Interaction between the septum and the left (right) ventricular free wall in order to evaluate the effects on coronary blood flow: numerical simulation

Abstract

Mathematical modelling of the cardiovascular system (CVS) can help in understanding the complex interactions between both the ventricles and the septum. By describing the behaviour of the left (right) ventricular free wall, atria and septum using the variable elastance models, it is possible to reproduce their interactions. By relating the mechanical properties of both atria and both ventricles to the electrocardiogram (ECG) signal, it is possible to analyse the effects produced by different ECG delay on haemodynamic parameters. In the cardiovascular field, the incorrect interactions between septum and both ventricular free walls are based on many pathological conditions, i.e. symptomatic heart failure resulting from systolic dysfunction, ischemic dilated cardiomyopathy, and so on. The possible corrections that can be induced on the QRS complex duration in the ECG signal (i.e. cardiac resynchronisation therapy, CRT) can produce benefits improving the clinical status of the patient. The aim of this work was to evaluate, using our numerical simulator of the CVS, the effects induced on coronary blood flow (CBF) and aortic pressure using different ECG times, intra-ventricular and inter-ventricular delays. The results were obtained by reproducing the circulatory baseline and CRT conditions of seven patients described in literature. Haemodynamic simulated results are in accordance with literature data. Also the controversial results on CBF, in presence of CRT, are consistent with those described in the literature.

How can LVAD support influence ventricular energetics parameters in advanced heart failure patients? A retrospective study

“…Our efforts mainly focused on the hemodynamic parameters derived from echocardiographic assessment and right heart catheter [4][5][6]. CARDIOSIM © is the numerical simulator of the cardiovascular system used for the study [7][8][9][10][11][12][13][14][15]. This software is based on 0-D mathematical models, which reproduce the ventricular, atrial and septal behavior according to a modified time-varying elastance concept [4,7,8].…”

“…CARDIOSIM © is the numerical simulator of the cardiovascular system used for the study [7][8][9][10][11][12][13][14][15]. This software is based on 0-D mathematical models, which reproduce the ventricular, atrial and septal behavior according to a modified time-varying elastance concept [4,7,8]. The library of the simulator allows the assembly of specific modules describing different circulatory districts [8][9][10][11][12][13][14][15].…”

Decision-making in advanced heart failure patients requiring LVAD insertion: Can preoperative simulation become the way forward? A case study

“…[4] Mathematical representation of the cardiovascular system based on pressure-volume (PV) relationship and lumped parameter models can help simulate a wide range of cardiovascular conditions and therapeutic interventions maintaining the ability to run on any personal computer. [5] Their simplicity and versatility makes them suitable for clinical assessment on a daily basis, [6][7][8][9][10][11] although the successful application of this method requires specific haemodynamics teaching addressed to clinicians. [10][11][12] The treatment of advanced heart failure may benefit from a modelling framework to guide device treatment and predict outcome.…”

“…[5] Their simplicity and versatility makes them suitable for clinical assessment on a daily basis, [6][7][8][9][10][11] although the successful application of this method requires specific haemodynamics teaching addressed to clinicians. [10][11][12] The treatment of advanced heart failure may benefit from a modelling framework to guide device treatment and predict outcome. The role of a mechanical circulatory support system (MCSS) as a long-term solution is increasing in view of the evolving technology and worsening heart failure patient population.…”

Cardiac Energetics in Presence of Lung Assist Devices: <i>In Silico</i> Study

“…In our development, we put much emphasis to These (software) modules are based on mathematical models which describe the behavior of the ventricles, the atria and the septa. They are mainly based on a variable elastance modeling approach; however, we assumed that the atrial septa are rigid [12] [14].…”