A 13 year-old female is brought to the emergency room because she has been spitting up blood stained sputum for the last three days. She is having shortness of breath even with a short walk and passing out with exertion. Often her skin, lips and nails turn a bluish tone. Physical examination shows cyanosis in the lips and digital clubbing in both upper extremities. On auscultation, first heart sound is normal and P2 is markedly accentuated; a soft holosystolic murmur is heard in the tricuspid area and a long diastolic murmur is heard in the pulmonary area. A chest x-ray showed right ventricular enlargement with filling in of the retrosternal air space; dilated central pulmonary arteries, abrupt attenuation and termination of peripheral pulmonary artery branches. ECG showed normal voltages and no beat-to-beat variation; it revealed the right atrial enlargement and right ventricular hypertrophy with a rightward axis. Echocardiogram corroborates the findings observed on chest x ray and ECG. Patient could not finish the 6-minute walk testing (6MWT). Which of the following is most likely found in this patient?
