There is disclosed a method performed by a User Equipment, UE, for Hybrid Automatic Repeat Request, HARQ, retransmission of data in a multi-antenna wireless communication system. The method comprises, receiving Acknowledgement/Negative Acknowledgement, ACK/NACK, feedback information relating to data transmitted on two streams, and performing, upon rank reduction where only one stream is available for transmission, retransmission of data on a cancelled stream over the remaining stream. There is furthermore disclosed a UE configured for performing the method. A transmission method together with an arrangement for a UE is also disclosed.