Right ventricular basal inflow and outflow tract diameters overestimate right ventricular size in subjects with sigmoid-shaped interventricular septum: a study using three-dimensional echocardiography

Abstract

Purpose: Sigmoid-shaped ventricular septum (SS), a frequently encountered minor abnormality in echocardiographic examinations of the elderly, may have some influence on RV shape. We aimed to determine the influence of SS on the accuracy of the 6 RV linear diameter measurements in the light of three-dimensional echocardiographic (3DE) RV volume. Subjects and Methods: The aorto-septal angle (ASA) was measured in the parasternal long-axis view using two-dimensional echocardiography (2DE) as an index of SS in 70 patients without major cardiac abnormalities who were subdivided into 35 with SS (ASA ≤120 degree) and 35 without SS (NSS). We measured RV end-diastolic volume (RVEDV) using 3DE; in addition, using 2DE, we measured basal RV diameter, mid-cavity diameter, longitudinal diameter and end-diastolic area in the apical four-chamber view; proximal RV outflow tract (RVOT) diameter in the parasternal long-axis view; and proximal and distal RVOT diameters in the parasternal short-axis view. Results: RVEDV did not differ between the SS and NSS groups. The SS group had greater basal RV diameter and proximal and distal RVOT diameters than the NSS group. RV mid-cavity diameter, longitudinal diameter, and end-diastolic area did not differ between the groups. Among the 2DE parameters of RV size, RV end-diastolic area was most strongly correlated with RVEDV (r=0.67), followed by RV mid-cavity diameter (r=0.58). Conclusion: When SS is present, the echocardiographic basal RV diameter and RVOT diameters overestimate RV size, and the measurement of RV end-diastolic area and mid-cavity diameter more correctly reflect 3D RV volume.

Relationship of Aortoseptal Angle with Chronic Hypertension, Clinical and Laboratory Data

“…Since the elongated aorta cannot be expected to curl as much as the small vessels, the point where it will move when it is extended is the partly free starting point, namely the aortic root, and the aortic root enters into the heart, which narrows the angle between the aorta and the septum (Figure 3). Some publications show that the frequency of sigmoid septum increases with age, 2,6) and observations support this information. However, according to our data, it can be suggested that the septum reverting to the sigmoid shape is due to the elongation of the aorta, and this is more related to the duration of HT than the effect of age.…”

“…5) Apart from these articles, AoSA has been mentioned in several studies on septal hypertrophy and the subaortic membrane, asymmetric septal hypertrophy, and subaortic stenosis related to the thickness of the septum and restriction of the subaortic flow. [6][7][8][9][10][11] In addition, in a study published in 2012, it was stated that AoSA was associated with the central blood pressure (BP) and that it changed with antihypertensive treatment. 12) In another study conducted in 2014, AoSA was shown to be correlated with diastolic dysfunction.…”

Right Ventricular Function and Its Coupling With Pulmonary Circulation in Precapillary Pulmonary Hypertension: A Three-Dimensional Echocardiographic Study

“…A 2018 ARIC study of 1,004 elderly participants also showed that a lower RVEF and lower RVEF/PASP ratio are linearly associated with an increased risk of incident heart failure or death, suggesting an important and underrecognized role of RV dysfunction in the progression to heart failure. That study also suggested the potential utility of 3DE for accurate assessment of RV performance (21)(22)(23).…”