High-grade atrioventricular block in acute coronary syndromes: insights from the Global Registry of Acute Coronary Events.

BACKGROUND: While prior work has suggested that a high-grade atrioventricular block (HAVB) in the setting of an acute coronary syndrome (ACS) is associated with in-hospital death, limited information is available on the incidence of, and death associated with, HAVB in ACS patients receiving contemporary management. METHODS AND RESULTS: The incidence of HAVB was determined within The Global Registry of Acute Coronary Events (GRACE). The clinical characteristics, in-hospital therapies, and outcomes were compared between patients with and without HAVB. Factors associated with death in patients with HAVB were determined. A total of 59 229 patients with ACS between 1999 and 2007 were identified; 2.9% of patients had HAVB at any point during the index hospitalization; 22.7% of whom died in hospital [adjusted odds ratio (OR) = 4.2, 95% confidence interval (CI), 3.6-4.9, P < 0.001]. The association between HAVB and in-hospital death varied with type of ACS [OR: ST-segment elevation myocardial infarction (STEMI) = 3.0; non-STEMI = 6.4; unstable angina = 8.2, P for interaction < 0.001]. High-grade atrioventricular block present at the time of presentation to hospital (vs. occurring in-hospital) and early (<12 h) percutaneous coronary intervention or fibrinolysis (vs.>12 h or no intervention) were associated with improved in-hospital survival, whereas temporary pacemaker insertion was not. Patients with HAVB surviving to discharge had similar adjusted survival at 6 months compared with those without HAVB. A reduction in the rate of, but not in-hospital mortality associated with, HAVB was noted over the study period. CONCLUSION: Although the incidence of HAVB is low and decreasing, this complication continues to have a high risk of in-hospital death.

Prognostic value of myocardial circumferential strain for incident heart failure and cardiovascular events in asymptomatic individuals: the Multi-Ethnic Study of Atherosclerosis.

AIMS: Left ventricular (LV) circumferential strain (Ecc) is a sensitive index of regional myocardial function. Currently, no studies have assessed its prognostic value in general population. We sought to investigate whether Ecc has a prognostic value for predicting incident heart failure (HF) and other major cardiovascular events in asymptomatic individuals without a history of previous cardiovascular diseases. METHODS AND RESULTS: We, prospectively, assessed incident HF and atherosclerotic events during a 5.5 ± 1.3-year period in 1768 asymptomatic individuals aged 45-84 (mean age 65 years; 47% female) who underwent tagged magnetic resonance imaging for strain determination. During the follow-up period, 39 (2.2%) participants experienced incident HF and 108 (6.1%) participants had atherosclerotic cardiovascular events. Average of peak Ecc of 12-LV segments (Ecc-global) and mid-slice (Ecc-mid) was -17.0 ± 2.4 and -17.5 ± 2.7%, respectively. Participants with average absolute Ecc-mid lower than -16.9% had a higher cumulative hazard of incident HF (log-rank test, P = 0.001). In cox regression analysis, Ecc-mid predicted incident HF independent of age, diabetes status, hypertension, interim myocardial infarction, LV mass index, and LV ejection fraction (hazard ratio 1.15 per 1%, 95% CI: 1.01-1.31, P = 0.03). This relationship remained significant after adjustment for LV-end-systolic wall stress into covariates. In addition, by adding Ecc-mid to risk factors, LV ejection fraction, and the LV mass index, both the global χ(2) value (76.6 vs. 82.4, P = 0.04) and category-less net-reclassification index (P = 0.01, SE = 0.18, z = 2.53) were augmented for predicting HF. Circumferential strain was also significantly related to the composite atherosclerotic cardiovascular events, but its relationship was attenuated after introducing the LV mass index. CONCLUSION: Circumferential shortening provides robust, independent, and incremental predictive value for incident HF in asymptomatic subjects without any history of previous clinical cardiovascular disease. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT00005487.

Tissue mapping by cardiac magnetic resonance imaging for the prognostication of cardiac amyloidosis: A systematic review and meta-analysis.

BACKGROUND: Cardiac amyloidosis is increasingly recognized as a significant contributor to cardiovascular morbidity and mortality. With the emergence of novel therapies, there is a growing interest in prognostication of patients with cardiac amyloidosis using cardiac magnetic resonance imaging (CMR). In this systematic review and meta-analysis, we aimed to examine the prognostic significance of myocardial native T1 and T2, and extracellular volume (ECV). METHODS: Observational cohort studies or single arms of clinical trials were eligible. MEDLINE, EMBASE and CENTRAL were systematically searched from their respective dates of inception to January 2023. No exclusions were made based on date of publication, study outcomes, or study language. The study populations composed of adult patients (≥18 years old) with amyloid cardiomyopathy. All studies included the use of CMR with and without intravenous gadolinium contrast administration to assess myocardial native T1 mapping, T2 mapping, and ECV in association with the pre-specified primary outcome of all-cause mortality. Data were extracted from eligible primary studies by two independent reviewers and pooled via the inverse variance method using random effects models for meta-analysis. RESULTS: A total of 3852 citations were reviewed. A final nine studies including a total of 955 patients (mean age 65 ± 10 years old, 32% female, mean left ventricular ejection fraction (LVEF) 59 ± 12% and 24% had NYHA class III or IV symptoms) with cardiac amyloidosis [light chain amyloidosis (AL) 50%, transthyretin amyloidosis (ATTR) 49%, other 1%] were eligible for inclusion and suitable for data extraction. All included studies were single centered (seven with 1.5 T MRI scanners, two with 3.0 T MRI scanners) and non-randomized in design, with follow-up spanning from 8 to 64 months (median follow-up = 25 months); 320 patients died during follow-up, rendering a weighted mortality rate of 33% across studies. Compared with patients with AL amyloid, patients with ATTR amyloid had significantly higher mean left ventricular mass index (LVMi) (102 ± 34 g/m2 vs 127 ± 37 g/m2, p = 0.02). N-terminal pro-brain natriuretic peptide (NT-proBNP), troponin T levels, mean native T1 values, ECV and T2 values did not differ between patients with ATTR amyloid and AL amyloid (all p > 0.25). Overall, the hazard ratios for mortality were 1.33 (95% CI = [1.10, 1.60]; p = 0.003; I2 = 29%) for every 60 ms higher T1 time, 1.16 (95% CI = [1.09, 1.23], p < 0.0001; I2 = 76%) for every 3% higher ECV, and 5.23 (95% CI = [2.27, 12.02]; p < 0.0001; I2 = 0%) for myocardial-to-skeletal T2 ratio below the mean (vs above the mean). CONCLUSION: Higher native T1 time and ECV, and lower myocardial to skeletal T2 ratio, on CMR are associated with worse mortality in patients with cardiac amyloidosis. Therefore, tissue mapping using CMR may offer a useful non-invasive technique to monitor disease progression and determine prognosis in patients with cardiac amyloidosis.

Prognostic significance of presenting blood pressure in non-ST-segment elevation acute coronary syndrome in relation to prior history of hypertension.

BACKGROUND: Hypertension is a well-established risk factor for cardiovascular disease, whereas low systolic blood pressure (SBP) is a powerful adverse prognosticator in acute coronary syndrome. However, it is unclear whether the prognostic significance of low SBP differs in patients with versus without prior history of hypertension. We sought to investigate the relationships between presenting SBP, prior hypertension, antihypertensive medication use, and outcomes in non-ST-segment elevation acute coronary syndrome (NSTEACS). METHODS: Using data from GRACE/GRACE(2) and CANRACE, we stratified 10,337 patients with NSTEACS from 1999 to 2008 into 2 groups: those with and those without prior diagnosis of hypertension. We performed multivariable logistic regression analysis to assess the prognostic significance of prior hypertension on in-hospital mortality and tested for the interactions between prior hypertension, antihypertensive medication use, and presenting SBP. RESULTS: Compared with patients without prior hypertension (n = 3,732), those with prior hypertension (n = 6,605) were older; more likely to be female; and more frequently had diabetes, previous myocardial infarction, heart failure, renal insufficiency, and higher Killip class and GRACE risk scores on presentation. Patients with prior hypertension were more likely to be on antihypertensive medications before admission, to present with higher SBP, and to have heart failure or cardiogenic shock in hospital (6.0% vs 10.1%; P < .001). In-hospital mortality was higher among patients presenting with lower SBP but did not differ between the groups with and without prior hypertension. In multivariable analysis, neither prior hypertension (adjusted odds ratio = 1.15, 95% CI 0.78-1.70, P = .48) nor the number of antihypertensive medications used (P for trend = .84) was independently associated with in-hospital mortality. In contrast, SBP was a strong independent predictor of in-hospital mortality (adjusted odds ratio = 1.21 per 10 mm Hg lower, 1.15-1.27, P < .001). There was no significant interaction between SBP and prior hypertension (P for interaction = .62) or pre-admission antihypertensive medication use (P for interaction = .46) with respect to in-hospital mortality. CONCLUSION: Low SBP on presentation, but not prior hypertension, was independently associated with in-hospital mortality in NSTEACS. The powerful prognostic value of SBP is similar regardless of a history of hypertension or pre-admission antihypertensive medication use.

Comparative prognostic value of T-wave inversion and ST-segment depression on the admission electrocardiogram in non-ST-segment elevation acute coronary syndromes.

BACKGROUND: ST-segment depression (STD) is predictive of adverse outcomes in non-ST-segment elevation acute coronary syndromes (NSTE-ACS), but there are conflicting data on the incremental prognostic value of T-wave inversions (TWIs) on the admission electrocardiogram. METHODS: Admission electrocardiograms of 7,343 patients with NSTE-ACS from the Global Registry of Acute Coronary Events (GRACE) and ACS I registry were independently analyzed at a core laboratory and stratified by TWI and STD status. We performed multivariable analyses to determine the independent prognostic significance of TWI and tested for interaction between TWI and STD for adverse outcomes. RESULTS: Patients with TWI and/or STD had a higher prevalence of cardiovascular risk factors, higher Killip class, and higher GRACE risk scores. Among the 2,708 patients with available angiographic data, rates of 3-vessel or left main disease were similar between patients with TWI and those without TWI/STD. After adjusting for other established prognosticators, TWI did not independently predict in-hospital (adjusted odds ratio 1.03, 95% CI 0.75-1.42, P = .85) or 6-month mortality (adjusted odds ratio 1.02, 95% CI 0.80-1.30, P = .88); STD remained a strong independent predictor. There was no interaction between TWI and STD for these outcomes. No contiguous lead groups or cumulative number of leads with TWI provided independent prognostic information. CONCLUSIONS: TWI is associated with other high-risk clinical features but is not an independent predictor of adverse short- and long-term mortality in NSTE-ACS. T-wave inversion does not provide additional prognostication beyond the GRACE risk model, and its concomitant presence does not alter the prognostic value of STD.

Canada Acute Coronary Syndrome Risk Score: a new risk score for early prognostication in acute coronary syndromes.

BACKGROUND: Despite the availability of several acute coronary syndrome (ACS) prognostic risk scores, there is no appropriate score for early-risk stratification at the time of the first medical contact with patients with ACS. The primary objective of this study is to develop a simple risk score that can be used for early-risk stratification of patients with ACS. METHODS: We derived the risk score from the Acute Myocardial Infarction in Quebec and Canada ACS-1 registries and validated the risk score in 4 other large data sets of patients with ACS (Canada ACS-2 registry, Canada-GRACE, EFFECT-1, and the FAST-MI registries). The final risk score is named the Canada Acute Coronary Syndrome Risk Score (C-ACS) and ranged from 0 to 4, with 1 point assigned for the presence of each of these variables: age ≥75 years, Killip >1, systolic blood pressure <100 mm Hg, and heart rate >100 beats/min. The primary end points were short-term (inhospital or 30-day) and long-term (1- or 5-year) all-cause mortality. RESULTS: The C-ACS has good predictive values for short- and long-term mortality of patients with ST-segment elevation myocardial infarction and non-ST-segment elevation ACS. The negative predictive value of a C-ACS score ≥1 is excellent at ≥98% (95% CI 0.97-0.99) for short-term mortality and ≥93% (95% CI 0.91-0.96) for long-term mortality. In other words, a C-ACS score of 0 can potentially identify correctly ≥97% short-term survivors and ≥91% long-term survivors. CONCLUSION: The C-ACS risk score permits rapid stratification of patients with ACS. Because this risk score is simple and easy to memorize and calculate, it can be rapidly applied by health care professionals without advanced medical training.

Pre-hospital cardiac arrest in acute coronary syndromes: insights from the global registry of acute coronary events and the canadian registry of acute coronary events.

OBJECTIVES: Cardiac arrest in acute coronary syndromes (ACS) is associated with high morbidity and mortality. We examined the clinical characteristics, contemporary management patterns and outcomes of ACS patients with pre-hospital cardiac arrest. METHODS: The Global Registry of Acute Coronary Events and the Canadian Registry of Acute Coronary Events enrolled 14,010 ACS patients in 1999-2008. We compared the clinical characteristics, in-hospital treatment and outcomes between patients with and without pre-hospital cardiac arrest. RESULTS: Overall, 206 (1.4%) patients had cardiac arrest prior to hospital presentation. ACS patients with pre-hospital cardiac arrest were less frequently treated with aspirin, ß-blocker, angiotensin-converting enzyme inhibitors, and statins within the first 24 h of presentation, but the use of cardiac procedures was similar compared to the group without cardiac arrest. Patients with pre-hospital cardiac arrest had significantly higher rates of in-hospital adverse events. Factors independently associated with pre-hospital cardiac arrest included male gender, current smoker status, tachycardia, higher Killip class and ST-segment deviation. CONCLUSION: ACS patients with pre-hospital cardiac arrest continue to have more in-hospital complications and higher mortality. Their use of evidence-based medical therapies was lower but the use of cardiac procedures was similar compared to the group without cardiac arrest. Better utilization of evidence-based therapies in these patients may translate into improved outcomes.

Bridging the gender gap: Insights from a contemporary analysis of sex-related differences in the treatment and outcomes of patients with acute coronary syndromes.

BACKGROUND: The question of whether gender-related disparities still exist in the treatment and outcomes of patients presenting with acute coronary syndromes (ACS) remains controversial. Using data from 4 registries spanning a decade, we sought to determine whether sex-related differences have persisted over time and to examine the treating physician's rationale for adopting a conservative management strategy in women compared with men. METHODS: From 1999 to 2008, 14,196 Canadian patients with non-ST-segment elevation ACS were recruited into the Acute Coronary Syndrome I (ACSI), ACSII, Global Registry of Acute Coronary Events (GRACE/GRACE(2)), and Canadian Registry of Acute Coronary Events (CANRACE) prospective multicenter registries. RESULTS: Women in the study population were found to be significantly older than men and were more likely to have a history of heart failure, diabetes, or hypertension. Fewer women were treated with thienopyridines, heparin, and glycoprotein IIb/IIIa inhibitors compared with men in GRACE and CANRACE. Female gender was independently associated with a lower in-hospital use of coronary angiography (adjusted odds ratio 0.76, 95% CI 0.69-0.84, P < .001) and higher in-hospital mortality (adjusted odds ratio 1.26, 95% CI 1.02-1.56, P = .036), irrespective of age (P for interaction =.76). Underestimation of patient risk was the most common reason for not pursuing an invasive strategy in both men and women. CONCLUSIONS: Despite temporal increases in the use of invasive cardiac procedures, women with ACS are still more likely to be treated conservatively, which may be due to underestimation of patient risk. Furthermore, they have worse in-hospital outcomes. Greater awareness of this paradox may assist in bridging the gap between current guidelines and management practices.

Efficacy of early invasive management post-fibrinolysis in men versus women with ST-elevation myocardial infarction: a subgroup analysis from Trial of Routine Angioplasty and Stenting after Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI).

BACKGROUND: The TRANSFER-AMI study demonstrated that early routine percutaneous coronary intervention post-fibrinolysis (pharmacoinvasive strategy) is superior to conservative management for ST-elevation myocardial infarction. However, it is not clear whether treatment efficacy differs between men and women. METHODS: In this pre-specified subgroup analysis, we compared the efficacy of a pharmacoinvasive strategy in men versus women with acute ST-elevation myocardial infarction who were randomized to a pharmacoinvasive versus standard management following fibrinolysis. The primary end point was a composite of death, recurrent myocardial infarction, recurrent ischemia, heart failure and shock at 30 days. We tested for treatment heterogeneity between men and women using the Breslow-Day test. We also performed multivariable analysis adjusting for GRACE risk score and its interaction with treatment assignment, and evaluated for death/recurrent myocardial reinfarction as a secondary outcome. RESULTS: Of the 1059 patients, 843 were men and 216 were women. Compared to men, women were older, had worse Killip class, higher GRACE risk score, and higher rates of death and death/myocardial reinfarction at 30 days. The primary end point did not differ significantly between men and women (13.4% vs 16.7%, P = .22). Compared to standard treatment, a pharmacoinvasive strategy was associated with a lower rate of the primary end point in men (17.5% vs 9.4%, respectively, P < .001), but not in women (16.2% vs 17.1%, P = .86). There was a trend toward an interaction between treatment assignment and sex for the composite primary end point (P = .06). After adjustment for the significant interaction between GRACE risk score and treatment (P < .001), there was no significant interaction between sex and treatment for all the end points (all P > .40). CONCLUSION: The borderline heterogeneity in treatment efficacy of a pharmacoinvasive strategy in men versus women was no longer evident after adjustment for the difference in baseline risk. This suggests that sex per se was not an important determinant of the efficacy of a pharmacoinvasive strategy. Owing to the small number of women in this trial, further study in this area is needed.

High-sensitivity C-reactive protein as an independent predictor of progressive myocardial functional deterioration: the multiethnic study of atherosclerosis.

BACKGROUND: Systemic inflammation has been linked to the development of heart failure in population studies including Multi-Ethnic Study of Atherosclerosis (MESA), but little evidence exists regarding potential mechanism of this relationship. In this study, we used longitudinal magnetic resonance imaging follow-up analysis to examine whether C-reactive protein (CRP) levels relate to progressive myocardial functional deterioration as a potential mechanism of incident heart failure. METHODS: Regional myocardial functional data from MESA participants who had baseline CRP measurement and also underwent tagged cardiac magnetic resonance imaging both at baseline and at 5-year follow-up were analyzed. Left ventricular midwall and midslice peak circumferential strain (Ecc), of which a more negative value denotes stronger regional myocardial function, was measured. Circumferential strain change was calculated as the difference between baseline and follow-up Ecc. RESULTS: During the follow-up period, participants (n = 785) with elevated CRP experienced a decrease in strain, independent of age, gender, and ethnicity (B = 0.081, ∆Ecc change per 1 mg/L CRP change, 95% CI 0.036-0.126, P < .001, model 1) and, additionally, beyond systolic blood pressure, heart rate, diabetes, smoking status, body mass index, current medication, and glomerular filtration rate (B = 0.099, 0.052-0.145, P < .001, model 2). The relationship remained statistically significant after further adjustment for left ventricular mass, coronary calcium score, and interim clinical coronary events (B = 0.098, 0.049-0.147, P < .001, model 3). CONCLUSION: Higher CRP levels are related to progressive myocardial functional deterioration independent of subclinical atherosclerosis and clinical coronary events in asymptomatic individuals without previous history of heart disease.

Factors influencing underutilization of evidence-based therapies in women.

Aims Previous studies have reported differences in the use of cardiovascular medications for acute coronary syndromes (ACSs) according to the sex of the patient. We analysed which clinical factors are associated with underutilization of evidence-based therapies in women. Methods and results From the Canadian Registry of ACS I and II, 6558 patients (4471 men and 2087 women) with a final diagnosis of ACS were selected for the current analysis. Covariates were chosen using the approach described by Blackstone. The final selected model included 23 patient clinical variables. Women were less likely than men to receive beta-blockers (75.76 vs. 79.24%; P < 0.01), lipid-modifying agents (56.37 vs. 65.44%; P < 0.0001), and angiotensin-converting enzyme (ACE)-inhibitors (55.52 vs. 59.99%; P < 0.01). Female sex and clinical decision not to investigate with cardiac catheterization were the strongest independent predictors for not receiving lipid-modifying agents and ACE-inhibitors. Age, Killip class 2, and Killip class 3/4 were significant independent predictors of underutilization of beta-blocker use. Women were older (69 ± 12 vs. 64 ± 12; P < 0.01) with a higher prevalence of Killip class ≥ 2 (19.95 vs. 15.54%; P < 0.068), and they were less likely to be referred for cardiac catheterization (41.9 vs. 49.6 %; P < 0.001). Conclusions The current findings demonstrate that underutilization of evidence-based therapies in women with ACS compared with men is associated with multiple factors related to the patient (age), the consequences of the disease (congestive heart failure), and the physician's assessment of patient risk (decision to catheterize). Female gender remains associated with underutilization of lipid-modifying agents and ACE-inhibitors despite adjustment for these confounders.

Relationship between risk stratification at admission and treatment effects of early invasive management following fibrinolysis: insights from the Trial of Routine ANgioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI).

AIMS: We sought to determine the effectiveness of early routine percutaneous coronary intervention (PCI) post-fibrinolysis for ST-elevation myocardial infarction (STEMI) in relation to baseline risk status. METHODS AND RESULTS: In this post hoc subgroup analysis of Trial of Routine Angioplasty and Stenting after Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI), we stratified 1059 STEMI patients receiving tenecteplase into low-intermediate [Global Registry of Acute Coronary Events (GRACE) risk score<155; n=889] vs. high-risk (GRACE risk score ≥155; n=170) groups, based on the GRACE risk score for in-hospital mortality. There was a significant interaction between treatment assignment and risk status for the composite endpoint of death/re-MI at 30 days (P for interaction<0.001). Compared with the standard treatment, pharmacoinvasive therapy (early routine PCI) was associated with a lower rate of death/re-MI at 30 days in the low-intermediate risk stratum (8.1 vs. 2.9%, P<0.001), but a higher rate of death/re-MI in the high-risk group (13.8 vs. 27.8%, P=0.025). We found similar heterogeneity in the treatment effects on 30-day mortality and death/re-MI at 1 year (P for interaction=0.008 and 0.001, respectively), when the GRACE risk score was analysed as a continuous variable (P for interaction<0.001) and when patients were stratified by the Thrombolysis In Myocardial Infarction (TIMI) risk score (P for interaction=0.001). CONCLUSION: We observed a strong heterogeneity in the treatment effects of a pharmacoinvasive strategy after fibrinolysis for STEMI, which is associated with improved outcomes only among patients with a low-intermediate GRACE risk score. Conversely, the early invasive strategy is associated with worse outcomes in high-risk patients. These novel findings should be considered exploratory only and require confirmation in other trials and meta-analyses. CLINICAL TRIAL REGISTRATION INFORMATION: http://www.clinicaltrials.gov/ct2/show/NCT00164190 ClinicalTrials.gov number, NCT00164190.

Temporal changes in the management and outcome of Canadian diabetic patients hospitalized for non-ST-elevation acute coronary syndromes.

BACKGROUND: There are limited data on the contemporary management and outcomes of non-ST-elevation acute coronary syndrome (NSTE-ACS) patients with diabetes in the "real world." We sought to evaluate (1) the temporal changes in the medical and invasive management and (2) in-hospital outcome of NSTE-ACS patients with and without diabetes. METHODS: We included Canadian patients hospitalized for NSTE-ACS enrolled in 4 consecutive, prospective, multicenter registries: Canadian ACS-I (n = 3259; 1999-2001), ACS-II (n = 1,956; 2002-2003), Global Registry of Acute Coronary Events (GRACE/GRACE2 [n = 7,561; 2004-2007]) and Canadian Registry of Acute Coronary Events (n = 1,326; 2008). Participants were stratified by the presence or absence of preexisting diabetes on admission. Temporal changes in patient management and outcomes were evaluated across the 4 registries. Multivariable analyses were performed to determine the independent prognostic significance of diabetes. RESULTS: Of the 14,102 NSTE-ACS patients, 4,046 (28.7%) had previously diagnosed diabetes. Patients with diabetes were older; were more likely to have prior cardiac history including myocardial infarction, revascularization, and heart failure; and had worse Killip class and higher GRACE risk score (all P < .001). Over time, there were significant increases in the use of in-hospital coronary angiography and revascularization. However, diabetic patients were less likely to undergo coronary angiography (52.5% vs 57%, P < .001) or revascularization (28.4% vs 33.4%, P < .001). The underuse of invasive procedures in diabetic patients was seen in all registries and was persistent over time. Overall, compared with the group without diabetes, diabetic patients had higher unadjusted rates of in-hospital mortality (3.0% vs 1.6%, P < .001). In multivariable analysis adjusting for components of the GRACE risk score, diabetes remained an independent predictor of in-hospital death (adjusted odds ratio 1.66, 95% CI 1.30-2.11, P < .001). CONCLUSIONS: Over the last decade, NSTE-ACS patients with diabetes continue to be treated more conservatively, despite evidence that they would derive similar or even greater benefits from aggressive treatment. This underutilization of evidence-based therapies among diabetic patients with NSTE-ACS in the "real world" may partly explain their worse outcome.

Prognostic significance of electrocardiographic-determined left ventricular hypertrophy and associated ST-segment depression in patients with non-ST-elevation acute coronary syndromes.

BACKGROUND: Left ventricular hypertrophy (LVH) is frequently associated with ST depression (STD) on the electrocardiogram (ECG), a so-called strain pattern. Although STD is a well-established adverse prognosticator in non-ST-elevation acute coronary syndrome (NSTE-ACS), the relative prognostic importance of LVH and associated STD has not been elucidated. METHODS: A total of 7,761 patients with NSTE-ACS in the Global Registry of Acute Coronary Events (GRACE) and ACS-I registries had admission ECGs analyzed at a core laboratory. Left ventricular hypertrophy (determined by Sokolow-Lyon and/or Casale criteria) was observed in 296 (3.8%) patients. We examined the independent association between LVH (determined by the admission ECG) and outcomes in relation to STD. RESULTS: Patients with LVH were older, had more comorbidities and STD, and presented with a higher Killip class. They were less likely to undergo cardiac catheterization (43.1% vs 51.2%, P = .006) and percutaneous coronary intervention (18.3% vs 24.6%, P = .014). Patients with LVH had higher unadjusted mortality at 6 months (10.5% vs 7.1%, P = .038), but similar rates of in-hospital mortality (4.1% vs 3.4%, P = .54) and reinfarction (7.1% vs 7.6%, P = .75). Patients with LVH were more likely to have heart failure in-hospital (21.8% vs 11.8%, P < .001). Among LVH patients, degree of quantitative STD did not predict higher short- or long-term mortality, but was associated with in-hospital heart failure. Multivariable analysis adjusting for other clinical prognosticators of the GRACE risk models revealed that LVH was not a significant independent predictor of in-hospital mortality (adjusted odds ratio = 0.75, 95% CI 0.40-1.41, P = .37) or 6-month mortality (adjusted odds ratio = 0.83, 95% CI 0.52-1.35, P = .44). In contrast, STD remained a strong independent predictor of adverse outcomes. There was no significant interaction between STD and LVH. CONCLUSIONS: Across the broad spectrum of NSTE-ACS, LVH is associated with adverse prognostic factors including STD. Electrocardiographic-determined LVH provides no significant additional prognostic utility beyond comprehensive risk assessment using the GRACE risk score. The adverse prognosis associated with LVH in NSTE-ACS may be attributable to other prognosticators such as STD.

Has the ClOpidogrel and Metoprolol in Myocardial Infarction Trial (COMMIT) of early ß-blocker use in acute coronary syndromes impacted on clinical practice in Canada? Insights from the Global Registry of Acute Coronary Events (GRACE).

BACKGROUND: The COMMIT/CCS-2 trial, published in 2005, demonstrated no net benefit of early ß-blocker (BB) therapy in acute coronary syndromes (ACS). We sought to assess the short-term impact of this landmark trial by comparing the use of early BB therapy in patients with a broad spectrum of ACS before and after 2005. METHODS: Using data from the Global Registry of Acute Coronary Events and Canadian Registry of Acute Coronary Events, we compared the rates of BB use within the first 24 hours of presentation in the periods 1999 to 2005 and 2006 to 2008, after stratifying patients by the type of ACS (ST-segment elevation myocardial infarction [STEMI] and non-ST-segment elevation ACS [NSTEACS]) and clinical presentation. RESULTS: Of the 14,231 patients with ACS, 77.7% received BB therapy within 24 hours of presentation (78.5% and 77.4% in the STEMI and NSTEACS groups, respectively). The early use of BB declined in the STEMI group (80.3% to 76.7%, P = .005) but increased in the NSTEACS group (75.4% to 78.9%, P < .001) after 2005. Long-term BB use, higher systolic blood pressure, and higher heart rate were independent predictors of early BB use. Conversely, patients who were female, older, Killip class >1, and had cardiac arrest at presentation were less likely to receive early BB. Multivariable analysis showed a trend toward lower use of BB among patients with STEMI (adjusted odds ratio 0.76, 95% CI 0.57-1.00, P = .055) and a trend toward more frequent BB use among patients with NSTEACS (adjusted odds ratio 1.22, 95% CI 0.96-1.55, P = .11) after 2005. The temporal trends in the early use of BB differed between patients with STEMI and patients with NSTEACS (P for interaction with period <.001). CONCLUSIONS: Most patients with STEMI or NSTEACS were treated with early BB therapy. In accordance with the COMMMIT/CCS-2 trial, patients with lower systolic blood pressure and higher Killip class in the "real world" less frequently received early BB therapy. Since the publication of COMMIT/CCS-2, there has been no significant change in the use of BB in patients with STEMI or NSTEACS after controlling for their clinical characteristics.

Relationship of interleukin-6 with regional and global left-ventricular function in asymptomatic individuals without clinical cardiovascular disease: insights from the Multi-Ethnic Study of Atherosclerosis.

AIMS: We sought to examine the relationship between circulating interleukin-6 (IL-6) level and regional left-ventricular (LV) function among apparently healthy individuals free of cardiovascular disease. METHODS AND RESULTS: Using magnetic resonance myocardial tagging, we determined peak systolic circumferential strain (Ecc) as a measure of regional systolic function in 894 asymptomatic participants in the Multi-Ethnic Study of Atherosclerosis. Ecc was analysed by harmonic phase imaging separately in the LV anterior wall, septum, lateral wall, and inferior wall. Global Ecc was calculated as the average of Ecc in all myocardial segments. We performed multivariable linear regression to evaluate the independent associations between log IL-6 and Ecc, after adjusting for demographic features, cardiovascular risk factors, and markers of subclinical atherosclerosis. The inverse relationships between IL-6 and absolute Ecc were similar in both genders. In multivariable analysis, higher IL-6 level was independently associated with reduced systolic function (less negative Ecc) in the septum [regression coefficient = 1.03 per unit higher log IL-6, 95% confidence interval (CI) 0.26-1.79, P = 0.008] and inferior wall (regression coefficient = 1.65, 95% CI 0.74-2.56, P < 0.001), but not in the anterior wall (P = 0.27) or lateral wall (P = 0.52). Overall, there was an independent inverse association between IL-6 and global Ecc (regression coefficient = 0.94, 95% CI 0.37-1.51, P = 0.001). Compared with C-reactive protein, higher IL-6 level demonstrates a stronger independent association with reduced regional systolic function. CONCLUSION: In asymptomatic men and women without documented cardiovascular disease, there is a strong, independent, inverse relationship between IL-6 and regional LV systolic function. These findings suggest that IL-6 may underlie the pathogenetic link between inflammation, LV dysfunction and incipient heart failure. The observed variable relationships between IL-6 and systolic function across different LV regions warrant further investigations.

Prognostic utility of quantifying evolutionary ST-segment depression on early follow-up electrocardiogram in patients with non-ST-segment elevation acute coronary syndromes.

AIMS: Although ST-segment depression (STD) on the admission electrocardiogram (ECG) confers adverse prognosis in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS), the implications of STD on follow-up ECG remain uncertain. We determined the prognostic significance of STD on follow-up ECG performed within 12-24 h of admission and whether its quantitative evaluation can further refine risk stratification. METHODS AND RESULTS: The admission and follow-up ECGs of 3877 patients in the SYNERGY trial were analysed for the presence (>or=1 mm) and extent (maximum magnitude on any single lead) of STD. Of the 1110 patients presenting with STD on admission, 534 (48.1%) with persistent STD at follow-up had higher mortality at 30 days (7.1 vs. 3.6%, P = 0.01) and 6 months (10.7 vs. 5.2%, P = 0.001) than those with normalized STD. Among 2767 patients without STD on admission, 174 (6.3%) developed new STD on follow-up ECG and experienced increased mortality compared with those without such interval change (30 days: 4.0 vs. 1.7%, P = 0.035; 6 months: 8.0 vs. 3.3%, P = 0.001). After adjustment for established clinical prognosticators and the extent of STD on admission, every 1 mm increment of STD on the follow-up ECG independently predicted a graded increase in 30-day mortality [hazards ratio (HR) = 1.60, 95% confidence interval (CI) = 1.29-1.98, P < 0.0001], and death/myocardial infarction at 30 days (HR = 1.19, 95% CI = 1.03-1.36, P = 0.017) and 6 months (HR = 1.17, 95% CI = 1.03-1.32, P = 0.016). CONCLUSION: The magnitude of STD on a routine 12-24 h follow-up ECG provides incremental prognostic information beyond established clinical prognosticators and the extent of STD on admission. Incorporating a follow-up ECG and its quantitative evaluation for STD may further refine risk stratification of patients with NSTE-ACS.

QRS prolongation in patients with acute coronary syndromes.

BACKGROUND: QRS prolongation with or without bundle branch block (BBB) has been associated with adverse outcome in myocardial infarction; we examined the relationship between QRS duration and outcome in a broad spectrum of patients with acute coronary syndrome (ACS). METHOD AND RESULTS: Core laboratory evaluation of the presenting electrocardiogram in Canadian ACS Registry patients (n = 5,003) showed 4,289 (85.7%) had QRS <120 milliseconds, 202 (4.0%) patients had QRS > or =120 milliseconds without BBB, 262 (5.2%) had left BBB (LBBB), and 250 (5.0%) had right BBB. Compared to patients with QRS <120 milliseconds, patients with QRS > or =120 milliseconds without BBB had higher in-hospital (3.5% vs 1.9%, odds ratio [OR] 1.87, 95% CI 0.85-4.09, P = .12) and 1-year mortality (14.9% vs 7.7%, OR 2.10, 95% CI 1.38-3.18, P = .001). In-hospital and 1-year mortality was significantly higher in patients with BBB (eg, LBBB compared with QRS <120 milliseconds) (5.0% vs 1.9%, OR 2.71, 95% CI 1.49-4.94, P = .001, and 23.8% vs 7.7%, OR 3.74, 95% CI 2.72-5.13, P < .001). Analyzed as a continuous variable and after adjustment for validated prognosticators, QRS duration was an independent predictor of 1-year death (OR 1.11, 95% CI 1.06-1.16, P < .001) and death/myocardial infarction (OR 1.06, 95% CI 1.02-1.11, P = .003). However, when using clinically applicable QRS duration evaluation, only LBBB was an independent predictor of 1-year mortality (OR 1.93, 95% CI 1.28-2.90, P = .002). CONCLUSIONS: In patients presenting with a broad spectrum of suspected ACS, QRS prolongation-particularly in the setting of LBBB-is an independent predictor of in-hospital and 1-year mortality.

Management patterns of non-ST segment elevation acute coronary syndromes in relation to prior coronary revascularization.

BACKGROUND: Contemporary guidelines support an early invasive strategy for non-ST elevation acute coronary syndrome (NSTE-ACS) patients who had prior coronary revascularization. However, little is known about the management pattern of these patients in "real world." METHODS: We analyzed 3 consecutive Canadian registries (ACS I, ACS II, and Global Registry of Acute Coronary Events [GRACE]/expanded-GRACE) that recruited 12,483 NSTE-ACS patients from June 1999 to December 2007. We stratified the study population according to prior coronary revascularization status into 4 groups and compared their clinical characteristics, in-hospital use of medications, and cardiac procedures. RESULTS: Of the 12,483 NSTE-ACS patients, 71.2% had no prior revascularization, 14.2% had percutaneous coronary intervention (PCI) only, 9.5% had coronary artery bypass graft surgery (CABG) only, and 5% had both PCI and CABG. Compared to their counterparts without prior revascularization, patients with previous PCI and/or CABG were more likely to be male, to have diabetes, myocardial infarction, and heart failure but less likely to have ST-segment deviation or positive cardiac biomarker on presentation. Early use of evidence-based medications was higher among patients with previous PCI only and lower among patients with previous CABG only. After adjusting for possible confounders including GRACE risk score, prior PCI was independently associated with in-hospital use of cardiac catheterization (adjusted odds ratio [OR] 1.18, 95% CI 1.04-1.34, P = .008). In contrast, previous CABG was an independent negative predictor (adjusted OR .77, 95% CI 0.68-0.87, P < .001). There was no significant interaction (P = .93) between previous PCI and CABG. CONCLUSIONS: The NSTE-ACS patients with previous PCI were more likely to be treated invasively. Conversely, patients with prior CABG less frequently received invasive therapy. Future studies should determine the appropriateness of this treatment discrepancy.

Temporal trend of in-hospital major bleeding among patients with non ST-elevation acute coronary syndromes.

BACKGROUND: Although randomized controlled trials support the use of intensive medical and invasive therapies for non-ST segment elevation acute coronary syndromes (NSTE-ACS), major bleeding is a serious treatment complication. We sought to determine the temporal trend of in-hospital major bleeding among patients with NSTE-ACS, in relation to the evolving management pattern. METHODS: We identified 14 111 NSTE-ACS patients enrolled in 4 successive, prospective, multicenter registries (ACS I, 1999-2001; ACS II, 2002-2003; GRACE, 2004-2007; and CANRACE, 2008) in Canada between 1999 and 2008. We collected data on patient characteristics, use of cardiac medications and procedures on standardized case report forms. In all registries, major bleeding was defined a priori as life threatening or fatal bleeding, bleeding requiring transfusion of ≥2 U of packed red cells, or resulting in an absolute decrease in hemoglobin of >30g/L. RESULTS: A total of 14 111 patients had a final diagnosis of NSTE-ACS and were included in this study (3294 in the ACS-I registry, 1956 in the ACS-II registry, 7543 in GRACE, and 1318 in CANRACE). Over time, there was a substantial increase in the use of dual anti-platelet (aspirin and thienopyridine) therapy (P for trend <.001), and in rates of in-hospital cardiac catheterization and percutaneous coronary intervention (both Ps for trend <.001). Overall, major bleeding was relatively infrequent (1.7%). There was no significant increase in the unadjusted rates of major bleeding over time (P for trend = .19). In multivariable analysis adjusting for GRACE risk score and intensive treatment, enrolment period was not an independent predictor of bleeding (P for trend = .98). There was no interaction between the enrolment period and the use of intensive medical and invasive management. CONCLUSION: Despite more widespread use of dual anti-platelet therapies and invasive cardiac procedures in the management of NSTE-ACS, the rate of major bleeding remains relatively low and has not increased significantly over time. Our findings suggest that physicians selectively target treatment for their patients, and these evidence-based therapies can be safely administered to ACS patients in clinical practice.