Therefore, can be acute or chronic as follows:

Acute aortic regurgitation In acute AR, as may be seen with acute perforation of the aortic valve due to endocarditis, there will be a sudden increase in the volume of blood in the left ventricle. The ventricle is unable to deal with the sudden change in volume. The filling pressure of the left ventricle will increase. This causes pressure in the left atrium to rise, and the individual will develop pulmonary edema. Severe acute aortic regurgitation is considered a medical emergency. There is a high mortality rate if the individual does not undergo immediate surgery for aortic valve replacement.Acute AR usually presents as florid congestive heart failure, and will not have any of the signs associated with chronic AR since the left ventricle had not yet developed the eccentric hypertrophy and dilatation that allow an increased stroke volume, which in turn cause bounding peripheral pulses. On auscultation, there may be a short diastolic murmur and a soft S1. S1 is soft because the elevated filling pressures close the mitral valve in diastole.Chronic aortic regurgitation If the individual survives the initial hemodynamic derailment that acute AR presents, the left ventricle adapts by its eccentric hypertrophy and dilatation with a subsequent compensated volume overload. The left ventricular filling pressures will revert to normal and the individual will no longer have overt heart failure. In this compensated phase, the individual may be totally asymptomatic and may have normal exercise tolerance.
Contact must then be transferred to the mouth and swallowed. It is especially prevalent amongst those in regular contact with bodies of fresh water including recreational water such as swimming pools. Other potential sources include insufficiently treated water supplies, contaminated food, or exposure to feces. The high resistance of Cryptosporidium oocysts to disinfectants such as chlorine bleach enables them to survive for long periods and still remain infective. Some outbreaks have happened in day care related to diaper changes.The following groups have an elevated risk of being exposed to Cryptosporidium:
Child care workers
Parents of infected children
People who take care of other people with cryptosporidiosis
International travelers
Backpackers, hikers, and campers who drink unfiltered, untreated water
People, including swimmers, who swallow water from contaminated sources
People who handle infected cattle
People exposed to human feces through sexual contactCases of cryptosporidiosis can occur even in cities that have a properly de-contaminated water supply. In a city with clean water, it may be that cases of cryptosporidiosis have other origins. Testing of water, as well as epidemiological study, are necessary to determine the sources of specific infections. Cryptosporidium is causing serious illness  more frequently in immunocompromised than in apparently healthy individuals. It may chronically sicken some children, as well as adults who are exposed and immunocompromised. A subset of the immunocompromised population is people with AIDS. Some sexual behaviors can transmit the parasite directly. Life cycle
Cryptosporidium spp. exist as multiple cell types which correspond to different stages in an infection (e.g., a sexual and asexual stage).