Sensitivity and Specificity of ECG in Diagnosis Left Ventricular Hypertrophy in Comparison with Echocardiography in Hypertension and Diabetic Patients
Authors: Deiratani George , Hammad Anis 
Published: June 2023

Abstract
Background: Electrocardiography (ECG) is an important diagnostic tool for detecting left ventricular hypertrophy (LVH) in patients with primary arterial hypertension and diabetes. While ECG has low sensitivity, it is highly specific for diagnosing LVH, although this varies depending on age, gender, body mass index (BMI), and smoking status. Echocardiography (Echo) is also an important method for diagnosing LVH and is often used as a reference for comparison with ECG results.
Objective: To investigate the sensitivity and specificity of ECG in comparison to cardiac Echo, according to age, gender, body mass index, and smoking status.
Materials and Methods: We performed a cross-sectional study that included 83 hypertensive patients attending the cardiac clinics of Al-Mujtahid Hospital. For each patient, we collected their information and recorded it on a form. Then, we performed ECG and cardiac Echo to measure the Sokolow-Lyon Criteria and the mass of the left ventricle. We then used graphical analysis of statistics to determine the sensitivity and specificity of the ECG in detecting LVH compared to the left ventricular mass (LVM) calculated by Echo, which was used as the reference measure.
Results: The sensitivity of ECG was 25% in men compared to 20% in women, with a P-value of less than 0.001. Similarly, the specificity of ECG was 87% in men and 76% in women, with a P-value of less than 0.001, which is statistically significant. In smokers, the sensitivity of ECG was 27% compared to 19% in non-smokers, with a P-value of less than 0.001. Furthermore, the specificity of ECG was 89% in smokers compared to 76% in non-smokers, with a P-value of less than 0.001, which also indicates a statistically significant difference.
In terms of sensitivity and specificity distribution according to BMI, the sensitivity of the BMI group between 18 and 24.9 was 25%, compared to 23% for the BMI group between 25 and 29.9, and 19% for the BMI group between 30 and 34.9. The P-value was 0.001, indicating a statistically significant difference. Similarly, the specificity of the BMI group between 18 and 24.9 was 88%, compared to 83% for the BMI group between 25 and 29.9, and 77% for the BMI group between 30 and 34.9, with a P-value of 0.001, which is also statistically significant.
Regarding sensitivity and specificity distribution by age, the sensitivity was 26% in the age group 40-49, 25% in the age group 50-59, and 23% in the age group 60-69, with a P-value of 0.53, which is not statistically significant. Similarly, the specificity by age was 89% in the age group 40-49, 87% in the age group 50-59, and 87% in the age group 60-69, with a P-value of 0.41, which is not statistically significant.
Conclusions: our study found that the sensitivity and specificity of ECG were higher in males compared to females, and tended to be higher in individuals with lower BMI and in non-smokers compared to smokers. However, age did not have a statistically significant effect on sensitivity and specificity.