Guidant products treat both abnormally fast and slow heartbeats

In doing so, Brussels ruled that the US firm must sell a number of businesses to ensure competition was not reduced in certain product areas.

Guidant makes cardio-vascular devices such as defibrillators and pacemakers.

Johnson, best known for its baby products, hopes Guidant will broaden its business beyond drugs sales.

Competition commitments

Like other leading pharmaceutical firms, Johnson - based in New Jersey - is facing the expiry of patents on several of its drugs.

The launch of cheaper, generic versions of drugs has eaten into the revenues of leading drug companies, forcing them to diversify.

The $25.4bn acquisition of Guidant, whose headquarters is in Indiana, was first announced in December.

The Commission was required to approve the deal because both companies do significant business in the 25-member union.

"In light of the commitments given by Johnson & Johnson, the Commission has concluded that the transaction would not significantly impede effective competition in the European economic area or a significant part of it," it said in a statement.

Johnson will be required to divest certain businesses operating in smaller areas of the cardio-vascular device market.