Cardiac output reaches a maximum of 26-28 weeks at 32%, osobennos increases during labor.

Increasing the ISO and NE important for women with cardiovascular disease system, especially if signs of circulatory failure.

NK1 - increasing the ISO and NE by 23%.

HN2 - increasing the ISO and NE by 12%

Critical period - 28-32 weeks (maximum increases CBV and maximum reaches NE). NE during pregnancy increases the expense of increasing stroke volume and heart rate.

When a multiple pregnancy increases NE increase the maximum to 20 weeks.

The greatest intensity of the heart is determined at birth, in the battles: stroke volume increases by 300-500 ml (ie 30% and more rules). Also the intensity of the left ventricle - 50% (to 26-28 weeks).

At the heart influenced by hormones: estrogen, cortisol, hormones thyroid. The load on the heart increases because

· Growth of total body weight,

· Displacement of the heart in a horizontal position

· Increased intraabdominal pressure

· More highstand difragmy.