Related Experiment Video

Updated: May 19, 2026

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
10:17

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System

Published on: April 11, 2025

Sinus rhythm electrocardiogram identification of basal-lateral ischemic versus nonischemic substrate in patients with

Brian P Betensky1, Marc W Deyell, Wendy S Tzou

  • 1Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.

Journal of Interventional Cardiac Electrophysiology : an International Journal of Arrhythmias and Pacing
|August 14, 2012
PubMed

Insights

Electrocardiogram (ECG) patterns can differentiate nonischemic cardiomyopathy (NICM) scar from myocardial infarction (MI) scar. Specific ECG findings like QRS fragmentation and Q waves help identify unique scar-based ventricular tachycardia (VT) substrates.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Imaging

Background:

  • Sinus rhythm (SR) electrocardiogram (ECG) features in patients with nonischemic cardiomyopathy (NICM) and ventricular tachycardia (VT) are known.
  • ECG characteristics distinguishing nonischemic VT substrate from prior myocardial infarction (MI) are not well-defined.

Purpose of the Study:

  • To identify specific ECG differences between patients with basal-inferolateral scar due to NICM and those with prior MI.
  • To develop a diagnostic algorithm for differentiating these scar types using surface ECG.

Main Methods:

  • Comparison of SR/atrial-paced ECGs from patients with NICM basal-inferolateral scar (n=25) and inferior/inferolateral MI (n=30).
  • Analysis of surface QRS complexes, excluding patients with bundle branch block or ventricular pacing.
  • Development and prospective validation of a diagnostic algorithm using multivariate analysis.

Main Results:

  • NICM group showed smaller R amplitude in leads I, II, III and greater S amplitude in leads II, III, V6 compared to MI group.
  • Inferior Q waves were less common in NICM (24%) than MI (87%).
  • Lateral QRS fragmentation was observed in 20% of NICM patients, distinguishing them from MI patients. A three-step algorithm achieved 100% sensitivity and 77% specificity for NICM.

Conclusions:

  • Lateral lead QRS fragmentation, absence of inferior Q waves, and a lead V6 S/R ratio ≥0.25 on SR ECG can distinguish basal-lateral scar from NICM versus prior MI.
  • Surface ECG is valuable for identifying unique scar-based VT substrates.
Abstract

More Related Videos

Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction06:57

Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction

Published on: January 31, 2019

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis18:11

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

Published on: December 28, 2012

Related Concept Videos

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias01:16

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias

Arrhythmias are disturbances in the heart's rhythm that lead to abnormal heartbeats. These irregularities can originate from different parts of the heart and are classified based on their origin and nature.
Types of Arrhythmias
Sinus Node Arrhythmias
Sinus Bradycardia: Originating from the sinoatrial (SA) node, sinus bradycardia involves slower impulses, resulting in a heart rate of less than 60 beats per minute (bpm). Causes include sleep, vagal stimulation, beta-blockers, hypothyroidism, and...
Dysrhythmias IV: Characteristics of Bradyarrhythmias01:18

Dysrhythmias IV: Characteristics of Bradyarrhythmias

Bradyarrhythmias are cardiac rhythm disorders characterized by a slower-than-normal heart rate, typically defined as fewer than 60 beats per minute. Some of which are discussed here:Sinus BradycardiaSinus bradycardia presents a heart rate lower than 60 beats per minute, with a regular rhythm originating from the SA node. The ECG typically shows normal P waves preceding each QRS complex, a normal PR interval (0.12 to 0.20 seconds), and a normal QRS duration (0.06 to 0.10 seconds).First-Degree AV...
Dysrhythmias II: Classification of Tachyarrhythmias01:28

Dysrhythmias II: Classification of Tachyarrhythmias

Tachyarrhythmias are a type of dysrhythmia where the heart rate exceeds 100 beats per minute. Here are some common types of tachyarrhythmias:Sinus TachycardiaSinus tachycardia originates from increased impulses from the sinus node, leading to an elevated heart rate. It is often triggered by stress, fever, or exercise.Patients may experience palpitations, a sensation of a racing heart, dizziness, and chest discomfort.Causes and Risk Factors: Common causes include physical exertion, emotional...
Dysrhythmias III: Characteristics of Dysrhythmias01:29

Dysrhythmias III: Characteristics of Dysrhythmias

Dysrhythmias, also known as arrhythmias, are irregular heart rhythms that result from abnormal electrical activity in the heart, affecting its ability to circulate blood efficiently. Tachyarrhythmias, a subset of dysrhythmias, are characterized by abnormally fast heart rates exceeding 100 beats per minute. Here are some types of tachyarrhythmias with their distinct ECG features:Sinus Tachycardia:Sinus tachycardia presents a regular heart rhythm with an increased rate of 101-180 beats per minute.
Dysrhythmias V: Evaluating Dysrhythmias01:30

Dysrhythmias V: Evaluating Dysrhythmias

Dysrhythmias, also known as arrhythmias, are disturbances in the heart's rhythm that range from benign to life-threatening. A thorough evaluation is crucial for appropriate management and involves a comprehensive medical history, physical examination, and various diagnostic tests.Medical HistorySymptoms: Collect detailed information on palpitations, dizziness, syncope, chest pain, and fatigue. Note their onset, frequency, and triggers.Previous Cardiac Issues: Document any history of heart...
Electrocardiogram01:29

Electrocardiogram

An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...