Improved methods and apparatuses for heart valve repair in a beating heart of a patient utilize an exchangeable heart valve repair system. Heart valve repair system can include a port adapted to be seated in the heart wall and an imaging catheter slidable within the port. The imaging catheter can be selectively locked relative to the port for insertion into the heart and unlocked once the port is seated to allow the imaging catheter to move distally towards target tissue. A deployment catheter slidably disposed in the imaging catheter and a repair cartridge slidably disposed in the deployment catheter can be used to capture the target tissue and deploy a repair device into the tissue after proper capture is confirmed. System elements can be selectively removed from and replaced within port to deploy additional repair devices while port maintains a seal while elements are and are not inserted.
