So if you have lines under your nails and other symptoms, including fever or irregular heartbeat, see a doctor immediately, as these could be signs of heart disease.
Yadav explains,"If you have many splinter hemorrhages, it could be an indication of something serious. In the case of heart disease, it's believed that splinter hemorrhages form because of clumps of bacteria traveling through the small blood vessels of the nail bed. This weakens those vessels and makes them more susceptible to hemorrhaging.
and downward-curving fingernails. Clubbing is often caused by heart disease or an infection of the heart's chambers."Clubbing [of the fingernails] refers to an angle of over 180 degrees and it is normally 160 degrees in formal nails," explainsat the University of North Carolina at Chapel Hill."This type of anatomy can be present from birth, but is most commonly seen with osteoarthritis. If it occurs due to heart disease it usually starts in the thumb and index fingers.