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Coronary-aortic interaction during ventricular isovolumic contraction.

van Houwelingen MJ, Merkus D, Te Lintel Hekkert M, van Dijk G, Hoeks AP, Duncker DJ - Med Biol Eng Comput (2011)

Bottom Line: A similar procedure was used to occlude only the right coronary artery (RCA) and finally all three main coronary arteries simultaneously.None of the occlusion protocols caused a decrease in the arterial pressure perturbation in the aorta during occlusion (P > 0.20) nor an increase during reactive hyperemia (P > 0.22), despite a higher deceleration of coronary blood volume flow (P = 0.03) or increased coronary conductance (P = 0.04) during hyperemia.These results show that the pre-systolic aortic pressure perturbation does not originate from the coronary arteries.

View Article: PubMed Central - PubMed

Affiliation: Experimental Cardiology, Thoraxcenter, Cardiovascular Research Institute COEUR, Erasmus MC, University Medical Center Rotterdam, Dr Molewaterplein 50, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands. m.vanhouwelingen@erasmusmc.nl

ABSTRACT
In earlier work, we suggested that the start of the isovolumic contraction period could be detected in arterial pressure waveforms as the start of a temporary pre-systolic pressure perturbation (AIC(start), start of the Arterially detected Isovolumic Contraction), and proposed the retrograde coronary blood volume flow in combination with a backwards traveling pressure wave as its most likely origin. In this study, we tested this hypothesis by means of a coronary artery occlusion protocol. In six Yorkshire × Landrace swine, we simultaneously occluded the left anterior descending (LAD) and left circumflex (LCx) artery for 5 s followed by a 20-s reperfusion period and repeated this sequence at least two more times. A similar procedure was used to occlude only the right coronary artery (RCA) and finally all three main coronary arteries simultaneously. None of the occlusion protocols caused a decrease in the arterial pressure perturbation in the aorta during occlusion (P > 0.20) nor an increase during reactive hyperemia (P > 0.22), despite a higher deceleration of coronary blood volume flow (P = 0.03) or increased coronary conductance (P = 0.04) during hyperemia. These results show that the pre-systolic aortic pressure perturbation does not originate from the coronary arteries.

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Pressure perturbation area (PPA) at baseline (BL) and hyperemia (H). Shown are individual animals (open symbols) and mean ± SD (solid circles)
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Fig4: Pressure perturbation area (PPA) at baseline (BL) and hyperemia (H). Shown are individual animals (open symbols) and mean ± SD (solid circles)

Mentions: Coronary vasodilatation and reactive hyperemia occurred in the LAD and RCA after release of coronary artery occlusion (Table 1). Compared to baseline values, mean CBF in the LAD and RCA increased by 79 ± 27% and 72 ± 19%, respectively. The steepness of the early systolic blood volume flow slope in both LAD and RCA increased (i.e. the slope became more negative) under influence of reactive hyperemia, although it reached levels of statistical significance only following LAD + LCx occlusion (P = 0.03, Table 1). PPA was not enhanced by reactive hyperemia following any of the occlusion combinations (all P > 0.22, Fig. 4).Fig. 4


Coronary-aortic interaction during ventricular isovolumic contraction.

van Houwelingen MJ, Merkus D, Te Lintel Hekkert M, van Dijk G, Hoeks AP, Duncker DJ - Med Biol Eng Comput (2011)

Pressure perturbation area (PPA) at baseline (BL) and hyperemia (H). Shown are individual animals (open symbols) and mean ± SD (solid circles)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3139876&req=5

Fig4: Pressure perturbation area (PPA) at baseline (BL) and hyperemia (H). Shown are individual animals (open symbols) and mean ± SD (solid circles)
Mentions: Coronary vasodilatation and reactive hyperemia occurred in the LAD and RCA after release of coronary artery occlusion (Table 1). Compared to baseline values, mean CBF in the LAD and RCA increased by 79 ± 27% and 72 ± 19%, respectively. The steepness of the early systolic blood volume flow slope in both LAD and RCA increased (i.e. the slope became more negative) under influence of reactive hyperemia, although it reached levels of statistical significance only following LAD + LCx occlusion (P = 0.03, Table 1). PPA was not enhanced by reactive hyperemia following any of the occlusion combinations (all P > 0.22, Fig. 4).Fig. 4

Bottom Line: A similar procedure was used to occlude only the right coronary artery (RCA) and finally all three main coronary arteries simultaneously.None of the occlusion protocols caused a decrease in the arterial pressure perturbation in the aorta during occlusion (P > 0.20) nor an increase during reactive hyperemia (P > 0.22), despite a higher deceleration of coronary blood volume flow (P = 0.03) or increased coronary conductance (P = 0.04) during hyperemia.These results show that the pre-systolic aortic pressure perturbation does not originate from the coronary arteries.

View Article: PubMed Central - PubMed

Affiliation: Experimental Cardiology, Thoraxcenter, Cardiovascular Research Institute COEUR, Erasmus MC, University Medical Center Rotterdam, Dr Molewaterplein 50, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands. m.vanhouwelingen@erasmusmc.nl

ABSTRACT
In earlier work, we suggested that the start of the isovolumic contraction period could be detected in arterial pressure waveforms as the start of a temporary pre-systolic pressure perturbation (AIC(start), start of the Arterially detected Isovolumic Contraction), and proposed the retrograde coronary blood volume flow in combination with a backwards traveling pressure wave as its most likely origin. In this study, we tested this hypothesis by means of a coronary artery occlusion protocol. In six Yorkshire × Landrace swine, we simultaneously occluded the left anterior descending (LAD) and left circumflex (LCx) artery for 5 s followed by a 20-s reperfusion period and repeated this sequence at least two more times. A similar procedure was used to occlude only the right coronary artery (RCA) and finally all three main coronary arteries simultaneously. None of the occlusion protocols caused a decrease in the arterial pressure perturbation in the aorta during occlusion (P > 0.20) nor an increase during reactive hyperemia (P > 0.22), despite a higher deceleration of coronary blood volume flow (P = 0.03) or increased coronary conductance (P = 0.04) during hyperemia. These results show that the pre-systolic aortic pressure perturbation does not originate from the coronary arteries.

Show MeSH
Related in: MedlinePlus