Press TV - Iranian stem cell scientist Dr. Masoud Soleimani, who returned home last week following his release from US prison, has been taken to hospital with a heart condition.

Soleimani�was rushed to Tehran Heart Center on Sunday after suffering�from heart problems as he was about to head to Press TV headquarters for a news conference.

He�underwent medical checks in hospital and was released later.

The scientist returned home last Saturday following a prisoner swap with the US, which saw American citizen Xiyue Wang released by Iran.

Soleimani suffered from several health problems which aggravated during his incarceration in the United States.

The researcher�� who works in stem cell research, hematology and regenerative medicine � was on a sabbatical when he was arrested by US authorities upon arrival in Chicago a year ago and transferred to a prison in Atlanta, Georgia.

In a meeting with Isfahan Governor General Abbas Rezaei on Wednesday, Soleimani recounted his ordeal during his time behind bars, saying he had been held �in a cell with another person� next to �murderers and drug traffickers.�

The scientist said American �justice� exists only in Hollywood films, adding that his jail wardens had told other prisoners that he was a �terrorist and the inmates were scared to approach me.�

Soleimani had been invited by the Mayo Clinic in Minnesota to lead a research program there, but he was arrested upon arrival and secretly imprisoned without trial by the FBI on October 7, 2018.

FBI authorities reportedly arrested him on charges he had violated trade sanctions by trying to have biological material brought to Iran.

The charges related to September 2016 when Soleimani had seized on two former students' plans to travel from the US to Iran as a chance to get recombinant proteins used in his research for a fraction of the price he�d pay at home. Recombinant proteins are found fundamentally in every medical testing and biological research laboratory.

The students were arrested while departing the United States because they were carrying five vials of the proteins. They were charged in a court and released after posting bail because they held US citizenship.

However, about four months before Soleimani's visit, an attorney in Atlanta had secured his indictment on June 12, 2018, just a month after President Donald Trump withdrew the US from the Iran nuclear deal and announced sanctions under Washington�s �maximum pressure� on Tehran.

Soleimani had been fully unaware of such an indictment when he flew to the US. Moreover, Washington had claimed that maximum pressure did not target the supply of medicine and other humanitarian necessities.