[Diagnosis of pulmonary embolism]

Although clinical assessment (good medical history, identifying patients at risk, recognition of common symptoms and signs, physical findings) and bed-side methods (standard laboratory tests, ECG, chest X-ray, arterial blood gas analysis, echocardiography and compression ultrasound of the lower extremities) for the diagnosis and/or exclusion of pulmonary embolism is highly insensitive and unspecific, the definition of clinical probability (pretest probability) still seems to be of outmost importance. Clinical probability guides initial medical therapy, induces further invasive and non invasive examinations (e.g. perfusion lung scan, spiral CT, gadolinium-enhanced magnetic resonance pulmonary angiography, contrast pulmonary angiography) and is still the final determinant in case of conflicting results of imaging modalities.