Diagnosis
The required diagnostics depends on the underlying clinical picture. Whereas in an acute emergency situation such as a heart attack or pulmonary embolism, rapid intervention is required, in other manifestations such as thrombophlebitis, a detailed patient interview is initially possible. It is important to understand that there is no general diagnosis, since the blood clot as such does not represent an independent clinical picture.
It is important that the patient’s medical history (patient interview) identifies existing risk factors that can lead to increased clot formation and that these are eliminated as quickly as possible. These include, for example: nicotine consumption, obesity, high blood pressure, poorly controlled diabetes mellitus, hyperlipidaemia (high blood fat values), diseases of the coagulation system such as APC resistance, pregnancy, oestrogen therapy, old age (over 60) or a positive family history. The latter means that relatives already suffered early on from diseases that were associated with a blood clot (e.g. pulmonary embolism).
If a leg vein thrombosis or pulmonary embolism as a result of a blood clot is suspected, the so-called D-dimers can be determined in the blood. These would be elevated in this case. In many cases the D-dimers are positive even without the presence of leg vein thrombosis, so that an increase in the value alone does not necessarily indicate the presence of a disease.
Furthermore, imaging procedures such as ultrasound are used in diagnostics. A special examination that is very useful in the diagnosis of leg vein thrombosis is compression sonography of the leg veins. An experienced examiner can detect leg vein thrombosis very well in this way.
Procedures such as CT and MRT are also used, but are not part of the standard diagnostic procedure. If blood clots occur at very atypical locations or at a very young age, further thrombophilia diagnosis can be made. This diagnosis is intended to detect diseases that lead to an increased tendency to clot.
These include APC resistance or antiphospholipid syndrome, for example. However, this is a special diagnostic procedure that is based on the underlying tendency to coagulate, also known as thrombophilia. In the diagnosis of myocardial infarction, the ECG, the determination of the so-called cardiac enzymes (troponin T) and the imaging procedures are in the foreground.
The latter are mainly echocardiography, CT examination of the coronary vessels and coronary angiography. CT and cardiac catheterization allow the vessels to be depicted precisely, so that any constrictions present and their localization can be seen. Angiography is another very important procedure that can be used to visualize vascular occlusions caused by blood clots very clearly. In this examination, vessels are made visible with the help of X-rays and contrast medium. Imaging procedures such as angiography, MRI and CT are also very important for the diagnosis of ischemic stroke, which is caused by the occlusion of important brain vessels as a result of a blood clot.