A helicopter pilot had a NMAC with an air carrier aircraft near MIA.

Narrative

Approaching MIA's Class B airspace from the northeast; I called MIA Tower to get a clearance to enter MIA's airspace. Requested southbound I-95. Was cleared as requested. Shortly after I requested; 'helicopter X; westbound Dolphin (which is south of the airport at MIA International); south of your runways at all times.' It was approved as requested. I went westbound Dolphin found the scene; made right orbits around it; and then came to a hover facing into the wind eastbound (still south of the runways but close to the extended centerline of the departure end of Runway 12) for about 4-5 minutes when I heard the hissing noise of an airliner. Looked out in the direction of the noise which was to my right only to see that a little ahead and higher than me was what I believe to be a passenger-carrying airliner. Shortly after; I heard the pilot of the other aircraft tell the Tower that 'he had almost hit the helicopter.' The Tower replied that 'he would relay the message and that I should have been north of his path.' The other pilot then said that 'if he would have made the left turn as instructed; he would have hit me' and then proceeded on saying that 'he didn't feel too good about the whole thing.' I was never advised by the Controller to stay clear of the extended departure end of Runway 12 for departing traffic or advised of any departing traffic.