TY - JOUR
T1 - Initiation of ventricular contraction as reflected in the aortic pressure waveform
AU - van Houwelingen, Marc J.
AU - Merkus, Daphne
AU - Hekkert, Maaike Te Lintel
AU - van Dijk, Geert
AU - Hoeks, Arnold P. G.
AU - Duncker, Dirk J.
PY - 2012/4
Y1 - 2012/4
N2 - Prior to aortic valve opening, aortic pressure is perturbed by ventricular contraction. The onset of this pressure perturbation coincides with the onset of the left ventricular (LV) isovolumic contraction, and hence will be referred to as the start of the arterially detected isovolumic contraction (AIC(start)). In the present study we test the hypothesis that the pressure perturbation indeed has a cardiac origin. In ten Yorkshire-Landrace swine, waveform intensity analysis demonstrated that AIC(start) was followed by a positive intensity wave (0.3 x 10(5) +/- 0.3 x 10(5) W (m(2) s(2))(-1)). Timing analysis of LV and aortic pressure waveform showed that AIC(start) was preceded by a LV pressure perturbation (3.8 +/- 1.8 ms, p <0.001). These novel cardiac timing and aortic wave intensity findings reveal the cardiac origin of the pressure perturbation. In 15 Yorkshire-Landrace swine, myocardial motion analysis showed a significantly higher rate of segment shortening during the first part of the LV pressure perturbation. Therefore, both the LV and aortic pressure perturbation are most likely caused by the early phase of myocardial contraction, which also causes mitral valve closure. Consequently, AIC(start) is useful in the determination of the isovolumic contraction period, a well-known marker to quantify cardiac dysfunction.
AB - Prior to aortic valve opening, aortic pressure is perturbed by ventricular contraction. The onset of this pressure perturbation coincides with the onset of the left ventricular (LV) isovolumic contraction, and hence will be referred to as the start of the arterially detected isovolumic contraction (AIC(start)). In the present study we test the hypothesis that the pressure perturbation indeed has a cardiac origin. In ten Yorkshire-Landrace swine, waveform intensity analysis demonstrated that AIC(start) was followed by a positive intensity wave (0.3 x 10(5) +/- 0.3 x 10(5) W (m(2) s(2))(-1)). Timing analysis of LV and aortic pressure waveform showed that AIC(start) was preceded by a LV pressure perturbation (3.8 +/- 1.8 ms, p <0.001). These novel cardiac timing and aortic wave intensity findings reveal the cardiac origin of the pressure perturbation. In 15 Yorkshire-Landrace swine, myocardial motion analysis showed a significantly higher rate of segment shortening during the first part of the LV pressure perturbation. Therefore, both the LV and aortic pressure perturbation are most likely caused by the early phase of myocardial contraction, which also causes mitral valve closure. Consequently, AIC(start) is useful in the determination of the isovolumic contraction period, a well-known marker to quantify cardiac dysfunction.
KW - isovolumic contraction
KW - ventricular aortic interaction
KW - timing analysis
KW - pulse wave analysis
U2 - 10.1088/0967-3334/33/4/557
DO - 10.1088/0967-3334/33/4/557
M3 - Article
C2 - 22415053
SN - 0967-3334
VL - 33
SP - 557
EP - 569
JO - Physiological Measurement
JF - Physiological Measurement
IS - 4
ER -