Lung congestion in chronic heart failure: haemodynamic, clinical, and prognostic implications

Abstract

Aims The goal of the study was to examine the prognostic impact, haemodynamic and clinical features associated with lung congestion in patients with chronic heart failure (HF). Methods and results HF patients (n = 186) and HF‐free controls (n = 21) underwent right heart catheterization, echocardiography, pulmonary function testing and chest radiography that was blindly scored for the presence and severity of lung oedema. Lung congestion correlated directly with pulmonary vascular resistance (PVR, P = 0.004) and inversely with pulmonary artery (PA) compliance (P < 0.001) and the diffusion limit for carbon monoxide (DLCO, P = 0.009). Compared with dry lung HF, wet lung HF patients (congestion score > median) had 25% lower PA compliance and 25–35% higher PVR, transpulmonary gradients and PA pressures (40 vs. 32 mmHg, P < 0.001) despite marginally higher PA wedge pressure (PAWP; 22 vs. 19 mmHg, P = 0.002). Wet lung HF patients displayed more right ventricular (RV) dilatation and dysfunction, more restrictive ventilation and greater reduction of DLCO. The strongest correlates of lung congestion were NT‐proBNP, haemoglobin, albumin, and glomerular filtration, all surpassing PAWP. After a median of 333 days (interquartile range 80–875), 59 patients (32%) died. Lung congestion was associated with reduced survival (P < 0.0001), even after adjusting for PAWP, NT‐proBNP, anaemia, CAD and renal dysfunction. Conclusion Interstitial lung oedema is associated with pulmonary vascular disease, RV overload and dysfunction and increased mortality in HF. These data reinforce the importance of aggressive decongestion in HF and suggest that novel agents aimed at reducing lung water may help to deter progression of pulmonary vascular disease and biventricular HF.

Phenotype-Specific Treatment of Heart Failure With Preserved Ejection Fraction

“…Impairments in pulmonary function predict incident development of HFpEF independent of cardiac function 140 . Patients with HFpEF display gas exchange abnormalities manifest by reduced alveolar capillary membrane conductance 141,142 . These impairments become more dramatic during exercise owing to high LV filling pressures during stress 141 .…”

Physiology of the lung in idiopathic pulmonary fibrosis

“…9% of patients with mild to moderate IPF and left ventricle ejection fraction ⩾40% have increased pulmonary artery wedge pressure, indicating occult heart failure [87]. In terms of lung function, heart failure can be associated with restriction, obstruction, reduced DLCO [106,107] and PH [108]. Heart failure with preserved ejection fraction is associated with reduced DLCO [109].…”

Lung fluid clearance in chronic heart failure patients

“…Lung water in CHF is increasingly recognised as a complex but critical component of the CHF syndrome which is incompletely understood pathophysiologically [10] and has been historically under recognised. Indeed, in recent clinical studies of discharge decompensated CHF, the presence of congestion on chest X-ray or via increased ultrasound B-lines is independently predictive of poor clinical outcome (hospitalisation and mortality) [10,11].…”

“…Indeed, in recent clinical studies of discharge decompensated CHF, the presence of congestion on chest X-ray or via increased ultrasound B-lines is independently predictive of poor clinical outcome (hospitalisation and mortality) [10,11].…”

“…Whether the clinically important presence of ongoing excess lung water in decompensated CHF represents a failure adequate lung fluid clearance or an issue of timing in the dynamic decompensated state is unknown [10,11]. The model of increased Pmv resulting in increased fluid influx balanced by increased fluid clearance does not hold in models of acute heart failure, or acute rise in Pmv, where alveolar fluid clearance has been found to decrease and pulmonary oedema manifest [13,[16][17][18].…”