Normal Heart Sounds

Innocent Murmur | Auscultation #11 | Lesson with Audio

patient thorax when auscultating by stethoscope

The patient was supine during auscultation.

Description

This is an example of an innocent murmur. This type of murmur is seen with non-cardiac conditions such as pregnancy, hyperthyroidism, exercise and anemia. When these are treated appropriately, the systolic murmur disappears. The murmur is heard in early systole, is of short duration and has a frequency range of 120Hz to 250Hz. It is best auscultated in the pulmonic area and increases in intensity with inspiration. It can be heard with either the bell or diaphragm. In this example S1 and S2 are normal. Diastole is silent. The short duration and mid-range frequency characterize an innocent murmur.

Phonocardiogram

Anatomy

Innocent Murmur

Authors and Sources

Authors and Reviewers

Heart sounds by Dr. Jonathan Keroes, MD and David Lieberman, Developer, Virtual Cardiac Patient.
Lung sounds by Diane Wrigley, PA
Respiratory cases: William French
David Lieberman, Audio Engineering
Heart sounds mentorship by W. Proctor Harvey, MD
Special thanks for the medical mentorship of Dr. Raymond Murphy
Reviewed by Dr. Barbara Erickson, PhD, RN, CCRN.
Last Update: 11/10/2021

Sources

Heart and Lung Sounds Reference Library Diane S. Wrigley
Publisher: PESI
Impact Patient Care: Key Physical Assessment Strategies and the Underlying Pathophysiology
Diane S Wrigley & Rosale Lobo
Practical Clinical Skills: Lung Sounds
Essential Lung Sounds Diane S. Wrigley, PA-C
Published by MedEdu LLC
PESI Faculty - Diane S Wrigley
Case Profiles in Respiratory Care 3rd Ed, 2019
William A.French
Published by Delmar Cengage
Essential Lung Sounds by William A. French
Published by Cengage Learning, 2011
Understanding Lung Sounds Steven Lehrer, MD
Clinical Heart Disease W Proctor Harvey, MD
Clinical Heart Disease
Laennec Publishing; 1st edition (January 1, 2009)
Heart and Lung Sounds Reference Guide
PracticalClinicalSkills.com