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In this correspondence, we highlight the risk of sudden cardiac death associated with undiagnosed cardiomyopathies. Life-threatening arrhythmias, which underlie sudden cardiac death, can be triggered by high intensity exercise. It raises the question whether, and if so, how athletes should be screened for cardiomyopathies. The example of practice from Italy is discussed. We also briefly discuss novel developments, such as wearable biosensors and machine learning, which could be applied to screening for cardiomyopathies in future.

El pulmón recibe sangre desde la circulación bronquial y pulmonar. La circulación pulmonar presenta importantes diferencias con la sistémica, sus vasos sanguíneos poseen características únicas que le permiten cumplir sus diferentes funciones, siendo la más importante el intercambio gaseoso. Existen múltiples factores, activos y pasivos, que están involucrados en la regulación de la resistencia vascular y flujo sanguíneo pulmonar.

There is a growing emphasis being placed on the potential for cuffless blood pressure (BP) estimation through modelling of morphological features from the photoplethysmogram (PPG) and electrocardiogram (ECG). However, the appropriate features and models to use remain unclear. We investigated the best features available from the PPG and ECG for BP estimation using both linear and non-linear machine learning models. We conducted a clinical study in which changes in BP ($$\Delta$$ Δ BP) were induced by an infusion of phenylephrine in 30 healthy volunteers (53.8% female, 28.0 (9.0) years old). We extracted a large and diverse set of features from both the PPG and the ECG and assessed their individual importance for estimating $$\Delta$$ Δ BP through Shapley additive explanation values and a ranking coefficient. We trained, tuned, and evaluated linear (ordinary least squares, OLS) and non-linear (random forest, RF) machine learning models to estimate $$\Delta$$ Δ BP in a nested leave-one-subject-out cross-validation framework. We reported the results as correlation coefficient ($$\rho _p$$ ρ p ), root mean squared error (RMSE), and mean absolute error (MAE). The non-linear RF model significantly ($$p p < 0.05 ) outperformed the linear OLS model using both the PPG and the ECG signals across all performance metrics. Estimating $$\Delta$$ Δ SBP using the PPG alone ($$\rho _p$$ ρ p = 0.86 (0.23), RMSE = 5.66 (4.76) mmHg, MAE = 4.86 (4.29) mmHg) performed significantly better than using the ECG alone ($$\rho _p$$ ρ p = 0.69 (0.45), RMSE = 6.79 (4.76) mmHg, MAE = 5.28 (4.57) mmHg), all $$p < 0.001$$ p < 0.001 . The highest ranking features from the PPG largely modelled increasing reflected wave interference driven by changes in arterial stiffness. This finding was supported by changes observed in the PPG waveform in response to the phenylephrine infusion. However, a large number of features were required for accurate BP estimation, highlighting the high complexity of the problem. We conclude that the PPG alone may be further explored as a potential single source, cuffless, blood pressure estimator. The use of the ECG alone is not justified. Non-linear models may perform better as they are able to incorporate interactions between feature values and demographics. However, demographics may not adequately account for the unique and individualised relationship between the extracted features and BP.

Circadian rhythms in blood pressure (BP) may in some cases be indicative of an increased risk of adverse cardiovascular events. However, current methods for assessing these rhythms can be disruptive to sleep, work, and daily activities. Features of the photoplethysmogram (PPG), which can be non-invasively and unobtrusively recorded, have been suggested as surrogate measures of BP. This work investigates the presence of a circadian rhythm in these features and evaluates their potential to classify nocturnal BP patterns. 742 patients who were discharged home from the ICU were selected from the MIMIC-III database. Our results show that a number of PPG features exhibit a clear and observable circadian rhythm. Of the 19 features evaluated, the circadian rhythms of 5 features outperformed heart rate (HR) in terms of correlation with the circadian rhythm of SBP ( ). We also present evidence that a metric combining the PPG features significantly improves BP phenotype classification accuracy. Clinical Relevance-This work suggests that a combined metric of PPG features may be able to accurately assess an individual's circadian rhythm of BP.

Circadian rhythms of blood pressure (BP) have key diagnostic significance in the assessment of hypertension. The night-time dip or rise in BP (10-20% decrease or increase compared to daytime BP), for example, has been shown to be a strong indicator for cardiovascular disease. However, current methods for assessing the circadian rhythms of BP can be disruptive to sleep, work, and daily activities. Pulse arrival time (PAT) has been suggested as a surrogate measure of BP. This work investigates the presence of a circadian rhythm in PAT and evaluates its application to classify nocturnal BP dip or rise. 769 patients who were discharged home from the ICU were selected from the MIMIC database. Our results show a clear and observable circadian rhythm of PAT that is strongly inversely correlated with BP (r = -0.89). The ratios between nocturnal and diurnal changes in PAT accurately classifies an individual as a nocturnal BP dipper (AUC = 0.72) or a riser (AUC = 0.71). Clinical Relevance - This work shows that you can accurately assess an individuals's circadian rhythm of BP using PAT.

Every year thousands of horses from Mexico and the United States of America (USA) are transported to slaughter in Mexico, but little is known about their welfare or pre-slaughter logistics. In this study, we recorded the origin, sex, age and condition of horses (121 journeys, 2648 animals) upon arrival to an abattoir in northern Mexico, including transport details. Horse welfare was measured indirectly via individual scores for body condition, coat quality, lameness, ocular and nasal discharge, as well as reactivity to a chute restraint test, all performed shortly after unloading. The average journey duration was 9.69 (±7.6) hours for horses from Mexico and 16.77 (±4.51) hours for horses from the USA (77 % of all journeys). The prevalence of ocular discharge, nasal discharge, skin wounds, lameness and diarrhoea, were 23 %, 12 %, 11 %, 9 %, 1 % (respectively) of all the horses observed, with no significant differences between Mexican and American horses (P = 0.05). During the chute test the American horses were calmer than the Mexican ones (P < 0.001), who were more restless and aggressive (P = 0.001). Likewise, vocalizations in their three variants during the restraint, neigh/whinny (P = 0.018), nicker (P < 0.001), and snort (P = 0.018), were more common in horses from Mexico. In order to help characterize fitness for transport, a two-step cluster analysis was applied using the welfare indicators, suggesting the existence of four clusters (C) evaluated on arrival at the abattoir (from good to very poor fitness): good (profile C4, n = 769, 29.1 %), average (profile C1, n = 799 horses, 30.2 %), poor (profile C3, n = 586, 22.1 %) and very poor (profile C2, n = 494, 18.6 %). In fact, the C4 best welfare group had 0% lame, 0% nasal discharge, 16.4 % ocular discharge, 7.9 % skin wounds. Instead, the C2 poorest welfare group had 45.8 % lame, 61.1 % nasal discharge, 42.8 % ocular discharge, and 19.9 % skin wounds. Results show potential for using nasal discharge, lameness and ocular discharge as key indicators of horse fitness and welfare on abattoir. The study provides detailed scientific data to help establish strategies regarding optimal days of recovery post-transport and fattening for homogenization of weights between animals of different origins, logistic planning, and optimization of logistic resources to minimize the biological cost of long-distance transport.

There is an increasing need for fast and accurate transfer of readings from blood glucose metres and blood pressure monitors to a smartphone mHealth application, without a dependency on Bluetooth technology. Most of the medical devices recommended for home monitoring use a seven-segment display to show the recorded measurement to the patient. We aimed to achieve accurate detection and reading of the seven-segment digits displayed on these medical devices using an image taken in a realistic scenario by a smartphone camera. A synthetic dataset of seven-segment digits was developed in order to train and test a digit classifier. A dataset containing realistic images of blood glucose metres and blood pressure monitors using a variety of smartphone cameras was also created. The digit classifier was evaluated on a dataset of seven-segment digits manually extracted from the medical device images. These datasets along with the code for its development have been made public. The developed algorithm first preprocessed the input image using retinex with two bilateral filters and adaptive histogram equalisation. Subsequently, the digit segments were automatically located within the image by two techniques operating in parallel: Maximally Stable Extremal Regions (MSER) and connected components of a binarised image. A filtering and clustering algorithm was then designed to combine digit segments to form seven-segment digits. The resulting digits were classified using a Histogram of Orientated Gradients (HOG) feature set and a neural network trained on the synthetic digits. The model achieved 93% accuracy on digits found on the medical devices. The digit location algorithm achieved a F1 score of 0.87 and 0.80 on images of blood glucose metres and blood pressure monitors respectively. Very few assumptions were made of the locations of the digits on the devices so that the proposed algorithm can be easily implemented on new devices.

Skin temperature has long been used as a natural indicator of vascular diseases in the extremities. Considerable correlation between oscillations in skin surface temperature and oscillations of skin blood flow has previously been demonstrated. We hypothesised that the impairment of blood flow in stenotic (subcutaneous) peripheral arteries would influence cutaneous temperature such that, by measuring gradients in the temperature distribution over skin surfaces, one may be able to diagnose or quantify the progression of vascular conditions in whose pathogenesis a reduction in subcutaneous blood perfusion plays a critical role (e.g. peripheral artery disease). As proof of principle, this study investigates the local changes in the skin temperature of healthy humans (15 male, 30.0 ± 5.2 years old, BMI 25.1 ± 2.2 kg/m 2 ) undergoing two physical challenges designed to vary their haemodynamic status. Skin temperature was measured in four central regions (forehead, neck, chest, and left shoulder) and four peripheral regions (left upper arm, forearm, wrist, and hand) using an infrared thermal camera. We compare inter-region patterns. Median temperature over the peripheral regions decreased from baseline after both challenges (maximum decrease: -2.09 ± 0.41 °C at 60 s after exercise; p = 0.0001 and -0.58 ± 0.14 °C at 180 s of cold-water immersion; p = 0.0013). Median temperature over the central regions showed no significant changes. Our results show that the non-contact measurement of perfusion-related changes in peripheral temperature from infrared video data is feasible. Further research will be directed towards the thermographic study of patients with symptomatic peripheral vascular disease.

RESUMEN: La Linea aspera localizada en el margen posterior de la diáfisis del fémur, es considerada una referencia topográfica, imagenológica y antropológica. Hacia la epífisis proximal, esta línea se divide en varias líneas divergentes. De ellas, la rama lateral da inserción al músculo glúteo máximo (Tuberositas glutea), mientras que la rama media da inserción al músculo pectíneo (Linea pectinea). Ambas estructuras se encuentran en Terminologia Anatomica (TA), sin embargo, la rama medial conocida como línea espiral, donde se origina el musculo vasto medial (VM), no se encuentra en TA. Se realizó una revisión de la literatura del área morfológica con el objetivo de recopilar, analizar y verificar el uso del término línea espiral en nóminas, terminologías, textos de anatomía y publicaciones científicas. Se revisaron la Nomina Anatomica de Basilea, Paris Nomina Anatomica y Terminologia anatomica FCAT (2001) y FIPAT (2011). También fueron seleccionados 45 libros y 20 artículos en idiomas inglés y español, con el fin de analizar textos, tablas e imágenes del fémur y/o VM. Se confeccionaron tablas para resumir la información obtenida. Su término no es mencionado en nóminas ni terminologías, sin embargo en la columna de inglés de TA, se utiliza como sinónimo de Linea pectinea. En algunos textos anatómicos y artículos científicos se observa que el término línea espiral se utiliza en relación a la descripción del fémur y/o al origen del VM. El uso del término en textos de anatomía y publicaciones científicas, con fines descriptivos, antropológicos y clínicos, sumado al hecho que dentro de los principios de TA el latín es el idioma oficial y se debe considerar un único nombre por término, con el fin de evitar confusiones, fundamentan la necesidad de incorporar a TA, el término línea espiral (Linea spiralis). SUMMARY: The Linea aspera located on the posterior margin of the femur diaphysis is considered a tomographic, imaging and anthropological reference. To the proximal epiphysis, this line is divided in several divergent lines. Of these, the lateral branch gives insertion to the gluteus maximus muscle (Tuberositas glutea), while the middle branch gives insertion to the pectineal muscle (pectinea line). Both structures are found in Terminologia Anatomica (TA), however the medial branch known as the Spiral Line, where the vastus medial muscle (VM) originates, is not found in TA. We aimed to collect, analyze and verify the level of use of the term Spiral line in terminologies, anatomy texts and scientific publications. Nomina Anatomica from Basilea (BNA), Paris Nomina Anatomica (PNA) y Terminologia anatomica FCAT (2001) and FIPAT (2011) were reviewed. In addition, 45 books and 20 articles in English and Spanish were also selected, in order to analyze text, tables and images of the femur and/or VM. Tables were made to summarize the information obtained. The term is not mentioned in payrolls or terminologies, however in the English column of TA, this term is used as a synonym for Linea pectinea. In some anatomical texts and scientific articles it is observed that the term spiral line is used in relation to the description of the femur and / or the origin of the vast medial. The use of the term in anatomy texts and scientific publications, for descriptive, anthropological and clinical purposes, added to the fact that within the principles of Anatomical Terminology Latin is the official language and should be considered a single name per term, in order to avoid confusion, they base the need to incorporate the term spiral line (Linea spiralis) into TA.

RESUMEN: La Linea aspera localizada en el margen posterior de la diáfisis del fémur, es considerada una referencia topográfica, imagenológica y antropológica. Hacia la epífisis proximal, esta línea se divide en varias líneas divergentes. De ellas, la rama lateral da inserción al músculo glúteo máximo (Tuberositas glutea), mientras que la rama media da inserción al músculo pectíneo (Linea pectinea). Ambas estructuras se encuentran en Terminologia Anatomica (TA), sin embargo, la rama medial conocida como línea espiral, donde se origina el musculo vasto medial (VM), no se encuentra en TA. Se realizó una revisión de la literatura del área morfológica con el objetivo de recopilar, analizar y verificar el uso del término línea espiral en nóminas, terminologías, textos de anatomía y publicaciones científicas. Se revisaron la Nomina Anatomica de Basilea, Paris Nomina Anatomica y Terminologia anatomica FCAT (2001) y FIPAT (2011). También fueron seleccionados 45 libros y 20 artículos en idiomas inglés y español, con el fin de analizar textos, tablas e imágenes del fémur y/o VM. Se confeccionaron tablas para resumir la información obtenida. Su término no es mencionado en nóminas ni terminologías, sin embargo en la columna de inglés de TA, se utiliza como sinónimo de Linea pectinea. En algunos textos anatómicos y artículos científicos se observa que el término línea espiral se utiliza en relación a la descripción del fémur y/o al origen del VM. El uso del término en textos de anatomía y publicaciones científicas, con fines descriptivos, antropológicos y clínicos, sumado al hecho que dentro de los principios de TA el latín es el idioma oficial y se debe considerar un único nombre por término, con el fin de evitar confusiones, fundamentan la necesidad de incorporar a TA, el término línea espiral (Linea spiralis).