Effect of exercise training on vascular function and endothelial repair in heart failure with preserved ejection fraction: results from the OptimEx trial

Background

Exercise training improves peak oxygen uptake (VO2) in heart failure with preserved ejection fraction (HFpEF), but the underlying mechanisms are unknown. In other cardiovascular diseases, exercise training improves vascular function and increases levels of circulating endothelium-repairing cells. We aimed to investigate the effects of moderate continuous training (MCT) and high intensity interval training (HIIT) on vascular function and cellular endothelial repair in HFpEF.

Methods

This was a prespecified subanalysis of the Optimizing Exercise Training in Prevention and Treatment of Diastolic Heart Failure randomized trial. HFpEF patients (n=180) were randomized to HIIT, MCT or attention control. At baseline and after 12 weeks, we measured peak VO2, fingertip arterial tonometry (n=109), brachial artery flow-mediated dilation (n=59), aortic pulse wave velocity (n=94), and flow cytometry (n=136) for endothelial progenitor cells (CD45dimCD34+VEGFR2+) and angiogenic T cells (CD3+CD31+CD184+). Changes in these parameters were compared between groups using linear mixed models. Parameters were correlated using Spearman's rho.

Results

At 3 months, we did not observe significant differences between HIIT, MCT and control group regarding changes in vascular function throughout the vascular tree (fingertip arterial tonometry, brachial artery flow-mediated dilation and central arterial stiffness, Table 1) or levels of circulating endothelium-repairing cells (endothelial progenitor cells and angiogenic T cells, Table 1). Results were similar at 12 months and when restricting analysis to patients with at least 70% adherence to training sessions. Patients with higher peak VO2 at baseline had lower numbers of circulating endothelial progenitor cells (rho=−0.22, p=0.011).

Conclusions

In patients with HFpEF, exercise training did not change vascular function or levels of endothelium-repairing cells. Thus, improved vascular function likely does not contribute to the change in peak VO2 after training. These findings are in contrast with the benefits of exercise on vascular function in heart failure with reduced ejection fraction and coronary artery disease.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): EU Framework Programme 7 Table 1

Effects of low- or high-dose hormone therapy on fasting and post-methionine homocysteine levels in postmenopausal women

OBJECTIVE

To evaluate the effect of two different hormone therapy (HT) doses on fasting and post-methionine homocysteine levels, an independent risk factor for cardiovascular and thromboembolic diseases.

METHODS

Forty-eight women in natural postmenopause randomly received calcium 1 mg/day (control group; n = 12) or calcium plus low dose (1 mg estradiol plus 0.5 mg norethisterone; n = 18) or high dose (2 mg estradiol plus 1 mg norethisterone; n = 18) HT in a 6-month randomized, controlled, prospective study.

RESULTS

Folate levels did not vary in any group, while levels of vitamin B12 significantly decreased after low- (-12.2 +/- 6.6%; p < 0.04) or high-dose HT (-13.9 +/- 6.1%; p < 0.01). Fasting homocysteine was reduced by either HT dose in a way that was inversely related to pretreatment homocysteine levels (-0.675x; r = 0.644; p < 0.0001). Modification of post-load homocysteine increase was influenced by the HT dose and inversely related to the homocysteine response to methionine observed at baseline. The regression slope observed with the low-dose HT (-1.637x; r = 0.57; p < 0.02) was significantly steeper (p < 0.001) than that observed with the high-dose HT (-0.304x; r = 0.554; p < 0.03) dose.

CONCLUSIONS

Low- or high-dose HT similarly influences fasting homocysteine levels. Low-dose HT seems to be more effective than high-dose HT in reducing the post-methionine homocysteine increase.

Early prenatal diagnosis of recurrent 46,XY partial gonadal dysgenesis

OBJECTIVES

We present a case of early prenatal diagnosis of recurrent 46,XY partial gonadal dysgenesis, by combining early genetic and sonographic evaluations.

METHODS

The conceptus of a mother with a first child affected by 46,XY gonadal dysgenesis was sonographically evaluated at 21- and 23-mm BPD (12(+2) and 12(+6) LMP-based age) and the female genitalia were observed. Karyotype analyses was performed on amniotic fluid and it revealed a 46,XY complement without mosaicism. SRY was amplified by PCR for molecular analyses.

RESULTS

We observed a discordance between female phenotype detected at 21 and 23 mm of biparietal diameter (12(+2) and 12(+6) LMP-based age) and male karyotype. In the child and the fetus, seminiferous cords were not recognisable, whereas rare Leydig cells and no germ cells could be identified. Internal and external genitalia were sexually ambiguous in the child and feminized in the fetus.

CONCLUSION

This is the first case of early prenatal diagnosis of recurrent 46,XY partial gonadal dysgenesis and it points to the importance of combining early analyses of genetic sex with sonography in the management of anomalies of sexual development, with particular regard to syndromes for which the risk of recurrence is little understood.

Continuous combined hormone replacement therapy with oral 17beta-estradiol and norethisterone acetate improves homocysteine metabolism in postmenopausal women

OBJECTIVE

To evaluate the effect of a continuous combined oral hormone replacement therapy (HRT) on basal and post-methionine load homocysteine levels in postmenopausal women.

DESIGN

Twenty-two postmenopausal women (PMW) were randomly allocated to receive either continuous combined oral HRT (2 mg of estradiol plus 1 mg of norethisterone acetate; n = 11) or no treatment (controls, n = 11) for 6 months. A methionine oral load (0.1 g/kg body weight) was performed in each subject at time 0 and after 6 months. Serum homocysteine levels were measured by high-performance liquid chromatography in samples collected at time 0 and at 4, 8, and 24 h after the methionine load, while levels of vitamin B6 (by high-performance liquid chromatography) and B12 and folate (both by ELISA) were assayed in samples collected at time 0.

RESULTS

Serum levels of glucose and body mass index increased in treated PMW, whereas folate decreased in controls. In treated PMW, basal homocysteine tended to decrease (10.6 +/- 3.3 micromol/L vs. 9.62 +/- 2.8 micromol/L, p = 0.062), whereas in controls it significantly increased (10.7 +/- 2.65 micromol/L vs. 12.17 +/- 3.89 micromol/L, p < 0.05). This increase was not significant after correction for vitamin status (p = 0.072). Homocysteine values 4 h (31.9 +/- 13.53 micromol/L vs. 39.83 +/- 22.53 micromol/L, p < 0.05) and 8 h (35.1 +/- 13.13 vs. 43.34 +/- 22.15 micromol/L) after methionine, and integrated homocysteine response to methionine (392.5 +/- 133.8 micromol/24 h vs. 458.8 +/- 104.8 micromol/24 h; p < 0.05), were significantly reduced in HRT-treated, but not in untreated, PMW.

CONCLUSIONS

Continuous combined oral HRT with17beta-estradiol plus norethisterone acetate reduces homocysteine levels, mainly after a methionine load. This effect seems to be independent of vitamin status and may have positive implications for the prevention of cardiovascular diseases in PMW.