THE OBJECTIVE OF THIS STUDY was to investigate the associations among clinical, impedance cardiography, echocardiography, and chest roentgenography data in diagnosis of pulmonary hypertension for patients with cardiovascular and pulmonary diseases. METHODS Pulmonary artery pressure was measured by impedance cardiography method in 181 patients: 80 patients with cardiovascular pathology when pulmonary hypertension was determined by echocardiography, 69 patients with cardiovascular pathology when pulmonary hypertension was not observed using echocardiography, 19 patients with pulmonary pathology when pulmonary hypertension was determined by echocardiography, and 13 patients with pulmonary pathology when pulmonary hypertension was not observed using echocardiography. Clinical data, parameters of impedance cardiography, echocardiography, and chest roentgenography were evaluated. RESULTS Pulmonary hypertension (impedance cardiography) was diagnosed by computed mean blood pressure in pulmonary artery with a sensitivity and specificity of 72% and 90%, respectively, and by systolic blood pressure with a sensitivity and specificity of 96% and 90%, respectively. A mathematical model of binary regression was developed with a 96.7% accuracy to diagnose pulmonary hypertension. The most important parameters of impedance cardiography were systolic blood pressure in pulmonary artery and systolic time index. CONCLUSIONS Mean and systolic blood pressures in the pulmonary artery, assessed by a computerized impedance cardiogram, are diagnostically valuable parameters. In diagnostic algorithms of pulmonary hypertension, the following features can be used: atrial fibrillation; thrombosis of deep veins; dyspnea; cyanosis; accent of II tone at the auscultation point of the pulmonary valve; systolic murmur at the tricuspid valve area; increased diameter of the pulmonary artery more than ≥ 18 mm on chest x-ray; increased diameter of the right ventricle; systolic blood pressure in the pulmonary artery and systolic time index measured by impedance cardiography method.