Effects of alirocumab on endothelial function and coronary atherosclerosis in myocardial infarction: A PACMAN-AMI randomized clinical trial substudy

BACKGROUND AND AIMS

The effects of protein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on endothelial function as assessed by flow-mediated dilation (FMD) in patients with acute myocardial infarction (AMI) are unknown. Therefore, we aimed to investigate the effects of the PCSK9 inhibitor alirocumab added to high-intensity statin on FMD, and its association with coronary atherosclerosis in non-infarct related arteries using intracoronary intravascular ultrasound (IVUS), near-infrared spectroscopy (NIRS), and optical coherence tomography (OCT).

METHODS

This was a pre-specified substudy among patients recruited at Bern University Hospital, Switzerland, for the randomized-controlled, double-blind, PACMAN-AMI trial, which compared the effects of biweekly alirocumab 150 mg vs. placebo added to rosuvastatin. Brachial artery FMD was measured at 4 and 52 weeks, and intracoronary imaging at baseline and 52 weeks.

RESULTS

139/173 patients completed the substudy. There was no difference in FMD at 52 weeks in the alirocumab (n = 68, 5.44 ± 2.24%) versus placebo (n = 71, 5.45 ± 2.19%) group (difference = -0.21%, 95% CI -0.77 to 0.35, p = 0.47). FMD improved throughout 52 weeks in both groups similarly (p < 0.001). There was a significant association between 4 weeks FMD and baseline plaque burden (IVUS) (n = 139, slope = -1.00, p = 0.006), but not with lipid pool (NIRS) (n = 139, slope = -7.36, p = 0.32), or fibrous cap thickness (OCT) (n = 81, slope = -1.57, p = 0.62).

CONCLUSIONS

Among patients with AMI, the addition of alirocumab did not result in further improvement of FMD as compared to 52 weeks secondary preventative medical therapy including high-intensity statin therapy. FMD was significantly associated with coronary plaque burden at baseline, but not with lipid pool or fibrous cap thickness.

Case report of a rare cause of secondary hypertension illustrating the importance of cardio-obstetric preconception counselling

Background

Cardiovascular diseases represent a leading cause of maternal morbidity and mortality in industrialized countries. High blood pressure during pregnancy is a major driver of short- and long-term cardiovascular health in both mother and child. Screening and adequate treatment of elevated blood pressure before pregnancy significantly reduce mortality risk to mother and child.

Case summary

A 30-year-old woman with middle aortic coarctation (MAC) previously treated with aortic stenting was referred to our cardio-obstetrics with plans to become pregnant. The clinical examination revealed severe hypertension with a significant blood pressure gradient between the upper and lower limbs. The patient underwent computed tomography angiography showing re-stenosis of the aorta. After the analysis of the benefit risk of all treatment options, percutaneous transluminal aortic in-stent re-stenting was performed. Following the intervention, blood pressure profile significantly improved but remained slightly elevated further necessitating the introduction of an antihypertensive therapy.

Discussion

This clinical case condenses several challenges encountered in the management of hypertension in women who plan to become pregnant. Firstly, it emphasizes the fact that secondary causes of chronic hypertension, including MAC, do not have to be overlooked in childbearing age patient. Secondly, it illustrates the need for a multidisciplinary analysis of all available treatment options in view of a future pregnancy. Finally, it discusses the particular follow-up and potential complications in pregnant women with MAC and aortic stent.

The influence of cardiac arrhythmias on the detection of heartbeats in the photoplethysmogram: benchmarking open-source algorithms

Objective.Cardiac arrhythmias are a leading cause of mortality worldwide. Wearable devices based on photoplethysmography give the opportunity to screen large populations, hence allowing for an earlier detection of pathological rhythms that might reduce the risks of complications and medical costs. While most of beat detection algorithms have been evaluated on normal sinus rhythm or atrial fibrillation recordings, the performance of these algorithms in patients with other cardiac arrhythmias, such as ventricular tachycardia or bigeminy, remain unknown to date.Approach. ThePPG-beatsopen-source framework, developed by Charlton and colleagues, evaluates the performance of the beat detectors namedQPPG,MSPTDandABDamong others. We applied thePPG-beatsframework on two newly acquired datasets, one containing seven different types of cardiac arrhythmia in hospital settings, and another dataset including two cardiac arrhythmias in ambulatory settings.Main Results. In a clinical setting, theQPPGbeat detector performed best on atrial fibrillation (with a medianF1score of 94.4%), atrial flutter (95.2%), atrial tachycardia (87.0%), sinus rhythm (97.7%), ventricular tachycardia (83.9%) and was ranked 2nd for bigeminy (75.7%) behindABDdetector (76.1%). In an ambulatory setting, theMSPTDbeat detector performed best on normal sinus rhythm (94.6%), and theQPPGdetector on atrial fibrillation (91.6%) and bigeminy (80.0%).Significance. Overall, the PPG beat detectorsQPPG,MSPTDandABDconsistently achieved higher performances than other detectors. However, the detection of beats from wrist-PPG signals is compromised in presence of bigeminy or ventricular tachycardia.

Blood pressure variability, nocturnal heart rate variability and endothelial function predict recurrent cerebro-cardiovascular events following ischemic stroke

Introduction

Cardiovascular parameters characterizing blood pressure (BP), heart rate (HR), endothelial function and arterial stiffness predict cerebro-cardiovascular events (CCVE) in the general population. Considering the paucity of data in stroke patients, we assessed these parameters as potential predictors of recurrent CCVE at acute stroke stroke.

Patients and methods

This is a secondary outcome analysis of a prospective observational longitudinal Sleep Deficiency & Stroke Outcome Study (ClinicalTrials.gov Identifier: NCT02559739). The study consecutively recruited acute ischemic stroke patients. Cardiovascular parameters (blood pressure variability [BPV], heart rate variability [HRV], endothelial function, and arterial stiffness) were assessed within the first week post-stroke. Future CCVE were recorded over a 3-year follow-up. Multivariate Cox regression analysis was used to investigate the prognostic value of 48 cardiovascular parameters regarding CCVE risk.

Results

Out of 447 recruited patients, 359 were included in this analysis. 20% of patients developed a future CCVE. A high variability of systolic BP (n = 333) and nocturnal HR (non-linear parameters; n = 187) at acute stroke predicted CCVE risk after adjustment for demographic parameters, cardiovascular risk factors and mean BP or HR, respectively. Endothelial dysfunction (n = 105) at acute stroke predicted CCVE risk after adjustment for age and sex, but not after adjustment for cardiovascular risk factors. Diurnal HR and arterial stiffness at acute stroke were not associated with CCVE risk.

Conclusion

High blood pressure variability, high nocturnal HRV and endothelial function contribute to the risk for future CCVE after stroke.

Method-comparison study between a watch-like sensor and a cuff-based device for 24-h ambulatory blood pressure monitoring

The use of 24-h ambulatory blood pressure monitoring (ABPM) has been continuously increasing over the last decades. However, cuff-based devices may cause discomfort, particularly at night, leading to potentially non-representative blood pressure (BP) values. We investigated the feasibility of a cuff-less BP monitoring solution in 67 subjects undergoing conventional 24-h ABPM. A watch-like optical sensor was attached at the upper arm or wrist at the contralateral side of the cuff. Systolic (SBP) and diastolic BP (DBP) values were estimated from the measured optical signals by pulse wave analysis. Average 24-h, daytime and nighttime BP values were compared between the conventional monitor and the cuff-less sensor. The differences between both methods-expressed as mean ± standard deviation (95% limits of agreement)-were of - 1.8 ± 6.2 mmHg (- 13.9, 10.3) on SBP and - 2.3 ± 5.4 mmHg (- 13.0, 8.3) on DBP for 24-h averages, of - 1.5 ± 6.6 mmHg (- 14.4, 11.4) on SBP and - 1.8 ± 5.9 mmHg (- 13.4, 9.9) on DBP for daytime averages, and of 0.4 ± 7.5 mmHg (- 14.4, 15.1) on SBP and - 1.3 ± 6.8 mmHg (- 14.7, 12.0) on DBP for nighttime averages. These results encouragingly suggest that cuff-less 24-h ABPM may soon become a clinical possibility.

Increased Arterial Responsiveness to Angiotensin II in Mice Conceived by Assisted Reproductive Technologies

Since the first report in 1978, the number of individuals conceived by Assisted Reproductive Technologies (ART) has grown incessantly. In parallel, with the recent emergence of possible underlying mechanisms of ART-induced epigenetic changes in the renin-angiotensin system, the cardiovascular repercussions of ART in mice and human offspring (including arterial hypertension, vascular dysfunction, and cardiac remodeling) have become increasingly recognized. Here, we hypothesized that ART may increase arterial responsiveness to angiotensin II (ANG II) by epigenetically modifying the expression of its receptors. To test this hypothesis, we assessed the vasoconstrictor responsiveness to ANG II in isolated aortas from ART and control mice. We also examined ANG II receptor (ATR) type 1 and 2 expression and the promoter methylation of the At1aR, At1bR and At2R genes. We found that the vasoconstrictor response to ANG II was markedly increased in ART mice compared to controls. This exaggerated vasoconstrictor responsiveness in ART mice correlated with a significant increase in the ANG II receptor (ATR) type 1 to ATR type 2 protein expression ratio in the aorta; this was mainly driven by an increase in AT1R expression, and by hypomethylation of two CpG sites located in the At1bR gene promoter leading to increased transcription of the gene. We conclude that in mice, ART increase the vasoconstrictor response to ANG II in the aorta by epigenetically causing an imbalance between the expression of vasoconstrictor (AT1R) and vasodilator (AT2R) ANG II receptors. Unbalanced expression of AT1R and AT2R receptors seems to be a novel mechanism contributing to ART-induced arterial hypertension in mice.

Effect of alirocumab added to high-Intensity statin therapy on endothelial function in patients with acute myocardial infarction: a sub-study of the randomized placebo-controlled PACMAN-AMI trial

Background

Endothelial dysfunction is involved early in the development of vascular dysfunction leading to atherosclerosis and cardiovascular diseases. Statins have shown to improve endothelial function. The role of the protein convertase subtilisin/kexin type 9-inhibitor (PCSK9) alirocumab on endothelial function among patients with acute myocardial infarction (AMI) remains unknown.

Purpose

We investigated the effect of alirocumab on endothelial function among AMI patients receiving PCSK9i alirocumab in addition to high intensity statin therapy.

Methods

This is a pre-specified, sub-study nested within the PACMAN-AMI (effects of the PCSK9 antibody AliroCuMab on coronary Atherosclerosis in patieNts with Acute Myocardial Infarction) trial, a randomized trial that compared the effects of biweekly PCSK9-inhibitor alirocumab 150 mg vs. placebo, initiated within 24h of presentation in patients with AMI on top of high-intensity statin. Patients recruited at Bern University Hospital and adherent to the study drug (alirocumab or placebo) were analysed for the current study. Endothelial function was assessed by flow mediated dilation (FMD) of the brachial artery at week 4 and 52 after treatment initiation.

Results

Among 139 patients (68 alirocumab, 71 placebo) completing the sub-study, baseline characteristics were well balanced between groups (alirocumab vs. placebo: mean age 57.5±10.1 years vs. 58.7±8.4 years, p=0.45; mean LDL-C 4.03±0.93 mmol/L vs. 4.05±0.74 mmol/L, p=NS). At week 52 LDL-C levels decreased to 0.65±0.71 mmol/L in the alirocumab group and to 1.98±0.71 mmol/L in the placebo group (p&lt;0.001). There was no difference in FMD at 52 weeks in the alirocumab (5.44±2.24%) versus placebo (5.45±2.19%) group (between groups difference FMD, −0.21% (95% CI −077 to 0.35), p=0.47). Compared to baseline, follow-up FMD was improved in both groups (from 4.52±1.87 to 5.44±2.24%, p&lt;0.001 in the alirocumab group and from 4.32±1.62 to 5.45±2.19%, p&lt;0.001 in the placebo group).

Conclusion

Among patients with acute myocardial infarction, the addition of subcutaneous biweekly alirocumab, compared with placebo, to high-intensity statin therapy did not result in additional improvement of endothelial function after 52 weeks of treatment.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): The PACMAN-AMI study was supported by a research grant from Sanofi, Regeneron and Infraredx. This substudy was funded by the University of Bern.

Renal denervation in the antihypertensive arsenal - knowns and known unknowns

Even though it has been more than a decade since renal denervation (RDN) was first used to treat hypertension and an intense effort on researching this therapy has been made, it is still not clear how RDN fits into the antihypertensive arsenal. There is no question that RDN lowers blood pressure (BP), it does so to an extent at best corresponding to one antihypertensive drug. The procedure has an excellent safety record. However, it remains clinically impossible to predict whose BP responds to RDN and whose does not. Long-term efficacy data on BP reduction are still unconvincing despite the recent results in the SPYRAL HTN-ON MED trial; experimental studies indicate that reinnervation is occurring after RDN. Although BP is an acceptable surrogate endpoint, there is complete lack of outcome data with RDN. Clear indications for RDN are lacking although patients with resistant hypertension, those with documented increase in activity of the sympathetic system and perhaps those who desire to take fewest medication may be considered.

EPR spectroscopic evidence of iron-catalysed free radical formation in chronic mountain sickness: Dietary causes and vascular consequences

Chronic mountain sickness (CMS) is a high-altitude (HA) maladaptation syndrome characterised by elevated systemic oxidative-nitrosative stress (OXNOS) due to a free radical-mediated reduction in vascular nitric oxide (NO) bioavailability. To better define underlying mechanisms and vascular consequences, this study compared healthy male lowlanders (80 m, n = 10) against age/sex-matched highlanders born and bred in La Paz, Bolivia (3600 m) with (CMS+, n = 10) and without (CMS-, n = 10) CMS. Cephalic venous blood was assayed using electron paramagnetic resonance spectroscopy and reductive ozone-based chemiluminescence. Nutritional intake was assessed via dietary recall. Systemic vascular function and structure were assessed via flow-mediated dilatation, aortic pulse wave velocity and carotid intima-media thickness using duplex ultrasound and applanation tonometry. Basal systemic OXNOS was permanently elevated in highlanders (P = <0.001 vs. lowlanders) and further exaggerated in CMS+, reflected by increased hydroxyl radical spin adduct formation (P = <0.001 vs. CMS-) subsequent to liberation of free 'catalytic' iron consistent with a Fenton and/or nucleophilic addition mechanism(s). This was accompanied by elevated global protein carbonylation (P = 0.046 vs. CMS-) and corresponding reduction in plasma nitrite (P = <0.001 vs. lowlanders). Dietary intake of vitamins C and E, carotene, magnesium and retinol were lower in highlanders and especially deficient in CMS + due to reduced consumption of fruit and vegetables (P = <0.001 to 0.028 vs. lowlanders/CMS-). Systemic vascular function and structure were also impaired in highlanders (P = <0.001 to 0.040 vs. lowlanders) with more marked dysfunction observed in CMS+ (P = 0.035 to 0.043 vs. CMS-) in direct proportion to systemic OXNOS (r = -0.692 to 0.595, P = <0.001 to 0.045). Collectively, these findings suggest that lifelong exposure to iron-catalysed systemic OXNOS, compounded by a dietary deficiency of antioxidant micronutrients, likely contributes to the systemic vascular complications and increased morbidity/mortality in CMS+. TRIAL REGISTRY: ClinicalTrials.gov; No: NCT01182792; URL: www.clinicaltrials.gov.

In vitro fertilization exacerbates stroke size and neurological disability in wildtype mice

BACKGROUND AND PURPOSE

Assisted reproductive technologies (ART) induce premature vascular aging in human offspring. The related alterations are well-established risk factors for stroke and predictors of adverse stroke outcome. However, given the young age of the human ART population there is no information on the incidence and outcome of cerebrovascular complications in humans. In mice, ART alters the cardiovascular phenotype similarly to humans, thereby offering the possibility to study this problem.

METHODS

We investigated the morphological and clinical outcome after ischemia/reperfusion brain injury induced by transient (45 min) middle cerebral artery occlusion in ART and control mice.

RESULTS

We found that stroke volumes were almost 3-fold larger in ART than in control mice (P < 0.001). In line with these morphological differences, neurological performance assessed by the Bederson and RotaRod tests 24 and 48 h after artery occlusion was significantly worse in ART compared with control mice. Plasma levels of TNF-alpha, were also significantly increased in ART vs. control mice after stroke (P < 0.05). As potential underlying mechanisms, we identified increased blood-brain barrier permeability evidenced by increased IgG extravasation associated with decreased tight junctional protein claudin-5 and occludin expression, increased oxidative stress and decreased NO-bioactivity in ART compared with control mice.

CONCLUSIONS

In wildtype mice, ART predisposes to significantly worse morphological and functional stroke outcomes, related at least in part to altered blood-brain barrier permeability. These findings demonstrate that ART, by inducing premature vascular aging, not only is a likely risk factor for stroke-occurrence, but also a mediator of adverse stroke-outcome.

TRANSLATIONAL PERSPECTIVE

This study highlights that ART not only is a likely risk factor for stroke-occurrence, but also a mediator of adverse stroke-outcome. The findings should raise awareness in the ever-growing human ART population in whom these techniques cause similar alterations of the cardiovascular phenotype and encourage early preventive and diagnostic efforts.

Evaluation of a cuffless watch-like sensor for 24-hour ambulatory blood pressure monitoring

Introduction

Ambulatory blood pressure monitoring (ABPM) is increasingly used in clinical practice for the formal diagnosis of hypertension, and particularly indicated in cases of suspected white-coat effect, masked, or nocturnal hypertension. However, the use of cuffs for ABPM may be painful and cause discomfort, particularly at night, where it may even provoke arousal from sleep and lead to non-representative nighttime blood pressure (BP) values.

Purpose

To investigate the feasibility of using a cuffless watch-like photoplethysmographic (PPG) sensor for 24-hour ABPM by comparing the PPG-based BP estimates with conventional cuff-derived ABPM values.

Methods

Our study was approved by the local ethical committee and conducted in 70 participants (43±18 y, 35 with hypertension, 41 male) undergoing cuff-based ABPM. At the contralateral side of the cuff, a cuffless watch-like PPG sensor was worn at the wrist or upper arm. Systolic (SBP) and diastolic (DBP) BP values were estimated by pulse wave analysis on the measured PPG signals. Following a calibration procedure, the PPG-based daytime and nighttime BP estimates were compared to their cuff-based counterparts. The agreement between both methods was evaluated via the mean (bias) and standard deviation (SD) of their differences by Bland-Altman analysis. The agreement on the nocturnal dipping estimates of both devices was also assessed. Finally, the concordance rate (CR) was assessed as the percentage of dipping values showing a concordant direction (dipping vs. non-dipping) between both methods.

Results

The data of 4 participants were incomplete due to technical issues and had to be rejected prior to analysis. In 4 additional participants, the PPG data quality was insufficient to provide enough BP estimates, probably due to poor sensor tightening. In the remaining 62 participants, we found (see Figure 1) differences between the daytime PPG-based and cuff-based BP estimates of −0.9±3.6 mmHg and −1.4±2.9 mmHg for SBP and DBP, respectively. The differences between the nighttime estimates were −0.8±6.8 mmHg and 0.5±5.3 mmHg, resulting in dipping differences of 0.1±6.8% and −2.0±8.6% for SBP and DBP, respectively. CR on dipping was 97% for both SBP and DBP.

Conclusions

Good agreement was found between the PPG-based and the cuff-based daytime and nighttime BP averages, with generally negligible (∼1 mmHg) biases. The direction of dipping was highly concordant between both methods. The estimation of its amplitude showed a low bias (∼1%) but a non-negligible spread (SD), which can be in part attributed to the uncertainty on the cuff-based dipping estimates (95% confidence interval range of 12.5% and 16.5% on average for SBP and DBP, respectively), more than twice as large than their PPG-based counterparts (5.7% and 7.8%). Although our study was designed as a method-comparison feasibility study, these results encouragingly suggest that cuffless ABPM may soon become a clinical possibility.

Funding Acknowledgement

Type of funding sources: None. Figure 1

POS0794 INCIDENCE AND PHENOTYPE OF ANTIPHOSPHOLIPID SYNDROME (APS) AFTER PREECLAMPSIA

Background:

Obstetric Antiphospholipid syndrom (oAPS) is induced by antiphospholipid antibodies (aPL) and associated with specific pregnancy complications. oAPS requires the combination of at least one obstetrical and one laboratory criteria (in 2 or more occasions at least 12 weeks apart). Multiple aPL positivity, lupus anticoagulant (LA) or persistently high aPL titers is defined as high risk aPL profile. “Non-criteria” oAPS are cases not fulfilling the clinical criteria.

Objectives:

To investigate the incidence of aPL after preeclampsia and the association of phenotypes of oAPS and pregnancy outcome.

Methods:

The present retrospective cohort analysis included women followed up after preeclampsia. Anti-PL (LA, aCL, anti-β2GBI of IgG and IgM isotype) are assessed 8 to 12 weeks after PE and if positive, again at least 12 weeks apart. According to the ISSHP PE is classified as severe if the blood pressure exceeds 160/110mmHg, or is associated with HELLP syndrome, or eclampsia. FGR is defined as estimated fetal weight <5th, and birth weight <10th percentile, and/or pathologic fetal Doppler.

Results:

Complete clinical and laboratory data were available for 99 women over a period of 6 years. 38.4% delivered <34 + 0 weeks. PE was severe in 63.6% of cases, and the incidence of FGR was 58.9%. HELLP syndrome was diagnosed in 34.3% and in 4 cases it was isolated. The prevalence of aPL was 35 (35.4%) at first evaluation, and 23 (23.2%) were still positive 12 weeks apart. 14/99 (14.1%) cases fulfilled the definition of classical oAPS, and 9/99 (9.1%) delivered >34 weeks (“non-criteria oAPS”). Of interest, the incidende og high risk aPL profiles was similar in both groups (64.3% vs. 77.8%; p=NS). The incidence of HELLP syndrome was higher in the presence of APS (APS: 9/23 [39.1%] vs. 21/76 [27.6%]; p=NS). 3 out of 4 cases with isolated HELLP syndrome were associated with high risk aPL profiles. Overall, aCL IgG was the dominant aPL. 32/35 (91.4%) and 22/23 (95.7%) had positive aCL at first and second investigation, respectively (p=NS). An aCL IgG titer >32.8CU at first assessment yield a LR of 10 for persistent aCL with a sensitivity and specificity of 91.3% and 90.9%, respectively.

Conclusion:

Classical and “non-criteria” obstetrical APS show a similar aPL pattern and distribution of aPL phenotypes regardless of gestational age at delivery. aCL IgG is the dominant aPL antibody and is highly predictive for aPL persistence at follow up. HELLP syndrome may be an additional feature of oAPS, in particular the isolated form. However, more studies are necessary to explore this possible association.

References:

[1]Tektonidou MG et al, EULAR recommendations for the management of antiphospholipid syndrome in adults Ann Rheum Dis. 2019 Oct;78(10):1296-1304. doi: 10.1136/annrheumdis-2019-215213. Epub 2019 May 15.

Disclosure of Interests:

None declared

Sodium intake, life expectancy, and all-cause mortality

AIMS

Since dietary sodium intake has been identified as a risk factor for cardiovascular disease and premature death, a high sodium intake can be expected to curtail life span. We tested this hypothesis by analysing the relationship between sodium intake and life expectancy as well as survival in 181 countries worldwide.

METHODS AND RESULTS

We correlated age-standardized estimates of country-specific average sodium consumption with healthy life expectancy at birth and at age of 60 years, death due to non-communicable diseases and all-cause mortality for the year of 2010, after adjusting for potential confounders such as gross domestic product per capita and body mass index. We considered global health estimates as provided by World Health Organization. Among the 181 countries included in this analysis, we found a positive correlation between sodium intake and healthy life expectancy at birth (β = 2.6 years/g of daily sodium intake, R2 = 0.66, P < 0.001), as well as healthy life expectancy at age 60 (β = 0.3 years/g of daily sodium intake, R2 = 0.60, P = 0.048) but not for death due to non-communicable diseases (β = 17 events/g of daily sodium intake, R2 = 0.43, P = 0.100). Conversely, all-cause mortality correlated inversely with sodium intake (β = -131 events/g of daily sodium intake, R2 = 0.60, P < 0.001). In a sensitivity analysis restricted to 46 countries in the highest income class, sodium intake continued to correlate positively with healthy life expectancy at birth (β = 3.4 years/g of daily sodium intake, R2 = 0.53, P < 0.001) and inversely with all-cause mortality (β = -168 events/g of daily sodium intake, R2 = 0.50, P < 0.001).

CONCLUSION

Our observation of sodium intake correlating positively with life expectancy and inversely with all-cause mortality worldwide and in high-income countries argues against dietary sodium intake being a culprit of curtailing life span or a risk factor for premature death. These data are observational and should not be used as a base for nutritional interventions.

[The Long-COVID Syndrome - a New Clinical Picture after COVID-19 Infection]

The Long-COVID Syndrome - a New Clinical Picture after COVID-19 Infection Abstract. Long-term consequences are increasingly reported in the current literature after COVID-19 infections. Some patients suffer from persistent pulmonary and extrapulmonary symptoms even months after the acute infection. Pulmonary impairment, but also dysregulation and effects on immune system, cardiovascular system, neurological system, skin and kidney are described or anticipated. This mini review gives a short update to the practitioner about the current knowledge about Long COVID.

Non-invasive pulmonary artery pressure estimation by electrical impedance tomography in a controlled hypoxemia study in healthy subjects

Pulmonary hypertension is a hemodynamic disorder defined by an abnormal elevation of pulmonary artery pressure (PAP). Current options for measuring PAP are limited in clinical practice. The aim of this study was to evaluate if electrical impedance tomography (EIT), a radiation-free and non-invasive monitoring technique, can be used for the continuous, unsupervised and safe monitoring of PAP. In 30 healthy volunteers we induced gradual increases in systolic PAP (SPAP) by exposure to normobaric hypoxemia. At various stages of the protocol, the SPAP of the subjects was estimated by transthoracic echocardiography. In parallel, in the pulmonary vasculature, pulse wave velocity was estimated by EIT and calibrated to pressure units. Within-cohort agreement between both methods on SPAP estimation was assessed through Bland-Altman analysis and at subject level, with Pearson's correlation coefficient. There was good agreement between the two methods (inter-method difference not significant (P > 0.05), bias ± standard deviation of - 0.1 ± 4.5 mmHg) independently of the degree of PAP, from baseline oxygen saturation levels to profound hypoxemia. At subject level, the median per-subject agreement was 0.7 ± 3.8 mmHg and Pearson's correlation coefficient 0.87 (P < 0.05). Our results demonstrate the feasibility of accurately assessing changes in SPAP by EIT in healthy volunteers. If confirmed in a patient population, the non-invasive and unsupervised day-to-day monitoring of SPAP could facilitate the clinical management of patients with pulmonary hypertension.

P5359Pulmonary artery pressure is elevated three month after delivery in patients with preeclampsia and antiphospholipid syndrome

Introduction

Preeclampsia (PE) is a multisystem disease affecting 2–8% of all pregnancies. Recently we found that the prevalence of antiphospholipid syndrome (APS) in PE patients at 13.9%. APS can be the cause of thromboembolic pulmonary hypertension. However, data on heart function and pulmonary pressure in PE and in PE with APS are sparse.

Purpose

We sought to investigate cardiac hemodynamics in this population.

Method

Between July 2016 and December 2018, we performed echocardiography in patients who had suffered from PE alone (n=102, age=32.6±4.8 y) or PE with APS (n=21, age=32.1±4.2 y) 3 months after delivery. APS was diagnosed according to the Sapporo criteria.

Results

The overall prevalence of APS was 17%. Right ventricular to right atrial pressure (RV/RA) gradient was significantly higher in PE + APS patients than in patients who had PE only (21.1±3.8 vs. 17.9±4.6mmHg, p=0.04, PE+APS vs. PE). The indexed volume of the left atrium (LA: 20.3±4.4 vs 23.5±5.5ml/m2, p=0.01, PE+APS vs. PE) and the birthweight of the newborn (1379.8±759.1 vs 1848.1±879.6.1g, p=0.02, PE+APS vs. PE) were lower in APS patients.

Conclusion

In patients with preeclampsia and APS, three month after delivery, pulmonary artery pressure was higher and the left atrium size smaller than in patients who had PE only. Conceivably this may reflects multiple subclinical clots in the pulmonary vessels in APS patients and may put these patients at an elevated risk of pulmonary hypertension later in life.

Association of Assisted Reproductive Technologies With Arterial Hypertension During Adolescence

BACKGROUND

Assisted reproductive technologies (ART) have been shown to induce premature vascular aging in apparently healthy children. In mice, ART-induced premature vascular aging evolves into arterial hypertension. Given the young age of the human ART group, long-term sequelae of ART-induced alterations of the cardiovascular phenotype are unknown.

OBJECTIVES

This study hypothesized that vascular alterations persist in adolescents and young adults conceived by ART and that arterial hypertension possibly represents the first detectable clinically relevant endpoint in this group.

METHODS

Five years after the initial assessment, the study investigators reassessed vascular function and performed 24-h ambulatory blood pressure (BP) monitoring (ABPM) in 54 young, apparently healthy participants conceived through ART and 43 age- and sex-matched controls.

RESULTS

Premature vascular aging persisted in ART-conceived subjects, as evidenced by a roughly 25% impairment of flow-mediated dilation of the brachial artery (p < 0.001) and increased pulse-wave velocity and carotid intima-media thickness. Most importantly, ABPM values (systolic BP, 119.8 ± 9.1 mm Hg vs. 115.7 ± 7.0 mm Hg, p = 0.03; diastolic BP, 71.4 ± 6.1 mm Hg vs. 69.1 ± 4.2 mm Hg, p = 0.02 ART vs. control) and BP variability were markedly higher in ART-conceived subjects than in control subjects. Eight of the 52 ART participants, but only 1 of the 43 control participants (p = 0.041 ART vs. controls) fulfilled ABPM criteria of arterial hypertension (>130/80 mm Hg and/or >95th percentile).

CONCLUSIONS

ART-induced premature vascular aging persists in apparently healthy adolescents and young adults without any other detectable classical cardiovascular risk factors and progresses to arterial hypertension. (Vascular Dysfunction in Offspring of Assisted Reproduction Technologies; NCT00837642.).

Exaggerated systemic oxidative-inflammatory-nitrosative stress in chronic mountain sickness is associated with cognitive decline and depression

KEY POINTS

Chronic mountain sickness (CMS) is a maladaptation syndrome encountered at high altitude (HA) characterised by severe hypoxaemia that carries a higher risk of stroke and migraine and is associated with increased morbidity and mortality. We examined if exaggerated oxidative-inflammatory-nitrosative stress (OXINOS) and corresponding decrease in vascular nitric oxide bioavailability in patients with CMS (CMS+) is associated with impaired cerebrovascular function and adverse neurological outcome. Systemic OXINOS was markedly elevated in CMS+ compared to healthy HA (CMS-) and low-altitude controls. OXINOS was associated with blunted cerebral perfusion and vasoreactivity to hypercapnia, impaired cognition and, in CMS+, symptoms of depression. These findings are the first to suggest that a physiological continuum exists for hypoxaemia-induced systemic OXINOS in HA dwellers that when excessive is associated with accelerated cognitive decline and depression, helping identify those in need of more specialist neurological assessment and targeted support.

ABSTRACT

Chronic mountain sickness (CMS) is a maladaptation syndrome encountered at high altitude (HA) characterised by severe hypoxaemia that carries a higher risk of stroke and migraine and is associated with increased morbidity and mortality. The present cross-sectional study examined to what extent exaggerated systemic oxidative-inflammatory-nitrosative stress (OXINOS), defined by an increase in free radical formation and corresponding decrease in vascular nitric oxide (NO) bioavailability, is associated with impaired cerebrovascular function, accelerated cognitive decline and depression in CMS. Venous blood was obtained from healthy male lowlanders (80 m, n = 17), and age- and gender-matched HA dwellers born and bred in La Paz, Bolivia (3600 m) with (CMS+, n = 23) and without (CMS-, n = 14) CMS. We sampled blood for oxidative (electron paramagnetic resonance spectroscopy, HPLC), nitrosative (ozone-based chemiluminescence) and inflammatory (fluorescence) biomarkers. We employed transcranial Doppler ultrasound to measure cerebral blood flow (CBF) and reactivity. We utilised psychometric tests and validated questionnaires to assess cognition and depression. Highlanders exhibited elevated systemic OXINOS (P < 0.05 vs. lowlanders) that was especially exaggerated in the more hypoxaemic CMS+ patients (P < 0.05 vs. CMS-). OXINOS was associated with blunted cerebral perfusion and vasoreactivity to hypercapnia, impaired cognition and, in CMS+, symptoms of depression. Collectively, these findings are the first to suggest that a physiological continuum exists for hypoxaemia-induced OXINOS in HA dwellers that when excessive is associated with accelerated cognitive decline and depression, helping identify those in need of specialist neurological assessment and support.

Assisted Reproductive Technologies Predispose to Insulin Resistance and Obesity in Male Mice Challenged With a High-Fat Diet

Assisted reproductive technology (ART) alters glucose homeostasis in mice and humans, but the underlying mechanisms are incompletely understood. ART induces endothelial dysfunction and arterial hypertension by epigenetic alteration of the endothelial nitric oxide synthase (eNOS) gene. In eNOS-deficient mice, insulin resistance is related to impaired insulin stimulation of muscle blood flow and substrate delivery and defective intrinsic skeletal muscle glucose uptake. We therefore assessed glucose tolerance, insulin sensitivity (euglycemic clamp), insulin stimulation of muscle blood flow in vivo, and muscle glucose uptake in vitro in male ART and control mice fed a normal chow (NC) or challenged with a high-fat diet (HFD) during 8 weeks. Glucose tolerance and insulin sensitivity were similar in NC-fed animals. When challenged with a HFD, however, ART mice developed exaggerated obesity, fasting hyperinsulinemia and hyperglycemia, and a 20% lower insulin-stimulated glucose utilization than did control mice (steady-state glucose infusion rate (GIR), 51.3 ± 7.3 vs 64.0 ± 10.8 mg/kg/min, P = 0.012). ART-induced insulin resistance was associated with defective insulin stimulation of muscle blood flow, whereas intrinsic skeletal muscle glucose uptake was normal. In conclusion, ART-induced endothelial dysfunction, when challenged with a metabolic stress, facilitates glucose intolerance and insulin resistance. Similar mechanisms may contribute to ART-induced alterations of the metabolic phenotype in humans.

Mediation of coffee-induced improvements in human vascular function by chlorogenic acids and its metabolites: Two randomized, controlled, crossover intervention trials

BACKGROUND & AIMS

Polyphenol intake has been linked to improvements in human vascular function, although data on hydroxycinnamates, such as chlorogenic acid (CGA) have not yet been studied. We aimed to investigate the impact of coffee intake rich in chlorogenic acid on human vascular function and whether CGAs are involved in potential effects.

METHODS

Two acute randomized, controlled, cross-over human intervention trials were conducted. The impact of coffee intake, matched for caffeine but differing in CGA content (89, and 310 mg) on flow-mediated dilatation (FMD) was assessed in 15 healthy male subjects. In a second intervention trial conducted with 24 healthy male subjects, the impact of pure 5-caffeoylquinic acid (5-CQA), the main CGA in coffee (5-CQA; 450 mg and 900 mg) on FMD was also investigated.

RESULTS

We observed a bi-phasic FMD response after low and high polyphenol, (89 mg and 310 mg CGA) intake, with increases at 1 (1.10 ± 0.43% and 1.34 ± 0.62%, respectively) and 5 (0.79% ± 0.32 and 1.52% ± 0.40, respectively) hours post coffee consumption. FMD responses to coffee intake was closely paralleled by the appearance of CGA metabolites in plasma, notably 3-, 4- and 5-feruloylquinic acid and ferulic-4'-O-sulfate at 1 h and isoferulic-3'-O-glucuronide and ferulic-4'-O-sulfate at 5 h. Intervention with purified 5-CQA (450 mg) also led to an improvement in FMD response relative to control (0.75 ± 1.31% at 1 h post intervention, p = 0.06) and concomitant appearance of plasma metabolites.

CONCLUSIONS

Coffee intake acutely improves human vascular function, an effect, in part, mediated by 5-CQA and its physiological metabolites.

STUDY REGISTRATION

The National Institutes of Health (NIH) on ClinicalTrials.govNCT01813981 and NCT01772784.

Patent foramen ovale: a novel cardiovascular risk factor in patients with sleep disordered breathing and high altitude dwellers?

Diseases associated with chronic hypoxaemia are a leading cause of morbidity and mortality in Western countries. Epidemiological data indicate that cardiovascular diseases contribute substantially to this problem, but the underlying mechanisms are incompletely understood. Sleep disordered breathing and high altitude exposure are frequent conditions associated with hypoxaemia. Recent evidence suggests that in these conditions the concomitant presence of a patent foramen ovale plays an important pathogenic role. For example, in patients with obstructive sleep apnoea the presence of a patent foramen ovale is associated with more severe sleep disordered breathing, nocturnal oxygen desaturation, generalised endothelial dysfunction and arterial hypertension. After patent foramen ovale closure, both sleep disordered breathing and cardiovascular phenotype improve, suggesting the existence of a possible causal link. During short-term high altitude exposure, the presence of a patent foramen ovale, by aggravating altitude-induced hypoxaemia, facilitates exaggerated pulmonary hypertension. Interestingly, there is increasing evidence showing that in high-altitude dwellers a patent foramen ovale also alters the cardiovascular phenotype. In this article we will summarise recent evidence demonstrating how a patent foramen ovale alters the cardiovascular phenotype and increases cardiovascular risk in patients with sleep disordered breathing and high-altitude dwellers.

Effects of perinatal, late foetal, and early embryonic insults on the cardiovascular phenotype in experimental animal models and humans

Cardiovascular diseases are the main cause of mortality and morbidity in Western countries, but the underlying mechanisms are still poorly understood. Genetic polymorphisms, once thought to represent a major determinant of cardiovascular risk, individually and collectively, only explain a tiny fraction of phenotypic variation and disease risk in humans. It is now clear that non-genetic factors, i.e., factors that modify gene activity without changing the DNA sequence and that are sensitive to the environment can cause important alterations of the cardiovascular phenotype in experimental animal models and humans. Here, we will review recent studies demonstrating that distinct pathological events during the perinatal (transient perinatal hypoxemia), late foetal (preeclampsia), and early embryonic (assisted reproductive technologies) periods induce profound alterations of the cardiovascular phenotype in humans and experimental animals. Moreover, we will provide evidence that epigenetic modifications are contributing importantly to this problem and are conferring the potential for its transmission to subsequent generations.

Abstract P101: Assisted Reproductive Technologies Increase the Vasoconstrictor Responsiveness to Angiotensin II by an Epigenetic Mechanism

Environmental influences acting early in life predispose to premature cardiovascular disease. In line with this concept, assisted reproductive technologies (ART) cause premature vascular ageing and arterial hypertension in mice and humans, but the underlying mechanisms are incompletely understood. In rodents, pathological events during pregnancy cause arterial hypertension in the offspring by increasing the vascular responsiveness to angiotensin II (ANG II). We speculated that a similar mechanism could be involved in ART-induced arterial hypertension. In aortic ring preparations of ART and control mice, we, therefore, assessed the vasoconstrictor responsiveness to stepwise increasing doses of ANG II in the presence of the eNOS inhibitor L-NMA. We also examined ANG II receptor (AGTR) type 1 and 2 expression (Western Blot) and AGTR gene promoter methylation (bisulfite sequencing) in the aorta. Finally, we measured mesenteric-artery responsiveness to acetylcholine and arterial blood pressure (carotid catheter). As expected, ART mice displayed endothelial dysfunction (P=.03, vs. control) and arterial hypertension (121.8±7.3 vs. 114.6±4.5 [mmHg], P=.02, vs. control). Most importantly, the vasoconstrictor response to ANG II, independently of endothelial function, was markedly increased in ART compared to control mice (0.32±0.05 vs. 0.22±0.04 [% of maximal KCl contraction], P<.01, vs. control). Moreover, and in line with this finding, in ART mice AGTR 1/AGTR 2 ratio of protein expression in the aorta was significantly increased (1.49±0.30 vs. 0.36±0.16, P<.008, vs. control) and the AGTR 1b gene promoter was hypomethylated compared with control mice (8.1±4.3 vs. 10.6±1.6 [% of methylation], P<.05, vs. control). Here, we show for the first time that ART increases the vasoconstrictor sensitivity to ANG II in the aorta. This is related to an epigenetically mediated imbalance between the expression of the vasoconstrictor (AGTR 1) and vasodilatator (AGTR 2) ANG II receptor. Hence, we identified a new mechanism contributing to ART-induced premature vascular ageing and arterial hypertension in mice. We speculate that this mechanism also contributes to ART-induced premature vascular ageing and arterial hypertension in humans.

Acute and Chronic Altitude-Induced Cognitive Dysfunction in Children and Adolescents

OBJECTIVE

To assess whether exposure to high altitude induces cognitive dysfunction in young healthy European children and adolescents during acute, short-term exposure to an altitude of 3450 m and in an age-matched European population permanently living at this altitude.

STUDY DESIGN

We tested executive function (inhibition, shifting, and working memory), memory (verbal, short-term visuospatial, and verbal episodic memory), and speed processing ability in: (1) 48 healthy nonacclimatized European children and adolescents, 24 hours after arrival at high altitude and 3 months after return to low altitude; (2) 21 matched European subjects permanently living at high altitude; and (3) a matched control group tested twice at low altitude.

RESULTS

Short-term hypoxia significantly impaired all but 2 (visuospatial memory and processing speed) of the neuropsychological abilities that were tested. These impairments were even more severe in the children permanently living at high altitude. Three months after return to low altitude, the neuropsychological performances significantly improved and were comparable with those observed in the control group tested only at low altitude.

CONCLUSIONS

Acute short-term exposure to an altitude at which major tourist destinations are located induces marked executive and memory deficits in healthy children. These deficits are equally marked or more severe in children permanently living at high altitude and are expected to impair their learning abilities.

Sleep-Disordered Breathing and Vascular Function in Patients With Chronic Mountain Sickness and Healthy High-Altitude Dwellers

BACKGROUND

Chronic mountain sickness (CMS) is often associated with vascular dysfunction, but the underlying mechanism is unknown. Sleep-disordered breathing (SDB) frequently occurs at high altitude. At low altitude, SDB causes vascular dysfunction. Moreover, in SDB, transient elevations of right-sided cardiac pressure may cause right-to-left shunting in the presence of a patent foramen ovale (PFO) and, in turn, further aggravate hypoxemia and pulmonary hypertension. We speculated that SDB and nocturnal hypoxemia are more pronounced in patients with CMS compared with healthy high-altitude dwellers, and are related to vascular dysfunction.

METHODS

We performed overnight sleep recordings, and measured systemic and pulmonary artery pressure in 23 patients with CMS (mean ± SD age, 52.8 ± 9.8 y) and 12 healthy control subjects (47.8 ± 7.8 y) at 3,600 m. In a subgroup of 15 subjects with SDB, we assessed the presence of a PFO with transesophageal echocardiography.

RESULTS

The major new findings were that in patients with CMS, (1) SDB and nocturnal hypoxemia was more severe (P < .01) than in control subjects (apnea-hypopnea index [AHI], 38.9 ± 25.5 vs 14.3 ± 7.8 number of events per hour [nb/h]; arterial oxygen saturation, 80.2% ± 3.6% vs 86.8% ± 1.7%, CMS vs control group), and (2) AHI was directly correlated with systemic blood pressure (r = 0.5216; P = .001) and pulmonary artery pressure (r = 0.4497; P = .024). PFO was associated with more severe SDB (AHI, 48.8 ± 24.7 vs 14.8 ± 7.3 nb/h; P = .013, PFO vs no PFO) and hypoxemia.

CONCLUSIONS

SDB and nocturnal hypoxemia are more severe in patients with CMS than in control subjects and are associated with systemic and pulmonary vascular dysfunction. The presence of a PFO appeared to further aggravate SDB. Closure of the PFO may improve SDB, hypoxemia, and vascular dysfunction in patients with CMS.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01182792; URL: www.clinicaltrials.gov.

Novel Insights into Cardiovascular Regulation in Patients with Chronic Mountain Sickness

Studies of high-altitude populations, and in particular of maladapted subgroups, may provide important insight into underlying mechanisms involved in the pathogenesis of hypoxemia-related disease in general. Chronic mountain sickness (CMS) is a major public health problem in mountainous regions of the world affecting many millions of high-altitude dwellers. It is characterized by exaggerated chronic hypoxemia, erythrocytosis, and mild pulmonary hypertension. In later stages these patients often present with right heart failure and are predisposed to systemic cardiovascular disease, but the underlying mechanisms are poorly understood. Here, we present recent new data providing insight into underlying mechanisms that may cause these complications.

Patent Foramen Ovale Closure in Obstructive Sleep Apnea Improves Blood Pressure and Cardiovascular Function

Obstructive sleep apnea (OSA) is a frequent syndrome characterized by intermittent hypoxemia and increased prevalence of arterial hypertension and cardiovascular morbidity. In OSA, the presence of patent foramen ovale (PFO) is associated with increased number of apneas and more severe oxygen desaturation. We hypothesized that PFO closure improves sleep-disordered breathing and, in turn, has favorable effects on vascular function and arterial blood pressure. In 40 consecutive patients with newly diagnosed OSA, we searched for PFO. After initial cardiovascular assessment, the 14 patients with PFO underwent initial device closure and the 26 without PFO served as control group. Conventional treatment for OSA was postponed for 3 months in both groups, and polysomnographic and cardiovascular examinations were repeated at the end of the follow-up period. PFO closure significantly improved the apnea-hypopnea index (ΔAHI -7.9±10.4 versus +4.7±13.1 events/h, P=0.0009, PFO closure versus control), the oxygen desaturation index (ΔODI -7.6±16.6 versus +7.6±17.0 events/h, P=0.01), and the number of patients with severe OSA decreased significantly after PFO closure (79% versus 21%, P=0.007). The following cardiovascular parameters improved significantly in the PFO closure group, although remained unchanged in controls: brachial artery flow-mediated vasodilation, carotid artery stiffness, nocturnal systolic and diastolic blood pressure (-7 mm Hg, P=0.009 and -3 mm Hg, P=0.04, respectively), blood pressure dipping, and left ventricular diastolic function. In conclusion, PFO closure in OSA patients improves sleep-disordered breathing and nocturnal oxygenation. This translates into an improvement of endothelial function and vascular stiffening, a decrease of nighttime blood pressure, restoration of the dipping pattern, and improvement of left ventricular diastolic function.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01780207.

Abstract 092: Low Birth Weight per se Is Not a Determinant of Vascular Dysfunction and Presumably Future Cardiovascular Risk in Humans

Background: Epidemiological studies suggest that low birth weight (BW) is associated with systemic vascular dysfunction and premature cardiovascular morbidity and mortality later in life. However, this association could be due to confounding factors associated with low BW, such as genetic factors, pathological events during intrauterine life, and maternal or early-life environmental insults. Studies of monozygotic twins born with significantly different BW provide a unique opportunity to control for these potential confounding factors, thereby allowing to directly study the effect of low BW per se on systemic vascular function later in life.

Methods: We, therefore, measured flow-mediated dilation (FMD) of the brachial artery, carotid-femoral pulse wave velocity (PWV) and carotid intima-media thickness (IMT) in 13 monozygotic, monochorionic healthy twins pairs (mean±SD age, 13.5±3.4 years) who were born with significantly different BW (defined as >20% BW difference within pairs, 2310±600 vs. 1800±520 g, P<0.0001) and in 26 healthy age- and sex-matched control subjects born at term with normal BW (3460±360 g). None of the participants had suffered from intrauterine or perinatal complications.

Results: The major new findings were two fold; 1) systemic vascular function was comparable in low and high BW twins (FMD, 9.0±1.8 vs. 8.7±2.0%; PWV, 6.5±1.3 vs. 6.6±0.9 m/s; IMT, 390±30 vs. 390±20μm, all P values >0.2, low vs. high BW) and 2) systemic vascular function in twins was similar to the one observed in control singletons (FMD, 8.8±1.3 vs.8.9±1.8%, P=0.95; PWV: 6.5±1.1 vs. 6.6±1.2 m/s, P=0.80; IMT: 390±25 vs. 385±20μm, P=0.33, singletons vs. twins). Finally, there existed no relationship between BW and vascular function in the whole study population (FMD: r=0.001, P=0.99).

Conclusions: This study provides the first direct evidence in humans that low BW per se is not a determinant of systemic vascular dysfunction (and presumably future cardiovascular risk). Moreover, it indicates that independent of BW, vascular function in twins is normal. We suggest that the association between low BW and increased cardiovascular risk reported in earlier epidemiological studies was related to confounding factors associated with low BW.

Prevention of vascular dysfunction and arterial hypertension in mice generated by assisted reproductive technologies by addition of melatonin to culture media

Assisted reproductive technologies (ART) induce vascular dysfunction in humans and mice. In mice, ART-induced vascular dysfunction is related to epigenetic alteration of the endothelial nitric oxide synthase (eNOS) gene, resulting in decreased vascular eNOS expression and nitrite/nitrate synthesis. Melatonin is involved in epigenetic regulation, and its administration to sterile women improves the success rate of ART. We hypothesized that addition of melatonin to culture media may prevent ART-induced epigenetic and cardiovascular alterations in mice. We, therefore, assessed mesenteric-artery responses to acetylcholine and arterial blood pressure, together with DNA methylation of the eNOS gene promoter in vascular tissue and nitric oxide plasma concentration in 12-wk-old ART mice generated with and without addition of melatonin to culture media and in control mice. As expected, acetylcholine-induced mesenteric-artery dilation was impaired (P = 0.008 vs. control) and mean arterial blood pressure increased (109.5 ± 3.8 vs. 104.0 ± 4.7 mmHg, P = 0.002, ART vs. control) in ART compared with control mice. These alterations were associated with altered DNA methylation of the eNOS gene promoter (P < 0.001 vs. control) and decreased plasma nitric oxide concentration (10.1 ± 11.1 vs. 29.5 ± 8.0 μM) (P < 0.001 ART vs. control). Addition of melatonin (10(-6) M) to culture media prevented eNOS dysmethylation (P = 0.005, vs. ART + vehicle), normalized nitric oxide plasma concentration (23.1 ± 14.6 μM, P = 0.002 vs. ART + vehicle) and mesentery-artery responsiveness to acetylcholine (P < 0.008 vs. ART + vehicle), and prevented arterial hypertension (104.6 ± 3.4 mmHg, P < 0.003 vs. ART + vehicle). These findings provide proof of principle that modification of culture media prevents ART-induced vascular dysfunction. We speculate that this approach will also allow preventing ART-induced premature atherosclerosis in humans.

Right ventricular dysfunction in children and adolescents conceived by assisted reproductive technologies

Assisted reproductive technologies (ART) predispose the offspring to vascular dysfunction, arterial hypertension, and hypoxic pulmonary hypertension. Recently, cardiac remodeling and dysfunction during fetal and early postnatal life have been reported in offspring of ART, but it is not known whether these cardiac alterations persist later in life and whether confounding factors contribute to this problem. We, therefore, assessed cardiac function and pulmonary artery pressure by echocardiography in 54 healthy children conceived by ART (mean age 11.5 ± 2.4 yr) and 54 age-matched (12.2 ± 2.3 yr) and sex-matched control children. Because ART is often associated with low birth weight and prematurity, two potential confounders associated with cardiac dysfunction, only singletons born with normal birth weight at term were studied. Moreover, because cardiac remodeling in infants conceived by ART was observed in utero, a situation associated with increased right heart load, we also assessed cardiac function during high-altitude exposure, a condition associated with hypoxic pulmonary hypertension-induced right ventricular overload. We found that, while at low altitude cardiac morphometry and function was not different between children conceived by ART and control children, under the stressful conditions of high-altitude-induced pressure overload and hypoxia, larger right ventricular end-diastolic area and diastolic dysfunction (evidenced by lower E-wave tissue Doppler velocity and A-wave tissue Doppler velocity of the lateral tricuspid annulus) were detectable in children and adolescents conceived by ART. In conclusion, right ventricular dysfunction persists in children and adolescents conceived by ART. These cardiac alterations appear to be related to ART per se rather than to low birth weight or prematurity.