Testing single muscle cell threads in heart biopsies from people with cardiomyopathies

Effect of mutations associated with dilated and hypertrophic cardiomyopathies on myofibril mechanical properties and contractility

Cardiomyopathies are diseases that affect the heart muscle. They are frequently caused by genetic mutations, which are passed down through families. Cardiomyopathies can be very serious, causing enlargement or thickening of the heart, heart failure or sudden cardiac death. BHF-funded researchers have been pioneers in the discovery of genes that cause these conditions. This has enabled families to benefit from genetic screening, but there is still a great deal to discover about how genetic mutations go on to cause these conditions. The culprit genes often affect the proteins that make up myofibrils. These are the tiny thread like structures packed into heart muscle cells that, together, enable the heart to pump powerfully. Dr Vikhorev and colleagues have developed equipment that can measure contraction and how it is controlled in single myofibrils, which can be prepared from pieces of human heart taken from patients with cardiomyopathies. Now they will use these techniques to test myofibrils from people with genetic mutations that cause different types of cardiomyopathies. They will assess how the genetic mutations affect the ability of each myofibril to contract and extend, how stiff it is, and how the contraction is controlled. This will help us to understand how mutations cause the symptoms of these cardiomyopathies, and give information for developing more effective treatments or cures.