High blood pressure (hypertension)

High blood pressure (hypertension) results from increased resistance to flow.
  This may be because vessels are narrowed or because the blood is more viscous than normal.
  Increased cardiac output does not cause sustained hypertension, but can produce a transient rise.
  Emotional stresses of all kinds are reflected in the blood pressure.
  Excitement, agitation or annoyance stimulates sympathetic nervous activity, which accelerates the heart and contracts arteriolar muscle, both of which effects cause hypertension.
  A heated argument can raise blood pressure to as much as 240 mm (systolic)/130 mm (diastolic) - normal values are 120/80.