Early subclinical increase in pulmonary water content in athletes performing sustained heavy exercise at sea level: ultrasound lung comet-tail evidence

Sex differences in exercise-induced arterial hypoxemia and pulmonary edema following high-intensity exercise in highly trained endurance athletes

This study investigated sex differences in the development of pulmonary edema and exercise-induced arterial hypoxemia (EIAH) in well-trained endurance athletes during near-maximal exercise in a real-world setting. Twenty participants (10M vs. 10F; V̇O2peak: 69.3 (8.8) vs. 50.7 (4.1) ml∙kg-1∙min-1) underwent a maximal incremental treadmill test (visit 1) and a time trial on a steep trail (~2.5 km, ~800 m elevation gain) in North Vancouver (visit 2). Pulmonary edema was evaluated using handheld lung ultrasound ~10-15 min post-exercise and oxygen saturation (SpO2) was monitored using finger pulse oximetry. Males completed the time trial significantly faster than females (M: 31.5 (6.5) vs. F: 40.4 (7.5) min, p = 0.006), while females sustained a higher percentage of their visit 1 heart rate (M: 94 (1) vs. F: 96 (1) %max, p = 0.02). All participants developed EIAH, with no sex differences in end-exercise SpO2 (M: 89 (4) % vs. F: 90 (3) %, respectively, p = 0.35). There was no evidence of pulmonary edema, assessed through ultrasound b-line scores, with no differences between sexes (M: 0.3 (1.0) vs. F: 0.5 (1.5), respectively, p = 0.60). Pulmonary edema is an unlikely contributor to EIAH in endurance athletes performing near-maximal time trial exercise in a real-world setting.

Transient changes in L-arginine, asymmetric and symmetric dimethyl arginine in triathletes following Norseman Xtreme Triathlon

Arterial vasodilation is dependent on nitric oxide synthesized from L-arginine by endothelial nitric oxide synthase. Triathletes are reported to display altered serum concentrations of nitric oxide metabolites such as L-arginine, asymmetric dimethyl arginine (ADMA) and symmetric dimethyl arginine (SDMA) shortly after completing long-distance triathlon races. In other populations, similar changes to nitric oxide metabolites are established risk markers of cardiovascular disease. The objective of this study was to assess serum concentrations of metabolites for endothelial nitric oxide synthesis in triathletes one week following a long-distance triathlon race. In this prospective observational study, we used high-performance liquid chromatography to measure circulating concentrations of L-arginine, ADMA, and SDMA in triathletes. Venous blood samples were collected before, immediately after, day one, and one week following the triathlon race. Serum concentrations and L-arginine/ADMA ratio were determined for each time-point and compared to baseline. L-arginine/ADMA ratio was reduced on day one (147 ± 32 vs 163 ± 40, p < 0.02). ADMA was reduced immediately after and increased at day one and remained elevated at one week (0.29 ± 0.05 μM, p < 0.001, 0.44 ± 0.08 μM, p < 0.001 and 0.42 ± 0.07 μM, p = 0.04, respectively vs 0.40 ± 0.05 μM). SDMA was increased at all time-points when compared to baseline (0.48 ± 0.10 μM, p < 0.001, 0.53 ± 0.11 μM, p < 0.001 and 0.42 ± 0.08 μM, p = 0.048 vs 0.38 ± 0.05 μM). L-arginine was only decreased immediately after (46.0 ± 9.3 μM vs. 64.6 ± 16.1 μM, p < 0.001). Long-distance triathlon racing induces altered levels of metabolites for endothelial nitric oxide production that mostly normalizes within one week following racing. The clinical relevance of these transient changes has yet to be elucidated in the athletic population.

Effect of Ultramarathon Trail Running at Sea Level and Altitude on Alveolar-Capillary Function and Lung Diffusion

INTRODUCTION

Endurance exercise at altitude can increase cardiac output and pulmonary vascular pressure to levels that may exceed the stress tolerability of the alveolar-capillary unit. This study examined the effect of ultramarathon trail racing at different altitudes (ranging from <1000 m to between 1500 and 2700 m) on alveolar-capillary recruitment and lung diffusion.

METHODS

Cardiac and lung function were examined before and after an ultramarathon in 67 runners (age: 41 ± 9 yr, body mass index: 23 ± 2 kg·m -2 , 10 females), and following 12-24 h of recovery in a subset ( n = 27). Cardiac biomarkers (cTnI and BNP) were assessed from whole blood, whereas lung fluid accumulation (comet tails), stroke volume (SV), and cardiac output ( Q ) were quantified via echocardiography. Lung diffusing capacity for carbon monoxide (DLco) and its components, alveolar membrane conductance (Dm) and capillary blood volume (Vc), were determined via a single-breath method at rest and during three stages of submaximal semirecumbent cycling (20, 30, and 40 W).

RESULTS

Average race time was 25 ± 12 h. From pre- to post-race, there was an increase in cardiac biomarkers (cTnI: 0.04 ± 0.02 vs 0.13 ± 0.03 ng·mL -1 , BNP: 20 ± 2 vs 112 ± 21 pg·mL -1 ; P < 0.01) and lung comet tails (2 ± 1 vs 7 ± 6, P < 0.01), a decrease in resting and exercise SV (76 ± 2 vs 69 ± 2 mL, 40 W: 93 ± 2 vs 88 ± 2 mL; P < 0.01), and an elevation in Q at rest (4.1 ± 0.1 vs 4.6 ± 0.2 L·min -1 , P < 0.01; 40 W: 7.3 ± 0.2 vs 7.4 ± 0.3 L·min -1 , P = 0.899). Resting DLco and Vc decreased after the race ( P < 0.01), whereas Dm was unchanged ( P = 0.465); however, during the three stages of exercise, DLco, Vc, and Dm were all reduced from pre- to post-race (40 W: 36.3 ± 0.9 vs 33.0 ± 0.8 mL·min -1 ·mm Hg -1 , 83 ± 3 vs 73 ± 2 mL, 186 ± 6 vs 170 ± 7 mL·min -1 ·mm Hg -1 , respectively; P < 0.01). When corrected for alveolar volume and Q , DLco decreased from pre- to post-race ( P < 0.01), and changes in DLco were similar for all ultramarathon events ( P > 0.05).

CONCLUSIONS

Competing in an ultramarathon leads to a transient increase in cardiac injury biomarkers, mild lung-fluid accumulation, and impairments in lung diffusion. Reductions in DLco are predominantly caused by a reduced Vc and possible pulmonary capillary de-recruitment at rest. However, impairments in alveolar-capillary recruitment and Dm both contribute to a fall in exertional DLco following an ultramarathon. Perturbations in lung diffusion were evident across a range of event distances and varying environmental exposures.

Telemedicine in Sports under Extreme Conditions: Data Transmission, Remote Medical Consultations, and Diagnostic Imaging

Telemedical technologies provide significant benefits in sports for performance monitoring and early recognition of many medical issues, especially when sports are practised outside a regulated playing field, where participants are exposed to rapidly changing environmental conditions or specialised medical assistance is unavailable. We provide a review of the medical literature on the use of telemedicine in adventure and extreme sports. Out of 2715 unique sport citations from 4 scientific databases 16 papers met the criteria, which included all research papers exploring the use of telemedicine for monitoring performance and health status in extreme environments. Their quality was assessed by a double-anonymised review with a specifically designed four-item scoring system. Telemedicine was used in high-mountain sports (37.5%; n = 6), winter sports (18.7%; n = 3), water sports (25%; n = 4), and long-distance land sports (18.7%; n = 3). Telemedicine was used for data transfer, teleconsulting, and the execution of remote-controlled procedures, including imaging diagnostics. Telemedical technologies were also used to diagnose and treat sport-related and environmentally impacted injuries, including emergencies in three extreme conditions: high mountains, ultraendurance activities, and in/under the water. By highlighting sport-specific movement patterns or physiological and pathological responses in extreme climatic conditions and environments, telemedicine may result in better preparation and development of strategies for an in-depth understanding of the stress of the metabolic, cardiorespiratory, biomechanical, or neuromuscular system, potentially resulting in performance improvement and injury prevention.

Exercise-induced myocardial edema in master triathletes: Insights from cardiovascular magnetic resonance imaging

Background

Strenuous exercise has been associated with functional and structural cardiac changes due to local and systemic inflammatory responses, reflecting oxidative, metabolic, hormonal, and thermal stress, even in healthy individuals. We aimed to assess changes in myocardial structure and function using cardiovascular magnetic resonance (CMR) imaging in master triathletes early after a full-distance Ironman Triathlon race.

Materials and methods

Ten master triathletes (age 45 ± 8 years) underwent CMR within 3 h after a full-distance Ironman Triathlon race (3.8 km swimming, 180 km cycling, and 42.2 km running) completed with a mean time of 12 ± 1 h. All the triathletes had a 30-day follow-up CMR. Cine balanced steady-state free precession, T2-short tau inversion recovery (STIR), tagging, and late gadolinium enhancement (LGE) imaging sequences were performed on a 1.5-T MR scanner. Myocardial edema was defined as a region with increased T2 signal intensity (SI) of at least two SDs above the mean of the normal myocardium. The extent of myocardial edema was expressed as the percentage of left ventricular (LV) mass. Analysis of LV strain and torsion by tissue tagging included the assessment of radial, longitudinal, and circumferential peak systolic strain, rotation, and twist.

Results

Compared with postrace, biventricular volumes, ejection fraction, and LV mass index remained unchanged at 30-day follow-up. Global T2 SI was significantly higher in the postrace CMR (postrace 10.5 ± 6% vs. follow-up 3.9 ± 3.8%, P = 0.004) and presented with a relative apical sparing distribution (P < 0.001) matched by reduction of radial peak systolic strain of basal segments (P = 0.003). Apical rotation and twist were significantly higher immediately after the competition compared with follow-up (P < 0.05).

Conclusion

Strenuous exercise in master triathletes is associated with a reversible regional increase in myocardial edema and reduction of radial peak systolic strain, both presenting with a relative apical sparing pattern.

Lung Ultrasound-Guided Fluid Management versus Standard Care in Surgical ICU Patients: A Randomised Controlled Trial

The value of lung ultrasound (LU) in assessing extravascular lung water (EVLW) was demonstrated by comparing LU with gold-standard methods for EVLW assessment. However, few studies have analysed the value of B-Line score (BLS) in guiding fluid management during critical illness. The purpose of this trial was to evaluate if a BLS-guided fluid management strategy could improve fluid balance and short-term mortality in surgical intensive care unit (ICU) patients. We conducted a randomised, controlled trial within the ICUs of two university hospitals. Critically ill patients were randomised upon ICU admission in a 1:1 ratio to BLS-guided fluid management (active group) or standard care (control group). In the active group, BLS was monitored daily until ICU discharge or day 28 (whichever came first). On the basis of BLS, different targets for daily fluid balance were set with the aim of avoiding or correcting moderate/severe EVLW increase. The primary outcome was 28-day mortality. Over 24 months, 166 ICU patients were enrolled in the trial and included in the final analysis. Trial results showed that daily BLS monitoring did not lead to a different cumulative fluid balance in surgical ICU patients as compared to standard care. Consecutively, no difference in 28-day mortality between groups was found (10.5% vs. 15.6%, p = 0.34). However, at least 400 patients would have been necessary for conclusive results.

Incidence of Swimming-Induced Pulmonary Edema: A Cohort Study Based on 47,600 Open-Water Swimming Distances

Background

Despite increasing awareness of swimming-induced pulmonary edema (SIPE), large population-based studies are lacking and the incidence is unknown.

Research Question

What is the incidence of SIPE in a mixed group of competitive and recreational swimmers during a large open-water swimming event?

Methods

In four consecutive years (2016-2019), a prospective cohort study was conducted during Sweden’s largest open-water swimming event, Vansbrosimningen. All swimmers seeking medical care with acute respiratory symptoms were eligible for the study. SIPE diagnosis was based on clinical findings in 2016 and 2017 and pulmonary edema assessed by lung ultrasound in 2018 and 2019. Data on patient characteristics, clinical findings, and information about the race were collected.

Results

Based on 47,573 consecutive swimming distances, 322 patients with acute respiratory symptoms (0.68%; CI, 0.61%-0.75%) were treated at the mobile medical unit. Of these, 211 patients (0.44%; CI, 0.39%-0.51%) received a diagnosis of SIPE. The annual incidence of SIPE was 0.34%, 0.47%, 0.41%, and 0.57%, respectively, from 2016 through 2019. Most patients diagnosed with SIPE were women (90%), despite about equal percentages of men and women participating (47% men and 53% women). The incidence of SIPE overall was 0.75% in women and 0.09% in men. The incidence increased with age, from 0.08% in the youngest age group (18-30 years) to 1.1% in the oldest age group (≥ 61 years). Based on multiple logistic regression analysis, the adjusted odds for SIPE occurring was 8.59 times higher for women compared with men and 12.74 times higher for the oldest age group compared with the youngest age group.

Interpretation

The incidence of SIPE over 4 years during a large open-water swimming event in Sweden was 0.44%. The incidence was higher in women than in men and increased with age.

Late-Presenting Swimming-Induced Pulmonary Edema: A Case Report Series from the Norseman Xtreme Triathlon

Swimming-induced pulmonary edema (SIPE) may develop during strenuous physical exertion in water. This case series reports on three cases of suspected late-presenting SIPE during the Norseman Xtreme Triathlon. A 30-year-old male professional (PRO) triathlete, a 40-year-old female AGE GROUP triathlete and a 34-year-old male AGE GROUP triathlete presented with shortness of breath, chest tightness and coughing up pink sputum during the last part of the bike phase. All three athletes reported an improvement in breathing during the first major uphill of the bike phase and increasing symptoms during the downhill. The PRO athlete had a thoracic computed tomography, and the scan showed bilateral ground glass opacity in the peripheral lungs. The male AGE GROUP athlete had a normal chest x-ray. Both athletes were admitted for further observation and discharged from hospital the following day, with complete regression of symptoms. The female athlete recovered quickly following pre-hospital oxygen treatment. Non-cardiogenic pulmonary edema associated with endurance sports is rare but potentially very dangerous. Knowledge and awareness of possible risk factors and symptoms are essential, and the results presented in this report emphasize the importance of being aware of the possible delayed development of symptoms. To determine the presence of pulmonary edema elicited by strenuous exercise, equipment for measuring oxygen saturation should be available for the medical staff on site.

Lung Ultrasound Guided Fluid Management Protocol for the Critically Ill Patient: study protocol for a multi-centre randomized controlled trial

Background

In routine intensive care unit (ICU) practice, fluids are often administered without a safety limit, which may lead to fluid overload and decreased survival. Recently, B-lines score (BLS) has been validated as a lung ultrasound (LUS) quantification of pulmonary congestion. This suggests that LUS may provide a safety threshold to conduct fluid therapy and to avoid overhydration. However, there is no randomized study to test the utility of LUS in guiding fluid management in ICU patients by using a pre-specified BLS cut-off value as a threshold for fluid removal.

Methods

LUS Guided Fluid Management Protocol for the Critically Ill Patient is a prospective, multi-centre, randomized controlled trial. Five hundred ICU patients will be randomly assigned in a 1:1 ratio, to protocolized LUS-based fluid management or usual care. The trial intervention will start on ICU admission and will consist in daily assessment of BLS and triggered evacuation of excessive fluids with loop diuretics (Furosemide) when BLS ≥ 15. If rebalancing volume status with diuretics fails, forced evacuation by ultrafiltration will be used. The main endpoint is death from all causes at 28 days from randomization. The secondary outcomes are presence and time-course evolution of organ dysfunctions, ICU- and hospital length of stay, all-cause mortality at 90 days, and health economics data.

Discussion

If study results will show that LUS guided fluid management protocol improves outcome in ICU patients, it will be the base for other studies to refine this protocol or track those categories of critically ill patients to whom it may bring maximum benefits.

Trial registration

ClinicalTrials.gov, NCT03393065. Registered on 8 January 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3345-0) contains supplementary material, which is available to authorized users.

Transthoracic sonographic assessment of B-line scores during ascent to altitude among healthy trekkers

Sonographic B-lines can indicate pulmonary interstitial edema. We sought to determine the incidence of subclinical pulmonary edema measured by sonographic B-lines among lowland trekkers ascending to high altitude in the Nepal Himalaya. Twenty healthy trekkers underwent portable sonographic examinations and arterial blood draws during ascent to 5160 m over ten days. B-lines were identified in twelve participants and more frequent at 4240 m and 5160 m compared to lower altitudes (P < 0.03). There was a strong negative correlation between arterial oxygen saturation and the number of B-lines at 5160 m (ρ = -0.75, P = 0.008). Our study contributes to the growing body of literature demonstrating the development of asymptomatic pulmonary edema during ascent to high altitude. Portable lung sonography may have utility in fieldwork contexts such as trekking at altitude, but further research is needed in order to clarify its potential clinical applicability.

Acute Cardiovascular Adaptation to Strenuous Exercise: An Integrative Ultrasound Study

OBJECTIVES

The aim of this study was to evaluate the acute effects of participation in an Ironman distance triathlon competition on arterial function by ultrasound, in relation to cardiac function and body water content.

METHODS

Twenty-eight male triathletes participating in an Ironman distance competition underwent carotid, femoral, and cardiac ultrasound examinations. Moreover, the presence of extravascular lung water was identified by lung echo B-lines (echogenic coherent wedge-shaped signal with a narrow origin from the hyperechoic pleural line) at rest and within 20 minutes of arrival.

RESULTS

At the end of the competition, athletes showed an increased heart rate (mean ± SD, from 60.2 ± 13.1 to 82.8 ± 15.6 beats/min; P < .0001) and unchanged mean blood pressure (from 93 ± 14 to 91 ± 10 mm Hg; P > .05) in the presence of negligible dehydration (total body water from 48.0 ± 4.0 to 46.5 ± 3.9 kg; P > .05). Cardiac output increased (from 5.5 ± 1.2 to 6.7 ± 2.4 L/min; P < .05) in the presence of an unchanged stroke volume (from 64 ± 14 to 59 ± 16 mL; P > .05) and unchanged left ventricular elastance (from 1.52 ± 0.48 to 1.39 ± 0.48 mm Hg/mL/m² ; P > .05). The mean carotid diameter increased (from 7.19 ± 0.65 to 7.61 ± 0.76 mm; P < .05), whereas the mean femoral diameter was unchanged at the end of the competition (from 10.41 ± 0.83 to 10.49 ± 0.82 mm; P > .05). Carotid intima-media thickness was significantly reduced (from 537 ± 70 to 495 ± 70 μm; P < .05), whereas B-lines increased significantly after the competition (from 1 [0-4] to 12 [5-23]; P < .0001).

CONCLUSIONS

These data suggest different acute functional adaptation in central arteries with respect to peripheral leg vessels.

Swimming induced pulmonary oedema in athletes - a systematic review and best evidence synthesis

Background

Swimming induced pulmonary oedema is an uncommon occurrence and usually presents during strenuous distance swimming in cold water. The prevalence is most likely underreported and the underlying mechanisms are controversial. The purpose of this study was to summarize the evidence with regards to prevalence, pathophysiology and treatment of swimming induced pulmonary oedema in endurance athletes.

Methods

Medline, Embase, Scopus and Google Scholar were searched and level I-IV from 1970 to 2017 were included. For clinical studies, only publications reporting on swimming-induced pulmonary oedema were considered. Risk of bias was assessed with the ROBINS-I tool, and the quality of evidence was assessed with the Cochrane GRADE system. For data synthesis and analysis, a best evidence synthesis was used.

Results

A total of 29 studies were included (174 athletes). The most common symptom was cough, dyspnoea, froth and haemoptysis. The risk of bias for the clinical studies included 13 with moderate risk, 3 with serious, and 4 with critical. Four of the pathophysiology studies had a moderate risk, 3 a serious risk, and 1 a critical risk of bias. A best evidence analysis demonstrated a strong association between cold water immersion and in increases of CVP (central venous pressure), MPAP (mean pulmonary arterial pressure), PVR (peripheral vascular resistance) and PAWP (pulmonary arterial wedge pressure) resulting in interstitial asymptomatic oedema.

Conclusion

The results of this study suggest a moderate association between water temperature and the prevalence of SIPE. The presence of the clinical symptoms cough, dyspnoea, froth and haemoptysis are strongly suggestive of SIPE during or immediately following swimming. There is only limited evidence to suggest that there are pre-existing risk factors leading to SIPE with exposure to strenuous physical activity during swimming. There is strong evidence that sudden deaths of triathletes are often associated with cardiac abnormalities.

A New Modality for the Diagnosis of Bleomycin-induced Toxicity: Ultrasonography

OBJECTIVE

To evaluate the role of ultrasonography (USG) in the diagnosis of bleomycin-induced pulmonary toxicity (BT).

MATERIAL AND METHODS

The study included patients with suspected BT during treatment with bleomycin due to various oncologic diseases between June 2015 and May 2017. The patients initially underwent clinical and high-resolution computed tomography (HRCT) examinations and pulmonary function tests (PFT)-diffusing capacity of the lung for carbon monoxide (DLCO), followed by registration of USG findings-number of comet tail artifact (CTA) images by a different pulmonologist. We compared the findings from USG, HRCT, and PFT-DLCO tests between BT and non-BT groups. With the diagnosis based on clinical-radiologic and PFT-DLCO assessments taken as the gold standard, we determined the sensitivity and specificity of the USG outcomes for diagnosis of BT.

RESULTS

The study included a total of 30 patients. Nine patients were diagnosed as having BT according to their clinical and radiologic findings and PFT-DLCO measurements. The mean number of CTA images was 68.7±22 in patients with BT vs 28.2±9.3 in those without BT (P<.001). The difference in CTA images between the patients with and without ground glass density was statistically significant (28.3±9.5 and 64.6±24.5, respectively, P<.001). In patients with BT, there was a negative correlation between the number of CTAs and DLCO% and FVC% values (P=.004; P=.016). USG had a sensitivity of 100%, and a specificity of 95% diagnosing BT in selected patients.

CONCLUSION

In bleomycin-induced toxicity, USG findings are correlated with HRCT and PFT-DLCO findings, with a remarkably increased number of CTAs in BT. Thoracic USG examination is a diagnostic tool with a high sensitivity and specificity for diagnosing BT.

Chest Ultrasonography in Modern Day Extreme Settings: From Military Setting and Natural Disasters to Space Flights and Extreme Sports

Chest ultrasonography (CU) is a noninvasive imaging technique able to provide an immediate diagnosis of the underlying aetiology of acute respiratory failure and traumatic chest injuries. Given the great technologies, it is now possible to perform accurate CU in remote and adverse environments including the combat field, extreme sport settings, and environmental disasters, as well as during space missions. Today, the usage of CU in the extreme emergency setting is more likely to occur, as this technique proved to be a fast diagnostic tool to assist resuscitation manoeuvres and interventional procedures in many cases. A scientific literature review is presented here. This was based on a systematic search of published literature, on the following online databases: PubMed and Scopus. The following words were used: "chest sonography," " thoracic ultrasound," and "lung sonography," in different combinations with "extreme sport," "extreme environment," "wilderness," "catastrophe," and "extreme conditions." This manuscript reports the most relevant usages of CU in the extreme setting as well as technological improvements and current limitations. CU application in the extreme setting is further encouraged here.

Observational study of potential risk factors of immersion pulmonary edema in healthy divers: exercise intensity is the main contributor

BACKGROUND

The risk factors of pulmonary edema induced by diving in healthy subjects are not well known. The aim of the present study was to assess the parameters contributing to the increase in extravascular lung water after diving.

METHODS

This study was carried out in a professional diving institute. All divers participating in the teaching program from June 2012 to June 2014 were included in the study. Extravascular lung water was assessed using the detection of ultrasound lung comets (ULC) by chest ultrasonography. Clinical parameters and dive profiles were recorded using a questionnaire and a dive computer.

RESULTS

One-hundred six divers were investigated after 263 dives. They used an open-circuit umbilical supplying compressed gas diving apparatus in 202 cases and a self-contained underwater breathing apparatus in 61 cases. A generalized linear mixed model analysis was performed which demonstrated that the dive induced a significant increase in ULC score (incidence rate ratio: 3.16). It also identified that the predictive variable of increased extravascular lung water after the dive was the exercise intensity at depth (z = 3.99, p < 0.0001). The other parameters studied such as the water temperature, dive profile, hyperoxic exposure, or anthropometric data were not associated with the increase in extravascular lung water after the dive.

CONCLUSIONS

In this study, the exercise intensity was the main contributor to the increase in extravascular lung water in healthy divers. To improve the prevention of immersion pulmonary edema, the exercise intensity experienced during the dive should thus be adapted to the aerobic fitness level of the divers.

Usefulness of lung ultrasound B-lines in connective tissue disease-associated interstitial lung disease: a literature review

Interstitial lung disease (ILD) is a major pulmonary manifestation of connective tissue disease (CTD), leading to significant morbidity and mortality. Chest high-resolution computed tomography (HRCT) is presently considered the diagnostic gold standard for pulmonary fibrosis diagnosis and quantification in the clinical arena. However, not negligible doses of ionizing radiation limit the use of HRCT, especially for serial follow-up in younger female patients. In the past decade, lung ultrasound (LUS) has been proposed to assess ILD by detecting and quantifying sonographic B-lines. Previous studies demonstrate that B-lines have a good diagnostic accuracy, especially high sensitivity, and correlate well with HRCT findings, suggesting LUS as a novel, non-invasive, and non-ionizing imaging method to be used in patients with CTD-ILD. Although preliminary data are promising, challenges and controversies still remain. For example, the mechanisms of B-line generation are not fully understood; the diagnostic accuracy and performance characteristics of LUS partially depend on the scanning scheme and scoring system used; and up-to-date B-lines cannot discriminate the early cellular inflammation from the chronic fibrotic phase in CTD-ILD. Therefore it is important for clinicians to understand the strengths and limitations of LUS in CTD-ILD patients, to maximize its value.

Pulmonary Aspects of Exercise and Sports

Although the lungs are a critical component of exercise performance, their response to exercise and other environmental stresses is often overlooked when evaluating pulmonary performance during high workloads. Exercise can produce capillary leakage, particularly when left atrial pressure increases related to left ventricular (LV) systolic or diastolic failure. Diastolic LV dysfunction that results in elevated left atrial pressure during exercise is particularly likely to result in pulmonary edema and capillary hemorrhage. Data from race horses, endurance athletes, and triathletes support the concept that the lungs can react to exercise and immersion stress with pulmonary edema and pulmonary hemorrhage. Immersion in water by swimmers and divers can also increase stress on pulmonary capillaries and result in pulmonary edema. Swimming-induced pulmonary edema and immersion pulmonary edema in scuba divers are well-documented events caused by the fluid shifts that occur with immersion, elevated pulmonary venous pressure during extreme exercise, and negative alveolar pressure due to inhalation resistance. Prevention strategies include avoiding extreme exercise, avoiding over hydration, and assuring that inspiratory resistance is minimized.

Thoraco-abdominal coordination and performance during uphill running at altitude

INTRODUCTION

Running races on mountain trails at moderate-high altitude with large elevation changes throughout has become increasingly popular. During exercise at altitude, ventilatory demands increase due to the combined effects of exercise and hypoxia.

AIM

To investigate the relationships between thoraco-abdominal coordination, ventilatory pattern, oxygen saturation (SpO2), and endurance performance in runners during high-intensity uphill exercise.

METHODS

Fifteen participants (13 males, mean age 42±9 yrs) ran a "Vertical Kilometer," i.e., an uphill run involving a climb of approximately 1000 m with a slope greater than 30%. The athletes were equipped with a portable respiratory inductive plethysmography system, a finger pulse oximeter and a global positioning unit (GPS). The ventilatory pattern (ventilation (VE), tidal volume (VT), respiratory rate (RR), and VE/VT ratio), thoraco-abdominal coordination, which is represented by the phase angle (PhA), and SpO2 were evaluated at rest and during the run. Before and after the run, we assessed respiratory function, respiratory muscle strength and the occurrence of interstitial pulmonary edema by thoracic ultrasound.

RESULTS

Two subjects were excluded from the respiratory inductive plethysmography analysis due to motion artifacts. A quadratic relationship between the slope and the PhA was observed (r = 0.995, p = 0.036). When the slope increased above 30%, the PhA increased, indicating a reduction in thoraco-abdominal coordination. The reduced thoraco-abdominal coordination was significantly related to reduced breathing efficiency (i.e., an increased VE/VT ratio; r = 0.961, p = 0.038) and SpO2 (r = -0.697, p<0.001). Lower SpO2 values were associated with lower speeds at 20%≥slope≤40% (r = 0.335, p<0.001 for horizontal and r = 0.36, p<0.001 for vertical). The reduced thoraco-abdominal coordination and consequent reduction in SpO2 were associated with interstitial pulmonary edema.

CONCLUSION

Reductions in thoraco-abdominal coordination are associated with a less efficient ventilatory pattern and lower SpO2 during uphill running. This fact could have a negative effect on performance.

Stress echo 2020: the international stress echo study in ischemic and non-ischemic heart disease

BACKGROUND

Stress echocardiography (SE) has an established role in evidence-based guidelines, but recently its breadth and variety of applications have extended well beyond coronary artery disease (CAD). We lack a prospective research study of SE applications, in and beyond CAD, also considering a variety of signs in addition to regional wall motion abnormalities.

METHODS

In a prospective, multicenter, international, observational study design, > 100 certified high-volume SE labs (initially from Italy, Brazil, Hungary, and Serbia) will be networked with an organized system of clinical, laboratory and imaging data collection at the time of physical or pharmacological SE, with structured follow-up information. The study is endorsed by the Italian Society of Cardiovascular Echography and organized in 10 subprojects focusing on: contractile reserve for prediction of cardiac resynchronization or medical therapy response; stress B-lines in heart failure; hypertrophic cardiomyopathy; heart failure with preserved ejection fraction; mitral regurgitation after either transcatheter or surgical aortic valve replacement; outdoor SE in extreme physiology; right ventricular contractile reserve in repaired Tetralogy of Fallot; suspected or initial pulmonary arterial hypertension; coronary flow velocity, left ventricular elastance reserve and B-lines in known or suspected CAD; identification of subclinical familial disease in genotype-positive, phenotype- negative healthy relatives of inherited disease (such as hypertrophic cardiomyopathy).

RESULTS

We expect to recruit about 10,000 patients over a 5-year period (2016-2020), with sample sizes ranging from 5,000 for coronary flow velocity/ left ventricular elastance/ B-lines in CAD to around 250 for hypertrophic cardiomyopathy or repaired Tetralogy of Fallot. This data-base will allow to investigate technical questions such as feasibility and reproducibility of various SE parameters and to assess their prognostic value in different clinical scenarios.

CONCLUSIONS

The study will create the cultural, informatic and scientific infrastructure connecting high-volume, accredited SE labs, sharing common criteria of indication, execution, reporting and image storage of SE to obtain original safety, feasibility, and outcome data in evidence-poor diagnostic fields, also outside the established core application of SE in CAD based on regional wall motion abnormalities. The study will standardize procedures, validate emerging signs, and integrate the new information with established knowledge, helping to build a next-generation SE lab without inner walls.

Usefulness of Lung Ultrasound in Neonatal Congenital Heart Disease (LUSNEHDI): Lung Ultrasound to Assess Pulmonary Overflow in Neonatal Congenital Heart Disease

This study aimed to explore the pattern of lung ultrasound (LUS) in newborns with congenital heart disease (CHD) and to investigate the accuracy of LUS assessing pulmonary overflow (PO) during the first days of life. Lung ultrasound was performed in 51 newborns during the first days of life, and newborns were classified in two groups depending on the predisposition to develop POas evaluated by the abundance of B-lines. The results were compared to the physical examination (PE), chest X-ray, and echocardiography. In both groups there were no differences in abundance of B-lines during the first days of life, but those with a type of CHD with a trend to develop PO had a higher B-lines score after 72 h (p < 0.05) with a good correlation with echocardiography findings and with a better sensibility than PE and chest X-ray. We found that LUS is a reliable tool for the diagnosis of PO and may be useful to monitor and optimize therapy, which should be further validated in multicentre studies.

Beyond the Bruce Protocol: Advanced Exercise Testing for the Sports Cardiologist

Exercise testing is an important tool for determining baseline fitness as well as to diagnose limitations in performance. The Bruce protocol has become the standard for exercise testing protocol in many exercise physiology laboratories, but is rarely a suitable test for athletes who often have complex hemodynamic and metabolic demands during exercise required for practice and competition. We describe the approach for exercise testing beyond the Bruce protocol and focus on strategies to individualize the testing protocol to the metabolic demands of an athlete's sport.

Hypothesised mechanisms of swimming-related death: a systematic review

BACKGROUND

Recent reports from triathlon and competitive open-water swimming indicate that these events have higher rates of death compared with other forms of endurance sport. The potential causal mechanism for swimming-related death is unclear.

OBJECTIVE

To examine available studies on the hypothesised mechanisms of swimming-related death to determine the most likely aetiologies.

MATERIAL AND METHODS

MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews (1950 to present) were searched, yielding 1950 potential results, which after title and citation reviews were reduced to 83 possible reports. Studies included discussed mechanisms of death during swimming in humans, and were Level 4 evidence or higher.

RESULTS

A total of 17 studies (366 total swimmers) were included for further analysis: 5 investigating hyperthermia/hypothermia, 7 examining cardiac mechanisms and responses, and 5 determining the presence of pulmonary edema. The studies provide inconsistent and limited-quality or disease-oriented evidence that make definitive conclusions difficult.

CONCLUSIONS

The available evidence is limited but may suggest that cardiac arrhythmias are the most likely aetiology of swimming-related death. While symptoms of pulmonary edema may occur during swimming, current evidence does not support swimming-induced pulmonary edema as a frequent cause of swimming-related death, nor is there evidence to link hypothermia or hyperthermia as a causal mechanism. Further higher level studies are needed.

B-Lines in Assessment of Pulmonary Hypertension in Patients With Interstitial Lung Diseases: Feasibility of Transthoracic Lung Sonographic Signs

OBJECTIVES

This study was conducted to evaluate the value of sonographic B-lines (previously called "comet tail artifacts") in assessment of pulmonary hypertension in patients with interstitial lung diseases.

METHODS

One hundred thirty-four patients with clinically diagnosed interstitial lung diseases complicated by pulmonary hypertension underwent transthoracic lung sonography and Doppler echocardiography for assessment of the presence of B-lines, the distance between them, and the pulmonary artery (PA) systolic pressure. A correlation analysis and a receiver operating characteristic curve analysis were performed.

RESULTS

All patients had diffuse bilateral B-lines. The maximum number of B-lines seen in any positive zone (not a summation) was significantly correlated with the severity of PA systolic pressure (r= 0.812; P< .0001), and a linear regression equation could be demonstrated: that is, y = 6.06 x + 17.57, where x and y represent the number of B-lines and PA systolic pressure, respectively. A cutoff of more than 4 B-lines seen in any positive zone had 89.5% sensitivity, 85.0% specificity, and 87.2% accuracy in predicting elevated PA pressure (>30 mm Hg).

CONCLUSIONS

The number of B-lines is useful in assessment of pulmonary hypertension, especially when tricuspid regurgitation and pulmonary valve regurgitation do not exist or cannot be satisfactorily measured by Doppler echocardiography.

Innovative approach to interpret the variability of biomarkers after ultra-endurance exercise: the multifactorial analysis

AIMS

We assessed the inter-relationship that exists between variations of different biochemical and hematological parameters following strenuous endurance exercise in Ironmen by using multiple factor analysis (MFA). MFA was used to estimate the associations among groups of parameters in order to identify concurrent changes in many different biochemical variables.

MATERIALS & METHODS

In total, 14 Ironman athletes were followed before and early after a race. MFA was applied to the parameters that showed a significant variation after the race, as we previously described in detail. Specifically, MFA standardizes data in each group and calculates the global axes (GAs), which are the linear combination of original parameters that maximize the global data variance.

RESULTS

MFA identified three global axes (GAs) as significant, explaining approximately 62% of the global data variance. The first GA contained NT-proBNP, IL-1ra, IL-6, IL-8 and the oxidative index. The second and third GAs included calcium, creatinine, potassium, uric acid, hemoglobin, hematocrit and glucose. Analysis of the first two GAs showed that changes in the oxidative index were associated with variations in IL-8 and NT-proBNP.

CONCLUSION

Among all the variables considered, MFA evidenced a close relationship between variations in oxidative stress, IL-8 and NT-proBNP, which may have a meaning in the mechanisms related to the physiological response after strenuous acute exercise.

Lung ultrasound for the evaluation of pulmonary congestion in outpatients: a comparison with clinical assessment, natriuretic peptides, and echocardiography

OBJECTIVES

The aim of this study was to define the performance of lung ultrasound (LUS) compared with clinical assessment, natriuretic peptides, and echocardiography, to evaluate decompensation in patients with systolic heart failure (HF) in an outpatient clinic.

BACKGROUND

Evaluation of pulmonary congestion in chronic HF is challenging. LUS has been recently proposed as a reliable tool for the semiquantification of extravascular lung water through assessment of B-lines.

METHODS

This was a cohort study of patients with moderate to severe systolic HF. Receiver-operating characteristic (ROC) analyses were performed to compare LUS with a previously validated clinical congestion score (CCS), amino-terminal portion of B-type natriuretic peptide (NT-proBNP), E/e' ratio, chest x-ray, and 6-min walk test.

RESULTS

Ninety-seven patients were enrolled. Decompensation was present in 57.7% of patients when estimated by CCS, 68% by LUS, 53.6% by NT-proBNP, and 65.3% by E/e' ≥15. The number of B-lines was correlated to NT-proBNP (r = 0.72; p < 0.0001), E/e' (r = 0.68; p < 0.0001), and CCS (r = 0.43; p < 0.0001). In ROC analyses, considering as reference for decompensation a combined method (E/e' ≥ 15 and/or NT-proBNP >1,000 pg/ml), LUS yielded a C-statistic of 0.89 (95% confidence interval: 0.82 to 0.96), providing the best accuracy with a cutoff ≥ 15 B-lines (sensitivity 85%, specificity 83%). A systematic approach using CCS, E/e', NT-proBNP, chest x-ray, and 6-min walk test in different combinations as reference for decompensation also corroborated this cutoff and found a similar accuracy for LUS.

CONCLUSIONS

In an HF outpatient clinic, B-lines were significantly correlated with more established parameters of decompensation. A B-line ≥15 cutoff could be considered for a quick and reliable assessment of decompensation in outpatients with HF.

Clinical review: the role of ultrasound in estimating extra-vascular lung water

The estimation of extra-vascular lung water (EVLW) is an essential component in the assessment of critically ill patients. EVLW is independently associated with mortality and its manipulation has been shown to improve outcome. Accurate assessment of lung water is possible with CT and MR imaging but these are impractical for real-time measurement in sick patients and have been superseded by single thermal dilution techniques. While useful, single thermo-dilution requires repeated calibration and is prone to error, suggesting a need for other monitoring methods. Traditionally the lung was not thought amenable to ultrasound examination owing to the high acoustic impedance of air; however, the identification of artefacts in diseased lung has led to increased use of ultrasound as a point of care investigation for both diagnosis and to monitor response to interventions. Following the initial description of B-lines in association with increased lung water, accumulating evidence has shown that they are a useful and responsive measure of the presence and dynamic changes in EVLW. Animal models have confirmed a correlation with lung gravimetry and the utility of B-lines has been demonstrated in many clinical situations and correlated against other established measures of EVLW. With increasing availability and expertise the role of ultrasound in estimating EVLW should be embedded in clinical practice and incorporated into clinical algorithms to aid decision making. This review looks at the evidence for ultrasound as a valid, easy to use, non-invasive point of care investigation to assess EVLW.

Ultrasound in sports medicine: relevance of emerging techniques to clinical care of athletes

The applications of ultrasound in managing the clinical care of athletes have been expanding over the past decade. This review provides an analysis of the research that has been published regarding the use of ultrasound in athletes and focuses on how these emerging techniques can impact the clinical management of athletes by sports medicine physicians. Electronic database literature searches were performed using the subject terms 'ultrasound' and 'athletes' from the years 2003 to 2012. The following databases were searched: PubMed, Web of Science, Cochrane Library, CINAHL, and SPORTDiscus™. The search produced 617 articles in total, with a predominance of articles focused on cardiac and musculoskeletal ultrasound. 266 of the studies involved application of ultrasound in evaluating the cardiovascular properties of athletes, and 151 studies involved musculoskeletal ultrasound. Other applications of ultrasound included abdominal, vascular, bone density and volume status. New techniques in echocardiography have made significant contributions to the understanding of the physiological changes that occur in the athlete's heart in response to the haemodynamic stress associated with different types of activity. The likely application of these techniques will be in managing athletes with hypertrophic cardiomyopathy, and the techniques are near ready for application into clinical practice. These techniques are highly specialized, however, and will require referral to dedicated laboratories to influence the clinical management of athletes. Investigation of aortic root pathology and pulmonary vascular haemodynamics are also emerging, but will require additional studies with larger numbers and outcomes analysis to validate their clinical utility. Some of these techniques are relatively simple, and thus hold the potential to enter clinical management in a point-of-care fashion. Musculoskeletal ultrasound has demonstrated a number of diagnostic and therapeutic techniques applicable to pathology of the shoulder, elbow, wrist, hand, hip, knee and ankle. These techniques have been applied mainly to the management of impingement syndromes, tendinopathies and arthritis. Many of these techniques have been validated and have entered clinical practice, while more recently developed techniques (such as dynamic ultrasound and platelet-rich plasma injections) will require further research to verify efficacy. Research in musculoskeletal ultrasound has also been helpful in identifying risk factors for injury and, thus, serving as a focus for developing interventions. Research in abdominal ultrasound has investigated the potential role of ultrasound imaging in assessing splenomegaly in athletes with mononucleosis, in an attempt to inform decisions and policies regarding return to play. Future research will have to demonstrate a reduction in adverse events in order to justify the application of such a technique into policy. The role of ultrasound in assessing groin pain and abdominal pain in ultraendurance athletes has also been investigated, providing promising areas of focus for the development of treatment interventions and physical therapy. Finally, preliminary research has also identified the role of ultrasound in addressing vascular disease, bone density and volume status in athletes. The potential applications of ultrasound in athletes are broad, and continuing research, including larger outcome studies, will be required to establish the clinical utility of these techniques in the care of athletes.

Portable bedside ultrasound: the visual stethoscope of the 21st century

Over the past decade technological advances in the realm of ultrasound have allowed what was once a cumbersome and large machine to become essentially hand-held. This coupled with a greater understanding of lung sonography has revolutionized our bedside assessment of patients. Using ultrasound not as a diagnostic test, but instead as a component of the physical exam, may allow it to become the stethoscope of the 21st century.