At this point, some blood of the " previous cycle's systole " is " still flowing out " of the ventricles through the semilunar valves, due to the inertia of the moving blood column, which overcomes the " higher pressure " in the aorta / pulmonary trunk with respect to the pressure in the ventricles.
22.
If you've been stabbed in the chest, then the things that will cause you to die are 1 ) blood loss due to perforation of the heart, great vessels ( aorta, pulmonary trunk etc ) and / or lungs; 2 ) Hypoxia, as a result of either 2a ) transection of the trachea, or either bronchus in the mediastinum; 2b ) interruption of blood supply to the lungs.
