Heart walls of the heart to valves by cartilaginous connections called chordae tendinae. These muscles prevent the valves from falling too far back when they close. During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight. As the heart chambers contract, so do the papillary muscles. This creates tension on the chordae tendineae, helping to hold the cusps of the atrioventricular valves in place and preventing them from being blown back into the atria. Two additional semilunar valves sit at the exit of each of the ventricles. The
The Heart String & How to Pull It 21 March and finishing on 8 April. Pledgers were offered various basic packages that included a physical copy of the album, a digital download of the album, a download of what became the "Chemicals EP", an album-themed T-shirt and an album-themed poster. All of the basic packages included the option to download the album a few days in advance of the physical release. Additionally, there were several special packages that were offered at premium prices. All of the special packages included a digital download of the album. The Heart String & How to Pull It The Heart String & How