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What is the sinoatrial (SA) or sinus node?

ANSWER

The sinoatrial (SA) or sinus node is a node in the upper right section of your heart that monitors your body's need for blood. It acts like a natural pacemaker. It's the main control and source of each heartbeat. It can speed up your heart rate when you need it, like when you exercise or get sick, or even when you feel happy.

SOURCES:

Kenneth Ong, MD, associate chief of cardiology, director of Cardiology Fellowship Program, director of Cardiac Noninvasive Imaging Laboratory, Brooklyn Hospital Center. William G McDonald, MD, FAAEM, consulting staff, Department of Emergency Medicine, Arkansas Heart Hospital.

Kathryn L. Hale, MS, PA-C, medical writer, eMedicine.com. Alan D Forker, MD, program director of cardiovascular fellowship, professor of medicine, Department of Internal Medicine, University of Missouri at Kansas City School of Medicine.

Francisco Talavera, PharmD, PhD, senior pharmacy editor, eMedicine.

Anthony Anker, MD, FAAEM, attending doctor, Emergency Department, Mary Washington Hospital, Fredericksburg, VA.

Reviewed by Suzanne R. Steinbaum on August 24, 2017

SOURCES:

Kenneth Ong, MD, associate chief of cardiology, director of Cardiology Fellowship Program, director of Cardiac Noninvasive Imaging Laboratory, Brooklyn Hospital Center. William G McDonald, MD, FAAEM, consulting staff, Department of Emergency Medicine, Arkansas Heart Hospital.

Kathryn L. Hale, MS, PA-C, medical writer, eMedicine.com. Alan D Forker, MD, program director of cardiovascular fellowship, professor of medicine, Department of Internal Medicine, University of Missouri at Kansas City School of Medicine.

Francisco Talavera, PharmD, PhD, senior pharmacy editor, eMedicine.

Anthony Anker, MD, FAAEM, attending doctor, Emergency Department, Mary Washington Hospital, Fredericksburg, VA.

Reviewed by Suzanne R. Steinbaum on August 24, 2017

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What are ventricular and supraventricular heart arrhythmias?

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