0.52, P < 0.001) were independent negative predictors of large MI.

CONCLUSION

Our study demonstrates that preinfarction angina is a predictor of smaller infarct size and infarct-related artery patency in NSTEMI patients, suggesting that NSTEMI patients presenting without preinfarction angina are at increased risk of developing a large MI.

Time-dependent effect of preinfarction angina pectoris and intermittent claudication on mortality following myocardial infarction: A Danish nationwide cohort study

BACKGROUND

As proxies for local and remote ischemic preconditioning, we examined whether preinfarction angina pectoris and intermittent claudication influenced mortality following myocardial infarction.

METHODS

Using medical registries, we conducted a nationwide population-based cohort study of all first-time myocardial infarction patients in Denmark during 2004-2012 (n=70,458). We computed all-cause and coronary mortality rate ratios (MRRs). We categorized time between angina/claudication presentation and subsequent myocardial infarction as 0-14, 15-30, 31-90, and > 90 days. We adjusted for age, sex, coronary intervention, comorbidities, and medication use.

RESULTS

Among all myocardial infarction patients, 18.4% had prior angina and 3.8% had prior intermittent claudication. Compared to patients without prior angina, the adjusted 30-day coronary MRR was 0.85 (95% confidence interval (CI): 0.80-0.92) for stable and 0.68 (95% CI: 0.58-0.79) for unstable angina patients. The mortality reduction increased when angina presented close to myocardial infarction and was higher for unstable than for stable angina. Thus, the 30-day coronary MRR was 0.72 (95% CI: 0.51-1.02) for stable angina and 0.35 (95% CI: 0.17-0.73) for unstable angina presenting within 14 days before MI. The results were robust for all-cause mortality and in numerous subgroups, including women, diabetics, patients treated with PCI, and patients treated with and without cardioprotective drugs. Preinfarction intermittent claudication was associated with higher short- and long-term mortality compared to patients without intermittent claudication.

CONCLUSIONS

Preinfarction angina reduced 30-day mortality, particularly when unstable angina closely preceded MI. Preinfarction intermittent claudication was associated with increased short- and long-term mortality.

Prodromal angina is associated with myocardial salvage in acute ST-segment elevation myocardial infarction

AIMS

Previous studies have shown that prodromal angina (PA) occurs frequently in acute myocardial infarction (MI) patients. However, the potential benefits of PA on ischaemic myocardial damage remain unknown.

METHODS AND RESULTS

One-hundred and fifty-four patients with acute ST-segment elevation MI successfully treated with primary percutaneous coronary intervention (PPCI) were prospectively evaluated for new-onset PA in the week preceding infarction and other factors known to influence myocardial salvage. Cardiovascular magnetic resonance was performed 8 ± 3 days after MI for the assessment of area-at-risk (AAR), MI size, myocardial haemorrhage (MH), microvascular obstruction (MO), and myocardial salvage index (MSI). Patients with PA (n = 60) compared with those without PA (n = 94) showed similar AAR but significantly smaller MI size leading to larger MSI (0.53 ± 0.27 vs. 0.32 ± 0.26, P < 0.001). Additionally, patients with PA had lower incidence of MH (18 vs. 33%) and MO (22 vs. 46%) than non-PA patients (both P < 0.05). At univariate analysis, higher MSI was associated with new-onset PA, lower myocardial oxygen consumption before PPCI, shorter time-to-PPCI, and higher post-procedural TIMI flow-grade. Neither collateral circulation nor medications administered before PPCI were associated to MSI. After correction for other covariates by multivariate analysis, new-onset PA remained significantly associated with MSI (β-value: 0.352, P < 0.001).

CONCLUSION

In acute MI patients, new-onset PA is associated with higher MSI independent of others factors known to influence jeopardized myocardium, as well as with less microvascular damage.

Preinfarction angina reduces infarct size in ST-elevation myocardial infarction treated with percutaneous coronary intervention

BACKGROUND

Preinfarction angina may act as a clinical surrogate of ischemic preconditioning that may reduce infarct size and improve mortality in the setting of thrombolytic therapy for ST-elevation myocardial infarction. However, the benefits of preinfarction angina in the setting of primary percutaneous coronary intervention with stenting is inconclusive because of the greater achievement of infarct artery patency and speed of reperfusion.

METHODS AND RESULTS

To identify a homogeneous population, we performed a retrospective analysis of 1031 patients admitted with a first ST-elevation myocardial infarction with ischemic times between 1 and 6 hours who received primary percutaneous coronary intervention. We identified 245 patients who had occluded arteries on presentation, of which 79 patients had documented preinfarction angina defined as chest pain within 24 hours of infarction. Infarct size was measured as the peak creatine kinase level, a metric supported in a subgroup by late enhancement on cardiac magnetic resonance imaging. Patients with preinfarction angina (n=79) had a 50% reduction in infarct size compared with those patients without preinfarction angina (n=166) by both peak creatine kinase (1094±75 IU/L versus 2270±102 IU/L; P<0.0001) and creatine kinase area under curve (18 420±18 941 versus 36 810±21 741 IU/h per liter; P<0.0001) despite having identical ischemic times (185±8 minutes versus 181±5 minutes; P=0.67) and angiographic area at risk (24.1±1.2% versus 25.3±0.9%; P=0.43). There was an absolute 4% improvement in left ventricular ejection fraction before discharge in those patients with preinfarction angina (P<0.02).

CONCLUSIONS

The occurrence of preinfarction angina is associated with significant myocardial protection in the setting of primary percutaneous coronary intervention with stenting during ST-elevation myocardial infarction. Because preinfarction angina is relatively common, it is important that these patients be identified in clinical trials investigating therapies designed to reduce reperfusion injury and infarct size.

Pre-infarction angina and outcomes in non-ST-segment elevation myocardial infarction: data from the RICO survey

Background

The presence of pre-infarction angina (PIA) has been shown to confer cardioprotection after ST-segment elevation myocardial infarction (STEMI). However, the clinical impact of PIA in non-ST-segment elevation myocardial infarction (NSTEMI) remains to be determined.

Methods and Results

From the obseRvatoire des Infarctus de Côte d'Or (RICO) survey, 1541 consecutive patients admitted in intensive care unit with a first NSTEMI were included. Patients who experienced chest pain <7 days before the episode leading to admission were defined as having PIA and were compared with patients without PIA. Incidence of in-hospital ventricular arrhythmias (VAs), heart failure and 30-day mortality were collected. Among the 1541 patients included in the study, 693 (45%) patients presented PIA. PIA was associated with a lower creatine kinase peak, as a reflection of infarct size (231(109–520) vs. 322(148–844) IU/L, p<0.001) when compared with the group without PIA. Patients with PIA developed fewer VAs, by 3 fold (1.6% vs. 4.0%, p = 0.008) and heart failure (18.0% vs. 22.4%, p = 0.040) during the hospital stay. Overall, there was a decrease in early CV events by 26% in patients with PIA (19.2% vs. 25.9%, p = 0.002). By multivariate analysis, PIA remained independently associated with less VAs.

Conclusion

From this large contemporary prospective study, our work showed that PIA is very frequent in patients admitted for a first NSTEMI, and is associated with a better prognosis, including reduced infarct size and in hospital VAs. Accordingly, protecting the myocardium by ischemic or pharmacological conditioning not only in STEMI, but in all type of MI merits further attention.

Depressive symptoms and healthcare utilization in patients with noncardiac chest pain compared to patients with ischemic heart disease

OBJECTIVES

We compared depressive symptoms and healthcare utilization in patients admitted for noncardiac chest pain, acute myocardial infarction, and angina pectoris after hospitalization and at 1-year follow-up.

METHODS

One hundred and thirty-one patients with noncardiac chest pain, 66 with acute myocardial infarction, and 70 with angina pectoris completed a depression screening questionnaire and the Montgomery Åsberg Depression Rating Scale. Healthcare utilization data were collected from a population-based, diagnosis-related database.

RESULTS

More than 25% of respondents reported depressive symptoms, regardless of diagnosis. At follow-up, 9% had recovered, 19% were still experiencing depressive symptoms, and 13% had developed depressive symptoms. Noncardiac patients with chest pain had similar primary care contacts, but fewer hospital admissions, than patients with an acute myocardial infarction. Patients with angina pectoris and depressive symptoms used the most healthcare services.

CONCLUSIONS

Depressive symptoms were common. Patients with noncardiac chest pain used as much primary care as did patients with an acute myocardial infarction. Interventions should focus on identifying and treating depressive symptoms.

The Correlation between Infarct Size and the QRS Axis Change after Thrombolytic Therapy in ST Elevation Acute Myocardial Infarction

OBJECTIVE

Electrocardiography (ECG) may be a practical guiding tool for prognostic infarct sizing in ST elevation acute myocardial infarction (STEAMI). In this study, we sought to find a relation between the infarct size and the change in the QRS axis after thrombolytic therapy.

MATERIALS AND METHODS

Patients with STEAMI who received thrombolytic therapy were selected retrospectively. The mean QRS axes of two ECGs (before and 90 minutes after thrombolytic therapy) were calculated. Creatinine kinase MB (CKMB) was used as the marker of infarct size.

RESULTS

We did not detect any correlation between infarct size and change in the QRS axis with respect to any myocardial infarction MI localizations (p=0.80). However, in the isolated inferior MI group, there was a good correlation between CKMB and change in the QRS axis (r=-0.52 p=0.049).

CONCLUSION

The change in the QRS axis is rarely emphasized, providing a practical and promising tool for evaluating both the efficiency of the thrombolytic therapy and prognostic infarct sizing.

Impact of prodromal symptoms on prehospital delay in patients with first-time acute myocardial infarction in Korea

BACKGROUND

Information is limited concerning how affected individuals respond to early warning signs before their acute coronary event and how the presence of prodromal symptoms impacts prehospital delay.

OBJECTIVES

This study's aim was to identify the characteristics and interpretation of prodromal symptoms in patients with a first-time acute myocardial infarction (AMI) and to determine whether the presence of prodromal symptoms was predictive of prehospital delay.

SUBJECTS AND METHODS

This was a descriptive study using semistructured interview. A total of 271 hospitalized patients diagnosed as having AMI were interviewed from November 2007 to December 2008 at a university hospital in Korea. Patients were queried regarding whether they noticed a most troubling prodromal symptom prior to their acute cardiac event and how they responded to the symptom.

RESULTS

Men (53.0%) and women (54.2%) experienced prodromal symptoms. Patients who reported prodromal symptoms were more likely to be older and to have no chest pain upon hospitalization than those with no prodromes. Many patients did not generally recognize the importance of their warning symptoms; only about 40% visited a clinic in response to any prodromal symptom. Logistic regression analyses revealed that the presence of prodromal symptoms was an independent predictor affecting prehospital delay of more than 3 hours and more than 12 hours.

CONCLUSIONS

Recognizing prodromal symptoms as needing attention could be a trigger for patients to seek medical help earlier. Educational strategies should focus on improving awareness of prodromal symptoms of AMI, particularly in those with a family history or at high risk for cardiovascular disease.

Preinfarction angina prior to first myocardial infarction does not influence long-term prognosis: a retrospective study with subgroup analysis in elderly and diabetic patients

BACKGROUND AND HYPOTHESIS

Although prodromal angina occurring shortly before an acute myocardial infarction (MI) has protective effects against in-hospital complications, this effect has not been well documented after initial hospitalization, especially in older or diabetic patients. We examined whether angina 1 week before a first MI provides protection in these patients.

METHODS

A total of 290 consecutive patients, 143 elderly (>64 years of age) and 147 adults (<65 years of age), 68 of whom were diabetic (23.4%) and 222 nondiabetic (76.6%), were examined to assess the effect of preceding angina on long-term prognosis (56 months) after initial hospitalization for a first MI.

RESULTS

No significant differences were found in long-term complications after initial hospitalization in these adult and elderly patients according to whether or not they had prodromal angina (44.4% with angina vs 45.4% without in adults; 45.5% vs 58% in elderly, P < 0.2). Nor were differences found according to their diabetic status (61.5% with angina vs 72.7% without in diabetics; 37.3% vs 38.3% in nondiabetics; P = 0.4).

CONCLUSION

The occurrence of angina 1 week before a first MI does not confer long-term protection against cardiovascular complications after initial hospitalization in adult or elderly patients, whether or not they have diabetes.

Experimental hyperlipidaemia does not prevent preconditioning and it reduces ischemia-induced apoptosis

BACKGROUND

Although ischemic preconditioning (PC) is known to confer cardioprotection in healthy subjects, it is unclear whether this phenomenon exists in the presence of hyperlipidaemia. The goal of this study was to determine whether the cardioprotective effect of PC is affected by hyperlipidaemia in a guinea pig model.

METHODS

We investigated the influence of preconditioning in normo- and hyperlipidaemic animals on papillary muscle contractility and myocardial damage as expressed by the percentage of apoptotic cells. Guinea pigs were fed a normal diet or a hyperlipidaemic diet for 5 weeks. Experiments were performed on papillary muscles subjected to experimental ischemia-reperfusion with or without prior PC.

RESULTS

The dietary treatment resulted in significant changes in lipid parameters, which had not affected the functionality of the right ventricle papillary muscle, both at basal conditions and in response to ischemia-reperfusion injury. However, it was found that the hyperlipidaemic diet had an effect on ischemia-induced apoptosis. Papillary muscles of hyperlipidaemic animals with higher HDL plasma concentrations were less susceptible to ischemia-reperfusion injury.

CONCLUSIONS

This study demonstrates that hyperlipidaemia does not alter the benefits of ischemic preconditioning such as a reduction of apoptosis and preservation of myocardial contractility. Additionally, it has been shown that plasma HDL may protect cardiomyocytes against ischemia-induced apoptosis.

A comprehensive view of sex-specific issues related to cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of mortality in women. In fact, CVD is responsible for a third of all deaths of women worldwide and half of all deaths of women over 50 years of age in developing countries. The prevalence of CVD risk factor precursors is increasing in children. Retrospective analyses suggest that there are some clinically relevant differences between women and men in terms of prevalence, presentation, management and outcomes of the disease, but little is known about why CVD affects women and men differently. For instance, women with diabetes have a significantly higher CVD mortality rate than men with diabetes. Similarly, women with atrial fibrillation are at greater risk of stroke than men with atrial fibrillation. Historically, women have been underrepresented in clinical trials. The lack of good trial evidence concerning sex-specific outcomes has led to assumptions about CVD treatment in women, which in turn may have resulted in inadequate diagnoses and suboptimal management, greatly affecting outcomes. This knowledge gap may also explain why cardiovascular health in women is not improving as fast as that of men. Over the last decades, mortality rates in men have steadily declined, while those in women remained stable. It is also becoming increasingly evident that gender differences in cultural, behavioural, psychosocial and socioeconomic status are responsible, to various degrees, for the observed differences between women and men. However, the interaction between sex-and gender-related factors and CVD outcomes in women remains largely unknown.

The impact of time and day on the presentation of acute coronary syndromes

BACKGROUND

The frequency of acute myocardial infarction (AMI) peaks on Mondays and in the mornings. However, the distribution of the types of acute coronary syndromes (ACS), including unstable angina (UA), has not been systematically evaluated.

HYPOTHESIS

The distribution of the types of ACS and clinical presentations varies by time and day of admission.

METHODS

A retrospective cohort study was conducted in 1,946 consecutive nontransfer ACS admissions (1999-2004) to a tertiary-care academic center to assess presenting clinical variables in patients admitted on days versus nights (6 P.M.-6 A.M.) and weekdays versus weekends (Friday 6 P.M.-Monday 6 A.M.).

RESULTS

There were fewer ACS admissions than expected on nights and weekends (p < 0.001), but the proportion of patients with ACS presenting with ST-elevation myocardial infarction (STEMI) is 64% higher on weekends (p < 0.001) and 31% higher on nights (p = 0.022). This increased proportion with STEMI results in a greater proportion of ACS with AMI on weekends (up arrow 10%, p = 0.006) and nights (up arrow 7%, p = 0.033). Using multivariate modeling, the increase in patients with AMI on weekends was not explained by conventional risk predictors.

CONCLUSIONS

Although fewer patients with ACS presented on nights and weekends, patients at those times were more likely to have an AMI, driven largely by an increased proportion with STEMI at those times. Consideration should be given to these findings when developing clinical care paradigms, health care staffing needs, and when comparing new treatment outcomes in patients with ACS.

Residual flow to the infarct zone against lethal ventricular tachyarrhythmias during the acute phase of myocardial infarction

BACKGROUND

The benefits of residual flow to the infarct zone have been demonstrated in acute myocardial infarction (AMI), but its relation to ventricular tachyarrhythmias remains uncertain.

HYPOTHESIS

This study was undertaken to test the hypothesis that residual flow is an important determinant of lethal ventricular tachyarrhythmias (sustained ventricular tachycardia or ventricular fibrillation) during the acute phase of AMI.

METHODS

We investigated the determinants of lethal ventricular tachyarrhythmias within 24 h after the onset of symptoms in 310 consecutive patients (256 men; age 57.4 +/- 11.5 years) with AMI undergoing primary angioplasty. Patients were divided into two groups: those with (Group 1, n = 40) and those without (Group 2, n = 270) lethal ventricular tachyarrhythmias. Residual flow was defined as the presence of anterograde flow (> or = Thrombolysis in Myocardial Infarction [TIMI] 2 flow) or good angiographic collaterals (> or = grade 2) on a preintervention angiogram.

RESULTS

Univariate determinants of lethal ventricular tachyarrhythmias were cardiogenic shock, systolic blood pressure, peak level of creatine kinase, culprit artery, spontaneous reperfusion, and residual flow. In multivariate analysis, however, cardiogenic shock (odds ratio [OR] = 4.79, 95% confidence interval [CI] 1.63-14.11, p = 0.004), residual flow (OR = 0.34, 95% CI 0.14-0.81, p = 0.015), and the right coronary artery as the culprit artery (OR = 2.09,95% CI 1.03-4.22, p = 0.040) were independent determinants of these arrhythmias. In-hospital death occurred in 10 patients and was more common in Group 1 than in Group 2 (12.5% vs. 1.9%, respectively, p < 0.001).

CONCLUSION

The absence of residual flow was associated with greater risk of lethal ventricular tachyarrhythmias during the acute phase of AMI, suggesting a protective role of residual flow against these arrhythmias in AMI.

Aborted myocardial infarction in patients with ST-segment elevation

OBJECTIVES

The investigators undertook a systematic, comprehensive analysis of the therapeutic response and clinical outcomes of reperfusion therapy for acute ST-segment elevation myocardial infarction (STEMI) in 5,470 patients from the Assessment of the Safety and Efficacy of a New Thrombolytic Regimen (ASSENT)-3 trial.

BACKGROUND

Prompt effective reperfusion therapy for acute STEMI may attenuate major myocardial necrosis.

METHODS

We prospectively collected sequential electrocardiographs and clinical data. Aborted myocardial infarction (MI) was defined as maximal creatine kinase < or =2x upper limit of normal coupled with typical evolutionary electrocardiographic changes.

RESULTS

Of the patients, 727 (13.3%) had an aborted MI, with the highest frequency (25%) occurring in patients treated <1 h after symptom onset. As compared with MI patients, patients with aborted MI more often had complete ST-segment resolution at 60 min (56.3% vs. 30.2%, p < 0.001) and 180 min (61.5% vs. 53%, p < 0.001); they also had smaller infarct sizes based on QRS score at discharge (2.37 vs. 4.62, p <0.001). Mortality in aborted MI patients compared with those who had true MI was 3.9% versus 4.6% at 30-day and 7.0% versus 7.4% at 1-year. The baseline-adjusted mortality was significantly lower in patients with aborted MI (odds ratio [OR] 0.76, 95% confidence interval [CI] 0.63 to 0.92, p = 0.005 for 30-day and OR 0.70, 95% CI 0.50 to 0.98, p = 0.035 for one year). A very low-risk subset was identified with > or =70% ST-segment resolution at 60 min whose 30-day and 1-year mortality was 1.0% and 2.7%, respectively, compared with 5.9% and 9.3% in aborted MI patients with <70% ST-segment resolution at 60 min (all p < or = 0.002).

CONCLUSIONS

Prompt fibrinolytic treatment improved the likelihood of aborted MI. The subgroup with complete 60-min ST-segment resolution had the best clinical outcomes.

Is the Beneficial Effect of Preinfarction Angina Related to an Immune Response?

Immune-mediated mechanisms are thought to play a key role in the development of coronary artery disease and its thrombotic complications. Preinfarction angina has been suggested to improve left ventricular function and short-term outcomes. The purpose of the present study was to investigate the relation between the immune response and in-hospital clinical course in preinfarction angina. We prospectively evaluated 93 patients. Forty-three patients exhibited preinfarction angina within 24 hours before the onset of acute myocardial infarction (AMI) (preinfarction angina group) and 50 patients were free from preinfarction angina (sudden onset group). The incidence of complications (heart failure, recurrent angina, arrhythmia and coronary interventions) and in-hospital mortality were assessed in the two study groups. We detected some immune markers, including white blood cells, C-reactive protein, immunoglobulins, and complement. White blood cells and CRP were significantly lower in the preinfarction angina group than in the sudden onset group (P < 0.001, P < 0.005, respectively). Conversely, IgE and C(4) were significantly higher in the preinfarction angina group than in the sudden onset group (P < 0.001, P < 0.001, respectively). The incidences of heart failure and severe arrhythmias were lower in the preinfarction group than in the sudden onset group (P < 0.005, P < 0.05 respectively). The beneficial effect of preinfarction angina may be associated with an immune-inflammatory response modified by a brief ischemic episode.

Usefulness of prodromal unstable angina pectoris in predicting better survival and smaller infarct size in acute myocardial infarction (The InTIME-II Prodromal Symptoms Substudy)

Prodromal unstable angina on presentation is a significant predictor of smaller infarct size, reflected by smaller creatine kinase-MB and creatine kinase total measurements and lower 30-day, 6-month, and 5-year mortality. These findings suggest that prodromal unstable angina is an important physiologic marker that should be routinely collected for risk stratification.

The chest pain center strategy for delivering community heart attack care by shifting the paradigm of heart attack care to earlier detection and treatment

Heart attack remains the number one health problem in the United States and throughout the world. It has been that way for more than 100 years. Unless we change our course, heart attack will continue to exert its horrendous casualties, not only in the United States but also throughout the world. Our present strategy in dealing with this problem needs both leadership and a change in direction. In an effort to search "outside the box" for the solution to this problem, this symposium is a call to action that challenges us to approach the heart attack problem with a mindset bent on winning this war against heart disease, and not coexisting and accepting the problem as an inescapable fate.

Cardiac markers of acute coronary syndromes: is there a case for point-of-care testing?

OBJECTIVE

Major challenges for physicians include selection of effective tests in the time-sensitive identification and management of patients with acute coronary syndromes (ACS). We review whether cardiac marker testing performed at the point-of-care (POC) has an impact on clinical management and guidance of intervention for ACS patients.

DESIGN AND METHODS

Evidence from recently published studies and meta-analyses supports the efficacy of cardiac markers. Technologies and specifications of all currently available POC tests for monitoring cardiac markers are surveyed. Finally, a series of questions to investigate the utility of cardiac markers, and their measurement by POC tests, for clinical management and guidance of therapy for ACS patients, are addressed.

RESULTS

Cardiac troponins are clearly the best markers for the definitive detection of myocardial infarction. Compelling evidence for the utility of troponins in risk stratification and guidance of intervention for ACS patients has resulted in inclusion of cardiac markers in clinical guidelines. Rapid multi-analyte POC tests, few of which exhibit harmony with central laboratory assays, have facilitated the use of cardiac markers for clinical management and guidance of therapy.

CONCLUSIONS

Given the need to minimize vein-to-brain time, it is expected that point-of-care testing of cardiac markers will take a leading role in management of ACS patients.

Determinants and prognostic significance of spontaneous coronary recanalization in acute myocardial infarction

Spontaneous recanalization (SR) occurs after the onset of acute myocardial infarction (AMI), but its clinical significance in the reperfusion era remains uncertain. We evaluated the determinants and prognostic significance of SR in 196 consecutive patients with AMI who underwent primary angioplasty at our institution. The study population was divided into 2 groups according to the presence (group I, n = 44) or absence (group II, n = 152) of SR (Thrombolysis In Myocardial Infarction [TIMI] anterograde > or = 2 flow on the preintervention angiogram). The primary end point was the occurrence, within 6-weeks after AMI, of death, nonfatal reinfarction, and congestive heart failure. Baseline characteristics were similar between the 2 groups. Peak levels of creatine kinase were lower in group I than in group II (2,500 +/- 1,800 vs 4,000 +/- 2,900 U/L, respectively, p < 0.05). The rate of TIMI flow grade 3 after intervention was higher in group I than in group II (93.2% vs 79.6%, respectively, p < 0.05), and patients in group I had a faster corrected TIMI frame count than those in group II (22.7 +/- 12.4 vs 30.3 +/- 22.8, respectively, p < 0.05). Preinfarction angina (odds ratio [OR] 2.18, 95% confidence interval [CI] 1.10 to 4.33, p < 0.05), heavy thrombi (OR 0.10, 95% CI 0.01 to 0.74, p < 0.05), and good angiographic collaterals (OR 0.12, 95% CI 0.02 to 0.89, p < 0.05) were independent predictors of SR. Death, reinfarction, and severe arrhythmia were not different between the 2 groups. However, heart failure occurred more frequently in group II than in group I (15.1% vs 2.3%, respectively, p < 0.05). The primary end point was also significantly lower in group I than in group II (4.5% vs 18.4%, respectively, p < 0.05). In conclusion, SR in AMI is associated with faster coronary flow, smaller infarct size, and a better clinical outcome after primary angioplasty.