Michael Stuart Hanna M.D.

An arrhythmia is the violations of the frequency, rhythm, and sequence of heart contractions.Why do arrythmias occur?...

IntroductionDoctors who specialize in the diagnosis and treatment of conditions or diseases of the cardiovascular system (the heart and blood vessels) are called heart doctors or cardiologists. These specialists are trained to identify, treat, and help prevent heart issues. There are also different...

Our heart rate is automatically controlled by the autonomic nervous system (ANS) that has two divisions: sympathetic and parasympathetic. The part of the ANS that is responsible for raising a person’s heart rate through the sympathetic plexus is the sympathetic division. The parasympathetic...

Atrial fibrillation - also known as AF or a-fib - is a medical condition that affects the rhythm of the heart. Problems that affect the rhythm of the heart cause a condition known as arrhythmia. This condition often causes irregular blood flow. It is quite common, with more than 200,000 cases in the...

What is a bubble study?A bubble study is a type of echocardiogram, which is the ultrasound of the heart. An echocardiogram is done to visualize the heart and its surrounding areas. Better images of the heart can be produced when a “contrast” is used during the echocardiogram. In a bubble study,...

Heart palpitations, although it feels like a scary experience, are not always a sign of something serious. These palpitations are harmless but there are some instances when it could be a signal to a serious heart disease, especially if it is associated with other symptoms. This article explains...