Lindsay G Smith

Sudden cardiac death in heart failure patients with preserved ejection fraction

BACKGROUND Whereas sudden cardiac death (SCD) risk has been recognized in heart failure (HF) patients with reduced ejection fraction (HFrEF), less is known about SCD risk in HF patients with preserved EF (HFpEF). We examined the incidence and predictors of SCD in HFpEF in a large population sample. METHODS AND RESULTS Medical records of patients discharged with a primary diagnosis of HF from hospitals in Minneapolis-St Paul in 1995 and 2000 were abstracted. HFpEF was defined as EF ≥ 45%. SCD was defined as cardiac arrest or out-of-hospital death due to coronary heart disease (CHD) on death certificates. A total of 2,203 patients (age 70 ± 11 years, 53% male) were included. The 787 patients (36%) with HFpEF were older, more often female and more likely to have hypertension than the 1,416 (64%) with HFrEF. All-cause mortality (52% vs 58%; P = .01) and SCD (6% vs 14%; P < .0001) rates were lower in HFpEF than in HFrEF 5 years after hospital discharge. Age, sex, CHD, and length of index hospitalization were the only independent predictors of SCD in HFpEF. CONCLUSIONS Incidence of SCD in HFpEF is lower than in HFrEF. Present markers of SCD in HFpEF are sparse and insufficient to identify the patient at risk.

The Effect of Changing Diagnostic Algorithms on Acute Myocardial Infarction Rates

PURPOSE Population rates of acute myocardial infarction (AMI) are changing. Consistent case definitions to evaluate these trends and make comparisons are essential. The World Health Organization (WHO) AMI diagnostic algorithm and clinical judgments were the standards for classification. However, in recent years, five new algorithms, to include diagnostic advances, are advocated by professional organizations. This study compares AMI rates derived from six algorithms and the impact of troponins on those rates. METHODS The authors use the population-based Minnesota Heart Survey hospital data in 1995 and 2001 to compare six published diagnostic algorithms and the impact of troponins. RESULTS In 1995 differences in AMI rates between algorithms ranged from 281/100,000 to 440/100,000 for men and 98/100,000 to 139/100,000 for women. The use of troponin, a more sensitive biomarker, adds to the differences by increasing eligible cases. Using 2001 data in patients where creatine kinase and troponin were simultaneously measured, a 64% and 95% increase in AMI rates among men and women, respectively, was observed. CONCLUSIONS Accurate and consistent AMI definitions are crucial for clinical trials, epidemiology and public health research. Demonstrated here is the sensitivity of AMI rates to changing case definitions and the biomarker troponin.

International comparison of treatment and long-term outcomes for acute myocardial infarction in the elderly: Minneapolis/St. Paul, MN, USA and Göteborg, Sweden

AIMS International studies provide an opportunity to compare treatment approaches and outcomes. The present study compares elderly hospitalized acute myocardial infarction (AMI) patients in Minneapolis/St. Paul, USA (MSP) and Göteborg, Sweden (GB). METHODS AND RESULTS A population-based sample of hospitalized AMI (ICD-9 410) patients aged ≥75 in MSP and GB in 2001-02 was abstracted by trained nurses. Mortality was ascertained from medical records and death certificates. Demographics, cardiovascular procedures, and prescription medications were compared using sex-specific generalized linear models. Adjusted hazard ratios (HR) were calculated with Cox regression. In MSP 839 (387 men, 452 women) and in GB 564 (275 men, 289 women) patients were identified. Age was similar (men: MSP 83 ± 7, GB 82 ± 5; women: MSP 84 ± 6, GB 84 ± 6) yet MSP patients had more previous cardiovascular comorbidities and procedures (PCI/CABG). Guideline-based medication use was high in both locations. MSP patients were significantly more likely to undergo PCI (men: MSP 33%, GB 7%; women: MSP 30%, GB 7%). Survival at 7.5 years was 27.8% among MSP patients (men: 26.6%, women: 28.8%) and 17.2% among GB patients (men: 17.5%, women: 17.0%). After adjustment for baseline characteristics and guideline-based therapies, survival was higher among MSP men [HR: 0.66, 95% confidence interval (CI): 0.50-0.88] and women (HR: 0.49, 95% CI: 0.36-0.67) compared with GB. CONCLUSION In MSP and GB, guideline-based therapy use was high. However, PCI use was markedly higher in MSP. Long-term survival was better among elderly men and women in MSP compared with GB possibly related to greater utilization of PCI.

Are the results of a regional ST-elevation myocardial infarction system reproducible?

Primary percutaneous coronary intervention (PCI) is the preferred reperfusion method in patients with ST-elevation myocardial infarction (STEMI) if it can be performed in a timely manner in high-volume centers. Regional STEMI networks improve timely access to PCI but are frequently criticized for being single center. To determine if results of regional STEMI systems could be replicated and achieve similar outcomes in 2 separate geographic regions, we examined the prospective databases of 2 large regional STEMI networks that use identical standardized protocols and integrated transfer systems. The Minneapolis Heart Institute (MHI) database included 2,266 patients with STEMI from 31 hospitals (498 at the PCI hospital, 1,033 transferred from 11 hospitals <60 miles away, and 735 transferred from 19 hospitals 60 to 210 miles away). The Iowa Heart Center (IHC) database included 1,206 patients with STEMI from 24 hospitals (710 at the PCI hospital, 266 transferred from 10 hospitals <60 miles away, and 230 transferred from 13 hospitals 60 to 120 miles away). Median total door-to-balloon times for the PCI hospital, zone 1, and zone 2 patients were 64, 95, and 123 minutes for the MHI and 59, 102, and 136 for the IHC (p <0.05 for each comparison between MHI and IHC). Overall in-hospital, 30-day, and 1-year mortalities was 4.8%, 5.4%, and 8.0% respectively (p = NS for each comparison between MHI and IHC). In conclusion, the use of identical protocols in 2 large regional STEMI systems in geographically separate locations produced nearly identical outcomes, adding to evidence that regional STEMI centers expand timely access to PCI.

Height and risk of incident intraparenchymal hemorrhage: Atherosclerosis Risk in Communities and Cardiovascular Health study cohorts.

BACKGROUND Height is inversely associated with incident coronary disease and total stroke, but few studies have examined the association between height and intraparenchymal hemorrhage (IPH). We hypothesized that height would be inversely associated with incident IPH in the combined cohorts of the Atherosclerosis Risk in Communities Study and the Cardiovascular Health Study. METHODS Data on Caucasian and African American participants were used to estimate the association of height at baseline with incident IPH verified by clinician review of medical records and imaging reports. Sex-specific Cox proportional hazards regression models were used to calculate hazard ratios. RESULTS A total of 20,983 participants initially free of stroke (11,788 women and 9195 men) were followed for an average of 15.9 years (standard deviation [SD] 5.1 years). Incident IPH occurred in 115 women and 73 men. Sex, but not age, race, study, or blood pressure, modified the association (P = .03). After adjustment for risk factors (age, systolic blood pressure, triglycerides, low-density lipoprotein cholesterol, fibrinogen, and race), among women, height was significantly inversely associated with incident IPH (hazard ratio [HR] per SD [6.3 cm] was 0.81; 95% confidence interval [CI] 0.66-0.99; P = .04). The HR for tertile 3 vs 1 in women was 0.63 (95% CI 0.37-1.08). Among men, height was not linearly associated with incident IPH (HR per SD [6.7 cm] was 1.09; 95% CI 0.84-1.40; P = .52). CONCLUSIONS This large prospective study provides evidence that shorter height may be a risk factor for incident IPH in women.

INCIDENCE AND PREDICTORS OF SUDDEN CARDIAC DEATH IN COMMUNITY-BASED HEART FAILURE PATIENTS WITH PRESERVED EJECTION FRACTION: THE MINNESOTA HEART SURVEY

Whereas sudden cardiac death (SCD) is a well-studied mode of death in patients (pts) with heart failure (HF) and reduced ejection fraction (HFrEF), little is known about the risk of SCD in pts with HF and preserved EF (HFpEF). The objective of this study was to compare the incidence and predictors