Remote dielectric sensing detects pulmonary congestion in emergency patients with dyspnoea

Background

Immediate diagnosis of acute decompensated heart failure (ADHF) is essential in patients with dyspnoea. Remote Dielectric Sensing (ReDS), an electromagnetic non-invasive technology, estimates lung fluid content fast and observer-independently. In previous studies, ReDS discriminated congested heart failure patients from normal subjects with high accuracy. But not all ADHF patients have pulmonary interstitial congestion in the real world, and it is unknown if ReDS detects ADHF in consecutive patients with acute dyspnoea.

Purpose

To examine if ReDS can detect ADHF in consecutive dyspnoeic emergency patients and to compare ReDS with other diagnostic methods.

Method

This prospective observational study included consecutive patients with dyspnoea from the emergency departments. The exclusion criteria were age below 50 years, acute coronary syndrome, conditions prohibiting a supine CT scan, and no informed consent. We examined all patients immediately with ReDS, low-dose chest CT, echocardiogram, lung ultrasound (LUS), NT-proBNP, and Boston score. The Boston score used chest X-ray and clinical signs such as orthopnoea, jugular venous elevation, lung crackles and pedal oedema, and a score ≥8 equalled definite ADHF. A “LUS-score” ≥3 with at least 3 B-lines in one zone bilaterally equalled ADHF. ReDS values >35% lung fluid content were positive for pulmonary congestion, according to previous studies.

According to ESC guidelines, an expert panel adjudicated the ADHF diagnosis based on clinical signs, chest X-ray image, NT-proBNP, echocardiographic cardiac dysfunction (HFvhd, HFrEF, HFmrEF, HFpEF), and elevated LV filling pressure. Importantly, the panel was blinded to the ReDS values. For sub-analyses, we divided ADHF patients into a “CT-congested” ADHF subgroup if an independent chest CT showed interstitial congestion. We classified ADHF patients without congestion on CT, as the “mildly-congested” subgroup.

Results

97 included patients were examined within a median of 4.8 hours from admittance: 39 (40%) had ADHF, and 25 (26%) were ReDS-positive. ADHF patients had median LVEF 48%, NT-proBNP 347 pmol/l, and 85% had echocardiographic elevated LV filling pressure. ReDS detected ADHF with 46% sensitivity, 88% specificity, and 71% accuracy. The AUC for ReDS to detect ADHF (Figure 1), on a continuous scale, was similar to the Boston score (p=0.88) and the LUS score (p=0.74), but lower than NT-proBNP (p=0.02). The 21 (22%) CT-congested ADHF patients had higher ReDS values than the 18 (19%) mildly-congested ADHF patients (Figure 2, median 38% vs 30%, p<0.001). Furthermore, the mildly-congested ADHF patients had ReDS values similar to non-ADHF patients (median 30% vs 28%, p=0.36).

Conclusion

ReDS detects ADHF similarly to the Boston score and lung ultrasound but is inferior to NT-proBNP. This study suggests that ReDS primarily identifies CT-congested ADHF patients, but not the ADHF patients without interstitial congestion.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): This work was supported by the research fund of Bispebjerg University Hospital and Holger & Ruth Hesse's Mindefond. Sensible Medical Ltd made the ReDS device available for free and provided an unrestricted grant to specifically collect the ReDS measurements. The sponsors did not affect the statistical analyses, study design, data collection, or writing of the paper.

High-sensitive Troponin T is not associated with the progression of asymptomatic mild to moderate aortic stenosis: a post hoc substudy of the SEAS trial

Background

Aortic stenosis (AS) and coronary artery disease (CAD) share pathophysiological pathways, as reflected by frequent concomitant revascularization in patients undergoing aortic valve replacement (AVR). High-sensitive Troponin T (hsTnT) is a proven biomarker of cardiomyocyte overload and injury, and predicts postoperative mortality after AVR. However, it is unknown if hsTnT can predict AVR, mortality or ischemic coronary events (ICE) in asymptomatic AS patients.

Purpose

To investigate the hypothesis that increased hsTnT is associated with more severe AS and a higher risk of adverse outcomes in asymptomatic AS patients without overt CAD.

Methods

hsTnT concentrations were examined at baseline and after 1-year follow-up in 1739 asymptomatic AS patients enrolled in the randomized, double-blind Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study. The main inclusion criteria were: left ventricular (LV) ejection fraction >55%, transaortic maximal velocity between 2.5–4.0 m/s, and no history of CAD. The primary exposure variable was increased hsTnT (>14 pg/mL according to the assay manufacturer, Roche). This study's primary endpoint was a composite of competing risk outcomes: all-cause mortality as the first event, AVR without revascularization, and ICE (defined as myocardial infarction before AVR, PCI before or combined with AVR, or any CABG). Multivariable regression examined associations between hsTnT and clinical variables. Cox proportional hazards regression models were adjusted for age, sex, creatinine, LV mass index, mean aortic pressure gradient (Pmean) and stratified by center and lipid-lowering treatment. We analyzed outcomes during 5-year follow-up from baseline.

Results

At baseline, 453 (26.0%) patients had increased hsTnT and 302 (17.4%) had moderate-severe AS with a mean (SD) aortic valve area of 0.8 (0.2) cm2 and Pmean of 33.2 (8.8) mmHg. The median annual hsTnT change from baseline to year 1 was 0.8 pg/mL (IQR, −0.4 to 2.3), regardless of AS severity (P=0.08). In adjusted models, log(hsTnT at baseline) was associated with age, sex, creatinine, and LV mass index (all P<0.05), but not with AS severity (P=0.36). The incidence rate ratio for ICE (Figure 1) in patients with increased vs normal baseline hsTnT concentrations was 2.32 (95% CI, 1.72–3.11, P<0.001). In adjusted Cox regression, increased hsTnT was associated with an increased 5-year ICE risk (HR 1.64; 95% CI, 1.18–2.29, P=0.003), but neither with AVR without revascularization nor death (Figure 1).

Conclusion

In these asymptomatic AS patients without overt CAD, hsTnT is often normal and remains stable during 1 year of follow-up regardless of AS severity. Increased hsTnT is associated with CAD-related events, but neither to AS severity nor AVR without concomitant revascularization. This analysis does not support routine hsTnT measurement in asymptomatic AS to predict AVR related to AS progression, although hsTnT could improve the risk assessment for ICE.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Main sponsor (SEAS): Merck & Co Inc, Whitehouse Station, New JerseyBlood analysis sponsor: Roche Diagnostics International Ltd, Switzerland

Risk of pericardiac effusion after cardiac implantable electronic device implantation a nationwide study

Funding Acknowledgements

Type of funding sources: None.

Background

Procedural pericardiac effusion (PE) is considered a major complication to implantation of cardiac implantable electronic devices (CIED), including permanent pacemakers (PM), cardiac resynchronization therapy devices with defibrillators (CRT-D) or without (CRT-P), and implantable cardioverter defibrillators (ICD), as it can cause life threatening cardiac tamponade. Very little is known about risk factors for procedural PE.

Aim

To identify the patient- and procedure related risk factors associated with clinically relevant procedural PE.

Methods & Results

This is a nationwide retrospective observational cohort study based on data on 51.599 patients from the Danish Pacemaker Register. Included were all Danish patients who received their first PM, CRT or ICD from 2000 – 2018. Procedural PE was defined related to the invasive procedure if it occurred within 1 months after the invasive procedure and no cancer was diagnosed before the procedure. Pre-specified risk factors, including sex, age, year, implantation center-type and device type were analyzed by multivariable logistic regression models to estimate the association with PE. A total of 78 (0.2%) patients were diagnosed with procedural PE, with a median age of 73 years and 43% were females. In adjusted logistic regression analysis age > 70, heart failure [aOR 1.64 (1.01;2.67)], ischemic heart disease [aOR 1.84 (1.13;2.99)], direct oral anticoagulation [aOR 1.77 (1.13–2.77.)], amiodarone use [aOR 3.03 (1.75–5.22)], beta blocking agent [aOR 2.26 (1.23 –4.14)], university hospitals [aOR 2.59 (1.18 –5.67)] and PM implantation [aOR 3.38 (1.77;6.45)], were associated with PE.

Conclusion

Procedural PE is a rare complication after CIED implantation in Denmark. Importantly most of the risk factors for PE are modifiable. Optimizing the modifiable risk factors may reduce the risk of complication.

4329Mega-studies in heart failure, effect dilution in examination of new therapies

Aims

All phase 3 studies in patients with acute heart failure (AHF) and HF with preserved ejection fraction (HFpEF) have failed in the last decades. We explore the likelihood that the negative results are due to chance and/or to study size and dilution of statistical power.

Methods and results

First, using simulations, we examined the probability that a positive finding in phase 2 would result in studying truly effective drugs in phase 3. We simulated phase 2 studies under six scenarios where the range of true relative risk (RR) for an outcome of interest varied from 0.5 (major benefit) to 1.15 (some harm). The proportion of simulated studies where the RR <0.8 (we assumed that a 20% or greater risk reduction reflects an effective drug) ranged from 6% to 42% across the six scenarios studied. To further simulate “real life” clinical research, we simulated a continuous surrogate outcome that was linearly related to the true RR in each simulation of each scenario. Regardless of criteria considered for a positive phase 2 trial, results suggest that even in our worst-case scenario, where overall only 6% of drugs taken into phase 2 are effective, roughly 20% of phase 3 studies, if appropriately powered, should have yielded positive results. Given this, we then explored study size in AHF research, as a potential explanation for the high failure rate in these studies. Comparison of published phase 2 and 3 clinical trials with registries in AHF suggest that populations in both large and small trials differ from “real life”. Meta-regression models suggest that both control event rates, and in the serelaxin program as an example, treatment effects, decline with increasing study size greatly reducing power (figure). This effect dilution might be explained by an increasing proportion of patients enrolled in studies who cannot benefit from the study drug.

Figure 1. Power at two-sided 0.05 significance level to detect an effect size of hazard ratio of 0.65 (left) or 0.8 (right) with a placebo event rate of 10% (top) and 20% (bottom) at N=100 at various treatment effect dilutions with increasing sample size.

Conclusion

These data suggest that it is unlikely that the very high rate of negative AHF phase III trials can be explained by chance alone. Potentially, our tendency to increase sample size does not necessarily increase statistical power, due to more heterogenous populations leading to reduced event rates and treatment effects.

P3779NT-proBNP adds incremental predictive information on incident atrial fibrillation in patients with asymptomatic aortic stenosis

Background

Incident atrial fibrillation (AF) marks an adverse shift in the prognosis of patients with aortic stenosis (AS). Identifying risk factors for AF is therefore of paramount importance for timely intervention in patients with AS. In patients without AS, brain natriuretic peptides (BNP) is a well-established biomarker for left ventricular pressure overload on the pathway to heart failure and atrial fibrillation. However, a potential role of NT-proBNP to predict risk of new-onset AF in asymptomatic patients with mild to moderate AS is not well studied.

Methods

We included 1,434 patients with mild to moderate AS from the SEAS Study (Simvastatin and Ezetimibe in Aortic Stenosis) without AF or clinically overt heart failure at baseline. The primary endpoint for this substudy was time to incident AF, as determined by the first annual in-study 12-lead ECG with AF. Multivariable Cox model were adjusted for other important predictors of incident AF as selected by Bayesian statistics. Fine and Gray competing risk regression was used to evaluate the influence of all-cause mortality on selected predictor variables of incident AF.

Results

During a median follow-up of 4.3 years (range 0.1–6.9 years), incident AF occurred in 114 (6.1%) patients (13.8 per 1,000 person-years of follow-up), who at baseline were older (69±10 vs. 67±10 years, p<0.001), had larger systolic left atrial diameter (46±24 vs. 34±18 mm, p<0.001) and higher NT-proBNP level (286 [132; 613] vs. 154 [82; 297] pg/ml, p<0.001); but same left ventricular ejection fraction (66±6 mm vs. 67±6, p=0.4). In multivariable Cox regression, adjusted for age, circumferential end-systolic stress, left atrial volume and ECG PR interval, Ln(NT-proBNP) was associated with higher risk of new-onset AF (HR: 1.9 [95% CI: 1.6–2.3], p<0.001). Similar results were found when using Fine and Gray estimates with all-cause mortality (HR: 2.0 [95% CI: 1.7–2.4], p<0.001 (Figure, panel A). NT-proBNP level added incremental predictive information on incident AF over the other important, as selected by Bayesian statistics, predictor variables (C-index 0.81, p<0.001, Figure, panel B). There was no interaction with aortic valve area (p>0.05).

Figure 1

Conclusions

In patients with asymptomatic aortic stenosis and sinus rhythm at baseline, NT-proBNP levels were significantly higher in patients who subsequently developed AF. NT-proBNP significantly improved prognostic information of incident AF over other important predictor variables. This supports the notion that incident AF is a marker of left ventricular pressure overload and possibly a novel marker of timely intervention with aortic valve replacement.

Hyponatraemia at hospital admission is a predictor of overall mortality

BACKGROUND

Hyponatraemia is a prognostic marker of increased mortality and morbidity in selected groups of hospitalised patients. The aim of the present study was to examine the prevalence and prognostic significance of hyponatraemia at hospital admission in an unselected population with a broad spectrum of medical and surgical diagnoses.

METHODS

Consecutive patients >40 years of age admitted to a general district hospital in Greater Copenhagen between 1 April 1998 and 31 March 1999. Median follow-up time was 5.16 years (range 0-4372 days). Plasma sodium measurements were available in 2960 patients, and hyponatraemia defined as P-Na(+) <137 mmol/L at hospital admission was present in 1105 (37.3 %) patients.

RESULTS

One-year mortality was higher for hyponatraemic patients than for normonatraemic patients: 27.5% versus 17.7%. Moreover, hyponatraemia was an independent predictor of short and long-term all-cause mortality after 1 year and after the entire observation period respectively: hazard ratio (HR) 1.6 (95 % confidence interval (CI) 1.4-1.9, P < 0.0001) and HR 1.4 (95 % CI 1.3-1.6, P < 0.0001). Patients with hyponatraemia had longer hospitalisations than patients with normonatraemia: 7.6 (±0.38) days vs 5.6 (±0.21) days, P < 0.001. There was no interaction between hyponatraemia at admission and any admission diagnoses (P > 0.05 for all interaction analyses).

CONCLUSION

Hyponatraemia is associated with increased all-cause mortality and longer admission length independently of diagnosis and clinical variables.

Pentraxin-3 level at admission is a strong predictor of short-term mortality in a community-based hospital setting

BACKGROUND

The pattern recognition molecule pentraxin-3 (PTX3) is a novel potential marker of prognosis, as elevated levels are associated with both disease severity and mortality in patients with a wide range of conditions. However, the usefulness of PTX3 as a prognostic biomarker in a general hospital setting is unknown.

PATIENTS AND METHODS

The study cohort consisted of 1326 unselected, consecutive patients (age >40 years) admitted to a community hospital in Copenhagen, Denmark. Patients were followed until death or for a median of 11.5 years after admission. The main outcome measure was all-cause mortality. Serum samples collected from patients at admission and from 192 healthy control subjects were quantified for PTX3 level by enzyme-linked immunosorbent assay.

RESULTS

PTX3 was elevated in patients (median 3.7 ng mL(-1) , range 0.5-209.8) compared with healthy nonhospitalized subjects (median 3.5 ng mL(-1) , range 0.0-8.3; P = 0.0003). Elevated PTX3 levels, defined as above the 95th percentile of the concentration in healthy subjects, were associated with increased overall mortality during the study (P < 0.0001). This increase in mortality was greatest in the short term, with an unadjusted hazard ratio (HR) of 6.4 [95% confidence interval (CI) 3.8-11.0] at 28 days after admission, compared to 1.7 (95% CI 1.4-2.0) at the end of follow-up. These results were still significant after adjustment for age, gender and glomerular filtration rate: adjusted HR of 5.0 (95% CI 2.9-8.8) and 1.4 (95% CI 1.2-1.8), respectively.

CONCLUSION

These results suggest that PTX3 could be a widely applicable marker of short-term mortality in hospitalized patients and may be useful in the initial risk stratification.

Carnitine levels in skeletal muscle, blood, and urine in patients with primary carnitine deficiency during intermission of L-carnitine supplementation

BACKGROUND

Primary carnitine deficiency (PCD) is a disorder of fatty acid oxidation with a high prevalence in the Faroe Islands. Only patients homozygous for the c.95A>G (p.N32S) mutation have displayed severe symptoms in the Faroese patient cohort. In this study, we investigated carnitine levels in skeletal muscle, plasma, and urine as well as renal elimination kinetics before and after intermission with L-carnitine in patients homozygous for c.95A>G.

METHODS

Five male patients homozygous for c.95A>G were included. Regular L-carnitine supplementation was stopped and the patients were observed during five days. Blood and urine were collected throughout the study. Skeletal muscle biopsies were obtained at 0, 48, and 96 h.

RESULTS

Mean skeletal muscle free carnitine before discontinuation of L-carnitine was low, 158 nmol/g (SD 47.4) or 5.4% of normal. Mean free carnitine in plasma (fC0) dropped from 38.7 (SD 20.4) to 6.3 (SD 1.7) μmol/L within 96 h (p < 0.05). Mean T 1/2 following oral supplementation was approximately 9 h. Renal reabsorption of filtered carnitine following oral supplementation was 23%. The level of mean free carnitine excreted in urine correlated (R (2) = 0.78, p < 0.01) with fC0 in plasma.

CONCLUSION

Patients homozygous for the c.95A>G mutation demonstrated limited skeletal muscle carnitine stores despite long-term high-dosage L-carnitine supplementation. Exacerbated renal excretion resulted in a short T 1/2 in plasma carnitine following the last oral dose of L-carnitine. Thus a treatment strategy of minimum three daily separate doses of L-carnitine is recommended, while intermission with L-carnitine treatment might prove detrimental.

Cardiovascular risk in patients with sleep apnoea with or without continuous positive airway pressure therapy: follow-up of 4.5 million Danish adults

BACKGROUND

The prognostic significance of age and continuous positive airway pressure (CPAP) therapy on cardiovascular disease in patients with sleep apnoea has not been assessed previously.

METHODS

Using nationwide databases, the entire Danish population was followed from 2000 until 2011. First-time sleep apnoea diagnoses and use of CPAP therapy were determined. Incidence rate ratios (IRRs) of ischaemic stroke and myocardial infarction (MI) were analysed using Poisson regression models.

RESULTS

Amongst 4.5 million individuals included in the study, 33 274 developed sleep apnoea (mean age 53, 79% men) of whom 44% received persistent CPAP therapy. Median time to initiation of CPAP therapy was 88 days (interquartile range 34-346). Patients with sleep apnoea had more comorbidities compared to the general population. Crude rates of MI and ischaemic stroke were increased for sleep apnoea patients (5.4 and 3.6 events per 1000 person-years compared to 4.0 and 3.0 in the general population, respectively). Relative to the general population, risk of MI [IRR 1.71, 95% confidence interval (CI) 1.57-1.86] and ischaemic stroke (IRR 1.50, 95% CI 1.35-1.66) was significantly increased in patients with sleep apnoea, in particular in patients younger than 50 years (IRR 2.12, 95% CI 1.64-2.74 and IRR 2.34, 95% CI 1.77-3.10, respectively). Subsequent CPAP therapy was not associated with altered prognosis.

CONCLUSIONS

Sleep apnoea is associated with increased risk of ischaemic stroke and MI, particularly in patients younger than 50 years of age. CPAP therapy was not associated with a reduced rate of stroke or MI.

The inflammatory biomarker YKL-40 at admission is a strong predictor of overall mortality

OBJECTIVES

YKL-40 is an inflammatory biomarker associated with disease activity and mortality in patients with diseases characterized by inflammation and tissue remodelling. The aim of this study was to describe the prognostic value of YKL-40 in an unselected patient population.

DESIGN

In consecutive patients admitted to hospital during a 1-year period, blood was collected and information regarding final diagnosis and mortality was collected. Median follow-up time was 11.5 years.

SETTING

District hospital, Copenhagen, Denmark.

PATIENTS

A total of 1407 patients >40 years of age were admitted acutely.

MAIN OUTCOME MEASURE

All-cause mortality.

RESULTS

Median YKL-40 was increased in patients (157 μg L(-1) , range 13-7704 μg L(-1) ) compared to healthy controls (40 μg L(-1) , range 29-58 μg L(-1) ; P < 0.001). Patients with YKL-40 in the highest quartile had a hazard ratio (HR) of 7.1 [95% confidence interval (CI) 4.2-12.0] for all-cause mortality in the first year and 3.4 (95% CI 2.8-4.2) in the total study period, compared to those in the lowest quartile (HR = 1). The HR for death for all patients with YKL-40 above the normal age-corrected 95th percentile was 2.1 (95% CI 1.6-2.7) after 1 year and 1.5 (95% CI 1.3-1.7) during the total study period, compared to patients with YKL-40 below the age-corrected 95th percentile. The results of multivariable analysis showed that YKL-40 was an independent biomarker of mortality; this was most significant in the first year. YKL-40 was a marker of prognosis in all disease categories. The HR for death was increased in patients with YKL-40 above the normal age-corrected 95th percentile in healthy subjects independent of type of disease (all P < 0.001).

CONCLUSION

The level of YKL-40 at admission is a strong predictor of overall mortality, independent of diagnosis and could be useful as a biomarker in the acute evaluation of all patients.

Neuroendocrine testing in community patients with heart disease: plasma N-terminal proatrial natriuretic peptide predicts morbidity and mortality stronger than catecholamines and heart rate variability

BACKGROUND

Patients with heart disease are at risk of developing congestive heart failure (CHF). Neurohormonal activation may make an important contribution.

AIM

In stable heart patients from primary care, to examine neuroendocrine markers of cardiac performance for the association to cardiac dysfunction, morbidity and mortality.

METHODS

Plasma N-terminal atrial natriuretic peptide (N-ANP), catecholamines, 24-h ECG and blood pressure, serum urea and creatinine, echocardiography, chest X-ray and physical examination were performed. Death was recorded during 5 to 7 years of follow-up.

RESULTS

The study included 56 patients. Mean age was 71 years, 54% were men, 43% had clinical signs of CHF, 39 + 52 + 9% were in NYHA I + II + III, 34% had echocardiographic cardiac dysfunction, and 18 died during follow-up. N-ANP was related to all subtypes of cardiac dysfunction (p < 0.05). Catecholamines and premature ventricular captures (PVC) were related to valvular and systolic dysfunction, but heart rate variability and dipping blood pressure were not (p > 0.05). On multivariate analyses only, N-ANP and PVC were associated with clinical signs of CHF, echocardiographic cardiac dysfunction, and mortality (p < 0.05).

CONCLUSIONS

Plasma N-ANP was stronger than catecholamines and variables of 24-h monitoring (blood pressure and electrocardiogram) in predicting morbidity and mortality, thereby supporting the use of cardiac natriuretic peptides (i.e. N-ANP, BNP, or N-BNP) as the most valuable biomarker in community patients at risk of CHF.

C-reactive protein, heart rate variability and prognosis in community subjects with no apparent heart disease

OBJECTIVES

Increased C-reactive protein (CRP) and reduced heart rate variability (HRV) both indicate poor prognosis. An inverse association between HRV and CRP has been reported, suggesting an interaction between inflammatory and autonomic systems. However, the prognostic impact of this interaction has not been studied. We thus investigated the prognostic impact of CRP, HRV and their combinations.

DESIGN

Population-based study.

SUBJECTS

A total of 638 middle-aged and elderly subjects with no apparent heart disease from community.

METHODS

All were studied by clinical and laboratory examinations, and 24-h Holter monitoring. Four time domain measures of HRV were studied. All were prospectively followed for up to 5 years.

RESULTS

Mean age was 64 years (55-75). During the follow-up, 46 total deaths and 11 cases of definite acute myocardial infarction were observed. Both CRP and three of four HRV measures were significantly associated with increased rate of death or myocardial infarction. In a Cox model with CRP >or=2.5 microg mL(-1), standard deviation for the mean value of the time between normal complexes <or=100 ms, and their combination, hazard ratio and 95% CI for subjects with both abnormalities was 3.20 (1.55-6.56), P = 0.0016, and for subjects with either abnormality 1.63(0.83-3.20), P = 0.15, after adjustment for conventional risk factors. The combination of CRP and other measures of HRV gave similar results. This indicates an interaction between CRP and HRV with a synergistic effect.

CONCLUSIONS

The combination of CRP and HRV or heart rate (HR) predicts death and myocardial infarction with synergism, indicating interaction between inflammatory and autonomic systems with a prognostic significance.

N-terminal proBNP and mortality in hospitalised patients with heart failure and preserved vs. reduced systolic function: data from the prospective Copenhagen Hospital Heart Failure Study (CHHF)

Preserved systolic function among heart failure patients is a common finding, a fact that has only recently been fully appreciated. The aim of the present study was to examine the value of NT-proBNP to predict mortality in relation to established risk factors among consecutively hospitalised heart failure patients and secondly to characterise patients in relation to preserved and reduced systolic function.

MATERIAL

At the time of admission 2230 consecutively hospitalised patients had their cardiac status evaluated through determinations of NT-proBNP, echocardiography, clinical examination and medical history. Follow-up was performed 1 year later in all patients.

RESULTS

161 patients fulfilled strict diagnostic criteria for heart failure (HF). In this subgroup of patients 1-year mortality was approximately 30% and significantly higher as compared to the remaining non-heart failure population (approx. 16%). Using univariate analysis left ventricular ejection fraction (LVEF), New York Heart Association classification (NYHA) and plasma levels of NT-proBNP all predicted mortality independently. However, regardless of systolic function, age and NYHA class, risk-stratification was provided by measurements of NT-proBNP. Having measured plasma levels of NT-proBNP, LVEF did not provide any additional prognostic information on mortality among heart failure patients (multivariate analysis).

CONCLUSION

The results show that independent of LVEF, measurements of NT-proBNP add additional prognostic information. It is concluded that NT-proBNP is a strong predictor of 1-year mortality in consecutively hospitalised patients with heart failure with preserved as well as reduced systolic function.

Cross sectional study estimating prevalence of heart failure and left ventricular systolic dysfunction in community patients at risk

OBJECTIVE

To examine a general practice population to measure the prevalence of signs and symptoms of heart failure (SSHF) and left ventricular systolic dysfunction (LVSD).

DESIGN

Cross sectional screening study in three general practices followed by echocardiography.

SETTING AND PATIENTS

All patients ⩾ 50 years in two general practices and ⩾ 40 years in one general practice were screened by case record reviews and questionnaires (n = 2158), to identify subjects with some evidence of heart disease. Among these, subjects were sought who had SSHF (n = 115). Of 357 subjects with evidence of heart disease, 252 were eligible for examination, and 126 underwent further cardiological assessment, including 43 with SSHF.

MAIN OUTCOME MEASURES

Prevalence of SSHF as defined by a modified Boston index, LVSD defined as an indirectly measured left ventricular ejection fraction ⩽ 0.45, and numbers of subjects needing an echocardiogram to detect one case with LVSD.

RESULTS

SSHF afflicted 0.5% of quadragenarians and rose to 11.7% of octogenarians. Two thirds were handled in primary care only. At ⩾ 50 years of age 6.4% had SSHF, 2.9% had LVSD, and 1.9% (95% confidence interval 1.3% to 2.5%) had both. To detect one case with LVSD in primary care, 14 patients with evidence of heart disease without SSHF and 5.5 patients with SSHF had to be examined.

CONCLUSION

SSHF is extremely prevalent in the community, especially in primary care, but more than two thirds do not have LVSD. The number of subjects with some evidence of heart disease needing an echocardiogram to detect one case of LVSD is 14.

Cross sectional study estimating prevalence of heart failure and left ventricular systolic dysfunction in community patients at risk

OBJECTIVE

To examine a general practice population to measure the prevalence of signs and symptoms of heart failure (SSHF) and left ventricular systolic dysfunction (LVSD).

DESIGN

Cross sectional screening study in three general practices followed by echocardiography.

SETTING AND PATIENTS

All patients >/= 50 years in two general practices and >/= 40 years in one general practice were screened by case record reviews and questionnaires (n = 2158), to identify subjects with some evidence of heart disease. Among these, subjects were sought who had SSHF (n = 115). Of 357 subjects with evidence of heart disease, 252 were eligible for examination, and 126 underwent further cardiological assessment, including 43 with SSHF.

MAIN OUTCOME MEASURES

Prevalence of SSHF as defined by a modified Boston index, LVSD defined as an indirectly measured left ventricular ejection fraction </= 0.45, and numbers of subjects needing an echocardiogram to detect one case with LVSD.

RESULTS

SSHF afflicted 0.5% of quadragenarians and rose to 11.7% of octogenarians. Two thirds were handled in primary care only. At >/= 50 years of age 6.4% had SSHF, 2.9% had LVSD, and 1.9% (95% confidence interval 1.3% to 2.5%) had both. To detect one case with LVSD in primary care, 14 patients with evidence of heart disease without SSHF and 5.5 patients with SSHF had to be examined.

CONCLUSION

SSHF is extremely prevalent in the community, especially in primary care, but more than two thirds do not have LVSD. The number of subjects with some evidence of heart disease needing an echocardiogram to detect one case of LVSD is 14.

Risk assessment of left ventricular systolic dysfunction in primary care: cross sectional study evaluating a range of diagnostic tests

OBJECTIVES

To assess the probability of left ventricular systolic dysfunction without echocardiography in patients from general practice.

DESIGN

Cross sectional study using multivariate regression models to examine the relation between clinical variables and left ventricular systolic dysfunction as determined by echocardiography.

SETTING

Three general practices in Copenhagen.

SUBJECTS

2158 patients aged >40 years were screened by questionnaires and case record reviews; 357 patients with past or present signs or symptoms of heart disease were identified, of whom 126 were eligible for and consented to examination.

MAIN OUTCOME MEASURES

Clinical variables that were significantly (P<0.05) related to ejection fraction </=0.45 and their predictive value for left ventricular systolic dysfunction.

RESULTS

15 patients (12%) had left ventricular systolic dysfunction. The prevalence was significantly related to three questions: does the electrocardiogram have Q waves, left bundle branch block, or ST-T segment changes? (P=0.012); is resting supine heart rate greater than the simultaneous diastolic blood pressure? (P=0.002); and is plasma N-terminal atrial natriuretic peptide>0.8 nmol/l? (P=0.040)? Only one of 60 patients with a normal electrocardiogram had systolic dysfunction (2%, 95% confidence interval 0% to 9%) regardless of response to the other two questions. The risk of dysfunction was appreciable in patients with a yes answer to two or three questions (50%, 27% to 73%).

CONCLUSIONS

A normal electrocardiogram implies a low risk of left ventricular systolic dysfunction. Patients can be identified for echocardiography on the basis of an abnormal electrocardiogram combined with increased natriuretic peptide concentration or a heart rate greater than diastolic blood pressure, or both.

[Diagnosis of acute myocardial infarction in Denmark]

The introduction of new biochemical markers for myocardial damage in the recent years and different application of these methods in different centres may have an impact on the diagnostic criteria for acute myocardial infarction (AMI). By means of a questionnaire we studied the diagnostic criteria for AMI in relation to the use of different biochemical markers among 78 Danish hospitals. There were large variations with regard to the choice of cardiac markers and diagnostic values for different markers. CK-B is the cardiac marker mostly used followed by CK-MB. Troponin-T test was used by about 20% of the centres. Many centres are planning to use CK-MB and Troponin-T test. A common national and international policy for diagnosis of AMI in relation to different cardiac markers should reduce these improper differences.

Precision and accuracy of a noninvasive inert gas washin method for determination of cardiac output in men

Stout et al. (J. Appl. Physiol. 38:913-918, 1975) suggested an open-circuit multibreath (MB) inert gas method for determining pulmonary capillary blood flow (Qc) in anesthetized dogs receiving artificial ventilation. In the present work we investigated the accuracy and reproducibility of the MB method in nine healthy human subjects at spontaneous ventilation, and we compared the MB method with the inert gas rebreathing (RB) method. Qc was calculated at rest and during exercise at 50 or 100 W, and experimental errors were evaluated in computer simulations of a two-alveoli lung model. The calculated mean Qc values of the MB method were 5.56 +/- 1.23 (SD), 10.02 +/- 0.78, and 13.2 +/- 0.84 l/min, and the mean difference (MB Qc - RB Qc) was not significantly different (P > 0.05). The variation in Qc of the MB method was found to be significantly larger than that in Qc of the RB method (P < 0.01). Random measurement errors and uneven distribution of ventilation contributed to the experimental errors. We conclude that the MB method is inferior to the RB method but that the MB method may be useful under exercise conditions.

Nonlinear curve fitting improves noise sensitivity of the single-breath method for estimation of cardiac output

In a recent theoretical study, Srinivasan (10) presented a new nonlinear curve fitting algorithm for computing pulmonary blood flow by the single-breath method. The results obtained with the new algorithm showed a considerably lower sensitivity of the estimated pulmonary blood flow to experimental noise than with the linear curve fitting technique reported previously by Grønlund (5). In the present study, we have compared the linear and the nonlinear algorithms using computer simulations and experimental single-breath data. The results showed only a small difference between the two methods. Further, we showed that the difference between the noise sensitivities obtained by Grønlund (5) and Srinivasan (10) can be explained almost entirely by a difference between the models used to simulate experimental noise.