An apparatus, comprising: a catheter (28, 100) adapted to insert an annuloplasty device into a coronary sinus of a heart in a living subject, said catheter being operative for actuating said annuloplasty device in an operative location in said coronary sinus, wherein said catheter has ultrasound transducers adapted to transmit first acoustic signals toward said heart and receiving second acoustic signals that are echoes of said first acoustic signals, and wherein said catheter has a position sensor adapted to transmit signals indicative of location and orientation coordinates of said catheter; a location positioning system including an ultrasound driver for driving said transducers and an image processor for receiving electrical signals from said ultrasound transducers of said catheter and processing said signals to construct an anatomic image of a portion of said heart, said location positioning system being operative for registering said operative location of said annuloplasty device with said anatomic image while said annuloplasty device is being inserted by said catheter, said location positioning system being operative for locating points of interest on a left circumflex coronary artery of said heart; and a Doppler-flow imaging sensor adapted to obtain a blood flow image for evaluating blood flow within said left circumflex coronary artery concurrently with deployment of said annuloplasty device in said coronary sinus, wherein said apparatus is configured to register said blood flow image and said catheter position with the previously acquired two-dimensional or three-dimensional anatomic image of the heart whereby an operator can determine whether deployment of said annuloplasty device may compromise blood flow through said left circumflex coronary artery. a catheter (28, 100) adapted to insert an annuloplasty device into a coronary sinus of a heart in a living subject, said catheter being operative for actuating said annuloplasty device in an operative location in said coronary sinus, wherein said catheter has ultrasound transducers adapted to transmit first acoustic signals toward said heart and receiving second acoustic signals that are echoes of said first acoustic signals, and wherein said catheter has a position sensor adapted to transmit signals indicative of location and orientation coordinates of said catheter; a location positioning system including an ultrasound driver for driving said transducers and an image processor for receiving electrical signals from said ultrasound transducers of said catheter and processing said signals to construct an anatomic image of a portion of said heart, said location positioning system being operative for registering said operative location of said annuloplasty device with said anatomic image while said annuloplasty device is being inserted by said catheter, said location positioning system being operative for locating points of interest on a left circumflex coronary artery of said heart; and a Doppler-flow imaging sensor adapted to obtain a blood flow image for evaluating blood flow within said left circumflex coronary artery concurrently with deployment of said annuloplasty device in said coronary sinus, wherein said apparatus is configured to register said blood flow image and said catheter position with the previously acquired two-dimensional or three-dimensional anatomic image of the heart whereby an operator can determine whether deployment of said annuloplasty device may compromise blood flow through said left circumflex coronary artery.