John M. Miller MD FACC


Antiarrhythmic Medicines

Antiarrhythmic medicines may be used to return an irregular heartbeat (arrhythmia) to its normal rhythm, prevent an arrhythmia, or control the heartbeat during an arrhythmia. These drugs work mostly by slowing the heart rate or by helping the heart muscle tissue become stable. Many antiarrhythmic medicines have side…

Implantable Cardioverter-Defibrillator (ICD)

An implantable cardioverter-defibrillator (ICD) is a battery-powered device that can fix an abnormal heart rate or rhythm and prevent sudden death. The ICD is placed under the skin of the chest. It’s attached to one or two wires (called leads). Most of the time, these leads go into the heart through a vein. An ICD is…

Heart Rhythm Problems: Symptoms

Heart rhythm problems, called arrhythmias, can cause a few types of symptoms. These symptoms happen because the heart isn’t beating regularly or may not be pumping blood as well as normal. Some of these symptoms include palpitations, lightheadedness, fainting, and shortness of breath. Palpitations Having palpitations…

Catheter ablation for atrial fibrillation

How the heart’s electrical system works In a normal heart, the sinoatrial (SA) node triggers the electrical impulse, causing the upper chambers (atria) to contract. The signal travels through the atrioventricular (AV) node to the atrioventricular bundle, which divides into the Purkinje fibers that carry the signal and…

Marcapasos permanente

Un marcapasos es un pequeño dispositivo alimentado a pila que envía pequeños impulsos eléctricos para hacer que el corazón lata a un ritmo regular y una velocidad normal. Un marcapasos consta de un generador de pulsos y una pila que crean los impulsos eléctricos. La mayoría de los marcapasos tienen cables (derivaciones)…