Vējonis is awake and can talk to the doctor on duty, Pauls Stradins Clinical University Hospital spokeswoman Lāsma Sile told LETA.
The president is currently in an intensive care ward so medical staff quickly to follow his state of health. After the type of operation Vējonis underwent, patients usually spend about a week in the intensive care unit, before being transferred to the Department of Cardiology, Sile added.
Sile explained that it is too early to predict how long the president will remain in the hospital, and even after he eaves hospital a rehabilitation period will be necessary.
Under such circumstances Saeima speaker Inara Murniece - currently deputizing for Vējonis - could face an extended period exercising his powers, likely to be months rather than weeks.
The hospital spokeswoman also emphasized that despite his position, Vējonis was not given any special treatment and the decision to operate quickly was based on purely clinical considerations.
As previously reported, doctors on Wednesday conducted emergency surgery, during which they managed to eliminate the source of a septic infection of the heart valves and replaced one valve with an artificial valve.
Further information about Vejonis' recovery and how long it is likely to take before he is back in the saddle, is expected later on Thursday.
Meanwhile, as reported by LTV on Wednesday, flowers and get well cards have arrived by the dozen at the hospital as members of the public wish the best for the popular 49-year-old head of state.
In a midday update, the office of the president repeated that he was stable and said his recovery time would depend on how his body responded to treatment.
"The recovery process is individual and depends on the body's ability to cope with the post-operative condition and infection," the statement said adding that a "calm and supportive environment" was necessary to aid recovery.
The statement also called on people to donate blood to help other cardiac patients.