What is a normal heart rate? (Strong Exam)

A discussion of how to measure and interpret the heart rate, including a deep dive on the evidence behind why the normal rate is *not* 60-100, despite widespread belief to the contrary.

@0:00 Introduction
@0:40 Heart rate vs. pulse rate
@2:52 Measurement of the heart rate
@4:06 Normal range of heart rate
@12:00 Etiologies of tachycardia
@13:16 Etiologies of bradycardia
@13:45 Pitfalls and mistakes

References:

Mason JW, et al. Electrocardiographic reference ranges derived from 79,743 ambulatory subjects. J Electrocardiol. 2007; 40:228-34.

Hjalmarson A, et al. Influence of heart rate on mortality after acute myocardial infarction. Am J Cardiol. 1990;65:547-53.

Aladin A, et al. Relation of resting heart rate to risk for all-cause mortality by gender after considering exercise capacity (the Henry Ford exercise testing project). Am J Cardiol. 2014; 114:1701-6.

Spodick DH. Survey of selected cardiologists for an operational definition of normal sinus heart rate. Am J Cardiol. 1993; 72:487-8.

Bainton JH, Levy RL, Munly WC, et al. Criteria for the Classification and Diagnosis of Heart Disease, 1st Ed. New York Tuberculosis and Health Association; 1928.

DeGraff AC, De La Chapelle CE, Eggleston C, et al. Nomenclature and Criteria for Diagnosis of Diseases of the Heart, 4th Ed. New York Heart Association; 1946.

Kossmann CE. The normal electrocardiogram. Circulation. 1953;920-36.

Dolgin M. Normal sinus rhythm. Am J Cardiol. 1993; 71:496-7.

Spodick DH. Redefinition of normal sinus heart rate. Chest. 1993; 104:939-41.

#physicalexam

[StrongMed]

Thank you everyone for the warm response to this series! I know the original plan was to post these physical exam videos at a rate of 4/week. However, after looking at the analytics from the first week, and talking to other educational YouTubers, I'm going to slow down just a little.

[lucasplaining_yt]

it makes my HR go to the 90s when a new strong video shows up

[lucasgffonseca]

8 years as a physician and always learning something new with Dr. Strong. Amazing, we appreciate it all around the world!

[tommasotedesco]

You Sir are a fantastic doctor and teacher. These videos are pure gold for all medical doctors! I wish I had a teacher like you during my years at the university.
Congratulations and greetings from Italy!

[VikMTB]

Thank you so much, as a junior dr i always had a gestalt feeling when patients had hr in the 90s that it was abnormal but i leaned back on being taught the normal goes out to 100. I will definitely bring this up and monitor those higher hr patients more closely. Great video, ive watched your videos for years and this new series is amazing so far can't wait for more. Best wishes from Australia.

[Reza-bekn]

The teacher's teacher - thank you, Dr. Strong.

[n.e]

This is gazing outside of the box! I like how you are very realistic, I mean; even when a concept isn't widely conventional, No one can beat your evidences. Thank you Strong!

[drklnel]

Thank you Dr Strong for this incredibly helpful material. Clarification on when to be concerned about a specific heart rate will change my practice and hopefully benefit my patients.

[Wasp]

I'm a medical intern in Fiji. Love how these videos are clinical based.

I really appreciated how you approached the normal heart rate range in an unorthodox way, citing 50-90 bpm based on clinical evidence. It was a refreshing take! I would love to see a similar deep dive into blood pressure. I think it’s a quite interesting topic, especially considering how blood pressure values can be influenced by measurement techniques and how the range is interpreted differently according to the patient’s clinical presentation.

[ItsPossible-uv]

Oh... Man... Thank You So Much ...
Love & Blessings....

[sunving]

Thank you Dr Strong, it is great as always.

[didisaythankyou]

I'd love to see a video on blood pressure. PS you rock! (2nd year Australian medical student)

[JM-iged]

That was really helpful. I do have AFIB and take Flecainide for it - but also from Bradycardia dipping into mid forties pretty often. Partly prob due to Antenolol and have cut way back to 1/2 pill. I sometimes wonder why my Kardia device will show AFIB at regular rate, just irregular but my doc does not believe it is really afib unless it is along with high heart rate, which it often is for other afib events.

[pg]

Thanks for the videos! Why shouldn't the range vary by country or region? Is it solely due to data restrictions from other areas?

[dsrini]

One other common cause of sinus bradycardia (especially in adolescents and young adults) which I have seen in my clinical practice is protein-calorie malnutrition due to an eating disorder (e.g. anorexia nervosa, bulimia nervosa, orthorexia [an extreme form of athlete's heart as mentioned in the video] or others). It is not impossible to see heart rates dip into the upper 20s at least briefly for these patients, with sustained rates in the 30s. Just another systemic cause to think of when a patient has sinus bradycardia, and not a reason to break out the atropine (as atropine will not work to raise heart rate in these patients).