Naslov
Cardiac Electrotherapy Controlled by Blood Flow Velocity

Autori
Ferek-Petrić, Božidar

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Skup
Advanced Topics in Cardiology

Mjesto i datum
Dubrovnik, Hrvatska, 27.10.2005. - 29.10.2005

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
diastolic function; cardiac pacing; blood flow measurement

Sažetak
If the pacing lead were comprising the blood flow measurement device mounted on its body, the flow velocity measurement would be possible in the vicinity of the lead by means of the special electronic circuits connected to said device. If the flow measurement is done within the tricuspid valve, the waveform reveals the early rapid filling wave and the late atrial filling wave. After detection of the A-wave the implantable electrotherapy device could pace the ventricle synchronously with the atrial filling wave after certain delay. Pacemaker could also detect disappearance of the atrial wave in the case of atrial fibrillation and disappearance of the early filling wave in the case of ventricular arrhythmia. Time interval between the pacing spike and rapid early filling wave, diastolic filling wave duration, diastolic filling wave acceleration, peak filling velocities and diastolic filling fraction are rate responsive pacing sensors. Peak velocities ratio and integral ratio are parameters for ischemia detection. Heart failure my be detected as well. Ultrasonic Doppler is reference method of blood flow measurement. With adequate ultrasonic transducer and appropriately designed electronic circuits, it is possible to incorporate the Doppler ultrasonic measurement system within an implantable therapy device. Special lead conductor is necessary and impedance matching in order to optimize the parameters of the lead conductor transmission line. Electrochemical flow sensor’ s operation doesn’ t consume energy and employs much simpler electronic circuits. Unfortunately, fibrous tissue overgrowth degrades its sensitivity and influences its frequency characteristics. Standard electrode materials such as platinum require small dimensions of an electrode and consequent high input impedance of the sensor’ s measurement amplifier being therefore susceptible to the electromagnetic interference. Sensor capsule comprising integrated preamplifier and highly polarisable electrodes will simplify the design. Nevertheless, sensor calibration problem and its long-term stability will remain as a major problem.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti

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