Right ventricular function and its coupling with the pulmonary circulation in acute heart failure
Authors: Barki M , Losito M , Caracciolo M.M , Bandera F , Rovida M , Alfonzetti E , Guazzi M 
Published: November 2020

Abstract

Background
The right ventricle (RV) is extremely sensitive to hemodynamic changes and increased impedance. In acute heart failure (AHF), the development of pulmonary venous congestion and the increase of left ventricular (LV) filling pressures favors pulmonary vascular adverse remodeling and ultimately RV dysfunction, leading to the onset of symptoms and to a further decay of cardiac dynamics.

Purpose
The aim of the study was to evaluate RV morphology and functional dynamics at admission and discharge in patients hospitalized for AHF, analyzing the role and the response to treatment of the RV and its coupling with pulmonary circulation (PC).

Methods
Eighty-one AHF patients (mean age 75.75±10.6 years, 59% males) were prospectively enrolled within 24–48 hours from admission to the emergency department (ED). In either the acute phase and at pre-discharge all patients underwent M-Mode, 2-Dimensional and Doppler transthoracic echocardiography (TTE), as well as lung ultrasonography (LUS), to detect an increase of extravascular lung water (EVLW) and development of pleural effusion. Laboratory tests were performed in the acute phase and at pre-discharge including the evaluation of NT-proBNP.

Results
At baseline we observed a high prevalence of RV dysfunction as documented by a reduced RV systolic longitudinal function [mean tricuspid annular plane systolic excursion (TAPSE) at admission of 16.47±3.86 mm with 50% of the patients exhibiting a TAPSE&lt;16mm], a decreased DTI-derived tricuspid lateral annular systolic velocity (50% of the subjects showed a tricuspid s' wave&lt;10 cm/s) and a reduced RV fractional area change (mean FAC at admission of 36.4±14.6%). Furthermore, an increased pulmonary arterial systolic pressure (PASP) and a severe impairment in terms of RV coupling to PC was detected at initial evaluation (mean PASP at admission: 38.8±10.8 mmHg; average TAPSE/PASP at admission: 0.45±0.17 mm/mmHg).
At pre-discharge a significant increment of TAPSE (16.47±3.86 mm vs. 17.45±3.88; p=0.05) and a reduction of PASP (38.8±10.8 mmHg vs. 30.5±9.6mmHg, p&lt;0.001) was observed. Furthermore, in the whole population we assisted to a significant improvement in terms of RV function and its coupling with PC as demonstrated by the significant increase of TAPSE/PASP ratio (TAPSE/PASP: 0.45±0.17 mm/mmHg vs 0.62±0.20 mm/mmHg; p&lt;0.001). Patients significantly reduced from admission to discharge the number of B-lines and NT-proBNP (B-lines: 22.2±17.1 vs. 6.5±5 p&lt;0.001; NT-proBNP: 8738±948 ng/l vs 4227±659 ng/l p&lt;0.001) (Figure 1). Nonetheless, no significant changes of left atrial and left ventricular dimensions and function were noted.

Conclusions
In AHF, development of congestion and EVLW significantly impact on the right heart function. Decongestion therapy is effective for restoring acute reversal of RV dysfunction, but the question remains on how to impact on the biological properties of the RV.

Funding Acknowledgement
Type of funding source: None