heart murmur

heart sounds

 

the sounds heard on the surface of the chest in the heart region; they are amplified by and heard more distinctly through a stethoscope. They are caused by the vibrations generated during the normal cardiac cycle and may be produced by muscular action, valvular actions, motion of the heart, or blood passing through the heart.

The first heart sound (S₁) is heard as a firm but dull “lubb” sound. It consists of four components: a low-frequency, indistinct vibration caused by ventricular contraction; a louder sound of higher frequency caused by closure of the mitral and tricuspid valves; a vibration caused by opening of the semilunar valves and early ejection of blood from the ventricles; and a low-pitched vibration produced by rapid ejection.

The second heart sound (S₂) is shorter and higher pitched than the first, is heard as a “dupp” and is produced by closure of the aortic and pulmonary valves.

The third heart sound (S₃) is very faint and is caused by blood rushing into the ventricles. It can be heard in most normal persons between the ages of 10 and 20 years.

The fourth heart sound (S₄) is rarely audible in a normal heart but can be demonstrated on graphic records. It is short and of low frequency and intensity, and is caused by atrial contraction. The vibrations arise from atrial muscle and from blood flow into, and distention of, the ventricles.

Abnormalities in Heart Sounds. Decreased compliance of a ventricle is characterized by a gallop or triple rhythm. Accentuation of the third heart sound (protodiastolic or ventricular gallop) is caused by the filling of a poorly compliant ventricle with blood under high venous pressure. A presystolic or atrial gallop is an accentuated fourth heart sound and is also caused by blood filling a poorly compliant ventricle. Merging of the third and fourth heart sounds is called a mesodiastolic or summation gallop. A very rare abnormality in which four heart sounds are heard distinctly is called a “locomotive” rhythm.

Heart Murmurs are sounds other than the normal heart sounds emanating from the heart region. They are often heard as blowing or hissing sounds as blood leaks back through diseased and malfunctioning valves or as blood is pushed through narrowed or stenotic valve orifices.

Precordial locations for cardiac palpation and auscultation of heart sounds. Closure of the mitral and tricuspid valves produces the S₁ heart sound; closure of the pulmonic and aortic (semilunar) valves produces the S₂ sound. From Polaski and Tatro, 1996.

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murmur

 [mer´mer]

an auscultatory sound, benign or pathologic, loud or soft, particularly a periodic sound of short duration of cardiac or vascular origin.

aortic murmur a sound indicative of disease of the aortic valve.

apex murmur (apical murmur) a heart murmur heard over the apex of the heart.

arterial murmur one in an artery, sometimes aneurysmal and sometimes constricted.

Austin Flint murmur a loud presystolic murmur at the apex heard when aortic regurgitation is preventing the mitral valve from closing; called also Flint's murmur.

blood murmur one due to an abnormal, commonly anemic, condition of the blood. Called also hemic murmur.

cardiac murmur heart murmur.

cardiopulmonary murmur one produced by the impact of the heart against the lung.

continuous murmur a humming heart murmur heard throughout systole and diastole.

crescendo murmur one marked by progressively increasing loudness that suddenly ceases.

Cruveilhier-Baumgarten murmur one heard at the abdominal wall over veins connecting the portal and caval systems.

diastolic murmur a heart murmur heard at diastole, due to mitral obstruction or to aortic or pulmonic regurgitation with forward flow across the atrioventricular valve; it has a rumbling quality.

Duroziez's murmur a double murmur during systole and diastole, palpated over the femoral or another large peripheral artery; due to aortic insufficiency.

ejection murmur a systolic murmur heard predominantly in midsystole, when ejection volume and velocity of blood flow are at their maximum; it is produced by ejection of blood into the pulmonary artery and aorta.

Flint's murmur Austin Flint murmur.

friction murmur friction rub.

functional murmur a heart murmur occurring in the absence of structural changes in the heart, usually due to high cardiac output states. Called also innocent murmur and physiologic murmur.

Gibson murmur a long rumbling sound occupying most of systole and diastole, usually localized in the second left interspace near the sternum, and usually indicative of patent ductus arteriosus. Called also machinery murmur.

Graham Steell murmur a high-pitched diastolic murmur due to pulmonic regurgitation in patients with pulmonary hypertension and mitral stenosis.

heart murmur see heart murmur.

hemic murmur blood murmur.

innocent murmur functional murmur.

machinery murmur Gibson murmur.

mitral murmur a heart murmur due to disease of the mitral valve; it can be either obstructive or regurgitant.

musical murmur one that has a periodic harmonic pattern; it may be either a heart murmur or a vascular murmur.

organic murmur one due to a lesion in the organ or organ system being examined, e.g., in the heart, in a blood vessel, or in lung tissue.

pansystolic murmur a regurgitant murmur heard throughout systole, due to blood flow between two chambers normally of very different pressures in systole; the most common causes are mitral regurgitation, tricuspid regurgitation, and ventricular septal defects.

physiologic murmur functional murmur.

prediastolic murmur one occurring just before and with diastole, due to aortic regurgitation or pulmonic regurgitation.

presystolic murmur one shortly before the onset of ventricular ejection, usually associated with a narrowed atrioventricular valve.

pulmonic murmur one due to disease of the pulmonary valve or artery.

regurgitant murmur a heart murmur due to a dilated valvular orifice with consequent valvular regurgitation.

seagull murmur a raucous murmur resembling the call of a seagull, frequently heard in aortic stenosis or mitral regurgitation.

Still's murmur a functional heart murmur of childhood, with a buzzing or vibratory tone heard in midsystole; it usually disappears by puberty.

systolic murmur a heart murmur heard at systole, usually due to mitral or tricuspid regurgitation or to aortic or pulmonary obstruction.

to-and-fro murmur a friction sound or murmur heard with both systole and diastole.

tricuspid murmur a heart murmur caused by disease of the tricuspid valve; it may be either obstructive or regurgitant.

vascular murmur one heard over a blood vessel.

vesicular murmur vesicular breath sounds.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

An auscultatory sound of cardiac or vascular origin, usually caused by an abnormal flow of blood in the heart due to structural defects of the valves or septum; murmurs may be benign or pathological

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

heart murmur

  See Murmur.

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

heart mur·mur

(hahrt mŭr'mŭr)

A colloquialism for cardiac murmur (q.v.).

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

heart murmur

A sound caused by turbulent blood flow or vibration of a heart valve that may or may not indicate abnormality. Many heart murmurs are innocent.

Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

Heart murmur

Sound during the heartbeat caused by a heart valve that does not close properly.

Mentioned in: Mitral Valve Prolapse

Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

heart mur·mur

(hahrt mŭr'mŭr)

A colloquialism for cardiac murmur (q.v.).

Medical Dictionary for the Dental Professions © Farlex 2012

Patient discussion about heart murmur

Q. What is a Heart Murmur? My friend told me that some people have a heart murmor and it is normal. Is that possible? What is a heart murmur?

A. A heart murmur is a sound that is created by inadequate blood flow through the heart and its large vessels, for example the aorta. Some are born with a heart murmur and further testing doesn't reveal any significant problem. This is called a physiological murmur.
http://www.5min.com/Video/What-is-Innocent-Heart-Murmur-5501

Q. How are Heart Murmurs Classified? What are the characteristics of different heart murmurs?

A. Heart murmurs are charachterized by their location, their strength, their timing, whether or not they radiate and so on. For example, this is a sound of a heart murmur compatible with a disease called aortic stenosis-
http://www.dundee.ac.uk/medther/Cardiology/audio/as.wav
Notice that the murmur begin with the heart sound and lasts all through the beat.

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