What is a maternal electrocardiogram (ECG)?

From the Guidelines

A MAT ECG is a crucial diagnostic tool for assessing cardiac function in pregnant women, and it should be performed using standard 12-lead ECG placement to detect any abnormalities that might affect both mother and baby. The test is particularly important for pregnant women with pre-existing cardiac conditions, those experiencing symptoms like palpitations or chest pain, or when monitoring the effects of medications on cardiac function 1. During pregnancy, normal physiological changes can alter ECG findings, including a leftward axis deviation, slight ST depression, and T-wave inversions, which occur due to the enlarged uterus pushing the diaphragm upward, shifting the heart's position 1.

Key Considerations for MAT ECG

• The test is non-invasive and safe for both mother and fetus 1.
• MAT ECGs provide valuable information about maternal cardiac health that can guide management decisions throughout pregnancy 1.
• Echocardiography is recommended in pregnant patients with unexplained or new cardiovascular signs or symptoms, and cardiovascular magnetic resonance (without gadolinium) should be carried out if additional information is required 1.
• The 2019 UK Confidential Enquiry into Maternal Deaths highlighted the importance of cardiac health during pregnancy, with 48 women dying of heart disease and 34 of venous thromboembolism between 2015 and 2017 1.

Performing a MAT ECG

• Standard 12-lead ECG placement is used, with electrodes attached to the limbs and chest.
• The test should be performed by a qualified healthcare professional who can interpret the results and provide guidance on further management if necessary 1.
• The most recent guidelines and studies, such as those published in 2021, should be consulted to ensure that the MAT ECG is performed and interpreted in accordance with current best practices 1.

From the Research

Echocardiography in Pregnancy

• Echocardiography is a safe and effective diagnostic tool for pregnant women with cardiac symptoms or known cardiac disease 2.
• It is used to assess maternal and fetal risk, and to monitor cardiac condition and valvular function during pregnancy 2, 3.
• Echocardiography can characterize cardiac structural abnormalities and corresponding hemodynamic changes, and identify heart diseases that are poorly tolerated in pregnancy 2.

Indications for Maternal Echocardiography

• The most common indication for initial echocardiography is cardiac symptoms (34.6%) 4.
• History of cardiac disease is the only indication demonstrating a significant association with an abnormal finding on initial echocardiography (odds ratio [OR]: 2.6; p = 0.006) 4.
• Postpartum status, multiparity, and tobacco use are demographic characteristics associated with the identification of abnormal findings on initial echocardiography 4.

Role of Echocardiography in Pregnancy Management

• Echocardiography is the imaging modality of choice for defining, risk stratifying, and monitoring cardiovascular changes throughout pregnancy 3.
• Abnormal echocardiographic findings are associated with changes in clinical management, but do not correlate with adverse obstetric or neonatal outcomes 4.
• Echocardiography serves as a widely available tool for serial monitoring of pregnant women with cardiovascular disease throughout pregnancy and the postpartum period 3.

Assessing Maternal Cardiac Function

• A technique for evaluating maternal cardiac function using diagnostic ultrasound equipment has been developed, allowing for the measurement of maternal left ventricular preload, afterload, contractility, and blood flow 5.
• This technique can be used to screen for abnormal cardiac measurements in pregnant patients with hypertension and fetal growth restriction 5.
• The use of this technique can help clinicians select appropriate hypertensive medication based on the results of the evaluation of the maternal left ventricle 5.