P4504Pulmonary circulatory-right ventricular uncoupling in acute decompensated heart failure: a key mediator of congestion

Abstract

Abstract Background The degree of congestion in patients hospitalized for acute decompensated heart failure (ADHF) is estimated using traditional non-invasive markers such as echo-derived inferior vena cava diameter (IVCD) and NT-proBNP levels. The deterioration of right ventricular (RV) function and its uncoupling to pulmonary circulation (Pc) represents a turning point in terms of prognosis and clinical outcome in patients affected by heart failure. However, how RV-to-Pc uncoupling correlates with markers of decompensation and congestion in ADHF patients has never been explored. Purpose To investigate, in a cohort of ADHF patients, the association between the degree of RV-to-Pc uncoupling, assessed by the ratio between tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP), IVCD and right atrial pressure (RAP) estimated at echocardiography. Methods Fourty-six ADHF patients both with reduced and preserved EF (mean age 73.15±10.85 years, 60.8% males) admitted to the Cardiology Department were prospectively enrolled within 24–48 hours from admission. In the acute phase all patients underwent transthoracic echocardiography and laboratory blood tests. Patients were then stratified in tertiles according to TAPSE/PASP ratio (group I: <0.4 mm/mmHg; group II: 0.4 to 0.6 mm/mmHg and group III: >0.6 mm/mmHg) correlating the degree of RV-to-Pc with non-invasive markers of congestion such as NT-proBNP, IVC maximum diameter and RAP. Other echocardiographic parameters including left ventricular (LV) systolic function and LV filling pressures were considered. Results An exponential inverse relationship was found between NT-pro-BNP levels at admission with levels decreasing progressively with the increment of the ratio (Group I: 12828±10600 ng/l; Group II 5549±5383 ng/l; Group III 3695±3870 ng/l; p=0.004) (Figure 1a). An analogous correlation was observed when considering the IVC maximum diameter (Group I: 20.87±5.37 mm; Group II 18.08±4.35 mm; Group III 10.9±3.36 mm; p<0.001) (Figure 1b) and the RAP estimated at echocardiography (Group I: 12.875±5.25 mmHg; Group II 9.157±4.82 mmHg; Group III 4±1.61 mmHg; p<0.001) (Figure 1c). In addition, progressively increasing values of LVEF (Group I: 28±11.3%; Group II 42±17.3%; Group III 49±11.8%; p=0.001) were detected from the lowest to the highest TAPSE/PASP tertiles. No correlation was observed in the three groups for E/E' values at admission (Group I: 17.17±6.7; Group II 19.42±8.36; Group III 15.92±5.7; p=0.5). Figure 1 Conclusions In ADHF, the association between RV to Pc uncoupling, echo-derived measures of congestion and natriuretic peptide levels is here described for the first time. The extent of RV dysfunction in ADHF deserves attention and seems to represent a critical and quite underestimated key mechanism between congestion resolution and in-hospital worsening HF.