Dataset Information

Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure.

ABSTRACT: Apelin plays important roles in cardiovascular homeostasis. However, its effects on the mechanoenergetics of heart failure (HF) are unavailable. We attempted to investigate the effects of apelin on the left ventricular-arterial coupling (VAC) and mechanical efficiency in rats with HF. HF was induced in rats by the ligation of the left coronary artery. The ischemic HF rats were treated with apelin or saline for 12 weeks. The sham-operated animals served as the control. The left ventricular (LV) afterload and the systolic and diastolic functions, as well as the mechanoenergetic indices were estimated from the pressure-volume loops. Myocardial fibrosis by Masson's trichrome staining, myocardial apoptosis by TUNEL, and collagen content in the aorta as well as media area in the aorta and the mesenteric arteries were determined. Our data indicated that HF rats manifested an increased arterial load (Ea), a declined systolic function (reduced ejection fraction, +dP/dtmax, end-systolic elastance, and stroke work), an abnormal diastolic function (elevated end-diastolic pressure, ?, and declined -dP/dtmax), and decreased mechanical efficiency. Apelin treatment improved those indices. Concomitantly, increased fibrosis in the LV myocardium and the aorta and enhanced apoptosis in the LV were partially restored by apelin treatment. A declined wall-to-lumen ratio in the mesenteric arteries of the untreated HF rats was further reduced in the apelin-treated group. We concluded that the rats with ischemic HF were characterized by deteriorated LV mechanoenergetics. Apelin improved mechanical efficiency, at least in part, due to the inhibiting cardiac fibrosis and apoptosis in the LV myocardium, reducing collagen deposition in the aorta and dilating the resistant artery.

SUBMITTER: Ouyang Q

PROVIDER: S-EPMC6604493 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure.

Ouyang Qiufang Q You Tao T Guo Jinjian J Xu Rong R Guo Quehui Q Lin Jiqin J Zhao Hongjia H

Disease markers 20190617

Apelin plays important roles in cardiovascular homeostasis. However, its effects on the mechanoenergetics of heart failure (HF) are unavailable. We attempted to investigate the effects of apelin on the left ventricular-arterial coupling (VAC) and mechanical efficiency in rats with HF. HF was induced in rats by the ligation of the left coronary artery. The ischemic HF rats were treated with apelin or saline for 12 weeks. The sham-operated animals served as the control. The left ventricular (LV) a ...[more]

PMID: 31316680

Similar Datasets

Project description:BACKGROUND:Weaning post-cardiac surgery patients from mechanical ventilation (MV) poses a big challenge to these patients. Optimized left ventricular-arterial coupling (VAC) may be crucial for reducing the MV duration of these patients. However, there is no research exploring the relationship between VAC and the duration of MV. We performed this study to investigate the relationship between left ventricular-arterial coupling (VAC) and prolonged mechanical ventilation (MV) in severe post-cardiac surgery patients. METHODS:This was a single-center retrospective study of 56 severe post-cardiac surgery patients from January 2015 to December 2017 at the Department of Critical Care Medicine of Peking Union Medical College Hospital. Patients were divided into two groups according to the duration of MV (PMV group: prolonged mechanical ventilation group, MV >?6?days; Non-PMV group: non-prolonged mechanical ventilation group, MV???6?days). Hemodynamics and tissue perfusion data were collected or calculated at admission (T0) and 48?h after admission (T1) to the ICU. RESULTS:In terms of hemodynamic and tissue perfusion data, there were no differences between the two groups at admission (T0). Compared with the non-prolonged MV group after 48?h in the ICU (T1), the prolonged MV group had significantly higher values for heart rate (108?±?13 vs 97?±?12, P?=?0.018), lactate (2.42?±?1.24 vs.1.46?±?0.58, P?<?0.001), and Ea/Ees (5.93?±?1.81 vs. 4.05?±?1.20, P?<?0.001). Increased Ea/Ees (odds ratio, 7.305; 95% CI, 1.181-45.168; P?=?0.032) and lactate at T1 (odds ratio, 17.796; 95% CI, 1.377-229.988; P?=?0.027) were independently associated with prolonged MV. There was a significant relationship between Ea/EesT1 and the duration of MV (r?=?0.512, P?<?0.01). The area under the receiver operating characteristic (AUC) of the left VAC for predicting prolonged MV was 0.801, and the cutoff value for Ea/Ees was 5.12, with 65.0% sensitivity and 90.0% specificity. CONCLUSIONS:Left ventricular-arterial coupling was associated with prolonged mechanical ventilation in severe post-cardiac surgery patients. The assessment and optimization of left VAC might be helpful in reducing duration of MV in these patients.

Project description:Left ventricular ejection fraction (LVEF) and ventricular-arterial coupling (VAC) [VAC = Ea/Ees; Ea: effective arterial elastance; Ees: left ventricle (LV) elastance] are both dimensionless ratios with important limitations, especially in heart failure setting. The LVEF to VAC relationship is a divergent non-linear function, having a point of intersection at the specific value of 0.62, where V0 = 0 ml (V0: the theoretical extrapolated value of the volume-axis intercept at end-systolic pressure 0 mmHg). For the dilated LV, both LVEF and VAC are highly dependent on V0 which is inconclusive when derived from single-beat Ees formulas. VAC simplification should be avoided. Revisiting the relationship between systolic time intervals (STI), pressure, and volumes could provide simple-to-use guiding formulas, affordable for daily clinical practice. We have analyzed by echocardiography the hemodynamics of 21 patients with severe symptomatic heart failure with reduced ejection (HFrEF) compared to 12 asymptomatic patients (at risk of heart failure with mild structural disease). The groups were unequivocally separated by 'classic' measures (LVEF, LV end-systolic volume (ESV), LV mass, STI). Chen's Ees formula was weakly correlated with LVEF and indexed ESV (ESVi) but better correlated to the pre-ejection period (PEP); PEP/total ejection time (PEP/TET); systolic blood pressure/PEP (SBP/PEP) (P < 0.001). Combining the predictability of the LVEF to the determinant role of SBP/PEP on the Ees variations, we obtained: (SBP*LVEF)/PEP mm Hg/ms, with an improved R 2 value (R 2 = 0.848; P < 0.001). The strongest correlations to VAC were for LVEF (R = -0.849; R 2 = 0.722) and PEP/TET (R = 0.925; R 2 = 0.857). By multiple regression, the VAC was strongly predicted (N = 33): (R = 0.975; R 2 = 0.95): VAC = 0.553-0.009*LVEF + 3.463*PEP/TET, and natural logarithm: Ln (VAC) = 0.147-1.4563*DBP/SBP*0.9-0.010*LVEF + 4.207*PEP/TET (R = 0.987; R 2 = 0.975; P = 0) demonstrating its exclusive determinants: LVEF, PEP/TET, and DBP/SBP. Considering Ea as a known value, the VAC-derived Ees formula: Ees_d ≈ Ea/(0.553-0.009*LVEF+3.463*PEP/TET) was strongly correlated to Chen's Ees formula (R = 0.973; R 2 = 0.947) being based on SBP, ESV, LVEF, and PEP/TET and no exponential power. Thus, the new index supports our hypothesis, in the limited sample of patients with HFrEF. Indices like SBP/PEP, (SBP*LVEF)/PEP, PEP/TET, and DBP/SBP deserve further experiments, underlining the major role of the forgotten STI.

Dataset Information

Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure.

Publications

Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets