Alexis L. Beatty

Using mobile technology for cardiac rehabilitation: a review and framework for development and evaluation.

Ischemic heart disease (IHD) is the leading cause of death in the United States.[1][1] Cardiac rehabilitation is an evidence-based, cost-effective, multidisciplinary program of individual patient risk factor assessment and management, exercise training, and psychosocial support for patients with

Six-minute walk test as a prognostic tool in stable coronary heart disease: data from the Heart and Soul Study

BACKGROUND The prognostic value of the 6-minute walk test (6MWT) in patients with stable coronary heart disease is unknown. We sought to determine whether the 6MWT predicted cardiovascular events in ambulatory patients with coronary heart disease. METHODS We measured 6MWT distance and treadmill exercise capacity in 556 outpatients with stable coronary heart disease from September 11, 2000, through December 20, 2002. Participants were followed up for a median of 8.0 years for cardiovascular events (heart failure, myocardial infarction, and death). RESULTS Cardiovascular events occurred in 218 of 556 participants (39.2%). Patients in the lowest quartile of 6MWT distance (87-419 m) had 4 times the rate of events as those in the highest quartile (544-837 m) (unadjusted hazard ratio, 4.29; 95% CI, 2.83-6.53; P < .001). Each SD decrease in 6MWT distance (104 m) was associated with a 55% higher rate of cardiovascular events (age-adjusted hazard ratio, 1.55; 95% CI, 1.35-1.78). After adjustment for traditional risk factors and cardiac disease severity measures (ejection fraction, inducible ischemia, diastolic dysfunction, amino-terminal portion of the prohormone of brain-type natriuretic peptide, and C-reactive protein), each SD decrease in 6MWT was associated with a 30% higher rate of cardiovascular events (hazard ratio, 1.30; 95% CI, 1.10-1.53). When added to traditional risk factors, the 6MWT resulted in category-free net reclassification improvement of 39% (95% CI, 19%-60%). The discriminative ability of the 6MWT was similar to that of treadmill exercise capacity for predicting cardiovascular events (C statistics both 0.72; P = .29). CONCLUSIONS Distance walked on the 6MWT predicted cardiovascular events in patients with stable coronary heart disease. The addition of a simple 6MWT to traditional risk factors improved risk prediction and was comparable with treadmill exercise capacity.

High-Sensitivity Cardiac Troponin T Levels and Secondary Events in Outpatients With Coronary Heart Disease From the Heart and Soul Study

IMPORTANCE Levels of high-sensitivity cardiac troponin T (hs-cTnT) predict secondary cardiovascular events in patients with stable coronary heart disease. OBJECTIVES To determine the association of hs-cTnT levels with structural and functional measures of heart disease and the extent to which these measures explain the relationship between hs-cTnT and secondary events. DESIGN We measured serum concentrations of hs-cTnT and performed exercise treadmill testing with stress echocardiography in a prospective cohort study of outpatients with coronary heart disease who were enrolled from September 11, 2000, through December 20, 2002, and followed up for a median of 8.2 years. SETTING Twelve outpatient clinics in the San Francisco Bay Area. PARTICIPANTS Nine hundred eighty-four patients with stable coronary heart disease. MAIN OUTCOMES AND MEASURES Cardiovascular events (myocardial infarction, heart failure, or cardiovascular death), determined by review of medical records and death certificates. RESULTS Of 984 participants, 794 (80.7%) had detectable hs-cTnT levels. At baseline, higher hs-cTnT levels were associated with greater inducible ischemia and worse left ventricular ejection fraction, left atrial function, diastolic function, left ventricular mass, and treadmill exercise capacity. During follow-up, 317 participants (32.2%) experienced a cardiovascular event. After adjustment for clinical risk factors, baseline cardiac structure and function, and other biomarkers (N-terminal portion of the prohormone of brain-type natriuretic peptide and C-reactive protein levels), each doubling in hs-cTnT level remained associated with a 37% higher rate of cardiovascular events (hazard ratio, 1.37 [95% CI, 1.14-1.65]; P = .001). CONCLUSIONS AND RELEVANCE In outpatients with stable coronary heart disease, higher hs-cTnT levels were associated with multiple abnormalities of cardiac structure and function but remained independently predictive of secondary events. These findings suggest that hs-cTnT levels may detect an element of risk that is not captured by existing measures of cardiac disease severity.

Adiponectin is associated with increased mortality and heart failure in patients with stable ischemic heart disease: data from the Heart and Soul Study.

OBJECTIVE Serum adiponectin protects against incident ischemic heart disease (IHD). However, in patients with existing IHD, higher adiponectin levels are paradoxically associated with worse outcomes. We investigated this paradox by evaluating the relationship between adiponectin and cardiovascular events in patients with existing IHD. METHODS We measured total serum adiponectin and cardiac disease severity by stress echocardiography in 981 outpatients with stable IHD who were recruited for the Heart and Soul Study between September 2000 and December 2002. Subsequent heart failure hospitalizations, myocardial infarction, and death were recorded. RESULTS During an average of 7.1 years of follow-up, patients with adiponectin levels in the highest quartile were more likely than those in the lowest quartile to be hospitalized for heart failure (23% vs. 13%; demographics-adjusted hazard ratio (HR) 1.63, 95% confidence interval (CI) 1.04-2.56, p=0.03) or die (49% vs. 31%; HR 1.67, 95% CI 1.24-2.26, p<0.008), but not more likely to have a myocardial infarction (12% vs. 17%; HR 0.64, 95% CI 0.38-1.06, p=0.08). The combined outcome of myocardial infarction, heart failure, or death occurred in 56% (136/245) of participants in the highest quartile of adiponectin vs. 38% (94/246) of participants in the lowest quartile (HR 1.54, 95% CI 1.31-2.21, p<0.002). Adjustment for left ventricular ejection fraction, diastolic dysfunction, inducible ischemia, C-reactive protein, and NT-proBNP attenuated the association between higher adiponectin and increased risk of subsequent events (HR 1.43, 95% CI 0.98-2.09, p=0.06). CONCLUSIONS Higher concentrations of adiponectin were associated with heart failure and mortality among patients with existing IHD.

Association of growth differentiation factor 11/8, putative anti-ageing factor, with cardiovascular outcomes and overall mortality in humans: analysis of the Heart and Soul and HUNT3 cohorts

AIMS Growth differentiation factor 11 and/or its homologue growth differentiation factor 8 (GDF11/8) reverses age-related cardiac hypertrophy and vascular ageing in mice. We investigated whether GDF11/8 associates with cardiovascular outcomes, left ventricular hypertrophy (LVH), or age in humans. METHODS AND RESULTS We measured plasma GDF11/8 levels in 928 participants with stable ischaemic heart disease in the Heart and Soul study. We adjudicated heart failure hospitalization, stroke, myocardial infarction, death, and their composite endpoint. Left ventricular hypertrophy was evaluated by echocardiography. We used multivariable Cox proportional hazards models to compare rates of cardiovascular events and death across GDF11/8 quartiles and logistic regression models to evaluate the association between GDF11/8 and LVH. Four hundred and fifty participants (48.5%) experienced a cardiovascular event or death during 8.9 years of follow-up. The adjusted risk of the composite endpoint was lower in the highest compared with the lowest GDF11/8 quartile [hazard ratio (HR), 0.45; 95% confidence interval (CI), 0.33-0.60; P < 0.001]. We replicated this relationship of GDF11/8 to adverse events in 971 participants in the HUNT3 cohort (adjusted HR, 0.34; 95% CI, 0.23-0.51; P < 0.001). Left ventricular hypertrophy was present in 368 participants (39.7%) at baseline. Participants in the highest quartile of GDF11/8 were less likely to have LVH than those in the lowest quartile (adjusted OR, 0.55; 95% CI, 0.35-0.86; P = 0.009). GDF11/8 levels were lower in older individuals (P < 0.001). CONCLUSION In patients with stable ischaemic heart disease, higher GDF11/8 levels are associated with lower risk of cardiovascular events and death. Our findings suggest that GDF11/8 has similar cardioprotective properties in humans to those demonstrated in mice.

Mobile Phone Interventions for the Secondary Prevention of Cardiovascular Disease.

Mobile health in the form of text messaging and mobile applications provides an innovative and effective approach to promote prevention and management of cardiovascular disease (CVD); however, the magnitude of these effects is unclear. Through a comprehensive search of databases from 2002-2016, we conducted a quantitative systematic review. The selected studies were critically evaluated to extract and summarize pertinent characteristics and outcomes. A large majority of studies (22 of 28, 79%) demonstrated text messaging, mobile applications, and telemonitoring via mobile phones were effective in improving outcomes. Some key factors associated with successful interventions included personalized messages with tailored advice, greater engagement (2-way text messaging, higher frequency of messages), and use of multiple modalities. Overall, text messaging appears more effective than smartphone-based interventions. Incorporating principles of behavioral activation will help promote and sustain healthy lifestyle behaviors in patients with CVD that result in improved clinical outcomes.

Traditional Risk Factors Versus Biomarkers for Prediction of Secondary Events in Patients With Stable Coronary Heart Disease: From the Heart and Soul Study

Background Patients with stable coronary heart disease (CHD) have widely varying prognoses and treatment options. Validated models for risk stratification of patients with CHD are needed. We sought to evaluate traditional and novel risk factors as predictors of secondary cardiovascular (CV) events, and to develop a prediction model that could be used to risk stratify patients with stable CHD. Methods and Results We used independent derivation (912 participants in the Heart and Soul Study) and validation (2876 participants in the PEACE trial) cohorts of patients with stable CHD to develop a risk prediction model using Cox proportional hazards models. The outcome was CV events, defined as myocardial infarction, stroke, or CV death. The annual rate of CV events was 3.4% in the derivation cohort and 2.2% in the validation cohort. With the exception of smoking, traditional risk factors (including age, sex, body mass index, hypertension, dyslipidemia, and diabetes) did not emerge as the top predictors of secondary CV events. The top 4 predictors of secondary events were the following: N-terminal pro-type brain natriuretic peptide, high-sensitivity cardiac troponin T, urinary albumin:creatinine ratio, and current smoking. The 5-year C-index for this 4-predictor model was 0.73 in the derivation cohort and 0.65 in the validation cohort. As compared with variables in the Framingham secondary events model, the Heart and Soul risk model resulted in net reclassification improvement of 0.47 (95% CI 0.25 to 0.73) in the derivation cohort and 0.18 (95% CI 0.01 to 0.40) in the validation cohort. Conclusions Novel risk factors are superior to traditional risk factors for predicting 5-year risk of secondary events in patients with stable CHD.

Trends in Referral to Cardiac Rehabilitation After Myocardial Infarction: Data From the National Cardiovascular Data Registry 2007 to 2012

To the Editor: Cardiac rehabilitation (CR) is a guideline-recommended therapy that reduces mortality after acute myocardial infarction (MI) [(1)][1]. However, it is notoriously underutilized. Between 2000 and 2007, only 56% of eligible patients were referred to CR [(1,2)][1]. In 2007, professional

B-type Natriuretic Peptides for the Prediction of Cardiovascular Events in Patients With Stable Coronary Heart Disease: The Heart and Soul Study

Background Brain‐type natriuretic peptide (BNP) and the amino‐terminal fragment of its prohormone (NT‐proBNP) are known predictors of cardiovascular outcomes in patients with coronary heart disease; however, the relative prognostic value of these 2 biomarkers for secondary events remains unclear. Methods and Results In 983 participants with stable coronary heart disease, we evaluated the association of BNP and NT‐proBNP with time to hospitalization for heart failure, nonfatal myocardial infarction, stroke or transient ischemic attack, cardiovascular death, and combined major adverse cardiovascular events (MACE). During an average follow‐up of 6.5±3.3 years, both BNP and NT‐proBNP were associated with increased risk of MACE in a multivariable‐adjusted model (hazard ratio per standard deviation of log BNP: 1.58; 95% CI: 1.32 to 1.89; hazard ratio per standard deviation of log NT‐proBNP: 1.84; 95% CI: 1.52 to 2.24). When added to traditional risk factors, NT‐proBNP predicted MACE better than BNP (C statistic: 0.76 versus 0.72, P<0.001). Similarly, the addition of NT‐proBNP resulted in a greater net reclassification improvement for predicting MACE than the addition of BNP (65% for NT‐proBNP, 56% for BNP). Conclusions Both BNP and NT‐proBNP were significant predictors of MACE in stable coronary heart disease; however, NT‐proBNP was superior to BNP for net risk reclassification for MACE.

Associations between respiratory illnesses and secondhand smoke exposure in flight attendants: A cross-sectional analysis of the Flight Attendant Medical Research Institute Survey

BackgroundSecondhand tobacco smoke (SHS) is associated with increased risk of respiratory illness, cancer, and cardiovascular disease. Prior to smoking bans on airlines in the late 1980s, flight attendants were exposed to a significant amount of SHS. In the present study, we examine associations between flight attendant SHS exposure and development of respiratory illnesses and cardiovascular disease.MethodsBetween December 2006 and October 2010, three hundred sixty-two flight attendants completed an online questionnaire with information regarding experience as a flight attendant, medical history, smoking history, and SHS exposure. Rates of illnesses in flight attendants were compared with an age and smoking history matched population sample from NHANES 2005-2006. Logistic regression analysis was used to examine the association of reported medical conditions and pre-ban years of exposure.ResultsCompared with the sample from NHANES 2005-2006, flight attendants had increased prevalence of chronic bronchitis (11.7% vs. 7.2%, p < 0.05), emphysema/COPD (3.2% vs. 0.9%, p < 0.03), and sinus problems (31.5% vs. 20.9%, p < 0.002), despite a lower prevalence of medical illnesses including high blood pressure, diabetes, high cholesterol, heart failure, cancer, and thyroid disease. Amongst flight attendants who reported never smoking over their lifetimes, there was not a significant association between years of service as a flight attendant in the pre-smoking ban era and illnesses. However, in this same group, there was a significantly increased risk of daily symptoms (vs. no symptoms) of nasal congestion, throat, or eye irritation per 10-year increase of years of service as a flight attendant prior to the smoking ban (OR 2.14, 95% CI 1.41 - 3.24).ConclusionsFlight attendants experience increased rates of respiratory illnesses compared to a population sample. The frequency of symptoms of nasal congestion, throat or eye irritation is associated with occupational SHS exposure in the pre-smoking ban era.