Donna R. Zwas

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

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.

The significance of serum urea and renal function in patients with heart failure.

Renal function and urea are frequently abnormal in patients with heart failure (HF) and are predictive of increased mortality. The relative importance of each parameter is less clear. We prospectively compared the predictive value of renal function and serum urea on clinical outcome in patients with HF. Patients hospitalized with definite clinical diagnosis of HF (n = 355) were followed for short-term (1 yr) and long-term (mean, 6.5 yr) survival and HF rehospitalization. Increasing tertiles of discharge estimated glomerular filtration rate (eGFR) were an independent predictor of increased long-term survival (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.47-0.91; p = 0.01) but not short-term survival. Admission and discharge serum urea and blood urea nitrogen (BUN)/creatinine ratio were predictors of reduced short- and long-term survival on multivariate Cox regression analysis. Increasing tertiles of discharge urea were a predictor of reduced 1-year survival (HR, 2.13; 95% CI, 1.21-3.73; p = 0.009) and long-term survival (HR, 1.93; 95% CI, 1.37-2.71; p < 0.0001). Multivariate analysis including discharge eGFR and serum urea demonstrated that only serum urea remained a significant predictor of long-term survival; however, eGFR and BUN/creatinine ratio were both independently predictive of survival. Urea was more discriminative than eGFR in predicting long-term survival by area under the receiver operating characteristic curve (0.803 vs. 0.787; p = 0.01). Increasing tertiles of discharge serum urea and BUN/creatinine were independent predictors of HF rehospitalization and combined death and HF rehospitalization. This study suggests that serum urea is a more powerful predictor of survival than eGFR in patients with HF. This may be due to ureas relation to key biological parameters including renal, hemodynamic, and neurohormonal parameters pertaining to the overall clinical status of the patient with chronic HF. Abbreviations: ADHF = acute decompensated heart failure, AUC = area under the curve, BUN = blood urea nitrogen, CI = confidence interval, eGFR = estimated glomerular filtration rate, HF = heart failure, HR = hazard ratio, MDRD = Modification of Diet in Renal Disease, ROC = receiver operating characteristic.

Clinical Outcome of Patients with Heart Failure and Preserved Left Ventricular Function

BACKGROUND Patients with heart failure have a poor prognosis. However, it has been presumed that patients with heart failure and preserved left ventricular function (LVF) may have a more benign prognosis. OBJECTIVES We evaluated the clinical outcome of patients with heart failure and preserved LVF compared with patients with reduced function and the factors affecting prognosis. METHODS We prospectively evaluated 289 consecutive patients hospitalized with a definite clinical diagnosis of heart failure based on typical symptoms and signs. They were divided into 2 subsets based on echocardiographic LVF. Patients were followed clinically for a period of 1 year. RESULTS Echocardiography showed that more than one third (36%) of the patients had preserved systolic LVF. These patients were more likely to be older and female and have less ischemic heart disease. The survival at 1 year in this group was poor and not significantly different from patients with reduced LVF (75% vs 71%, respectively). The adjusted survival by Cox regression analysis was not significantly different (P=.25). However, patients with preserved LVF had fewer rehospitalizations for heart failure (25% vs 35%, P<.05). Predictors of mortality in the whole group by multivariate analysis were age, diabetes, chronic renal failure, atrial fibrillation, residence in a nursing home, and serum sodium < or = 135 mEq/L. CONCLUSION The prognosis of patients with clinical heart failure with or without preserved LVF is poor. Better treatment modalities are needed in both subsets.

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

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.

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.

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.

Temporal changes in electrocardiographic frontal QRS-T angle and survival in patients with heart failure

Background Heart failure (HF) is associated with considerable mortality. The electrocardiographic frontal QRS-T angle is a simple parameter to measure, reflects changes in the direction of the repolarization sequence and predicts outcome in patients with HF. Data regarding temporal changes in the frontal QRS-T angle in patients with HF and its impact on outcome is limited. Aim To evaluate temporal changes in the frontal QRS-T angle and its effect on survival in patients with HF. Methods Baseline and follow-up QRS-T angle were calculated from the frontal QRS and T axis of the 12-lead surface electrocardiogram. Patients were followed for survival. Results 2,929 HF patients were evaluated. Median interval between baseline ECG and follow-up ECG was 895 days, median follow-up time was 1526 days. Overall, the QRS-T angle tended to be stable, with minor changes in the angle over time. The median QRS-T angle change was +3° (IQR -19° to +30°). Overall survival during follow-up was 60%. Cox regression analysis after adjustment for significant predictors demonstrated that the QRS-T angle was an incremental predictor of increased mortality. A widening of the QRS-T angle during follow-up was independently associated with an increase in mortality, evident with an increase of the QRS-T angle difference above 0° (P<0.0001 for the adjusted model). Conclusion QRS-T angle is relatively stable in patients with HF and is a powerful predictor of outcome. Widening of the QRS-T angle has predictive value and is an ominous sign.

Electrocardiographic Predictors of Morbidity and Mortality in Patients With Acute Myocarditis: The Importance of QRS-T Angle

BACKGROUND Acute myocarditis carries a variable prognosis. We evaluated the morbidity and mortality rates in patients with acute myocarditis and admission electrocardiographic predictors of outcome. METHODS AND RESULTS Patients admitted to a tertiary hospital with a clinical diagnosis of acute myocarditis were evaluated; 193 patients were included. Median follow-up was 5.7 years, 82% were male, and overal median age was 30 years (range 21-39). The most common clinical presentations were chest pain (77%) and fever (53%). The 30-day survival rate was 98.9%. Overall survival during follow-up was 94.3%. The most common abnormalities observed on electrocardiography were T-wave changes (36%) and ST-segment changes (32%). Less frequent changes included abnormal T-wave axis (>105° or < -15°; 16%), abnormal QRS axis (12%), QTc >460 ms (11%), and QRS interval ≥120 ms (5%). Wide QRS-T angle (≥100°) was demonstrated in 13% of the patients and was associated with an increased mortality rate compared with patients with a narrow QRS-T angle (20% vs 4%; P = .007). The rate of heart failure among patients with a wide QRS-T angle was significantly higher (36% vs 10%; P = .001). Cox regression analysis demonstrated that a wide QRS-T angle (≥100°) was a significant independent predictor of heart failure (hazard ratio [HR] 3.20, 95% confidence interval [CI] 1.35-7.59; P < .01) and of the combined end point of death or heart failure (HR 2.56, 95% CI 1.14-5.75; P < .05). CONCLUSIONS QRS-T angle is a predictor of increased morbidity and mortality in acute myocarditis.