Actually, psoriasis also causes those splinter hemorrhages as well. I had them and it turned out to be a part of my psoriasis, not heart involvement:
"This study, conducted by researchers in Ontario, Canada, examined 188 people with psoriatic arthritis to see if specific nail changes were tied to specific joint symptoms. Almost everyone in the study—172 patients—had some kind of fingernail psoriasis on at least one nail, according to the findings.
Patients with blood spots under the nail, also known as splinter hemorrhages, tended to have higher numbers of swollen joints, while patients with other kinds of nail psoriasis—including vertical ridges on the nail; red spots in the white, crescent-shaped area at the root of the nail; and crumbling nails—had higher numbers of tender joints, researchers reported."
/www.psoriasis.org/advance/nail-changes-psa-symptoms-go-hand-in-hand While I agree that it's always a good thing to be sure your heart is checked out, there are plenty of other things that can cause the same issues.