Pulmonary hypertension is a severe multietiological disease largely resistant to treatment. Biopsy is often necessary to establish differential diagnosis. In pulmonary hypertension transbronchial pulmonary biopsy is contraindicated and open lung biopsy is the method of choice. In our paper we report about experimental results in animals and first clinical data on a new biopsy technique (percutaneous transluminal biopsy, PTB) providing access to histology in pulmonary hypertension without the need of surgery. In a subset of animals pulmonary hypertension was produced experimentally. In addition, we carried out the PTB in patients with bronchial carcinoma. Our preliminary results demonstrate that sufficient material could be gained for the histologic evaluation of pulmonary parenchyma and in pulmonary vessels. No complications have been noted so far.