Implanted bronchial isolation devices and methods

A flow control device suitable for implanting in a bronchial passageway, comprising:

• a valve defining a variable-sized mouth through which air can flow through the valve to regulate air flow when implanted in the bronchial passageway, wherein the mouth increases in size in response to air flow in a first direction and the mouth decreases in size in response to air flow in a second direction and
• wherein the valve includes coaptation regions comprising a first lip and a second lip that are connected at opposed corners that are parallel and define the mouth therebetween, the mouth being open when the coaptation regions are at least partially spaced apart from one another, wherein the first and second lips are at least partially spaced apart in a parallel fashion to keep the mouth open when exposed to no air flow, wherein the coaptation regions move away from one another to increase the size of the mouth to a size larger than the size of the mouth when exposed to no air flow in response to air flow in the first direction and move toward one another to decrease the size of the mouth in response to air flow in the second direction.