Soft tissue impact characterisation kit (STICK) for ex situ investigation of heart rhythm responses to acute mechanical stimulation

Effects of mechanosensitive ion channels on ventricular electrophysiology: experimental and theoretical models

“…The early favourite, gadolinium, is highly non‐specific (Pascarel et al 1998) and precipitates almost completely in physiological buffers (Caldwell et al 1998). Streptomycin, an efficient MSC blocker in isolated cells at concentrations near 40 μ m (Gannier et al 1994), is not very selective at higher concentrations (Belus & White, 2002), and may be inefficient for acute interventions in native tissue (Cooper et al 2006). This inability of streptomycin to acutely block MSC in situ will have been a prerequirement for human prescription of this drug as an antibiotic; otherwise vestibular side‐effects of the drug would probably be more acute and more common.…”

“…More recently, an impactor has been developed that can be used to subject isolated hearts and/or tissue fragments to controlled and localized mechanical stimulation. This soft tissue impact characterization kit offers independent control over impact timing and energy, projectile mass and speed, as well as impact surface and location (Cooper et al 2006). It also provides accurate information on mechanical probe deceleration parameters, which is crucial for quantitative characterization of probe–tissue interactions.…”

“… ECG from a Langendorff‐perfused guinea‐pig heart, illustrating the electrophysiological response to controlled left ventricular mechanical impact during the T wave The stimulus (arrow) causes a short run of ventricular fibrillation (VF), preceded and followed by normal sinus rhythm (NSR). Reproduced with permission from Cooper et al (2006). …”

Spiral-wave dynamics in ionically realistic mathematical models for human ventricular tissue: the effects of periodic deformation

“…Therefore, we have not attempted to study how different mechanical stimuli, other than the PD we consider, initiate or affect spiral-waves in our model; studies of other mechanical stimuli lie beyond the scope of our paper. In Weise et al (2011) it has been noted that both electrical and mechanical stimuli can cause the formation of a pacemaker in cardiac tissue; and mechanical stimuli can translate the mechanical energy into an electrical stimulus, as argued in Janse et al (2003) and Cooper et al (2006). We use a monodomain description for cardiac tissue; and we do not use an anatomically realistic simulation domain (Panfilov and Keener, 1995; Trayanova and Tice, 2009), muscle-fiber orientation, and transmural heterogeneity (Majumder et al, 2011b, 2012); the inclusion of these features lies beyond the scope of this study.…”

Mechanical triggers and facilitators of ventricular tachy-arrhythmias

“…This might suggest that local effects are relevant even in the setting of Commotio cordis . Our own preliminary optical mapping studies demonstrate focal activation during nontraumatic epicardial impacts ( 46 ) , applied to Langendorff-perfused rabbit hearts using a local impactor ( 47 ) (Fig. 22.4 ).…”