Sublingual Nitroglycerin Research Articles

Blood pressure reduction in hypertensive acute ischemic stroke patients does not affect cerebral blood flow

The effect of blood pressure (BP) reduction on cerebral blood flow (CBF) in acute ischemic stroke is unknown. We measured regional CBF with perfusion-weighted MRI before and after BP treatment in a three-armed non-randomized prospective controlled trial. Treatment arm assignment was based on acute mean arterial pressure (MAP). Patients with (MAP) >120 mmHg (n = 14) were treated with intravenous labetalol and sublingual (SL) nitroglycerin (labetalol group). Those with MAP 100–120 mmHg (n = 17) were treated with SL nitroglycerin (0.3 mg) (‘NTG Group’) and those with baseline MAP<100 mmHg (n = 18) were not treated with antihypertensive drugs (untreated group). Forty-nine patients (18 female, mean age 65.3 ± 12.9 years) were serially imaged. Labetalol reduced MAP by 12.5 (5.7–17.7) mmHg, p = 0.0002. MAP remained stable in the NTG (6.0 (0.4–16, p = 0.3) mmHg and untreated groups (−0.3 (−2.3–7.0, p = 0.2) mmHg. The volume of total hypoperfused tissue (CBF<18 ml/100 g/min) did not increase after labetalol (−1.1 ((−6.5)–(−0.2)) ml, p = 0.1), NTG (0 ((−1.5)–4.5) ml, p = 0.72), or no treatment 0.25 ((−10.1)–4.5) ml, p = 0.87). Antihypertensive therapy, based on presenting BP, in acute stroke patients was not associated with an increased volume of total hypoperfused tissue.

A prospective randomised study comparing intravenous magnesium sulphate and sublingual nitroglycerine spray in attenuating haemodynamic responses to laryngoscopy and intubation

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Laryngoscopy and tracheal Intubation are invariably associated with certain stress responses due to the sympatho-adrenal stimulation. These cardiovascular and neurohumoral alterations may directly affect the physiology and increase the risk. So far, various drugs have been tried but none has been considered ideal for blunting this presser response. We therefore, planned this comparative study to evaluate and compare the efficacy of intravenous magnesium sulphate (30 mg/kg) versus sublingual nitroglycerine spray (0.4 mg/spray) in attenuating the presser response to Laryngoscopy and Tracheal Intubation.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; Fifty patients, aged 15–50 years, scheduled for elective surgery under general anaesthesia, were randomly assigned to one of the two groups of 25 each, Group A (magnesium group) and Group B&lt;strong&gt; &lt;/strong&gt;(nitroglycerine group). Study drug was given 90-120 seconds before tracheal intubation. Heart rate, Systolic blood pressure and Rate pressure product were recorded at different intervals after administering the study drug till 3 minutes after intubation.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Mean heart rate was significantly higher from the baseline at all times after administering the study drug in both the groups. Increase in systolic blood pressure as a presser response was limited to 7.25% in Group A and 5.83% in Group B from the baseline after tracheal intubation. There was relative hypotension after administration of the study drug in both the groups.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Intravenous magnesium or sublingual nitroglycerine pre-treatment is found to be effective in attenuating the presser response to laryngoscopy and intubation. These drugs may lead to rise in HR but it is transient and dose dependent. However, both the drugs can significantly control the hypertensive response after laryngoscopy and intubation.&lt;/p&gt;&lt;p class="abstract"&gt; &lt;/p&gt;

Chronic Supplementation With a Mitochondrial Antioxidant (MitoQ) Improves Vascular Function in Healthy Older Adults.

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02597023.

Wellens’ syndrome: a pattern to remember

Electrocardiographic changes in asymptomatic individuals may be a diagnostic challenge. The knowledge and early identification of these patterns and their correct association with clinical picture shall have an urgent and...

Mitochondrial‐Targeted Antioxidant (MitoQ) Improves Vascular Function in Healthy Late Middle‐Aged and Older Adults

Excess reactive oxygen species production by mitochondria (mtROS) is a key mechanism of vascular dysfunction with aging. Our laboratory has shown that supplementation with the mitochondrial‐targeted antioxidant MitoQ improves vascular endothelial function by reducing mtROS and ameliorates arterial stiffening in old mice, but the effects in humans are unknown. Here we sought to translate our preclinical findings to humans, while also determining the safety and efficacy of MitoQ. Twenty healthy late middle‐aged and older adults (60–79 years) with impaired endothelial function (baseline brachial artery flow‐mediated dilation [FMD] &lt;6%) underwent six weeks of oral supplementation with MitoQ (20 mg/day) or placebo in a randomized, placebo‐controlled, double‐blind, crossover design study. MitoQ was well tolerated, and no treatment‐related serious adverse events occurred. Plasma MitoQ concentrations were higher after the treatment vs. placebo period (P&lt;0.05). Brachial artery FMD was 42% higher after MitoQ vs. placebo (P&lt;0.05); this improvement was associated with complete amelioration of tonic mtROS‐related suppression of endothelial function (assessed as the increase in FMD with acute 160 mg dose of MitoQ, n=9, P&lt;0.05). Aortic stiffness (carotid‐femoral pulse wave velocity [PWV]) was lower after MitoQ vs. placebo (P&lt;0.05) in participants with elevated baseline levels (carotid‐femoral PWV &gt;7.60 m/s, n=11). Plasma oxidized low‐density lipoprotein, a marker of oxidative stress, also was lower after MitoQ vs. placebo (P&lt;0.05), whereas participant characteristics, endothelium‐independent dilation (sublingual nitroglycerin) and circulating markers of inflammation were not different (all P&gt;0.1). These findings in humans support earlier preclinical observations and suggest that MitoQ and other therapeutic strategies targeting mtROS may hold promise for treating age‐related vascular dysfunction.Support or Funding InformationClinicaltrials.gov Identifier: NCT02597023Funding: Supported by NIH R21 AG049451, T32 AG000279, F32 AG053009, Colorado CTSA UL1 TR001082 and an industry contract with MitoQ Limited.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Associations of sex, age and adiposity in endothelium-independent dilation in children

Objective: To examine the association of age, sex, and obesity status on endothelial-independent dilation (EID) among children and adolescents. Study design: This study examined 264 children (143 males) between 8 to 18 years old (mean ± SD: age = 14.3 ± 2.7 years). Endothelial-independent dilation was assessed via ultrasound imaging of the brachial artery following administration of 0.3 milligrams of sublingual nitroglycerin. A one-way analysis of variance with Bonferroni post hoc comparisons assessed sex-differences in percent peak EID dilation (EID%-peak) and EID area under the curve (EID%-AUC), while analysis of covariance (ANCOVA) adjusted for race, age, body mass index percentile (BMI-percentile), and brachial artery diameter. Multiple linear regression evaluated the association of sex, age, BMI-percentile, percent body fat (%BF), and brachial artery diameter on EID. Results: Prior to adjustment, EID%-peak was significantly higher among females than males (mean ± SE: 26.9 ± 0.5% versus 22.9 ± 0.6%, p < 0.001, respectively); similar findings for EID%-AUC (4214% ± 105%·s versus 3398% ± 97%·s, p < 0.001) were observed. After adjusting for covariates, EID%-AUC remained consistent (p = 0.03) while EID%-peak was not significantly different between sexes (p = 0.21). EID%-peak was significantly higher among normal weight compared to obese participants (p = 0.04), while no differences were observed between obesity status after adjustment for brachial artery diameter (p = 0.64). Both unadjusted (p = 0.16) and adjusted EID%-AUC (p = 0.24) was not significantly different between obesity status. BMI-percentile was not associated with EID%-peak (p = 0.76) or EID%-AUC (p = 0.30). Additionally, %BF was not associated with EID%-peak (p = 0.56) or EID%-AUC (p = 0.15). After adjusting for brachial artery diameter, BMI-percentile, and age, males had lower EID%-AUC (p = 0.03) and lower but not significant EID%-peak (p = 0.21). Significance: Vascular smooth muscle function was significantly lower among male children and adolescents, which is suggestive that impaired EID and increased cardiovascular disease risk among males may begin in childhood. Interestingly, obesity status and BMI-percentile was not associated with EID in children and adolescents after adjusting for brachial artery diameter.

TCTAP C-050 Left main Bifurcation Intervention Combined with Reverse Guidewire Technique and Modify DK-CRUSH Technique

### Patient Initials or Identifier Number PSL ### Relevant Clinical History and Physical Exam A 60-year male for chest discomfort ongoing 50 meters, could be relieved by rest or sublingual nitroglycerin for 3-5 minutes. The coronary risk factor was hypertension, hyperlipidemia current smoking.PE

Effect of organic and inorganic nitrates on cerebrovascular pulsatile power transmission in patients with heart failure and preserved ejection fraction

Objective: Increased penetration of pulsatile power to the brain has been implicated in the pathogenesis of age-related cognitive dysfunction and dementia, a common comorbidity in patients with heart failure and preserved ejection fraction (HFpEF). However, there is a lack of knowledge on the effects of organic and inorganic nitrates administration in this population on the power carried by pressure and flow waves traveling through the proximal aorta and penetrating the carotid artery into the brain microvasculature. Approach: We assessed aortic and carotid hemodynamics non-invasively in two sub-studies: (1) at baseline and after administration of 0.4 mg of sublingual nitroglycerine (an organic nitrate; n = 26); and (2) in a randomized controlled trial of placebo (PB) versus inorganic nitrate administration (beetroot-juice (BR), 12.9 mmol NO3; n = 16). Main results: Wave and hydraulic power analysis demonstrated that NTG increased total hydraulic power (from 5.68% at baseline to 8.62%, P = 0.001) and energy penetration (from 8.69% to 11.63%; P = 0.01) from the aorta to the carotid, while inorganic nitrate administration did not induce significant changes in aortic and carotid wave power (power: 5.49%PB versus 6.25%BR, P = 0.49; energy: 8.89%PB versus 10.65%BR, P = 0.27). Significance: Organic nitrates, but not inorganic nitrates, increase the amount of hydraulic energy transmitted into the carotid artery in subjects with HFpEF. These findings may have implications for the adverse effect profiles of these agents (such as the differential incidence of headaches) and for the pulsatile hemodynamic stress of the brain microvasculature in this patient population.

Regular Aerobic, Resistance, and Cross-Training Exercise Prevents Reduced Vascular Function Following a High Sugar or High Fat Mixed Meal in Young Healthy Adults.

The postprandial state can negatively influence flow mediated dilation (FMD), a predictor of atherosclerosis and cardiovascular disease. This investigation was designed to determine the effect of regular aerobic and/or resistance exercise on postprandial FMD after a high sugar or high fat mixed meal. Forty-five healthy participants were recruited from one of four groups: lean sedentary (SED), runners, weight lifters, and cross-trainers. Participants were randomly crossed over to a high sugar meal (HSM) and a high fat mixed meal (HFMM; both fat and carbohydrate). Pre-and postprandial endothelial function was assessed for both meals using brachial artery FMD. Plasma lipids, insulin, glucose, hs-CRP, and SOD were also measured with both meals. Endothelium-independent dilation was determined via sublingual nitroglycerin. Brachial artery FMD was reduced in SED following the HSM (9.9 ± 0.9% at baseline, peak reduction at 60 min 6.5 ± 1.0%) and the HFMM (9.4 ± 0.9% at baseline, peak reduction at 120 min 5.9 ± 1.2%; P < 0.05 for both, Mean ± SEM). There was no change in FMD after either HSM or HFMM in runners, weight lifters, and cross-trainers. Post-prandial increases in blood glucose, insulin and triglycerides were less pronounced in the exercisers compared to SED. In addition, exercisers presented lower baseline plasma hs-CRP and higher SOD activity. Nitroglycerin responses were similar among groups. These results suggest that endothelial function is reduced in sedentary adults after a HSM or HFMM, but not in regular aerobic or resistance exercisers. This response may be due to favorable postprandial metabolic responses or lower postprandial levels of inflammation and oxidative stress. These findings may help to explain the cardioprotective effect of exercise.

Flow-mediated dilatation to relieve puncture-induced radial artery spasm: A pilot study.

Puncture-induced radial artery spasm (RAS) may extend the duration of coronary an-giography (CAG) or cause transradial access failure. Flow-mediated dilatation (FMD), a widely-used noninvasive approach for assessing endothelial function, was reported to remove the entrapped radial sheath after percutaneous coronary intervention. Herein, the efficacy and safety of FMD in treating puncture-induced RAS before transradial CAG was investigated. Ninety patients with puncture-induced RAS were randomized in a 1:1:1 ratio into three groups: FMD group was immediately treated with blockage of brachial artery blood for 5 min using a sphygmomanometric cuff and then rapid relief; nitroglycerin (NTG) group was administered with 0.5 mg sublingual NTG instantly; and the no-therapy group was treated with a wait-and-watch strategy. The time of radial pulse recovery, and regional and systemic complications were recorded. The rate of radial pulse recovery within 30 min in FMD group was significantly higher than that in no-therapy group (97% vs. 73%, p = 0.026). The median time to return of radial pulse in FMD group and NTG group was significantly shorter than that in no-therapy group (7 [6.5-9] min vs. 15 [12-18] min, 8 [7-9] min vs. 15 [12-18] min, respectively; both p < 0.001). Headache and decreased blood pressure were more prevalent in NTG group than those in FMD and no-therapy groups. FMD is a feasible, noninvasive and nonpharmacological approach to relieve RAS and facilitate radial artery cannulation after an initial failed attempt. (Cardiol J 2018; 25, 1: 1-6).

Effect of Kuanxiong Aerosol () on Patients with Angina Pectoris: A Non-inferiority Multi-center Randomized Controlled Trial.

To evaluate the effect and safety of Kuanxiong Aerosol (, KA) on patients with angina pectoris. Block randomization was performed to randomly allocate 750 patients into KA (376 cases) and control groups (374 cases). During an angina attack, the KA group received 3 consecutive sublingual sprays of KA (0.6 mL per spray). The control group received 1 sublingual nitroglycerin tablet (NT, 0.5 mg/tablet). Log-rank tests and Kaplan-Meier estimations were used to estimate the angina remission rates at 6 time-points after treatment (1, 2, 3, 4, 5, and >5 min). Logistic regression analysis was performed to observe the factors inflfluencing the rate of effective angina remission, and the remission rates and incidences of adverse reactions were compared for different Canadian Cardiovascular Society (CCS) classes of angina. The 5-min remission rates in the KA and control groups were not signifificantly different (94.41% vs. 90.64%, P>0.05). The angina CCS class signifificantly inflfluenced the rate of remission (95% confidence interval = 0.483-0.740, P<0.01). In the CCS subgroup analysis, the 3-and 5-min remission rates for KA and NT were similar in the CCSII and III subgroups (P>0.05), while they were signifificantly better for KA in the CCSI and II subgroups (P<0.05 or P<0.01). Furthermore, the incidence of adverse reactions was signifificantly lower in the KA group than in the control group for the CCSII and III subgroups (9.29% vs. 26.22%, 10.13% vs. 20.88%, P<0.05 or P<0.01). KA is not inferior to NT in the remission of angina. Furthermore, in CCSII and III patients, KA is superior to NT, with a lower incidence of adverse reactions. (Registration No. ChiCTRIPR-15007204).

Comparative Study of Intravenous Lignocaine and Sublingual Nitroglycerine to Attenuate Stress Response to Laryngoscopy

Comparative Study of Intravenous Lignocaine and Sublingual Nitroglycerine to Attenuate Stress Response to Laryngoscopy

Effects of Sublingual Glyceryl Trinitrate Administration on the Quality of Preprocedure CT Angiography Performed to Plan Prostate Artery Embolization

PurposeTo determine the effects of sublingual glyceryl trinitrate (GTN) on the quality of planning computed tomography (CT) angiography performed prior to prostate artery embolization (PAE). Materials and MethodsA retrospective cohort study was performed on patients who had previously undergone CT angiography before a procedure for PAE at our institution. Early CT angiography studies for PAE at our single center had initially been performed without GTN. These were compared to subsequent CT angiography studies that had been performed with GTN, after a previously implemented change in practice. Prostate arteries were examined by 2 blinded observers for peak enhancement (Hounsfield units [HU]) and lumen diameter. In addition, assessors’ interpretation of the prostate artery origin from CT angiography was compared with the true anatomy demonstrated at the time of procedure. ResultsA total of 16 patients, corresponding to 32 prostate arteries, were examined on CT angiography. Mean diameter of the prostate artery was found to be significantly greater in those receiving GTN (2.2 mm vs. 1.6 mm, P < .001). Peak prostate artery enhancement was also greater in the GTN group (218 HU vs 173 HU, P = 0.042). Observers correctly identified the prostate artery origin more frequently in the GTN group; however, this difference was not statistically significant (56% vs 25%, odds ratio = 3.9, P = .149). ConclusionsThe administration of sublingual GTN immediately prior to CT angiography is associated with a significant increase in prostate artery diameter and peak opacification. This was not associated with a statistically significant increase in the ability of observers to correctly identify the origin of the prostate artery.

In-use Stability Study of Phloroglucinol and Nitroglycerin Sublingual Tablets Using Simulation Design after Opening of their Containers

Expiration date of pharmaceuticals is established based on stability studies on the products. However it does not guarantee stability of pharmaceuticals once their containers are open. In particular pharmaceuticals stored in multi-dose container or the ones which require protection from moisture (e.g. sublingual tablets, effervescent tablets and dispersible tablets) need information on in-use stability after opening of their containers to maintain their safety, efficacy, and quality. It helps consumers to take pharmaceuticals safely. In order to study in-use stability of pharmaceuticals after opening of their containers, Phloroglucinol sublingual tablets and Nitroglycerin sublingual tablets which are sensitive to moisture or humidity were selected. Test methods were developed referring to the applicable EMA guideline, including withdrawal method to consider actual use of pharmaceuticals. The appearance, disintegration and potency of the Phloroglucinol sublingual tablets were evaluated at 1, 3 and 6 month after opening of containers. During 6 months, no difference in appearance and disintegration was found in different 3 lots. However, the potency of active ingredient was decreased gradually during 6 months and the results of 3 lots were 93.4%, 94.1% and 94.2%, respectively, which were out of in-house specification range (95.0~105.0%) of test product. In-use stability of Nitroglycerin sublingual tablets was also evaluated on appearance, disintegration, impurity and potency at 0.5, 1, 2, 3 and 6 month after opening of containers. During 6 months, no significant difference in appearance, disintegration and impurity were found in different 3 lots. However, the potency of active ingredient was decreased gradually during 6 months and the results of 3 lots was 82.1%, 83.2% and 84.1%, respectively, even though they were remained within the KP specification range (80.0~120.0%) of test product. Study results suggest product quality of sublingual tablets can be affected by opening of their containers. For safe and effective use of pharmaceuticals, we recommend the Phloroglucinol sublingual tablets and Nitroglycerin sublingual tablets be stored under the minimized moisture effect and used within 6 months after opening of their containers

Cardiac and haemodynamic influence on carotid artery longitudinal wall motion.

What is the central question of this study? Carotid artery longitudinal wall motion (CALM) is a bidirectional forward and backward motion of the arterial wall; however, there is no evidence in humans for what controls CALM despite proposals for pulse pressure, left ventricular motion and shear rate. What is the main finding and its importance? Carotid artery longitudinal wall motion responses were heterogeneous when manipulating sympathetic activation and endothelium-independent vasodilatation, leading to non-significant group responses. However, individual CALM responses were associated with left ventricular rotation and shear rate. These findings are important when interpreting changes in CALM in humans with acute or chronic experimental designs. Carotid artery longitudinal wall motion (CALM) has recently attracted interest as an indicator of arterial health; however, the regulation of CALM is poorly understood. We conducted a series of studies aimed at manipulating pulse pressure (PP), left ventricular (LV) motion and carotid shear rate, which have been previously suggested to regulate various components of CALM pattern and magnitude. To determine the regulatory influences on CALM, 15 healthy men (22±2years old) were exposed to three acute interventions: the serial subtraction test (SST); the cold pressor test (CPT); and exposure to sublingual nitroglycerine (NTG). The SST elicited increases in PP (P<0.01), apical LV rotation (P<0.01) and carotid shear rate (P<0.01), with no changes in CALM (P>0.05). Likewise, the CPT elicited increases in PP (P=0.01), basal LV rotation (P=0.04) and carotid shear rate (P=0.01), with no changes in CALM (P>0.05). Conversely, exposure to NTG elicited no change in PP (P=0.22), basal (P=0.65) or apical LV rotation (P=0.45), but did decrease carotid shear rate (P<0.01), without altering CALM (P>0.05). Considerable individual variability in CALM responses prompted further analyses where all three interventions were pooled for change scores. Changes in LV basal rotation were related to changes in systolic retrograde CALM (B=-0.025, P=0.03), whereas changes in carotid shear rate were related to changes in diastolic CALM displacement (B=0.0009, P=0.01). The interventions were underpinned by relationships between CALM and both LV basal rotation and local shear rate at the individual level, indicating that cardiac and haemodynamic factors may influence CALM in humans.

Acute oral tetrahydrobiopterin administration ameliorates endothelial dysfunction in systemic sclerosis

Systemic sclerosis (SSc) is a rare, autoimmune disease characterised by endothelial dysfunction, which is associated with peripheral vasculopathy, such as digital ulcers (DU). We sought to determine if acute oral administration of tetrahydrobiopterin (BH4), an essential cofactor for endothelial nitric oxide synthase, would augment endothelial function in patients with SSc. Twelve SSc patients, of whom a majority had a history of DU, were studied 5 hours after oral BH4 administration (10 mg/kg body mass) or placebo on separate days using controlled, counterbalanced, double-blind, crossover experimental design. There were no differences in blood markers of oxidative stress and brachial artery blood pressure, diameter, blood velocity, shear rate, or blood flow at rest between placebo and BH4 (p>0.05). Whereas, after a 5 minute suprasystolic forearm cuff occlusion, brachial artery peak reactive hyperemia (placebo: 313±30 vs. BH4: 347±37 ml/min, p<0.05) and flow-mediated dilation (FMD) (placebo: 3.0±0.8 vs. BH4: 4.8±0.8%, p<0.05) were significantly higher after acute BH4 administration, indicating an improvement in endothelial function. To determine if the vasodilatory effects of BH4 were specific to the vascular endothelium, brachial artery blood flow and vasodilation in response to sublingual nitroglycerin were assessed, and were found to be unaffected by BH4 (p>0.05). These findings indicate that acute BH4 administration ameliorates endothelial dysfunction in patients with SSc. Given that endothelial dysfunction is known to be associated with DU in SSc patients, this study provides a proof-of-concept for the potential therapeutic benefits of BH4 in the prevention or treatment of DU in this population.

Systemic glyceryl trinitrate reduces anal sphincter tone: is there a therapeutic indication?

Nitric oxide (NO) has diverse roles as a biological messenger. [1] Topically applied nitrate donors cause relaxation of the internal anal sphincter (IAS) and facilitate healing of anal fissures [2,3]. Systemic nitrates are commonly used for the treatment of ischaemic heart disease, yet the effects of systemically administered nitrates on the smooth muscle of the IAS are unknown. Our aim was to test the hypothesis that systemically administered nitrates at a normal dose, cause inhibition of anal sphincter activity. With fully informed consent, anal manometry was performed on nine volunteers. Maximum and mean anal resting pressure (representing the IAS), maximum squeeze pressure (representing the external anal sphincter), heart rate and blood pressure were measured, before and after administration of a normal 400μg dose of sublingual glyceryl trinitrate spray. Data are expressed as mean (± standard error of the mean (SEM)). In four females and five males ranging from 19 to 50years of age, administration of GTN resulted in a significant reduction in systolic blood pressure from 138 ± 5 to 127 ± 4mmHg, P<0.01. Mean resting pressure, over 5min, was significantly reduced from 70 ± 10 to 62 ± 10mmHg P<0.05. The maximum resting pressure was also significantly reduced from 109 ± 12 to 86 ± 10mmHg P=0.04. Maximum squeeze pressure, heart rate and diastolic blood pressure were not significantly reduced. Systemic nitrates significantly inhibit internal anal sphincter function.

A pragmatic group sequential, placebo-controlled, randomised trial to determine the effectiveness of glyceryl trinitrate for retained placenta (GOT-IT): a study protocol

IntroductionA retained placenta is diagnosed when the placenta is not delivered following delivery of the baby. It is a major cause of postpartum haemorrhage and treated by the operative procedure...

The effect of pre-procedure sublingual nitroglycerin on radial artery diameter and Allen's test outcome - Relevance to transradial catheterization.

The radial artery is increasingly used for cardiac procedures, but is a relatively small vessel that is prone to spasm when instrumented. Intra-arterial nitroglycerine has been shown to reduce radial spasm but first requires arterial access. We investigated the effect of pre-procedure sublingual nitroglycerin (NTG) on the diameter of the radial artery in a large cohort of patients. 305 subjects underwent ultrasound measurement of their radial and ulnar arteries in both arms before and after the administration of 800μg of sublingual NTG. The Allen's test was also performed in the subjects prior to and after NTG. Radial artery diameter in this Caucasian study group is larger than that reported for other populations. The administration of sublingual NTG significantly increased the size of the right radial artery from 2.88±0.36mm to 3.36±0.40mm in men and from 2.23±0.37 up to 2.74±0.36mm in women. There were also significant increases in left radial, right and left ulnar artery diameters in males and females with NTG. There was no significant effect of NTG on blood pressure. In all patients with an unfavourable Allen's test, retesting following sublingual NTG resulted in transition to a favourable Allen's. Caucasian populations have larger calibre radial arteries compared to other geographic areas. Sublingual NTG is effective at dilating the radial artery in both men and women. This may make radial artery puncture and cannulation less challenging and should be considered in all patients in the absence of contraindications. The results of Allen's testing are dynamic and its usefulness for screening prior to transradial access is undetermined.

Clinical Study of Plasma Lipocalin-2 and Endothelial Function

Recent animal studies suggested that lipocalin-2 plays a key role in the development of hypertension, atherosclerosis and endothelial dysfunction. Lipocalin-2 knockout mice are resistant to the harmful effects of high fat diet and do not develop hypertension or atherosclerosis. We therefore hypothesised that lipocalin-2 is also related to endothelial function in man. We measured plasma lipocalin-2 concentration and brachial artery flow-mediated dilatation (FMD) in 245 subjects (201 men, 44 women; mean age±SD, 68±9 y), of whom 151 had hypertension, 80 had diabetes mellitus and 240 were on lipid lowering therapy. Lipocalin-2 was measured using a highly-specific ELISA, with intra- and interassay coefficients of variation of 3.8-6.0% and 3.1–5.2% respectively. Brachial artery diameter and flow velocity were measured using a 7.5MHz ultrasound probe. Scans were taken at baseline, 5 minutes after tourniquet inflation and after sublingual glyceryl trinitrate spray. The percentage change in brachial artery diameter following reactive hyperaemia was calculated. The coefficient of variation of FMD determination was 5%. The median (IQR) plasma lipocalin-2 concentration was 50 (29-75) ng/mL. There was no sex difference. Plasma lipocalin-2 level correlated with serum creatinine (ρ=0.23, p<0.001) but not FMD (ρ=0.005, p=0.94). Instead, FMD decreased with age (ρ=-0.14, p=0.03). It is also lower in individuals with diabetes (p=0.044). Endothelial function decreases with age and diabetes, but is unrelated to plasma lipocalin-2 level. This suggests that plasma lipocalin-2 level is not a major determinant of endothelial function. However, plasma lipocalin-2 is a marker for renal dysfunction.