Differential Associations of A-/B-Type Natriuretic Peptides With Cardiac Structure, Function, and Prognosis in Heart Failure

BACKGROUND

Natriuretic peptide (NP) elevations are prognostic in heart failure (HF), but relative atrial NP deficiency in acute HF has been suggested.

OBJECTIVES

The authors compared plasma concentrations and relative strength of associations of A- and B-type NPs with cardiac structure/function and clinical outcomes in HF.

METHODS

Midregional pro-atrial natriuretic peptide (MR-proANP), B-type natriuretic peptide (BNP), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were measured in patients with compensated HF in a prospective, multicenter study. The primary outcome was a composite of HF-hospitalization or all-cause mortality. Secondary outcomes included individual primary outcome components and cardiovascular admission.

RESULTS

Among 1,278 patients (age 60.1 ± 12.1 years, 82% men, left ventricular ejection fraction [LVEF] 34% ± 14%), median concentrations of MR-proANP were 990 pg/mL (Q1-Q3: 557-1,563 pg/mL), NT-proBNP 1,648 pg/mL (Q1-Q3: 652-3,960 pg/mL), and BNP 291 pg/mL (Q1-Q3: 103-777 pg/mL). No subpopulation with inappropriately low MR-proANP (relative to BNP/NT-proBNP) was observed. Clinical event rates were similar for biomarker tertiles. Increments in MR-proANP exhibited steeper associations with concurrent shifts in left ventricular size, diastolic indexes and LVEF than BNP/NT-proBNP at baseline and serially (P < 0.05), and lower odds of beneficial left ventricular reverse remodeling: OR: 0.35 (95% CI: 0.18-0.70). In single-biomarker models, MR-proANP(log10) was associated with the highest hazard (4 to 6 times) for each outcome. In multimarker models, independent associations were observed for the primary outcome (MR-proANP and NT-proBNP), HF-hospitalization and cardiovascular admission (MR-proANP only), and all-cause mortality (NT-proBNP only) (P < 0.05). The discriminative value of MR-proANP was superior to BNP/NT-proBNP (HF-hospitalization) and BNP (primary outcome) (P < 0.05).

CONCLUSIONS

MR-proANP was not inappropriately low relative to concurrent BNP/NT-proBNP values. Proportional increments in MR-proANP were more pronounced than for B-peptides for given decrements in cardiac structure/function. MR-proANP offered greater independent predictive power overall.

Circulating levels and prognostic cut-offs of sST2, hs-cTnT, and NT-proBNP in women vs. men with chronic heart failure

Aims

To define plasma concentrations, determinants, and optimal prognostic cut‐offs of soluble suppression of tumorigenesis‐2 (sST2), high‐sensitivity cardiac troponin T (hs‐cTnT), and N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) in women and men with chronic heart failure (HF).

Methods and results

Individual data of patients from the Biomarkers In Heart Failure Outpatient Study (BIOS) Consortium with sST2, hs‐cTnT, and NT‐proBNP measured were analysed. The primary endpoint was a composite of 1 year cardiovascular death and HF hospitalization. The secondary endpoints were 5 year cardiovascular and all‐cause death. The cohort included 4540 patients (age 67 ± 12 years, left ventricular ejection fraction 33 ± 13%, 1111 women, 25%). Women showed lower sST2 (24 vs. 27 ng/mL, P < 0.001) and hs‐cTnT level (15 vs. 20 ng/L, P < 0.001), and similar concentrations of NT‐proBNP (1540 vs. 1505 ng/L, P = 0.408). Although the three biomarkers were confirmed as independent predictors of outcome in both sexes, the optimal prognostic cut‐off was lower in women for sST2 (28 vs. 31 ng/mL) and hs‐cTnT (22 vs. 25 ng/L), while NT‐proBNP cut‐off was higher in women (2339 ng/L vs. 2145 ng/L). The use of sex‐specific cut‐offs improved risk prediction compared with the use of previously standardized prognostic cut‐offs and allowed to reclassify the risk of many patients, to a greater extent in women than men, and for hs‐cTnT than sST2 or NT‐proBNP. Specifically, up to 18% men and up to 57% women were reclassified, by using the sex‐specific cut‐off of hs‐cTnT for the endpoint of 5 year cardiovascular death.

Conclusions

In patients with chronic HF, concentrations of sST2 and hs‐cTnT, but not of NT‐proBNP, are lower in women. Lower sST2 and hs‐cTnT and higher NT‐proBNP cut‐offs for risk stratification could be used in women.

Cardiac biomarkers retain prognostic significance in patients with heart failure and chronic obstructive pulmonary disease

AIMS

Chronic obstructive pulmonary disease (COPD) is a frequent comorbidity in patients with heart failure (HF). We assessed the influence of COPD on circulating levels and prognostic value of three HF biomarkers: N-terminal pro-B-type natriuretic peptide (NT-proBNP), high-sensitivity troponin T (hs-TnT), and soluble suppression of tumorigenesis-2 (sST2).

METHODS

Individual data from patients with chronic HF, known COPD status, NT-proBNP and hs-TnT values (n = 8088) were analysed. A subgroup (n = 3414) had also sST2 values.

RESULTS

Patients had a median age of 66 years (interquartile interval 57-74), 77% were men and 82% had HF with reduced ejection fraction. NT-proBNP, hs-TnT and sST2 were 1207 ng/l (487-2725), 17 ng/l (9-31) and 30 ng/ml (22-44), respectively. Patients with COPD (n = 1249, 15%) had higher NT-proBNP (P = 0.042) and hs-TnT (P < 0.001), but not sST2 (P = 0.165). Over a median 2.0-year follow-up (1.5-2.5), 1717 patients (21%) died, and 1298 (16%) died from cardiovascular causes; 2255 patients (28%) were hospitalized for HF over 1.8 years (0.9-2.1). NT-proBNP, hs-TnT and sST2 predicted the three end points regardless of COPD status. The best cut-offs from receiver-operating characteristics analysis were higher in patients with COPD than in those without. Patients with all three biomarkers higher than or equal to end-point- and COPD-status-specific cut-offs were also those with the worst prognosis.

CONCLUSIONS

Among patients with HF, those with COPD have higher NT-proBNP and hs-TnT, but not sST2. All these biomarkers yield prognostic significance regardless of the COPD status.

41 Circulating levels and prognostic cut-offs of sST2, high-sensitivity troponin T, and NT-proBNP in women vs. men with chronic heart failure

Aims

Limited evidence exists on sex-related differences in clinical value of biomarkers in chronic heart failure (HF). We aimed to define plasma levels, determinants, and optimal prognostic cut-offs of soluble suppression of tumourigenesis-2 (sST2), high-sensitivity troponin T (hs-TnT), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in female and male chronic HF patients.

Methods and results

Individual data of patients from the BIOS (Biomarkers In Heart Failure Outpatient Study) Consortium with sST2, hs-TnT, and NT-proBNP measured were analysed. The primary endpoint was a composite of 1-year cardiovascular death and HF hospitalization. The secondary endpoints were 5-year cardiovascular and all-cause death. The cohort included 4540 patients (age: 67 ± 12 years, LVEF 33 ± 13%, 1111 women, 25%). Women showed lower sST2 (24 vs. 27 ng/ml, P &lt; 0.001) and hs-TnT level (15 vs. 20 ng/l, P &lt; 0.001), and similar concentrations of NT-proBNP (1540 vs. 1505 ng/l, P = 0.408). Although the three biomarkers were confirmed as independent predictors of outcome in both sexes, the optimal prognostic cut-off was lower in women for sST2 (28 vs. 31 ng/ml) and hs-TnT (22 vs. 25 ng/l), while NT-proBNP cut-off was higher in women (2339 ng/l vs. 2145 ng/l). The use of sex-specific cut-offs improved risk prediction compared to the use of previously standardized prognostic cut-offs (Figure).

Conclusions

In patients with chronic HF, levels of sST2 and hs-TnT, but not of NT-proBNP are lower in women. Lower sST2 and hs-TnT and higher NT-proBNP cut-offs for risk stratification could be used in women.

Impact of change in iron status over time on clinical outcomes in heart failure according to ejection fraction phenotype

Aims

The importance of iron deficiency (ID) in heart failure with preserved ejection fraction (HFpEF) is unknown. In HF with reduced ejection fraction (HFrEF), ID is reported as an independent predictor of mortality in HF although not all published studies agree. Different definitions of ID have been assessed, and the natural history of untreated ID not established, which may explain the conflicting results. This study aimed to assess the relationship between ID and mortality in HFpEF, clarify which definition of ID correlates best with outcomes in HFrEF, and determine the prognostic importance of change in ID status over time.

Methods and results

Analyses were conducted on data from 1563 patients participating in a prospective international cohort study comparing HFpEF with HFrEF. Plasma samples from baseline and 6 month visits were analysed for the presence of ID. Two ID definitions were evaluated: ID_Ferritin = ‘ferritin < 100 mcg/L or ferritin 100–300 mcg/L + transferrin saturation < 20%’ and ID_Tsat = ‘transferrin saturation < 20%’. The risk of all‐cause mortality and death/HF hospitalization associated with baseline ID (ID_Ferritin or ID_Tsat) and change in ID status at 6 months (persistent, resolving, developing, or never present) was estimated in multivariable Cox proportional hazards models. Of 1563 patients, 1115 (71%) had HFrEF and 448 (29%) HFpEF. Prevalence of ID was similar in HFpEF and HFrEF (58%). Patients with ID were more likely to be female, diabetic, and have a higher co‐morbid burden than patients without ID. ID by either definition did not confer independent risk for either all‐cause mortality or death/HF hospitalization for patients with HFpEF [ID_Ferritin hazard ratio (HR) 0.65 (95% confidence interval 0.40–1.05), P = 0.08; ID_Tsat HR 1.16 (0.72–1.87), P = 0.55]. In the overall study cohort (HFrEF + HFpEF) and HFrEF subgroup, ID_Ferritin was inferior to ID_Tsat in prediction of all‐cause mortality [overall cohort: HR 1.21 (0.95–1.53), P = 0.12 vs. HR 1.95 (1.52–2.51), P < 0.01; HFrEF: HR 1.12 (0.85–1.48), P = 0.43 vs. HR 1.57 (1.15–2.14), P < 0.01]. Persistence of ID_Tsat at 6 months was strongly associated with poor outcomes compared with never having ID_Tsat [HR 2.22 (1.42–3.46), P < 0.01] or having ID_Tsat at baseline self‐resolve by 6 months [HR 1.40 (1.06–1.86), P = 0.02].

Conclusions

Iron deficiency is equally prevalent in HFpEF and HFrEF but is negatively prognostic only in HFrEF. The natural history of ID is important; persistent ID is strongly associated with mortality whereas resolution is not. ID_Tsat is the superior definition of ID and should inform future trials investigating the efficacy of intravenous iron replacement in patients with HFrEF.

Mortality associated with heart failure with preserved vs. reduced ejection fraction in a prospective international multi-ethnic cohort study

Aims

Whether prevalence and mortality of patients with heart failure with preserved or mid-range (40-49%) ejection fraction (HFpEF and HFmREF) are similar to those of heart failure with reduced ejection fraction (HFrEF), as reported in some epidemiologic studies, remains highly controversial. We determined and compared characteristics and outcomes for patients with HFpEF, HFmREF, and HFrEF in a prospective, international, multi-ethnic population.

Methods and results

Prospective multi-centre longitudinal study in New Zealand (NZ) and Singapore. Patients with HF were assessed at baseline and followed over 2 years. The primary outcome was death from any cause. Secondary outcome was death and HF hospitalization. Cox proportional hazards models were used to compare outcomes for patients with HFpEF, HFmrEF, and HFrEF. Of 2039 patients enrolled, 28% had HFpEF, 13% HFmrEF, and 59% HFrEF. Compared with HFrEF, patients with HFpEF were older (62 vs. 72 years), more commonly female (17% vs. 48%), and more likely to have a history of hypertension (61% vs. 78%) but less likely to have coronary artery disease (55% vs. 41%). During 2 years of follow-up, 343 (17%) patients died. Adjusting for age, sex, and clinical risk factors, patients with HFpEF had a lower risk of death compared with those with HFrEF (hazard ratio 0.62, 95% confidence interval 0.46-0.85). Plasma (NT-proBNP) was similarly related to mortality in both HFpEF, HFmrEF, and HFrEF independent of the co-variates listed and of ejection fraction. Results were similar for the composite endpoint of death or HF and were consistent between Singapore and NZ.

Conclusion

These prospective multinational data showed that the prevalence of HFpEF within the HF population was lower than HFrEF. Death rate was comparable in HFpEF and HFmrEF and lower than in HFrEF. Plasma levels of NT-proBNP were independently and similarly predictive of death in the three HF phenotypes.

Trial Registration

Australian New Zealand Clinical Trial Registry (ACTRN12610000374066).

Cornell product is an ECG marker of heart failure with preserved ejection fraction

Objective

ECG markers of heart failure (HF) with preserved ejection fraction (HFpEF) are lacking. We hypothesised that the Cornell product (CP) is a risk marker of HFpEF and has prognostic utility in HFpEF.

Methods

CP =[(amplitude of R wave in aVL+depth of S wave in V3)×QRS] was measured on baseline 12-lead ECG in a prospective Asian population-based study of 606 healthy controls (aged 55±10 years, 45% men), 221 hypertensive controls (62±9 years, 58% men) and 242 HFpEF (68±12 years, 49% men); all with EF ≥50% and followed for 2 years for all-cause mortality and HF hospitalisations.

Results

CP increased across groups from healthy controls to hypertensive controls to HFpEF, and distinguished between HFpEF and hypertension with an optimal cut-off of ≥1800 mm*ms (sensitivity 40%, specificity 85%). Age, male sex, systolic blood pressure (SBP) and heart rate were independent predictors of CP ≥1800 mm*ms, and CP was associated with echocardiographic E/e' (r=0.27, p<0.01) and left ventricular mass index (r=0.46, p<0.01). Adjusting for clinical and echocardiographic variables and log N-terminal pro B-type natriuretic peptide (NT-proBNP), CP ≥1800 mm*ms was significantly associated with HFpEF (adjusted OR 2.7, 95% CI 1.0 to 7.0). At 2-year follow-up, there were 29 deaths and 61 HF hospitalisations, all within the HFpEF group. Even after adjusting for log NT-proBNP, clinical and echocardiographic variables, CP ≥1800 mm*ms remained strongly associated with a higher composite endpoint of all-cause mortality and HF hospitalisations (adjusted HR 2.1, 95% CI 1.2 to 3.5).

Conclusion

The Cornell product is an easily applicable ECG marker of HFpEF and predicts poor prognosis by reflecting the severity of diastolic dysfunction and LV hypertrophy.

Ethnic differences in atrial fibrillation in patients with heart failure from Asia-Pacific

OBJECTIVE

Ethnic differences in the prevalence of atrial fibrillation (AF) in heart failure (HF) remain unclear. We compared the prevalence and clinical correlates of AF among different ethnicities in an Asian-Pacific population with HF.

METHODS

Patients with validated HF were prospectively studied across Singapore and New Zealand (NZ).

RESULTS

Among 1746 patients with HF (62% Asian, 26% women, mean age 66 (SD 13) years, mean ejection fraction (EF) 37 (SD 16%), 39% had AF. The prevalence of AF was markedly lower in Singapore-Asians than NZ-Europeans (24% vs 63%; p<0.001), even after adjusting for age, clinical and echocardiographic covariates, regardless of EF group (p_interaction for EF=0.39). Patients with AF were older, had higher body mass index and were more likely to have a history of hypertension, stroke, peripheral vascular disease, renal disease, chronic respiratory disease and increased alcohol intake, but less likely to have diabetes. Clinical correlates were similar for Asians and NZ-Europeans, except diabetes: Asian diabetic patients with HF had less AF compared with Asian patients without diabetes (OR 0.66, 95% CI 0.50 to 0.88), whereas among NZ-Europeans there was no significant association between diabetes and AF (OR 1.22, 95% CI 0.85 to 1.75) (p_interaction for ethnicity=0.01). AF was associated with a higher crude composite outcome of mortality and HF hospitalisations at 2 years (HR 1.19, 95% CI 1.02 to 1.38).

CONCLUSION

There is a strikingly lower prevalence of AF among Asian compared with NZ-European patients with HF. The underlying mechanisms for the lower prevalence of AF among Asians, particularly in the presence of diabetes, deserve further study.

TRIAL REGISTRATION NUMBER

ACTRN12610000374066.

Cost-effectiveness of sacubitril/valsartan versus enalapril in patients with heart failure and reduced ejection fraction

BACKGROUND

Sacubitril/valsartan reduces cardiovascular death and hospitalizations for heart failure (HF). However, decision-makers need to determine whether its benefits are worth the additional costs, given the low-cost generic status of traditional standard of care.

AIMS

To evaluate the cost-effectiveness of sacubitril/valsartan compared to enalapril in patients with HF and reduced ejection fraction, from the Singapore healthcare payer perspective.

METHODS

A Markov model was developed to project clinical and economic outcomes of sacubitril/valsartan vs enalapril for 66-year-old patients with HF over 10 years. Key health states included New York Heart Association classes I-IV and deaths; patients in each state incurred a monthly risk of hospitalization for HF and cardiovascular death. Sacubitril/valsartan benefits were modeled by applying the hazard ratios (HRs) in PARADIGM-HF trial to baseline probabilities. Primary model outcomes were total and incremental costs and quality-adjusted life years (QALYs) and the incremental cost-effectiveness ratio (ICER) for sacubitril/valsartan relative to enalapril Results: Compared to enalapril, sacubitril/valsartan was associated with an ICER of SGD 74,592 (USD 55,198) per QALY gained. A major driver of cost-effectiveness was the cardiovascular mortality benefit of sacubitril/valsartan. The uncertainty of this treatment benefit in the Asian sub-group was tested in sensitivity analyses using a HR of 1 as an upper limit, where the ICERs ranged from SGD 41,019 (USD 30,354) to SGD 1,447,103 (USD 1,070,856) per QALY gained. Probabilistic sensitivity analyses showed the probability of sacubitril/valsartan being cost-effective was below 1%, 12%, and 71% at SGD 20,000, SGD 50,000, and SGD 100,000 per QALY gained, respectively.

CONCLUSIONS

At the current daily price sacubitril/valsartan may not represent good value for limited healthcare dollars compared to enalapril in reducing cardiovascular morbidity and mortality in HF in the Singapore healthcare setting. This study highlights the cost-benefit trade-off that healthcare professionals and patients face when considering therapy.

Prognostic Factors After Index Hospitalization for Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) has a high clinical burden and constitutes approximately 20% to 30% of patients with heart failure in Asia. Impaired global longitudinal strain (GLS), defined as an absolute value of <15.8%, has been shown to be a predictor of heart failure hospitalization, cardiovascular death, and aborted cardiac arrest in HFpEF. We sought to validate this finding in our Asian cohort and identify other prognostic factors in HFpEF. In this cohort study, we included all patients with an index hospitalization for heart failure and left ventricular ejection fraction of >45%, from January 1, 2012, to December 31, 2012. All patients had follow-up for at least 3 years. In our study, the absolute value of mean GLS was impaired at 13.50 ± 4.00%, whereas mean left ventricular ejection fraction was 52.00 ± 7.67%. In multivariate Cox regression, impaired GLS of absolute value <15.8% (hazard ratio 4.72, 95% CI 1.25 to 17.81, p = 0.022), every unit increase in age-adjusted Charlson Comorbidity Index (hazard ratio 1.46, 95% CI 1.03 to 2.05, p = 0.031) and low body mass index <18.5 kg/m² (hazard ratio 4.30, 95% CI 1.25 to 14.78, p = 0.020) were associated with a shorter time to mortality over the 3-year period. Our study validates absolute GLS value of <15.8% to be a prognostic marker for patients with HFpEF.

Risk Stratification Model for 30-Day Heart Failure Readmission in a Multiethnic South East Asian Community

There are limited accurate 30-day heart failure (HF) readmission risk scores using readily available clinical patient information on a well-defined HF cohort. We analyzed 1,475 admissions discharged from our hospital with a primary diagnosis of HF between 2010 and 2012. HF diagnostic criteria included satisfying clinical Framingham criteria, elevated serum N-terminal pro-natriuretic peptide, and evidence of cardiac dysfunction on transthoracic echocardiography. The patients were randomly divided into 2 groups; 60% were used as the derivation cohort and 40% as the validation cohort. Bivariate analysis and logistic regression were used to develop the model. Weighted risk scores were derived from the odds ratio of the logistic regression model. Total risk scores were computed by simple summation for each patient. The 7 significant independent predictors of 30-day HF readmission used to derive the risk scoring tool were the number of previous HF-related admission in the preceding 1 year, index admission length of stay, serum creatinine level, electrocardiograph QRS duration, serum N-terminal pro-natriuretic peptide level, number of Medical Social Service needs, and β blocker prescription on discharge. The area under the curve was 0.76. Sensitivity and specificity were 78.3% and 60.7%, respectively. The positive predictive value and negative predictive value were 18.9% and 96%, respectively. The actual observed and predicted 30-day heart failure readmission rates matched. In conclusion, we have developed the first 30-day HF readmission risk score, with good discriminatory ability, for an urban multiethnic Asian heart failure cohort with stringent diagnostic criteria. It consists of 7 easily obtained variables.

Comparison of Characteristics and Outcomes of Heart Failure Patients With Preserved Versus Reduced Ejection Fraction in a Multiethnic Southeast Asian Cohort

There are few data comparing the patient characteristics and outcomes of heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced EF (HFrEF) in Asian cohorts. We aimed to evaluate the prevalence, clinical characteristics, and 1-year outcomes of a well-defined Southeast Asian HFpEF cohort in comparison to an HFrEF cohort. We conducted a retrospective observational study of 1,978 patients discharged from Changi General Hospital, Singapore with a primary diagnosis of HF from 2009 to 2013. About 29% of discharges had HFpEF. Patients with HFpEF were more likely to be women, older age, and have a higher prevalence of hypertension. There were no significant differences in the absolute rates of 30-day outcomes between the 2 groups. The absolute rate of death at 1 year was similar in HFrEF and HFpEF at 17% and 15%, respectively (p = 0.3). After multivariate adjustment, there was no difference in the outcomes of the 2 groups. Atrial fibrillation at baseline was a predictor of death or HF hospitalization in HFpEF but not HFrEF (interaction p = 0.003). In conclusion, in this study of a Southeast Asian population with well-defined HF, we found that the clinical profile of patients with HF was similar to that in the West and 30-day and 1-year mortality and morbidity were not significantly different between cohorts.

Renal sympathetic denervation for the treatment of refractory hypertension

Resistant hypertension poses significant health concerns. There are strong demands for new and safe therapies to control resistant hypertension while addressing its common causes, specifically poor compliance to lifelong polypharmacy, lifestyle modifications, and physician inertia. The sympathetic nervous system plays a significant pathophysiological role in hypertension. Surgical sympathectomy for blood pressure reduction is an old but extremely efficacious therapeutic concept, now abandoned with the dawn of a safer contemporary pharmacology era. Recently, clinical studies have revealed promising results for safe and sustained blood pressure reduction with percutaneous renal sympathetic denervation. This is a novel, minimally invasive, device-based therapy, specifically targeting and ablating the renal artery nerves with radiofrequency waves without permanent implantation. There are also reported additional benefits in related comorbidities, such as impaired glucose metabolism, renal impairment, left ventricular hypertrophy, heart failure, and others. This review focuses on how selective renal sympathetic denervation works, its present and potential therapeutic indications, and its future directions.

Iron deficiency in a multi-ethnic Asian population with and without heart failure: prevalence, clinical correlates, functional significance and prognosis

AIMS

Current heart failure (HF) guidelines highlight the importance of iron deficiency (ID) in HF. Whether HF itself or age-related comorbidities contribute to ID is uncertain, and previous data were limited to Western populations. We aimed to study the prevalence, clinical correlates, functional significance and prognosis of ID in HF patients, compared with community-based controls in a multi-ethnic Southeast Asian population.

METHODS AND RESULTS

Iron status was assessed in 751 HF patients (age 62.0 ± 12.2 years, 75.5% men, 64.7% Chinese, 23.9% Malay, 10.2% Indian) and 601 controls (age 56.9 ± 10.4 years, 49.8% men, 70.9% Chinese, 21.5% Malay, 7.2% Indian). ID, defined as ferritin <100 µg/L or ferritin 100-300 µg/L and transferrin saturation (Tsat) <20%, was present in 39.3% of controls and 61.4% of HF [odds ratio (OR) 3.5, 95% confidence interval (CI) 2.5-4.9, adjusting for clinical covariates]. Independent correlates of ID in HF were Indian ethnicity (OR 2.4 vs. Chinese, 95% CI 1.2-5.0), female gender (OR 2.8, 95% CI 1.7-4.8), larger body mass index (OR 1.05/unit increase, 95% CI 1.01-1.1) and decreased left ventricular ejection fraction (OR 1.03/unit decrease, 95% CI 1.01-1.04). In a subset of 48 HF patients undergoing cardiopulmonary exercise testing, Tsat correlated with peak oxygen consumption (ρ = 0.53, P < 0.01), independent of baseline characteristics. The HF patients with Tsat <20% as well as anaemia showed the poorest event-free survival after adjusting for clinical covariates.

CONCLUSIONS

ID was highly prevalent and independently related to functional capacity and outcomes in our cohort. These findings suggest a pathophysiological role of ID in HF and support its importance as a therapeutic target in Southeast Asian patients with HF.

Precipitant in acute heart failure in a multiethnic Asian urban cohort study

OBJECTIVES

To identify acute heart failure (HF) precipitants in patients with a history of chronic HF, and to analyse any relationship with early outcomes.

BACKGROUND

There are limited studies on acute HF precipitants and the relationship with outcomes, and determining this will help to identify the avoidable precipitants and may lead to better outcomes.

METHODS

Patients with a history of HF and admission to the authors' hospital in 2008, with a discharge primary diagnosis of HF, were enrolled. Diagnosis of HF was prospectively defined and reviewed by two cardiology teams. Patients' case records were reviewed, or families were interviewed for 1-month follow-up outcome information.

RESULTS

242 admissions by 185 patients constituted our study cohort. Patients were older, and 36.8% were females. The ethnic Chinese, Malay and Indian composition of the cohort were 41.3%, 35.1% and 16.1% respectively. The mean left-ventricular ejection fraction was 34.0±17.5%. Preserved left ventricular ejection fraction (≥45%) constituted 35.1% of the cohort. Acute HF precipitants were identified in 62.8% of admissions and unidentified in 37.2% admissions. Non-compliance issues and infections constituted 27.2% and 13.6% of precipitants respectively. Cardiac precipitants accounted for 10.0% admissions. Multiple precipitants accounted for 8.3% admissions. There were no significant differences in patient profile, including ethnicity and gender, and outcomes between patients with identified precipitants and patients with unidentified precipitants.

CONCLUSION

Non-compliance issues were a major precipitant of acute HF in patients with chronic HF. Precipitants were not determined in 37.2% of admissions. There were no significant associations between the different types of precipitants and early 30-day outcomes.

Heart failure cohort in Singapore with defined criteria: clinical characteristics and prognosis in a multi-ethnic hospital-based cohort in Singapore

INTRODUCTION

There are limited data on heart failure (HF) cohorts with objective clinical definition of HF. Many observational HF studies were based on discharge diagnosis codes, making them subjective. Many did not have contemporaneous left ventricular function assessment. This study was done to evaluate the characteristics and one-year prognosis of a single centre multi-ethnic Asian inpatient HF cohort, with these limitations addressed, with the aim of yielding a more accurate picture of true HF.

METHODS

This was an observational prospective study. Patients who fulfilled the modified Framingham criteria for clinical HF and study inclusion criteria of serum creatinine level less than 267 micromol/L, serum albumin level greater than 28 g/L, and a contemporaneous trans-thoracic echocardiography (TTE) study were enrolled. TTE studies ordered were attempted within 72 hours.

RESULTS

173 patients were enrolled into the study. TTE was done within 72 hours of admission for 86.1 percent (n = 149) of the participants. Diastolic HF constituted 22.0 percent of the cohort. The mean age of the participants was 68.7 (standard deviation, 12.0) years. The prevalence of elderly patients, diabetes mellitus, hypertension and ischaemic cardiomyopathy were high. The one-year mortality rate was 20.8 percent (n = 36). The one-year death or readmission for any cause rate was 69.4 percent (n = 120). The mean time in hospital for any cause within the one year was 11.8 +/- 17.9 days. Ethnicity had prognostic implications. Being elderly, having elevated random blood glucose or serum creatinine levels were associated with a worse prognosis.

CONCLUSION

With strict methodology, HF is truly a disease of the elderly, with significant one-year mortality and morbidity consequences. Prognostic characteristics are reviewed.