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Pressure doesn't necessarily equal increased vascular resistance. Pulmonary resistance regulation mainly increases in areas of hypoxia, and decreases in well-oxygenated area's to send blood to well ventilated areas, nothing to do with an acute MI. In fact in MI there is vasodilation of apical capillaries and the V/Q ratio will approach 1 to accommodate the extra blood. In this patient, you can see his systemic blood pressure is low yet his systemic vascular resistance is high (due to sympathetic constriction of vessels in response to low CO). I just thought of it like how in normal resting state ventilation is wasted at the apex so in a volume overloaded state that extra blood could go up to the apex.