RT-202
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Theoretical and technological
approach to an electrical painless defibrillator. Preliminary in animal investigation
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Leonardo Cammilli, Gino Grassi*,
Antonio Morra**, Avio Maria Perna***, Francesco Cammilli°, Pietro Liguori°, Francesco
Furlanello°.
Cardiac Surgery "Ulivella" USL 10D, Florence, *Biomedical Equipment
Technol. SNC, Sesto Fiorentino, **R&D Dept. MEDICO S.p.A., Padova, ***Cardiac Surgery
Experimental Laboratory, USL 10D, Florence, °Cardiological and Arrhythmological Dept.,
Santa Chiara Hospital, Trento, Italy
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Abstract
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The problems related at present to the implantable
cardioverter defibrillators are the following ones: 1) loss of patient's consciousness
before and during the electrical shock; 2) very poor and impaired quality of life due to
the loss of consciousness; 3) dramatic and intolerable pain when electrical shock is
delivered to conscious patient; 4) spurious shocks risk due to erroneous ventricular
fibrillation diagnosis; 5) high energy shock.
The aims of our proposal are the following: 1) to prevent the loss of consciousness of
the patients before and during the electrical shock; 2) thus to improve the quality of
life of the patients. In order to obtain these two aims, another one must be reached ie 3)
to abolish or at least to decrease the pain due to the electrical shock: to obtain this
aim neural stimulation of the spinal cord related to the pain topography is proposed,
before the shock is delivered; 4) to prevent spurious shocks and 5) to decrease the energy
of the shock.
Immediate diagnosis of ventricular fibrillation is obtained by means of contemporary
assessment of cardiac cycles rate and lack of ventricular contractility by means of
dedicated sensors.
The sequence of the events should be the following: ventricular fibrillation is
detected into 750 msec: neural stimulation is started; into 1300 msec after ventricular
fibrillation onset, electrical shock is delivered.
Preliminary investigation carried on by the aid of ECC in swine, were performed to
check if ventricular fibrillation is correctly detected into 1 second after its onset and
to check if the shock, delivered after 1300 msec, capable of defibrillating the heart,
needs lower energy than a shock delivered after 10-12 seconds.
Results. Electrically induced ventricular fibrillation as well as
malignant ventricular tachycardia with drop to zero of aortic pressure were always
detected into the first second after the ventricular fibrillation onset. The output of
effective shocks delivered into 1300 msec was lower than the shocks delivered 12 seconds
later.
Because investigations in awake animal are not allowed, in order parameters of
intensity/length of induced pain by the shock - abolished or alleviated by means of the
neural stimulation - could be collected, the basic evaluation of this procedure is
possible only in human trial.
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Key Words
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Implantable cardioverter defibrillator –
function, indications
painless defibrillator, electrical shock, loss of consciousness, pain, quality of life,
inappropriate ICD incidences, OA
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