Electrocardiographic poor R wave progression III. The normal variant

Area of Science:

• Cardiology
• Electrocardiography

Background:

• Poor R wave progression (PRWP) is observed in various cardiac conditions, including myocardial infarction and hypertrophy.
• PRWP is also frequently noted in individuals without apparent heart disease, prompting investigation into its underlying causes.

Purpose of the Study:

• To investigate technical and constitutional factors contributing to PRWP in apparently normal individuals.
• To differentiate true PRWP from artifactual changes caused by lead placement or respiratory variations.

Main Methods:

• Prospective analysis of ECGs in 68 hospitalized patients to assess the impact of precordial lead misplacement and respiratory variations.
• Retrospective analysis of ECGs and clinical records of 100 normal individuals and 50 with mitral valve prolapse undergoing cardiac catheterization.

Main Results:

• Superior and inferior lead repositioning created false positive and false negative PRWP, respectively.
• PRWP was identified in 8% of normal individuals (8/100).
• PRWP in normals was not associated with age, sex, body composition, thoracic abnormalities, ECG axis, cholesterol, blood pressure, or mitral valve prolapse.

Conclusions:

• Technical factors like lead misplacement can induce artifactual PRWP.
• A significant proportion of normal individuals exhibit PRWP, likely attributable to normal variations in cardiac electrical signal distribution.