Houston's a city of great giving and the CultureMap Charity Challenge, presented by Yellow Cab, aims to highlight that. CultureMap selected 12 deserving nonprofits to compete for a grand prize as they all raise awareness for worthy causes. CultureMap is highlighting all the charities during the voting. Today: The American Heart Association.

The American Heart Association is the nation’s oldest and largest voluntary organization devoted to fighting cardiovascular diseases and stroke. Founded in 1924 by six philanthropic cardiologists, the organization now includes more than 22.5 million volunteers and supporters.

The nonprofit funds innovative research, pushes for stronger public health policies and provides lifesaving tools and information — they're the nation's leader for CPR education training — to save and improve lives.

The American Heart Association helps people understand the importance of healthy lifestyle choices. They provide science-based treatment guidelines to health care professionals to help ensure the best treatment for every patient. The group also helps educate lawmakers, policy makers and the public as they advocate for changes to protect and improve the health of every community.

The organization holds several annual events locally including the Heart Ball — which raised nearly $60 million nationwide last year alone — and the Heart Walk to help raise awareness and funds to fight cardiovascular disease and stroke.

Vote now for The American Heart Association — or one of the other worthy local nonprofits — in the CultureMap Charity Challenge.