Cardiac tamponade can occur due to: 1  Dissecting aortic aneurysm (thoracic) 2  End-stage lung cancer. 3  Heart attack (acute MI) 4  Heart surgery. 5  Pericarditis caused by bacterial or viral infections. 6  Wounds to the heart.
Bid vs. ask and why yields matter. With many investments, the concept of bid and ask applies to prices. The bid price is what a buyer is willing to pay for a security, while the ask price is what a seller is willing to accept for the same security. The difference between those two numbers is known as the bid-ask spread, and in general, the narrower that spread, the more liquid the market is.
Bid price. A bid price is the highest price that a buyer (i.e., bidder) is willing to pay for a good. It is usually referred to simply as the bid. In bid and ask, the bid price stands in contrast to the ask price or offer, and the difference between the two is called the bidâask spread. An unsolicited bid or purchase offer is when a person or company receives a bid even though they are not looking to sell.