Dr. SarahBeth Hartlage, a former associate medical director of the Louisville Health Department, died from heart disease.
The finding by the Orlando Medical Examiner's office comes three months after Hartlage's unexpected death while at a medical conference in Florida.
Hartlage, 36, also suffered from granulomatous lung disease, a condition which affects the body's ability to fight infection and contributed to the death, according to the medical examiner's report.
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An autopsy found significant narrowing of the coronary arteries. Hartlage's death was classified as "natural," the report said.
Her unexpected death shocked the Louisville health community where Hartlage had become the public face of the campaign against COVID-19, helping set up the LouVax drive-thru vaccine site and appearing regularly at weekly press briefings with Louisville Mayor Greg Fischer.
Her colleagues continue to mourn her death but appreciate her many contributions to public health, said Dr. Jeff Howard, Louisville's interim health department director.
Howard praised Hartlage as "one of the city's top leaders during the height of the COVID-19 pandemic," leading thousands of volunteers and helping to build local reponse efforts "from the ground up."
"This loss is felt many magnitudes greater by her family," Howard said. "Our thoughts and prayers continue to be with them, and it is our hope that everyone will provide her family and friends respect and privacy while they continue to grieve her loss."
Fischer in March praised Hartlage's tireless work to make COVID-19 vaccines available.
She "took command of an amazing team of city workers and volunteers to vaccinate tens of thousands of people in a previously unthinkably short amount of time, while also working to ensure vaccines are being distributed equitably throughout the community and communicating facts about their safety in relatable ways to non-medical professionals," Fischer said.
The medical examiner's report took three months to complete because of laboratory analysis and other tests, the office said.
Hartlage died within a day of leaving Louisville for Orlando.
On March 15, Hartlage reported she was excited to be on an early-morning flight to Orlando where she was to speak at a medical conference.
"5AM sweaty airplane selfie can only mean one thing: I am #HIMSS bound!," she said on Twitter, referring to the Health Care Information and Management Systems Society meeting.
Later that day, Hartlage reported in another tweet she stepped in to help with a medical emergency on the plane when a passenger became ill.
Hartlage started an IV on the man at 35,000 feet in the air, working with another doctor and nurse also on the flight. The man was taken to the hospital after landing in Orlando.
“Adrenaline is something I'm very used to,” she told The Courier Journal, “but I have never done it on an airplane and certainly not one in turbulent skies.”
The next day, just hours before she was to speak on "Next Gen Public Health," Hartlage was found dead at her Orlando hotel.
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Hartlage was found at about 11 a.m. March 16 after a family member called the hotel saying they had been unable to reach her, according to the Orange County Sheriff's Office.
A report of the incident stated employees at the hotel found Hartlage unresponsive after the caller asked staff to check on her.
The caller expressed concern that Hartlage recently had been ill with pneumonia and also had other health conditions.
The sheriff's office reported nothing was suspicious about the death.
This story may be updated.
This article originally appeared on Louisville Courier Journal: Louisville Health Department director cause of death: Heart disease