LEFT-VENTRICULAR VOLUMES ASSESSED BY DIFFERENT NEW 3-DIMENSIONAL ECHOCARDIOGRAPHIC METHODS AND ORDINARY BIPLANE TECHNIQUE

Three-dimensional (3D) echocardiography may overcome the problems with inadequate accuracy and reproducibility of 2D volume measurements of the left ventricle. Aims: To establish the in vitro accuracy and repro ducibility of two new methods for 3D echocardiographic volume determin ation as compared to biplane measurements. Methods: Validation of volu me measurements by a multiplane 3D method was performed on asymmetric latex phantoms (n=8, true volumes 45-304 mi) using rotational acquisit ion of 90 image planes. Porcine agarose-filled asymmetrical left ventr icles (n=7, true volumes 34 - 280 mi) were measured by the same multip lane 3D method based on images acquired by probe rotation axis perpend icular (A) and parallel (B) to the ventricular long axis. Ventricular volumes were also obtained by a simplified 3D system using only the th ree standard apical views (C) and by the ordinary biplane Simpson's me thod (D). Results: On latex phantoms systematic deviation from true vo lumes by multiplane 3D was less than 2%, and 95% variability of indivi dual measurements from this mean was +/- 4,9%. For accuracy on left ve ntricles, systematic bias was small with all the methods (<5%), but 95 % variability of individual measurements was +/-9,0%, 15.4%, 18.8% and 41.3% of true volumes for methods A-D respectively. Corresponding res ults in the same range were obtained for inter-and intraobserver varia bility Conclusion: Individual in vitro volume estimates of left ventri cles are of similar quality using apical multiplane or apical triplane 3D echocardiography. Both methods were superior to the ordinary apica l biplane method, but inferior to multiplane 3D method with the probe directed perpendicular to the ventricular long axis.