Title What is baseballâs âmodern eraâ? The start of the 20th century might not seem particularly modernâafter all, there were only 45 states in the Union, hardly anyone owned a car (the Model T didnât debut until 1908) and William McKinley, a Civil War vet, occupied the White House.
Sinus tachycardia is a normal increase in the heart rate. How it happens. The sinoatrial (SA) node --- the heart's natural pacemaker-sends out electrical signals faster than usual. The heart rate is fast, but the heart beats properly.inus tachycardia is a normal increase in the heart rate. How it happens. The sinoatrial (SA) node --- the heart's natural pacemaker-sends out electrical signals faster than usual. The heart rate is fast, but the heart beats properly.
1 Ischemia, or lack of blood flow, may also cause an abnormal EKG. 2  Heart rate abnormalities. 3  A typical human heart rate is between 60 and 100 beats per minute. 4  An EKG can determine if the heart is beating too fast or too slow. Ischemia, or lack of blood flow, may also cause an abnormal EKG. 2  Heart rate abnormalities. 3  A typical human heart rate is between 60 and 100 beats per minute. 4  An EKG can determine if the heart is beating too fast or too slow.