Pathophysiology of exercise intolerance in breast cancer survivors with preserved left ventricular ejection fraction.

Breast cancer (BC) survival rates have improved during the past two decades and as a result older BC survivors are at increased risk of developing heart failure (HF). Although the HF phenotype common to BC survivors has received little attention, BC survivors have a number of risk factors associated with HF and preserved ejection fraction (HFPEF) including older age, hypertension, obesity, metabolic syndrome and sedentary lifestyle. Moreover, not unlike HFPEF, BC survivors with preserved left ventricular ejection fraction (BCPEF) have reduced exercise tolerance measured objectively as decreased peak oxygen uptake (peak VO).

A Modern Definition of the Athlete's Heart-for Research and the Clinic.

Exercise training can have a profound effect on cardiac structure. Recent evidence suggests that the greatest determinants of exercise-induced cardiac remodeling are the intensity, duration, and frequency of training. This also has overlap with athlete fitness.

Acute effect of static exercise in patients with aortic regurgitation assessed by cardiovascular magnetic resonance: role of left ventricular remodelling.

Objective: In patients with aortic regurgitation (AR), the effect of static exercise (SE) on global ventricular function and AR severity has not been previously studied.

Methods: Resting and SE cardiovascular magnetic resonance (CMR) were prospectively performed in 23 asymptomatic patients with AR.

Results: During SE, we observed a decrease in regurgitant volume in both end-diastolic (EDV) and end-systolic (ESV) volume in both ventricles, as well as a slight decrease in LV ejection fraction (EF).

Right ventricular and pulmonary vascular reserve in asymptomatic BMPR2 mutation carriers.

Background: Non-invasive estimates have suggested that asymptomatic BMPR2 mutation carriers may have an abnormal pulmonary vascular response to exercise and hypoxia. However, this has not been assessed with "gold standard" invasive measures.

Methods: Eight controls and 8 asymptomatic BMPR2 mutation carriers underwent cardiac magnetic resonance imaging with simultaneous invasive pressure recording during bicycle exercise in normoxia, hypoxia and after sildenafil administration.

Insulin pump basal adjustment for exercise in type 1 diabetes: a randomised crossover study.

Aims/hypothesis: The aim of this study was to investigate the effects of exercise, vs rest, on circulating insulin and glucose, following pre-exercise insulin pump basal rate reduction.

Methods: This was an open-label, two-stage randomised crossover study of 14 adults (seven women, seven men) with type 1 diabetes established on insulin pump therapy. In each stage, participants fasted and insulin delivery was halved following a single insulin basal rate overnight.

Improving the physiological realism of experimental models.

The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models.

The Potential Cardiotoxic Effects of Exercise.

The emerging controversy related to the potential cardiotoxic effects of high doses of intense exercise need to be considered among the much stronger evidence that supports the pleomorphic benefits of exercise as a whole. However, there is fairly compelling evidence to support the association between long-term sport practice and an increased prevalence of atrial fibrillation and the fact that this relates to a chronic altered atrial substrate. This article was designed to challenge the reader with speculative science that suggests that exercise might promote permanent structural changes in the myocardium which can, in some individuals, predispose to arrhythmias.

Subepicardial delayed gadolinium enhancement in asymptomatic athletes: let sleeping dogs lie?

Background: Subepicardial delayed gadolinium enhancement (DGE) patches without underlying cardiomyopathy is poorly understood. It is often reported as the result of prior silent myocarditis. Its prognostic relevance in asymptomatic athletes is unknown; therefore, medical clearance for competitive sports participation is debated.

Relationship between Inflammatory Cytokines and Indices of Cardiac Dysfunction following Intense Endurance Exercise.

Objectives: Pro-inflammatory cytokines have been noted to increase following exercise but their relationship to exercise-induced cardiac dysfunction has not previously been investigated. We sought to evaluate whether exercise-induced cardiac dysfunction was associated with increases in cytokines, particularly the pro-inflammatory cytokines IL-1β, IL-12p70 and TNFα, which have been most implicated in cardiac pathology.

Methods: 40 well-trained endurance athletes underwent evaluation prior to and immediately following one of four endurance sporting events ranging from 3 to 11 hours duration.

Abnormal right ventricular relaxation in pulmonary hypertension.

Left ventricular diastolic dysfunction is a well-described complication of systemic hypertension. However, less is known regarding the effect of chronic pressure overload on right ventricular (RV) diastolic function. We hypothesized that pulmonary hypertension (PHT) is associated with abnormal RV early relaxation and that this would be best shown by invasive pressure measurement.