Samoan medical authorities are investigating why two patients died, after open-heart surgery carried out in Apia last month, by a volunteer surgical team from New Zealand.

They were among 14 people operated on by the team over a 10-day period.

The general manager of Samoa's national health services, Dr Stanley Dean, says a similar set of operations carried out last year was successful, and the complications among this year's patients were unusual.

The news website 'Samoa alive' quotes Dr Dean as saying that complications from surgery usually occur in the first two days after surgery, not after the patients have been sent home.

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