Echocardiographically Measured Epicardial Fat Predicts New-onset Atrial Fibrillation after Cardiac Surgery

Objective

The current study aims to investigate the role of echocardiographically measured epicardial adipose tissue (EAT) thickness in the prediction of new-onset atrial fibrillation (AF) following coronary artery bypass grafting (CABG) surgery.

Methods

One hundred and twenty-four patients scheduled to undergo isolated on-pump CABG due to coronary artery disease were enrolled to the current study. Patient characteristics, medical history and perioperative variables were prospectively collected. EAT thickness was measured using transthoracic echocardiography (TTE). Any documented episode of new-onset postoperative AF (POAF) until discharge was defined as the study endpoint. Fortyfour participants with POAF served as AF group and 80 patients without AF served as Non-AF group.

Results

Two groups were similar in terms of baseline echocardiographic and laboratory findings. In laboratory findings, the groups were similar in terms of the studied parameters, except N-terminal pro-brain natriuretic peptide (NT Pro-BNP), which was higher in AF group than in Non-AF group (P=0.035). The number of left internal mammary artery (LIMA) grafts was not different in both groups. AF group had higher cross-clamp (CC) and cardiopulmonary bypass (CPB) times than Non-AF group (P=0.01 and P<0.001). In multivariate logistic regression analysis, EAT was found an independent predictor for the development of POAF (OR 4.47, 95% CI 3.07-5.87, P=0.001).

Conclusion

We have shown that EAT thickness is associated with increased risk of AF development and can be used as a prognostic marker for this purpose.

Randomized Crossover Trial of Blood Volume Monitoring-Guided Ultrafiltration Biofeedback to Reduce Intradialytic Hypotensive Episodes with Hemodialysis

BACKGROUND AND OBJECTIVES

Intradialytic hypotension (IDH) is associated with morbidity. The effect of blood volume-guided ultrafiltration biofeedback, which automatically adjusts fluid removal rate on the basis of blood volume parameters, on the reduction of IDH was tested in a randomized crossover trial.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a 22-week, single blind, randomized crossover trial in patients receiving maintenance hemodialysis who had >30% of sessions complicated by symptomatic IDH in five centers in Calgary, Alberta, Canada. Participants underwent a 4-week run-in period to standardize dialysis prescription and dry weight on the basis of clinical examination. Those meeting inclusion criteria were randomized to best clinical practice hemodialysis (control) or best clinical practice plus blood volume-guided ultrafiltration biofeedback (intervention) for 8 weeks, followed by a 2-week washout and subsequent crossover for a second 8-week phase. The primary outcome was rate of symptomatic IDH.

RESULTS

Thirty-five participants entered, 32 were randomized, and 26 completed the study. The rate of symptomatic IDH with biofeedback was 0.10/h (95% confidence interval, 0.06 to 0.14) and 0.07/h (95% confidence interval, 0.05 to 0.10) during control (P=0.29). There were no differences in the rate or proportion of sessions with asymptomatic IDH or symptoms alone. Results remained consistent when adjusted for randomization order and study week. There were no differences between intervention and control in the last study week in interdialytic weight gain (difference [SD], -0.02 [0.8] kg), brain natriuretic peptide (1460 [19,052] ng/L), cardiac troponins (3 [86] ng/L), extracellular water-to-intracellular water ratio (0.05 [0.33]), ultrafiltration rate (1.1 [7.0] ml/kg per hour), and dialysis recovery time (0.43 [19.25] hours).

CONCLUSION

The use of blood volume monitoring-guided ultrafiltration biofeedback in patients prone to IDH did not reduce the rate of symptomatic IDH events.

NT-proBNP and Echocardiographic Parameters for Prediction of Cardiovascular Outcomes in Patients with CKD Stages G2-G4

BACKGROUND AND OBJECTIVES

Natriuretic peptides and echocardiographic parameters both predict cardiovascular events in patients with CKD. However, it is unknown whether simultaneous assessment of amino-terminal probrain natriuretic peptide (NT-proBNP) and echocardiographic parameters provides complementary or redundant predictive information; in the latter case, one of these two might be dispensable. We aimed to analyze the implications of using NT-proBNP alone, echocardiographic parameters alone, or a combination of both for prediction of adverse cardiovascular outcome.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Within the longitudinal Cardiovascular and Renal Outcome in CKD 2-4 Patients-The Fourth Homburg Evaluation Study, we prospectively studied 496 patients with CKD stages G2-G4, in whom we measured NT-proBNP. Left ventricular mass index, left atrial volume index, diastolic left ventricular function, and systolic left ventricular function were assessed echocardiographically. During 4.5±2.0 years of follow-up, the occurrence of (1) decompensated heart failure or all-cause mortality and (2) atherosclerotic events or all-cause mortality was recorded. We assessed the association of NT-proBNP and echocardiographic parameters with outcome (using Cox models) and evaluated the increased discriminative value associated with the addition of echocardiographic parameters and NT-proBNP (using integrated discrimination improvement and net reclassification improvement).

RESULTS

During follow-up, 104 patients suffered decompensated heart failure or all-cause mortality, and 127 patents had atherosclerotic events or all-cause mortality. In univariable analyses, NT-proBNP and echocardiographic parameters predicted cardiovascular events. NT-proBNP remained an independent predictor for both end points in multivariate analysis, whereas left ventricular mass index, left atrial volume index, and diastolic left ventricular function did not. The addition of NT-proBNP on top of clinical and various echocardiographic variables was associated with improvements in reclassification for decompensated heart failure or all-cause mortality (integrated discrimination improvement =6.5%-8.3%; net reclassification improvement =23.1%-27.0%; all P≤0.03). Adding echocardiographic variables on top of clinical variables and NT-proBNP was not associated with significant net reclassification improvement (all P>0.05).

CONCLUSIONS

Our data confirm NT-proBNP is an independent predictor of adverse outcomes in patients with CKD. The additional use of echocardiography for improvement of risk stratification is not supported by our results.

Role of Soluble ST2 as a Prognostic Marker in Patients with Acute Heart Failure and Renal Insufficiency

This study sought to assess the relationship between serum concentrations of the soluble ST2 (sST2) and B-type natriuretic peptide (BNP) and investigate the role of sST2 as a prognosticator in patients hospitalized with acute heart failure (HF) and renal insufficiency. sST2 was measured at admission and discharge in 66 patients hospitalized with acute decompensated HF and renal insufficiency (estimated glomerular filtration rate [eGFR] < 90 mL/min/1.73 m(2)) using a high sensitivity immunoassay. BNP was sampled at the same time and compared to sST2. Demographical, biochemical, and echocardiographic data were also obtained during hospitalization.There were positive correlations between sST2 and BNP levels at admission (r = 0.330, P = 0.007) and at discharge (r = 0.320, P = 0.009) in overall patients. However, there was no correlation between them at each timepoint in patients with severe renal insufficiency (eGFR < 30 mL/min/1.73 m(2), n = 17). sST2 level was not changed with the degree of renal function, even though BNP level was much higher in patients with severe renal insufficiency. During 3 month follow-up, 9 (13.6%) died and 16 (24.2%) were readmitted due to HF aggravation.On multivariate analysis, sST2 at discharge was independently associated with death or HF readmission during 3 months after discharge (hazard ratio, 1.038; 95% confidence interval, 1.011-1.066, P = 0.006). In conclusion, sST2 is not affected by renal function compared with BNP in acute HF patients. The measurement of predischarge sST2 can be helpful in predicting short-term outcomes in acute decompensated HF patients with renal insufficiency.

One-year prognosis and the role of brain natriuretic peptide levels in patients with chronic cor pulmonale

Data on the clinical outcomes and role of brain natriuretic peptide (BNP) levels in patients with chronic cor pulmonale are limited. A total of 69 patients with chronic cor pulmonale, admitted for dyspnea (January 2007 to September 2011) to three university hospitals, were retrospectively reviewed. All of the patients had right ventricular (RV) dysfunction on echocardiography. The median age was 70.0 yr, and chronic obstructive pulmonary disease (40.6%) and tuberculosis-destroyed lung (TDL, 27.5%) were the leading causes of chronic cor pulmonale. At the 1-yr follow-up, the mortality rate was 15.9%, and the readmission rate was 53.7%; patients with TDL had higher mortality (31.6% vs. 10.0%; P=0.059) and readmission rates (78.9% vs. 43.8%; P=0.009) than those with non-TDL diseases. The area under the receiver operating characteristic curve for admission BNP levels to predict readmission was 0.788 (95% confidence interval [CI], 0.673-0.904), and the sensitivity and specificity of the cut-off value were 80.6% and 77.4%, respectively. In multivariate analysis, high admission BNP levels were a significant risk factor for subsequent readmission (hazard ratio, 1.049; 95% CI, 1.005-1.094). Additionally, admission BNP levels were well correlated with cardiac troponin I (r=0.558), and delta BNP also correlated with delta RV systolic pressure (n=25; r=0.562). In conclusion, among hospitalized patients with chronic cor pulmonale, admission high BNP levels are a significant risk factor for subsequent readmission. Therefore, more intensive monitoring and treatment are needed in patients with higher BNP levels.

Predictors of cardiogenic and non-cardiogenic causes in cases with bilateral chest infiltrates

Background

Differentiating cardiogenic pulmonary edema from other bilateral lung diseases such as pneumonia is frequently difficult. We conducted a retrospective study to identify predictors for cardiogenic pulmonary edema and non-cardiogenic causes of bilateral lung infiltrates in chest radiographs.

Methods

The study included patients who had newly developed bilateral lung infiltrates in chest radiographs and patients who underwent echocardiography. Cases were divided into two groups based on the echocardiographic findings: the cardiogenic pulmonary edema group and the non-cardiogenic group. Clinical characteristics and basic laboratory findings were analyzed to identify predictors for differential diagnosis between cardiogenic and non-cardiogenic causes of bilateral chest infiltrates.

Results

We analyzed 110 subjects. Predictors of cardiogenic pulmonary edema were higher brain natriuretic peptide (BNP) levels, lower C-reactive protein (CRP) levels on the day of the event (<7 mg/dL), age over 60 years, history of heart disease, and absence of fever and sputum. CRP on the day of the event was an independent factor to differentiate cardiogenic and non-cardiogenic causes of newly developed bilateral chest infiltrates. Also, the validity was comparable to BNP.

Conclusion

Clinical symptoms (sputum and fever), medical history (dyslipidemia and heart disease), and laboratory findings (BNP and CRP) could be helpful in the differential diagnosis of patients with acute bilateral lung infiltrates in chest radiographs.