Inhibition of superoxide and iNOS augment cutaneous nitric oxide-dependent vasodilation in non-Hispanic black young adults.

We assessed the combined effect of superoxide and iNOS inhibition on microvascular function in non-Hispanic Black and non-Hispanic White participants (n = 15 per group). Participants were instrumented with four microdialysis fibers: (1) lactated Ringer's (control), (2) 10 µM tempol (superoxide inhibition), (3) 0.1 mM 1400 W (iNOS inhibition), (4) tempol + 1400 W. Cutaneous vasodilation was induced via local heating and NO-dependent vasodilation was quantified. At control sites, NO-dependent vasodilation was lower in non-Hispanic Black (45 ± 9% NO) relative to non-Hispanic White (79 ± 9% NO; p < 0.01; effect size, d = 3.78) participants. Tempol (62 ± 16% NO), 1400 W (78 ± 12% NO) and tempol +1400 W (80 ± 13% NO) increased NO-dependent vasodilation in non-Hispanic Black participants relative to control sites (all p < 0.01; d = 1.22, 3.05, 3.03, respectively). The effect of 1400 W (p = 0.04, d = 1.11) and tempol +1400 W (p = 0.03, d = 1.22) was greater than tempol in non-Hispanic Black participants. There was no difference between non-Hispanic Black and non-Hispanic White participants at 1400 W or tempol + 1400 W sites. These data suggest iNOS has a greater effect on NO-dependent vasodilation than superoxide in non-Hispanic Black participants.

Longitudinal Aortic Root Dilatation in Collegiate American-Style Football Athletes.

Background Clinically relevant aortic dilatation (>40 mm) and increased cardiovascular risk are common among retired professional American-style football athletes. Among younger athletes, the effect of American-style football participation on aortic size is incompletely understood. We sought to determine changes in aortic root (AR) size and associated cardiovascular phenotypes across the collegiate career. Methods and Results This was a multicenter, longitudinal repeated-measures observational cohort study of athletes across 3 years of elite collegiate American-style football participation. A total of 247 athletes (119 [48%] Black, 126 [51%] White, 2 [1%] Latino; 91 [37%] linemen, 156 [63%] non-linemen) were enrolled as freshmen and studied at pre- and postseason year 1, postseason year 2 (N=140 athletes), and postseason year 3 (N=82 athletes). AR size was measured with transthoracic echocardiography. AR diameter increased over the study period from 31.7 (95% CI, 31.4-32.0) to 33.5 mm (95% CI, 33.1-33.8; P<0.001). No athlete developed an AR ≥40 mm. Athletes also demonstrated increased weight (cumulative mean Δ, 5.0 [95% CI, 4.1-6.0] kg, P<0.001), systolic blood pressure (cumulative mean Δ, 10.6 [95% CI, 8.0-13.2] mm Hg, P<0.001), pulse wave velocity (cumulative mean Δ, 0.43 [95% CI, 0.31-0.56] m/s, P<0.001), and left ventricular mass index (cumulative mean Δ, 21.2 [95% CI, 19.2-23.3] g/m2, P<0.001), and decreased E' velocity (cumulative mean Δ, -2.4 [95%CI, -2.9 to -1.9] cm/s, P<0.001). Adjusting for height, player position, systolic blood pressure, and diastolic blood pressure, higher weight (ß=0.030, P=0.003), pulse wave velocity (ß=0.215, P=0.02), and left ventricular mass index (ß=0.032, P<0.001) and lower E' (ß=-0.082, P=0.001) were associated with increased AR diameter. Conclusions Over the collegiate American-style football career, athletes demonstrate progressive AR dilatation associated with cardiac and vascular functional impairment. Future studies delineating aortic outcomes are necessary to determine whether AR dilation is indicative of maladaptive vascular remodeling in this population.

Contribution of sensory nerves to cutaneous reactive hyperaemia in non-Hispanic Black and White young adults.

NEW FINDINGS: What is the central question of this study? Does cutaneous sensory nerve-mediated vasodilatation differ between non-Hispanic Black and White young adults? What is the main finding and its importance? The magnitude of cutaneous reactive hyperaemia is lower in non-Hispanic Black relative to non-Hispanic White young adults, but the overall sensory nerve contribution is the same, suggesting that sensory nerve function is similar in both non-Hispanic Black and White young adults. ABSTRACT: The aim of this study was to assess cutaneous sensory nerve function, independent of nitric oxide, in non-Hispanic Black and White young adults. We tested the hypothesis that cutaneous reactive hyperaemia and sensory nerve-mediated vasodilatation would be lower in non-Hispanic Black young adults relative to non-Hispanic White young adults. Twenty-four participants who self-identified as non-Hispanic Black (n = 12) or non-Hispanic White (n = 12) were recruited. All participants underwent three bouts of reactive hyperaemia. An index of skin blood flow was measured continuously using laser-Doppler flowmetry at a control site and at a site treated with topical 4% lignocaine to inhibit sensory nerve function. Peak reactive hyperaemia was lower in non-Hispanic Black relative to non-Hispanic White participants (P < 0.001). Total reactive hyperaemia was lower in non-Hispanic Black [mean (SD); control, 4085 (955)%CVCmax  s; lignocaine, 2127 (639) percent maximal cutaneous vascular conductance * seconds, %CVCmax  s] relative to non-Hispanic White [control: 6820 (1179)%CVCmax  s; lignocaine, 3573 (712)%CVCmax  s] participants (P < 0.001 for both sites). There was no difference between groups for the calculated contribution of sensory nerves to either the peak [non-Hispanic Black, 25 (14)%; non-Hispanic White, 19 (13)%] or total reactive hyperaemic response [non-Hispanic Black, 48 (10)%; non-Hispanic White, 47 (10)%]. These data suggest that cutaneous reactive hyperaemia is lower in non-Hispanic Black young adults, but the sensory nerve contribution is similar in non-Hispanic Black and White young adults.

Effects of biological sex and oral contraceptive pill use on cutaneous microvascular endothelial function and nitric oxide-dependent vasodilation in humans.

The purpose of this study was to evaluate in vivo endothelial function and nitric oxide (NO)-dependent vasodilation between women in either menstrual or placebo pill phases of their respective hormonal exposure [either naturally cycling (NC) or using oral contraceptive pills (OCPs)] and men. A planned subgroup analysis was then completed to assess endothelial function and NO-dependent vasodilation between NC women, women using OCP, and men. Endothelium-dependent and NO-dependent vasodilation were assessed in the cutaneous microvasculature using laser-Doppler flowmetry, a rapid local heating protocol (39°C, 0.1 °C/s), and pharmacological perfusion through intradermal microdialysis fibers. Data are represented as means ± standard deviation. Men displayed greater endothelium-dependent vasodilation (plateau, men: 71 ± 16 vs. women: 52 ± 20%CVCmax, P < 0.01), but lower NO-dependent vasodilation (men: 52 ± 11 vs. women: 63 ± 17%NO, P = 0.05) compared with all women. Subgroup analysis revealed NC women had lower endothelium-dependent vasodilation (plateau, NC women: 48 ± 21%CVCmax, P = 0.01) but similar NO-dependent vasodilation (NC women: 52 ± 14%NO, P > 0.99), compared with men. Endothelium-dependent vasodilation did not differ between women using OCP and men (P = 0.12) or NC women (P = 0.64), but NO-dependent vasodilation was significantly greater in women using OCP (74 ± 11%NO) than both NC women and men (P < 0.01 for both). This study highlights the importance of directly quantifying NO-dependent vasodilation in cutaneous microvascular studies. This study also provides important implications for experimental design and data interpretation.NEW & NOTEWORTHY This study supports differences in microvascular endothelial function and nitric oxide (NO)-dependent vasodilation between women in low hormone phases of two hormonal exposures and men. However, when separated into subgroups of hormonal exposure, women during placebo pills of oral contraceptive pill (OCP) use have greater NO-dependent vasodilation than naturally cycling women in their menstrual phase and men. These data improve knowledge of sex differences and the effect of OCP use on microvascular endothelial function.

Endothelin A receptor inhibition increases nitric oxide-dependent vasodilation independent of superoxide in non-Hispanic Black young adults.

Young non-Hispanic Black adults have reduced microvascular endothelial function compared with non-Hispanic White counterparts, but the mechanisms are not fully elucidated. The purpose of this study was to investigate the effect of endothelin-1 A receptor (ETAR) and superoxide on cutaneous microvascular function in young non-Hispanic Black (n = 10) and White (n = 10) adults. Participants were instrumented with four intradermal microdialysis fibers: 1) lactated Ringer's (control), 2) 500 nM BQ-123 (ETAR antagonist), 3) 10 µM tempol (superoxide dismutase mimetic), and 4) BQ-123 + tempol. Skin blood flow was assessed via laser-Doppler flowmetry (LDF), and each site underwent rapid local heating from 33°C to 39°C. At the plateau of local heating, 20 mM l-NAME [nitric oxide (NO) synthase inhibitor] was infused to quantify NO-dependent vasodilation. Data are means ± standard deviation. NO-dependent vasodilation was decreased in non-Hispanic Black compared with non-Hispanic White young adults (P < 0.01). NO-dependent vasodilation was increased at BQ-123 sites (73 ± 10% NO) and at BQ-123 + tempol sites (71 ± 10%NO) in non-Hispanic Black young adults compared with control (53 ± 13%NO, P = 0.01). Tempol alone had no effect on NO-dependent vasodilation in non-Hispanic Black young adults (63 ± 14%NO, P = 0.18). NO-dependent vasodilation at BQ-123 sites was not statistically different between non-Hispanic Black and White (80 ± 7%NO) young adults (P = 0.15). ETAR contributes to reduced NO-dependent vasodilation in non-Hispanic Black young adults independent of superoxide, suggesting a greater effect on NO synthesis rather than NO scavenging via superoxide.NEW & NOTEWORTHY Endothelin-1 A receptors (ETARs) have been shown to reduce endothelial function independently and through increased production of superoxide. We show that independent ETAR inhibition increases microvascular endothelial function in non-Hispanic Black young adults. However, administration of a superoxide dismutase mimetic alone and in combination with ETAR inhibition had no effect on microvascular endothelial function suggesting that, in the cutaneous microvasculature, the negative effects of ETAR in non-Hispanic Black young adults are independent of superoxide production.

Microvascular endothelial function following cessation of long-term oral contraceptive pill use: A case report.

NEW FINDINGS: What is the main observation in this case? The main observation of this case report is substantial improvement in cutaneous microvascular endothelial function after cessation of long-term use of a fourth-generation oral contraceptive pill. This improvement appears independent of relative changes in the contribution of nitric oxide. What insights does it reveal? Our findings suggest that cessation of long-term, fourth-generation oral contraceptive pill use improves endothelial function within 20 months of cessation. ABSTRACT: The purpose of this case report was to evaluate in vivo endothelial function and nitric oxide (NO)-dependent vasodilatation before and after the cessation of long-term (11-12 years) fourth-generation oral contraceptive pill (OCP) use in one young, healthy and premenopausal woman. This retrospective analysis includes data from six experimental visits: three visits during months 133-144 of fourth-generation OCP use and three visits 19-22 months after OCP cessation. Endothelium-dependent and NO-dependent vasodilatation were assessed in the cutaneous microvasculature using laser-Doppler flowmetry, a rapid local heating protocol (39°C, 0.1°C/s) and pharmacological perfusion through intradermal microdialysis fibres. The participant had consistent medical history and lifestyle behaviours throughout both hormonal exposures. Data are presented as the mean (SD). Endothelium-dependent vasodilatation was 42 (10)% of site-specific maximal cutaneous vascular conductance (CVCmax ) during OCP use and 63 (10)%CVCmax after OCP cessation (49% increase). Nitric oxide-dependent vasodilatation was 70 (5)% contribution of NO during OCP use and 60 (15)%NO after OCP cessation (15% reduction). Baseline blood flow was greater after OCP cessation, but maximal blood flow was reduced. Data from this case report support a substantial increase in cutaneous microvascular endothelial function assessed via local heating after cessation of long-term use of a fourth-generation OCP, which does not appear to be attributable to increased NO bioavailability. Overall, these data suggest an improvement in endothelial and microvascular function after the cessation of long-term use of a fourth-generation OCP.

Metabolic Alterations Differentiating Cardiovascular Maladaptation from Athletic Training in American-Style Football Athletes.

PURPOSE: Metabolomics identifies molecular products produced in response to numerous stimuli, including both adaptive (includes exercise training) and disease processes. We analyzed a longitudinal cohort of American-style football (ASF) athletes, who reliably acquire maladaptive cardiovascular (CV) phenotypes during competitive training, with high-resolution metabolomics to determine whether metabolomics can discriminate exercise-induced CV adaptations from early CV pathology. METHODS: Matched discovery ( n = 42) and validation ( n = 40) multicenter cohorts of collegiate freshman ASF athletes were studied with longitudinal echocardiography, applanation tonometry, and high-resolution metabolomics. Liquid chromatography-mass spectrometry identified metabolites that changed ( P < 0.05, false discovery rate <0.2) over the season. Metabolites demonstrating similar changes in both cohorts were further analyzed in linear and mixed-effects models to identify those associated with left ventricular mass, tissue-Doppler myocardial E ' velocity (diastolic function), and arterial function (pulse wave velocity). RESULTS: In both cohorts, 20 common metabolites changed similarly across the season. Metabolites reflective of favorable CV health included an increase in arginine and decreases in hypoxanthine and saturated fatty acids (heptadecanoate, arachidic acid, stearate, and hydroxydecanoate). In contrast, metabolic perturbations of increased lysine and pipecolate, reflective of adverse CV health, were also observed. Adjusting for player position, race, height, and changes in systolic blood pressure, weight, and pulse wave velocity, increased lysine ( ß = 0.018, P = 0.02) and pipecolate ( ß = 0.018, P = 0.02) were associated with increased left ventricular mass index. In addition, increased lysine ( ß = -0.049, P = 0.01) and pipecolate ( ß = -0.052, P = 0.008) were also associated with lower E ' (reduced diastolic function). CONCLUSIONS: ASF athletes seem to develop metabolomic changes reflective of both favorable CV health and early CV maladaptive phenotypes. Whether metabolomics can discriminate early pathologic CV transformations among athletes is a warranted future research direction.

Hypertension and Ventricular-Arterial Uncoupling in Collegiate American Football Athletes.

Background Ventricular-arterial (VA) coupling is defined as the ratio between arterial elastance (EA) and left ventricular elastance (ELV). VA uncoupling, as occurs in hypertensive heart disease, is associated with adverse outcomes. This study sought to determine the relationship between American football (AF)-associated hypertension and VA uncoupling. Methods and Results This was a multicenter, longitudinal, and repeated measures observational study of collegiate AF athletes across 3 years of AF participation. Of 200 freshman athletes initially enrolled, 142 (67 Black [47%]/75 White [53%], 58 linemen [41%]/84 nonlinemen [59%]) were prospectively studied with echocardiography and applanation tonometry. Primary echocardiographic VA coupling outcome measures were EA/ELV and ΔEA/ELV, with increased EA/ELV indicating VA uncoupling. Adjusting for race and player position, AF athletes demonstrated increased EA/ELV (mean [95% CI]Δ, 0.10 [0.04-0.15]; P=0.001) and systolic blood pressure (SBP) (mean [95% CI]Δ, 11.4 [8.3-14.5] mm Hg, P<0.001) over their collegiate AF careers. In combination with longitudinal VA uncoupling, hypertension prevalence (including both stage 1 and 2) increased from 54% at baseline to 77% (44% stage 2) at the end of the study period (P<0.001). In multivariable mixed-effects linear regression analysis, higher SBP (ß=0.021, P=0.02), lower E' (ß=-0.010, P=0.03), and worse global longitudinal strain (ß=0.036, P<0.001) were associated with higher EA/ELV. Increased SBP (ΔSBP, ß=0.029, P=0.02) and worsened global longitudinal strain (Δglobal longitudinal strain, ß=0.045, P<0.001) also predicted increased ΔEA/ELV. Conclusions VA uncoupling is associated with pathologically increased SBP and subclinical impairments in left ventricular systolic function in collegiate AF athletes, indicating a key mechanism underlying maladaptive cardiovascular phenotypes observed in this population. Future studies analyzing whether targeted clinical interventions improve VA coupling and health outcomes are warranted.

Association between race and maladaptive concentric left ventricular hypertrophy in American-style football athletes.

OBJECTIVES: American-style football (ASF) athletes are at risk for the development of concentric left ventricular hypertrophy (C-LVH), an established cardiovascular risk factor in the general population. We sought to address whether black race is associated with acquired C-LVH in collegiate ASF athletes. METHODS: Collegiate ASF athletes from two National Collegiate Athletic Association Division-I programmes were recruited as freshmen between 2014 and 2019 and analysed over 3 years. Demographics (neighbourhood family income) and repeated clinical characteristics and echocardiography were recorded longitudinally at multiple timepoints. A mixed-modelling approach was performed to evaluate acquired C-LVH in black versus white athletes controlling for playing position (linemen (LM) and non-linemen (NLM)), family income, body weight and blood pressure. RESULTS: At baseline, black athletes (N=124) were more often NLM (72% vs 54%, p=0.005) and had lower median neighbourhood family income ($54 119 vs $63 146, p=0.006) compared with white athletes (N=125). While both black and white LM demonstrated similar increases in C-LVH over time, among NLM acquired C-LVH was more common in black versus white athletes (postseason year-1: N=14/89 (16%) vs N=2/68 (3%); postseason year-2: N=9/50 (18%) vs N=2/32 (6%); postseason year-3: N=8/33 (24%) vs N=1/13 (8%), p=0.005 change over time). In stratified models, black race was associated with acquired C-LVH in NLM (OR: 3.70, 95% CI 1.12 to 12.21, p=0.03) and LM was associated with acquired C-LVH in white athletes (OR: 3.40, 95% CI 1.03 to 11.27, p=0.048). CONCLUSIONS: Independent of family income and changes in weight and blood pressure, black race was associated with acquired C-LVH among collegiate ASF NLM and LM was associated with acquired C-LVH in white athletes.

Berry-Derived Polyphenols in Cardiovascular Pathologies: Mechanisms of Disease and the Role of Diet and Sex.

Cardiovascular disease (CVD) prevalence, pathogenesis, and manifestation is differentially influenced by biological sex. Berry polyphenols target several signaling pathways pertinent to CVD development, including inflammation, oxidative stress, and cardiac and vascular remodeling, and there are innate differences in these pathways that also vary by sex. There is limited research systematically investigating sex differences in berry polyphenol effects on these pathways, but there are fundamental findings at this time that suggest a sex-specific effect. This review will detail mechanisms within these pathological pathways, how they differ by sex, and how they may be individually targeted by berry polyphenols in a sex-specific manner. Because of the substantial polyphenolic profile of berries, berry consumption represents a promising interventional tool in the treatment and prevention of CVD in both sexes, but the mechanisms in which they function within each sex may vary.

Inhibition of iNOS augments cutaneous endothelial NO-dependent vasodilation in prehypertensive non-Hispanic Whites and in non-Hispanic Blacks.

We tested the hypothesis that inducible nitric oxide synthase (iNOS) contributes to reduced nitric oxide (NO)-dependent vasodilation in non-Hispanic Blacks and prehypertensive non-Hispanic Whites. Twenty Black and twenty White participants (10 normotensive, 10 prehypertensive per group; n = 40 total) participated in this study. Participants were instrumented with two microdialysis fibers, and each site was randomized as control (lactated Ringer) or iNOS inhibition (0.1 mM 1400W). Laser-Doppler flow probes and local heaters were used to measure skin blood flow and heat the skin to induce vasodilation, respectively. Each site was heated from 33°C to 39°C (rate: 0.1°C/s). Once a plateau was established, 20 mM nitro-l-arginine methyl ester (l-NAME), a nonspecific NOS inhibitor, was infused at each site to quantify NO-dependent vasodilation. At control sites, %NO-dependent vasodilation was reduced in prehypertensive Whites (47 ± 10%NO) and in both normotensive and prehypertensive Blacks (39 ± 9%NO and 28 ± 5%NO, respectively) relative to normotensive Whites (73 ± 8%NO; P < 0.0001 for all comparisons). Compared with respective control sites, iNOS inhibition increased NO-dependent vasodilation in prehypertensive Whites (68 ± 8%NO) and in both normotensive and prehypertensive Blacks (78 ± 8%NO and 55 ± 6%NO, respectively; P < 0.0001 for all comparisons). We failed to find an effect for normotensive Whites (77 ± 7%NO). After iNOS inhibition, %NO-dependent vasodilation was similar between normotensive Whites, prehypertensive Whites, and normotensive Blacks. Inhibition of iNOS increased NO-dependent vasodilation to a lesser extent in prehypertensive Blacks. These data suggest that iNOS contributes to reduced NO-dependent vasodilation in prehypertension and in Black participants.NEW & NOTEWORTHY Inducible nitric oxide synthase (iNOS) is typically upregulated in conditions of increased oxidative stress and may have detrimental effects on the vasculature. Endothelial nitric oxide (NO), which is cardioprotective, is reduced in prehypertensive non-Hispanic Whites and in non-Hispanic Blacks. We found that inhibition of iNOS can increase endothelial NO-dependent vasodilation in prehypertensive White participants and in both normotensive and prehypertensive Black participants.Inducible nitric oxide (NO) synthase (iNOS) can be upregulated under conditions of increased oxidative stress and may have detrimental effects on the vasculature. Endothelial NO, which is cardioprotective, is reduced in prehypertensive non-Hispanic Whites and in non-Hispanic Blacks. We found that inhibition of iNOS can increase endothelial NO-dependent vasodilation in prehypertensive White participants and in both normotensive and prehypertensive Black participants.

Female Sex Hormone Effects on the Vasculature: Considering the Validity of Restricting Study Inclusion to Low-Hormone Phases.

Many studies of vascular function limit the testing of premenopausal female participants to periods when female sex hormones, either endogenous or exogenous, are at their lowest concentration. This practice, when not part of the specific research question, may limit data surrounding the predominant physiological state of premenopausal females and pose a threat to external validity. In this Perspective, we briefly review the literature on the effect of female sex hormones on vascular function and discuss when limiting experimental testing to a certain phase of the menstrual cycle (MC) or oral contraceptive (OC) use may be appropriate. The goal of this Perspective is to open a dialog that may enhance data validity and the overall understanding of vascular function in premenopausal females.

Sensory nerve-mediated and nitric oxide-dependent cutaneous vasodilation in normotensive and prehypertensive non-Hispanic blacks and whites.

The purpose of this study was to investigate the effect of race and subclinical elevations in blood pressure (i.e., prehypertension) on cutaneous sensory nerve-mediated and nitric oxide (NO)-dependent vasodilation. We recruited participants who self-identified as either non-Hispanic black (n = 16) or non-Hispanic white (n = 16). Within each group, participants were subdivided as either normotensive (n = 8 per group) or prehypertensive (n = 8 per group). Each participant was instrumented with four intradermal microdialysis fibers: 1) control (lactated Ringer's), 2) 5% lidocaine (sensory nerve inhibition), 3) 20 mM Nω-nitro-l-arginine methyl ester (l-NAME) (NO synthase inhibition), and 4) lidocaine + l-NAME. Skin blood flow was assessed via laser-Doppler flowmetry, and each site underwent local heating from 33°C to 39°C. At the plateau, 20 mM l-NAME were infused at control and lidocaine sites to quantify NO-dependent vasodilation. Maximal vasodilation was induced via 54 mM sodium nitroprusside and local heating to 43°C. Data are means ± SD. Sensory nerve-mediated cutaneous vasodilation was reduced in prehypertensive non-Hispanic white (34 ± 7%) and both non-Hispanic black groups (normotensive, 20 ± 9%, prehypertensive, 24 ± 15%) relative to normotensive non-Hispanic whites (54 ± 12%). NO-dependent vasodilation was also reduced in prehypertensive non-Hispanic white (41 ± 7%) and both non-Hispanic black groups (normotensive, 44 ± 7%, prehypertensive, 19 ± 7%) relative to normotensive non-Hispanic whites (60 ± 11%). The decrease in NO-dependent vasodilation in prehypertensive non-Hispanic blacks was further reduced relative to all other groups. These data suggest subclinical increases in blood pressure adversely affect sensory-mediated and NO-dependent vasodilation in both non-Hispanic blacks and whites.NEW & NOTEWORTHY Overt hypertension is known to reduce cutaneous sensory nerve-mediated and nitric oxide (NO)-dependent vasodilation, but the effect of subclinical increases in blood pressure (i.e., prehypertension) is unknown. The combined effect of race and prehypertension is also unknown. In this study, we found that prehypertension reduces cutaneous sensory nerve-mediated and NO-dependent vasodilation in both non-Hispanic white and black populations, with the greatest reductions observed in prehypertensive non-Hispanic blacks.

Cutaneous sensory nerve-mediated microvascular vasodilation in normotensive and prehypertensive non-Hispanic Blacks and Whites.

Relative to non-Hispanic Whites, non-Hispanic Blacks are disproportionately affected by elevated blood pressure (BP). It is unknown whether race or subclinical increases in BP affect the ability of cutaneous sensory nerves to induce cutaneous microvascular vasodilation. Sixteen participants who self-identified as non-Hispanic Black (n = 8) or non-Hispanic White (n = 8) were subgrouped as normotensive or prehypertensive. Participants were instrumented with three intradermal microdialysis fibers: (a) control, (b) 1 µM sodium nitroprusside (SNP), an exogenous nitric oxide (NO) donor, and (c) 20 mM NG -nitro-l-arginine methyl ester (L-NAME), a non-selective NO synthase inhibitor. A slow local heating protocol (33-40°C, 0.1°C/min) was used to assess the onset of cutaneous sensory nerve-mediated vasodilation (temperature threshold) and skin blood flow was measured using laser-Doppler flowmetry. At control sites, the temperature threshold occurred at a higher temperature in non-Hispanic Blacks (normotensive: 37.2 ± 0.6°C, prehypertensive: 38.9 ± 0.5°C) compared to non-Hispanic Whites (normotensive: 35.2 ± 0.8°C, prehypertensive: 35.2 ± 0.9°C). L-NAME shifted the temperature threshold higher in non-Hispanic Whites (normotensive: 37.8 ± 0.7°C, prehypertensive: 38.2 ± 0.8°C), but there was no observed effect in non-Hispanic Blacks. SNP did not affect temperature threshold in non-Hispanic Whites, but shifted the temperature threshold lower in non-Hispanic Blacks (normotensive: 34.6 ± 1.2°C, prehypertensive: 34.8 ± 1.1°C). SNP mitigated differences in temperature threshold across all groups. There was no effect found for BP status in either the non-Hispanic Black or non-Hispanic White groups. These data suggest that reduced NO bioavailability affects the ability of cutaneous sensory nerves to induce microvascular vasodilation in young, otherwise healthy non-Hispanic Blacks.

A Hidden Threat: Anomalous Aortic Origins of the Coronary Arteries in Athletes.

PURPOSE OF REVIEW: Anomalous aortic origins of the coronary arteries (AAOCA) are a primary cause of sudden cardiac death in athletes. This review will detail the epidemiology, pathophysiology, and risk stratification of AAOCA, while also highlighting return-to-play considerations for athletes. RECENT FINDINGS: Sport pre-participation cardiovascular screening methods lack sensitivity and specificity in the identification of AAOCA. For the symptomatic athlete, clinicians must maintain a heightened clinical suspicion for AAOCA in order to proceed with appropriate cardiac imaging and functional assessments. Anomalous origin of the left coronary artery with an interarterial course is considered high-risk and requires sport restriction until surgical correction. In contrast, risks associated with anomalous origin of the right coronary artery are controversial, thus management and sports eligibility decisions may incorporate principles of shared-decision making. SUMMARY: Management options for athletes with AAOCA are complex, requiring a comprehensive clinical evaluation. While advances in multimodality cardiovascular imaging and physiologic functional assessments have improved AAOCA risk stratification, best practice treatment strategies for some AAOCA subtypes remain uncertain. As such, clinical management and sport eligibility decisions require an individualized approach. Future prospective data will guide optimization of treatment strategies for athletes with AAOCA.