Dimon suffered an “acute aortic dissection” according to a statement to shareholders.
Dimon, 63, was described as “awake, alert and recovering well” following the surgery.
Daniel Pinto and Gordon Smith, co-presidents and co-chief operating officers of the financial giant, will lead the company during Dimon’s recuperation.
JPMorgan shares fell $5.88, or 4.9%, to $113.97 in regular trading Thursday amid a broad pullback in U.S. markets on coronavirus fears. The stock fell $1.97, or 1.7%, to $112 in after-hours action.
Dimon has been CEO of JPMorgan since the end of 2005.
Pinto began his work at Manufacturers Hanover in 1983 in Buenos Aires. The company was later acquired by Chemical Bank, which later merged with Chase Manhattan before being acquired by JPMorgan in 2000.
Smith started at JPMorgan Chase in 2007 after 25 years at American Express. He took on his current role in 2012.
Elsewhere, financial stocks fell Thursday amid a broad market sell-off driven by rising fears of the coronavirus outbreak spreading throughout the United States as California declared a state of emergency and new cases were reported in New Jersey and Maryland.
The financial select SPDR ETF XLF fell $1.34, or 4.82%, to $26.45.
The S&P 500 financials sector index fell 22.43, or 4.88%, to 437.12.
JPMorgan is a holding in Jim Cramer's Action Alerts PLUS member club