WILLIS KO, MD appears in the CMS NPPES registry as a Interventional Cardiology Physician provider holding MD credentials at 6810 STATE ROUTE 162 STE 102B, MARYVILLE, IL, 62062, with a listed phone of (618) 288-4076. NPI 1215465307 was issued on 06/01/2017. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what KO most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 166 prescription claims written by this provider, covering 55 Medicare beneficiaries and totaling roughly $17K in drug spend, split 12% brand-name and 88% generic by claim count. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Interventional Cardiology Physician is a narrow specialty nationwide, with 3,382 enrolled providers across 53 states and an average of 2,984 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.