what should be the heart rate of a normal person
Heart rate Many texts cite the normal resting adult human heart rate as ranging from 60–100 bpm.[1] Tachycardia is a fast heart rate, defined as above 100 bpm at rest.[2] Bradycardia is a slow heart rate, defined as below 60 bpm at rest. Several studies, as well as expert consensus indicates that the normal resting adult heart rate is probably closer to a range between 50 and 90 bpm.[3][4][5][6] During sleep a slow heartbeat with rates around 40–50 bpm is common and is considered normal. When the heart is not beating in a regular pattern, this is referred to as an arrhythmia. Abnormalities of heart rate sometimes indicate disease.[7]
Heart The heart pumps blood with a rhythm determined by a group of pacemaking cells in the sinoatrial node. These generate a current that causes contraction of the heart, traveling through the atrioventricular node and along the conduction system of the heart. The heart receives blood low in oxygen from the systemic circulation, which enters the right atrium from the superior and inferior venae cavae and passes to the right ventricle. From here it is pumped into the pulmonary circulation, through the lungs where it receives oxygen and gives off carbon dioxide. Oxygenated blood then returns to the left atrium, passes through the left ventricle and is pumped out through the aorta to the systemic circulationâˆ’where the oxygen is used and metabolized to carbon dioxide.[8] The heart beats at a resting rate close to 72 beats per minute.[9] Exercise temporarily increases the rate, but lowers resting heart rate in the long term, and is good for heart health.[10]
QT interval Definitions of normal QTc vary from being equal to or less than 0.40 s (≤400 ms),[9] 0.41s (≤410ms),[10] 0.42s (≤420ms)[11] or 0.44s (≤440ms).[12] For risk of sudden cardiac death, "borderline QTc" in males is 431–450 ms; and, in females, 451–470 ms. An "abnormal" QTc in males is a QTc above 450 ms; and, in females, above 470 ms.[13]
Pulse Pressure waves generated by the heart in systole move the arterial walls. Forward movement of blood occurs when the boundaries are pliable and compliant. These properties form enough to create a palpable pressure wave.