The electrocardiogram made by breath-holding is normal.
Under normal circumstances, when inhaling, the lung volume increases the negative pleural pressure increases, which can promote the return of peripheral blood into the atria; when exhaling, the lung volume decreases the negative pleural pressure decreases, which is conducive to cardiac ejection.
When holding your breath, the negative pleural pressure is at the same level, which reduces the effect on cardiac systole and diastole, and will have a certain effect on the heart rate, slowing down the heart rate. Breath-holding will also cause insufficient oxygen supply to the tissues of the body, and in order to increase blood and oxygen supply, the heart rate will reflexively increase.
However, whether the heart rate is accelerated or slowed down is within the range of normal heart rate, so the ECG results from breath holding are normal, but the results are inaccurate and do not truly reflect the heart’s condition.
The electrocardiogram done by holding the breath is normal but not accurate. If the electrocardiogram is done by holding the breath, the electrocardiogram should be rechecked in a quiet and stable state to clarify the real condition of the heart.