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Limited information exists regarding the significance of dyspnea in patients who are unable to exercise and the contribution of myocardial ischemia to this symptom. To assess this, we evaluated results of dobutamine stress echocardiography (DSE) and long-term outcome of patients with dyspnea referred for DSE. We studied 6,376 consecutive patients who were unable to perform an exercise test and were referred for DSE. Patients were classified according to presenting symptoms and followed for 5.5 +/- 2.8 years. End points were cardiac ischemic events (myocardial infarction or revascularization), hospitalization for heart failure (HF), and death. Dobutamine stress echocardiogram was positive for ischemia in 19% of patients with dyspnea versus 24% (p = 0.002) of those with typical angina and 17% (p = 0.2) of asymptomatic patients. In multivariate analysis, risk of death was increased in dyspneic patients versus asymptomatic patients (hazard ratio [HR] 1.14, p = 0.02) and patients with chest pain (HR 1.20, p <0.001). Hospitalization for HF occurred more often in patients with dyspnea (HR 1.26, p = 0.05 vs asymptomatic; HR 1.24, p = 0.06 vs chest pain), especially in the subset without previous HF (HR 1.45, p = 0.006 vs chest pain). Risk of cardiac ischemic events in patients with dyspnea was similar versus asymptomatic patients (HR 0.92, p = 0.39) and decreased versus patients with chest pain (HR 0.70, p <0.001). In conclusion, in patients referred for DSE, dyspnea was associated with a poor outcome. This increased hazard seems not to be linked to myocardial ischemia, but instead to HF and death.

Aims: To estimate the incidence of dementia after the first atrial fibrillation (AF), and its impact on survival in a community-based cohort., Methods and Results: Olmsted County, Minnesota adult residents diagnosed with first AF during 1986-2000 were identified, and followed until 2004. The primary outcome was new detection of dementia. Interim stroke was censored in the analyses. Of 2837 subjects (71 +/- 15 years old) diagnosed with first AF and without any evidence of cognitive dysfunction or stroke at the time of AF onset, 299 were diagnosed with dementia during a median follow-up of 4.6 years [interquartile (IQR) range 1.5-7.9 years], and 1638 died. The Kaplan-Meier cumulative rate of dementia was 2.7% at 1 year and 10.5% at 5 years. After adjustment for age and sex, dementia was strongly related to advancing age [hazard ratio (HR)/10 years, 2.8; 95% confidence interval (CI), 2.5-3.2], but did not vary with sex (P = 0.52). The occurrence of post-AF dementia was associated with significantly increased mortality risk (HR 2.9; 95% CI 2.5-3.3), even after adjustment for multiple comorbidities, and did not vary with age (P = 0.75) or sex (P = 0.33)., Conclusion: Dementia appeared common following the diagnosis of first AF, and was associated with premature death.

Purpose: We aimed to determine the long-term, gender-specific incidence and mortality risk of coronary ischemic events after first atrial fibrillation (AF)., Methods: In this longitudinal cohort study, adult residents of Olmsted County, Minnesota, with an electrocardiogram-confirmed AF first documented in 1980 to 2000 and without prior coronary heart disease, were followed to 2004. The primary outcome was first coronary events (angina with angiographic confirmation, unstable angina, nonfatal myocardial infarction, or coronary death). Sex-specific incidence of coronary ischemic events and survival after development of such events were assessed using Cox proportional hazards modeling. Kaplan-Meier estimates of risks for coronary ischemic events were compared with those predicted by the Framingham equation., Results: Of the 2768 subjects (mean age 71 years, 48% were men), 463 (17%) had a first coronary event during a follow-up of 6.0+/-5.2 years. The unadjusted incidence was 31 per 1000 person-years, and there was no difference between men and women. The incidence was higher in men (hazard ratio 1.32, P=.004) after adjusting for age. The 10-year event estimates were 22% and 19% in men and women, respectively, by our Kaplan-Meier analyses, and 21% and 11%, respectively, by Framingham risk equation. The mortality risk after coronary events was higher in women (hazard ratio 2.99 vs 2.33; P=.044), even after multiple adjustment., Conclusions: First AF marks a high risk for new coronary ischemic events in both men and women. AF conferred additional risk for coronary events beyond conventional risk prediction in women only. The excess mortality risk associated with the development of coronary events was significantly greater in women.

Objectives: The purpose of this study was to assess the mortality trends of atrial fibrillation (AF) in a community., Background: Limited data exist regarding the mortality trends of patients diagnosed with first AF., Methods: A community-based cohort of adult residents of Olmsted County, Minnesota, who had electrocardiogram-confirmed first-documented AF in the years 1980 to 2000 were identified and followed to 2004 or death. The primary outcome was all-cause mortality., Results: Of a total of 4,618 residents (mean age 73 +/- 14 years) diagnosed with first AF, 3,085 died during a mean follow-up of 5.3 +/- 5.0 years. Relative to the age- and gender-matched general Minnesota population, the mortality risk was increased (p < 0.0001) with a hazard ratio (HR) of 9.62 (95% confidence interval [CI] 8.93 to 10.32) within the first 4 months and 1.66 (95% CI 1.59 to 1.73) thereafter. Cox proportional hazards modeling showed no change in overall age- and gender-adjusted mortality (HR for the year 2000 vs. 1980: 0.99; 95% CI 0.86 to 1.13; p = 0.84), even after adjustment for comorbidities. In secondary analyses, no changes in mortality were seen for early (within first 4 months) or late (after 4 months) mortality for the entire group or within the subgroup of patients who did not have cardiovascular disease at baseline., Conclusions: In this cohort of patients newly diagnosed with AF, mortality risk was high, especially within the first 4 months. There was no evidence for any significant changes over the 21 years in terms of overall mortality, early or late mortality, or mortality among patients without pre-existing cardiovascular disease.

Background: Limited data exist on trends in incidence of atrial fibrillation (AF). We assessed the community-based trends in AF incidence for 1980 to 2000 and provided prevalence projections to 2050., Methods and Results: The adult residents of Olmsted County, Minnesota, who had ECG-confirmed first AF in the period 1980 to 2000 (n=4618) were identified. Trends in age-adjusted incidence were determined and used to construct model-based prevalence estimates. The age- and sex-adjusted incidence of AF per 1000 person-years was 3.04 (95% CI, 2.78 to 3.31) in 1980 and 3.68 (95% CI, 3.42 to 3.95) in 2000. According to Poisson regression with adjustment for age and sex, incidence of AF increased significantly (P=0.014), with a relative increase of 12.6% (95% CI, 2.1 to 23.1) over 21 years. The increase in age-adjusted AF incidence did not differ between men and women (P=0.84). According to the US population projections by the US Census Bureau, the number of persons with AF is projected to be 12.1 million by 2050, assuming no further increase in age-adjusted incidence of AF, but 15.9 million if the increase in incidence continues., Conclusions: The age-adjusted incidence of AF increased significantly in Olmsted County during 1980 to 2000. Whether or not this rate of increase continues, the projected number of persons with AF for the United States will exceed 10 million by 2050, underscoring the urgent need for primary prevention strategies against AF development.

Aims: We sought to determine whether the incidence of and survival following congestive heart failure (CHF) in patients with atrial fibrillation (AF) have changed over time., Methods and Results: Olmsted County, Minnesota residents diagnosed with first AF during 1980-2000 were identified and followed in medical records to 2004. The trends of incidence and survival of CHF over time were assessed. Of the 3288 subjects (mean age 71+/-15 years) diagnosed with first AF and without CHF prior to or at AF diagnosis, 790 (24%) developed a first CHF during a mean follow-up of 6.1+/-5.2 years (unadjusted incidence, 44 per 1000 person years). Age- and sex-adjusted CHF incidence was unrelated to calendar year of AF diagnosis (P = 0.86). The age- and sex-adjusted mortality risk following CHF was higher than that in patients without CHF (hazard ratio 3.4, 95% confidence interval 3.1-3.8, P < 0.0001). There were no detectable changes over time with respect to the absolute (P = 0.94) or the relative (P = 0.68) mortality risk after CHF diagnosis., Conclusion: In this study spanning two decades, there appeared to have been no significant reduction in terms of the incidence and mortality risk of CHF following first AF diagnosis.

Objective: To determine the clinical importance of left atrial (LA) volume in the prediction of first ischemic stroke., Patients and Methods: This retrospective cohort study included randomly selected residents of Olmsted County, Minnesota, aged 65 years or older, who had undergone transthoracic echocardiography at least once at the Mayo Clinic in Rochester, Minn, between January 1, 1990, and December 31, 1998, were in sinus rhythm, and had no history of stroke, transient ischemic attack, atrial fibrillation, or valvular heart disease. Patients were monitored through medical records for first ischemic stroke or death., Results: Of 1554 residents (59% women) aged 75+/-7 years, 92 (6%) had experienced at least 1 ischemic stroke over 4.3+/-2.7 years (incident stroke rate, 1.4 per 100 person-years). Left atrial volume of 32 mL/m2 or greater (hazard ratio [HR], 1.63; confidence interval [CI], 1.08-2.46) was independent of age (HR, 1.04; CI, 1.02-1.07), diabetes (HR, 1.91; CI, 1.07-3.41), myocardial infarction (HR, 1.64; CI, 1.01-2.64), and hyperlipidemia (HR, 1.55; CI, 1.01-2.37) for the prediction of first ischemic stroke. When quartiles of LA dimension were plotted against quartiles of indexed LA volume, a stepwise increase in risk with each quartile increment was evident only for indexed LA volume. Also, an LA volume of 32 mL/m2 or greater was associated with an increased mortality risk (HR, 1.30; CI, 1.09-1.56), independent of age, sex, and stroke status., Conclusions: In our elderly cohort with no prior atrial fibrillation, LA volume was independently predictive of first ischemic stroke, incremental to age, diabetes, myocardial infarction, and hyperlipidemia. It was also an independent predictor of death.

Objectives: We sought to determine if echocardiography enhances prediction of first age-related cardiovascular events., Background: Whether echocardiographic assessment improves risk stratification for first cardiovascular events is not well known., Methods: This retrospective cohort study included randomly selected residents of Olmsted County, Minnesota, age >/=65 years, who had >/=1 transthoracic echocardiograms at the Mayo Clinic between 1990 and 1998, in sinus rhythm, without valvular or congenital heart disease, and followed through medical records for first myocardial infarction (MI), coronary revascularization, atrial fibrillation (AF), congestive heart failure (CHF), transient ischemic attack (TIA), stroke, or cardiovascular death. Patients were excluded if they had any of these events before the baseline echocardiogram., Results: Of 1,160 patients (age 75 +/- 7 years; 746 women) followed for a mean of 3.8 +/- 2.7 years, 333 (29%) first events occurred (70 AF, 67 coronary revascularization procedures, 65 CHF, 48 MI, 38 stroke, 25 TIA, and 20 cardiovascular deaths). In a multivariate model, age (p < 0.001), male gender (p < 0.001), diabetes mellitus (p = 0.005), systemic hypertension (p < 0.001), left atrial volume/body surface area >/=32 ml/m(2) (p = 0.003), left ventricular (LV) mass/height >/=120 g/m (p = 0.014), LV systolic dysfunction (p < 0.001), and LV diastolic dysfunction (p = 0.029) were independent predictors. A risk-scoring algorithm was developed and validated for the prediction of first events. The five-year event-free survival was 90%, 74%, and 50% for low-, medium-, and high-risk groups, respectively., Conclusions: Echocardiography enhanced prediction of first cardiovascular events in this referral-based elderly cohort. Its role in risk stratification for primary prevention of these events in the community warrants further investigations.

Objectives: We sought evidence of a change in the prevalence of atrial fibrillation (AF) over a 30-year period among residents of Rochester, Minnesota., Background: Atrial fibrillation is increasingly encountered in clinical practice, but there is limited data on secular trends of AF over time., Methods: Within a longitudinal case-control study of ischemic stroke, the prevalence of AF and of selected comorbid conditions among incident stroke cases and age- and gender-matched controls between 1960 and 1989 was determined., Results: The mean age +/- standard deviation for the 1,871 stroke cases (45% men) and matched controls was 75 +/- 11 years. For cases, age-adjusted estimates of AF prevalence for 1960 to 1969, 1970 to 1979, and 1980 to 1989 were 11%, 13%, and 16%, respectively, for men, and 13%, 16%, and 20% for women. For controls, the rates were 5%, 8%, and 12%, respectively, for men, and 4%, 6%, and 8% for women. Increasing AF prevalence was associated with increasing age (doubling of odds per decade of age in both cases and controls) and calendar time adjusted for age and gender (cases: odds ratio [OR] per 5 years 1.13, 95% confidence interval [CI], 1.05 to 1.22; controls: OR per 5 years 1.24, 95% CI 1.12 to 1.37). The rates of increase with calendar time were significant for cases (p = 0.001) and controls (p < 0.001) and comparable between the genders., Conclusions: The prevalence of AF increased significantly in ischemic stroke patients and their controls from 1960 to 1989 in Rochester, Minnesota, independent of age and gender. The rate of increase did not differ significantly between men and women.

Objectives: To evaluate consecutive therapeutic echocardiographically (echo)-guided pericardiocenteses performed at Mayo Clinic, Rochester, Minn, from 1979 to 2000 and to determine whether patient profiles, practice patterns, and outcomes have changed over time., Patients and Methods: Consecutive echo-guided pericardiocenteses performed between February 1, 1979, and January 31, 2000, for treatment of clinically significant pericardial effusions were identified in the Mayo Clinic Echocardiographic-guided Pericardiocentesis Registry. The medical records of these patients were examined, and a follow-up survey was conducted. Clinical profiles, echocardiographic findings, procedural details, and outcomes were determined for 3 periods: February 1, 1979, through January 31, 1986; February 1, 1986, through January 31, 1993; and February 1, 1993, through January 31, 2000., Results: During the 21-year study period, 1127 therapeutic echo-guided pericardiocenteses were performed in 977 patients. The mean +/- SD age at pericardiocentesis increased from 49+/-14 years in period 1 to 57+/-14 years in period 3. In recent years, cardiothoracic surgery replaced malignancy as the leading cause of an effusion requiring pericardiocentesis and together with malignancy and perforation from catheter-based procedures accounted for nearly 70% of all pericardiocenteses performed. The procedural success rate was 97% overall, with a total complication rate of 4.7% (major, 1.2%; minor, 3.5%). These rates did not change significantly over time. The use of a pericardial catheter for extended drainage increased from 23% in period 1 to 75% in period 3 (P<.001), whereas rates of effusion recurrence and pericardial surgery decreased significantly (P<.001)., Conclusions: The profile of patients presenting with clinically significant pericardial effusion has changed over time. Increasing numbers of older patients and those who have undergone cardiothoracic surgery or catheter-based procedures develop effusions that can be rapidly, safely, and effectively managed with echo-guided pericardiocentesis. Extended drainage with use of a pericardial catheter has become standard practice, and concomitantly, recurrence rates and need for surgical management have decreased considerably.