A day last week, i went about 8 hours without eating, and i began to feel heavy beating in chest,that made it almost difficult to breath.Could this be heart palpitations? and is this dangerous?

Not eating isn't healthy- it stresses the body! If you only skipped food for 1 day, you probably experienced low blood sugar (hypoglycemia)- heart palpitations are a symptom. It isn't dangerous in that it can kill you tomorrow, but skipping meals often is going to cause all kinds of imbalances, and you might have to spend a long time trying to recover/heal your different internal systems. Never go 8 hours without eating again. Heart palpitations are sensations of rapid, fluttering, or pounding heartbeats that are often harmless. But they can be, at times, be a sign of a serious underlying heart problem, such as arrhythmia - abnormal heart rhythm.

I do think that what happened to you was hypoglycemia (an abnormally low level of blood sugar, which is glucose, the main energy source of the body) because you weren't able to eat. And also hypotension (decreased blood pressure) as a result of hypoglycemia.

You definitely had heart palpitations, but it was a signal of your body that you're having low blood sugar and low blood pressure due to decreased food intake.

If you continue to feel abnormalities even though you have food intakes, try to see a doctor. Usually a meal, when taken, is digested within 3 hours, so you'll be able to feel hungry after three hours of initially eating a meal. Try to have non-perishable snacks within reach, such as those granola bars or chocolates, if you're not able to have the time to sit down and eat a full meal due to having a hectic schedule. ^^ Speaking as someone with a well documented heart arrythmia, irregular eating habits can often bring it on. Consistency is one of the best things to avoid palpitations. Always carry a couple granola bars or something with you. As well, overeating or eating high-sodium foods can also cause palpitations, as can excess alcohol. For the most part these palpitations are not dangerous, but you should listen to your body & make sure you're doing the right thing by it. Repeated episodes could mean an arrythmia in the making. If you get them again, and they last for more than an hour or so, go to the ER and let them know what's happening. Don't worry, it's not like having a heart attack and you are not in immediate danger, but it's best to catch the rhythm on an EKG in the ER. That way the doctors will be able to tell you precisely what's happening. Don't worry though...bottom line is just take care of yourself. I live with an irregular heartbeat 23 out of every 24 hours and I'm fine. Good luck to you!