Lohan was rushed to a hospital Thanksgiving Day with chest pains and had been scheduled for surgery, but further evaluation revealed additional clots that require treatment before he could go under the knife.
TMZ said Lohan would undergo a course of medication and was penciled in for surgery on Monday.
Lohan last week pleaded guilty in Tampa to battering his girlfriend in 2010 and was ordered to complete a four-month, domestic-violence treatment program.
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