Breath-holding is usually not required for an ordinary ECG, but it may be required for patients with severe obesity, chronic lung disease, and autonomic nervous system dysfunction.
1. Do not hold your breath: In the early stage of breath-holding, it will cause vagus nerve excitation, which has an inhibitory effect on the heart and can slow down myocardial contractility, heart rate and blood pressure. If you hold your breath for too long, the body may become hypoxic, which reflexively causes sympathetic excitation, resulting in a faster heartbeat. Therefore, it is usually not necessary to hold your breath during an ECG examination, so as not to affect the examination results.
2. Breath-holding:
(1) As the fat layer of severely obese people is thicker and the patch is farther away from the heart, which leads to some deviation of the ECG indexes, it may be recommended to hold your breath during the ECG examination.
(2) Since patients with chronic lung disease have a large chest rise and fall when they breathe, it is easy to affect the diagnosis of ECG, so holding a breath may be recommended when doing ECG examination.
(3) Breath-holding in patients with autonomic dysfunction will increase the thoracic pressure, decrease the return blood volume and excite the vagus nerve, which will help the examination.
Doctors will conduct the examination according to the actual situation, and patients are advised to just follow the doctor’s instructions, whether holding their breath or not, for accurate results.