Effects of a Transoceanic Rowing Challenge on Cardiorespiratory Function and Muscle Fitness.

Ultra-endurance sports and exercise events are becoming increasingly popular for older age groups. We aimed to evaluate changes in cardiac function and physical fitness in males aged 50-60 years who completed a 50-day transoceanic rowing challenge. This case account of four self-selected males included electro- and echo-cardiography (ECG, echo), cardiorespiratory and muscular fitness measures recorded nine months prior to and three weeks after a transatlantic team-rowing challenge. No clinically significant changes to myocardial function were found over the course of the study. The training and race created expected functional changes to left ventricular and atrial function; the former associated with training, the latter likely due to dehydration, both resolving towards baseline within three weeks post-event. From race-start to finish all rowers lost 8.4-15.6 kg of body mass. Absolute cardiorespiratory power and muscular strength were lower three weeks post-race compared to pre-race, but cardiorespiratory exercise economy improved in this same period. A structured program of moderate-vigorous aerobic endurance and muscular training for>6 months, followed by 50-days of transoceanic rowing in older males proved not to cause any observable acute or potential long-term risks to cardiovascular health. Pre-event screening, fitness testing, and appropriate training is recommended, especially in older participants where age itself is an increasingly significant risk factor.

Clinical indications and triaging for adult transthoracic echocardiography: a consensus statement by the British Society of Echocardiography in collaboration with British Heart Valve Society.

Transthoracic echocardiography (TTE) is widely utilised within many aspects of clinical practice, as such the demand placed on echocardiography services is ever increasing. In an attempt to provide incremental value for patients and standardise patient care, the British Society of Echocardiography in collaboration with the British Heart Valve Society have devised updated guidance for the indications and triaging of adult TTE requests for TTE services to implement into clinical practice.

United Kingdom standards for non-invasive cardiac imaging: recommendations from the Imaging Council of the British Cardiovascular Society.

Heart and circulatory diseases affect more than seven million people in the UK. Non-invasive cardiac imaging is a critical element of contemporary cardiology practice. Progressive improvements in technology over the last 20 years have increased diagnostic accuracy in all modalities and led to the incorporation of non-invasive imaging into many standard cardiac clinical care pathways. Cardiac imaging tests are requested by a variety of healthcare practitioners and performed in a range of settings from the most advanced hospitals to local health centres. Imaging is used to detect the presence and consequences of cardiovascular disease, as well as to monitor the response to therapies. The previous UK national imaging strategy statement which brought together all of the non-invasive imaging modalities was published in 2010. The purpose of this document is to collate contemporary standards developed by the modality-specific professional organisations which make up the British Cardiovascular Society Imaging Council, bringing together common and essential recommendations. The development process has been inclusive and iterative. Imaging societies (representing both cardiology and radiology) reviewed and agreed on the initial structure. The final document therefore represents a position, which has been generated inclusively, presents rigorous standards, is applicable to clinical practice and deliverable. This document will be of value to a variety of healthcare professionals including imaging departments, the National Health Service or other organisations, regulatory bodies, commissioners and other purchasers of services, and service users, i.e., patients, and their relatives.

A patient-centred model to quality assure outputs from an echocardiography department: consensus guidance from the British Society of Echocardiography.

Background Quality assurance (QA) of echocardiographic studies is vital to ensure that clinicians can act on findings of high quality to deliver excellent patient care. To date, there is a paucity of published guidance on how to perform this QA. The British Society of Echocardiography (BSE) has previously produced an Echocardiography Quality Framework (EQF) to assist departments with their QA processes. This article expands on the EQF with a structured yet versatile approach on how to analyse echocardiographic departments to ensure high-quality standards are met. In addition, a process is detailed for departments that are seeking to demonstrate to external bodies adherence to a robust QA process. Methods The EQF consists of four domains. These include assessment of Echo Quality (including study acquisition and report generation); Reproducibility & Consistency (including analysis of individual variability when compared to the group and focused clinical audit), Education & Training (for all providers and service users) and Customer & Staff Satisfaction (of both service users and patients/their carers). Examples of what could be done in each of these areas are presented. Furthermore, evidence of participation in each domain is categorised against a red, amber or green rating: with an amber or green rating signifying that a quantifiable level of engagement in that aspect of QA has been achieved. Conclusion The proposed EQF is a powerful tool that focuses the limited time available for departmental QA on areas of practice where a change in patient experience or outcome is most likely to occur.

Low-dose sodium nitrite attenuates myocardial ischemia and vascular ischemia-reperfusion injury in human models.

OBJECTIVES: The aim of this study was to assess the potential benefits of inorganic nitrite in 2 clinical models: stress-induced myocardial ischemia and whole-arm ischemia-reperfusion. BACKGROUND: Inorganic nitrite, traditionally considered a relatively inert metabolite of nitric oxide, may exert vasomodulatory and vasoprotective effects. Despite promising results from animal models, few have shown effectiveness in human model systems, and none have fully translated to the clinical setting. METHODS: In 10 patients with inducible myocardial ischemia, saline and low-dose sodium nitrite (NaNO2) (1.5 µmol/min for 20 min) were administered in a double-blind fashion during dobutamine stress echocardiography, at separate visits and in a random order; long-axis myocardial function was quantified by peak systolic velocity (Vs) and strain rate (SR) responses. In 19 healthy subjects, flow-mediated dilation was assessed before and after whole-arm ischemia-reperfusion; nitrite was given before ischemia or during reperfusion. RESULTS: Comparing saline and nitrite infusions, Vs and SR at peak dobutamine increased in regions exhibiting ischemia (Vs from 9.5 ± 0.5 cm/s to 12.4 ± 0.6 cm/s, SR from -2.0 ± 0.2 s(-1) to -2.8 ± 0.3 s(-1)), whereas they did not change in normally functioning regions (Vs from 12.6 ± 0.4 cm/s to 12.6 ± 0.6 cm/s, SR from -2.6 ± 0.3 s(-1) to -2.3 ± 0.1 s(-1)) (p < 0.001, analysis of variance). With NaNO2, the increment of Vs (normalized for increase in heart rate) increased only in poorly functioning myocardial regions (+122%, p < 0.001). Peak flow-mediated dilation decreased by 43% after ischemia-reperfusion when subjects received only saline (6.8 ± 0.7% vs. 3.9 ± 0.7%, p < 0.01); administration of NaNO2 before ischemia prevented this decrease in flow-mediated dilation (5.9 ± 0.7% vs. 5.2 ± 0.5%, p = NS), whereas administration during reperfusion did not. CONCLUSIONS: Low-dose NaNO2 improves functional responses in ischemic myocardium but has no effect on normal regions. Low-dose NaNO2 protects against vascular ischemia-reperfusion injury only when it is given before the onset of ischemia.

Can isovolumic acceleration be used in clinical practice to estimate ventricular contractile function? Reproducibility and regional variation of a new noninvasive index.

BACKGROUND: Myocardial acceleration during isovolumic contraction (IVA) has been validated as a relatively load-insensitive noninvasive index of contractility. Its feasibility, reproducibility, and variation between segments have not been studied in detail, and thus its utility in clinical practice has not been established. METHODS: We analyzed myocardial velocity loops (median frame rate 182 s(-1)) from 20 young volunteers (10 men, aged 25.7 +/- 2.9 years), 20 patients with type 2 diabetes (14 men, aged 64.1 +/- 8.5 years), and 20 patients with heart failure (17 men, aged 64.6 +/- 7.7 years). Long-axis IVA was measured in all walls at the annulus and in basal and mid-ventricular segments. Intraobserver reproducibility for 1 observer in all subjects and interobserver reproducibility among 3 observers in 10 subjects from each group were assessed. RESULTS: In control subjects, subjects with diabetes, and subjects with heart failure, the feasibility of measuring IVA was 97%, 89%, and 82%, respectively; intraobserver reproducibility was 12%, 18%, and 30%, respectively (pooled coefficients of variation); and mean interobserver reproducibility was 23%, 21%, and 28%, respectively. IVA was lower in the mid-ventricular segments by 24% to 43% compared with the annulus, and IVA was higher in the right than the left ventricle (P < .001). IVA of the medial mitral annulus discriminated those with heart failure from those with diabetes and controls, and had acceptable intraobserver reproducibility across groups (mean coefficient of variation 13%). CONCLUSION: IVA may be used as a research tool if it is measured at the medial mitral annulus, but its clinical applicability is hampered by low reproducibility, especially in patients with impaired left ventricular function in whom it would otherwise be most useful.

Low-dose sodium nitrite vasodilates hypoxic human pulmonary vasculature by a means that is not dependent on a simultaneous elevation in plasma nitrite.

Inorganic nitrite has recently been recognized to possess vascular activity that is enhanced in hypoxia. This has been demonstrated in humans in the forearm vascular bed. In animal models nitrite reduces pulmonary vascular resistance, but its effects upon the pulmonary circulation of humans have not yet been demonstrated. This paradigm is of particular interest mechanistically since the pulmonary vasculature is known to behave differently to the systemic. To investigate, 18 healthy volunteers were studied in a hypoxic chamber (inspired oxygen, 12%) or while breathing room air. Each received an infusion of sodium nitrite (1 micromol/min) or 0.9% saline. Three protocols were performed: nitrite/hypoxia (n = 12), saline/hypoxia (n = 6), and nitrite/normoxia (n = 6). Venous blood was sampled for plasma nitrite, forearm blood flow was measured by strain-gauge plethysmography, and pulmonary arterial pressure was measured by transthoracic echocardiography. Plasma nitrite doubled and clearance kinetics were similar whether nitrite was infused in hypoxia or normoxia. During hypoxia, nitrite increased forearm blood flow (+36%, P < 0.001) and reduced three separate indirect indexes of pulmonary arterial pressure by 16%, 12%, and 17% (P < 0.01). Pulmonary, but not systemic, arterial effects persisted 1 h after stopping the infusion, at a time when plasma nitrite had returned to baseline. No effects were observed during normoxia. Therefore, in hypoxic but not normoxic subjects, sodium nitrite causes arterial and pulmonary vasodilatation. In addition, hypoxia-induced pulmonary vasoconstriction was attenuated for a prolonged period and not dependent on a simultaneous elevation of plasma nitrite. This finding is consistent with the direct extravascular metabolism of nitrite to nitric oxide to effect hypoxia-associated bioactivity.

Blood vessel specific vaso-activity to nitrite under normoxic and hypoxic conditions.

This study uses an organ chamber bioactivity assay to characterise the direct effect of sodium nitrite upon rabbit blood vessels (aorta (Ao), inferior vena cava (IVC) and pulmonary artery (PA)) in a haemoglobin independent/variable oxygen environment. In 95% oxygen constriction to 8g (Ao), 6g (PA) and 4g (IVC) was achieved using 1 microM phenylephrine. The same constriction in 1% oxygen required 3 microM. During 95% oxygen constriction was consistent and sustained for all vessels. However under 1% oxygen PA was quick to constrict but rapidly gave up this tension whereas Ao was slower to constrict but exhibited a more sustained response. Relaxation of each vessel was assessed post constriction using 10 microM sodium nitrite. Results were expressed as a percentage loss in tension compared to the maximum achieved and corrected by controls which received no nitrite. At 95% oxygen PA relaxed greater than Ao (10.04% +/- 2.28% vs. 5.25% +/- 1.51%). IVC response was varied (2.26% +/- 9.43%). At 1% oxygen all vessels relaxed more. However the pattern was reversed with both IVC (14.20% +/- 3.63%) and PA (16.55% +/- 0.93%) relaxing less than Ao (42.20% +/- 5.21%). These results suggest that relatively low concentrations of sodium nitrite can vasodilate blood vessels. This effect is independent of haemoglobin and tissue specific.

The measurement of nitric oxide and its metabolites in biological samples by ozone-based chemiluminescence.

A plethora of publications on techniques and methodologies for measuring nitric oxide (NO) or reaction products of NO (NO metabolites) has served in recent years to complicate and confuse the majority of researchers interested in this field. Here, we provide a practical approach and summarize the key issues and corresponding solutions regarding quantification with the use of ozone-based chemiluminescence, which is the most accurate, sensitive, and widely used NO detection method. We have drawn on the vast experience of leaders in the field to produce this consensus, but the views and implications presented herein represent our own, and we limit our advice to those techniques with which we have direct experience. Hopefully, this guide will allow authors to make more informed decisions regarding NO metabolite measurement methodology, without the need for each subsequent group to rediscover previously observed advantages and pitfalls.

Electrocardiographic evidence for right heart strain in asymptomatic children living in Tibet--a comparative study between Han Chinese and ethnic Tibetans.

OBJECTIVE: To compare ethnic Tibetan children with Han Chinese migrants for signs of right ventricular strain using electrocardiography (ECG) that would suggest chronic hypoxia at altitudes of 3500 to 4500 m above sea level. METHODS: One hundred thirty-five asymptomatic school children aged 7 to 12 years were assessed for height, weight, and blood pressure and underwent a single ECG at 2 centers at 3500 and 4500 m. A questionnaire was given to parents to provide demographic data with relevant medical history. RESULTS: There was a high prevalence of right ventricular strain on ECG for both Tibetan and Han children (33%) with no significant difference between the 2 ethnic groups or sexes. CONCLUSIONS: Other studies showing higher observed rates of symptomatic chronic altitude sickness in Han Chinese children suggest that other extracardiologic factors play a role in the pathogenesis of the disease.