intramyocardial การใช้

• Indeed, the intracoronary route is the most straightforward cell delivery route as associated with intramyocardial cellular retention; rentention rates are however low, i . e . exceed 10 %.
• The initial clinical experience led to further animal research using impedance and pacing threshold energy over a range of pulse voltages and pulse widths, using intramyocardial electrodes of 10, 20 & 50 square millimeters surface area.
• For example, in a mouse myocardial infarction model, a single intramyocardial injection of human vascular endothelial growth factor A mRNA ( VEGF-A modRNA ), modified to escape the body's normal defense system, results in long-term improvement of heart function due to mobilization and redirection of epicardial progenitor cells toward cardiovascular cell types.
• Adenoviral TBX18 gene transfer could create biological pacemaker activity in vivo in a large-animal model of complete heart block . Biological pacemaker activity, originating from the intramyocardial injection site, was evident in TBX18-transduced animals starting at day 2 and persisted for the duration of the study ( 14 days ) with minimal backup electronic pacemaker use.
• These characteristics were incorporated in the next design to be implanted in humans, the model P4, which employed 30 mm 2 area intramyocardial electrodes ( and later transvenous pacing electrodes ), a very conservative 7.5 volt pulse and for further conservatism a magnetically operated switch which could be actuated from outside the body to change the pulse width from 0.5 to 1.0 millisecond.
• Using pioneering positron emission tomography technqiues at the MRC Cyclotron Center at Hammersmith Hospital, London along with Prof J . S . Kooner, Dr Stuart Rosen and Prof Paulo Camici, he demonstrated that angina occurring after a meal is due to " intramyocardial steal ", wherein blood is redistributed from ischemic areas of the myocardium to the normally supplied myocardial in order to maintain overall myocardial blood flow.