Re: How can you have a heart attack without blockage?
Electrophysiology of the heart requires potassium, calcium and sodium to transmit electrical impulses to contract heart muslce and lack of impulse relaxes heart muscle. The process is referred to polarization and depolarization of the heart chambers.
Also there are channels for the impulse to pass called the left and right bundle branch. Sometimes the channel blocks and the impulse becomes disorganized and/or disrupted. Or the source fails to generate a signal
If the impulses are disrupted, disorganized or fail to be generated from the source, there can be a heart attack. The attack can happen when the impulse is disorganized causing the heart to beat so fast there is inadequate chamber filling and low cardiac output depriving blood/oxygen to the heart. If there is a disruption or no source signal, the heart will not receive oxygen. These are some examples resulting from a electrophysiological aspect causing a heart attack.
There is an inconsistency related to the event referred to as a heart attack. A heart attack, medically referred to as myocardio infarction, is lack of oxygen causing heart muscle to die. If the blood work is positive for an MI, that would indicate necrosis of heart muscle and a damaged heart.
A panic attack can cause weak heart to fail, but that would be from a neurocirculatory perspective that deals with nerves and the vascular system.