Hypertension is defined as a blood pressure higher than 140/90 mm Hg, measured multiple times in rest. When no obvious underlying cause can be found, it is called primary or essential hypertension. In secondary hypertension, there is an underlying endocrine (Cushing, pheochromocytoma), neuronal, or renal cause.
Hypertension as such will not give rise to symptoms. However, long-term increased blood pressure increases the workload of the heart, which requires increased left ventricular muscle mass. A hypertrophic heart, in turn, needs more oxygen. When the coronary arteries cannot keep up with the oxygen demand, ischaemia can result. Moreover, increased blood pressure also stresses arterial walls, which then develop arteriosclerosis more easily and can cause end-organ damage.
Long-term hypertension can lead to all the following EXCEPT
The most important component in vascular resistance is