Preserved flow-mediated dilation in adults with cyanotic congenital heart disease

Vascular function in adults with cyanotic congenital heart disease

BACKGROUND

Patients with cyanotic congenital heart disease (CCHD) may have a low burden of atherosclerosis. Endothelial dysfunction is an early stage of atherosclerosis and endothelial function is previously studied in smaller CCHD groups with different techniques and variable results. We aimed to examine endothelial function and carotid atherosclerosis in a larger group of CCHD patients.

METHODS

This multicentre study assessed endothelial function in adults with CCHD and controls by measuring the dilatory response of the brachial artery to post-ischemic hyperaemia (endothelium-dependent flow-mediated-vasodilatation (FMD)), and to nitroglycerin (endothelium-independent nitroglycerin-induced dilatation (NID)). Flow was measured at baseline and after ischaemia (reactive hyperaemia). Carotid-intima-media-thickness (CIMT), prevalence of carotid plaque and plaque thickness (cPT-max) were evaluated ultrasonographically. Lipoproteins, inflammatory and vascular markers, including sphingosine-1-phosphate (S1P) were measured.

RESULTS

Forty-five patients with CCHD (median age 50 years) and 45 matched controls (median age 52 years) were included. The patients presented with lower reactive hyperaemia (409 ± 114% vs. 611 ± 248%, p < 0.0001), however preserved FMD response compared to controls (106.5 ± 8.3% vs. 106.4 ± 6.1%, p = 0.95). In contrast, NID was lower in the patients (110.5 ± 6.1% vs. 115.1 ± 7.4%, p = 0.053). There was no difference in CIMT, carotid plaque or cPT-max. The patients presented with lower high-density-lipoprotein cholesterol, and higher level of inflammatory markers and S1P.

CONCLUSION

Adults with CCHD had preserved FMD in the brachial artery, but impaired NID response and lower reactive hyperaemia than controls. The preserved FMD and the comparable prevalence of carotid atherosclerosis indicate that CCHD patients have the same risk of atherosclerosis as controls.

Arterial stiffness and arterial function in adult cyanotic patients with congenital heart disease

BACKGROUND

Mortality in cyanotic patients with congenital heart diseases (CHD) is high, mainly due to cardiovascular complications. It is known that endothelial dysfunction, increased arterial stiffness, and impaired vascular function have negative influence on cardiovascular prognosis. The aim of the study was to assess parameters of arterial stiffness and vascular dysfunction in cyanotic patients with CHD as well as their potential relation to impaired blood oxygen saturation and polycythemia parameters typical for cyanosis.

METHODS

A total of 36 CHD cyanotic patients (17 males) (42.3±16.3 years) and 35 healthy individuals (16 males) (39.6±10.4 years) were enrolled. Assessed parameters were intima media thickness and flow-mediated dilatation (FMD). Assessed parameters using applanation tonometry methods were aortic systolic pressure, aortic pulse pressure (AoPP), augmentation pressure (AP), augmentation index (AI), pulse pressure amplification (PPampl), and pulse wave velocity (PWV).

RESULTS

AoPP (37.3±11.1mmHg vs. 29±6.5mmHg; p=0.002), AP (10.1±7.3mmHg vs. 1.1±3.9mmHg; p=0.00001), AI (24.7±13.5% vs. 3.0±13.6%; p=0.00001), and PWV (7.4±2.1m/s vs. 6.3±0.7m/s; p=0.003) were higher, and PPampl was lower (135.3±16.1% vs. 160.4±12.8%; p=0.00001) in the studied group compared to controls and proved the presence of the increased stiffness of arteries. Impairment of FMD was observed (9.0±5.6 vs. 10.9±4.7; p=0.04). No significant correlations were found between analyzed arterial parameters and biochemical ones characterizing cyanotic patients depicting rheological properties of blood.

CONCLUSIONS

Cyanotic patients with CHD are characterized by increased arterial stiffness estimated with pulse wave analysis parameters and by deteriorated arterial function expressed with worse vasodilatative response in comparison with healthy population. It may confirm relevance of those mechanisms in development of increased rate of cardiovascular events in this population. Association between oxygen saturation or polycythemia and arterial stiffening or vascular dysfunction was not found in these patients.

Widespread endotheliopathy in adults with cyanotic congenital heart disease

INTRODUCTION

Cyanotic congenital heart disease is associated with functional limitation and vascular events. The nature and extent of endothelial dysfunction in cyanotic adults is poorly understood. We sought to characterise endothelial function in this setting.

METHODS

A total of fourteen adults with cyanotic congenital heart disease (40±3 years) together with age- and sex-matched healthy controls underwent assessment of nitric oxide-dependent vascular responses, including flow-mediated dilatation of the brachial artery and dynamic vessel analysis of the retina in response to flickering light. Plasma levels of the endothelium-derived vasoconstrictor endothelin-1 and the nitric oxide antagonist, asymmetric dimethylarginine, were measured. Circulating endothelial progenitor cells were assessed by flow cytometry.

RESULTS

Flow-mediated dilatation was significantly lower in cyanosed adults than controls (4.0±0.8 versus 7.2±1.0%, p=0.019, n=11 per group). Retinal arterial and venous dilatory responses were also impaired (2.9±0.8 versus 5.0±0.6%, p=0.05 and 3.4±0.3 versus 5.2±0.7%, p=0.04, n=13). Serum levels of endothelin-1 and asymmetric dimethylarginine were higher in cyanosed adults (3.0±0.6 versus 1.1±0.1 pg/ml, p=0.004 and 0.68±0.05 versus 0.52±0.02 μmol/L, p=0.03, n=11). Endothelial progenitor cells (CD34+CD45dimCD133+KDR+) were reduced in those with chronic cyanosis (17±4 versus 40±6 per million white blood cells, p=0.005, n=11).

CONCLUSIONS

Endothelial function is impaired in the systemic arteries and retinal vessels in adults with cyanotic congenital heart disease, suggesting a widespread endotheliopathy. Diminished numbers of endothelial progenitor cells might potentially contribute to these observations.

Endothelial function state following repair of cyanotic congenital heart diseases

BACKGROUND

Repairing cyanotic congenital heart disease may be associated with preserving endothelial function. The present study aimed to evaluate vascular endothelial function in patients with repaired cyanotic congenital heart disease.

METHODS

In a case-control study conducted in 2012 in Isfahan, Iran, 42 consecutive patients aged <35 years who had suffered from different types of cyanotic congenital heart disease and had undergone complete repair of their congenital heart defect were assessed in regard to their endothelial function state by measuring flow-mediated dilatation and other cardiac function indices. They were paired with 42 sex- and age-matched healthy controls.

RESULTS

The mean flow-mediated dilatation was lower in patients with repaired cyanotic congenital heart disease than in the controls [6.14±2.78 versus 8.16±1.49 respectively (p<0.001)]. Significant adverse correlations were found between flow-mediated dilatation, age, and body mass indexes, in those who underwent repair surgery. In addition, flow-mediated dilatation had a positive association with the shortening fraction, ejection fraction, and tricuspid annular plane systolic excursion value, and it was also inversely associated with carotid intima-media thickness and the myocardial performance index. The mean of the flow-mediated dilatation was significantly higher in the group with tetralogy of Fallot along with complete repair before the age of 2.5 years and also in those patients with total anomalous pulmonary venous connection or transposition of the great arteries repaired with an arterial switch operation before 6 months of age, compared with the other two subgroups. This includes patients with a tetralogy of Fallot defect repaired after 4 years of age and those with complex cyanotic congenital heart disease that was repaired after 2.5 years of age (mean age at repair 9±6.1 years).

CONCLUSION

Early repair of a cyanotic defect can result in the protection of vascular endothelial function and prevent the occurrence of vascular accidents at an older age.

Endothelial dysfunction and atherosclerosis in children with irreversible pulmonary hypertension due to congenital heart disease

OBJECTIVE

To assess endothelial dysfunction and the risk for coronary atherosclerosis in children with irreversible pulmonary hypertension due to congenital heart disease (CHD).

METHODS

The study included 18 cyanotic patients (the mean age was 12.28 ± 3.26 years) who developed irreversible pulmonary hypertension due to cyanotic and acyanotic CHDs, and 18 control patients (the mean age was 11.78 ± 3.00 years). Study groups were compared for flow-mediated dilatation (FMD), carotid intima media thickness (CIMT) and atherosclerotic risk factors.

RESULTS

Compared to the control group, the mean FMD was significantly reduced in the cyanotic group (5.26 ± 2.42% and 9.48 ± 2.60%, respectively; P-value < 0.001). No significant difference was observed between the groups in CIMT (0.41 ± 0.08 mm and 0.39 ± 0.06 mm, respectively; P-value = 0.299). The levels of total cholesterol, low-density lipoprotein-cholesterol and very low-density lipoprotein-cholesterol were statistically significantly lower compared tothe control group (P-value = 0.001, 0.006 and 0.014, respectively), whereas no statistically significant difference was found in the levels of high-density lipoprotein-cholesterol and triglycerides (P-value = 0.113 and 0.975, respectively).

CONCLUSIONS

Systemic endothelial dysfunction in children with irreversible pulmonary hypertension due to CHD was noted but there was no increased risk for atherosclerosis.