This is a condition in which the heart fails, and instead of being able to pump all the blood forward, some of the blood backs up into the lung, the lungs fill up with blood, and that's why you have shortness of breath.
To je stanje u kojem srce zakazuje i umjesto da je u mogućnosti da tjera svu krv naprijed, krv se vraća natrag u pluća, pluća se pune krvlju i zato ostajete bez zraka.