Palpitations are uncomfortable sensations of the heart beating hard, rapidly, or irregularly. Some types of palpitations are benign, while others are more serious. Palpitations are diagnosed by taking the patient history and by performing an EKG or heart monitoring along with blood tests. An electrophysiology study may also be performed. Treatment of palpitations may include lifestyle changes, medication, ablation, or implantation of a pacemaker. The prognosis if palpitations depends on the underlying cause.
Your brain focuses on some alleged thread, for instance, a very scary thought that was floating somewhere at your subconscious.  Your thalamus – the part of the brain responsible for regulating consciousness, sleep and alertness – transfers that information to your amygdala – the part of the brain responsible for emotional reactions, decision-making and memory – which marks it as “danger” and sends a signal to your sympathetic nervous system, activating the fight-or-flight response.
Shortness of breath and chest pain are the predominant symptoms. People experiencing a panic attack may incorrectly attribute them to a heart attack and thus seek treatment in an emergency room. Because chest pain and shortness of breath are hallmark symptoms of cardiovascular illnesses, including unstable angina and myocardial infarction (heart attack), a diagnosis of exclusion (ruling out other conditions) must be performed before diagnosing a panic attack. It is especially important to do this for people whose mental health and heart health statuses are unknown. This can be done using an electrocardiogram and mental health assessments.

During the day if she was out, the attack felt “like my head suddenly weighed a thousand pounds and my chest would get really heavy. It literally felt like something was pulling me down. I would usually have to head home immediately.  I would then experience foggy vision where it …actually looked like there was fog in the air. I also experienced double vision and parts of my body—like my neck or one arm or one entire side of my face– would go totally numb.”
One of the most important things you can do is to listen to your family member or friend talk about the things in his/her life that are sources of stress. A first instinct might be to offer advice or ideas for a "quick fix". However, simply accepting your friend's stress levels can help them deal with their anxiety, knowing that they can rely on you as a source of support even when their symptoms might be tough to watch. Studies show that social support from family and friends can be one of the strongest protective factors against debilitating levels of anxiety.

Characterized by a suite of symptoms that persist for at least three days and up to one month after a traumatic experience (same diagnostic criteria for "trauma" as listed above). The specific symptoms of the disorder vary across individuals, but a common feature is intense anxiety in response to re-experiencing symptoms (e.g., recurrent intrusive recollections of traumatic event) of the trauma.
Social anxiety disorder (previously called social phobia): People with social anxiety disorder have a general intense fear of, or anxiety toward, social or performance situations. They worry that actions or behaviors associated with their anxiety will be negatively evaluated by others, leading them to feel embarrassed. This worry often causes people with social anxiety to avoid social situations. Social anxiety disorder can manifest in a range of situations, such as within the workplace or the school environment.
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