(a) As used in this Code section, the term "health care insurer" means any insurer which issues, delivers, issues for delivery, or renews an individual or group plan, policy, or contract for health care services issued, delivered, issued for delivery, or renewed in this state by a health care corporation, health maintenance organization, preferred provider organization, accident and sickness insurer, fraternal benefit society, hospital service corporation, medical service corporation, or other insurer or similar entity. It shall not, however, include a policy of insurance designed, advertised, and marketed to supplement basic health care coverage for hospital, medical-surgical, or major medical expenses so long as said supplemental insurance contract provides for payment directly to the insured.

(b) Any other provision of law to the contrary notwithstanding, if a covered person provides in writing to a health care provider, whether the health care provider is a preferred provider or not, that payment for health care services shall be made solely to the health care provider and be sent directly to the health care provider by the health care insurer, and the health care provider certifies to same upon filing a claim for the delivery of health care services, the health care insurer shall make payment solely to the health care provider and shall send said payment directly to the health care provider. This subsection shall not be construed to extend coverages or to require payment for services not otherwise covered.