Natriuretic peptides for the prediction of severely impaired peak VO2 in patients with lung disease

Relationship between NT-proBNP, echocardiographic abnormalities and functional status in patients with subclinical siabetic cardiomyopathy

INTRODUCTION

Persons with diabetes are at risk for developing a cardiomyopathy through several pathophysiological mechanisms independent of traditional risk factors for heart failure. Among those with diabetic cardiomyopathy (DbCM), the relationship between natriuretic peptides, cardiac structural abnormalities and functional capacity is largely unknown.

METHODS

In this prespecified subgroup analysis of the Aldose Reductase Inhibition for Stabilization of Exercise Capacity in Heart Failure (ARISE-HF) trial, 685 participants with asymptomatic DbCM underwent baseline echocardiography data, laboratory investigations, and functional assessments. Participants were stratified by N-terminal pro-B type natriuretic peptide (NT-proBNP) quartiles, and correlation with echocardiographic and functional parameters were assessed using Spearman correlation test.

RESULTS

The median NT-proBNP was 71 (Q1, Q3: 33, 135) ng/L. No association was observed between NT-proBNP concentrations and echocardiographic parameters of either diastolic or systolic dysfunction including global longitudinal strain, left ventricular ejection fraction, left ventricular mass index, left atrial volume index, E/E', or right ventricular systolic pressure. In contrast, NT-proBNP was significantly correlated with overall Kansas City Cardiomyopathy Questionnaire score (rho = - 0.10; p = 0.007), the Physical Activity Scale in the Elderly (rho = - 0.12; p = 0.004), duration of cardiopulmonary exercise testing (rho = - 0.28; p < 0.001), peak VO2 (rho = - 0.26; p < 0.001), and ratio of minute ventilation/carbon dioxide production (rho = 0.12; p = 0.002). After adjustment for known confounders, the correlation with Physical Activity Scale in the Elderly and overall Kansas City Cardiomyopathy Questionnaire score was no longer significant.

CONCLUSION

Among patients with subclinical DbCM, elevated NT-proBNP concentrations are associated with worse health status, lower activity levels, and reduced functional capacity, but not with cardiac structural abnormalities. These findings suggest that regardless of cardiac structural abnormalities, biomarker concentrations reflect important deterioration in functional capacity in affected individuals.

TRIAL REGISTRATION

ARISE-HF, NCT04083339 Date Registered August 23, 2019.

Diastolic Dysfunction Contributes to Impaired Cardiorespiratory Fitness in Patients with Lung Cancer and Reduced Lung Function Following Chest Radiation

Cardiorespiratory fitness (CRF) is a robust and independent predictor of cardiovascular health and overall mortality. Patients with lung cancer often have chronic lung disease, contributing to impaired CRF. Radiation to the heart during lung cancer treatment may further reduce CRF. The determinants of CRF in this population are not well understood. We prospectively evaluated 12 patients with lung cancer without known cardiovascular disease with reduced lung function receiving curative intent thoracic radiotherapy to determine whether cardiac diastolic function, as assessed by Doppler echocardiography and N-terminal pro-brain natriuretic peptide (NTproBNP) levels, correlate with CRF measured by peak oxygen consumption (VO₂). Doppler-derived measures of diastolic function and serum NTproBNP levels inversely correlated with peak VO_2. In a multivariate regression model, NTproBNP was the strongest independent variable associated with peak VO₂. These results suggest that diastolic dysfunction further contributes to reduced CRF in patients with lung cancer who have received radiotherapy.

Left Atrial Structure and Function in Heart Failure with Preserved Ejection Fraction: A RELAX Substudy

Given the emerging recognition of left atrial structure and function as an important marker of disease in heart failure with preserved ejection fraction (HF-pEF), we investigated the association between left atrial volume and function with markers of disease severity and cardiac structure in HF-pEF. We studied 100 patients enrolled in the PhosphdiesteRasE-5 Inhibition to Improve CLinical Status and EXercise Capacity in Diastolic Heart Failure (RELAX) trial who underwent cardiac magnetic resonance (CMR), cardiopulmonary exercise testing, and blood collection before randomization. Maximal left atrial volume index (LAVi; N = 100), left atrial emptying fraction (LAEF; N = 99; including passive and active components (LAEFP, LAEFA; N = 80, 79, respectively) were quantified by CMR. After adjustment for multiple testing, maximal LAVi was only associated with age (ρ = 0.39), transmitral filling patterns (medial E/e' ρ = 0.43), and N-terminal pro-BNP (NT-proBNP; ρ = 0.65; all p<0.05). Lower LAEF was associated with older age, higher transmitral E/A ratio and higher NT-proBNP. Peak VO2 and VE/VCO2 slope were not associated with left atrial structure or function. After adjustment for age, sex, transmitral E/A ratio, CMR LV mass, LV ejection fraction, and creatinine clearance, NT-proBNP remained associated with maximal LAVi (β = 0.028, p = 0.0007) and total LAEF (β = -0.033, p = 0.001). Passive and active LAEF were most strongly associated with age and NT-proBNP, but not gas exchange or other markers of ventricular structure or filling properties. Left atrial volume and emptying function are associated most strongly with NT-proBNP and diastolic filling properties, but not significantly with gas exchange, in HFpEF. Further research to explore the relevance of left atrial structure and function in HF-pEF is warranted.

Relationship Between Prohormone Brain Natriuretic Peptide (NT-proBNP) Level and Severity of Pulmonary Dysfunction in Patients With Chronic Congestive Heart Failure

Introduction: Congestive heart failure (CHF) is a common disease and its prevalence is increasing in industrialized countries. NT-proBNP measurement is an established diagnostic test for diagnosis of CHF in patients who present to emergency room with acute dyspnea. The primary object of this study was to determine the relationship between levels of brain natriuretic peptide precursor and severity of lung function impairment in patients with chronic CHF.

Methods: This cross-sectional and analytical study that performed in Tuberculosis and Lung Disease Research Center of Tabriz University of Medical Sciences on 95 patients with chronic heart failure, and relation between NT-proBNP levels and pulmonary function parameters were examined.

Results: Sixty-four patients were male and 31 were female. The average age of male and females was 62.90 ± 11.54 and 61.61 ± 11.98 years, respectively. A significant inverse linear correlation was found between NT-proBNP and FEV1 (P < 0.001, r = -0.367), FVC (P < 0.001, r = -0.444), TLC (P = 0.022, r = -0.238), maximal midexpiratory flow (MMEF) (P = 0.047, r = -0.207) and left ventricular ejection fraction (LVEF) (P < 0.001, r = -0.461). A significant positive linear correlation was found between NT-proBNP and FEV1/FVC (P = 0.013, r = 0.257), RV/TLC (P = 0.003, r=0.303) and 5 Hz Raw (r = 0.231, P = 0.024).

Conclusion: This study showed that, both restrictive and obstructive ventilator impairments can occur in chronic CHF and as NT-proBNP increases appropriate to hemodynamic deterioration, pulmonary dysfunction increases.