Pathological Inferior Q Wave: Prevalence in the Spanish Population Over 40 Years and Association with Heart Disease

Introduction: Inferior pathological Q wave is an electrocardiographic finding frequently found. There are no recent studies in Spain about its prevalence and its association or not with structural heart disease in general population.
Objectives: to analyze the prevalence of inferior pathological Q in the Spanish population over 40 years as well as its role as marker or predictor of heart disease.
Methods: A cross-sectional study endorsed by the Spanish Society of Cardiology over the Spanish population ≥ 40 years was performed. Two-stage random sampling was used. First stage units were primary care physicians randomly selected at every Spanish province. Second stage units were 20 randomly selected persons drawn from every participating physician’s assigned population. Finally, 8,343 consented to participate and completed the study protocol that included a 12-lead-EKG. There was centralized reading of the EKGs that were evaluated by two trained cardiologists. In case of disagreement a third cardiologist was consulted. Final diagnosis was reached by consensus. Pathological inferior Q wave was defined when duration were > 40 ms and size ≥ 25% of R wave in at least two of the three inferior leads (II, III and aVF).
Results: Mean age was 59.2 years, 52.4 % female. We obtained 172 cases with inferior pathological Q wave. (Weighted prevalence 2%, CI 95% 1.6-2.4). Multivariate analysis showed that independent predictors of pathological inferior Q wave were: male gender, coronary heart disease and central obesity (Table 1).

Conclusions: Inferior pathological Q wave is frequently found in our population (2%) and its isolated presence is associated not only with coronary heart disease but with central obesity also.