There are three number that you get when you take your blood pressure the top, largest number, systolic pressure. This measure the pressure during contraction. Contraction is controlled by the mineral calcium.
The second number is lower and measures the diastolic pressure during relaxation. This is controlled by the mineral magnesium, it takes more energy to relax the heart than contract it.
The bottom number is the pulse rate, the number of times per minute that the heart beats. This is controlled by the mineral potassium. If potassium is low the pulse rate goes up, if is potassium high pulse rate goes down.
Hair tissue mineral analysis looks at these minerals and ratios. For example potassium is part of the sodium / potassium ratio, which also affects the adrenal glands.
The magnesium ratio is part of the calcium / magnesium ratio which affects the thyroid gland.