John Murphy's Cardiology Compass has a no-frills guide to links about cardiology. The Electrophysiology page has some brief definitions for arrhythmias and a bit about research interests. Mark Levinson founded and moderates the site. There's a page to submit database search requests and read the posted answers. Of special note are the sections for the non-medical public, including The Learning Center which provides education about cardiovascular diseases.
Heart failure remains the major cause of death and research is needed into novel drug approaches.
The Cardioreparation Web Index links with various resources helpful in research into heart failure and facilitates contacts with researchers and practitioners. Heart Surgery Online is a set of pages by Dr S. Sivasubranmanian. He is also the editor of The Mining Company's Heart Disease page . Each CHD has the medically accepted abbreviation as well as a short description and a link to detailed definitions of the disease. Some of the CHD's listed have a link to a diagram that graphically shows the disease or defect.