B-type natriuretic peptide strongly reflects diastolic wall stress in patients with chronic heart failure: comparison between systolic and diastolic heart failure

The effects of continuous positive airway pressure on plasma brain natriuretic peptide concentrations in patients presenting with acute cardiogenic pulmonary edema with preserved left ventricular systolic function

BACKGROUND

It has been established that plasma brain natriuretic peptide (BNP) concentrations in patients with acute cardiogenic pulmonary edema (ACPE) increase in proportion to heart failure.

OBJECTIVES

The aim of this study is to assess the effects of continuous positive airway pressure (CPAP) treatment on plasma BNP concentrations in patients presenting with ACPE with preserved left ventricular (LV) systolic function.

METHODS

This was a prospective, observational single-center study in the emergency unit of Valduce Hospital. Twelve patients (group A) presenting with ACPE and preserved LV ejection fraction and 14 patients (group B) with systolic heart dysfunction (LV ejection fraction <45%) underwent CPAP (10 cm H(2)O) through a face mask and standard medical therapy. Plasma BNP concentrations were collected immediately before CPAP and 3, 6, and 24 hours after treatment. All patients underwent a morphological echocardiographic investigation shortly before CPAP.

RESULTS

Three hours after admission, BNP significantly decreased in patients with ACPE and preserved LVEF (from 998 + or - 467 pg/mL to 858 + or - 420 pg/mL; P < .05), whereas in those with systolic dysfunction, BNP was higher than during baseline (from 1352 + or - 473 pg/mL to 1570 + or - 595 pg/mL; P < .05).

CONCLUSIONS

The preliminary results of the present study show that CPAP, after 3 hours, lowers BNP levels in patients with ACPE and preserved LV systolic function compared with patients affected by systolic ACPE dysfunction where BNP levels do not change significantly.

Interpretation and use of natriuretic peptides in non-congestive heart failure settings

Natriuretic peptides (NPs) have been found to be useful markers in differentiating acute dyspneic patients presenting to the emergency department (ED) and emerged as potent prognostic markers for patients with congestive heart failure (CHF). The best-established and widely used clinical application of BNP and NT-proBNP testing is for the emergent diagnosis of CHF in patients presenting with acute dyspnea. Nevertheless, elevated NPs levels can be found in many circumstances involving left ventricular (LV) dysfunction or hypertrophy; right ventricular (RV) dysfunction secondary to pulmonary diseases; cardiac inflammatory or infectious diseases; endocrinology diseases and high output status without decreased LV ejection fraction. Even in the absence of significant clinical evidence of volume overload or LV dysfunction, markedly elevated NP levels can be found in patients with multiple comorbidities with a certain degree of prognostic value. Potential clinical applications of NPs are expanded accompanied by emerging reports regarding screening the presence of secondary cardiac dysfunction; monitoring the therapeutic responses, risk stratifications and providing prognostic values in many settings. Clinicians need to have expanded knowledge regarding the interpretation of elevated NPs levels and potential clinical applications of NPs. Clinicians should recognize that currently the only reasonable application for routine practice is limited to differentiation of acute dyspnea, rule-out-diagnostic-tests, monitoring of therapeutic responses and prognosis of acute or decompensated CHF. The rationales as well the potential applications of NPs in these settings are discussed in this review article.

Brain natriuretic peptide and the athlete's heart: a pilot study

BACKGROUND

The role of brain natriuretic peptide (BNP) in differentiating the athlete's heart from maladaptive cardiac hypertrophy is unclear.

METHODS

To address this issue, an integrated M mode, two-dimensional B mode and Doppler echocardiographical study were performed and plasma BNP levels were measured in 25 strength athletes, 25 patients with established hypertrophic cardiomyopathy (HCM) and 25 healthy volunteers.

RESULTS

Among athletes, BNP levels correlated negatively with the total training time (r = -0.79, p = 0.002) and positively with ejection fraction (r = 0.58, p = 0.049) and fractional shortening (r = 0.57, p = 0.049). A BNP cut-off value of 11.8 pg/ml had 88% specificity and 74% negative predictive value for the exclusion of HCM.

CONCLUSIONS

Brain natriuretic peptide might be useful as a preparticipation screening test in athletes.

Relevance of short-term variation of B-type natriuretic peptide in patients with clinically stable heart failure

BACKGROUND

In patients with clinically stable chronic heart failure, circulating B-type natriuretic peptide (BNP) levels may exhibit considerable variation over a period of a few days. The aim of this study was to evaluate the clinical impact of this phenomenon.

METHODS

In 23 patients with clinically stable mild-to-moderate systolic heart failure [median (interquartile range) 72 (64-77) years, left ventricular ejection fraction 30 (27-40)%] and a history of previous hospitalization for heart failure, BNP was measured at two time points [T1 and T2, interval 5 (3-7) days] for calculation of the absolute change in BNP concentrations between T1 and T2 (DeltaBNP; irrespective of whether there was a decrease or increase). Follow-up for rehospitalization was 436 (407-458) days.

RESULTS

In the group overall, DeltaBNP was 26 (9-116) pg/ml [19 (10-28)% of the value at T1]. During follow-up, 8/23 (35%) patients were rehospitalized. BNP concentrations at T1 [340 (187-533) vs. 210 (108-606) pg/ml; P = 0.33] and T2 [328 (125-491) vs. 259 (89-536) pg/ml; P = 0.51] were similar in patients who were rehospitalized and those who were not; however, DeltaBNP was higher in patients requiring rehospitalization [98 (36-186) vs. 19 (6-93) pg/ml; P = 0.04]. Patients with DeltaBNP <26 pg/ml had a longer rehospitalization-free survival than those with DeltaBNP > or = 26 pg/ml (log rank P = 0.02). Sensitivity and specificity of DeltaBNP > or = 26 pg/ml for the prediction of rehospitalization were 88% and 67% respectively.

CONCLUSIONS

In this small study among patients with clinically stable heart failure, higher DeltaBNP over a period of a few days was associated with a higher likelihood of rehospitalization during follow-up.

Characterization of Cardiac Brain Natriuretic Peptide Release in Patients With Paroxysmal Atrial Fibrillation Undergoing Left Atrial Ablation

Background— Paroxysmal atrial fibrillation (PAF) is associated with elevated levels of brain natriuretic peptide (BNP). The exact cardiac source and implications of this are currently unknown, as are the effects of left atrial ablation on cardiac BNP release. We sought to investigate BNP levels at different cardiac sites in PAF patients before and after left atrial ablation and compare these with a non–atrial fibrillation control cohort.

Methods and Results— Twenty PAF patients (52�10 years, 70% men; left ventricular ejection fraction, 55�3%) undergoing ablation were studied, BNP levels were measured at different cardiac sites before and after ablation and compared with a control cohort undergoing ablation for left lateral accessory pathways (10 patients, 41�11 years; left ventricular ejection fraction, 55�4%). In both cohorts, the coronary sinus BNP levels were the greatest. The PAF cohort had significantly greater BNP levels than the control cohort at all sites before and after ablation. Ablation of the left atrium was associated with a significant decrease in coronary sinus BNP levels ( P =0.05) and transcardiac BNP gradient ( P =0.03). This was not observed in the control cohort.

Conclusions— BNP levels are elevated in PAF, with the highest levels in the coronary sinus. Ablation of the left atrium was associated with an immediate decrease of BNP levels, implicating this as the source.

Simultaneous estimation of NT-proBNP on top to mitral flow Doppler echocardiography as an accurate strategy to diagnose diastolic dysfunction in HFNEF

BACKGROUND

Conventional echocardiography has limited accuracy in detecting diastolic dysfunction and NT-proBNP is known to be a reliable biomarker to rule out heart failure. Therefore NT-proBNP on top to conventional mitral flow Doppler might improve the diagnostic of diastolic dysfunction in patients with heart failure despite normal EF (HFNEF) without using tissue Doppler.

METHODS AND RESULTS

Diastolic function of 46 patients with HFNEF was determined by pressure-volume loop obtained by conductance-catheter measurements. LV stiffness correlated with the amount of collagen types I and III analyzed from endomyocardial biopsies (EMBs). NT-proBNP plasma levels correlated with LV stiffness, LVEDP and the collagen amount from EMBs (p<0.01). In another set of patients with HFNEF (n=107, 53 [45-62] years), diastolic dysfunction was confirmed by left and/or right heart catheterization. Their Doppler indices and plasma marker NT-proBNP values were compared with those of 73 controls (186 [70-342] vs 54[30-75] pg/ml, p<0.001). Mitral flow Doppler was impaired in 70/107 (65%) of the HFNEF. When additional criterium NT-proBNP>125 pg/ml was used 96/107 (90%) patients with impaired diastolic function were recognized. Sensitivity of tissue Doppler indices E'/A' and E/E' were improved by 4-6% using NT-proBNP on top. NT-proBNP recognized HFNEF patients with higher hospitalization rate indicated by phone questionnaire, whereas Doppler indices alone did not.

CONCLUSION

Plasma NT-proBNP levels are associated with increased LV stiffness and cardiac collagen content. On top measurements of plasma NT-proBNP improve the echocardiography diagnostic of diastolic function and prognostic of rehospitalization in HFNEF.

Baseline plasma NT-proBNP and clinical characteristics: results from the irbesartan in heart failure with preserved ejection fraction trial

BACKGROUND

N-terminal B type natriuretic peptide (NT-proBNP) is usually elevated in heart failure (HF) patients with reduced ejection fraction (EF). Less is known about NT-proBNP in HF with preserved EF (HF-PEF). We measured baseline NT-proBNP in 3562 HF-PEF enrolled patients in the Irbesartan in Heart Failure with Preserved Ejection Fraction trial.

METHODS AND RESULTS

Patients with EF >or=45%, age >or=60 years, and either New York Heart Association (NYHA) II-IV symptoms with HF hospitalization (HFH) within 6 months or NYHA III-IV symptoms with corroborative evidence of HF or structural changes associated with HF-PEF. NT-proBNP (pg/mL) measured centrally using the Elecsys proBNP assay (Roche). Mean age 72 +/- 7 years, 60% were women, the investigator indicated HF etiology was hypertension in 64%; the majority were in NYHA III. Medications included diuretics in 82%, angiotensin-converting enzyme inhibitor in 26%, beta-blocker in 59%, and spironolactone in 15%. Median NT-proBNP was 341 pg/mL (interquartile range 135 to 974 pg/mL) and geometric mean was 354 pg/mL. In multivariate analysis, the baseline characteristics most strongly associated with higher NT-proBNP levels were atrial fibrillation (ratio of geometric mean 2.59, P < .001), NYHA IV symptoms (1.52, P < .001), lower estimated glomerular filtration rate (1.44, P < .001), and HFH hospitalization within 6 months (1.37, P < .001).

CONCLUSIONS

Most HF-PEF patients have elevated NT-proBNP levels. The NT-proBNP concentrations were related to baseline characteristics generally associated with worse outcomes for HF patients.

Prognostic value of B-type natriuretic peptide for cardiovascular events independent of left ventricular end-diastolic pressure

BACKGROUND

B-type natriuretic peptide (BNP) correlates with left ventricular (LV) end-diastolic pressure (LVEDP) and predicts cardiovascular events. We sought to determine whether BNP has prognostic value independent of LVEDP.

METHODS

Eligible patients were referred for coronary angiography between March 15, 2002, and April 30, 2008, at a single institution. Inclusion criteria were having BNP, LV ejection fraction (EF), and LVEDP measured within 24 hours of the angiogram. The predictive value of BNP for events independent of LVEDP, EF, and other confounders was determined.

RESULTS

The study population (n = 1,059) was followed for a mean of 1.8 +/- 1.7 years. The mean age was 63 +/- 13 years. The median BNP value was 182 pg/mL; 59% of patients had LVEDP > or =16 mm Hg. B-type natriuretic peptide and LVEDP had a modest but statistically significant correlation (r = 0.24, P < .0001). After adjustment for LVEDP and EF, the hazard ratio for the composite outcome of heart failure admissions and death was 1.37 (1.21-1.55, P < .0001) per unit increase in log BNP. After adjustment for BNP and EF, LVEDP did not predict heart failure admissions and death (hazard ratio 1.05 [0.95-1.10], per 5-mm Hg increase, P = .30). Those with BNP value below the median had longer event-free survival as compared to those with BNP value above the median, regardless of the LVEDP strata (log-rank P < .0001 for LVEDP > or =16 and <16 mm Hg).

CONCLUSION

B-type natriuretic peptide has prognostic value independent of LVEDP in this cohort with suspected coronary artery disease, suggesting this biomarker is not just a prognostic surrogate for elevated LV filling pressure.

Amino terminal pro B-type natriuretic peptide levels are elevated in the cord blood of neonates with congenital heart defect

This prospective study investigates whether amino terminal proB-type natriuretic peptide (NT-proBNP) levels are elevated in neonates with congenital heart defect (CHD). NT-proBNP levels in the umbilical cord blood of 60 neonates with prenatally diagnosed CHD, in the cord blood of 200 control subjects, and in the plasma of the respective mothers were analyzed using an automated enzyme immunoassay. NT-proBNP concentrations in the cord blood of the CHD group were significantly elevated compared with controls [median (range): 158 pg/mL (378-3631 pg/mL) and 626 pg/mL (153-2518 pg/mL); p value <0.001]. The NT-proBNP concentrations of the newborns and their mothers did correlate neither in the CHD nor in the control group. In 54 patients with CHD, NT-proBNP levels were measured on the median 5th day of life. They showed a significant increase (median 1665 pg/mL and 19222 pg/mL; p < 0.001). NT-proBNP levels in the cord blood of neonates with CHD are significantly elevated and show a marked increase in the first week of life. Furthermore, this study confirms previously published reference intervals of NT-proBNP in the cord blood of healthy neonates as well as the finding that there is no exchange of NT-proBNP across the placenta.

Elevated NT-pro-BNP levels are associated with comorbidities among HIV-infected women

HIV infection is associated with left ventricular (LV) dysfunction and accelerated atherosclerosis. These conditions result in elevation of plasma natriuretic peptide (NP) levels. The present study compares N-terminal-pro-BNP (NT-pro-BNP) levels in HIV-infected and -uninfected women and identifies factors influencing NT-pro-BNP levels in HIV-infected women. A total of 454 HIV-infected and 200 HIV-uninfected participants from the Women's Interagency HIV Study (WIHS) had NT-pro-BNP determination. Elevated NT-pro-BNP level was defined using previously determined age stratified cut-off values of >164 ng/liter (age <60 years) and >225 (age > or = 60 years). HIV-infected women were older (41.6 +/- 8.9 vs. 38.9 +/- 10.5 years, p < 0.01) and were more likely to have anemia, hepatitis C virus (HCV) antibodies, and kidney dysfunction than HIV-uninfected women. HIV-infected women had significantly higher NT-pro-BNP levels (142.4 +/- 524.8 vs. 73.6 +/- 115.1 ng/liter, p = 0.01) and a higher prevalence of elevated NT-pro-BNP (12.1% vs. 7.5%; p = 0.08). In univariate analyses, elevated NT-pro-BNP was significantly associated with age, systolic BP, hypertension, anemia, triglyceride levels, kidney disease, and HCV seropositivity, but not HIV infection. In multivariate analysis, elevated NT-pro-BNP levels were significantly associated with anemia and kidney function, and had a borderline association with the presence of HCV antibodies. Among HIV-infected women, NT-pro-BNP levels were not independently associated with measures of severity of infection or with HAART use. Although HIV-infected women have higher NT-pro-BNP levels than HIV-uninfected women, the differences are due to non-HIV factors such as anemia, kidney disease, and HCV coinfection. These findings suggest that natriuretic peptide levels are a global marker of comorbidity in the setting of HIV infection.

Utility of B-natriuretic peptide in the evaluation of left ventricular diastolic function and diastolic heart failure

PURPOSE OF REVIEW

Heart failure with preserved ejection fraction or diastolic heart failure is an increasingly prevalent disease process today. Natriuretic peptides have been shown to provide diagnostic and prognostic utility in patients with systolic heart failure. Here we review current publications exploring the relationship between B-natriuretic peptide (BNP) and diastolic dysfunction.

RECENT FINDINGS

Investigators have found significant correlations between echocardiographic parameters for diastolic dysfunction and serum BNP levels in diagnosing diastolic heart failure. This relationship is linear with respect to severity of left ventricular dysfunction. Newer echocardiographic modalities like tissue Doppler imaging provide measures of elevated left ventricular filling pressures, which are associated with higher plasma BNP levels. Admission and predischarge BNP levels in patients with decompensated diastolic heart failure have been prognostic with respect to in-hospital mortality, short-term mortality, and hospital readmission.

SUMMARY

Review of current literature shows that BNP can be useful in providing diagnostic and prognostic data in patients with symptomatic and asymptomatic diastolic dysfunction. These data, combined with other values such as echocardiographic indices and cardiovascular risk factors, can augment the sensitivity and specificity of BNP.

BNP at discharge in acute heart failure patients: is it all about volemia? A study using impedance cardiography to assess fluid and hemodynamic status

BACKGROUND

Besides hemodynamic parameters, several other variables have been associated to B-type natriuretic peptide (BNP) levels. Limited knowledge on BNP determinants in acute heart failure (HF) can undermine the interpretation of BNP levels.

METHODS AND RESULTS

To identify predictors of BNP levels, we evaluated 163 hospitalized acute HF patients. Thoracic fluid content (TFC) and hemodynamic parameters were measured by impedance cardiography at discharge. Patients were followed-up for 60 days for the occurrence of death/hospital admission. Median discharge BNP levels were 659.3 pg/ml. In multivariable linear regression analysis, TFC (β=0.043, 95% CI 0.024-0.062 per U/kΩ, p<0.001) was a powerful predictor of BNP levels, independently of known markers of HF severity like severe systolic dysfunction and discharge New York Heart Association class. Other independent predictors were: new onset HF, albumin, and body mass index. Sex, left cardiac work index, stroke index, hemoglobin, renal failure and discharge furosemide and lisinopril doses were associated to BNP only in univariate analysis. During follow-up, 45 (27.6%) patients were hospitalized or died. TFC (HR=1.047 (1.016-1.080) per U/kΩ increase, p=0.003) and BNP (HR=1.003 (1.001-1.004) per 10 pg/ml increase, p<0.001) were univariate predictors of the outcome, but in multivariate Cox regression analysis, only BNP was independently associated with prognosis.

CONCLUSION

Discharge BNP levels in acute HF patients reflected volemia and disease severity. Persistently high BNP levels during hospitalization should raise the possibility of remaining congestion, which could negatively influence prognosis. The utility of BNP as prognostic marker in HF may reside on its ability to reflect multiple underlying pathophysiological disturbances.

B-type natriuretic peptides and echocardiographic measures of cardiac structure and function

Echocardiography and the B-type natriuretic peptides (BNPs) provide powerful incremental assessment of cardiac function, clinical status, and outcome across the spectrum of cardiac disease. There is strong evidence to support their integrated use in the diagnosis and management of cardiovascular disease. Amino-terminal pro-B-type natriuretic peptide (NT-proBNP) or BNP may guide more effective use of echocardiography in screening for asymptomatic left ventricular dysfunction; Doppler echocardiography improves the accuracy of heart failure diagnosis in the setting of intermediate BNP or NT-proBNP levels. Combined assessment of peptides and echocardiography provides more powerful stratification of risk across all stages of heart failure, and integrated use of both tests may identify subjects with valvular disease at greatest risk for progression and guide decision-making for timely intervention.

Impact of Left Ventricular End-Diastolic Wall Stress on Plasma B-Type Natriuretic Peptide in Heart Failure with Chronic Kidney Disease and End-Stage Renal Disease

Background: Plasma B-type natriuretic peptide (BNP) is a diagnostic and prognostic marker in heart failure (HF). Although renal function is reported as an important clinical determinant, precise evaluations of the relationships of renal function with hemodynamic factors in determining BNP have not been performed. Therefore, we evaluated the association of plasma BNP concentrations with LV end-diastolic wall stress (EDWS) in a broad range of HF patients including those with chronic kidney disease (CKD) and end-stage renal disease (ESRD).

Methods: In 156 consecutive HF patients including those with CKD and ESRD, we measured plasma BNP and performed echocardiography and cardiac catheterization. LV EDWS was calculated as a crucial hemodynamic determinant of BNP.

Results: Plasma BNP concentrations increased progressively with decreasing renal function across the groups (P &lt; 0.01) and were correlated with LV EDWS (r = 0.47) in the HF patients overall. This relationship was also present when patients were subdivided into systolic and diastolic HF (P &lt; 0.01). In multivariable analysis, higher EDWS was associated with increased BNP concentration independently of renal dysfunction (P &lt; 0.01). Anemia, systolic HF, and decreased BMI also contributed to increased BNP concentrations.

Conclusions: These results suggest that LV EDWS is a strong determinant of BNP even in patients with CKD and ESRD. Anemia, obesity, and HF type (systolic or diastolic) should also be considered in interpreting plasma BNP concentrations in HF patients. These findings may contribute to the clinical management of HF patients, especially those complicated with CKD and ESRD.

Usefulness of plasma BNP levels as a marker of left ventricular wall stress in obese individuals

Plasma brain natriuretic peptide (BNP) level is known to reflect left ventricular wall stress (LVWS). Recent studies have shown that obese individuals have lower BNP levels. However, the usefulness of BNP level as a marker of LVWS in obese individuals remains unclear. This study examined whether BNP reflects LVWS even in obese individuals.This study enrolled 136 hospital inpatients who had suffered chronic heart failure (NYHA class I or II), or who had undergone a thorough examination for angina pectoris. On the basis of body mass index (BMI), we divided the inpatients into nonobese (< 25) and obese (> or = 25) groups. All BNP measurements, cardiac catheterizations, and echocardiographic examinations were carried out within 24 hours. Although no significant differences were found between the two groups in the hemodynamic parameters examined, including end-diastolic LVWS (LV-EDWS) and end-systolic LVWS (LV-ESWS), BNP levels were significantly lower in the obese group compared to the nonobese group. In the nonobese group, a definite correlation between LV-EDWS or LV-ESWS and BNP (r = 0.43, r = 0.46, respectively) was observed, whereas no correlation was found between LV-EDWS or LV-ESWS and BNP in the obese group (r = -0.09, r = 0.06, respectively). To explore the mechanism for suppressed BNP levels in obese individuals, the correlation of BNP with biochemical markers was analyzed. Statistical significance was found only between adiponectin and BNP (r = 0.44), implying that BNP or adiponectin might influence the plasma levels of the other.In conclusion, BNP levels cannot be used as a marker of LVWS in obese individuals.

Acute heart failure: How to evaluate left ventricular filling pressure in practice?

Heart failure is one of the most frequent reasons for hospitalization due to a cardiac event. In most instances, the main difficulty is how to accurately evaluate left ventricular filling pressure. It can be evaluated clinically, biologically and invasively. Although historically, invasive management has been the reference, it is being used less and less frequently and expertise in the technique is being lost. This paper discusses the strength and weaknesses of the different techniques for evaluating filling pressure in these patients, and the importance of this parameter for their optimal treatment.

Coronary flow reserve in idiopathic dilated cardiomyopathy: relation with left ventricular wall stress, natriuretic peptides, and endothelial dysfunction

Studies have demonstrated impaired coronary blood flow reserve (CBFR) in idiopathic dilated cardiomyopathy (IDCM). It was the aim of this study to examine the potential underlying mechanisms for CBFR reduction in patients with IDCM by Doppler ultrasound techniques. Forty-eight clinically stable patients with heart failure caused by IDCM (New York Heart Association classes 1-3) were evaluated by echocardiographic and Doppler techniques with the assessments of CBFR and brachial artery flow-mediated dilation (FMD). CBFR was estimated as the hyperemic (dipyridamole: 0.84 mg/kg in 10 minutes, intravenously) to resting coronary diastolic peak velocities ratio. N-terminal pro-brain natriuretic peptide (Nt-pro-BNP) plasma levels were measured at the time of the index echocardiogram. Left ventricular (LV) ejection fraction was 30% +/- 8%, and wall motion score index was 2.0 +/- 0.25. The best correlation with CBFR was found with LV wall thickness-to-cavity radius (r = 0.77, P < .0001). A strong correlation of log-transformed Nt-pro-BNP levels was observed with CBFR (r = -0.64; P < .0001). No significant correlation was documented between CBFR and FMD. The stepwise regression model showed that LV wall thickness-to-cavity radius was the strongest independent predictor of CBFR followed by New York Heart Association class and log-transformed Nt-pro-BNP leading to a cumulative R value of 0.82 (P < .0001). The results of the study indicate that by measuring variables related to LV end-diastolic wall stress, such as LV wall thickness-to-cavity radius and plasma Nt-proBNP, it is possible to have information about CBFR in patients with heart failure secondary to IDCM.

Incremental predictive value of pre-procedural N-terminal pro-B-type natriuretic peptide for short-term recurrence in atrial fibrillation ablation

The objective of this work was to assess the predictive value of pre-procedural N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in patients undergoing atrial fibrillation (AF) ablation. Seventy-three consecutive patients with AF (paroxysmal n = 49, persistent n = 24) and preserved left ventricular (LV) systolic function (LV ejection fraction > 45%) were prospectively enrolled in this study. All of the enrolled patients underwent catheter ablation after a measurement of their plasma NT-proBNP levels, and an echocardiographic examination with assessment of their LV diastolic function and left atrial(LA) volume. Patients with AF recurrence at 3 months had more persistent AF (P = 0.001), a higher LA volume index (P = 0.002), lesser decelerating times (DT) of mitral inflow (P = 0.014), and higher NT-proBNP levels (P < 0.001), when compared with patients with sinus rhythm restoration. The baseline log NT-proBNP correlated significantly with age (r = 0.26, P = 0.025), LA volume index (r = 0.41, P = 0.001), E/E' (r = 0.34, P = 0.007), DT (r = -0.34, P = 0.007), and E (r = 0.25, P = 0.04). The log NT-proBNP (HR 7.76, 95% CI 2.95-20.39, P < 0.001) was an independent predictor of AF recurrence. The measurement of NT-proBNP added incremental predictive value to standard indexes of LA size or diastolic function, including LA volume index and DT (P = 0.02). This study suggests the clinical utility of the level of NT-proBNP as an integrating marker of various risk factors, and as an incremental predictive marker for AF catheter ablation.

Heart failure and chronic obstructive pulmonary disease: diagnostic pitfalls and epidemiology

Heart failure (HF) and chronic obstructive pulmonary disease (COPD) are global epidemics incurring significant morbidity and mortality. The combination presents many diagnostic challenges. Clinical symptoms and signs frequently overlap. Evaluation of cardiac and pulmonary function is often problematic and occasionally misleading. Echocardiography and pulmonary function tests should be performed in every patient. Careful interpretation is required to avoid misdiagnosis and inappropriate treatment. Airflow obstruction, in particular, must be demonstrated when clinically euvolaemic. Very high and very low concentrations of natriuretic peptides have high positive and negative predictive values for diagnosing HF in those with both conditions. Intermediate values are less informative. Both conditions are systemic disorders with overlapping pathophysiological processes. In patients with HF, COPD is consistently an independent predictor of death and hospitalization. However, the impact on ischaemic and arrhythmic events is unknown. Greater collaboration is required between cardiologists and pulmonologists to better identify and manage concurrent HF and COPD. The resulting symptomatic and prognostic benefits outweigh those attainable by treating either condition alone.

The use of natriuretic peptides in the intensive care unit

PURPOSE OF REVIEW

B-type natriuretic peptides are quantitative markers of heart failure (and/or cardiac stress) that summarize the extent of systolic and diastolic left ventricular dysfunction, valvular dysfunction, and right ventricular dysfunction. Based on the observation that heart failure is common albeit difficult to diagnose in the ICU, several studies have begun to evaluate the potential use of B-type natriuretic peptides in various ICU settings.

RECENT FINDINGS

Previous pilot studies have examined the use of B-type natriuretic peptide in the differential diagnosis of hypoxemic respiratory failure, to differentiate cardiogenic from noncardiogenic shocks or to predict fluid responsiveness, to assess myocardial dysfunction and prognosis in patients with severe sepsis, and to predict ventilatory weaning failure.

SUMMARY

Although previous studies were small, they highlight the potential of using B-type natriuretic peptides as a noninvasive easily available tool to quantify cardiac stress.

The use of B-type natriuretic peptides in the intensive care unit

B-type natriuretic peptide levels are quantitative markers of cardiac stress and heart failure that summarize the extent of systolic and diastolic left ventricular dysfunction, valvular dysfunction, and right ventricular dysfunction. Initial observational pilot studies have addressed 7 potential indications in the intensive care unit: identification of cardiac dysfunction, diagnosis of hypoxic respiratory failure, risk stratification in severe sepsis and septic shock, evaluation of patients with shock, estimation of invasive measurements, weaning from mechanical ventilation, as well as perioperative and postoperative risk prediction. Although additional studies are required to better define the clinical utility of B-type natriuretic peptide values in the intensive care unit, current data suggest that the diagnosis of hypoxic respiratory failure and timing of extubation seem to be the most promising indications.

The clinical and hemodynamic factors that influence the concentrations of biomarkers of myocyte injury measured by high sensitive assay PATHFAST

BACKGROUND

Subclinical myocyte injury plays an important role in the progression of congestive heart failure. However, the clinical and hemodynamic factors that influence the concentrations of biomarkers of myocyte injury have not been clarified.

METHODS

Blood was sampled during diagnostic cardiac catheterization from 108 consecutive patients without acute coronary syndrome and acute cardiac decompensation. The serum concentrations of B-type natriuretic peptide (BNP), cardiac troponin I (cTnI), creatine kinase (CK)-MB, and myoglobin were measured simultaneously by high sensitive PATHFAST assay. Single and multiple variable regression analyses were carried out in search of correlations between clinical and hemodynamic variables and concentrations of biomarkers.

RESULTS

By multiple variable analysis, hemoglobin concentration, pulmonary capillary wedge pressure (PCWP), left ventricular (LV) ejection fraction, and estimated glomerular filtration rate (GFR) were independently correlated with a BNP concentration ≥ median 72.1 pg/ml. The only factors independently correlated with a concentration of cTnI ≥ median 0.01 ng/ml were PCWP and estimated GFR. Cardiac index emerged as a single, powerful, independent correlate of CK-MB concentration ≥ median 0.66 ng/ml, and estimated GFR emerged as a single independent correlate of myoglobin concentration ≥ median 40.1 ng/ml.

CONCLUSIONS

Clinical and hemodynamic factors influence the concentrations of BNP, cTnI, CK-MB, and myoglobin. These factors should be considered when interpreting the concentrations of these biochemical markers.

Changes in tissue-Doppler echocardiographic assessment of left ventricular filling during NT-proBNP guided heart failure treatment titration: a pilot study

BACKGROUND

Although brain natriuretic peptide (BNP) and E/Ea are closely related in heart failure (HF) patients and may be helpful to guide HF therapy, the response of E/Ea to changes in BNP over several weeks of intensive HF treatment optimisation is unknown. This study was designed to investigate this relationship.

METHODS AND RESULTS

In 17 patients with decompensated HF, treatment was titrated to reduce the NT-proBNP level to <200pg/mL over 10 weeks. Paired NT-proBNP measurements and echocardiograms were performed at two weekly intervals during the study. Treatment titration was associated with a reduction in E/Ea (17.6+/-6.8S.D. to 13.7+/-5.0S.D., p=0.018) in keeping with the reduction in NT-proBNP (median 603 [S.E. 561] to 311 [S.E. 235], p=0.045). This relationship remained in those who responded to titration (reduction in NT-proBNP of >or=50%), and those who did not. The overall change in E/Ea was similar to the changes observed in NT-proBNP in each group however there appeared to be temporal differences in the changes in E/Ea and NT-proBNP.

CONCLUSION

This pilot study demonstrates that the E/Ea decreases after NT-proBNP guided HF therapy. E/Ea may be a complementary target for HF therapy optimisation; this hypothesis should be further evaluated in larger scale randomised trials.

Usefulness of N-terminal pro-brain natriuretic Peptide and brain natriuretic peptide to predict cardiovascular outcomes in patients with heart failure and preserved left ventricular ejection fraction

More than 40% of patients hospitalized with heart failure have preserved left ventricular ejection fraction (HF-PLVEF) and are at high risk for cardiovascular (CV) events. The purpose of this study was to determine the value of N-terminal pro-brain natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) in predicting CV outcomes in patients with HF-PLVEF. Participants with an ejection fraction >40% in the prospective CHARM Echocardiographic Substudy were included in this analysis. Plasma NT-proBNP levels were measured, and 2 cut-offs were selected prospectively at 300 pg/ml and 600 pg/ml. BNP cut-off was set at 100 pg/ml. Clinical characteristics were recorded, and systolic and diastolic function were evaluated by echocardiography. The primary substudy outcome was the composite of CV mortality, hospitalization for heart failure, and myocardial infarction or stroke. A total of 181 patients were included, and there were 17 primary CV events (9.4%) during a median follow-up time of 524 days. In a model including clinical characteristics, echocardiographic measures, and BNP or NT-proBNP, the composite CV event outcome was best predicted by NT-proBNP >300 pg/ml (hazard ratio 5.8, 95% confidence intervals [CI] 1.3 to 26.4, p = 0.02) and moderate or severe diastolic dysfunction on echocardiography. When NT-proBNP >600 pg/ml was used in the model, it was the sole independent predictor of primary CV events (hazard ratio 8.0, 95% CI 2.6 to 24.8, p = 0.0003) as was BNP >100 pg/ml (hazard ratio 3.1, 95% CI 1.2 to 8.2, p = 0.02) in the BNP model. In conclusion, both elevated NT-proBNP and BNP are strong independent predictors of clinical events in patients with HF-PLVEF.

Inflammatory pathways in patients with heart failure and preserved ejection fraction

Immune activation is well established in patients with chronic heart failure and reduced ejection fraction (HF and reduced EF) and is associated with an impaired prognosis. Patients with heart failure and preserved ejection fraction (HF and preserved EF) have an impaired prognosis as well. It is not known whether they have signs of immune activation.

METHODS

We studied patients with HF and preserved EF (n=17, NYHA II [n=7]/III [n=10]) and patients with HF and reduced EF (n=17 NYHA II [n=1]/III [n=16]) and 20 controls. Echocardiography demonstrated preserved ejection fraction (LVEF 59+/-9%), but LV hypertrophy in patients with preserved EF as compared with patients with reduced EF (LVEF 23+/-5%). We evaluated levels of TNFalpha, its receptors (sTNFR-1 and 2), IL-6, IL-10 and NT-proBNP.

RESULTS

TNFalpha, was highest in HF with reduced EF (2.87+/-0.65 vs 1.67+/-0.58 pg/mL, p<0.001) compared to preserved EF and similar between HF with preserved EF and controls. However, sTNFR1 (1618+/-384 vs 1017+/-302 pg/mL, p<0.001) and sTNFR2 levels (3554+/-916 vs 2041+/-586 pg/mL, p<0.001) in HF with preserved EF were significantly higher compared with controls. The same was true for IL-6, IL-10 and NT-proBNP. The highest cytokine and NT-proBNP levels were present in HF with reduced EF. There was a negative correlation between TNFalpha, and LVEF (r=- 0.700; p<0.0001) and positive correlations between sTNFR1 and 2 with NT-proBNP.

CONCLUSION

Patients with HF and preserved EF already show signs of systemic-immune activation which may contribute to the impaired prognosis and the progression to HF with reduced EF.

State of the art: using natriuretic peptide levels in clinical practice

Natriuretic peptide (NP) levels (B-type natriuretic peptide (BNP) and N-terminal proBNP) are now widely used in clinical practice and cardiovascular research throughout the world and have been incorporated into most national and international cardiovascular guidelines for heart failure. The role of NP levels in state-of-the-art clinical practice is evolving rapidly. This paper reviews and highlights ten key messages to clinicians: 1) NP levels are quantitative plasma biomarkers of heart failure (HF). 2) NP levels are accurate in the diagnosis of HF. 3) NP levels may help risk stratify emergency department (ED) patients with regard to the need for hospital admission or direct ED discharge. 4) NP levels help improve patient management and reduce total treatment costs in patients with acute dyspnoea. 5) NP levels at the time of admission are powerful predictors of outcome in predicting death and re-hospitalisation in HF patients. 6) NP levels at discharge aid in risk stratification of the HF patient. 7) NP-guided therapy may improve morbidity and/or mortality in chronic HF. 8) The combination of NP levels together with symptoms, signs and weight gain assists in the assessment of clinical decompensation in HF. 9) NP levels can accelerate accurate diagnosis of heart failure presenting in primary care. 10) NP levels may be helpful to screen for asymptomatic left ventricular dysfunction in high-risk patients.

BNP and NT-proBNP predict echocardiographic severity of diastolic dysfunction

AIMS

To evaluate the best combination of clinical parameters and brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP), to predict diastolic dysfunction (DD) in heart failure with preserved left ventricular ejection fraction (HF-PLEF) as determined by Doppler-echocardiography.

METHODS AND RESULTS

HF patients with EF >40% in the CHARM Echocardiographic Substudy were included and classified to have normal diastolic function, or mild, moderate or severe diastolic dysfunction. Plasma BNP and NT-proBNP levels were measured and relevant clinical characteristics recorded. 181 participants were included in this analysis, 72 (40%) had moderate to severe DD. A model including age, sex, BNP, body mass index, history of atrial fibrillation, coronary artery disease, diabetes mellitus, hypertension and left atrial volume was highly predictive of moderate to severe DD; AUC 0.81 (0.73-0.88; p<0.0001). Similarly, substitution of BNP with NT-proBNP resulted in an AUC 0.79 (0.72-0.87; p<0.0001). In these models; BNP>100 pg/ml (OR 6.24 CI 2.42-16.09, p=0.0002), history of diabetes (OR 3.52 CI 1.43-8.70, p=0.006) and NT-proBNP >600 pg/ml (OR 5.93 CI 2.21-15.92, p=0.0004), history of diabetes mellitus (OR 2.75 CI 1.12-6.76, p=0.03) respectively remained independent predictors of DD in HF-PLEF.

CONCLUSIONS

Natriuretic peptides were the strongest independent predictors of DD, as determined by Doppler-echocardiography, in HF-PLEF.

Assessment of left ventricular dyssynchrony during development of heart failure by a novel program using ECG-gated myocardial perfusion SPECT

BACKGROUND

A novel program, "cardioGRAF", has been developed to analyze regional left ventricular (LV) systolic/diastolic function and dyssynchrony, so the present study aimed to use it confirm the presence of LV dyssynchrony, and to correlate LV function and dyssynchrony with plasma B-type natriuretic peptide (BNP) levels during the early to advanced stages of heart failure (HF).

METHODS AND RESULTS

Fourteen control subjects (G-C) and 50 patients (New York Heart Association functional class I: G-1, 21 patients; class II: G-2, 15 patients; and class III: G-3, 14 patients) were examined by ECG-gated myocardial perfusion single-photon emission computed tomography, using the new index of dyssynchrony, maximal difference (MD), which is the difference between the earliest and latest temporal parameters among 17 segments. First-third filling rate (FR) and the MD of time to peak FR revealing diastolic dyssynchrony were significantly different between G-C subjects and G-1 patients. Ejection fraction, peak ejection rate, peak FR, MD of time to end-systole, and MD of time to peak ejection rate were significantly correlated with plasma BNP levels.

CONCLUSION

Diastolic dyssynchrony was demonstrated even in the early stage of HF, but, although not correlated with the plasma BNP level, systolic dyssynchrony might affect it.

Correlation Between NT-pro BNP levels and left ventricular wall stress, sphericity index and extent of myocardial damage: a magnetic resonance imaging study

BACKGROUND

To determine the relationship between N-terminal pro-brain natriuretic peptide (NT-pro BNP) levels and left ventricular wall stress, sphericity index, function, and extent of myocardial damage in patients with coronary artery disease and abnormal left ventricular wall motion.

METHODS AND RESULTS

All patients underwent cardiac magnetic resonance imaging (CMR). Measurements of sphericity index and wall stress were performed. Percentages of myocardial scarring were calculated from delayed-enhancement images. Correlations between log NT-pro BNP levels and various parameters were evaluated. There were 125 patients with an average age of 62.6 +/- 9.6 years. Median levels of NT-proBNP were 1012 pg/mL. Average left ventricular ejection fraction (LVEF) was 37 +/- 14.4%. Log NT-proBNP levels had positive correlations with wall stress, sphericity index, left ventricular dimension, volume, mass, wall motion score, extent of myocardial scarring, and age, and had negative correlations with creatinine clearance, LVEF, stroke volume, and body size. Multiple linear regression analysis showed that diastolic and systolic wall stress and systolic sphericity index were independent predictors for log NT-proBNP levels.

CONCLUSIONS

NT-proBNP levels strongly correlated with left ventricular wall stress and moderately correlated with sphericity index.

Plasma N-terminal protype-B natriuretic peptide levels in risk assessment of patients with mitral regurgitation secondary to ischemic and nonischemic dilated cardiomyopathy

BACKGROUND

Functional mitral regurgitation (MR) is a factor affecting prognosis of patients with chronic left ventricular (LV) dysfunction. The aim of the study was to investigate whether the evaluation of plasma N-terminal protype-B natriuretic peptide (NT-proBNP) concentrations is useful for prognostic assessment of patients with functional MR due to either ischemic or nonischemic chronic LV dysfunction.

METHODS

Echocardiograms were obtained in 207 patients with chronic LV dysfunction (ejection fraction <or=45%) and secondary MR at color flow imaging. The NT-proBNP was measured at the time of the index echocardiogram. The MR was graded as mild when a small central jet <4 cm(2) or <20% of left atrial area or a vena contracta width <0.3 cm was present. It was considered moderate in the presence of signs of more-than-mild MR without criteria for severe MR. A vena contracta width >or=0.7 cm raised MR grade to severe. Median follow-up duration was 29 months.

RESULTS

The NT-proBNP levels increased significantly with MR severity. At multivariate analysis, NT-proBNP was an independent predictor of cardiac death (hazard ratio 2.17, CI 1.10-4.30, P = .026) and the most powerful predictor of cardiac death or heart failure-related hospitalization (hazard ratio 3.19, CI 1.89-5.37, P < .0001). A progressively worse outcome was apparent when patients were stratified by a graded increase in MR severity and by quartiles of NT-proBNP levels. Increased NT-proBNP concentrations and more-than-mild MR identified patients with the highest risk of cardiac mortality.

CONCLUSION

Assessment of plasma NT-proBNP allows for stratifying patients with functional MR regardless of their degree of valvular incompetence. Even in case of only mild or moderate MR, but increased NT-proBNP, patients have to face poor outcome.

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.

B-type natriuretic peptide and wall stress in dilated human heart

Background Although B-type natriuretic peptide (BNP) is used as complimentary diagnostic tool in patients with unknown thoracic disorders, many other factors appear to trigger its release. In particular, it remains unresolved to what extent cellular stretch or wall stress of the whole heart contributes to enhanced serum BNP concentration. Wall stress cannot be determined directly, but has to be calculated from wall volume, cavity volume and intraventricular pressure of the heart. The hypothesis was, therefore, addressed that wall stress as determined by cardiac magnetic resonance imaging (CMR) is the major determinant of serum BNP in patients with a varying degree of left ventricular dilatation or dysfunction (LVD). Methods A thick-walled sphere model based on volumetric analysis of the LV using CMR was compared with an echocardiography-based approach to calculate LV wall stress in 39 patients with LVD and 21 controls. Serum BNP was used as in vivo marker of a putatively raised wall stress. Nomograms of isostress lines were established to assess the extent of load reduction that is necessary to restore normal wall stress and related biochemical events. Results Both enddiastolic and endsystolic LV wall stress were correlated with the enddiastolic LV volume (r = 0.54, P < 0.001; r = 0.81, P < 0.001). LV enddiastolic wall stress was related to pulmonary pressure (capillary: r = 0.69, P < 0.001; artery: r = 0.67, P < 0.001). Although LV growth was correlated with the enddiastolic and endsystolic volume (r = 0.73, P < 0.001; r = 0.70, P < 0.001), patients with LVD exhibited increased LV wall stress indicating an inadequately enhanced LV growth. Both enddiastolic (P < 0.05) and endsystolic (P < 0.01) wall stress were increased in patients with increased BNP. In turn, BNP concentration was elevated in individuals with increased enddiastolic wall stress (>8 kPa: 587 +/- 648 pg/ml, P < 0.05; >12 kPa: 715 +/- 661 pg/ml, P < 0.001; normal < or =4 kPa: 124 +/- 203 pg/ml). Analysis of variance revealed LV enddiastolic wall stress as the only independent hemodynamic parameter influencing BNP (P < 0.01). Using nomograms with "isostress" curves, the extent of load reduction required for restoring normal LV wall stress was assessed. Compared with the CMR-based volumetric analysis for wall stress calculation, the echocardiography based approach underestimated LV wall stress particularly of dilated hearts. Conclusions In patients with LVD, serum BNP was increased over the whole range of stress values which were the only hemodynamic predictors. Cellular stretch appears to be a major trigger for BNP release. Biochemical mechanisms need to be explored which appear to operate over this wide range of wall stress values. It is concluded that the diagnostic use of BNP should primarily be directed to assess ventricular wall stress rather than the extent of functional ventricular impairment in LVD.

The relationship between long-term changes in plasma B-type natriuretic peptide levels and electrocardiographic findings

OBJECTIVES

Changes in B-type natriuretic peptide (BNP) and electrocardiographic (ECG) findings in an adult Japanese population were measured over a 5-year period, and the statistical relationships between these were evaluated.

METHODS

This was a longitudinal analysis in which data were collected on 353 subjects (135 men and 218 women) who had undergone general health checks in 1998 and 2003.

RESULTS

Data were examined by correlation coefficient and one-way analysis of covariance using repeated measurements. The correlation coefficient for BNP between 1998 and 2003 was 0.622 (P < 0.0001) for the men and 0.557 (P < 0.0001) for women. The changes in BNP over the same period were 13.71 +/- 26.06 (P < 0.0001) pg/ml in the men and 20.17 +/- 32.01 (P < 0.0001) pg/ml in the women. In 99 men and 145 women who had undergone ECG tests, with both normal and abnormal findings, visual inspections of changes in the ECG findings with respect to BNP changes were performed over the 5-year period. In men, both age and BNP significantly correlated with changes in ECG findings; however, in women, no significant correlation between BNP and changes in ECG findings was observed.

CONCLUSIONS

This regional longitudinal study revealed a gender difference in the relationship between long-term changes in BNP and ECG findings, suggesting that a 10 pg/ml or more increase in BNP in men over a 5-year period may a indicate worsening of cardiac function and the need for intervention.

BNP or NTproBNP? A clinician's perspective

Existing literature on two natriuretic peptides--B-type natriuretic peptide (BNP) and amino terminal pro-brain natriuretic peptide (NTproBNP)--is overwhelming. Both peptides are acknowledged markers for cardiac dysfunction. Most of the sources present data on either BNP or NTproBNP making the comparison difficult. This paper focuses on reviewing studies directly comparing two peptides in the setting of chronic and acute heart failure (HF) and coronary artery disease. Many concomitant diseases influence these two peptides to varying extent. These characteristics should be taken into consideration when interpreting results. For most practical purposes, BNP and NTproBNP are interchangeable, and can be used based on local preferences and availability. NTproBNP seems to be more advantageous for diagnosing mild HF or asymptomatic left ventricular dysfunction.

Role of left ventricular stiffness in heart failure with normal ejection fraction

BACKGROUND

Increased left ventricular stiffness is a distinct finding in patients who have heart failure with normal ejection fraction (HFNEF). To elucidate how diastolic dysfunction contributes to heart failure symptomatology during exercise, we conducted a study using an invasive pressure-volume loop approach and measured cardiac function at rest and during atrial pacing and handgrip exercise.

METHODS AND RESULTS

Patients with HFNEF (n=70) and patients without heart failure symptoms (n=20) were enrolled. Pressure-volume loops were measured with a conductance catheter during basal conditions, handgrip exercise, and atrial pacing with 120 bpm to analyze diastolic and systolic left ventricular function. During transient preload reduction, the diastolic stiffness constant was measured directly. Diastolic function with increased stiffness was significantly impaired in patients with HFNEF during basal conditions. This was associated with increased end-diastolic pressures during handgrip exercise and with decreased stroke volume and a leftward shift of pressure-volume loops during atrial pacing.

CONCLUSIONS

Increased left ventricular stiffness contributed to increased end-diastolic pressure during handgrip exercise and decreased stroke volume during atrial pacing in patients with HFNEF. These data suggest that left ventricular stiffness modulates cardiac function in HFNEF patients and suggests that diastolic dysfunction with increased stiffness is a target for treating HFNEF.