Susan A. Weston

Heart Failure and Death After Myocardial Infarction in the Community: The Emerging Role of Mitral Regurgitation

Background—In case series, mitral regurgitation (MR) increased the risk of death after myocardial infarction (MI), yet the prevalence of MR, its incremental prognostic value over ejection fraction (EF), and its association with heart failure and death after MI in the community is not known. Methods and Results—The prevalence of MR and its association with heart failure and death were examined among 1331 patients within a geographically defined MI incidence cohort between 1988 and 1998. Echocardiography was performed within 30 days after MI in 773 patients (58%), and MR was present in 50% of cases, mild in 38%, and moderate or severe in 12%. Among patients with MR, a murmur was inconsistently detected clinically. After 4.7±3.3 years of follow-up, 109 episodes of heart failure and 335 deaths occurred. There was a graded positive association between the presence and severity of MR and heart failure or death. Moderate or severe MR was associated with a large increase in the risk of heart failure (relative risk 3.44, 95% CI 1.74 to 6.82, P<0.001) and death (relative risk 1.55, 95% CI 1.08 to 2.22, P=0.019) among 30-day survivors independent of age, gender, EF, and Killip class. Conclusions—In the community, MR is frequent and often silent after MI. It carries information to predict heart failure or death among 30-day survivors independently of age, gender, EF, and Killip class. These findings, which are applicable to a large community-based MI cohort, suggest that the assessment of MR should be included in post-MI risk stratification.

Coronary atherosclerosis in diabetes mellitus: A population-based autopsy study

OBJECTIVES The study was conducted to test the hypothesis that the prevalence of coronary atherosclerosis is greater among diabetic than among nondiabetic individuals and is similar for diabetic individuals without clinical coronary artery disease (CAD) and nondiabetics with clinical CAD. BACKGROUND Persons with diabetes but without clinical CAD encounter cardiovascular mortality similar to nondiabetic individuals with clinical CAD. This excess mortality is not fully explained. We examined the association between diabetes and coronary atherosclerosis in a geographically defined autopsied population, while capitalizing on the autopsy rate and medical record linkage system available via the Rochester Epidemiology Project, which allows rigorous ascertainment of coronary atherosclerosis, clinical CAD, and diabetes. METHODS Using two measures, namely a global coronary score and high-grade stenoses, the prevalence of atherosclerosis was analyzed in a cohort of autopsied residents of Rochester, Minnesota, age 30 years or older at death, while stratifying on diabetes, clinical CAD diagnosis, age, and gender. RESULTS In this cohort, diabetes was associated with a higher prevalence of atherosclerosis. Among diabetic decedents without clinical CAD, almost three-fourths had high-grade coronary atherosclerosis and more than half had multivessel disease. Without diabetes, women had less atherosclerosis than men, but this female advantage was lost with diabetes. Among those without clinical CAD, diabetes was associated with a global coronary disease burden and a prevalence of high-grade atherosclerosis similar to that observed among nondiabetic subjects with clinical CAD. CONCLUSIONS These findings provide mechanistic insights into the excess risk of clinical CAD among diabetic individuals, thereby supporting the need for aggressive prevention of atherosclerosis in all diabetic individuals, irrespective of clinical CAD symptoms.

Hospitalizations After Heart Failure Diagnosis: A Community Perspective

OBJECTIVES The purpose of this study was to determine the lifetime burden and risk factors for hospitalization after heart failure (HF) diagnosis in the community. BACKGROUND Hospitalizations in patients with HF represent a major public health problem; however, the cumulative burden of hospitalizations after HF diagnosis is unknown, and no consistent risk factors for hospitalization have been identified. METHODS We validated a random sample of all incident HF cases in Olmsted County, Minnesota, from 1987 to 2006 and evaluated all hospitalizations after HF diagnosis through 2007. International Classification of Diseases-9th Revision codes were used to determine the primary reason for hospitalization. To account for repeated events, Andersen-Gill models were used to determine the predictors of hospitalization after HF diagnosis. Patients were censored at death or last follow-up. RESULTS Among 1,077 HF patients (mean age 76.8 years, 582 [54.0%] female), 4,359 hospitalizations occurred over a mean follow-up of 4.7 years. Hospitalizations were common after HF diagnosis, with 895 (83.1%) patients hospitalized at least once, and 721 (66.9%), 577 (53.6%), and 459 (42.6%) hospitalized > or =2, > or =3, and > or =4 times, respectively. The reason for hospitalization was HF in 713 (16.5%) hospitalizations and other cardiovascular in 936 (21.6%), whereas over one-half (n = 2,679, 61.9%) were noncardiovascular. Male sex, diabetes mellitus, chronic obstructive pulmonary disease, anemia, and creatinine clearance <30 ml/min were independent predictors of hospitalization (p < 0.05 for each). CONCLUSIONS Multiple hospitalizations are common after HF diagnosis, though less than one-half are due to cardiovascular causes. Comorbid conditions are strongly associated with hospitalizations, and this information could be used to define effective interventions to prevent hospitalizations in HF patients.

Trends in Incidence, Severity, and Outcome of Hospitalized Myocardial Infarction

Background— In 2000, the definition of myocardial infarction (MI) changed to rely on troponin rather than creatine kinase (CK) and its MB fraction (CK-MB). The implications of this change on trends in MI incidence and outcome are not defined. Methods and Results— This was a community study of 2816 patients hospitalized with incident MI from 1987 to 2006 in Olmsted County, Minnesota, with prospective measurements of troponin and CK-MB from August 2000 forward. Outcomes were MI incidence, severity, and survival. After troponin was introduced, 278 (25%) of 1127 incident MIs met only troponin-based criteria. When cases meeting only troponin criteria were included, incidence did not change between 1987 and 2006. When restricted to cases defined by CK/CK-MB, the incidence of MI declined by 20%. The incidence of non–ST-segment elevation MI increased markedly by relying on troponin, whereas that of ST-segment elevation MI declined regardless of troponin. The age- and sex-adjusted hazard ratio of death within 30 days for an infarction occurring in 2006 (compared with 1987) was 0.44 (95% confidence interval, 0.30 to 0.64). Among 30-day survivors, survival did not improve, but causes of death shifted from cardiovascular to noncardiovascular (P=0.001). Trends in long-term survival among 30-day survivors were similar regardless of troponin. Conclusions— Over the last 2 decades, a substantial change in the epidemiology of MI occurred that was only partially mediated by the introduction of troponin. Non–ST-segment elevation MIs now constitute the majority of MIs. Although the 30-day case fatality improved markedly, long-term survival did not change, and the cause of death shifted from cardiovascular to noncardiovascular.

Trends in the incidence and survival of patients with hospitalized myocardial infarction, Olmsted County, Minnesota, 1979 to 1994.

Context Mortality from coronary disease and the number of people hospitalized for myocardial infarction have decreased in recent years. Medical care or reduced incidence of disease could be responsible. Contribution Between 1979 and 1994, age-adjusted incidence of myocardial infarction in Olmsted County, Minnesota, changed little overall, although it decreased 8% in men, increased 36% in women, and increased in older compared with younger persons. Mortality rates from myocardial infarction decreased in younger but not older persons. Implications Secular trends in myocardial infarction reflect changes in both incidence and survival and vary significantly with sex and age. The Editors Although age-adjusted mortality due to coronary disease had decreased in recent decades, the continuing burden of coronary disease should not be underestimated, and the determinants of this decrease have not been fully elucidated. Recent data from the United States indicate that the incidence of hospitalized myocardial infarction decreased modestly in recent years (1, 2), suggesting that medical care has contributed greatly to the decrease in mortality. Conversely, the World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease study conversely found that changes in incidence were the major reason for the decrease in deaths from coronary disease (3). These divergent findings warrant further analyses in different populations. Moreover, because neither of these studies included persons older than 74 years of age, trends among elderly persons, the fastest growing segment of the population, could not be measured (1, 3-5). The Worcester Heart Attack Study showed that survival after myocardial infarction improved over time, but advancing age had a markedly adverse effect on survival (6). Although the explanations for these adverse findings are probably multifactorial and include more comorbid conditions and less use of efficacious therapies in elderly persons, these results emphasize the importance of monitoring coronary disease trends in this group. Data from Olmsted County, Minnesota, for persons of all ages indicated that the decrease in coronary mortality affected primarily middle-aged men; this finding suggests that the burden of coronary deaths has been shifted toward women and elderly persons (7). These data further highlight the importance of including older age groups in studies and the need to elucidate age- and sex-specific mortality trends. We sought to examine the trends in incidence and survival of patients with hospitalized myocardial infarction in Olmsted County, Minnesota. We tested two hypotheses: 1) that the incidence of myocardial infarction has not decreased overall over time, but that trends differ by sex and age, and 2) that survival after incident myocardial infarction has improved over time but that the magnitude of improvement differs by sex and age. Methods Setting Epidemiologic research in Olmsted County, Minnesota, is possible because the county is relatively isolated from other centers, and a few providers deliver nearly all medical care to local residents. The Mayo Clinic provides approximately half of the primary care and nearly all specialty care to the region, and Olmsted Medical Center and its affiliate Olmsted Community Hospital provide care for the region in every medical field. The characteristics of the Olmsted County population are similar to those of white persons in the United States overall, except that a higher proportion of Olmsted County residents are employed in the health care sector (8). Each medical care provider uses a medical record system in which the details of every encounter are entered and can be easily retrieved; the Mayo Clinic has maintained extensive indices of clinical and histologic diagnoses and surgical procedures since the 1900s (9, 10). Since 1966, similar indices have been developed for non-Mayo Clinic providers through the Rochester Epidemiology Project, resulting in the linkage of medical records from all sources of care used by the population. This system provides a unique infrastructure for analyzing disease determinants and outcomes. Enumeration of Hospitalized Patients with Acute Myocardial Infarction Case Finding and Investigation Lists of patients discharged from hospitals in Olmsted County who had diagnoses compatible with myocardial infarction were obtained from the Rochester Epidemiology Project index of diagnoses and the Hospital Utilization Review Database, an administrative database of hospitalizations maintained by the Mayo Clinic. The target International Classification of Diseases, Ninth Revision, codes were 410 (acute myocardial infarction), 411 (other acute and subacute forms of ischemic heart disease), 412 (old myocardial infarction), 413 (angina pectoris), and 414 (other forms of ischemic heart disease). All events coded as 410, a 50% random sample of code 411, and a 10% random sample of codes 412, 413, and 414 were reviewed. The sampling fractions were similar to those used in other studies (11). Trained abstracters reviewed the medical records of Olmsted County residents and collected information on cardiac pain (defined as pain occurring in the anterior chest, arms or jaw, back, shoulder, or abdomen) and timing of its onset. Pain was categorized as present if it met these criteria and no other cause of pain could be determined (11). Creatinine phosphokinase values were transcribed for up to three measurements on each of the first 3 days after admission. Information on a potential history of trauma or surgery, which might invalidate enzyme values, was recorded. Copies of up to three electrocardiograms (from the first day of the event or hospital admission, the last day of hospitalization, and the third day) were printed and sent to the Electrocardiogram Reading Center at the University of Minnesota to assign a Minnesota code (12). Determination of Incident Status of Myocardial Infarction The full medical record of each candidate case was searched for any episode compatible with previous infarction. Abstracters were asked to first examine the history surrounding the index event. If no previous cardiac history was specifically mentioned, the search for antecedent infarction was terminated. If a previous infarction was mentioned or if nothing was specified, all records before the index event were examined. If data were available, the possible antecedent event was validated by using the classification rule described below. If data were unavailable, the event was described qualitatively on the basis of the available documentation (confirmed by attending physician, history of heart attack according to the patient, mention of silent infarction without further descriptor, or mention of old infarction on physicians review of a routine electrocardiogram). Classification of the Index Hospitalized Myocardial Infarction Once the data for a hospitalized myocardial infarction were collected, a standardized classification rule was applied to assign an epidemiologic diagnosis (5, 11, 13). Cardiac pain was categorized as present or absent, and enzyme values were classified as abnormal, equivocal, or normal. When review by a physician-author confirmed a potential nonischemic cause of elevated enzyme levels, the classification was downgraded to equivocal. According to the Minnesota system, one of five codes was assigned to the electrocardiograms (evolving diagnostic, diagnostic, evolving ST-T changes, equivocal, or absent). According to the classification rule, myocardial infarctions were classified as definite, probable, suspect, or no myocardial infarction on the basis of cardiac pain, enzyme, and electrocardiographic data. According to published criteria (13), fatal myocardial infarction can be definitively diagnosed if the patient had a definite hospitalized infarction within 4 weeks of death or an acute infarction was found at autopsy. Of hospitalized persons with discharge codes 410 to 414, those who died in the emergency department, those who were dead on arrival, and those with in-hospital events with a rapid fatal course for whom no or little data were available were categorized as having infarction if they had an autopsy diagnosis of myocardial infarction. Follow-up In hospitalized patients, vital status was determined at discharge. Thereafter, it was determined by verification of death certificates, performed by the Rochester Epidemiology Project. Reliability of the Myocardial Infarction Ascertainment Process The abstracters were trained in methods for case finding and residency ascertainment through the Rochester Epidemiology Project. Quality control involved reabstraction of a random sample of 19 cases. The coefficient was used to evaluate interobserver variability for categorical variables. By convention, arbitrary categories were used to define poor ( 0.4), fair to good (0.4 < 0.7), and excellent ( > 0.7) agreement beyond chance. Categorical variables were history of myocardial infarction and cardiac pain. Agreement was excellent for history of infarction ( = 0.92 [(95% CI, 0.79 to 1.0)], presence of cardiac pain ( = 0.93 [CI, 0.84 to 1.0]), and presence of prolonged cardiac pain ( = 0.96 [CI, 0.88 to 1.0]). Statistical Analysis Age-, sex-, and year-specific incidences of hospitalized myocardial infarction were calculated. The numerators were the number of all definite and probable incident infarctions, and the denominators were the Olmsted County population as determined from census data for the years 1970, 1980, and 1990, with linear interpolation for the intercensus years and extrapolation after 1990 (14). Rates were directly adjusted to the age distribution of the 2000 U.S. population. Standard errors and 95% CIs were calculated on the basis of the Poisson error distribution. Age- and sex-specific trends in the incidence of hospitalized myocardial infarction were assessed by using weighted Poisson regression. The analyse

Death in Heart Failure: a Community Perspective

Background—Mortality in patients with heart failure (HF) remains high, but causes of death are incompletely defined. As HF is a heterogeneous syndrome categorized according to the ejection fraction (EF), the association between EF and causes of death is important, yet elusive. Methods and Results—Community subjects with HF were classified according to the preserved (≥50%) and the reduced EF (<50%). Deaths were classified as due to coronary heart disease and other cardiovascular and noncardiovascular diseases. Among 1063 persons with HF, 45% had preserved EF with fewer cardiovascular risk factors and less coronary disease than those with reduced EF. At 5 years, survival was 45% (95% CI, 43% to 49%), and 43% of the deaths were noncardiovascular. The leading cause of death in subjects with preserved EF was noncardiovascular disease (49%) versus coronary heart disease (43%) for subjects with reduced EF. The proportion of cardiovascular deaths decreased from 69% in 1979–1984 to 40% in 1997–2002 (P=0.007) among subjects with preserved EF, which is in contrast to a modest change among those with reduced EF (77% to 64%, P=0.08). Advanced age, male sex, diabetes, smoking, and kidney disease were associated with an increased risk of all-cause and cardiovascular deaths. After adjustment, preserved EF was associated with a lower risk of cardiovascular death but not all-cause death. Conclusions—Community subjects with HF experience a persistently high mortality, and a large proportion of deaths is noncardiovascular. Cardiovascular disease before death is less in subjects with preserved EF, and they are less likely to experience cardiovascular deaths compared with those with reduced EF. In those with preserved EF, the proportion of cardiovascular deaths declined over time.

Prognostic value of treadmill exercise testing in elderly persons

Over the past three decades, vital statistics data have shown a great decrease in age-adjusted mortality due to heart disease (1). However, this decrease reflects a shift in the disease burden toward the older segments of the population, and heart disease remains the leading cause of death in the United States (2-4). Treadmill exercise testing is widely used to evaluate coronary artery disease. More than 800 000 treadmill exercise tests are performed in the U.S. Medicare population each year (5), of which one third are conducted by noncardiologists. Despite widespread use of treadmill exercise testing in elderly persons, the prognostic value of such testing in these persons has not been fully characterized (5). Few elderly patients were included in studies that produced and validated some of the most widely used prognostic scores calculated from treadmill exercise testing data (6, 7). The studies that included elderly patients were relatively small and did not use multivariate analysis to identify prognostic variables from treadmill exercise testing data (8, 9). A greater prevalence and severity of coronary disease and the presence of more comorbid conditions may alter the ability of treadmill exercise testing to predict outcome in elderly persons (10). In addition, increasingly sedentary lifestyle with aging and differences in exercise physiology may contribute to different interpretations of treadmill exercise testing results in elderly persons (11, 12). Furthermore, studies of the prognostic value of treadmill exercise testing have been conducted in selected populations (13, 14). Some studies consisted of symptomatic patients from referral centers who had undergone angiography (6, 13, 15-18); others included healthy persons recruited from preventive medicine clinics or cohorts of healthy volunteers (19-26). Several studies did not evaluate the incremental value of treadmill exercise testing over clinical data (8, 9, 14, 27) or were not consistent in identifying prognostic variables (5, 26). These differences may be related to different study populations. Thus, it is uncertain whether results of previous studies can be generalized to a community-dwelling population of elderly patients. This gap in knowledge, which was recognized in recent exercise testing guidelines (5), calls for data obtained in more representative samples of the population. We sought to examine the outcome of treadmill exercise testing in a geographically defined population, to characterize the treadmill exercise testing variables associated with outcome, and to test the hypothesis that the prognostic value of exercise treadmill testing is similar in elderly and younger persons. Methods Setting The population of Olmsted County, Minnesota, is served by a largely unified medical care system that has accumulated comprehensive clinical records over an extended period. In 1990, the population was 96% white; except for the fact that a higher proportion of the working population is employed in the health care industry, the characteristics of the population of Olmsted County are similar to those of white persons in the United States as a whole (27). Epidemiologic research in Olmsted County is possible because the Mayo Clinic and the Olmsted Medical Group deliver almost all medical care to local residents. The epidemiologic potential of this situation has been described elsewhere (27, 28). Each provider uses a unit record system that contains the details of every patient encounter. The Rochester Epidemiology Project developed an extensive indexing system that links medical records from essentially all sources of medical care used by the Olmsted County population, including nursing home placement (29). In our study, data on nursing home placement were collected for elderly persons only; follow-up for this outcome was 96% complete. Study Sample The Rochester Epidemiology Project indices, augmented by the log books of the laboratories that perform treadmill exercise testing, were used to identify a retrospective, population-based cohort of Olmsted County residents who underwent treadmill exercise testing between 1 January 1987 and 31 December 1989. Trained nurse abstracters reviewed the medical records of potential cases. Residency in Olmsted County was verified by using information from the medical record and city and county directories. The analysis included all persons who underwent an initial treadmill exercise test. Persons with previous treadmill exercise tests were excluded. The medical records and reports of treadmill exercise tests were reviewed to collect data on demographic characteristics, symptoms, cardiovascular risk factors, comorbid conditions, and results of exercise testing. Individually recorded comorbid conditions were combined into the Charlson Comorbidity Index score (30), a prospectively validated, weighted index that takes into account the number and seriousness of comorbid diseases. Details on testing of the reliability of data collection have been published (28). Briefly, data collection was evaluated in a random sample of 20 cases. The coefficient, which measures agreement beyond that expected by chance alone, was used to evaluate interobserver and intraobserver variability. The variables included comorbid conditions, symptoms, test results, occurrence of myocardial infarction, congestive heart failure, and cause of death. Exercise Testing Persons were referred for treadmill exercise testing at the discretion of their individual physicians. The indications for treadmill exercise testing were classified as follows. 1. Evaluation of documented coronary artery disease. Documented coronary artery disease was defined by a history of myocardial infarction, presence of significant coronary disease at angiography before treadmill exercise testing, or previous revascularization procedure (coronary artery bypass grafting or coronary angioplasty). 2. Diagnostic. In this case, the patient had symptoms (dyspnea or chest pain) but no documented coronary disease. 3. Other. In the absence of cardiac symptoms or documented coronary disease, treadmill exercise testing was done for such purposes as risk stratification before noncardiac surgery or evaluation of sedentary persons before starting an exercise program. All exercise tests were performed by using standard protocols (Bruce, modified Bruce, or Naughton). The decision to interrupt therapy with medications before treadmill exercise testing was at the discretion of the attending physician. Throughout the test, symptoms, heart rate, and blood pressure were recorded. Workload was expressed in metabolic equivalents (METs). The value for METs was estimated from standard tables on the basis of protocol and duration of exercise (31). Predicted maximal functional aerobic capacity was calculated from published equations that included adjustment for age and sex (32). Persons studied were stratified into three groups defined a priori on the basis of percentage of functional aerobic capacity achieved on treadmill exercise testing: near-normal ( 85% functional aerobic capacity), intermediate (50% to 84% functional aerobic capacity), and severely abnormal (<50% functional aerobic capacity) exercise capacity (33). A positive exercise electrocardiogram was defined by using conventional criteria ( 1 mm of horizontal or down-sloping ST-segment depression or elevation for at least 60 to 80 ms after the end of the QRS complex) (5). Ascertainment of End Points The end points of interest, ascertained from the medical records, were death and cardiac events, defined as cardiac death, nonfatal myocardial infarction, or congestive heart failure. Follow-up for death was 100%. Medical records were available for ascertainment of cardiac events and nursing home placement for all patients. Deaths were classified as cardiac, cancer, or other by using the State of Minnesota death certificate files, to which the records of all Olmsted County residents are linked. For myocardial infarction, a clinical definition was used that incorporated the occurrence of chest pain typical for an ischemic origin and characteristic changes in the electrocardiogram or cardiac enzyme levels (or both). For congestive heart failure, a clinicians diagnosis was used. Statistical Analysis Comparisons between younger and elderly persons were made for several characteristics. Bivariate associations between the two age groups were tested by using chi-square tests for categorical data and t-tests for continuous variables. The KaplanMeier method was used to generate survival curves for two end points: overall mortality and cardiac event (including cardiac death, nonfatal myocardial infarction, and congestive heart failure) for each of the three exercise capacity categories. The log-rank test was used to examine differences in both end points among exercise capacity categories within the younger and elderly groups. Log-rank statistics were used to compare the survival observed in each age group, and exercise capacity category was compared with the expected survival in the age- and sex-matched population of Minnesota in 1990. Cox proportional-hazard models were constructed to determine the association of predictor variables with all-cause mortality and cardiac events; variables included were age, sex, presence of symptoms, history of myocardial infarction, history of congestive heart failure, coronary disease risk factors (history of hypertension, diabetes mellitus, smoking, hyperlipidemia, familial coronary disease), obesity (body mass index>27.3 kg/m2 for women and>27.8 kg/m2 for men), Charlson Comorbidity Index score, angina with treadmill exercise testing, positive exercise electrocardiogram, and workload achieved on treadmill exercise testing (expressed in METs). The incremental prognostic value of each of the three treadmill exercise testing variables over the clinical data was assessed separately. Separate models were constructed for younger

Clinical study: obesity, diabetes, and heart diseaseCoronary atherosclerosis in diabetes mellitus: A population-based autopsy study☆

OBJECTIVES The study was conducted to test the hypothesis that the prevalence of coronary atherosclerosis is greater among diabetic than among nondiabetic individuals and is similar for diabetic individuals without clinical coronary artery disease (CAD) and nondiabetics with clinical CAD. BACKGROUND Persons with diabetes but without clinical CAD encounter cardiovascular mortality similar to nondiabetic individuals with clinical CAD. This excess mortality is not fully explained. We examined the association between diabetes and coronary atherosclerosis in a geographically defined autopsied population, while capitalizing on the autopsy rate and medical record linkage system available via the Rochester Epidemiology Project, which allows rigorous ascertainment of coronary atherosclerosis, clinical CAD, and diabetes. METHODS Using two measures, namely a global coronary score and high-grade stenoses, the prevalence of atherosclerosis was analyzed in a cohort of autopsied residents of Rochester, Minnesota, age 30 years or older at death, while stratifying on diabetes, clinical CAD diagnosis, age, and gender. RESULTS In this cohort, diabetes was associated with a higher prevalence of atherosclerosis. Among diabetic decedents without clinical CAD, almost three-fourths had high-grade coronary atherosclerosis and more than half had multivessel disease. Without diabetes, women had less atherosclerosis than men, but this female advantage was lost with diabetes. Among those without clinical CAD, diabetes was associated with a global coronary disease burden and a prevalence of high-grade atherosclerosis similar to that observed among nondiabetic subjects with clinical CAD. CONCLUSIONS These findings provide mechanistic insights into the excess risk of clinical CAD among diabetic individuals, thereby supporting the need for aggressive prevention of atherosclerosis in all diabetic individuals, irrespective of clinical CAD symptoms.

Pulmonary Pressures and Death in Heart Failure: A Community Study

OBJECTIVES The purpose of this study was to determine among community patients with heart failure (HF) whether pulmonary artery systolic pressure (PASP) assessed by Doppler echocardiography was associated with death and improved risk prediction over established factors, using the integrated discrimination improvement and net reclassification improvement. BACKGROUND Although several studies have focused on idiopathic pulmonary arterial hypertension, less is known about pulmonary hypertension among patients with HF, particularly about its prognostic value in the community. METHODS Between 2003 and 2010, Olmsted County residents with HF prospectively underwent assessment of ejection fraction, diastolic function, and PASP by Doppler echocardiography. RESULTS PASP was recorded in 1,049 of 1,153 patients (mean age 76 ± 13; 51% women). Median PASP was 48 mm Hg (25th to 75th percentile: 37.0 to 58.0). There were 489 deaths after a follow-up of 2.7 ± 1.9 years. There was a strong positive graded association between PASP and mortality. Increasing PASP was associated with an increased risk of death (hazard ratio [HR]: 1.45, 95% confidence interval [CI]: 1.13 to 1.85 for tertile 2; HR: 2.07, 95% CI: 1.62 to 2.64 for tertile 3 vs. tertile 1), independently of age, sex, comorbidities, ejection fraction, and diastolic function. Adding PASP to models including these clinical characteristics resulted in an increase in the c-statistic from 0.704 to 0.742 (p = 0.007), an integrated discrimination improvement gain of 4.2% (p < 0.001), and a net reclassification improvement of 14.1% (p = 0.002), indicating that PASP improved prediction of death over traditional prognostic factors. All results were similar for cardiovascular death. CONCLUSIONS Among community patients with HF, PASP strongly predicts death and provides incremental and clinically relevant prognostic information independently of known predictors of outcomes.

Sudden Death After Myocardial Infarction

CONTEXT Sudden cardiac death after myocardial infarction (MI) has not been assessed recently in the community. Risk stratification for sudden cardiac death after MI commonly relies on baseline characteristics and little is known about the relationship between recurrent ischemia or heart failure and sudden cardiac death. OBJECTIVE To evaluate the risk of sudden cardiac death after MI and the impact of recurrent ischemia and heart failure on sudden cardiac death. DESIGN, SETTING, AND PARTICIPANTS Population-based surveillance study of 2997 residents (mean [SD] age, 67 [14] years; 59% were men) experiencing an MI in Olmsted County, Minnesota, between 1979 and 2005, and followed up through February 29, 2008. MAIN OUTCOME MEASURES Sudden cardiac death defined as out-of-hospital death due to coronary disease; and observed survival free of sudden cardiac death compared with that expected in Olmsted County, Minnesota. RESULTS During a median follow-up of 4.7 years (25th-75th percentile, 1.6-7.1 years), 1160 deaths occurred, 282 from sudden cardiac death (24%). The 30-day cumulative incidence of sudden cardiac death was 1.2% (95% confidence interval [CI], 0.8%-1.6%). Thereafter, the rate of sudden cardiac death was constant at 1.2% per year yielding a 5-year cumulative incidence of 6.9% (95% CI, 5.9%-7.9%). The 30-day incidence of sudden cardiac death was 4-fold higher than expected (standardized mortality ratio, 4.2; 95% CI, 2.9-5.8). The risk of sudden cardiac death has declined significantly over time (hazard ratio [HR], 0.62 [95% CI, 0.44-0.88] for MIs that occurred between 1997 and 2005 compared with between 1979 and 1987; P = .03). The recurrent events of ischemia (n = 842), heart failure (n = 365), or both (n = 873) occurred in 2080 patients. After adjustment for baseline characteristics, recurrent ischemia was not associated with sudden cardiac death (HR, 1.26 [95% CI, 0.96-1.65]; P = .09), while heart failure markedly increased the risk of sudden cardiac death (HR, 4.20 [95% CI, 3.10-5.69]; P < .001). CONCLUSIONS The risk of sudden cardiac death following MI in community practice has declined significantly over the past 30 years. Sudden cardiac death is independently associated with heart failure but not with recurrent ischemia.