Pathology General 53e20937 Sudden death, right sided hea failure (cor pulmonale or cardiovascular collapse occur when ? A Small pulmonary embolism B Massive pulmonary embolism C 60% or more of pulmonary aery is obstructed with emboli D End aery obliteration High-Yield Explanation Ans. is 'c' i.e., 60% or more of pulmonary aery is obstructed with emboli