A low pulse rate and high blood pressure are not often present together. Generally, when one has a low pulse rate it is accompanied by a low blood pressure, and a high blood pressure is accompanied by a normal or higher than normal pulse. There are a few instances where a low pulse rate might be accompanied by a high blood pressure.
A low pulse rate of less than 60 beats per minute is referred to as bradycardia. A high pulse rate of more than 100 beats per minutes is called tachycardia. Normal blood pressure is defined as having a systolic pressure that ranges from 90 to 140 mmHg (millimetres of mercury), and a diastolic pressure that ranges from 60 to 90 mmHg. Blood pressure is read as the systolic pressure over the diastolic pressure.
A myocardial infarction, more commonly known as a heart attack, is one instance in which a patient could present with a low pulse rate and a high blood pressure. This is usually seen in a patient who already suffers from hypertension (high blood pressure) before the actual myocardial infarction takes place. Depending upon which coronary artery is affected, the patient may experience a low pulse but high blood pressure throughout the event.
Sick sinus syndrome occurs when there has been some type of damage done to the synoatrial node which regulates the electrical activity of the heart. With sick sinus syndrome, the heart may be either bradycardiac or tachycardiac, or may volley back and forth between the two. If an individual already suffers from hypertension when sick sinus syndrome begins, chances are the individual will present with a low pulse and high blood pressure.
Atrial fibrillation is often caused when there is a problem with the AV (atrial ventricular node), which regulates the contraction of the heart. Atrial fibrillation often causes the atrium to quiver before beats, which slows the heart rate down, or it can spasm, which causes the heart rate to increase. If a patient suffers from both hypertension and atrial fibrillation, the patient may have a high blood pressure and low pulse rate.
Certain medications, such as beta blockers that slow the heartbeat, can cause a patient to present with a low pulse rate and high blood pressure (even though most of these medications can also cause a decrease in blood pressure). If an individual has essential hypertension, a form of the condition in which no known cause can be identified, beta blockers will probably not decrease the blood pressure.