FIGURES
Figure 1. Apical four-chamber view showing the right atrial global longitudinal strain (RA-GS) with the measurement of reservoir (A), conduit (B) and contractile (C) strain phases.
Figure 2 . A) Specimen showing the internal appearance of the dilated right atrium, the pectinate portion that continues with the appendage is observed to the right of the observer and the anterior leaflet of the tricuspid valve is observed below. B) Transthoracic 3D echocardiogram in four chamber view with mild enlargement of right atrium. C) Mild pulmonary hypertension SPAP of 44 mmHg. D) Histological study (stained with Masson, 10X) of the atrial myocardium of a patient, with mild pulmonary hypertension. The muscle fascicles were mostly cut transversely or obliquely. Two muscle fascicles are replaced by fibrous connective tissue rich in collagen fibers that stain blue, and contrast with the red in which the myocardium is stained. One fascicle is partially replaced by collagen and another almost entirely. The degree of fibrosis in the observed fields was calculated at 25%, since in this image it could reach a little more than a quarter. E) Echocardiography with velocity vector imaging of a patient with low probability of pulmonary hypertension, who had a normal global longitudinal strain of the right atrium (43.5%). Abbreviations : RA-right atrium, RV-right ventricle.
Figure 3. A) Specimen of the heart of a patient with sPAP of 90 mmHg. Heart cut longitudinally from the atria to the ventricles (entry routes through the postero-inferior aspect) that allows to appreciate the dilation of the right cavities. B) Two-dimensional echocardiogram with Doppler in the apical 4-chamber view, with severe tricuspid regurgitation, by means of which an average gradient of 77 mmHg was calculated. C) In the subcostal plane, dilatation of the inferior vena cava (29.1 mm) and collapse of <50% were detected, calculating a right atrial pressure was of 15 mmHg. D) Histological study of the right ventricular myocardium, most of the muscle fibers are in longitudinal section in red and the fibrous tissue rich in collagen fibers is observed blue, it extensively replaces the muscle fascicles, and, in this image, it reaches 75 % or three quarters. The muscle fibers embedded in the fibrous connective tissue appear elongated and thinned. Masson 10x.
E) The global longitudinal strain of the right ventricle, using velocity vector imaging was -14%, in a patient with high probability of PH (sPAP=92 mmHg). Abbreviations: RA-right atrium, RV-right ventricle, LA-left atrium, LV-left ventricle.
Figure 4. Correlation of the absolute values of RV-FWS (A) and RA-GS (B) with logarithmical sPAP. Abbreviations : sPAP: systolic pulmonary artery pressure; RV-FWS: Right ventricular free wall Strain; RA-GS: Right atrial global longitudinal strain.
Figure 5. Differences amongst right atrial reservoir (A), conduit (B) and contractile (C) phases in pulmonary hypertension categories. Abbreviations : sPAP: systolic pulmonary artery pressure; RV-FWS: Right ventricular free wall strain; RA-GS: Right atrial global longitudinal strain.
Figure 6. ROC with the area under the curve of echocardiographic parameters to identify the discrimination capacity for low (A) intermediate/high (B) and high (C) probability of pulmonary hypertension. Abbreviations : ROC= Receiver operator characteristic; Frac-Short= Fractional shortening; TAPSE= Tricuspid annular plane systolic excursion; TEI= TEI index; RV-FWS: Right ventricular free wall strain; RA-GS: Right atrial global longitudinal strain.
Supplementary Figure 1. Algorithm for patients’ selection
Supplementary Figure 2. Correlation of RV-Fibrosis (A) and RA-Fibrosis (B) with sPAP. Abbreviations : sPAP: Systolic pulmonary artery pressure; RV-FWS: Right ventricular free wall strain; RA-GS: Right atrial global longitudinal strain.
Supplementary Figure 3. Correlation of sPAP using echocardiographic and right hearth catheterization (A) and Bland-Altman plot with observed differences between both methods of measured sPAP (B). Abbreviations : sPAP: systolic pulmonary artery pressure.
Table 1: Echocardiography assessment of population of study.Abbreviations : BSA: Body surface area; RVd: Right Ventricle Diameter; FAC: Fractional area change; TAPSE: Tricuspid annular plane systolic excursion; RVS: right ventricular Synchrony.