Blood pressure is the force exerted by circulating blood against the walls of the body’s arteries. A reading is given as two numbers, measured in millimeters of mercury (mmHg). The first, or top, number is the systolic pressure, which measures the pressure when the heart beats. The second, or bottom, number is the diastolic pressure, which reflects the pressure when the heart rests between beats. A reading of 173 blood pressure refers specifically to the systolic measurement.
Defining High Blood Pressure Stages
A systolic reading of 173 mmHg is categorized as severely elevated and falls within Stage 2 Hypertension. Normal blood pressure is defined as a systolic reading below 120 mmHg and a diastolic reading below 80 mmHg. Readings where the systolic pressure ranges from 120 to 129 mmHg, with diastolic pressure below 80 mmHg, are classified as Elevated blood pressure.
Stage 1 Hypertension is defined by a systolic pressure between 130 and 139 mmHg or a diastolic pressure between 80 and 89 mmHg. Stage 2 Hypertension begins at a systolic pressure of 140 mmHg or higher or a diastolic pressure of 90 mmHg or higher. The 173 mmHg reading significantly exceeds the Stage 1 range, placing it firmly in the Stage 2 classification. This serious finding requires prompt medical attention.
This reading approaches the threshold for a Hypertensive Crisis, defined as a systolic pressure of 180 mmHg or higher or a diastolic pressure of 120 mmHg or higher. Although 173 mmHg is just below this threshold, it indicates dangerously high blood pressure. Immediate consultation with a healthcare professional is necessary to prevent potential health complications.
Risks Associated with Severely Elevated Readings
A sustained systolic pressure of 173 mmHg places damaging strain on the circulatory system and internal organs. This high pressure forces the heart muscle to work excessively hard against increased arterial resistance. This overworking can lead to thickening of the heart muscle, compromising its function and potentially contributing to heart failure.
The arteries become less elastic and their inner lining may develop damage from the constant, high-force blood flow. This damage allows fatty material to accumulate, accelerating atherosclerosis, which is the hardening and narrowing of the arteries. A major risk at this pressure level is a stroke, which occurs if a blood vessel in the brain ruptures or becomes blocked.
Severely elevated pressure can also affect delicate organs that rely on small blood vessels for their function. The kidneys, which filter waste from the blood, can suffer damage to their filtering units, potentially leading to a rapid decline in kidney function. The small vessels in the eyes are also vulnerable to damage, which can result in vision changes or loss.
This level of pressure increases the risk of an aortic dissection, a life-threatening condition where the inner layer of the main artery tears. The pressure can also lead to pulmonary edema, where fluid backs up into the lungs, causing shortness of breath. These acute complications warrant immediate medical evaluation.
Immediate Actions After Measuring 173 Systolic
If a home device measures a systolic reading of 173 mmHg, the first step is to remain calm and sit quietly for about five minutes. Anxiety or recent physical activity can temporarily spike blood pressure, so a period of rest is necessary. After this period, the blood pressure should be re-measured to confirm the reading’s accuracy.
If the second reading remains at 173 mmHg or higher, immediately contact a healthcare provider or medical advice line. Explain the confirmed reading and inquire whether a visit to an urgent care clinic or emergency department is appropriate. This level of high blood pressure is considered a medical urgency.
The most serious concern is the presence of symptoms indicating a true hypertensive emergency. If the 173 mmHg reading is accompanied by a severe headache, chest pain, shortness of breath, sudden weakness, numbness, or difficulty speaking, call emergency services immediately. These symptoms suggest possible organ damage and require rapid medical intervention.
If no such symptoms are present, the situation is classified as severe hypertension, or hypertensive urgency. This requires a prompt medical evaluation but not necessarily an emergency call. A healthcare professional may advise immediate adjustments to existing medication or prescribe new medication to safely lower the pressure over several hours. The distinction between urgency and emergency is based on the presence or absence of acute organ damage.
Medical Management Strategies
Once the immediate situation is stabilized, medical management involves a comprehensive, dual strategy. Physicians typically initiate antihypertensive medication to quickly and effectively bring the pressure down to a safer target range, often aiming for less than 130/80 mmHg. Initial treatment often combines two different classes of medication, such as a calcium channel blocker and a thiazide-like diuretic, to achieve rapid control.
Various drug classes are available, including Angiotensin-Converting Enzyme (ACE) inhibitors, Angiotensin II Receptor Blockers (ARBs), and beta-blockers. The specific choice depends on the patient’s health profile and existing conditions. Simultaneously, lifestyle modifications are required as a permanent part of the treatment plan. These changes support the treatment but are not a substitute for medication at this pressure level.
Lifestyle adjustments include adopting the Dietary Approaches to Stop Hypertension (DASH) diet, which emphasizes fruits, vegetables, and low-fat dairy while restricting sodium. Regular physical activity and weight management are important components to reduce physical stress and sustain lower blood pressure. Consistent home monitoring and regular follow-up with the healthcare team are necessary to ensure the regimen is effective and to make adjustments.