Clinical outcome of patients with heart failure and preserved left ventricular function

Rapid and non-invasive diagnosis of hyperkalemia in patients with systolic myocardial failure using a model based on machine learning algorithms

Background

Hyperkalemia is a potentially life-threatening electrolyte disturbance that if not diagnosed on time may lead to devastating conditions and sudden cardiac death. Blood sampling for potassium level checks is time-consuming and can delay the treatment of severe hyperkalemia on time. So, we propose a non-invasive method for correct and rapid hyperkalemia detection.

Methods

The cardiac signal of patients referred to the Pediatrics Emergency room of Shahid Rejaee Hospital was measured by a 12-lead Philips electrocardiogram (ECG) device. Immediately, the blood samples of the patients were sent to the laboratory for potassium serum level determination. We defined 16 features for each cardiac signal at lead 2 and extracted them automatically using the algorithm developed. With the help of the principal component analysis (PCA) algorithm, the dimension reduction operation was performed. The algorithms of decision tree (DT), random forest (RF), logistic regression, and support vector machine (SVM) were used to classify serum potassium levels. Finally, we used the receiver operation characteristic (ROC) curve to display the results.

Results

In the period of 5 months, 126 patients with a serum level above 4.5 (hyperkalemia) and 152 patients with a serum potassium level below 4.5 (normal potassium) were included in the study. Classification with the help of a RF algorithm has the best result. Accuracy, Precision, Recall, F1, and area under the curve (AUC) of this algorithm are 0.71, 0.87, 0.53, 0.66, and 0.69, respectively.

Conclusions

A lead2-based RF classification model may help clinicians to rapidly detect severe dyskalemias as a non-invasive method and prevent life-threatening cardiac conditions due to hyperkalemia.

Serum albumin and the short-term mortality in individuals with congestive heart failure in intensive care unit: an analysis of MIMIC

Decreased albumin levels are common in congestive heart failure (CHF), but little is known about its role in mortality risk in CHF. This study developed a cohort prediction model based on 7121 individuals with heart failure to evaluate the short-term mortality and prognostic role of albumin in patients with CHF. The cohort was from intensive care unit between 2001 and 2012 in a publicly available clinical database in intensive care called MIMIC III. We used a generalized additive model to determine the nonlinear correlation between serum albumin and 14th day, 28th day and 90th day all-cause mortality in patients with heart failure. The results showed that serum albumin is an independent risk factor for 14th, 28th and 90th day all-cause mortality, and has a linear relationship with all-cause mortality in congestive heart failure. Cox regression analysis using restricted cubic spline with albumin as continuous parameter showed that the decrease of albumin level is directly related to the increase of mortality (14th day mortality: hazard ratio [HR], 0.65 [95% CI, 0.58 to 0.73]); 28th day mortality: HR, 0.56 [95% CI, 0.51 to 0.63]; 90th day mortality: HR, 0.52 [95% CI, 0.47 to 0.57]; P for trend < 0.001). The multivariate adjusted association between albumin (as a continuous variable) and all-cause mortality on the 90th days is mixed by ARDS [HR, 0.64, 95% CI (0.47–0.87), P = 0.005]. The all-cause mortality on the 90th day predicted better clinical results with the all-cause mortality on the 14th day.

Electrocardiographic characteristics in patients with heart failure and normal ejection fraction: A systematic review and meta-analysis

BACKGROUND

Little is known about ECG abnormalities in patients with heart failure and normal ejection fraction (HeFNEF) and how they relate to different etiologies or outcomes.

METHODS AND RESULTS

We searched the literature for peer-reviewed studies describing ECG abnormalities in HeFNEF other than heart rhythm alone. Thirty five studies were identified and 32,006 participants. ECG abnormalities reported in patients with HeFNEF include atrial fibrillation (prevalence 12%-46%), long PR interval (11%-20%), left ventricular hypertrophy (LVH, 10%-30%), pathological Q waves (11%-18%), RBBB (6%-16%), LBBB (0%-8%), and long JTc (3%-4%). Atrial fibrillation is more common in patients with HeFNEF compared to those with heart failure and reduced ejection fraction (HeFREF). In contrast, long PR interval, LVH, Q waves, LBBB, and long JTc are more common in patients with HeFREF. A pooled effect estimate analysis showed that QRS duration ≥120 ms, although uncommon (13%-19%), is associated with worse outcomes in patients with HeFNEF.

CONCLUSIONS

There is high variability in the prevalence of ECG abnormalities in patients with HeFNEF. Atrial fibrillation is more common in patients with HeFNEF compared to those with HeFREF. QRS duration ≥120 ms is associated with worse outcomes in patients with HeFNEF. Further studies are needed to address whether ECG abnormalities correlate with different phenotypes in HeFNEF.

Low serum albumin: A significant predictor of reduced survival in patients with chronic heart failure

Background

Low serum albumin is common in patients with chronic heart failure (HF).

Hypothesis

Albumin may have an impact on clinical outcome in HF. We evaluated the effect of albumin levels on clinical outcome in a real‐world cohort of patients with HF.

Methods

All patients with HF at a health maintenance organization were followed for cardiac‐related hospitalizations and death.

Results

A total of 5779 HF patients were included in the study; mean follow‐up was 576 days; median serum albumin was 4.0 g/dL (interquartile range 3.7‐4.2), and 12% of the patients had hypoalbuminemia (albumin<3.5 g/dL). Low albumin was associated with increasing age, higher urea and C‐reactive protein, lower sodium, hemoglobin, iron, less treatment with angiotensin‐converting enzyme inhibitor or angiotensin receptor blocker, reduced right ventricular function, and pulmonary hypertension. Cox regression analysis after adjustment for significant predictors demonstrated that decreasing quartiles of albumin was significantly associated with mortality: Lowest quartile compared to highest: hazard ratio (HR) 5.74, 95% confidence interval (CI) 4.08 to 8.07, P < 0.001. Cox regression analysis of albumin as a continuous parameter using restricted cubic splines after adjustment for significant parameters demonstrated that reduced albumin levels were directly associated with increased mortality (P < 0.001 for the adjusted model). Decreasing quartiles of albumin were also a significant predictor of increased cardiac‐related hospitalizations. A decrease in albumin on follow‐up was an independent predictor of increased mortality by Cox regression analysis: HR 2.58, 95% CI 2.12 to 3.14, P < 0.001.

Conclusions

Low albumin provides important information regarding several detrimental processes in HF and is a significant predictor of a worse outcome in these patients.

Influence of potassium levels on one-year outcomes in elderly patients with acute heart failure

BACKGROUND

Abnormal serum potassium levels (K⁺) in patients with heart failure (HF) relate to worse prognosis. We evaluated whether admission K⁺ levels predict 1-year outcomes in elderly patients admitted for acute HF.

METHODS

We evaluated 2865 patients aged >74 years from the RICA Spanish Heart Failure Registry, classified according to admission serum K⁺ levels: hyperkalemia (>5.5 mmol/L), normokalemia (3.5-5.5 mmol/L) and hypokalemia (<3.5 mmol/L). We explored whether K⁺ levels were significantly associated with one-year all-cause mortality or hospital readmission and their combination.

RESULTS

Mean admission K⁺ value was 4.3 ± 0.6 mmol/L; 97 patients (3.38%) presented with hyperkalemia and 174 (6.06%) with hypokalemia. Overall, 43% of the patients died or were readmitted for HF during the follow-up period; the risk was higher for those with hyperkalemia (59% vs 41% in hypokalemic patients). The HR for one-year mortality was 1.43 (p = .073) and 1.67 for readmissions (p = .007) when K⁺ was >5.5 mmol/L and 1.08 (p = .618) and 0.90 (p = .533) respectively for K⁺ < 3.5 mmol/L. The HR for the combined outcome was 1.59 (1.19-2.13); p = .002 in hyperkalemic patients and 0.96 (0.75-1.23); p = .751in hypokalemic patients. Multivariate analysis showed a significant association of admission K⁺ values >5.5 mmol/L with the combined outcome of mortality and readmission (HR 1.15 [95% CI 1.04-1.27], p = .008).

CONCLUSION

In patients hospitalized for decompensated HF, admission hyperkalemia predicts a higher mid-term risk for HF readmission and mortality, probably related to the significant higher risk of readmission.

High comorbidity, measured by the Charlson Comorbidity Index, associates with higher 1-year mortality risks in elderly patients experiencing a first acute heart failure hospitalization

BACKGROUND

Comorbidity is related to poor health results in chronic heart failure (HF).

AIMS

The purpose of the study was to assess whether a high Charlson Comorbidity Index score (CCI) relates to 1 year mortality after a first hospitalization for acute HF (AHF).

METHODS

We reviewed the medical records of 897 patients > 65 years of age admitted within a two-year period because of a first episode of AHF. We analyzed two groups: low (CCI ≤ 2) and high (CCI > 2) comorbidity.

RESULTS

Patients' mean CCI was 2.2 ± 1.7; 344 patients (38.35%) had a CCI > 2. 1-year all-cause mortality rate in the high comorbidity group was 32.6%, worse than that among low comorbidity group patients (23.7%, p = 0.002). Cox multivariate analysis identified a CCI > 2 as an independent risk factor for 1-year mortality (p = 0.002; HR: 1.525; CI 95% 1.161-2.003), along with older age, history of arterial hypertension, and higher admission heart rate and serum potassium values. Analyzing CCI as a continuous variable, the association remained is also significant (p = 0.0001; HR 1.145; CI 95% 1.069-1.854).

CONCLUSIONS

Higher global comorbidity (CCI > 2) at the time of a first hospitalization because of AHF is an independent predictor of mid-term post-discharge mortality among elderly HF patients.

Serum Potassium Levels and Outcome in Patients With Chronic Heart Failure

Potassium levels are often abnormal in patients with heart failure (HF) and have a detrimental effect on clinical outcome. We evaluated potassium levels in a real-world cohort of patients with HF and its effect on mortality. All patients with a diagnosis of HF at a health maintenance organization were evaluated and followed for cardiac-related hospitalizations and death. The cohort consisted of 6,073 patients with HF. Mean potassium levels were 4.57 ± 0.53 mmol/L. Most patients (68%) had potassium levels in the normal range (4.0 to 5.0 mmol/L). High-normal potassium levels (5.0 to 5.5) were present in 17% of the patients, low potassium levels (<4.0) in 11%, and hyperkalemia (K ≥5.5) in 4%. Mean follow-up was 576 days. The overall mortality rate during this period was 14%. Survival rate by Kaplan-Meier analysis demonstrated that hypokalemia (K ≤3.5) was associated with the lowest survival rate. Survival was highest in patients with high-normal potassium levels. Cox regression analysis after adjustment for significant predictors including co-morbidities and standard HF drug therapies demonstrated that high-normal potassium levels were independently associated with reduced mortality compared with normal reference levels (hazard ratio 0.78, 95 confidence interval [CI] 0.64 to 0.95, p = 0.01). Subgroup analysis showed improved outcome with high-normal potassium levels in patients with reduced renal function, spironolactone, and loop diuretic therapy. In conclusion, potassium levels in the high-normal range appear to be safe and are associated with an improved outcome in patients with HF.

Is heart rate a risk marker in patients with chronic heart failure and concomitant atrial fibrillation? Results from the MAGGIC meta-analysis

AIM

To investigate the relationship between heart rate and survival in patients with heart failure (HF) and coexisting atrial fibrillation (AF).

METHODS AND RESULTS

Patients with AF included in the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) meta-analysis were the main focus of this analysis (3259 patients from 17 studies). The outcome was all-cause mortality at 3 years. Heart rate was analysed as a categorical (tertiles; T1 ≤77 b.p.m., T2 78-98 b.p.m., T3 ≥98 b.p.m.) and continuous variable. Cox proportional hazard models were used to compare the risk of all-cause death between tertiles of baseline heart rate. Patients in the highest tertile were more often female, less likely to have an ischaemic aetiology or diabetes, had a lower ejection fraction but higher blood pressure and New York Heart Association (NYHA) class. Higher heart rate was associated with higher mortality in patients with sinus rhythm (SR) but not in those in AF. In patients with heart failure and reduced ejection fraction (HF-REF) and AF, death rates per 100 patient years were lowest in the highest heart rate tertile (T1 18.9 vs. T3 15.9) but this difference was not statistically significant (P = 0.10). In patients with heart failure and preserved ejection fraction (HF-PEF), death rates per 100 patient years were highest in the highest heart rate tertile (T1 14.6 vs. T3 16.0, P = 0.014). However, after adjustment for other important prognostic variables, higher heart rate was no longer associated with higher mortality in HF-PEF (or HF-REF).

CONCLUSIONS

In this meta-analysis of patients with HF, heart rate does not have the same prognostic significance in patients in AF as it does in those in SR, irrespective of ejection fraction or treatment with beta-blocker.

Ethnic disparity in the clinical characteristics of patients with heart failure

AIMS

The characteristics of heart failure (HF) patients of different ethnic backgrounds in Israel are unknown. The purpose of the present study was to evaluate the clinical characteristics of Arab vs. Jewish patients with chronic HF.

METHODS AND RESULTS

Patients with a diagnosis of HF at a health maintenance organization in Jerusalem, Israel were evaluated. All patients were followed for cardiac-related hospitalizations and death. The study cohort included 6773 HF patients; 4991 (74%) were Jewish and 1735 (26%) were Arab. The overall prevalence of HF in the Jewish vs. Arab population was similar (women, 4.3% vs. 4.7%, respectively, P = 0.06; men, 5.3% vs. 5.2%, P = 0.61). The prevalence of HF was significantly higher in Arab subjects of younger age groups (50-70 years). Arabs developed HF on average 10 years earlier and had a significantly higher rate of diabetes and obesity. Standard of care based on prescribed medications was similar between the ethnic groups. Glucose and cholesterol levels were higher in the Arab cohort. Mortality was similar between the groups at median follow-up (576 days), with the exception of cardiovascular hospitalizations and death that were higher in Arab men.

CONCLUSIONS

Arab subjects develop HF at a much younger age compared with their Jewish counterparts and have a higher prevalence of diabetes and obesity. Standard of care and clinical outcome are comparable. Implementation of prevention programmes to reduce risk factors, particularly diabetes and obesity, may help reduce the disparity between Arabs and Jews.

Prognostic impact of hyponatraemia in patients with colorectal cancer

AIM

Hyponatraemia is a common in surgical practice, but its clinical impact in patients with colorectal cancer has not been evaluated.

METHOD

We retrospectively assessed 2944 patients who had been admitted to Chonnam National University Hwasun Hospital, Korea with a diagnosis of colorectal cancer. In order to determine the relationship between the serum sodium level and 3-year mortality, we categorized the patients as having normonatraemia (135-147 mEq/l), or mild (130-134 mEq/l), moderate (125-129 mEq/l) or severe hyponatraemia (< 125 mEq/l).

RESULTS

Hyponatraemia, defined as a serum sodium level of < 135 mEq/l, was evident in 27.6% of patients during hospitalization. Declining serum sodium levels were associated with increasing age, a higher number of comorbidities, a more advanced TNM stage and worsening biochemical parameters. In a multivariate Cox-proportional regression analysis, the mortality risk was correlated with the severity of hyponatraemia [hazard ratio (HR) 1.65, 95% CI 1.38-1.96; HR 2.24, 95% CI 1.69-2.98; HR 2.20, 95% CI 1.25-3.90, for patients with mild, moderate, and severe hyponatraemia, respectively, compared with patients with normonatraemia]. An independent association between hyponatraemia and long-term mortality was sustained among various subpopulations and patients with persistent hyponatraemia had a worse prognosis than those with hyponatraemia that resolved.

CONCLUSION

A substantial proportion of patients developed hyponatraemia during hospitalization, and the long-term mortality risk increased even in mild cases of hyponatraemia. Hyponatraemia should be considered as an important prognostic factor in colorectal cancer.

The effect of thyroid function on clinical outcome in patients with heart failure

AIMS

Thyroid dysfunction is known to effect cardiac function and is a risk factor for developing heart failure (HF). Data regarding the clinical significance of thyroid-stimulating hormone (TSH) levels alone as a predictor of outcome in patients with HF is sparse. We evaluated the significance of TSH on clinical outcome in a large cohort of patients with chronic HF.

METHODS AND RESULTS

Patients with a diagnosis of HF at a Health Maintenance Organization (n = 5599) were followed for cardiac-related hospitalizations and death. Median TSH levels were 2.2 mIU/L (interquartile range 1.4-3.5). We divided patients into quartiles based on TSH levels. Median follow-up time was 434 days and the overall mortality rate was 13.2%. Both a high and a low TSH level was associated with an increased mortality rate. Cox regression analysis after adjustment for other significant predictors demonstrated that the highest TSH quartile was associated with increased mortality compared with those with the lowest mortality [second quartile: TSH 1.4-2.2 mIU/L, hazard ratio (HR) 1.36, 95% confidence interval (CI) 1.08-1.71, P = 0.01]. TSH was also an independent predictor of death and cardiac-related hospitalization. Analysis of patients not on levothyroxine treatment (78%) demonstrated that TSH was an even stronger predictor of mortality (HR 1.54, 95% CI 1.17-2.03, P = 0.002). Additional analysis based on accepted clinical cut-offs of TSH demonstrated that increasing TSH levels above normal were independently associated with increased mortality and cardiac-related hospitalizations.

CONCLUSIONS

Increased TSH levels are associated with worse clinical outcome in patients with HF. Thyroid imbalance confers significant risk in HF and warrants attention.

Usefulness of electrocardiographic frontal QRS-T angle to predict increased morbidity and mortality in patients with chronic heart failure

The risk of death in heart failure (HF) is high. The electrocardiographic spatial QRS-T angle reflects changes in the direction of the repolarization sequence and predicts death in the general population. The frontal QRS-T angle is simple to measure but has not been evaluated in a large chronic HF cohort. We examined the significance of the frontal QRS-T angle in predicting the clinical outcome in a large cohort of patients with HF. The QRS-T angle was calculated from the frontal QRS and T axis of the baseline 12-lead surface electrocardiogram. The patients were followed for cardiac-related hospitalizations and death; 5,038 patients with HF were evaluated. The mean follow-up period was 576 days; 51% were men. Overall survival during the follow-up period was 83%. Cox regression analysis after adjustment for significant predictors, including age, gender, ischemic heart disease, hypertension, atrial fibrillation, body mass index, pulse, serum hemoglobin, sodium, estimated glomerular filtration rate, and urea levels, demonstrated that the QRS-T angle was an incremental predictor of increased mortality in both genders. For women, a QRS-T angle of ≥60° had a hazard ratio of 1.35 (95% confidence interval 1.04 to 1.75; p <0.05) and a QRS-T angle of ≥120° had a hazard ratio of 1.45 (95% confidence interval 1.10 to 1.92, p <0.01). For men, a QRS-T angle of ≥130° had a hazard ratio of 1.53 (95% confidence interval 1.14 to 2.06, p <0.01). For the whole cohort, a QRS-T angle of ≥125° gave a hazard ratio of 1.47 (95% confidence interval 1.20 to 1.80, p <0.0001). The QRS-T angle was also a predictor of increased cardiac-related hospitalizations. The QRS-T angle was a predictor in patients with reduced and preserved left ventricular function and in patients with a normal QRS interval. In conclusion, the QRS-T angle was a powerful predictor of outcome in patients with HF. We believe the QRS-T angle should be a part of the electrocardiographic evaluation of patients with HF.

Heart failure and preserved left ventricular function: long term clinical outcome

Background

Patients with heart failure (HF) have a poor prognosis. The proportion of patients with HF and preserved left ventricular function (LVF) is increasing. Long term prognosis of HF with preserved LVF may not be so benign.

Objectives

To evaluate the long term clinical outcome of patients with HF and preserved LVF and predictors of outcome.

Methods

We prospectively evaluated 309 patients hospitalized with a definite clinical diagnosis of HF. Patients were followed for a mean of 6.5 years for clinical outcome.

Results

More than a third (36%) of the patients had preserved systolic LVF based on echocardiography. The long term survival rate in this group was poor and not significantly different from patients with reduced LVF (28% vs 23% respectively, P = 0.2). The adjusted survival rate by Cox regression analysis was also not significantly different (hazard ratio 1.16, 95% confidence interval 0.87–1.55, P = 0.31). The event free survival from death or heart failure re-hospitalization was also low in both groups and not significantly different between patients with preserved vs. reduced LVF (12% vs. 10% respectively, P = 0.2). Predictors of mortality in patients with preserved LVF were age, functional capacity and serum urea levels.

Conclusions

The long term clinical outcome of patients with heart failure and preserved LVF is poor and not significantly different from patients with reduced LVF.

Vitamin D deficiency is a predictor of reduced survival in patients with heart failure; vitamin D supplementation improves outcome

AIMS

Vitamin D deficiency is a highly prevalent, global phenomenon. The prevalence in heart failure (HF) patients and its effect on outcome are less clear. We evaluated vitamin D levels and vitamin D supplementation in patients with HF and its effect on mortality.

METHODS AND RESULTS

25-Hydroxyvitamin D [25(OH)D] levels were evaluated in HF patients from a health maintenance organization (HMO), and compared them with those of the rest of the members of the HMO. Patients with HF (n = 3009) had a lower median 25(OH)D level compared with the control group (n = 46 825): 36.9 nmol/L (interquartile range 23.2-55.9) vs. 40.7 nmol/L (26.7-56.9), respectively, P < 0.00001. The percentage of patients with vitamin D deficiency [25(OH)D <25 nmol/L] was higher in patients with HF compared with the control group (28% vs. 22%, P < 0.00001). Only 8.8% of the HF patients had optimal 25(OH)D levels (≥75 nmol/L). Median clinical follow-up was 518 days. Cox regression analysis demonstrated that vitamin D deficiency was an independent predictor of increased mortality in patients with HF [hazard ratio (HR) 1.52, 95% confidence interval (CI) 1.21-1.92, P < 0.001] and in the control group (HR 1.91, 95% CI 1.48-2.46, P < 0.00001). Vitamin D supplementation was independently associated with reduced mortality in HF patients (HR 0.68, 95% CI 0.54-0.85, P < 0.0001). Parameters associated with vitamin D deficiency in HF patients were decreased previous solar radiation exposure, body mass index, diabetes, female gender, pulse, and decreased calcium and haemoglobin levels.

CONCLUSIONS

Vitamin D deficiency is highly prevalent in HF patients and is a significant predictor of reduced survival. Vitamin D supplementation was associated with improved outcome.

Does previous hypertension affect outcome in acute heart failure?

BACKGROUND

The effect of previous long-term hypertension on mortality in acute heart failure (HF), regardless of blood pressure values, has not been well studied.

METHODS

Acute Heart Failure Database (AHEAD) - Czech HF registry enrolled 4153 consecutive patients with acute HF. We excluded severe forms (cardiogenic shock, pulmonary oedema, right HF) and analysed 2421 patients with known presence or absence of previous hypertension. Demographic, clinical and laboratory profile, treatment and mortality rates were assessed and predictors of outcome were identified.

RESULTS

Patients with previous hypertension (71.5%) were older, more of female gender, with worse pre-hospitalisation NYHA class, increased incidence of co-morbidities and higher left ventricular ejection fraction (LVEF). Although in-hospital mortality was similar in both cohorts (2.6%), survival at 1, 2 and 3-year was worse in the hypertensive group (75.6%, 65.9% and 58.7% vs. 80.7%, 74.2% and 69.8%; P<0.001). Nevertheless, hypertension was not associated with mortality in multivariate analysis and stronger predictors of outcome were identified (P<0.05): new-onset acute HF [hazard ratio (HR) 0.62] and increased body mass index (HR 0.68) proved to have a protective role. Advanced age (HR 1.86), diabetes (HR 1.45), lower LVEF (HR 1.28) and admission blood pressure (HR 1.54), elevated serum creatinine (HR 1.63), hyponatremia (HR 1.77) and anaemia (HR 1.40) were associated with worse survival.

CONCLUSION

Antecedent hypertension is frequent in patients with acute HF and contributes to organ and vascular impairment. However its presence has no independent influence on short- and medium-term mortality, which is influenced by other related co-morbidities.

Myocardial ischemia in patients with diastolic dysfunction and heart failure

Coronary artery disease is present in 40-55% of patients with diastolic heart failure, and myocardial ischemia is both a cause and a precipitant of diastolic heart failure. Failure to recognize and treat acute and chronic ischemia in patients with this disorder results in rapid disease progression and poor outcomes. In diastolic heart failure patients without obstructive coronary artery disease, ischemia can be induced by other diseases that diminish perfusion gradient, cause myocardium to outgrow blood supply, or decrease diastolic filling time. In this article, we review the role of ischemia and development of fibrosis in the epidemiology, pathophysiology, and evaluation of patients with diastolic dysfunction and diastolic heart failure.

Seasonal variation in hospital admission in patients with heart failure and its effect on prognosis

BACKGROUND

A seasonal variation in hospital admissions in patients with heart failure (HF) has been described and most admissions occur during the winter season. The effect of this seasonal variation on prognosis is less clear.

OBJECTIVES

To evaluate the effect of the seasonal timing of hospital admission on clinical outcome in patients with HF.

METHODS

We prospectively enrolled 362 consecutive patients hospitalized with a definite clinical diagnosis of HF during a 2-year period. Patients were followed clinically for a period of 1 year.

RESULTS

There was a prominent seasonal variation in hospital admissions in patients with HF with peak admissions during the winter. The admission rate inversely correlated with the average monthly temperature. Admission during the summer season was a significant predictor of reduced survival (59 vs. 75%, p < 0.01). Cox regression analysis demonstrated that independent predictors of reduced survival after adjustment for other predictors were admission during the hottest 6 months or admission during the summer. In addition, increased mean environmental admission temperature was an independent predictor of reduced survival.

CONCLUSIONS

Seasonal temperature has a significant effect on the rate of hospital admission in patients with HF. Admission during warmer weather is a sign of a poor prognosis.

Clinical characteristics and predictors of in-hospital mortality in acute heart failure with preserved left ventricular ejection fraction

Acute heart failure (AHF) with preserved left ventricular ejection fraction (PLVEF) represents a significant part of AHF syndromes featuring particular characteristics. We sought to determine the clinical profile and predictors of in-hospital mortality in patients with AHF and PLVEF in the Acute Heart Failure Global Survey of Standard Treatment (ALARM-HF). This survey is an international observational study of 4,953 patients admitted for AHF in 9 countries (6 European countries, Mexico, and Australia) from October 2006 to March 2007. Patients with PLVEF were defined by an LVEF ≥ 45%. Of the total cohort, 25% of patients had PLVEF. In-hospital mortality was significantly lower in this subgroup (7% vs 11% in patients with decreased LVEF, p = 0.013). Candidate variables included demographics, baseline clinical findings, and treatment. Multivariate logistic regression analysis showed that the variables independently associated with in-hospital mortality included systolic blood pressure at admission (p <0.001), serum sodium (p = 0.041), positive troponin result (p = 0.023), serum creatinine >2 mg/dl (p = 0.042), history of peripheral vascular disease and anemia (p = 0.004 and p = 0.015, respectively), secondary (hospitalization for other reason) versus primary AHF diagnosis (p = 0.043), and previous treatment with diuretics (p = 0.023) and angiotensin-converting enzyme inhibitors (p = 0.021). In conclusion, patients with AHF and PLVEF have lower in-hospital mortality than those with decreased LVEF. Low systolic blood pressure, low serum sodium, renal dysfunction, positive markers of myocardial injury, presence of co-morbidities such as peripheral vascular disease and anemia, secondary versus primary AHF diagnosis, and absence of treatment with diuretics and angiotensin-converting enzyme inhibitors at admission may identify high-risk patients with AHF and PLVEF.

Hyponatremia as a prognostic and predictive factor in metastatic renal cell carcinoma

Background:

Low serum sodium has recently been associated with poor survival in localised renal cell carcinoma (RCC). We now show the prognostic effect of serum sodium in patients with metastatic RCC (mRCC).

Methods:

Cohort A comprised 120 consecutive patients with mRCC receiving subcutaneous, low-dose interleukin-2 and interferon-α. Hyponatremia was assessed in univariate and multivariate analyses. An independent cohort of another 120 patients with mRCC was used for validation (cohort B).

Results:

In cohort A, estimated 5-year survival was 15% and median survival was 15.1 months. Serum sodium ranged between 126 and 144 mM. Twenty-four patients (20%) had serum sodium levels below normal range (<136 mM). In multivariate analysis, significant independent risk factors for short survival were low serum sodium (P=0.014), high neutrophils (P=0.018), lactate dehydrogenase >1.5 upper normal level (P=0.002), and number of metastatic sites (+3) (P=0.003). In cohort B, serum sodium ranged between 128 and 146 mM. Seventeen patients (14%) had sodium levels below normal range. In multivariate analysis, serum sodium was validated as an independent prognostic factor (P=0.001). A significant association between lack of response and hyponatremia was observed in both cohorts (P=0.003 and P=0.02, respectively).

Conclusion:

Low serum sodium is a new, validated, independent prognostic, and predictive factor in patients with mRCC.