Differential clinical prognostic classifications in dilated and ischemic advanced heart failure: the EPICAL study

Generalizability of Cardiovascular Disease Clinical Prediction Models: 158 Independent External Validations of 104 Unique Models

Background:

While clinical prediction models (CPMs) are used increasingly commonly to guide patient care, the performance and clinical utility of these CPMs in new patient cohorts is poorly understood.

Methods:

We performed 158 external validations of 104 unique CPMs across 3 domains of cardiovascular disease (primary prevention, acute coronary syndrome, and heart failure). Validations were performed in publicly available clinical trial cohorts and model performance was assessed using measures of discrimination, calibration, and net benefit. To explore potential reasons for poor model performance, CPM-clinical trial cohort pairs were stratified based on relatedness, a domain-specific set of characteristics to qualitatively grade the similarity of derivation and validation patient populations. We also examined the model-based C-statistic to assess whether changes in discrimination were because of differences in case-mix between the derivation and validation samples. The impact of model updating on model performance was also assessed.

Results:

Discrimination decreased significantly between model derivation (0.76 [interquartile range 0.73–0.78]) and validation (0.64 [interquartile range 0.60–0.67], P<0.001), but approximately half of this decrease was because of narrower case-mix in the validation samples. CPMs had better discrimination when tested in related compared with distantly related trial cohorts. Calibration slope was also significantly higher in related trial cohorts (0.77 [interquartile range, 0.59–0.90]) than distantly related cohorts (0.59 [interquartile range 0.43–0.73], P=0.001). When considering the full range of possible decision thresholds between half and twice the outcome incidence, 91% of models had a risk of harm (net benefit below default strategy) at some threshold; this risk could be reduced substantially via updating model intercept, calibration slope, or complete re-estimation.

Conclusions:

There are significant decreases in model performance when applying cardiovascular disease CPMs to new patient populations, resulting in substantial risk of harm. Model updating can mitigate these risks. Care should be taken when using CPMs to guide clinical decision-making.

Time-ordered dysregulated ceRNA networks reveal disease progression and diagnostic biomarkers in ischemic and dilated cardiomyopathy

Ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM) are the two main causes of heart failure (HF). Despite similar clinical characteristics and common “HF pathways”, ICM and DCM are expected to have different personalized treatment strategies. The underlying mechanisms of ICM and DCM have yet to be fully elucidated. The present study developed a novel computational method for identifying dysregulated long noncoding RNA (lncRNA)–microRNA (miRNA)–mRNA competing endogenous RNA (ceRNA) triplets. Time-ordered dysregulated ceRNA networks were subsequently constructed to reveal the possible disease progression of ICM and DCM based on the method. Biological functional analysis indicated that ICM and DCM had similar features during myocardial remodeling, whereas their characteristics differed during progression. Specifically, disturbance of myocardial energy metabolism may be the main characteristic during DCM progression, whereas early inflammation and response to oxygen are the characteristics that may be specific to ICM. In addition, several panels of diagnostic biomarkers for differentiating non-heart failure (NF) and ICM (NF-ICM), NF-DCM, and ICM-DCM were identified. Our study reveals biological differences during ICM and DCM progression and provides potential diagnostic biomarkers for ICM and DCM.

Plasma Metabolomic Profiles Differentiate Patients With Dilated Cardiomyopathy and Ischemic Cardiomyopathy

Dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM) are common causes of heart failure (HF). Though they share similar clinical characteristics, their differential effects on cardiovascular metabolomics have yet to be elucidated. In this study, we applied a comprehensive metabolomics platform to plasma samples of HF patients with different etiology (38 patients with DCM and 18 patients with ICM) and 20 healthy controls. Significant differences in metabolomics profiling were shown among two cardiomyopathy groups and healthy controls. Two hundred thirty three dysregulated metabolites were identified between DCM vs. healthy controls, and 204 dysregulated metabolites between ICM patients and healthy controls. They have 140 metabolites in common, with fold-changes in the same direction in both groups. Pathway analysis found the commonalities of HF pathways as well as disease-specific metabolic signatures. In addition, we found that a combination panel of 6 metabolites including 1-pyrroline-2-carboxylate, norvaline, lysophosphatidylinositol (16:0/0:0), phosphatidylglycerol (6:0/8:0), fatty acid esters of hydroxy fatty acid (24:1), and phosphatidylcholine (18:0/18:3) may have the potential to differentiate patients with DCM and ICM.

Transcriptome analysis of human heart failure reveals dysregulated cell adhesion in dilated cardiomyopathy and activated immune pathways in ischemic heart failure

Background

Current heart failure (HF) treatment is based on targeting symptoms and left ventricle dysfunction severity, relying on a common HF pathway paradigm to justify common treatments for HF patients. This common strategy may belie an incomplete understanding of heterogeneous underlying mechanisms and could be a barrier to more precise treatments. We hypothesized we could use RNA-sequencing (RNA-seq) in human heart tissue to delineate HF etiology-specific gene expression signatures.

Results

RNA-seq from 64 human left ventricular samples: 37 dilated (DCM), 13 ischemic (ICM), and 14 non-failing (NF). Using a multi-analytic approach including covariate adjustment for age and sex, differentially expressed genes (DEGs) were identified characterizing HF and disease-specific expression. Pathway analysis investigated enrichment for biologically relevant pathways and functions. DCM vs NF and ICM vs NF had shared HF-DEGs that were enriched for the fetal gene program and mitochondrial dysfunction. DCM-specific DEGs were enriched for cell-cell and cell-matrix adhesion pathways. ICM-specific DEGs were enriched for cytoskeletal and immune pathway activation. Using the ICM and DCM DEG signatures from our data we were able to correctly classify the phenotypes of 24/31 ICM and 32/36 DCM samples from publicly available replication datasets.

Conclusions

Our results demonstrate the commonality of mitochondrial dysfunction in end-stage HF but more importantly reveal key etiology-specific signatures. Dysfunctional cell-cell and cell-matrix adhesion signatures typified DCM whereas signals related to immune and fibrotic responses were seen in ICM. These findings suggest that transcriptome signatures may distinguish end-stage heart failure, shedding light on underlying biological differences between ICM and DCM.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-5213-9) contains supplementary material, which is available to authorized users.

Reasons why patients suffering from chronic heart failure at very low risk for mortality die

BACKGROUND

A proper prognostic stratification is crucial for organizing an effective clinical management and treatment decision-making in patients with chronic heart failure (CHF). In this study, we selected and characterized a sub-group of CHF patients at very low risk for death aiming to assess predictors of death in subjects with an expected probability of 1-year mortality near to 5%.

METHODS

We used the Cardiac and Comorbid Conditions HF (3C-HF) Score to identify CHF patients with the best mid-term prognosis. We selected patients belonging to the lowest quartile of 3C-HF score (≤9 points).

RESULTS

We recruited 1777 consecutive CHF patients at 3 Italian Cardiology Units (age 76±10years, 43% female, 32% with preserved ejection fraction). Subjects belonging to the lowest quartile of 3C-HF score were 609. During a median follow-up of 21 [12-40] months, 48 of these patients (8%) died, and 561 (92%) survived. The variables that contributed to death prediction by Cox regression multivariate analysis were older age (HR 1.03[CI 1.00-1.07]; p=0.04), male gender (HR 2.93[CI 1.50-5.51]; p=0.002) and a higher degree of renal dysfunction (HR 0.96[CI 0.94-0.98]; p<0.001).

CONCLUSIONS

The prognostic stratification of CHF patients by 3C-HF score allows one to select patients at different outcome and to identify the factors associated with death in outliers with a very low mortality risk at mid-term follow-up. The reasons why these patients do not outlive the matching part of subjects who expectedly survive are related to a declined renal function and unmodifiable conditions including older age and male gender.

Reasons why patients suffering from chronic heart failure at very high risk for death survive

BACKGROUND

An accurate prognostic stratification is essential for optimizing the clinical management and treatment decision-making of patients with chronic heart failure (HF). Among the best available models, we used the Cardiac and Comorbid Conditions HF (3C-HF) Score, to predict all-cause mortality in patients with CHF.

METHODS

we selected and characterized the subgroup of patients at very high risk with the worst mid-term prognosis belonging to the highest decile of 3C-HF score with the aim to assess predictors of survival in subjects with an expected probability of 1-year mortality near to 45%.

METHODS AND RESULTS

We recruited 1777 consecutive chronic HF patients at 3 Italian Cardiology Units. Median age was 76 ± 10 years, 43% were female, and 32% had preserved ejection fraction. Subjects belonging to the highest decile of 3C-HF score were 246 (13.8% of total population). During a median follow-up of 21 [12-40] months, 110 of these patients (45%) survived and 136 (55%) died. The variables that contributed to survival prediction emerged by Cox regression multivariate analysis were the lower degree of renal dysfunction and higher body mass index.

CONCLUSIONS

The prognostic stratification of chronic HF patients allows in daily practice to select patients at different risk for death and identify prognosticators of survival in outliers at very high risk of death. The reasons why these patients outlive the matching part of subjects who expectedly die are related to the maintenance of a satisfactory renal function and body mass index.

Long-term prognostic impact of therapeutic strategies in patients with idiopathic dilated cardiomyopathy: changing mortality over the last 30 years

AIMS

ACE-inhibitors, β-blockers, implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy (CRT) improved prognosis of heart failure. We sought to analyse the long-term prognostic impact of evidence-based integrated therapeutic strategies in patients with idiopathic dilated cardiomyopathy (IDCM).

METHODS AND RESULTS

From 1978 to 2007, 853 IDCM patients (45 ± 15 years, 72% males) were enrolled and classified as follows: Group 1, 110 patients (12.8%) enrolled during 1978-1987; Group 2, 376 patients (44.1%) enrolled during 1988-1997; Group 3, 367 patients (43.1%) enrolled during 1998-2007. ACE-inhibitors/angiotensin receptor blockers were administered in 34%, 93%, and 93% (P <0.001), and β-blockers in 11%, 82%, and 86% (P <0.001) in Groups 1, 2, and 3, respectively; ICDs were implanted in 2%, 14%, and 13% (P = 0.005); mean time to device implantation was lower in Group 3. At 8 years, heart transplant (HTx)-free survival rates were 55%, 71%, and 87% in Groups 1, 2, and 3, respectively (P <0.001). Similar progressive improvement was found for pump-failure death (DHF)/HTx, while survival free from sudden death (SD) was significantly improved only in Group 3. Multivariable models considering competing risk indicated early diagnosis (i.e. a baseline less advanced disease stage) and tailored medical therapy (HR 0.44, CI 95% 0.19-0.98) as independent protectors against DHF/HTx. Concerning SD, lower left ventricular ejection fraction emerged as a predictor, while ICD was the only therapy with a protective role (HR 0.08, CI 95% 0.01-0.61). Treatment with digitalis emerged as a predictor of both DHF/HTx and SD.

CONCLUSIONS

An effective management and evidence-based integrated therapeutic approach progressively and significantly improved the long-term prognosis of IDCM during the last three decades.

Etiology-dependency of ionic remodeling in cardiomyopathic rabbits

BACKGROUND

Both dilated (DCM) and ischemic cardiomyopathy (ICM) are associated with action potential (AP) prolongation due to ionic remodeling. In humans, AP prolongation is more pronounced in myocytes isolated from explanted DCM than ICM hearts. However, there is a large variability due to confounding factors, including age, sex, concomitant disease, drug treatment, and progression of the disease at the time of heart transplantation. Here, we investigated the etiology-dependency of ionic remodeling in standardized rabbit models of ICM and DCM.

METHODS

ICM and DCM were induced by chronic infarction or combined volume and pressure overload, respectively. APs and membrane currents were measured using patch-clamp methodology.

RESULTS

Both ICM and DCM caused hypertrophy, but this hypertrophy was more prominent in DCM rabbits that also developed heart failure (DCM(F)), as revealed by the presence of ascites. Animals of either model showed AP prolongation. While the AP prolongation was similar by the same degree of hypertrophy, AP prolongation in DCM(F) was more pronounced. In all models, L-type Ca(2+) current, inward rectifier K(+) current, and rapid delayed rectifier K(+) current were unaltered, but the transient outward K(+) current (I(to 1)) density was significantly reduced. The I(to 1) decrease was not associated with differences in voltage-dependency of (in)activation. I(to 1) downregulation was similar in ICM and DCM with the same degree of hypertrophy, but was more pronounced in DCM(F).

CONCLUSIONS

The amount of ionic remodeling and AP prolongation in cardiomyopathic rabbits is due to differences in the amount of hypertrophy rather than differences in the etiology of the cardiomyopathy.

Clinical characteristics and outcome of hospitalized patients with congestive heart failure: results of the HIJC-HF registry

BACKGROUND

Heart failure (HF) represents a major public health issue in an aging population. Although HF is a leading cause of morbidity and mortality in developed countries, the clinical features of HF in Japan remain unclear.

METHODS AND RESULTS

This observational cohort study analyzed data from the Heart Institute of Japan--Department of Cardiology (HIJC)-HF Registry, which is based on a nationwide survey by the HIJC, Tokyo Women's Medical University and its affiliated hospitals. Of 3,578 consecutive patients (average age, 69.8 years; females 40.7%) hospitalized for HF between January 2001 and December 2002, 95.0% were followed up until the end of 2005 (median, 2.8 years). The 1- and 3-year mortality rates were 11.3% and 29.2%, respectively. Multivariate analysis revealed that advanced age (hazard ratio 1.71 [95% confidence interval 1.38-2.12]; p<0.001), symptomatic HF at hospital discharge (3.76 [2.30-6.17]; p<0.001), renal impairment (1.96 [1.50-2.57]; p=0.008), anemia (1.46 [1.18-1.80]; p=0.02) and low pulse pressure (2.88 [1.62-5.13]; p=0.0003) were significantly associated with total death.

CONCLUSION

Although the long-term mortality rate for Japanese patients with HF is lower than in other countries, several markers are modifiable. The data demonstrate that continued improvements in the treatment of Japanese patients with HF are still needed.

Body Mass Index and Prognosis in Patients With Chronic Heart Failure

BACKGROUND

In individuals without known cardiovascular disease, elevated body mass index (BMI) (weight/height2) is associated with an increased risk of death. However, in patients with certain specific chronic diseases, including heart failure, low BMI has been associated with increased mortality.

METHODS AND RESULTS

We examined the influence of BMI on prognosis using Cox proportional hazards models in 7599 patients (mean age, 65 years; 35% women) with symptomatic heart failure (New York Heart Association class II to IV) and a broad spectrum of left ventricular ejection fractions (mean, 39%) in the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) program. During a median follow-up of 37.7 months, 1831 patients died. After adjustment for potential confounders, compared with patients with BMI between 30 and 34.9, patients in lower BMI categories had a graded increase in the risk of death. The hazard ratios (95% confidence intervals) were 1.22 (1.06 to 1.41), 1.46 (1.24 to 1.71), and 1.69 (1.43 to 2.01) among those with BMI of 25 to 29.9, 22.5 to 24.9, and < 22.5, respectively. The increase in risk of death among patients with BMI > or = 35 was not statistically significant (hazard ratio, 1.17; 95% confidence interval, 0.95 to 1.43). The association between BMI and mortality was not altered by age, smoking status, or left ventricular ejection fraction (P for interaction >0.20). However, lower BMI was associated with a greater risk of all-cause death in patients without edema but not in patients with edema (P for interaction <0.0001). Lower BMI was associated with a greater risk of cardiovascular death and noncardiovascular death. Baseline BMI did not influence the risk of hospitalization for worsening heart failure or due to all causes.

CONCLUSIONS

In patients with symptomatic heart failure and either reduced or preserved left ventricular systolic function, underweight or low BMI was associated with increased mortality, primarily in patients without evidence of fluid overload (edema).

Influence of cardiac-resynchronization therapy on heart rate and blood pressure variability: 1-year follow-up

BACKGROUND

Several studies have shown that cardiac-resynchronization therapy (CRT) improves haemodynamic function, cardiac symptoms, and heart rate variability (HRV) and reduces the risk of mortality and sudden death in subjects with chronic heart failure (CHF). In subjects with CHF, power spectral values for the low-frequency (LF) component of RR variability < or =13 ms2, are associated with an increased risk of sudden death.

AIMS AND METHODS

To assess whether spectral indexes obtained by power spectral analysis of HRV and systolic blood pressure (SBP) variability could predict malignant ventricular arrhythmias in patients with severe CHF treated with an implantable cardioverter-defibrillator (ICD) alone or with ICD+CRT. In addition, changes in non-invasive spectral indices using short-term power spectral analysis of HRV and SBP variability during controlled breathing in 15 patients with CHF treated with an ICD alone and 16 patients receiving ICD+CRT, were assessed pre-treatment and at 1 year.

RESULTS

Arrhythmias necessitating an appropriate ICD shock were more frequent in subjects who had low LF power. CRT improved all spectral components, including LF power.

CONCLUSIONS

Low LF power values predict an increased risk of malignant ventricular arrhythmias; after 1 year of CRT most non-spectral and spectral data, including LF power, improved. Whether these improvements lead to better long-term survival in patients with CHF remains unclear.

Validation of prognostic models among patients with advanced heart failure

BACKGROUND

The ability to accurately predict heart failure outcomes is essential to guiding treatment decisions but several competing risk stratification models exist.

METHODS AND RESULTS

We prospectively collected data on 280 patients with advanced heart failure recruited from 16 sites across the United States. Deaths and cardiac transplantations within the following 4 years were identified. Medline was searched to systematically identify widely cited heart failure severity classification models predicting long-term survival among patients with heart failure, and 4 were selected for validation. We used Kaplan-Meier survival curves, receiver-operating characteristic curves, and Cox proportional hazards modeling to identify the prognostic significance of each model's risk score and the individual contribution of the clinical components within each model. Average follow-up was 31.2 months; 148 deaths or transplantations occurred. Each model that we evaluated identified patients with significantly different prognoses. However, each was limited in overall predictive power, and many component patient characteristics did not have independent prognostic significance. Prognostic factors found to be most powerful within their models included: increasing age, ischemic cardiomyopathy, history of cardiomyopathy, ankle edema, decreased peak oxygen consumption, and absence of beta-blocker use.

CONCLUSION

Although each of the models succeeded in risk-stratifying patients to some extent, all 4 models had shortcomings. There is a need for a contemporary model, derived from a patient population managed in accordance with current heart failure guidelines, applicable to all heart failure etiologies, relying on readily available clinical data.

Obesity and Cardiovascular Disease

Obesity is becoming a global epidemic in both children and adults, and it is associated with numerous co-morbidities such as cardiovascular diseases (CVD), type 2 diabetes, hypertension, certain cancers, and sleep apnea/sleep-disordered breathing. In fact, is an independent risk factor for CVD and CVD risks have been also documented in obese children, and is associated with reduced life expectancy. A variety of adaptations/alterations in cardiac structure and function occur in the individual as adipose tissue accumulates in excess amount. As a whole, overweight/obesity predispose or is associated with numerous cardiac complications such as coronary heart disease, heart failure, and sudden death through its impact on the cardiovascular system.

A history of arterial hypertension does not affect mortality in patients hospitalised with congestive heart failure

OBJECTIVES

To evaluate the importance of a history of hypertension on long-term mortality in a large cohort of patients hospitalised with congestive heart failure (CHF).

DESIGN

Retrospective analysis of 5491 consecutive patients, of whom 24% had a history of hypertension. 60% of the patients had non-systolic CHF, and 57% had ischaemic heart disease.

SETTING

38 primary, secondary and tertiary hospitals in Denmark.

MAIN OUTCOME MEASURES

Total mortality 5-8 years after inclusion in the registry.

RESULTS

Female sex and preserved left ventricular systolic function was more common among patients with a history of hypertension. 72% of the patients died during follow up. A hypertension history did not affect mortality risk (hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.92 to 1.07). Correction for differences between the normotensive and hypertensive groups at baseline in a multivariate model did not alter this result (HR 1.08, 95% CI 1.00 to 1.17, p = 0.06). The hazard ratio was similar in patients with and without a history of ischaemic heart disease. Hence, a specific effect of hypertension in the group of patients with CHF with ischaemic heart disease, as suggested in earlier studies, could not be confirmed.

CONCLUSION

A history of arterial hypertension did not affect mortality in patients hospitalised with CHF.

Clinical profile, contemporary management and one-year mortality in patients with severe acute heart failure syndromes: The EFICA study

BACKGROUND

Little is known about the epidemiology of acute decompensated heart failure (ADHF) in patients admitted to intensive and coronary care units (ICU/CCU). Observational data may improve disease management and guide the design of clinical trials.

AIMS

EFICA is an observational study of the clinical profile, management and survival of ADHF patients admitted to ICU/CCU.

METHODS

The study included 599 patients admitted to 60 ICU/CCUs across France. Relevant data was recorded during hospitalisation. Survival was assessed at 4 weeks and 1 year.

RESULTS

The main cause of ADHF was ischaemic heart disease (61%); 29% of patients had cardiogenic shock. Mortality was 27.4% at 4 weeks and 46.5% at 1 year, increasing to 43.2% and 62.5%, respectively, when including pre-admission deaths. Shock patients had the highest [57.8% vs. 15.2% without shock (p < 0.001)] and patients with hypertension and pulmonary oedema had the lowest 4-week mortality: (7%). Pre-admission NYHA class III-IV heart failure, not initial clinical presentation, influenced 1-year mortality.

CONCLUSION

ADHF is a heterogeneous syndrome. Based on initial clinical presentation, three entities with distinct features and outcome may be described: cardiogenic shock, pulmonary oedema with hypertension, and 'decompensated' chronic heart failure. This should be taken into account in future observational studies, guidelines and clinical trials.

The paradox of obesity in patients with heart failure

PURPOSE

Heart failure (HF) patients often have comorbid conditions that confound management and adversely affect prognosis. The purpose of this study was to determine whether the obesity paradox is also present in hospitalized HF patients in an integrated healthcare system.

DATA SOURCES

A cohort of 2707 patients with a primary diagnosis of HF was identified within an integrated, 20-hospital healthcare system. Patients were identified by ICD-9 codes or a left ventricular ejection fraction < or =40% dating back to 1995. Body mass index (BMI) was calculated using the first measured height and weight when hospitalized with HF. Survival rates were calculated using Kaplan Meier estimation. Hazard ratios for 3-year mortality with 95% confidence intervals were assessed using Cox regression, controlling for age, gender, and severity of illness at time of diagnosis.

CONCLUSIONS

Three-year survival rates paradoxically improved for patients with increasing BMI. Survival rates for the larger three BMI quartiles were significantly better than for the lowest quartile after adjusting for severity of illness, age, and gender.

IMPLICATIONS FOR PRACTICE

While obesity increases the risk of developing HF approximately twofold, reports involving stable outpatients suggest that obesity is associated with improved survival after the development of HF. This finding is paradoxical because obesity increases the risk and worsens the prognosis of other cardiovascular diseases.

Neuro-hormonal activation predicts ventilatory response to exercise and functional capacity in patients with heart failure

BACKGROUND

Heart failure (HF) is characterised by reduced tolerance to effort, associated with progressive fatigue and dyspnoea. Neuro-hormonal activation is a hallmark of HF and influences its clinical evolution.

AIM

To evaluate the relationship between neuro-hormonal activation, exercise capacity and ventilatory efficiency.

METHODS AND RESULTS

154 HF patients (127 males, 62 +/- 1 years) underwent cardiopulmonary exercise testing and resting blood sampling for assay of plasma brain natriuretic peptide (BNP), NT-proBNP, norepinephrine, epinephrine, aldosterone and plasma renin activity (PRA). BNP and NT-proBNP levels correlated with peak oxygen consumption (VO2) (both R = -0.53, p < 0.001), VE/VCO2 slope (R = 0.56; p < 0.001 and R = 0.58; p < 0.001, respectively) and maximum workload (R = -0.49; p < 0.001 and R = -0.47; p < 0.001, respectively). Norepinephrine correlated slightly less with peak VO2 (R = -0.38, p < 0.001), VE/VCO2 (R = 0.45; p < 0.001) and maximum workload (R = -0.35; p < 0.001). There was a significant inverse correlation between left ventricular ejection fraction and BNP (R = -0.48, p < 0.001), NT-proBNP (R = -0.42; p < 0.001) and norepinephrine (R = -0.43; p < 0.001). Weaker correlations were found for PRA, exercise parameters and ejection fraction. ROC curves showed that BNP was able to identify patients with peak VO2 < 14 ml/min/kg (cut-off 98 pg/ml, AUC 0.775) and a VE/VCO2 > 35 (cut-off 183 pg/ml, AUC 0.797), as well as NT-proBNP (cut-off 537 pg/ml, AUC 0.799 and cut-off 1010 pg/ml, AUC 0.768, respectively) and norepinephrine (cut-off 454 pg/ml, AUC 0.716 and cut-off 575 pg/ml, AUC 0.783, respectively).

CONCLUSION

Haemodynamic impairment (as indicated by BNP and NT-proBNP plasma values) and sympathetic activation predict exercise capacity and ventilatory efficiency in HF patients.

Obesity and cardiovascular disease: pathophysiology, evaluation, and effect of weight loss: an update of the 1997 American Heart Association Scientific Statement on Obesity and Heart Disease from the Obesity Committee of the Council on Nutrition, Physical Activity, and Metabolism

Obesity is becoming a global epidemic in both children and adults. It is associated with numerous comorbidities such as cardiovascular diseases (CVD), type 2 diabetes, hypertension, certain cancers, and sleep apnea/sleep-disordered breathing. In fact, obesity is an independent risk factor for CVD, and CVD risks have also been documented in obese children. Obesity is associated with an increased risk of morbidity and mortality as well as reduced life expectancy. Health service use and medical costs associated with obesity and related diseases have risen dramatically and are expected to continue to rise. Besides an altered metabolic profile, a variety of adaptations/alterations in cardiac structure and function occur in the individual as adipose tissue accumulates in excess amounts, even in the absence of comorbidities. Hence, obesity may affect the heart through its influence on known risk factors such as dyslipidemia, hypertension, glucose intolerance, inflammatory markers, obstructive sleep apnea/hypoventilation, and the prothrombotic state, in addition to as-yet-unrecognized mechanisms. On the whole, overweight and obesity predispose to or are associated with numerous cardiac complications such as coronary heart disease, heart failure, and sudden death because of their impact on the cardiovascular system. The pathophysiology of these entities that are linked to obesity will be discussed. However, the cardiovascular clinical evaluation of obese patients may be limited because of the morphology of the individual. In this statement, we review the available evidence of the impact of obesity on CVD with emphasis on the evaluation of cardiac structure and function in obese patients and the effect of weight loss on the cardiovascular system.

[Risk stratification in congestive heart failure]

Congestive heart failure remains a severe condition. Risk stratification is necessary to assess the prognosis and discuss the potential timing of heart transplant. Numerous criteria have been used, which may be combined to define prognostic scores which, however, are rarely used in routine. A few items, however, may be used to stratify the risk of mortality and sudden death.

Risk stratification in a Brazilian hospital-based cohort of 1220 outpatients with heart failure: role of Chagas' heart disease

BACKGROUND

Few studies evaluated prognostic factors of outpatients with heart failure of different etiologies including Chagas' heart disease.

METHODS

We studied 1220 outpatients with heart failure in functional classes III and IV (NYHA) to evaluate prognostic factors. Patients aged 13-72 years (mean 45.5, standard deviation 11); 952 men (78%) and 268 women (22%) were followed up for 25.6+/-26 months from 1991 to 2000. Heart failure was attributed to idiopathic dilated cardiomyopathy in 454 (37%) patients. Etiologies were Chagas' heart disease in 242 (20%) patients, ischemic cardiomyopathy in 212 (17%), hypertensive cardiomyopathy in 170 (14%) and others in 142 (12%). Statistical analyses were performed with Kaplan-Meier and Cox proportional hazards methods, following a strategy of noninvasive model as well as in an invasive model to identify the risk of death.

RESULTS

Four hundred fifteen (34%) patients died in the follow-up period, 71 (6%) patients underwent heart transplantation and 28 (2%) underwent other surgical interventions. In the noninvasive model, Chagas' heart disease (relative risk compared with other etiologies 2.26 to 2.97), left ventricular end diastolic diameter on echocardiography (relative risk 1.13) and left ventricular ejection fraction on radionuclide angiography (relative risk 0.96) were associated with higher mortality. In the invasive model, Chagas' heart disease (relative risk compared with other etiologies 2.66 to 9.13) was the most important determinant of mortality in association with the cardiac index (relative risk 0.40).

CONCLUSIONS

In this cohort of patients with heart failure of different etiologies, Chagas' heart disease was the main prognostic factor for mortality.

QT dynamicity: a prognostic factor for sudden cardiac death in chronic heart failure

INTRODUCTION

The aim of this study was to determine whether impaired adaptation of the QT interval to changes in heart rate predicts sudden death in patients with chronic heart failure (CHF).

METHODS

We prospectively included 175 CHF patients in sinus rhythm. QT dynamicity was evaluated by analyzing 24-h Holter recordings. The linear regression slope of QT interval measured to the apex and to the end of T wave plotted against RR intervals was calculated using a dedicated Holter algorithm.

RESULTS

Mean follow-up was 29.9+/-17.9 months. There were 48 deaths, of which 21 were sudden. The actuarial 3-year mortality rates were 38.4% for overall mortality and 14.1% for sudden death. Of all the parameters, an increased QTe/RR slope (>0.28) was the strongest independent predictor of sudden death (relative risk 3.47, 95% confidence interval 1.43-8.40, p=0.006).

CONCLUSION

Increased 24-h QTe dynamicity is independently predictive of sudden death among patients with heart failure. This simple parameter may help to stratify risk and select patients who may benefit from antiarrhythmic prophylaxis.

The risk of cardiovascular death in elderly patients with possible heart failure. Results from a 6-year follow-up of a Swedish primary care population

Little is known about the prognosis and clinical variables influencing the prognosis among elderly patients in primary health care with mild to moderate heart failure.

AIM

To evaluate the risk of cardiovascular mortality in elderly patients with symptoms of heart failure with respect to systolic and diastolic function, and functional impairment. To evaluate prognostic determinants and to risk-stratify the patients.

METHODS

A cardiologist examined 510 patients, out of 548 invited, attending primary care for symptoms of dyspnoea, fatigue and/or peripheral oedema and assessed New York Heart Association (NYHA) functional class. Examination by Doppler echocardiography was done in 454 patients, 56 patients being excluded because of, e.g., atrial fibrillation. Abnormal systolic function was defined as ejection fraction<40%. The diastolic function was evaluated using the mitral inflow and pulmonary venous flow variables. Different clinical and echocardiographic variables were analysed using a Cox regression analysis to identify those most influencing the risk of cardiovascular mortality.

CONCLUSION

Abnormal systolic and/or diastolic function was found in 219 patients (48% of the 454 patients who could be echocardiographically completely investigated). The follow-up period was 6 years. Total mortality was 20%, and cardiovascular mortality was 14% (70% of total mortality). Cardiovascular mortality was high in patients with severely impaired functional capacity and ejection fraction<40% at the start of the study. Risk variables identified were male gender, diabetes mellitus, impaired functional capacity and abnormal cardiac function by echocardiography. A prognostic score model using simple clinical variables (gender, NYHA class, cardiac function) was developed to assess the risk of cardiovascular death in order to identify patients with high, moderate or low risk. In a ROC curve analysis, the AUC for clinical variables was only 0.75, whereas the AUC for clinical variables and echocardiography was 0.78, indicating that the additional prognostic information obtained by Doppler echocardiography was rather small.

Survival advantages of obesity in dialysis patients

In the general population, a high body mass index (BMI; in kg/m(2)) is associated with increased cardiovascular disease and all-cause mortality. However, the effect of overweight (BMI: 25-30) or obesity (BMI: >30) in patients with chronic kidney disease (CKD) undergoing maintenance hemodialysis (MHD) is paradoxically in the opposite direction; ie, a high BMI is associated with improved survival. Although this "reverse epidemiology" of obesity or dialysis-risk-paradox is relatively consistent in MHD patients, studies in CKD patients undergoing peritoneal dialysis have yielded mixed results. Growing confusion has developed among physicians, some of whom are no longer confident about whether to treat obesity in CKD patients. A similar reverse epidemiology of obesity has been described in geriatric populations and in patients with chronic heart failure (CHF). Possible causes of the reverse epidemiology of obesity include a more stable hemodynamic status, alterations in circulating cytokines, unique neurohormonal constellations, endotoxin-lipoprotein interaction, reverse causation, survival bias, time discrepancies among competitive risk factors, and malnutrition-inflammation complex syndrome. Reverse epidemiology may have significant clinical implications in the management of dialysis, CHF, and geriatric patients, ie, populations with extraordinarily high mortality. Exploring the causes and consequences of the reverse epidemiology of obesity in dialysis patients can enhance our insights into similar paradoxes observed for other conventional risk factors, such as blood pressure and serum cholesterol and homocysteine concentrations, and in other populations such as those with CHF, advanced age, cancer, or AIDS. Weight-gaining interventional studies in dialysis patients are urgently needed to ascertain whether they can improve survival and quality of life.

[Mortality prognostic factors of cardiogenic shock complicating an acute myocardial infarction and treated by percutaneous coronary intervention]

OBJECTIVE

To determine the in-hospital prognosis and late outcome of cardiogenic shock complicating acute myocardial infarction treated by early (< 24 hours) percutaneous coronary intervention (PCI).

METHODS

Retrospective monocentric study of a consecutive cohort of patients undergoing early PCI (< 24 heures) for cardiogenic shock complicating acute myocardial infarction from 1994 to 2004.

RESULTS

The cohort included 175 patients (mean age = 65 +/- 14 years, 68% male). A successful PCI was obtained in 69% of patients. The in-hospital mortality was 43%. Independent risk factors associated with an increased mortality were: absence of TIMI three flow (P < 0.0001), absence of smoking (P < 0.009) and the need for mechanical ventilation (P < 0.002). Nor stent use or anti GP IIb/IIa infusions were predictors of a better outcome. At hospital discharge, mean left ventricular ejection fraction (LVEF) was 38 +/- 12%. Kaplan-Meier estimate of survival was 63% for in-hospital survivors (maximum follow-up = 9 years). Independent predictors of an impaired long-term outcome were: a LVEF < 0.3 (P < 0.028) and 3-vessel disease on coronary angiography (P < 0.004).

CONCLUSION

In-hospital mortality of patients suffering cardiogenic shock complicating acute myocardial infarction and treated by PCI remains high despite PCI improvement. The long-term survival appears, however, to be better than that of patients with coronary artery disease and low LVEF.

The long-term outcome of patients with hypertensive cardiomyopathy

The prognosis of dilated cardiomyopathy due to hypertension (HT-DCM) is surprisingly unknown, particularly in the absence of coronary disease and diabetes. We aimed at investigating the long-term outcome and the predictors of mortality in patients with left ventricular systolic dysfunction exclusively due to hypertension. From October 1995 to May 2001, 90 consecutive patients with echocardiographic fractional shortening (FS) < 30% and 29 control patients with FS > or = 30% were included. Obstructive coronary disease was excluded by dipyridamole myocardial perfusion imaging in all patients and coronary angiography in 60. After a mean follow-up of 4.3+/-1.6 years, the total mortality rate of HT-DCM was twice as much higher than that of patients without left ventricular systolic dysfunction (P = 0.01). In HT-DCM, the 5-year mortality rate was 26%. Univariate analyses selected age and creatinine for being positively related to mortality, and body mass index, FS and blood pressure during follow-up for being negatively related to mortality. Neither the improvement of left ventricular FS nor the decrease in left ventricular mass index was related to survival. Multivariate analysis identified (hazard ratio; 95% confidence interval) age (1.08; 1.02-1.13), body mass index (0.86; 0.75-0.98), and baseline FS (0.88; 0.78-0.98) as independent predictors of mortality. In conclusion, poor survival in HT-DCM can be anticipated by the severity of left ventricular systolic dysfunction and advanced age. Instead of ominous signs, high blood pressure and body mass may predict a more favourable prognosis.

Three-dimensional analysis of left ventricle regional wall motion by using gated blood pool tomography

BACKGROUND

We have elaborated a new software called ACS designed for left ventricle 3-dimensional reconstruction and quantitative analysis of regional wall motion using gated blood-pool tomography (GBPS). This paper presents the principle and the validation of this software.

METHODS AND RESULTS

Blood pool tomography was reconstructed by filtered back-projection. Voxels corresponding to ventricular volumes were extracted using 3-D thresholding and 3-D elliptic mask. The auriculoventricular plane was located by phase analysis. Then, the reconstruction of the 3-D volume was initiated. First, a pre-processing based on a bi-dimensional Fourier transform re-sampled the initial points representing the wall of the left ventricle. Left ventricular contraction could be visualized in three dimensions. The points corresponding to the wall of the left ventricle were reorganized in order to obtain a regular sampling that allowed connection to the points during the cardiac cycle. Elementary volumes were defined by three adjacent wall points and the centre of the whole volume. The variation of elementary volumes during the cardiac cycle was related to the wall motion. Elementary volumes were regrouped to create regions of equivalent volume. Finally, regional and global ejection fractions could be calculated in 17 different regions. The method has been validated using a mathematical deformable ellipsoidal model. It had also been tested in vivo on a set of 59 patients in comparison to equilibrium radionuclide angiography for left ventricular ejection fraction and to echocardiography for regional wall motion evaluation.

CONCLUSIONS

ACS is a new software that allows reconstruction and visualization of the left ventricle in three dimensions, and it quantified 3-dimensional regional wall motion analysis.

Effect of obesity and being overweight on long-term mortality in congestive heart failure: influence of left ventricular systolic function

AIMS

Previous studies have suggested that a high body mass index (BMI) is associated with an improved outcome in congestive heart failure (CHF). However, the studies addressing this problem have not included enough patients with non-systolic heart failure to evaluate how left ventricular systolic function interacts with obesity on prognosis in CHF. The aim of this study was to evaluate how BMI influences mortality in patients hospitalized with CHF, and to address in particular whether the effect of BMI is influenced by left ventricular (LV) systolic function.

METHODS AND RESULTS

Retrospective analysis of baseline and survival data for 4700 hospitalized CHF patients for whom BMI was available. LV systolic function, as assessed by wall motion index was available for 95% of the patients. Follow-up time ranged from 5 to 8 years. In the total population, the risk of death decreased steadily with increasing BMI from the underweight to the obese. Compared with normal weight, and adjusted for sex and age, risk ratios (RR) and 95% confidence limits were: underweight 1.56 (1.33-1.84), overweight 0.90 (0.83-0.97), obese 0.77 (0.70-0.86). Being underweight conferred a greater risk in CHF patients with normal systolic function [RR 1.66 (1.29-2.14), compared with normal weight] than in patients with reduced systolic function [RR 1.11 (0.87-1.42), P for interaction 0.03]. In patients with systolic dysfunction, obesity was associated with increased risk compared with normal weight [RR 1.21 (1.01-1.45)].

CONCLUSION

Increasing BMI in CHF is associated with a lower mortality, but the influence is complex and depends on left ventricular systolic function. Hence, in patients with systolic dysfunction obesity may indicate an increased risk.

Impact of obesity on the risk of heart failure and survival after the onset of heart failure

Obesity has reached epidemic proportions in the United States and worldwide. Heart failure (HF) is also a major public health problem, which, despite therapeutic advances, is associated with substantial mortality. The adverse impact of obesity on the cardiovascular system is being increasingly recognized, and includes a hyperdynamic circulation, subclinical cardiac structural and functional changes, and overt HF. At the same time, the possible protective effect of obesity in patients with established HF has been emphasized in recent studies. This article reviews evidence from epidemiologic studies evaluating the impact of overweight and obesity on the risk of HF, appraises published data on the prognostic significance of overweight and obesity after the onset of HF, describes the potential mechanisms underlying these associations,speculates on the clinical implications of current evidence, and suggests directions for future research.

[Prognosis scores to help revascularization for ischemic heart failure]

AIMS

Patients suffering from coronary heart disease with ventricular systolic dysfunction present a bad prognosis and should be potentially revascularized. Up to now, surgery appeared to be the most feasible revascularization technique for such patients. Aims of this study were to assess the influence of different treatments (surgery, angioplasty or exclusively medical treatment) on clinical outcome and to establish a prognostic score practitioners to select the most appropriate therapy adapted to their patient profiles.

METHOD

From 1995 to 2000, 492 patients were included in this cohort: 365 in the angioplasty group, 96 in the surgical group and 31 in the medical group. Kaplan Meier curves were made with a multivariate analysis to determine the significant predictive factors of mortality and major adverse cardiac events.

RESULTS

After a mean follow-up of 32 +/- 19 months, there was no statistical difference in mortality rate between the groups. However, the survival rate without MACE is higher in the surgical group, intermediate in the angioplasty group and lower in the medical group. Using the significant predictive factors of MACE in multivariate analysis, a prognostic score has been established in order to discriminate three categories of severity. For each category, angioplasty was compared with surgery in terms of the event-free-survival rate. For the two extreme categories (severe and non-severe), both treatments were equal. For the intermediate category, surgery obtained greater results.

CONCLUSION

This prognostic score could help physicians in choosing the appropriate revascularization technique to treat patients with severe ischemic heart failure.

Comparative effects of ventricular resynchronization therapy in heart failure patients with or without coronary artery disease

In patients with advanced heart failure, intraventricular conduction delay (IVCD) and left ventricular systolic dysfunction (LVSD), multisite cardiac pacing can be proposed as an additive treatment. The aim of this study was to assess the clinical effectiveness of atrioventricular pacing according to the etiology of LVSD, by comparing the outcome of patients with and without coronary artery disease. Between August 1997 and November 1998, 103 patients were included in the InSync trial and received a biventricular pacemaker and a specifically designed left ventricular pacing lead. Baseline evaluation (12 lead ECG, New York Heart Association Class, quality of life (QOL) and distance walked during the 6 min walk test) was repeated in survival patients at 1, 3, 6 and 12 months after pacemaker implantation. Patients were split in two groups, ischemic (N = 48) and non-ischemic (N = 55), according the result of a recent coronary angiography, the existence of coronary angioplasty or coronary artery bypass or the history of a prior myocardial infarction.

RESULTS

The mortality rate was similar in the two groups with a mean 12 months actuarial survival rate of 78%. Nevertheless, the delay between the death and the pacemaker implantation was significantly higher in the non-ischemic group. A significant reduction in QRS duration and a significant improvement in NYHA class (-1.5). QOL score (-50%) and 6 min walking test (+18%) were observed similarly in the two groups.

CONCLUSION

This study shows that biventricular pacing improves significantly functional status of patients with LVSD, IVCD and advanced heart failure, regardless the etiology of the cardiomyopathy, ischemic or not, without over-mortality in ischemic patients.

Reverse epidemiology of conventional cardiovascular risk factors in patients with chronic heart failure

Traditional risk factors of a poor clinical outcome and mortality in the general population, including body mass index (BMI), serum cholesterol, and blood pressure (BP), are also found to relate to outcome in patients with chronic heart failure (CHF), but in an opposite direction. Obesity, hypercholesterolemia, and high values of BP have been demonstrated to be associated with greater survival among CHF patients. These findings are in contrast to the well-known associations of over-nutrition, hypercholesterolemia, and hypertension with a poor outcome in the general population. The association between traditional cardiovascular risk factors and an adverse clinical outcome in CHF patients is referred to as "reverse epidemiology." The mechanisms for this inverse association in CHF is not clear. There are other populations with a similar risk factor reversal phenomenon, including patients with end-stage renal disease receiving dialysis, those with advanced malignancies, and individuals with advanced age. Several possible causes are hypothesized: the time discrepancy of the competing risk factors may play a role; the presence of the "malnutrition-inflammation complex syndrome" in CHF patients may explain the existence of reverse epidemiology; and a decreased level of lipoprotein molecules may distort their endotoxin-scavenging role, predisposing CHF patients with a low serum cholesterol level to inflammatory consequences of endotoxemia. It is possible that new goals for such traditional risk factors as BMI, serum cholesterol, and BP should be developed for CHF. Reverse epidemiology of conventional cardiovascular risk factors is observed in CHF and may have a bearing on the management of these patients; thus, it deserves further investigation.

Progression of familial and non-familial dilated cardiomyopathy: long term follow up

BACKGROUND

It is unknown whether progression of familial idiopathic dilated cardiomyopathy differs from progression in the non-familial form. It has been suggested that familial disease indicates a worse prognosis, and that this should be considered when planning the timing of heart transplantation.

OBJECTIVE

To compare five year survival or time to heart transplantation in an unselected series of patients with dilated cardiomyopathy who had been evaluated for familial v non-familial disease through the echocardiographic investigation of first degree relatives.

DESIGN

Medical records were reviewed and questionnaires were mailed to all patients who had previously participated in a family based study of dilated cardiomyopathy. Information was gathered about survival, heart transplantation, and left ventricular ejection fraction (LVEF) measurements. Survival data were censored at the time of cardiac transplantation.

RESULTS

Follow up data were obtained for 99 of 101 patients (69 with non-familial and 30 with familial disease). Five year survival was 55% for non-familial and 51% for familial patients (NS). The main predictor of mortality was an LVEF of < 30%. Familial status did not predict mortality. There was no significant difference in follow up LVEF values between the groups.

CONCLUSIONS

Five year survival is not significantly different in the familial and non-familial forms of dilated cardiomyopathy.

Effect of depressive symptoms on survival after heart transplantation

OBJECTIVE

This study explored the value of preoperative self-reported assessment for depression and anxiety in patients who had undergone heart transplantation (HTx). The initial sample was divided into subgroups of patients with ischemic (ICMP) and dilated cardiomyopathy (DCMP). Patient depression and anxiety scores were measured in both subgroups and their impact on pre- and postoperative mortality investigated.

METHOD

An initial sample of 152 patients with either ICMP (N = 57) or DCMP (N = 95) and end-stage heart disease awaiting heart transplantation were assessed in a multidimensional longitudinal study, including psychological and somatic variables. One hundred and three patients received a HTx and were followed up for a mean of 4.4 years. Proportional hazard models were computed to test for the influence of psychosocial and somatic factors on outcome.

RESULTS

Preoperative depression and state anxiety scores were significantly higher in the ICMP group. In addition to donor and recipient age, ICMP patients in the preoperative high depression group also showed a significantly higher mortality after HTx. This result remained significant even after controlling for sociodemographic and somatic variables.

CONCLUSIONS

Patient self-reported depression, but not anxiety, can contribute to the identification of subgroups of patients with an unfavorable outcome after HTx. It therefore may be helpful to screen for depression, particularly in patients with an ischemic cause of their end-stage heart disease. Specific intervention programs should be further developed and evaluated.

The prognostic value of body mass index and standard exercise testing in male veterans with congestive heart failure

OBJECTIVE

To evaluate the prognostic characteristics of body mass index (BMI) and standard exercise test variables in a consecutive series of patients with mild to moderate congestive heart failure (CHF) referred for standard exercise tests.

BACKGROUND

Controversy exists regarding the prognostic importance of BMI, etiology, and exercise test variables in patients with CHF.

METHODS

All patients referred for evaluation at two university-affiliated Veterans Affairs Medical Centers who underwent treadmill tests for clinical indications between 1987 and 2000 were determined to be dead or alive using the Social Security Death Index after a mean 6 years follow-up. Clinical and exercise test variables were collected prospectively according to standard definitions; testing and data management were performed in a standardized fashion using a computer-assisted protocol. Survival analysis was performed using all-cause mortality as the endpoint for follow-up.

RESULTS

A total of 522 patients with a history and clinical findings of CHF underwent exercise testing. Forty-two percent died during the follow-up period, for an average annual mortality of 6.7%. Cox proportional hazards model chose peak metabolic equivalents (METs), BMI, age, and ischemic etiology in rank order as independently and significantly associated with time to death. A score based on these variables classified patients into low (2% annual mortality), medium (5.2%), and high-risk groups (7% annual mortality).

CONCLUSION

Standard exercise testing and BMI can be used to estimate prognosis in outpatients with heart failure. A score incorporating METs, BMI, age, and etiology efficiently stratified these patients. BMI was chosen by the survival analysis, confirming its surprising inverse relationship to prognosis in CHF patients (i.e., heavier patients do better).

Self-rating of quality of life provides additional prognostic information in heart failure. Insights into the EPICAL study

BACKGROUND

The relationship between quality of life (QoL) and survival have been poorly investigated. The aim of this study was to determine the value of QoL score as a prognostic factor in a prospective cohort of patients with advanced chronic heart failure (CHF).

METHODS

QoL assessment was performed with a generic questionnaire: the Duke Health Profile (DHP) and a disease-specific instrument: the Minnesota Living With Heart Failure Questionnaire (LIhFE), in a sample of 108 patients registered in the EPICAL program (hospitalised patients with severe CHF defined by a NYHA grade III/IV, oedema or hypotension, and LVEF < 30%). Prognostic value of general, physical, mental and social dimensions on survival and hospital-free survival were tested in a Cox model.

RESULTS

One-year survival rate was 76%, 1-year hospital-free survival 38%. QoL was significantly associated with outcomes: for both questionnaires, a 10-point decrement in baseline score was associated with a 23-36% increase in the risk of death or hospitalisation for heart failure. For hospital-free survival, this relationship remained significant after adjustment for others prognostic factors.

CONCLUSION

QoL score is a predictive factor of survival and an independent predictive factor of hospital-free survival in patients with advanced CHF. This assessment may provide additional information for clinical management and therapeutic decisions.

Risk stratification in middle-aged patients with congestive heart failure: prospective comparison of the Heart Failure Survival Score (HFSS) and a simplified two-variable model

AIMS

The performance of a US-American scoring system (Heart Failure Survival Score, HFSS) was prospectively evaluated in a sample of ambulatory patients with congestive heart failure (CHF). Additionally, it was investigated whether the HFSS might be simplified by assessment of the distance ambulated during a 6-min walk test (6'WT) instead of determination of peak oxygen uptake (peak VO(2)).

METHODS AND RESULTS

In 208 middle-aged CHF patients (age 54+/-10 years, 82% male, NYHA class 2.3+/-0.7; follow-up 28+/-14 months) the seven variables of the HFSS: CHF aetiology; heart rate; mean arterial pressure; serum sodium concentration; intraventricular conduction time; left ventricular ejection fraction (LVEF); and peak VO(2), were determined. Additionally, a 6'WT was performed. The HFSS allowed discrimination between patients at low, medium and high risk, with mortality rates of 16, 39 and 50%, respectively. However, the prognostic power of the HFSS was not superior to a two-variable model consisting only of LVEF and peak VO(2). The areas under the receiver operating curves (AUC) for prediction of 1-year survival were even higher for the two-variable model (0.84 vs. 0.74, P<0.05). Replacing peak VO(2) with 6'WT resulted in a similar AUC (0.83).

CONCLUSION

The HFSS continued to predict survival when applied to this patient sample. However, the HFSS was inferior to a two-variable model containing only LVEF and either peak VO(2) or 6'WT. As the 6'WT requires no sophisticated equipment, a simplified two-variable model containing only LVEF and 6'WT may be more widely applicable, and is therefore recommended.