A Transvenous Pacemaker is a cardiac pacing device that delivers electrical impulses to the heart through leads placed in the heart via the veins. It is a therapy and procedure used to treat clinically significant bradycardia (slow heart rate) and certain conduction disorders. It is most commonly used in acute care as temporary pacing and in long-term care as a permanent pacemaker system. It sits at the intersection of cardiac electrophysiology, emergency stabilization, and chronic rhythm management.

A Subcutaneous ICD is an implantable cardioverter-defibrillator (ICD) placed under the skin without leads inside the heart or veins. It is a device therapy used to treat life-threatening ventricular arrhythmias such as ventricular fibrillation (VF). It belongs to the domains of electrophysiology, sudden cardiac death prevention, and cardiac device implantation. It is commonly used for selected patients who need defibrillation protection but do not require pacing therapies.

Cardiac Lead Placement is the process of positioning insulated wires (“leads”) that connect an implanted cardiac device to the heart. It is a procedural concept in electrophysiology and cardiothoracic care, most commonly used for pacemakers, implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) systems. The goal is to reliably sense cardiac electrical activity and deliver pacing or defibrillation therapy when needed. It is discussed in acute care, outpatient cardiology, and long-term device follow-up settings.

Cardiac resynchronization therapy with defibrillator (CRT D) is an implantable cardiac device used in selected patients with heart failure and electrical dyssynchrony. It combines biventricular pacing (resynchronization) with an implantable cardioverter-defibrillator (ICD) function. CRT D is a therapy and device-based intervention in electrophysiology and heart failure care. It is commonly used in patients with reduced left ventricular ejection fraction (LVEF) and a widened QRS complex on electrocardiogram (ECG).

Device Implantation is the placement of a medical device inside the body to diagnose, monitor, or treat disease. In cardiology, it most often refers to implantable devices that support cardiac rhythm, circulation, or structural heart function. It is a procedural therapy and sometimes a diagnostic strategy. It is commonly used in arrhythmias, heart failure, and selected structural heart and vascular conditions.

Lead Extraction is the removal of one or more implanted cardiac device leads from the body. It is a procedural therapy used in cardiac electrophysiology and cardiothoracic care. It is most often discussed in the context of cardiac implantable electronic devices (CIEDs), such as pacemakers and implantable cardioverter-defibrillators (ICDs). It is commonly performed for infection, lead malfunction, or to regain venous access for new leads.

A Mapping Catheter is a specialized intracardiac catheter used to record and localize electrical activity inside the heart. It is a device used in cardiac electrophysiology, most commonly during an electrophysiology study (EPS) and catheter ablation. It helps clinicians identify arrhythmia mechanisms and target sites for therapy. It is routinely used in labs that evaluate supraventricular tachycardia (SVT), atrial fibrillation (AF), atrial flutter, and ventricular tachycardia (VT).

Electrophysiology Study is an invasive cardiac diagnostic test that evaluates how electrical signals start and travel through the heart. It is performed in an electrophysiology (EP) lab using catheter-based recordings from inside the heart. It is most commonly used in patients with suspected or known arrhythmias such as supraventricular tachycardia (SVT) or ventricular tachycardia (VT). It can be purely diagnostic or combined with catheter ablation as part of treatment planning.

Cardiac Arrhythmogenic Focus is a term for a localized area of heart tissue that initiates abnormal electrical impulses. It is a physiology and electrophysiology concept used to explain certain cardiac arrhythmias (abnormal heart rhythms). It is commonly discussed when interpreting an electrocardiogram (ECG) and when planning electrophysiology (EP) testing or catheter ablation. It helps clinicians describe “where the rhythm is starting” rather than only describing what the rhythm looks like.

Cardiac Complications are new or worsening heart-related problems that occur during the course of another illness, injury, or medical intervention. They are discussed across cardiology, internal medicine, emergency care, surgery, and critical care. They can involve the myocardium (heart muscle), valves, coronary arteries, pericardium, or the conduction system. The term is commonly used in hospital medicine, perioperative care, and when monitoring high-risk therapies.