His body was discovered around 11.30am outside the three-storey building which he owned known as 'Vijay Mahal' located along Jalan Tengku Hassan.
He leaves behind widow Anucia Tharumaratnam and two sons.
Below is the report from Malaysiakini
The police are investigating the matter and Gerakan's top leaders are currently at the Seremban Hospital where the remains had been taken.Picture: Courtesy of the Star
In a statement later, Gerakan said Vijayaratnam had suffered a heart attack and party sources dismissed rumours that foul play was involved.
"Vijayaratnam passed away this morning due to heart attack. This is a sad news to Gerakan, the Barisan Nasional and to the country," read the statement.
"He was a leader of principle respected by many and a role model for the young people inside and outside of Gerakan. May God bless his family and give them strength."
Meanwhile, Gerakan president Dr Koh Tsu Koon expressed shock and sadness over Vijayaratnam's sudden demise.
"We lost a committed comrade and close friend," he said in a statement.
Describing Vijayaratnam as a dedicated and loyal leader of Gerakan, Koh said:
"We pay tribute to a true Malaysian. Vijayaratnam frequently contributed articles to the media to articulate the party's ideology and stand on various issues of national concern.
"Vijayaratnam, whose father is a former DAP leader and a one-term parliamentarian for Seremban Barat, joined Gerakan in 1980.
Vijayaratnam was appointed senator in 2002 and served for two years, from 2006 to 2008, as parliament secretary of the Plantation Industries and Commodities Ministry.
Highest ranking non-Chinese in Gerakan
Vijayaratnam - who was a general practitioner based in Seremban - was the highest ranking non-Chinese leader in Gerakan.
In the party polls last month, he retained his vice-president post by coming in second. The highest vote-getter was former Youth chief Mah Siew Keong (1,153 votes), followed by Vijayaratnam (678) and former Penang Youth chief Huan Cheng Guan (568).
Highly-fancied Malay candidate Dr Asharuddin Ahmad (537) failed to make the cut.
Party observers said that Vijayaratnam was able to win the post twice because he was known as the president's manVijayaratnam was chairman of party's International Affairs & Ethnic Relations Bureau and head of Gerakan branch in Sungai Ujong, Negri Sembilan.
He was also a member of the National Economic Consultative Council, a fellow of the Royal Society of Health in London, and an honorary fellow of the Indian College of General Practitioners in New Delhi, India.