A 65 y.o. patient complains of shortness of breath, cough with red foamy sputum, feeling of air deficit, fear of death. On examination: orthopnea, pale skin, acrocyanosis, cold sticky sweat. Rough breathing sounds, in inferior-posterior arias on both sides - small and medium moist rales. BR - 40/min. Heart sounds are distinctly muffled. On the cardiac apex - gallop rhythm. What is the most probable preliminary diagnosis?