Effects of carvedilol on structural and functional outcomes and plasma biomarkers in the mouse transverse aortic constriction heart failure model

Effectiveness of pulsatility index of carotid Doppler ultrasonography to predict cardiovascular events

PURPOSE

The pulsatility index (PI) obtained from carotid ultrasonography is considered to be a marker of cerebrovascular resistance. However, the impact of PI on cardiovascular events has yet to be fully addressed.

METHOD

Fifty-four patients who underwent both carotid ultrasonography and coronary angiography were followed for 5.9 ± 3.2 years. The relationship between the incidence of cardiovascular events and PI was investigated.

RESULT

There were 10 (19%) deaths, four (7%) cardiovascular deaths, and nine (17%) major adverse cardiovascular events (MACEs). The cardiovascular events-defined as all hospitalization for MACEs plus heart failure, revascularization, and cardiovascular surgery-occurred in 21 patients (39%). The patients were divided into two groups according to each threshold of PI value for common carotid arteries (CCA), internal carotid arteries (ICA), and external carotid arteries (ECA), respectively. The thresholds were calculated based on receiver-operating characteristic curves for cardiovascular events. Log-rank test showed that the groups with CCA-PI ≥ 1.71, ICA-PI ≥ 1.20, and ECA-PI ≥ 2.46 had a higher incidence of cardiovascular events, respectively (p < 0.05). ECA-PI ≥ 2.46 was associated with an increased incidence of MACEs. Multivariate Cox regression analysis adjusting for cardiovascular risk factors showed that high PI of CCA, ICA, or ECA was a risk factor for cardiovascular events, respectively (CCA-PI ≥ 1.71, hazard ratio (HR) 3.242, p = 0.042; ICA-PI ≥ 1.20, HR 3.639, p = 0.012; ECA-PI ≥ 2.46, HR 11.322, p = 0.001).

CONCLUSION

The results suggested that carotid PIs were independent predictive factors for further cardiovascular events. In particular, high ECA-PI levels may reflect severe arteriosclerosis.

Carvedilol and exercise combination therapy improves systolic but not diastolic function and reduces plasma osteopontin in Col4a3-/- Alport mice

There are currently no Food and Drug Administration-approved treatments for heart failure with preserved ejection fraction (HFpEF). Here we compared the effects of exercise with and without α/β-adrenergic blockade with carvedilol in Col4a3-/- Alport mice, a model of the phenogroup 3 subclass of HFpEF with underlying renal dysfunction. Alport mice were assigned to the following groups: no treatment control (n = 29), carvedilol (n = 11), voluntary exercise (n = 9), and combination carvedilol and exercise (n = 8). Cardiac function was assessed by echocardiography after 4-wk treatments. Running activity of Alport mice was similar to wild types at 1 mo of age but markedly reduced at 2 mo (1.3 ± 0.40 vs. 4.5 ± 1.02 km/day, P < 0.05). There was a nonsignificant trend for increased running activity at 2 mo by carvedilol in the combination treatment group. Combination treatments conferred increased body weight of Col4a3-/- mice (22.0 ± 1.18 vs. 17.8 ± 0.29 g in untreated mice, P < 0.01), suggesting improved physiology, and heart rates declined by similar increments in all carvedilol-treatment groups. The combination treatment improved systolic parameters; stroke volume (30.5 ± 1.99 vs. 17.8 ± 0.77 μL, P < 0.0001) as well as ejection fraction and global longitudinal strain compared with controls. Myocardial performance index was normalized by all interventions (P < 0.0001). Elevated osteopontin plasma levels in control Alport mice were significantly lowered only by combination treatment, and renal function of the Alport group assessed by urine albumin creatinine ratio was significantly improved by all treatments. The results support synergistic roles for exercise and carvedilol to augment cardiac systolic function of Alport mice with moderately improved renal functions but no change in diastole.NEW & NOTEWORTHY In an Alport mouse model of heart failure with preserved ejection fraction (HFpEF), exercise and carvedilol synergistically improved systolic function without affecting diastole. Carvedilol alone or in combination with exercise also improved kidney function. Molecular analyses indicate that the observed improvements in cardiorenal functions were mediated at least in part by effects on serum osteopontin and related inflammatory cytokine cascades. The work presents new potential therapeutic targets and approaches for HFpEF.

Gallic acid improves cardiac dysfunction and fibrosis in pressure overload-induced heart failure

Gallic acid is a trihydroxybenzoic acid found in tea leaves and some plants. Here, we report the effect of gallic acid on cardiac dysfunction and fibrosis in a mouse model of pressure overload-induced heart failure and in primary rat cardiac fibroblasts, and compare the effects of gallic acid with those of drugs used in clinics. Gallic acid reduces cardiac hypertrophy, dysfunction, and fibrosis induced by transverse aortic constriction (TAC) stimuli in vivo and transforming growth factor β1 (TGF-β1) in vitro. It decreases left ventricular end-diastolic and end-systolic diameter, and recovers the reduced fractional shortening in TAC. In addition, it suppresses the expression of atrial natriuretic peptide, brain natriuretic peptide, skeletal α-actin, and β-myosin heavy chain. Administration of gallic acid decreases perivascular fibrosis, as determined by Trichrome II Blue staining, and reduces the expression of collagen type I and connective tissue growth factor. However, administration of losartan, carvedilol, and furosemide does not reduce cardiac dysfunction and fibrosis in TAC. Moreover, treatment with gallic acid inhibits fibrosis-related genes and deposition of collagen type I in TGF-β1-treated cardiac fibroblasts. These results suggest that gallic acid is a therapeutic agent for cardiac dysfunction and fibrosis in chronic heart failure.