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Despite significant advances in its treatment, acute myocardial infarction (AMI) remains an important cause of heart failure (HF). Contemporary data remain lacking, however, describing long-term trends in incidence rates, demographic and clinical profiles, and outcomes of patients who develop HF as a complication of AMI. Our study sample consisted of 11,061 residents of the Worcester (Massachusetts) metropolitan area hospitalized with AMI at all greater Worcester hospitals in 15 annual study periods from 1975 to 2005. Overall, 32.4% of patients (n = 3,582) with AMI developed new-onset HF during their acute hospitalization. Patients who developed HF were generally older, more likely to have pre-existing cardiovascular disease, and were less likely to receive cardiac medications or undergo revascularization procedures during their hospitalization than patients who did not develop HF (p <0.001). Incidence rates of HF remained relatively stable from 1975 to 1991 at 26% but decreased thereafter. Decreases were also noted in hospital and 30-day death rates in patients with acute HF (p <0.001). However, patients who developed new-onset HF remained at significantly higher risk for dying during their hospitalization (21.6%) than patients who did not develop this complication (8.3%, p <0.001). Our large community-based study of patients hospitalized with AMI demonstrates that incidence rates of and mortality attributable to HF have decreased over the previous 3 decades. In conclusion, HF remains a common and frequently fatal complication of AMI to which increased surveillance and treatment efforts should be directed. [ABSTRACT FROM AUTHOR]

Poor R-wave progression (PRWP) is a common electrocardiographic phenomenon in which the anticipated increase in R-wave amplitude in successive precordial leads, V1 to V5, fails to occur. PRWP is prevalent in approximately 10% of hospitalized adult patients, predominantly in those with coronary artery disease. Debate is ongoing on its association with myocardial infarction (MI). However, studies that showed no association failed to appraise the significance of the QRS axis in relation to PRWP among such patients with MI. In our retrospective study, we consecutively identified 150 unselected adult patients with PRWP among 660 successive admissions to the general medical floors of a tertiary care teaching hospital (Saint Vincent Hospital, Worcester, Massachusetts). After excluding patients with anterior wall Q-wave MI (defined as the presence of a QS complex or Q-wave ≥1 mm deep in V2 or V3), sudden unexpected death, MI after percutaneous coronary interventions or coronary artery bypass grafting during this hospitalization, Wolff-Parkinson-White syndrome, pacemakers, bundle branch blocks, and electrocardiograms that were of poor quality or affected by severe motion artifact, inconsistencies with patient identification, or errors in lead placement, 137 patients remained. The patients were then screened for non–ST-segment elevation MI (NSTEMI) during the present admission. The DePace criteria for PRWP were systematically used for all patients, and the QRS axis was calculated using limb leads based on Einthoven''s equilateral triangle (normal was considered −30° to 100°). Of the 137 study patients screened with PRWP, 38 had NSTEMI (25.3%). Thirty-one had a normal QRS axis (mean age ± standard deviation 71.3 ± 12 years), and 7 showed either right or left axis deviation (mean age ± standard deviation 64.3 ± 15 years). This proved to be statistically significant (p <0.0001) within this cohort of NSTEMI patients. In conclusion, PRWP determined using the DePace criteria in the presence of a normal QRS axis appears to be more significantly associated with the presence of overall MI within this cohort of NSTEMI patients. [Copyright &y& Elsevier]

Atrial fibrillation (AF) is a common complication of acute myocardial infarction (AMI) and this arrhythmia is associated with increased morbidity and mortality in patients with AMI. Limited information is available, however, about changing, and contemporary, trends in the incidence and death rates associated with AF complicating AMI. We examined the magnitude and impact of AF and the risk of stroke and hospital and long-term death rates in a population-based study of patients hospitalized with AMI. The study population consisted of 7,513 residents of the Worcester, Massachusetts, metropolitan area hospitalized with AMI at all greater Worcester medical centers during 9 biennial years from 1990 to 2005. Overall incidence of AF complicating AMI was 13.3% and rates of AF increased during the most recent years under study. Patients who developed AF were at greater risk for acute stroke (adjusted odds ratio 2.25, 95% confidence interval 1.36 to 3.71) and dying during hospitalization (adjusted odds ratio 1.79, 95% confidence interval 1.46 to 2.19) compared with patients who did not develop AF during hospitalization for AMI. Postdischarge survival was significantly poorer in patients who developed AF. Odds of dying after AF did not change appreciably over the years under study. In conclusion, results of this study in residents of a large New England metropolitan area suggest that AF remains a frequent complication of AMI and is associated with a poor prognosis. Increased surveillance and targeted therapeutic approaches appear warranted for these high-risk patients. [Copyright &y& Elsevier]

Delay in seeking medical care after symptom onset in patients with an acute myocardial infarction (AMI) is related to increased morbidity and mortality. Duration of prehospital delay in patients hospitalized with AMI has not been well characterized over time, and potentially changing patient characteristics associated with prolonged delay are not well understood. The study sample consisted of 5,967 residents (mean age 76 years; 39% women) of the Worcester, Massachusetts, metropolitan area hospitalized with AMI in 11 annual periods from 1986 to 2005. Mean and median delay times have remained essentially unchanged during the past 2 decades. Mean and median prehospital delay times were 4.1 and 2.0 hours in 1986, 4.7 and 2.2 hours in 1995, and 4.6 and 2.0 hours in 2005, respectively. Approximately 45% of patients with AMI presented within 2 hours of acute symptom onset, whereas an additional one third presented from 2 to 6 hours after the onset of acute coronary symptoms. Advancing age and history of either diabetes or MI were associated with prolonged delay. Compared with patients arriving within 2 hours of symptom onset, those with prolonged prehospital delay were less likely to receive thrombolytic therapy and percutaneous coronary intervention within 90 minutes of hospital arrival. In conclusion, results of this population-based study suggest that a large proportion of patients with AMI continue to show prolonged prehospital delay. [Copyright &y& Elsevier]

Limited contemporary data are available describing the incidence rates, hospital prognosis, and factors associated with the occurrence of ventricular fibrillation (VF) in patients hospitalized with acute myocardial infarction (AMI). The objectives of our study were to examine 3-decade-long trends (1975 to 2005) in the magnitude, predictors, and hospital case-fatality rates associated with VF in residents of a large New England metropolitan area hospitalized at all area medical centers with an uncomplicated AMI. The study population consisted of 7,472 residents of the Worcester (Massachusetts) metropolitan area hospitalized with an uncomplicated AMI in 15 annual periods from 1975 to 2005. The overall proportion of patients who developed VF was 4.2%. The incidence rates of VF remained stable from 1975 to 1995 but decreased thereafter, reaching their lowest frequency in 2005 (1.9%). Hospital case-fatality rates were significantly higher in patients with (40.9%) compared with those without (2.5%) VF. Decreases in hospital death rates over time were observed in patients with and without VF, with the decreases in death rates being greater for patients with VF. Patients who developed a Q-wave MI or a left or right bundle branch block were at particularly increased risk for developing VF. In conclusion, our results indicate that the incidence and hospital death rates associated with VF have decreased during recent years. [Copyright &y& Elsevier]