Cardiac allograft vasculopathy (CAV) is a progressive type of coronary artery disease in people who have had a heart transplant. As the donor heart has lost its nerve supply there is typically no chest pain, and CAV is usually detected on routine testing. It may present with symptoms such as tiredness and breathlessness.It arises when the blood vessels supplying the transplanted heart change in structure. They gradually narrow and restrict its blood flow, subsequently leading to impairment of the heart muscle or sudden death. In addition to the same risk factors for coronary artery disease due to the build up of plaque, CAV is more likely to occur if the donor was older or died from explosive brain death, and if there is cytomegalovirus infection. Its mechanism involves immunological (innate and adaptive) and nonimmunological factors, with distinct features on histological samples of coronary arteries. Other major causes of death following heart transplantation include graft failure, organ rejection and infection.Diagnosis is by regular follow-up and monitoring of the transplanted heart for early signs of disease. Tests include coronary angiography, intravascular ultrasound, dobutamine stress echocardiography, positron emission tomography, computed tomographic angiography (CT angiography) and several biomarkers.Statins and aspirin are commenced early after transplantation and on detection of CAV. Medications including sirolimus and everolimus can slow disease progression. A repeat heart transplantation may be required.CAV affects around half of heart transplant recipients within 10 years. It contributes to the death of 11-13% one year from heart transplantation.
Affected teeth usually appear as brownish-blue, brown or yellow. Translucent “opalescence” is often one of the characteristics to describe teeth with DD-2. In some cases teeth might show slightly amber coloured but in most of the cases permanent teeth are unaffected and appear normal regardless of colour, shape and size. Dental X-rays are the key to diagnose dentine dysplasia, especially on permanent teeth. Abnormalities of the pulp chamber is the main characteristic to make a definitive diagnosis.In the primary teeth, coronal dentin dysplasia may appear similar to Dentinogenesis Imperfecta type II (DG-II) but if abnormalities features appear to be more pronounced in the permanent teeth, then consider changing the diagnosis to DGI-II instead of DD-2. Radiographic features
In coronal type, teeth show normal roots containing enlarged pulp with abnormal extensions towards the roots, which is often described as “thistle tube” shaped on dental radiographs. As well as this, numerous pulp stones can be often found in the pulp chambers due to abnormal calcifications. In primary teeth, the pulp chamber is usually completely obliterated but in permanent teeth, the pulp may become partially obliterated after eruption. Histological features
There are a few studies and proposals that were designed to explain the pathogenesis of DD but the main reason of the cause still remains unclear in the dental literature. Logan et al., suggested that dental papilla is the cause of abnormal root growth or development. They also proposed that calcification of multiple degenerative foci within the papillae reduce the growth and eventually leads to pulpal obliteration.