Table 1.
Studies of the Prevalence of False Tendons (FTs) in the Human Heart by Autopsy (a) and Echocardiography (b).
Table 2.
Statistical Parameters of the Anterior Papillary Muscle (APM) and the Posterior Papillary Muscle (PPM), Calculated from Landmarks in the Left Ventricular (LV) Computer Tomography Scans.
Fig 1.
A computed tomography slice and mesh of the left ventricle (red) with the landmarks (yellow).
This has been used to build the statistic of the papillary muscle: (1) Attachment point (2) Tip of papillary muscle, (3–4) Landmarks for the diameter estimation.
Fig 2.
Different terminations of the false tendon (green) with Purkinje (PK) fibre system (white).
(a) False tendon directly connected to the main PK system, on a left ventricular surface based on triangles with papillary muscle, where the endocardium is red and the epicardium is blue. (b) False tendon terminating in small PK fibre branching, on a left ventricular volume mesh based on tetrahedra with papillary muscle, with myocardium in red.
Fig 3.
The three stages of the Purkinje growing algorithm.
Algorithm applied on the left ventricular surface with papillary muscle. (a) First stage with main fibres in blue and endpoints marked by yellow sphere, (b) finer second stage in green and (c) with final branching of the last stage in red.
Table 3.
Values used for the Deterministic Purkinje Network Growing in the Left Ventricle (LV) [51] and Right Ventricle (RV).
Fig 4.
Example of the myocaridal fibre orientation.
Myocardial fibre orientation generated with the Streeter model in one exemplary heart.
Fig 5.
Shortening of the QRS grouped by decades of shortening.
Shortening given for the direct and delta connected false tendon to various endpoints. The mean QRS duration without FT was 131.9 ± 7.1 ms.
Fig 6.
Comparison of the activation pattern with and without false tendon for the same heart.
(a) The local activation times for the heart without FTs, (b) subtracted the activation time of the heart with a FT to the ventricular free wall, (c) the same with a left bundle branch block and a FT to the anterior papillary muscle.
Table 4.
The mean QRS duration for n = 70 geometries and different configurations of the heart model, and the proportion with QRS duration longer than the threshold Qd,TH = 120 ms.
(LBBB) Left bundle branch block, (PPM) posterior papillary muscle, (APM) the anterior papillary muscle, and (VFW) the ventricular free wall.
Fig 7.
In a few cases the QRS duration may be prolonged by adding a false tendon. In these cases (left without false tendon), the last point activated is still reached by the wave front from the right ventricle, but there is an earlier onset of myocardial activation, here seen in the papillary muscle (right with false tendon).
Fig 8.
Histogram of the QRSd in the study population (n = 70).
(a) Cumulative histogram for all sub groups, (b) Histogram for the healthy, the LBBB, all case with direct connected FT and LBBB and all case with delta connected FT and LBBB. LBBB left bundle branch block, PPM posterior papillary muscle, APM anterior papillary muscle, VFW ventricular free wall, FT false tendon.
Fig 9.
The cumulative percentage of myocardial tissue activated over time.
Activated tissue for the healthy heart, the same heart with left bundle branch block (LBBB), for a heart with a direct connected false tendon (FT) to the ventricular free wall and LBBB. The heart in healthy condition and the case of a LBBB with FT are similar, while in case of a LBBB the slope is smaller.
Fig 10.
Manual division of the myocardium by a plane in left and right ventricle.
This division has been used to estimate the activation time in the different ventricles.
Table 5.
For a healthy heart, the same heart with left bundle branch block (LBBB) and the same heart with direct connected false tendon (FT) to the ventricular free wall and LBBB times are compared.
The time the action potential needs from the activation of the Bundle of His to the first activation in the left ventricle (LV) and right ventricle (RV) are compared, and the time elapsing from the first activation in the LV/RV to the last activation in the LV/RV. This reveals that in case of LBBB the RV and LV are not synchronous in activation, but a FT reinstates part of the synchrony.
Table 6.
Mean and Standard Deviation of the QRSDiff [ms] in the Different Populations.
Fig 11.
QRS Duration as a Function of Left Ventricular Length.
The QRS duration (QRSd) for different sizes of the left ventricle, were a LBBB and a false tendon to the anterior papillary muscle is present. The improvement between the “LBBB, no FT” and “LBBB with FT”-case is given by QRSDiff.
Table 7.
Interquartile Range in [ms] of the QRSd Improvement in each Population and Case.