Acute aortic regurgitation (AAR) is a potentially fatal ailment, that entails the malfunction of the aortic valve. It has a number of etiologies, including infective and iatrogenic ones. This condition is more common in males.
Acute aortic regurgitation (AAR) is a disease where the leaflets of the aortic valve fail to come together and close properly, leading to the backflow of blood. It has several causes, which may be infective, such as bacterial endocarditis, trauma-related, most often blunt trauma to the chest, inflammatory (nonbacterial endocarditis), and aortic dissection . Less commonly, AAR is iatrogenic following cardiac surgery, or due to penetrating chest trauma. In addition, dysfunction of prosthetic valves may be a factor.
AAR may present with clinical features similar to those of heart failure or severe infection . This may make the correct diagnosis of AAR more difficult, however, it is important that it is rightfully diagnosed, as it is an emergency. Furthermore, its prognosis is much poor than the chronic form of the disease  .
The main symptoms of AAR are vascular and in keeping with cardiac failure. Consequently, patients may experience dyspnea, chest pain, and general body weakness. The onset of AAR features such as chest pain and dyspnea is sudden . Signs of the disease commonly include tachycardia, cyanosis, pulsus alternans, crepitations in the lungs indicating pulmonary edema and hypotension and peripheral vasoconstriction leading to cool extremities. Additionally, S1 may be absent, S3 may be present, with a concurrent murmur (Austin Flint murmur). The severity of symptoms varies. Cardiogenic shock may ensue, with multi-system organ failure.
Acute aortic regurgitation is diagnosed clinically, combining history and physical examination findings.
Diagnostic imaging modalities include:
Biochemical studies may be chosen by the physician, according to the patient's clinical features and suspected etiology. These may include full blood count, blood culture, rheumatic makers, and specific organ function tests.
The severity of AAR can be determined by the vena contracta, measured via color Doppler  . A value of more than 6mm indicates severe disease. This measurement is highly sensitive and specific.