Factors Affecting Heart Rate and Blood Pressure

Blood pressure is measured in two stages: systolic and diastolic. Systolic refers to the amount of pressure placed on the arterial walls when the heart contracts. Diastolic refers to the amount of pressure placed on the arterial walls when the heart releases. There are several factors that can cause blood pressure as well as heart rate to fluctuate or change, often leading to circulatory or organ complications.

Vasoconstricors

• This is a term used to describe elements or substances that cause the veins to contract. This includes caffeine contained in several soft drinks and coffee as well as certain medications. As the veins contract, heart rate may fluctuate and blood pressure tends to rise.

Vasodilators

• This is a term used to describe elements or substances that cause veins to dilate and widen. As they widen, blood flow slows causing a decrease in blood pressure. Causes include dehydration and diuretics, which rid the body of excess fluids through excretion.

Body Mass

• A person's body mass can have a significant effect on both their heart rate and blood pressure. Obesity is a primary cause of high blood pressure and increased heart rate because the heart must work harder to pump blood to larger portions of the body.

  Pregnancy has the opposite effect on the circulatory system. Typically when a woman becomes pregnant, her systolic and diastolic blood pressure decreases five to 15 points during the first 24 weeks of gestation. Blood pressure will usually raise again post childbirth.

Malfunction

• Often as people age, they experience a malfunction in communication between the brain and the heart. This can matriculate into a disease known as orthostatic hypotension. In a person without orthostatic hypotension, the heart compensates for blood pooled to the body's extremities--often caused an extended period of sitting or lying down--by increasing its beat rate. In a person with orthostatic hypotension, this compensation does not occur. The result is a drop in blood pressure.

Infection

• Severe infection, also known as septic shock, can cause life-threatening drops in blood pressure. This commonly occurs when bacterial infections originating in the lungs, urinary tract or abdomen leave the infection site and enter the bloodstream. Blood pressure drops significantly as these bacteria begin to produce toxins that directly affect the blood vessels.

Warning

• These are only a few of the factors that can cause fluctuations in blood pressure and heart rate. Speak with a doctor if you experience a sudden change in blood pressure accompanied by chest pain, dizziness or fainting. These can sometimes be precursors to serious complications, such as kidney failure, shock and cardiac arrest.