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Background: Cardiac magnetic resonance imaging (CMR) can accurately determine infarct size. Prior studies using indirect methods to assess infarct size have shown that patients with larger myocardial infarctions have a worse prognosis than those with smaller myocardial infarctions., Objectives: This study assessed the prognostic significance of infarct size determined by CMR., Methods: Cine and contrast CMR were performed in 100 patients with coronary artery disease (CAD) undergoing routine cardiac evaluation. Infarct size was determined by planimetry. We used Cox proportional hazards regression analyses (stepwise forward selection approach) to evaluate the risk of all-cause death associated with traditional cardiovascular risk factors, symptoms of heart failure, medication use, left ventricular ejection fraction, left ventricular mass, angiographic severity of CAD and extent of infarct size determined by CMR., Results: Ninety-one patients had evidence of myocardial infarction by CMR. Mean follow-up was 4.8±1.6 years after CMR, during which time 30 patients died. The significant multivariable predictors of all-cause mortality were extent of myocardial infarction by CMR, extent of left ventricular systolic dysfunction, symptoms of heart failure, and diabetes mellitus (P<.05). The presence of infarct greater than or equal to 24% of left ventricular mass and left ventricular ejection fraction less than or equal to 30% were the most optimal cut-off points for the prediction of death with bivariate adjusted hazard ratios of 2.11 (95% confidence interval 1.02-4.38) and 4.06 (95% confidence interval 1.73-9.54), respectively., Conclusions: The extent of myocardial infarction determined by CMR is an independent predictor of death in patients with CAD., (Copyright © 2011. Published by Elsevier Inc.)

Background: Myocardial rupture is a relatively rare and usually fatal complication of myocardial infarction (MI). Early recognition of patients at greatest risk of myocardial rupture provides an opportunity for early intervention., Methods: VALIANT was a double-blind, randomized, controlled trial comparing valsartan, captopril, and their combination in high-risk patients post-MI. Myocardial rupture was identified by autopsy (available in 138/589 patients dying within 30 days of index MI), echocardiography, direct surgical visualization, or presence of hemopericardium. An independent clinical end points committee reviewed medical records for all deaths or suspected nonfatal cardiovascular events., Results: Rupture was identified in 45 (0.31%) patients enrolled in VALIANT, occurring 9.8 +/- 6.0 days after the qualifying MI. Rupture accounted for 7.6% (45/589) of all deaths occurring in the first 30 days of follow-up and 24% (33/138) of deaths in which autopsies were obtained. Compared with survivors, rupture was associated with increased age, hypertension, increased Killip class, lower estimated glomerular filtration rate, and Q wave MI, and inversely related to beta-blocker and diuretic use. Compared with patients who died of other causes within 30 days, patients with myocardial rupture were more likely to have had an inferior MI, Q wave MI, or hypertension; to have used oral anticoagulants; or to have received thrombolytic therapy., Conclusions: Although rare, myocardial rupture accounted for nearly one fourth of all deaths within the first 30 days after high-risk MI, suggesting an estimated incidence of approximately 1% within the first 30 days. A number of clinical characteristics may identify post-MI patients at higher risk of myocardial rupture., (Copyright (c) 2010 Mosby, Inc. All rights reserved.)

Background: Intramyocardial fat deposition occurs as an age-related process and in multiple pathologic processes., Objective: We evaluated the presence of left ventricular (LV) and right ventricular (RV) intramyocardial fat with 64-slice multidetector computed tomography (MDCT)., Methods: One hundred persons with no history of coronary artery disease (47 women, 53 men; mean age [+/- SD], 53 +/- 12.2 years) and 25 patients with CT findings of myocardial infarction (17 men, 8 women; mean age, 71.3 +/- 9.6 years) were studied for intramyocardial fat in defined segments of the ventricles (17 LV and 10 RV segments) at 3 levels. Fat deposition was defined as density range of -30 to -190 Hounsfield units on images both before and after contrast., Results: In healthy persons, LV intramyocardial fat was primarily located in the basal segments (5% anteroseptal, 5% inferior), and RV intramyocardial fat was primarily located in the anterolateral (24% of base, 23% of mid) and inferolateral (27% base, 27% mid) segments. Older age was associated with an increased odds of RV (sex-adjusted odds ratio [OR] per decade increment, 1.61; 95% confidence interval [CI], 1.11-2.33; P = 0.012) but not LV (OR, 0.97; 95% CI, 0.67-1.40; P = 0.85) intramyocardial fat. Compared with women, men had a lower risk of LV (95% CI, 0.1-0.64; P = 0.004) but not RV (95% CI, 0.35-1.87; P = 0.62) intramyocardial fat. Patients with old myocardial infarction (>3 years) had increased percentage of fat in infarcted left ventricles at all 3 levels (P

Background: Left ventricular systolic dysfunction (LVSD) and heart failure (HF) are powerful predictors of poor outcome after acute myocardial infarction (MI). It is not known, however, whether the extent of coronary artery disease (CAD) independently influences cardiovascular (CV) outcomes in these high-risk patients., Methods: In the VALIANT, 14703 patients were randomly assigned to receive either captopril monotherapy, valsartan monotherapy, or a valsartan and captopril combination between 0.5 and 10 days after acute MI complicated by LVSD, HF, or both. Cox proportional hazards models were used to evaluate the relation between the extent of CAD (the number of diseased vessels as assessed by angiography) and a range of CV outcomes and all-cause mortality., Results: Coronary angiography data were available on 5742 (40%) of the 14703 randomized patients. Single-vessel disease was reported in 1955 patients (34%), 2-vessel disease in 1598 (28%), and 3-vessel disease in 2189 (38%). For all CV outcomes, the risk increased with the severity of CAD (P for trend < .002). A comparison of single-, 2-, and 3-vessel disease showed that, after adjusting for all known covariates, including revascularization and ejection fraction, 2-vessel disease was associated with a 40% increased hazard (P = .008) and 3-vessel disease was associated with an 85% increased hazard (P < .001) for all-cause mortality. The fully adjusted hazard ratios for death and other CV outcomes increased significantly with increasing extent of CAD., Conclusions: Increasing extent of CAD, as detected by angiography, is a significant and independent risk factor for adverse CV outcomes after MI complicated by HF, LVSD, or both. The observed risk was apparent even after excluding patients who had undergone revascularization.

Background: Persons with end-stage renal disease and those with lesser degrees of chronic kidney disease (CKD) have an increased risk of death after myocardial infarction (MI) that is not fully explained by associated comorbidities. Future cardiovascular event rates and the relative response to therapy in persons with mild to moderate CKD are not well characterized., Methods and Results: We calculated the estimated glomerular filtration rate (eGFR) using the 4-variable Modification of Diet in Renal Disease method in 2183 Survival And Ventricular Enlargement (SAVE) trial subjects. SAVE randomized post-MI subjects (3 to 16 days after MI) with left ventricular ejection fraction < or =40% and serum creatinine <2.5 mg/dL to captopril or placebo. Cox proportional hazards models were used to evaluate the relative hazard rates for death and cardiovascular events associated with reduced eGFR. Subjects with reduced eGFR were older and had more extensive comorbidities. The multivariable adjusted risk ratio for total mortality associated with reduced eGFR from 60 to 74, 45 to 59, and <45 mL x min(-1) x 1.73 m(-2) (compared with eGFR > or =75 mL x min(-1) x 1.73 m(-2)) was 1.11 (0.86 to 1.42), 1.24 (0.96 to 1.60) and 1.81 (1.32 to 2.48), respectively (P for trend =0.001). Similar adjusted trends were present for CV mortality (P=0.001), recurrent MI (P=0.017), and the combined CV mortality and morbidity outcome (P=0.002). The absolute benefit of captopril tended to be greater in subjects with CKD: 12.4 versus 5.5 CV events prevented per 100 subjects with (n=719) and without (n=1464) CKD, respectively., Conclusions: CKD was associated with a heightened risk for all major CV events after MI, particularly among subjects with an estimated glomerular filtration rate <45 mL x min(-1) x 1.73 m(-2). Randomization to captopril resulted in a reduction of CV events irrespective of baseline kidney function.

Background: Hypertension is a well-established risk factor for myocardial infarction (MI), but its prognostic importance in survivors of an acute MI is less clear., Methods: We used Cox proportional hazards models to examine the risk of any major cardiovascular event (cardiovascular death, heart failure, recurrent MI, or stroke)-combined or individual components-and all-cause death and evaluate the efficacy of captopril in 906 patients with hypertension and 1325 patients without hypertension in the Survival and Ventricular Enlargement (SAVE) clinical trial. All patients had survived an acute MI with resultant left ventricular (LV) systolic dysfunction, but without overt heart failure, and were randomized within 3 to 16 days after the index MI to receive either captopril or placebo. The mean (+/- SD) follow-up period was 42 +/- 10 months., Results: After adjustment for known risk factors, medication use at enrollment, and baseline systolic blood pressure, patients with hypertension had a significant increase in the risk of experiencing a combined cardiovascular event (47.7% vs 31.3%; hazard ratio [HR], 1.49; 95% CI, 1.28-1.74), cardiovascular death (23.4% vs 15.9%; HR, 1.40; 95% CI, 1.12-1.74), heart failure (27.7% vs 15.5%; HR, 1.64; 95% CI, 1.34-2.02), and all-cause death (27.4 vs 19.3%; HR, 1.25; 95% CI, 1.02-1.53), and a similar but statistically non-significant increase in the risk of non-fatal or fatal recurrent MI (17.4% vs 10.9%; HR, 1.27; 95% CI, 0.98-1.65), and non-fatal or fatal stroke (5.0% vs 3.6%; HR, 1.31; 95% CI, 0.81-2.09). Captopril resulted in similar benefits for both patients with and patients without hypertension. The number of combined cardiovascular events prevented for every 100 patients treated with captopril was 7.0 (95% CI, 0.5-13.5) in patients with hypertension and 7.5 (95% CI, 2.6-12.5) in patients without hypertension., Conclusions: In survivors of an acute MI with LV systolic dysfunction, antecedent hypertension was associated with a greater risk of subsequent adverse cardiovascular events, not directly explained by elevated blood pressure levels. Captopril use was beneficial in both patients with and patients without hypertension.

Whether antecedent systemic hypertension influences the risk of subsequent left ventricular (LV) dilation in patients after an acute myocardial infarction with LV systolic dysfunction is unclear. We assessed echocardiographic evidence of ventricular remodeling from baseline (mean +/- SD 11 +/- 3 days) to 2 years after an acute myocardial infarction in 122 hypertensive (defined as a history of treated hypertension, baseline systolic blood pressure > or =140 or baseline diastolic blood pressure > or =90 mm Hg) and 334 nonhypertensive patients in the Survival and Ventricular Enlargement echocardiographic substudy. Compared with nonhypertensives, baseline heart size, defined as the sum of the average short- and long-axis LV cavity areas, was similar (70.1 +/- 11.9 vs 68.8 +/- 11.2 cm(2), p = 0.33 at end-diastole; 50.1 +/- 11.3 vs 48.8 +/- 10.8 cm(2), p = 0.31 at end-systole), but short-axis LV myocardial area (24.7 +/- 4.3 vs 25.7 +/- 5.0 cm(2), p = 0.043) and wall thickness (1.15 +/- 0.16 vs 1.21 +/- 0.17 cm, p = 0.004) at end-diastole were greater among hypertensives. The myocardial infarct segment lengths were similar in the 2 groups (p = 0.22). Although LV cavity areas increased significantly in the 2 groups from baseline to 2 years (p < or =0.001), the increase was significantly greater in hypertensives than in nonhypertensives (+5.6 +/- 11.5 vs +2.2 +/- 10.7 cm(2), p = 0.005 at end-diastole; +6.23 +/- 12.75 vs +2.94 +/- 11.4 cm(2), p = 0.012 at end-systole). There was no concomitant difference in the change in LV myocardial area or LV wall thickness between the 2 groups (p >0.30). After adjusting for known confounders, antecedent hypertension was associated with a doubling of the risk of LV dilation (50.8% vs 37.7%, odds ratio 2.09, 95% confidence interval 1.27 to 3.45, p = 0.004). This association was not modified by diabetes mellitus, myocardial infarct segment length, or captopril use (all p values for interaction >0.10). We conclude that antecedent hypertension is associated with subsequent LV dilation in patients after acute myocardial infarction with LV systolic dysfunction.

Current evidence suggests that routine invasive therapy in the setting of unstable angina/non-ST-segment elevation myocardial infarction (UA/NSTEMI) reduces the incidence of composite end points (i.e., death, myocardial infarction, or angina.). The 2002 American College of Cardiology/American Heart Association guidelines recommend invasive therapy in high-risk patients, although it is unknown if such an approach improves survival. We conducted a meta-analysis on 5 studies in 6,766 UA/NSTEMI patients who were randomized to either routine invasive versus conservative therapy in the era of glycoprotein IIb/IIIa inhibitors and intracoronary stents. Compared with conservative therapy, an invasive approach suggested a reduction in mortality at 6 to 12 months (risk ratio [RR] 0.80, 95% confidence interval [CI] 0.63 to 1.03) and at 24 months (RR 0.77, 95% CI 0.60 to 0.99). The composite end point of death or myocardial infarction was reduced throughout all periods of follow-up: at 30 days (RR 0.61, 95% CI 0.45 to 0.84), at 6 months (RR 0.75, 95% CI 0.63 to 0.89), and at 12 months (RR 0.78, 95% CI 0.65 to 0.92). For the same composite end point at 6 to 12 months, men benefited from invasive therapy (RR 0.68, 95% CI 0.57 to 0.81), as did troponin-positive patients (RR 0.74, 95% CI 0.59 to 0.94). The results for women (RR 1.07, 95% CI 0.82 to 1.41) and troponin-negative patients (RR 0.82, 95% CI 0.59 to 1.14) were equivocal. Routine invasive therapy in UA/NSTEMI patients along with adjunctive use of glycoprotein IIb/IIIa inhibitors and intracoronary stents improves survival. Enhanced risk stratification is needed in women and troponin-negative patients so that invasive therapy may be more effectively recommended in these groups.

Patients with type 2 diabetes mellitus are at increased risk for cardiovascular disease (CVD) and mortality. Beyond traditional CVD risk factors, novel measures reflecting additional aspects of disease pathophysiology, such as biventricular volume (BiVV), may be useful for risk stratification. The aim of this study was to examine the relationship between BiVV and risk for mortality in European Americans with type 2 diabetes mellitus from the Diabetes Heart Study (DHS). BiVV was calculated from 771 noncontrast computed tomographic scans performed to image coronary artery calcified plaque. Relationships between BiVV and traditional CVD risk factors were examined. Cox proportional-hazards regression was performed to determine risk for mortality (all-cause and CVD mortality) associated with increasing BiVV. Area under the curve analysis was used to assess BiVV utility in risk prediction models. During 8.4 ± 2.4 years of follow-up, 23% of the patients died. In unadjusted analyses, BiVV was significantly associated with increasing body mass index, height, coronary artery calcified plaque, history of hypertension, and previous myocardial infarction (p <0.0001 to 0.012). BiVV was significantly associated with all-cause (hazard ratio 2.45, 95% confidence interval 1.06 to 5.67, p = 0.036) and CVD (hazard ratio 4.36, 95% confidence interval 1.36 to 14.03, p = 0.014) mortality in models adjusted for other known CVD risk factors. Area under the curve increased from 0.76 to 0.78 (p = 0.04) and from 0.74 to 0.77 (p = 0.02) for all-cause and CVD mortality with the inclusion of BiW. In conclusion, in the absence of echocardiography or other noninvasive imaging modalities to assess ventricular volumes, or when such methods are contraindicated, BiVV from computed tomography may be considered a tool for the stratification of high-risk patients, such as those with type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]