Comparison of left and right ventricular volume measurement using the Simpson's method and the area length method

Abstract

Purpose: To compare ventricular volume measurement using a volumetric approach in the three standard cardiac planes and ventricular volume estimation by a geometrical model, the Area-Length method (ALM).

Materials and methods: Fifty-six healthy volunteers were examined (27 males, 29 females) on a 1.5T MR-unit with ECG-triggered steady state free precision (SSFP) Cine-MR sequences and parallel image acquisition. Multiple slices in standardized planes including the short-axis view (sa), 4-chamber view (4ch), left and right 2-chamber views (2ch) were used to cover the whole heart. End-systolic and end-diastolic ventricular volumes (EDV, ESV), stroke volume (SV), and ejection fraction (EF) were calculated with Simpson's rule in all planes and with ALM in the 2ch and 4ch planes. Global function parameters measured in the sa plane were compared with those obtained in the other imaging planes.

Results: A very good correlation is observed when comparing functional parameters calculated with Simpson's rule in all imaging planes: for instance, the mean EDV/ESV of the left and right ventricle of the female population group measured in sa, 4ch, and 2ch: left ventricle EDV/ESV 114.3/44.4, 120.9/46.5, and 117.7/45.3 ml; right ventricle EDV/ESV 106.6/46.0, 101.2/41.1, and 103.5/43.0 ml. Functional parameters of the left ventricle calculated with ALM in 2ch and 4ch correlate to parameters obtained in sa with Simpson's rule in the range of 5-10%: for instance, the EDV/ESV of the left ventricle of the male population group measured in the sa, 4ch, and 2ch: 160.3/63.5, 163.1/59.0, and 167.0/65.7 ml. Functional parameters of the right ventricle measured with ALM in 4ch are 40-50% lower and calculated in 2ch almost double as high as compared with the parameters obtained in sa with Simpson's rule: for instance, male right ventricular EDV/ESV measured in sa, 4ch, and 2ch: 153.4/68.1, 97.5/34.5, and 280.2/123.2 ml. The EF correlates for all imaging planes measured with the Simpson's rule in both ventricles and using ALM in the left ventricle except for males with an overestimation of less than 6%. The EF of the right ventricle is calculated higher using ALM in 4ch and 2ch compared to the EF calculated in sa: female/male EF of the right ventricle measured in the sa, 4ch, and 2ch: 56.8/55.7, 66.0/65.0, and 60.0/57.0%.

Conclusion: In the setting of healthy volunteers the ALM method should not be used in 2ch and 4ch planes of the right ventricle because of lacking correlation of global functional parameters compared to those obtained in the sa plane. Using Simpson's rule functional parameters correlate well to each other in the different imaging planes.