From the Research
In an apical 4-chamber view, when the right ventricle (RV) apex wraps around the left ventricle (LV), this suggests right ventricular enlargement or dilation, which is associated with increased all-cause mortality in hypertrophic cardiomyopathy, as shown in a study published in the Mayo Clinic proceedings in 2022 1. This finding is abnormal and indicates potential right-sided heart pathology. Normal cardiac anatomy shows the RV appearing triangular in shape and not extending beyond the LV apex. When RV dilation occurs, the chamber enlarges and the apex extends further, causing it to wrap around or appear to "hug" the LV apex.
The wrapping appearance occurs because the enlarged RV pushes against the interventricular septum and extends beyond its normal anatomical boundaries. This finding may indicate conditions such as pulmonary hypertension, right ventricular volume overload (as seen in atrial septal defects or tricuspid regurgitation), right ventricular pressure overload (as in pulmonary stenosis), arrhythmogenic right ventricular cardiomyopathy, or right heart failure.
To evaluate RV size and function, it is recommended to use the RV-focused view, as it provides more reproducible measurements compared to the 4Ch view, as demonstrated in a study published in the Journal of the American Society of Echocardiography in 2019 2. The RV-focused view allows for more accurate assessment of RV dimensions, function, and tricuspid valve function, which are essential for determining the underlying cause of RV dilation.
Further evaluation should include measurement of RV dimensions, assessment of RV function, evaluation of tricuspid valve function, and estimation of pulmonary artery pressures to determine the underlying cause. Additionally, three-dimensional imaging can be used to derive standardized RV focused views, which have been shown to strongly relate to CMR-derived measures and may improve reproducibility in RV 2D measurements, as demonstrated in a study published in The international journal of cardiovascular imaging in 2018 3.
It is essential to note that RV failure is a major determinant of functional state and prognosis in pulmonary arterial hypertension, and maladaptive RVH is characterized by increased N-terminal pro-brain natriuretic peptide levels, troponin release, elevated catecholamine levels, RV dilatation, and late gadolinium enhancement on MRI, as discussed in a study published in Circulation research in 2014 4.
In summary, the finding of the RV apex wrapping around the LV in an apical 4-chamber view suggests right ventricular enlargement or dilation, which requires further evaluation to determine the underlying cause and guide management. The use of RV-focused views and three-dimensional imaging can provide more accurate and reproducible measurements of RV size and function, which are essential for determining the underlying cause of RV dilation and guiding management 2, 3.