Non-hyperaemic pressure ratios to guide percutaneous coronary intervention.

The use of fractional flow reserve (FFR) in guiding revascularisation improves patient outcomes and has been well-established in clinical guidelines. Despite this, the uptake of FFR has been limited, likely attributable to the perceived increase in procedural time and use of hyperaemic agents that can cause patient discomfort. This has led to the development of instantaneous wave-free ratio (iFR), an alternative non-hyperaemic pressure ratio (NHPR). Since its inception, the use of iFR has been supported by an increasing body of evidence and is now guideline recommended. More recently, other commercially available NHPRs including diastolic hyperaemia-free ratio and resting full-cycle ratio have emerged. Studies have demonstrated that these indices, in addition to mean distal coronary artery pressure to mean aortic pressure ratio, are mathematically analogous (with specific nuances) to iFR. Additionally, there is increasing data demonstrating the equivalent diagnostic performance of alternative NHPRs in comparison with iFR and FFR. These NHPRs are now integral within most current pressure wire systems and are commonly available in the catheter laboratory. It is therefore key to understand the fundamental differences and evidence for NHPRs to guide appropriate clinical decision-making.

Physical activity in survivors of childhood acute lymphoblastic leukaemia.

AIM: To objectively measure levels of physical activity in children, following treatment for acute lymphoblastic leukaemia (ALL). METHODS: Nineteen children who had completed treatment for ALL 6 months-5 years prior to study enrollment wore an accelerometer for 2 weekdays and 2 weekend days. RESULTS: The children spent an average of 141 +/- 74 min/day engaged in moderate to vigorous physical activity (MVPA), an amount similar to that previously documented in healthy children. Only three of the 19 subjects averaged less MVPA than the recommended amount (at least 60 min/day). MVPA levels were significantly higher on weekdays than weekend days (P= 0.006). Overall, boys engaged in significantly more MVPA than girls (P= 0.029). MVPA time was negatively correlated with age (r =-0.80) and age at diagnosis (r =-0.87). No trend between MVPA and time off treatment or body mass index was identified. CONCLUSIONS: Survivors of childhood ALL appear to be engaging in similar amounts of MVPA as those of the healthy children and are meeting recommended levels of physical activity.