Dr. Jonathan Arn Hemphill, MD

Dr. Hemphill practices at Dignity Health Medical Group - Sierra Nevada, a Service of Dignity Hea in Grass Valley, California.

Dr. Hemphill's NPI, 1952405326, was assigned on September 7, 2006. Dr. Hemphill graduated from St. George's University School of Medicine in 1982. Dr. Hemphill's California license number on file is A44304.

Dr. Hemphill's primary practice is Dignity Health Medical Group - Sierra Nevada, a Service of Dignity Hea, at 280 Sierra College Dr, Grass Valley, CA 95945 in Nevada County. The practice phone is (530) 274-6727.

Dr. Hemphill's primary practice is Dignity Health Medical Group - Sierra Nevada, a Service of Dignity Hea in Grass Valley, California. Dr. Hemphill is also affiliated with Dignity Health - Sierra Nevada Memorial Hospital. The medical group on file is Mercy Medical Group. Dmand AI also links Dr. Hemphill to 4 more hospitals and 1 group practice or clinic, each named with a free account.

Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Hemphill practices, 6 sites in all. Vendor and product names are available with a free account.

Interventional cardiology is Dr. Hemphill's primary specialty in the NPI Registry, under taxonomy code 207RI0011X. Dr. Hemphill is board certified in cardiovascular disease by the American Board of Internal Medicine. Dmand AI has Dr. Hemphill's licenses on file in 3 states: California, Hawaii and New Mexico.

Dmand AI lists angioplasty, cardiac catheterization, pacemaker or defibrillator implantation and pacemaker replacement among the conditions Dr. Hemphill treats.

CMS data shows 3,988 Medicare services from Dr. Hemphill across 23 procedure codes in 2024, for 1,146 Medicare patients. Medicare paid $229,195 for them.

CMS counts 1,146 Medicare patients who saw Dr. Hemphill in 2024. The largest group is 75 to 84, with 486 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 17% are also on Medicaid. Their average risk score is 1.42, where 1.00 is the Medicare average.

Across all payers, Dmand AI patient panel data puts Dr. Hemphill's median patient age at 76, with 47% women.

In 2024, Dr. Hemphill wrote 6,337 Medicare Part D claims for 772 patients. 77% of them were for generic drugs. CMS names the drug for 6,069 of them, across 70 drugs with 11 or more claims each, at $2,085,849 in total drug cost. In 2023, CMS named 5,459 claims across 63 drugs.

CMS publishes a Merit-based Incentive Payment System (MIPS) score of 100 out of 100 for Dr. Hemphill for performance year 2024, reported through an alternative payment model (APM). Dr. Hemphill accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS lists Dr. Hemphill as offering telehealth.

Pacemaker insertion or repair: 1 to 10 procedures (CMS shows small counts as a range)

CMS Open Payments shows 745 general payments to Dr. Hemphill from 44 drug and device companies from 2016 to 2025. Food and beverage make up the largest share, 76% of the total. Abbott Laboratories paid the most, $3,025.

Dmand AI lists 3 awards for Dr. Hemphill.

Dr. Hemphill graduated from St. George's University School of Medicine in 1982. Dr. Hemphill is a member of ACC.

Dr. Hemphill is in network with 8 carriers, including Aetna, Elevance and Blue Cross Blue Shield of Michigan. Medicare plans come from the most carriers, 8. Check the plan with the practice before a visit.