Plasma natriuretic peptide levels reflect changes in heart failure symptoms, left ventricular size and function after surgical mitral valve repair

Normalization of N-Terminal Pro-B-Type Natriuretic Peptide After Cardiac Surgery Among Children With Tetralogy of Fallot

The aim of this study was to temporally measure N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels over a period of 18 months after corrective surgery among children with tetralogy of Fallot (TOF) and to explore how commonly used pharmaceuticals (i.e., spironolactone and digoxin) might affect the normalization pattern. This retrospective study included 136 children with a median age of 7 months who underwent cardiac surgery for TOF. NT-proBNP level was measured at 1, 3, 6, 12, and 18 months after the surgery. Normalization of NT-proBNP was defined as an NT-proBNP level ≤250 pg/ml. The commonly used pharmaceuticals spironolactone and digoxin after discharge were collected. The normalization pattern, normalization time, and potential influence of the pharmaceuticals were determined. The rate of normalization was 24.2% (95% confidence interval [CI] 8.58% to 68.4%) per 100 person-days. Kaplan-Meier survival analysis showed a median normalization time of 517 (95% CI 429.6 to 604.3) days. The children whose NT-proBNP level did not normalize had a significantly higher readmission rate than those whose NT-proBNP level normalized (19.0% vs 2.8%, p = 0.018). Multivariable logistic regression models confirmed that the regular users of spironolactone, alone (odds ratio = 1.45, 95% CI 1.15 to 1.83) or in combination with digoxin (odds ratio = 1.28, 95% CI 1.03 to 1.58), had markedly faster recovery trajectories for measures of NT-proBNP than the irregular users of both. In conclusion, NT-proBNP normalization after cardiac surgery for TOF is a lengthy process, and irregular use of spironolactone could lead to failure in recovery and hospital readmission.

Natriuretic peptides in the evaluation and management of degenerative mitral regurgitation: a systematic review

Progression of degenerative mitral regurgitation (MR) leads to irreversible cardiac damage. Therefore, longitudinal follow up to determine the optimal timing of surgery is critical. Current data indicates that in addition to the standard of care-assessing for symptoms and signs of left ventricular (LV) decompensation with routine echocardiography-serial measurement of natriuretic peptides offers a quantitative means to identify patients who may benefit from closer supervision, if not surgery. Natriuretic peptide levels, and specifically changes from baseline, identify both symptomatic patients and others likely to develop cardiac dysfunction. Moreover, because natriuretic peptides are complimentary to the echocardiographic assessment of MR. Finally, changes in natriuretic peptides levels are predictive of pre- and post-operative outcomes. In short, natriuretic peptides add objectivity to the management of degenerative MR, which may aid practitioners in identifying patients who could benefit from intensive monitoring, stress testing, and perhaps mitral surgery.

Dynamics of the liver stiffness value using transient elastography during the perioperative period in patients with valvular heart disease

Background/Aims

Liver congestion due to heart failure in patients with valvular heart disease (VHD) can result in an overestimate of the liver stiffness (LS) as assessed by transient elastography (TE). This prospective pilot study investigated the dynamics of LS during the perioperative valve operation period.

Methods

Thirty-two patients who underwent a valve operation (case) and 12 who underwent a varicose vein operation (control) were prospectively enrolled. LS and cardiologic parameters at three time points [baseline, post-operative day (POD)7, and POD90] were collected.

Results

LS at three time points were consistently higher in the case group than those in the control group, although all participants did not show evidence of underlying chronic liver disease (all P<0.05). In the case group, LS at POD7 increased slightly from the LS at baseline (median 7.9→8.4 kPa, P = 0.816), whereas LS at POD90 decreased significantly from the LS at POD7 (median 8.4→6.0 kPa; P = 0.026). LS was significantly correlated with N-terminal-pro brain natriuretic peptide (NT-proBNP) (ρ = 0.412), left ventricular ejection fraction (ρ = −0.494), and central venous pressure during the operation (ρ = 0.555) at baseline (all P<0.05). LS was significantly correlated with NT-proBNP (ρ = 0.526) and right ventricular pressure (ρ = 0.572) at POD7, whereas LS was significantly correlated with NT-proBNP (ρ = 0.590) at POD90 (all P<0.05).

Conclusions

LS can be overestimated in patients with VHD due to hepatic congestion. However, LS can be dynamically reversed during the perioperative period reflecting the restoration of cardiac function after a successful operation.

NT-pro-brain natriuretic peptide levels after valve replacement

Elevated plasma N-terminal pro-brain natriuretic peptide levels have been demonstrated in patients with chronic valvular disease. To assess whether changes in N-terminal pro-brain natriuretic peptide levels after mitral, aortic, and double-valve replacement reflect changes in heart failure symptoms, a prospective observational nonrandomized study was undertaken in 24 consecutive patients (mean age, 55.3 ± 16.2 years; 58% male) undergoing mitral and/or aortic valve replacement. Mitral valve replacement was carried out in 12 patients, aortic valve replacement in 8, and combined mitral and aortic valve replacement in 4. N-terminal pro-brain natriuretic peptide measurements, echocardiography, and functional class assessment were performed before and 6 months after surgery. A decrease in N-terminal pro-brain natriuretic peptide at 6 months postoperatively was significantly associated with decreased left atrial dimension, left ventricular end-diastolic and end-systolic dimensions, increased ejection fraction, and improvement in functional class. Thus we can hypothesize that measurement of N-terminal pro-brain natriuretic peptide might allow early detection of any clinical deterioration as well as assessment of the long-term outcome in valve replacement patients.

[Echocardiographic predictors of exercise capacity in patients with heart failure and systolic dysfunction: role of mitral regurgitation]

INTRODUCTION AND OBJECTIVES

Patients with heart failure and similar left ventricular systolic dysfunction have differing exercise capacity. The aim of this study was to identify echocardiographic predictors of exercise capacity in patients with heart failure and systolic dysfunction.

METHODS

We included 150 patients with class II (70%) or III (30%) heart failure with left ventricular ejection fraction below 40%. Six-minute walking test and cardiac color Doppler-echo, including tissue Doppler of mitral and tricuspid rings, were performed. Moderate and severe mitral regurgitation were considered as significant. Two groups were divided according to the median walking distance (290 m): Group 1, <290 m and Group 2, ≥290 m.

RESULTS

Mitral regurgitation was detected in 112 patients (75%), which was significant in 40 (27%). Group 1 showed more significant mitral regurgitation (35 vs 18%), increased left atrium area (27±1 vs 24±1cm(2)), mitral E amplitude (88±5 vs 72±3cm/s) and systolic pulmonary pressure (37±1 vs 32±1mmHg, all P<.05). By logistic regression analysis, only the presence of significant mitral regurgitation was independently associated with less walked distance (odds ratio: 3.44 95% confidence interval 1.02-11.66, P<.05). By multiple linear regression, the only independent predictor of walked distance was left atrium area (r=0.25, beta coefficient: -6.52±2, P<.01).

CONCLUSIONS

In patients with class II-III heart failure and left ventricular systolic dysfunction, the main echocardiographic predictors of exercise capacity are related to the presence of significant mitral regurgitation.

Is serial determination of inspiratory muscle strength a useful prognostic marker in chronic heart failure?

BACKGROUND

Little data exists on the prognostic role of inspiratory muscle strength (PImax) in chronic heart failure (CHF). Training studies, however, frequently use it as a therapeutic target and surrogate marker for prognosis. The prognostic value of changes of PImax that allow this extrapolation is unknown.

DESIGN

Patients with stable CHF were prospectively included and 1-year and all-time event rates recorded for endpoint analysis.

METHODS

In 158 patients (85% men; New York Heart Association functional class: 2.4+/-0.6), PImax was measured along with clinical evaluations at two visits, the initial visit and the second visit, 6.4+/-1.4 months apart. The mean follow-up was 59+/-34 months.

RESULTS

Overall, 59 patients (37%) reached the primary endpoint of death or hospitalization (endpoint positive), and overall mortality rate (secondary endpoint) was 26% (42 patients). PImax did not differ between endpoint-negative and endpoint-positive patients, both at the initial and at the second visit (8.3+/-5.6 vs. 7.3+/-3.4 kPa and 8.8+/-6.0 vs. 7.9+/-3.6 kPa, respectively; P=NS), and both groups showed increased PImax (0.6+/-2.6 vs. 0.6+/-2.8 kPa; P=NS). Cox analyses found neither the absolute nor the relative change of PImax to be significant predictors for the primary and secondary endpoints (P=NS for both), both for the 1-year and for the all-time event rates. Endpoint rates did not differ between patients showing increasing or decreasing PImax (P=NS; relative risk (RR): 0.77; 95% confidence interval: 0.47-1.27).

CONCLUSION

Trials focusing on inspiratory muscle function should use the actual levels of PImax as a surrogate marker to represent prognostic information, rather than relative or absolute changes. This is the first study to investigate the prognostic information of the changes of PImax over time, regarding both short-term and long-term morbidity and mortality in patients with stable CHF.

Biomarkers in heart failure management

PURPOSE OF REVIEW

Recent literature on the role of biomarkers in heart failure is reviewed, focusing on B-type natriuretic peptide.

RECENT FINDINGS

Knowledge of the processes which increase ventricular stress, thus increasing B-type natriuretic peptide, is key to appropriate utilization and interpretation of B-type natriuretic peptide levels. B-type natriuretic peptide is a useful adjunct to confirm or rule out heart failure. B-type natriuretic peptide is a robust prognostic indicator in all stages of heart failure, with prognostic significance in patients undergoing cardiac and noncardiac surgery, and in those with acute coronary syndromes. Serial B-type natriuretic peptide testing predicts outcomes in hospitalized patients with heart failure. The role of B-type natriuretic peptide in screening high-risk populations is promising, but its use in unselected populations is unclear. There is increasing evidence that the use of B-type natriuretic peptide to guide heart failure management is associated with improved clinical outcomes and reduced health costs.

SUMMARY

Biomarkers play an important role in heart failure, but there remain unanswered questions regarding optimization of their use. They should be used as an adjunct to, not replacement for, clinical assessment. Currently available B-type natriuretic peptide assays have limitations relating to clinical variability and assay specificity. Other neurohormonal, inflammatory and metabolic markers may add complementary information to that provided by currently available B-type natriuretic peptide assays.

The relationship between the level of plasma B-type natriuretic peptide and mitral stenosis

B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are both secreted primarily from the ventricle myocardium in response to the increase in volume and pressure. We aimed to investigate the relationship between the severity of mitral stenosis (MS) and the level of plasma BNP. A total of 56 patients (50 female, 6 male) were included in the study. Mitral stenosis and its related parameters were evaluated by echocardiographic methods. Patients were divided into three groups as with mild, moderate and severe MS according to their planimetric valvular area. Plasma BNP levels were measured using "Triage-B-type natriuretic peptide test" method (Biosite Diagnostics, San Diego). The relationship of BNP with mitral stenosis and other echocardiographic parameters were studied. The comparison of the 3 groups with one another revealed that the BNP level in the group with moderate MS was higher than that in the group with mild MS, however it was statistically insignificant (74.9 +/- 49.7 versus 49.9 +/- 40.5 pg/ml, p > 0.05). BNP level in the group with severe MS was significantly higher than that in the mild MS (144.3 +/- 83.9 versus 49.9 +/- 40.5 pg/ml, p < 0.001) and that in the moderate MS group (144.3 +/- 83.9 versus. 74.9 +/- 49.7 pg/ml, p < 0.05). When patients were taken together, as the area of the mitral valve decreased, the level of BNP underwent a corresponding increase (r:-0.48, p < 0.001). We have ascertained that the level of plasma BNP and the degree of MS are significantly correlated, and as MS becomes more serious, the plasma BNP level rises.

Effect of beta-blocker therapy on left atrial function in patients with heart failure: comparison of metoprolol succinate with carvedilol

OBJECTIVE

We aimed to compare the effects of carvedilol and metoprolol succinate on left atrial (LA) function in patients with chronic heart failure.

METHODS

Thirty three patients (6 females, 27 males) who had not received beta blocker treatment previously and whose left ventricular ejection fraction was below 40% were included in this study. LA volumes were measured echocardiographically just before the time of mitral valve opening (V (max)), onset of atrial systole (p-wave at the electrocardiography = V (p)) and mitral valve closure (V (min)) according to the biplane area length method at baseline and in the 3rd month after the administration of beta blockers. NT-proBNP level was measured at the beginning and in the third month of beta blocker treatment. The first group was given carvedilol 6.25 mg/day, the second group was given 12.5 mg/day metoprolol succinate and it was increased to the tolerable maximal dose.

RESULTS

LA diameter and LA V (max), V (p), V (min) decreased significantly both in carvedilol group and metoprolol group after beta blocker theraphy (P < 0.01, : P < 0.01, : P < 0.05, : P < 0.05: for metoprolol, P < 0.001, P < 0.01, P < 0.01, P < 0.01 for carvedilol). But it was increased in conduit volume (P < 0.05 for two groups). LA-passive emptying fraction, LA-active emptying fraction and reservoir fraction were no significant differences both in carvedilol group and metoprolol group after beta blocker theraphy. NT-proBNP levels were found to decrease significantly in both groups after beta blocker treatment (P < 0.001).:

CONCLUSION

Our findings indicate that beta blocker treatment leads to a decrease in LA diameters and volumes, and metoprolol succinate and carvedilol had similar effects on this decrease.