Overview

Cardiology is the study of the heart and blood vessels. Since heart disease is the leading cause of death globally, it is a critical field focusing on the mechanics, electricity, and plumbing of the cardiovascular system.

Core Idea

The core idea is circulation. The heart is a pump that must beat 100,000 times a day without stopping to deliver oxygen and nutrients to every cell. Cardiology keeps that pump running.

Formal Definition

A medical specialty dealing with disorders of the heart as well as parts of the circulatory system. It includes diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease, and electrophysiology.

Intuition

The heart is a mechanical pump with an electrical starter.

  • Plumbing: Arteries can get clogged (heart attack).
  • Electricity: The timing can get out of sync (arrhythmia).
  • Mechanics: The valves can leak or the muscle can get weak (heart failure).

Examples

  • Myocardial Infarction (Heart Attack): A blockage in a coronary artery kills heart muscle.
  • Hypertension (High Blood Pressure): The “silent killer” that strains the heart and damages vessels over time.
  • Atrial Fibrillation: An irregular, rapid heart rate that causes poor blood flow.

Common Misconceptions

  • Misconception: Heart attacks always hurt the chest.
    • Correction: Especially in women, symptoms can be subtle (nausea, fatigue, jaw pain).
  • Misconception: Heart disease is a “man’s disease.”
    • Correction: It is the #1 killer of women as well.

Applications

  • Intervention: Angioplasty and stenting to open clogged arteries.
  • Prevention: Managing diet, exercise, and cholesterol to prevent disease.

Criticism and Limitations

  • Lifestyle vs. Pills: Modern cardiology is amazing at saving lives in emergencies, but the root cause (lifestyle) is harder to fix with a pill.

Further Reading

  • The Heart: A History by Sandeep Jauhar
  • Braunwald’s Heart Disease (Textbook)