His condition remained unchanged, the government said in a statement Monday.
"Treatment has been administered permanently and rigorously, and the patient is supporting it," the statement said.
While reports from CNN affiliate Globovision included discussions of political uncertainty Wednesday, state television broadcasts showed presidents and foreign ministers arriving in Venezuela, walking on a red carpet at the airport as soldiers stood guard.
Meanwhile, Venezuelan opposition leaders called on officials from other countries to cancel their plans to attend.
Henrique Capriles, who lost to Chavez in October's presidential election, said he had reached out to foreign ministries to ask them not to send representatives.
"They are trying to put presidents from the Americas in a political rally," he said.