Single-chamber ventricular pacing increases markers of left ventricular dysfunction compared with dual-chamber pacing.

AIMS: Large randomized trials comparing DDD with VVI pacing have shown no differences in mortality, but conflicting evidence exists in regard to heart failure endpoints. Here we evaluated the effect of pacing mode on serum levels of brain natriuretic peptide (BNP) and amino-terminal-proBNP (NT-proBNP). Methods Forty-one patients (age 73 +/- 10 years) with dual-chamber pacemakers were included in a prospective, single-blind, randomized crossover study evaluating the impact of DDD(R)/VDD versus VVI(R) mode on objective and functional parameters. Data were collected after a 2-week run-in phase and after 2 weeks each of VVI(R) and DDD(R)/VDD pacing or vice versa. Results BNP and NT-proBNP levels during DDD(R)/VDD stimulation (151 +/- 131 and 547 +/- 598 pg/mL) showed no change compared with baseline (154 +/- 130 and 565 +/- 555 pg/mL), but a significant 2.4-fold increase was observed during VVI(R) mode [360 +/- 221 and 1298 +/- 1032 pg/mL; P < 0.001 compared with DDD(R)/VDD]. The assessment of functional class, the presence of pacemaker syndrome [49% in VVI(R) mode] and the patients' preferred pacing mode showed significant differences in favour of DDD(R)/VDD pacing. CONCLUSION: Patients can differentiate between DDD(R)/VDD and VVI(R) pacing, and prefer the former. Compared with DDD(R)/VDD pacing, VVI(R) stimulation induces a two- to three-fold increase in serum BNP and NT-proBNP levels.     

Brain natriuretic peptide as a marker of cardiac involvement in hypertension.

Hypertensive patients with heart abnormalities have increased risk of cardiovascular events. Brain natriuretic peptide is a natriuretic peptide mainly of ventricular origin produced in response to pressure and stretch. We hypothesise that brain natriuretic peptide could be a useful marker of cardiac remodelling in hypertensive patients. We studied 36 consecutive community mild-to-moderate hypertensive patients and 11 well-matched normotensive controls with respect to clinical characteristics, brain natriuretic peptide, creatinine and echocardiography parameters (M-mode, 2-D arid transmitral pulsed Doppler). Brain natriuretic peptide levels were significantly higher in hypertensive patients than in controls [36.54 (IQR: 38.61) vs. 10.30 (IQR: 13.20) pg ml(-1), p<0.0001] and it was correlated with left ventricular mass index. Hypertensive patients with impairment of diastolic filling had significantly higher brain natriuretic peptide concentrations than patients with no abnormalities on echocardiography [61.16 (45.38) vs. 31.27 (18.10) pg ml(-1), p=0.001]. Multivariate analysis showed that only diastolic dysfunction and left ventricular mass index were significantly and independently related with brain natriuretic peptide concentrations in this population. In conclusion, impairment of diastolic function and left ventricular mass index are related to brain natriuretic peptide levels, thus giving the insight that this peptide can be a marker of ventricular remodelling in hypertensive patients.     

Brain natriuretic peptide and left ventricular dysfunction in Chagas' disease

Left ventricular dysfunction in Chagas' disease is common but can be difficult to detect. We investigated whether measurement of plasma brain natriuretic peptide (BNP) could identify patients with left ventricular dysfunction who need further investigation or treatment. Among patients with an abnormal electrocardiogram or chest radiograph, a BNP concentration of 60.7 pmol/L or higher has a sensitivity and positive predictive value of 80%, and specificity and negative predictive value of 97%. Measurement of plasma BNP concentration could be a useful method to screen patients with Chagas' disease.     

Brain natriuretic peptide predicts chronic atrial fibrillation after ventricular pacing in patients with sick sinus syndrome

Chronic atrial fibrillation (AF) is one of the main complications of sick sinus syndrome (SSS). As previously reported, plasma brain natriuretic peptide (BNP), reflects hemodynamic changes in different pacing modes, as does plasma atrial natriuretic peptide (ANP), so the present study investigated whether plasma BNP or ANP can predict chronic AF after single-chamber ventricular (VVI) pacemaker implantation in patients with SSS. Plasma ANP and BNP levels were measured before and 1-3 months after implantation in 99 SSS patients. Long-term follow-up was conducted with chronic AF as an endpoint. Chronic AF occurred in 19 patients during a mean follow-up of 5.1 years. Plasma ANP and BNP were significantly higher in the patients who developed chronic AF after implantation than in those who did not, despite similar ANP and BNP levels between the 2 groups before implantation. Post-implant high BNP and a history of paroxysmal AF were independent predictors of chronic AF by a multivariate Cox proportional hazards analysis. Plasma BNP can predict the development of chronic AF after VVI pacemaker implantation in patients with SSS because increased levels may reflect latent hemodynamic abnormalities, which may contribute to the development of AF after VVI pacemaker implantation.     

Brain natriuretic peptide based strategy to detect left ventricular dysfunction in Chagas disease: a comparison with the conventional approach

BACKGROUND: Left ventricular dysfunction (LVd) is the main predictor of mortality in Chagas disease (ChD). AIMS: To compare the diagnostic performance of the conventional approach (ECG and chest X-ray) in the recognition of LVd in ChD, with a new strategy, in which BNP is measured in patients with an abnormal ECG. METHODS: Consecutive ChD patients recruited at an Outpatient Reference Center in Belo Horizonte, Brazil, without other systemic diseases, in 1998-99 (sample 1, n = 165) and in 2001-02 (sample 2, n = 62) underwent ECG, chest X-ray, BNP measurement and echocardiography. RESULTS: The prevalence of LVd (ejection fraction 相似文献   

Heart failure in patients with sick sinus syndrome treated with single lead atrial or dual-chamber pacing: no association with pacing mode or right ventricular pacing site

AIMS: Previous studies indicate that ventricular pacing may precipitate heart failure (HF). We investigated occurrence of HF during long-term follow-up among patients with sick sinus syndrome (SSS) randomized to AAIR or DDDR pacing. Furthermore, we investigated effects of percentage of ventricular pacing (%VP) and pacing site in the ventricle. METHODS AND RESULTS: We analysed data from 1415 patients randomized to AAIR (n = 707) or DDDR pacing (n = 708). Ventricular pacing leads were recorded as located in either an apical or a non-apical position. The %VP and HF hospitalizations were recorded during follow-up. Patients were classified with new HF, if in New York Heart Association (NYHA) functional class IV or if presence of ≥2 of: oedema; dyspnoea; NYHA functional class III. Mean follow-up was 5.4 ± 2.4 years. Heart failure hospitalizations did not differ between groups. In the AAIR group, 170 of the 707 (26%) patients developed HF vs. 169 of the 708 (26%) patients in the DDDR group, hazard rate ratio (HR) 1.00, 95% confidence interval (CI) 0.79-1.22, P = 0.87. In DDDR patients, 146 of the 512 patients (29%) with ventricular leads in an apical position developed HF vs. 28 of the 161 patients (17%) with the leads in a non-apical position, HR 0.67, CI 0.45-1.00, P = 0.05. After adjustments this difference was non-significant. The incidence of HF was not associated with %VP (P = 0.57). CONCLUSION: In patients with SSS, HF was not associated with pacing mode, %VP, or ventricular lead localization. This suggests that DDDR pacing is safe in patients with SSS without precipitating HF.     

Brain natriuretic peptide levels and cardiac functional capacity in patients with dyspnea and isolated diastolic dysfunction

Diastolic heart failure affects approximately 40%-50% of patients presenting with signs and symptoms of heart failure. The aim of this study was to investigate the relationship between brain natriuretic peptide (BNP) levels and functional capacity in patients admitted with dyspnea and diagnosed with isolated diastolic dysfunction. Fifty-four patients (mean age, 57.4 +/- 8.5 years) with class-2 dyspnea with isolated diastolic dysfunction were enrolled. Serum levels of BNP were measured, and peak oxygen consumption (peak VO(2)), anaerobic threshold (AT), and metabolic equivalent (MET) values were determined with a cardiopulmonary exercise test (CPET). There was a negative correlation between BNP levels and exercise duration (P < 0.05, r = -0.304), AT (P < 0.05, r = -0.380), and number of MET (P < 0.05, r = -0.322) determined by CPET. When patients were divided into 2 groups according to BNP levels; BNP < or = 50 pg/mL (n = 40) versus BNP > 50 pg/mL (n = 14) and analyzed, those with BNP levels > 50 pg/mL had lower peak VO(2) (P = 0.05) and anaerobic threshold (P = 0.01) compared with patients with BNP < or = 50 pg/mL. The results suggest that BNP levels provide an indication about the functional capacity determined by CPET in patients admitted with dyspnea and isolated diastolic dysfunction.     

Brain natriuretic peptide: a potential marker for mortality in septic shock.

Brain natriuretic peptide (BNP) is a diagnostic marker for left ventricular dysfunction. Sepsis and septic shock are increasing in incidence and mortality. Myocardial dysfunction frequently accompanies severe sepsis and septic shock. Although previously described as a preterminal event, ventricular dysfunction with reduced ejection fraction and biventricular dilatation is present in most patients with severe sepsis and septic shock. In survivors, this depression in cardiac function is reversible over the course of seven to ten days. Even though some prognostic factors have been identified in patients with sepsis-induced myocardial dysfunction, their measurement often includes costly and cumbersome techniques. Thus, there is a need for an inexpensive, simple, rapid and readily available marker to predict mortality in septic shock. At present, a relationship between BNP with myocardial dysfunction in septic shock has not been evaluated. However, growing evidence supports the hypothesis that BNP could be an early predictor of mortality in septic shock. If proven, the hypothesis would have important clinical and public health implications.     

Evaluation of brain natriuretic peptide as marker of left ventricular dysfunction and hypertrophy in the population

OBJECTIVE: To evaluate brain natriuretic peptide (BNP) as marker of left ventricular (LV) dysfunction and hypertrophy in a population-based sample of 610 middle-aged subjects (50-67 years) who were further characterized with respect to hemodynamic and anthropometric parameters and by echocardiography. RESULTS: Left ventricular (LV) systolic function, LV mass-index, age, gender, heart rate, and medication with beta adrenergic receptor blockers were significant and independently correlated with BNP (multivariate analysis, P < 0.05 each). As compared to subjects with normal LV function and mass-index (control), subjects with LV dysfunction (LV fractional shortening < 28%) or hypertrophy (LV mass-index > 110 g/m2 in women and > 134 g/m2 in men) were characterized by increased BNP. The increase in BNP associated with LV hypertrophy (n = 69, +101% versus control, P < 0.0001) was similar in magnitude to that associated with LV dysfunction (n = 39, +98% versus control, P < 0.03). These increases were markedly exceeded in subjects with severe LV dysfunction (n = 11, LV fractional shortening < 22%, BNP +197% versus control, P < 0.01), particularly in the presence of concomitant hypertrophy (n = 7, +227%, P < 0.01). The predictive values of BNP varied considerably with the degree of LV dysfunction and the presence or absence of concomitant LV hypertrophy. With 0.81, the highest area under the receiver operator characteristic curve was obtained for the detection of severe LV dysfunction and concomitant hypertrophy and sensitivity, specificity, positive and negative predictive value for this condition were 71, 86, 7 and 99.5%, respectively, for a cut-off of 34 pg/ml. CONCLUSIONS: The current study provides new insight into regulation and diagnostic value of BNP in middle-aged subjects and demonstrates important independent effects of LV function and mass upon BNP plasma concentrations. Although measurement of BNP cannot be recommended for the detection of marginally impaired LV function in the population, it may be helpful to suggest or exclude severe LV dysfunction with concomitant hypertrophy.     

Brain natriuretic peptide release in cardiac surgery patients

Brain natriuretic peptide (BNP) release is a marker of increased myocardial wall tension, which is elevated in patients with disturbed left ventricular function. As it is increasingly being used as a reliable marker for diagnosis, optimization of pharmacological treatment, and risk stratification, BNP measurement might be also relevant for patients undergoing cardiac surgery. Measured BNP levels can be used to predict postoperative complications and the risk of further cardiac events. Preoperative BNP levels support the decision for the timing of aortic valve replacement in asymptomatic severe aortic stenosis. An increase in BNP levels early predicts allograft rejection after cardiac transplantation or ineffective cardiac resynchronization therapy. Moreover, BNP levels can be used to differentiate between cardiac and non-cardiac reasons for acute dyspnea in the management of surgical patients. Finally, the application of recombinant human BNP seems to improve recovery after cardiac surgical procedures. Thus, BNP can be a helpful tool for monitoring and treating patients before, during, and after cardiac surgery to predict and improve the effectiveness of therapy and reduce hospitalization and costs.     

Plasma N-terminal pro-brain natriuretic peptide as a marker of right ventricular dysfunction in patients with tetralogy of Fallot after surgical repair

OBJECTIVE: Chronic heart failure is associated with neurohormonal activation that is not only related to outcome but is also a therapeutic target. We have attempted to demonstrate whether a similar pattern of neurohormonal activation exists in adult congenital heart disease (ACHD) and, if so, whether it relates to disease severity determined by cardiopulmonary exercise testing. METHODS AND RESULTS: Concentrations of N-terminal pro-atrial natriuretic peptide, N-terminal pro-brain natriuretic peptide (NT-proBNP), endothelin (ET)-1, renin, aldosterone, adrenalin, and noradrenalin were determined in 50 adults (mean age, 27.8 +/- 1.7 years [+/- SEM]; 26 women) with tetralogy of Fallot (TOF) after surgical repair (New York Heart Association functional class 1.1 +/- 0.1). One hundred age- and sex-matched healthy blood donors served as a control group for NT-proBNP determination. Dimensions of ventricles, left ventricular pump function, and estimated right ventricular (RV) systolic pressure were determined by echocardiography. Maximum oxygen uptake (V(O2max) was measured in all patients using spiroergometry. TOF patients had elevated levels of NT-proBNP compared with healthy individuals: NT-proBNP (women: 180 pg/mL vs 43 pg/mL, and men: 147 pg/mL vs 32 pg/mL; p < 0.0001) and ET-1 (2.5 fmol/L vs 0.7 fmol/L). There was a significant correlation of NT-proBNP to dimension and estimated peak systolic pressure of the RV as well as impairment of V(O2max). CONCLUSIONS: RV dysfunction detected by echocardiography and plasma NT-proBNP determination in asymptomatic or minimally symptomatic TOF patients correlates well with their cardiopulmonary exercise capacity. Thus, these simple and noninvasive screening methods can be used additionally to stratify ACHD patients with impaired cardiac function before they become clinically symptomatic.     

B-type natriuretic peptide: practical diagnostic use for evaluating ventricular dysfunction

Assessment of brain natriuretic peptide levels may provide important information that can be used in the evaluation of patients with dyspnea and follow-up of heart failure. Brain natriuretic peptide levels have been shown to be useful for evaluating patients in the emergency department and for evaluating patients complaining of dyspnea in the outpatient setting. Brain natriuretic peptide assessment also provides an adjunct to diagnosis of both systolic and diastolic dysfunction, has prognostic value for heart failure and in acute coronary syndromes, and may be a useful measure to guide therapy. Further work needs to be done to establish the best type of assay to use, to determine the optimal cutoff point for what is considered abnormal, and to determine how conditions other than ventricular dysfunction affect brain natriuretic peptide levels.