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.
BREAKING DOWN 'Ask'. This is the opposite of bid, which is the price a buyer is willing to pay for a security, and the ask will always be higher than the bid. The terms bid and ask are used in nearly every financial market in the world covering stocks, bonds, currency and derivatives. An example of an ask in the stock market would be $5.24 x 1,000 which means that someone is offering to sell 1,000 shares for $5.24. RELATED TERMS.