The ladder diagram (a 100+ year history)

Area of Science:

• Cardiology
• Medical Imaging

Background:

• The ladder diagram (or laddergram) is a widely used graphical method for illustrating cardiac arrhythmia mechanisms.
• It visually separates atrial and ventricular electrical activity and highlights key cardiac nodes.

Observation:

• Ladder diagrams originated in the late 19th century, initially for pulse timing, and were adapted for electrocardiograms in 1920.
• Their application has evolved to explain the generation and propagation of cardiac electrical impulses.

Findings:

• The report reviews the historical origins, development, and inherent limitations of ladder diagrams.
• Case examples demonstrate their predictive power for arrhythmias like atrioventricular nodal reentrant tachycardia and evolving depictions for atrial flutter.

Implications:

• Ladder diagrams excel at depicting impulse conduction abnormalities but are less effective for impulse formation issues.
• The enduring utility of the ladder diagram underscores its robust design for analyzing diverse arrhythmogenic mechanisms.