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.
Definition: The ask or offer price is the lowest price that a seller is willing to accept for a stock or other security. The ask size will specify the number of shares the seller is willing to sell at that ask price. Example: When you get a quote on a stock or security you will often see the Last Trade Price and the current Bid/Ask prices. For example, Google might have a Last of $700.75 and be Bid $700.50 and Ask $701.00.