Demand is expected to increase for heart products as we live longer

On Monday, Boston Scientific tabled a $25bn (�14bn) bid, trumping a $21.5bn offer from rival Johnson & Johnson which had been accepted by Guidant.

Guidant said it was willing to give Boston Scientific information about its business, but said its board was not making any recommendation on the bid.

Johnson & Johnson said that it would not be improving its offer.

Analysts said that they had not expected Johnson & Johnson to raise its offer because it had fought to reduce the price it was paying for Guidant.

Older for longer

Johnson & Johnson had initially offered to pay $76 a share but reduced the bid to $63 a share after Guidant had to recall more than 100,000 faulty heart defibrillators.

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Guidant was also investigated over its failure to inform doctors about potential defects in some of its products.

Boston Scientific's offer, which is made up from a mix of cash and company equity, is worth $72 per Guidant share.

Both Johnson & Johnson and Boston Scientific are attracted by the growth potential for heart devices.

They reckon that the products would compliment their existing portfolios of devices such as cardiac stents, which are used to keep coronary arteries open and unclogged.