Biomedical Engineering Reference
In-Depth Information
4.2 Limitations
The use of a coarse grid for evaluating pacing locations was a computational
necessity. The smooth transitions in each metric seen in Fig.
2
mean that it is
unlikely that the gross morphology of the metric maps will change but the size of
the optimal regions may be altered.
The model evaluated here provides a preliminary application of multiphysics
computational models to a clinically relevant application. The model requires
significant amounts of high quality consistent data to constrain the model
parameters. This has limited the number of patient's hearts that can be modeled.
To confirm these results, models of multiple patients' hearts are required and these
results must then be confirmed in clinical studies.
The model only evaluated a subset of potential metrics of cardiac function and
this list could readily be extended. The QRS duration and peak stretch could both be
measured in the clinic, although they have not been used as measures for optimizing
CRT lead position. The proposed measures of global mechanical cardiac function
only looked to achieve a maximum or minimum value and future work could
explore the goal of achieving a more homogenous spatial or temporal distribution.
5 Conclusion
Computer modeling predicts that the maximum rate of pressure development in the
LV provides a general representation of multiple changes in cardiac function
following CRT. The model supports the use of the maximum rate of pressure
development for identifying optimal lead locations during CRT implantation.
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