A medical system comprising a guiding catheter having an inflation lumen. The inflation lumen extends within a handle and a shaft of the guiding catheter. An inflatable sleeve has a proximal end and a distal end, with the ends attached to the guiding catheter. A sealed interior portion of the inflatable sleeve is bounded by the inflatable sleeve and the shaft of the guiding catheter, and in fluid communication with a distal port of the inflation lumen. The system further comprises a delivery catheter defining a delivery lumen and configured for sliding engagement within the guide lumen of the guiding catheter.