Plastic surgeons first carried out the elongation, which involves making an incision to loosen a ligament at the base of the penis.
They then began the enlargement and had planned to inject two fluid ounces of fat cells.
Yet, before they finished the injection, his heart began racing, his oxygen levels fell, and his blood pressure dropped, and he then suffered a heart attack, reports the Journal of Forensic Sciences.
Doctors performed CPR and sent the man to an emergency room, but he died less than two hours later.
The patient, who had mild asthma, but otherwise no past medical history, died from a fat embolism, the report's authors state.
This occurs when fat tissue passes into the bloodstream and lodges within the blood vessels of the lung and other sites, resulting in respiratory failure.
The paper states that 'penile elongation and enlargement is considered to be a simple and safe procedure' but warns that complications may be higher when both procedures are combined.
While this is the first reported death from this kind of surgery, experts say it often leads to other serious problems.
'It's a completely useless procedure that never works and disfigures men, and could kill you,' urologist Tobias Kohler of the Mayo Clinic in Rochester, Minnesota told BuzzFeed News.
He said: 'This is the worst case, but there are lots of other horrible consequences, from disfigurement to permanent erectile disfunction to even worse.'
Disappointing results
Furthermore, one expert has warned that the risks are not worth taking and results are often disappointing.
Sexual medicine consultant Professor Kevan Wylie said studies that followed men up over a longer time suggest disappointing results, with complications including disfigurement, scarring, lumpiness and infection.
He says the use of biodegradable frames has had better results than fat injection, reports the NHS.
Professor Wylie said: 'The problem with injecting fat is that over time, the body will re-absorb the fat which can result in a return to the penis' original size.'
He adds that penis enlargements can result in an average gain in length to the flaccid penis of 2cm, but there will be no change to the size of the erect penis.
Furthermore, the erect penis will not point as high as before the surgery because the ligament which was cut no longer offers support.
'A lot of men who have this treatment don't truly appreciate this loss of angle,' says Professor Wylie.
'It can make sex quite uncomfortable. You've got to do a lot more manoeuvring with your partner. The advantage of a 2cm gain in flaccid length is far outweighed by the loss of angle of erection.'
