What is the difference between svt and a fib? can you have both?

Two different issues: Svt is a common usually "solitary " form of short circuit that can happen at any age, often in women .There several forms of svt . Now afib is a different can of worms - this is a more complex arrhythmia that may be related to structural heart abnormalities or endocrine problems . There are patients that need blood thinners. Patients can have both but it's not common. Definitely visit your doc.