Heart stoppers: winning images from British Heart Foundation competition – in pictures

Shortlisted: Dragonfly by Arianna Fornili and Franca Fraternali at King’s College London. This image shows the simulated motion of a two-headed fragment of myosin, a molecule vital for contraction found in heart muscle cells. Different time frames of this dragonfly-shaped molecule are shown here simultaneously, with red spikes indicating the direction of motion Photograph: Franca Fraternali/King’s College London/The British Heart Foundation

Shortlisted: The Forgotten Majority by Katja Gehmlich and Sina Lenski, University of Oxford. The heart is not just made up of beating cells. In fact the majority of cells are 'cardiac fibroblasts'. The internal scaffolding of fibroblasts is stained red in the picture Photograph: Katja Gehmlich and Sina Lenski/University of Oxford/The British Heart Foundation

Shortlisted: Rough Road to Regeneration by Andrea Caporali, University of Bristol. This scanning-electron microscope image shows the stress response of a blood vessel cell in a condition such as diabetes. Understanding the stresses that diabetes places on the cardiovascular system may help researchers treat some of its complications Photograph: Andrea Caporali/University of Bristol/The British Heart Foundation

Shortlisted: At the Heart of It by Emma Kay at Queen Mary, University of London. Receptors called 'Toll-like' on white blood cells sense invading microbes and kickstart the immune response. This image shows white blood cells with Toll-like receptors (pink) migrating from a small vein (turquoise) in response to the presence of bacteria Photograph: Emma Kay/Queen Mary/University of London/The British Heart Foundation

Shortlisted: Spaghetti Junction by Graeme Birdsey and Dr Anna Randi at Imperial College London. This microscope image of cells lining blood vessels reveals the proteins that support and shape them: elongated actin stress fibres (green) and the tangled web of microtubules (red) Photograph: Graeme Birdsey and Dr Anna Randi/Imperial College London/The British Heart Foundation

Highly commended: Killer Cholesterol by Dr Yichuan Wen and Dr David Leake, University of Reading. Immune cells called 'foam cells' are found in the arteries of people with atherosclerosis. The white specks are cholesterol, which can cause changes that lead to heart attacks and strokes Photograph: Dr Yichuan Wen and Dr David Leake/University of Reading/The British Heart Foundation

Highly commended: What Sets your Heart on Fire? by Dr William Moody, University of Birmingham. This is an MRI scan of the heart of a healthy kidney donor. MRI is sensitive enough to detect early, treatable scar formation in the heart that may occur after donating a kidney Photograph: Dr William Moody/University of Birmingham/The British Heart Foundation

Highly commended: At the Heart of a Cell by Dr Andrew Cobb, King’s College London. A heart-shaped nucleus in a cell from vascular smooth muscle, which helps give blood vessels their shape. The green specks show regions of DNA damage, which could explain the unusual shape of the nucleus Photograph: Dr Andrew Cobb/King’s College London/The British Heart Foundation

Mending Broken Hearts winner: Caught in the Net by Dr Jana Koth, University of Oxford. This is the developing heart of a two-day old zebrafish embryo. The green cells are heart muscle cells, and the red and blue show components that make up the muscle. The early heart tube has started to loop. It consists of two sections: the large, thin atrium (where blood flows in) and the smaller, thicker ventricle (where blood leaves flows out) Photograph: Dr Jana Koth/University of Oxford/The British Heart Foundation

Image of the Year: The Broken Heart by Gillian Gray, Megan Swim and Harris Morrison, University of Edinburgh. This image reveals the 3D structure of an adult mouse heart. It was created using a technique called 'optical projection tomography', which can be used to assess the extent of injury and healing after a heart attack Photograph: Dr Gillian Gray, Megan Swim and Harris Morrison/University of Edinburgh/The British Heart Foundation