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.
There s the bid price, which is the price another investor would be willing to buy shares of a stock for. And then there s the ask price, which is the price you d have to pay if you wanted to buy the stock. The ask price is generally higher than the bid price, but sometimes they can be virtually the same. Most financial Web sites usually display both the bid and ask prices but give the ask price more prominence. Bid and ask prices aren t unique to stocks. It s no different than a car. If you go to a car dealership and offer to sell your car, you ll be given a bid price. Similarly, if you want to buy the car you ll almost certainly receive a higher offer price.