As a medical professional with expertise in cardiology, I can provide you with an explanation of what an abnormal sinus rhythm is. An abnormal sinus rhythm refers to variations from the normal heart rate or pattern of electrical impulses that regulate the heartbeat. The sinus node, which is the natural pacemaker of the heart, typically initiates electrical impulses that cause the heart to contract and pump blood. Under normal circumstances, this results in a heart rate of 60 to 100 beats per minute for adults at rest. However, when the sinus node does not function properly, it can cause the heart to beat too fast, too slow, or irregularly. This失常的窦性心律** can manifest in several ways: 1. Tachycardia: A heart rate that is faster than the normal range, which can feel like a rapid or pounding heartbeat. 2. Bradycardia: A heart rate that is slower than the normal range, which might cause the heart to feel like it's skipping beats or beating too slowly. 3. Fluttering: A sensation that the heart is vibrating or fluttering in the chest, which can be indicative of atrial flutter, a type of arrhythmia. 4. Silent Arrhythmias: Some arrhythmias do not cause noticeable symptoms and are only detected through medical examination or monitoring. It's important to note that not all abnormal sinus rhythms are harmful. Some may be benign and require no treatment, while others may require medical intervention to prevent complications. read more >>

It just means it's out of its normal rhythm. It may feel like your heart skipped a beat, added a beat, is "fluttering," or is beating too fast (which doctors call tachycardia) or too slow (called bradycardia). Or, you might not notice anything, since some arrhythmias are "silent."read more >>