TY - JOUR
T1 - Acute and chronic ventricular-arterial coupling in systole and diastole
T2 - Insights from an elderly hypertensive model
AU - Shapiro, Brian P.
AU - Lam, Carolyn S.P.
AU - Patel, Jeetendra B.
AU - Mohammed, Selma F.
AU - Kruger, Martina
AU - Meyer, Donna M.
AU - Linke, Wolfgang A.
AU - Redfield, Margaret M.
PY - 2007/9
Y1 - 2007/9
N2 - Aging and hypertension lead to arterial remodeling and tandem increases in arterial (Ea) and ventricular (LV) systolic stiffness (ventricular-arterial [VA] coupling). Age and hypertension also predispose to heart failure with normal ejection fraction (HFnlEF), where symptoms during hypertensive urgencies or exercise are common. We hypothesized that: (1) chronic VA coupling also occurs in diastole, (2) acute changes in Ea are coupled with shifts in the diastolic and systolic pressure-volume relationships (PVR), and (3) diastolic VA coupling reflects changes in LV diastolic stiffness rather than external forces or relaxation. Old chronically hypertensive (OHT, n=8) and young normal (YNL, n=7) dogs underwent assessment of PVR (caval occlusion) and of aortic pressure, dimension, and flow, at baseline and during changes in afterload and preload. Concomitant changes in the slope/position of PVR were accounted for by calculating systolic (ESV200) and diastolic (EDV20) volumes at common pressures (capacitance). OHT displayed marked vascular remodeling. Indices reflecting the pulsatile component of Ea (aortic stiffness and systemic arterial compliance) were more impaired in OHT at any distending pressure. In both groups, acute increases in Ea were associated with decreases in ESV200 and EDV20. However, at any load, OHT had lower ESV200 and EDV20, associated with LV remodeling and myocardial endothelin activation. Acute changes in EDV20 were not mediated by changes in relaxation or external forces. These observations provide insight into the mechanisms whereby arterial remodeling and acute and chronic VA coupling in both systole and diastole may predispose to and interact with increases in load to cause HFnlEF.
AB - Aging and hypertension lead to arterial remodeling and tandem increases in arterial (Ea) and ventricular (LV) systolic stiffness (ventricular-arterial [VA] coupling). Age and hypertension also predispose to heart failure with normal ejection fraction (HFnlEF), where symptoms during hypertensive urgencies or exercise are common. We hypothesized that: (1) chronic VA coupling also occurs in diastole, (2) acute changes in Ea are coupled with shifts in the diastolic and systolic pressure-volume relationships (PVR), and (3) diastolic VA coupling reflects changes in LV diastolic stiffness rather than external forces or relaxation. Old chronically hypertensive (OHT, n=8) and young normal (YNL, n=7) dogs underwent assessment of PVR (caval occlusion) and of aortic pressure, dimension, and flow, at baseline and during changes in afterload and preload. Concomitant changes in the slope/position of PVR were accounted for by calculating systolic (ESV200) and diastolic (EDV20) volumes at common pressures (capacitance). OHT displayed marked vascular remodeling. Indices reflecting the pulsatile component of Ea (aortic stiffness and systemic arterial compliance) were more impaired in OHT at any distending pressure. In both groups, acute increases in Ea were associated with decreases in ESV200 and EDV20. However, at any load, OHT had lower ESV200 and EDV20, associated with LV remodeling and myocardial endothelin activation. Acute changes in EDV20 were not mediated by changes in relaxation or external forces. These observations provide insight into the mechanisms whereby arterial remodeling and acute and chronic VA coupling in both systole and diastole may predispose to and interact with increases in load to cause HFnlEF.
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U2 - 10.1161/HYPERTENSIONAHA.107.090092
DO - 10.1161/HYPERTENSIONAHA.107.090092
M3 - Article
C2 - 17620524
AN - SCOPUS:34548185475
VL - 50
SP - 503
EP - 511
JO - Hypertension
JF - Hypertension
SN - 0194-911X
IS - 3
ER -