Andrea Colella, Giuseppe
Vaccari*, Enrico Dovellini*, Gian Carlo Calamai*, Gianni Plicchi**, Massimo Bonacchi*,
Marino Vaccari*, Antonio Michelucci, Maria Cristina Porciani, Luigi Padeletti, Gian Franco
Gensini.
Dept. of Internal Medicine and Cardiology, University of Florence, Dept. of Cardiology and
Cardiac Surgery, Florence, Dept. of Engineering, University of Bologna, Italy
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Background. An implantable
acceleration sensor (BEST-Living, Sorin, Italy) located inside the stimulating tip of a
standard unipolar pacing lead recently developed and implanted in patients. Peak
endocardial acceleration (PEA) of the first heart sound (FHS) vibrations can be
consistently and safety obtained with this lead inserted in the apex of the right
ventricle. Previous investigations have shown that in non ischemic hearts the PEA changes
mainly reflect the left ventricular contractile function. This has been experimentally
assessed in acute RV pressure overload with inadequate LV filling wich showed PEA to
follow directional change mainly reflect the left ventricular contractile function. This
has been experimentally assessed in acute RV pressure overload with inadequate LV filling
which showed PEA to follow directional changes in LV dP/dt max and in RV dP/dt max
demonstrating a dominance of LV contractility in modulating PEA values.
Aim of the Study. To acutely determine the correlation PEA-LV dP/dt
max in pigs during temporary occlusion of the middle portion of the left anterior
descending coronary artery.
Methods. Under general anesthesia intubated pigs have been
instrumented for the RV assessment of PEA, aortic/LV pressure and external/epicardial EKG
during 13 temporary (5 min) occlusion of the middle portion of the left anterior
descending coronary artery.
Results. Data processing, including 3 min of basal time, the
occlusion time (5 min) and 3 min of recovery time, showed a good correlation index PEA-LV
dP/dt max: R = 0.74 ± 0.14.
Conclusions. The preliminary data demonstrate a very good correlation
index (R) PEA-LV dP/dt max in pigs during acute coronary occlusion enabling PEA to be used
for monitoring heart contractility changes in ischemic heart diseases.
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