What would happen if the length of absolute refractory period in cardiac muscle cells was same as it is for skeletal cells?

The absolute refractory period is the time during which a cardiac muscle cell cannot generate an action potential, no matter how strong the stimulus. Skeletal muscle cells have a much shorter absolute refractory period than cardiac muscle cells, which allows them to contract more rapidly.

If the length of the absolute refractory period in cardiac muscle cells increased to be the same as skeletal muscle cells, several things would happen. First, the heart rate would decrease significantly, as the cells would take longer to recover between contractions. The decreased heart rate would lead to a drop in the body's ability to deliver oxygen and nutrients to tissues and organs. This could cause fatigue, shortness of breath, and, eventually, organ failure.

Additionally, the longer refractory period would make the heart more susceptible to arrhythmias, which are abnormal heart rhythms. Arrhythmias can cause the heart to beat too fast, too slow, or irregularly, which can be life-threatening.

It is clear that an increase in the length of the absolute refractory period in cardiac muscle cells would have several serious consequences for the body. This is why the heart has evolved to have a longer refractory period than skeletal muscle, allowing it to contract at a relatively slow and steady rate with a low risk of arrhythmias.