Dynamic trend of lung fluid movement during exercise in heart failure: From lung imaging to alveolar-capillary membrane function.

BACKGROUND: In chronic heart failure (HF), exercise-induced increase in pulmonary capillary pressure may cause an increase of pulmonary congestion, or the development of pulmonary oedema. We sought to assess in HF patients the exercise-induced intra-thoracic fluid movements, by measuring plasma brain natriuretic peptide (BNP), lung comets and lung diffusion for carbon monoxide (DLCO) and nitric oxide (DLNO), as markers of hemodynamic load changes, interstitial space and alveolar-capillary membrane fluids, respectively. METHODS AND RESULTS: Twenty-four reduced ejection fraction HF patients underwent BNP, lung comets and DLCO/DLNO measurements before, at peak and 1 h after the end of a maximal cardiopulmonary exercise test. BNP significantly increased at peak from 549 (328-841) to 691 (382-1207, p < 0.0001) pg/mL and almost completely returned to baseline value 1 h after exercise. Comets number increased at peak from 9.4 ± 8.2 to 24.3 ± 16.7, returning to baseline (9.7 ± 7.4) after 1 h (p < 0.0001). DLCO did not change significantly at peak (from 18.01 ± 4.72 to 18.22 ± 4.73 mL/min/mmHg), but was significantly reduced at 1 h (16.97 ± 4.26 mL/min/mmHg) compared to both baseline (p = 0.0211) and peak (p = 0.0174). DLNO showed a not significant trend toward lower values 1 h post-exercise. CONCLUSIONS: Moderate/severe HF patients have a 2-step intra-thoracic fluid movement with exercise: the first during active exercise, from the vascular space toward the interstitial space, as confirmed by comets increase, without any effect on diffusion, and the second, during recovery, toward the alveolar-capillary membrane, clearing the interstitial space but worsening gas diffusion.

Multi-parametric "on board" evaluation of right ventricular function using three-dimensional echocardiography: feasibility and comparison to traditional two-and three dimensional echocardiographic measurements.

Three-dimensional echocardiographic (3DE) of right ventricle (RV) has been validated in many clinical settings. However, the necessity of complicated and off-line dedicated software has reduced its diffusion. A new simplified "on board" 3DE software (OB) has been developed to obtain RV volumes and ejection fraction (EF) together with several conventional parameters automatically derived from 3DE: tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), longitudinal strain (LS). Aims of this study were to evaluate feasibility and accuracy of OB RV analysis. A complete 2DE and 3DE with OB 3DRV evaluation was obtained in 35 normal subjects and 105 patients with different pathologies. Results were compared with the conventional off-line software (OFL) and with the 2D-derived corresponding values. A subgroup of 22 patients underwent also cardiac CMR. OB 3DRV was feasible in 133/140 cases (95%) in a mean time of 97.5 ± 33 s lower than OFL analysis (129 ± 52 s plus dataset loading 80 ± 24 s). Imaging quality was good in 84%. OB and OFL 3DE RV volumes and EF were similar. 3DE derived FSA and LS (but not TAPSE) were similar to 2DE values and correlated with tissue Doppler systolic peak velocity, dP/dt, systolic pulmonary pressure and myocardial performance index. OB RV volumes and EF well correlated with CMR. (bias + SD: - 21.5 ± 20 mL for EDV; - 8.2 ± 12.4 mL for ESV; - 1 ± 5.9% for EF). OB 3DE method is feasible, simple, time saving. It easily provides 3DE RV volumes and multiple functional parameters. Off-line operator border adjustment may improve accuracy of 3DE TAPSE.