Russia informed the US embassy that Whelan had undergone the surgery on Thursday.
Whelan, a US national who also holds British, Canadian and Irish passports, has been in custody since he was detained in a Moscow hotel room in December 2018.
Two US Marines were killed on March 8 which advising and accompanying Iraqi Security Forces during a mission to eliminate ISIS.
The 71-year charade, whether wittingly or not, impugning the legitimacy of Jerusalem as the capital of Israel, had been put to rest.
The spirits of US marines, both living and departed, heroes all, were not the only ones in that great celebratory hall.
Thousands of Marines were on high alert to respond within two hours should violence break out.