Heart rate 145 on an adult - what does it mean?

Where 145 bpm sits on the adult scale

What a resting pulse of 145 means

If you just climbed stairs, exercised or are very anxious, a pulse of 145 can be a normal response and should fall within minutes. A fast rate that persists at rest can come from fever, dehydration, blood loss or anemia, an overactive thyroid, or a heart rhythm disorder such as atrial fibrillation, atrial flutter or supraventricular tachycardia (SVT).

An irregular pulse at this speed is a typical sign of atrial fibrillation, which raises stroke risk and should always be evaluated.

Ranges apply to adults and children aged 10 and older, measured at rest (American Heart Association). By the numbers: at 145 bpm the heart beats about every 0.41 seconds — roughly 208,800 beats a day.

Arriving at the ER with a pulse of 145: how doctors decide to slow it

Within minutes of arriving with a fast heart, you will usually be connected to a monitor, have a 12-lead ECG taken, and have a small tube placed in a vein. The ECG answers the first big question: is this the normal pacemaker running fast, or an abnormal rhythm? Blood tests follow for blood count, salts, thyroid, infection markers and heart strain.

The answer decides whether the rate should be slowed at all. When the normal pacemaker is speeding up because of fever, blood loss, dehydration or pain, the fast rate is helping the body cope. Forcing it down with medicine could make things worse. Treatment then targets the cause: fluids, fever control, pain relief, oxygen or antibiotics. The pulse comes down on its own as the cause improves.

When the rhythm itself is the problem

For rhythms such as atrial fibrillation or atrial flutter with a fast rate, slowing the heart is a main goal. Two groups of medicines are common:

• Beta blockers block the effect of adrenaline on the heart. They slow the signal through the heart’s electrical junction box between the upper and lower chambers, so fewer beats get through. Some act within minutes when given into a vein.
• Calcium channel blockers of a specific type slow the same junction in a different way.

Doctors choose between them based on blood pressure, how well the heart pumps, and conditions such as asthma, which can make some beta blockers unsuitable. Staff watch blood pressure closely because both groups can lower it.

For a regular SVT, vagal maneuvers or a fast-acting medicine called adenosine are usually tried first. If someone is unstable, with very low blood pressure, chest pain or confusion, a controlled electric shock under sedation can reset the rhythm at once.

Going home on a rate-slowing medicine

Many people leave with a tablet to keep the rate down. Expect your resting pulse to be lower than before and your heart rate during exercise to rise less. Tiredness, cold hands and lightheadedness on standing are common at first. Do not stop a beta blocker suddenly, because the heart rate can rebound; talk to the prescriber if side effects bother you. Keep a log of morning readings for your follow-up visit.

None of this is a home treatment. A resting 145 that does not settle after rest needs a doctor today, and fainting, chest pain or severe breathlessness need 911. For lifestyle steps that help over time, see how to lower your heart rate.

For a reliable resting value, sit quietly for five minutes first and average a few mornings: Resting Heart Rate: What It Says About Your Health. You can also measure by tapping along on the start page.

Nearby values

• 140 bpm
• 141 bpm
• 142 bpm
• 143 bpm
• 144 bpm
• 146 bpm
• 147 bpm
• 148 bpm
• 149 bpm
• 150 bpm

Measured on a child instead? See heart rate 145 in a child.

Sources: American Heart Association: All About Heart Rate · MedlinePlus: Pulse · ACSM position stand on exercise intensity (2011)

This page explains a single reading in general terms. It is not a diagnosis. Heart rate alone cannot tell whether the rhythm is regular or whether the heart is healthy — if you are worried, talk to a doctor.