ASSESSMENT PHOTO GUIDE

GET IN TOUCHAND IN TUNE WITH

CARDIACASSESSMENT

Part 2BY VICKIE A MIRACLE. RN. CCRN. MSN

Critical Care Specialist • Baptist Hospital East • Louisville. Kentucky

Last month's photo guide focused on normal heart sounds.This month, we'll show you how to detect

murmurs, clicks, and rubs.

THREE CAUSES OF MURMURS

A. High blood flow B. Stenotic valve C. Backflow ol blood

THE FOUR VALVE AREAS

Normal heart sounds arebest heard not over thevalves themselves, butover the valve areas ••••(indicated by the --—•—'

42 Nursing88, April

onathan Wilson, age 56. suf-fered an anterior myocardialinfarction (MI) 5 days ago.He has just been transferredto the medical/surgical unit,arriving toward the end ofthe

last nursing shift. According to report.Mr. Wilson is resting comfortably andhas no chest pain or dyspnea. His heartrate is 84 and regular; his blood pres-sure is 126/74 mm Hg.

Now it's time for a more completeassessment of Mr. Wilson's cardiac sta-tus. Because of his MI, the nurse com-ing on duty must be especially alert forabnormal heart sounds such as mur-murs.

Three causes of murmursTo understand murmurs, recall how theheart's valves work. Normally, theyopen to let blood through, then closeto prevent a backflow. The turbulenceof abnormal blood flow through a valveproduces the sound called a murmur.The three main causes of murmurs are(see Photograph 1):

A. high blood flow through a normalvalve, which may occur with fever, hy-perthyroidism. or pregnancy

B. blood flow through a stenotic (orconstricted) valve

C. backflow of blood through a ré-gurgitant (or insufficient) valve.

Palpating valve areasBefore you can auscultate for murmurs,you must perform the basic cardiac as-sessment described in last month's As-sessment Photo Guide. This meansinspecting and palpating the four valveareas and identifying the normal heartsounds, S, and S, (see Photograph 2).The nurse assessing Mr. Wilson wouldbegin by making sure he's lying on hisback, with the head of the bed raised30 to 45 degrees. This is a good po-sition for an MI patient because it easesthe work load on his heart.

When palpating the four valve areas,you can follow any sequence you like.But to ensure consistency, use the samesequence for palpation and ausculta-tion. We'll use a common sequence,starting at the mitral valve area andmoving on to the tricuspid, the aortic,and then the pulmonic valve areas.

The mitral valve area, you'll remem-ber, is also the point of maximal im-pulse (PMI). It should be I to 2 cm in

AUS!diatneter or roughly the size of aquarter. Using your palm, palpate thisarea for thrills—palpable murmurs thatindicate turbulent blood flow. If you'veever put your hand on a purring cat.you know just what a thrill feels like.Next, use your finger pads to palpatethe mitral valve area for pulsations,which feel similar to a bounding pulse.This finding may indicate increasedblood volume or pressure.

Now move on to the other three valveareas, palpating in the same manner.At each stop, use your palms to feelfor thrills, then use your finger pads tofeel for pulsations.

Auscultating murmursAfter palpation comes auscultation.First, listen at each of the four valveareas for the normal heart sounds, S,and S;. Then go back to the mitral valvearea atid auscultate for a murmur (seePhotograph 3). Use both the diaphragmand the bell of your stethoscope for atleast 30 seconds each, listening care-fully between S, and S, and between S,and S,.

If your patient has a murmur, you'llhear a distinctive rumbling sound dur-ing these normally quiet periods. De-tecting murmurs isn't difficult. Theyhave a unique sound; once you hearone. you'll remember it.

Keep this auscultation tip in mind:Place the diaphragm firmly against theskin; place the bell lightly against theskin so it doesn't act as another dia-phragm.

When you're done listening for mur-murs at the mitral valve area, go to thetricuspid. aortic, and pulmonic valveareas. If you do detect a murmur, you'llhave to assess it for eight specific char-acteristics. Learning to perform thissophisticated assessment won't happenovernight. It'll take good teachers andlots of practice.

Let's take a look at each of theseeight characteristics of a murmur.

1. LocationThe location of a murmur refers to thevalve area where it's best heard. Cer-tain murmurs are best heard in one ofthe four valve areas. The murmur ofaortic stenosis, for example, will beloudest at the aortic valve area.

2. PitchA murmur may be low. medium, orhigh pitched, depending on the velocityof blood flow. To evaluate a murmur's

HE MiTRAL VALVE AREA

pitch, listen with both the bell and thediaphragm. If you hear the murmurbest with the bell, it's low pitched. Ifyou hear it best when using the dia-phragm, the murmur is high pitched.And if you can hear the murmur justas well with the bell or the diaphragm,it's medium pitched.

3. TimingTiming refers to whether the murmuroccurs during systole or diastole. If youhear a murmur between S, and S ,̂ it'ssystolic. If you hear one between S,and S,. it's diastolic. Systolic murmursmay be benign; diastolic murmursnever are.

4. Place and durationIdentifying exactly where during sys-tole or diastole a murmur occurs (place)and how long it lasts (duration) can bedifficult. But with experience, you'lllearn to describe these features.

Systolic murmurs are'classified asfollows:• A pansystoUc or holosystolic murmurlasts for the entire systolic phase.• An early systolic or ejection murmurstarts right after S, and ends at mid-systole.• A midsystolic murmur starts after S,and ends before S;.• A ¡ate systolic murmur starts at mid-systole and ends at S^.

For diastolic murmurs, rememberthese classifications:• An early diastolic murmur starts withS; and ends at middiastole.• A middiastolic murmur starts afterS, and ends before S,.• A late diastolic or presystolic mur-mur starts at middiastole and ends at

s,.Murmurs that can be heard through-

out systole and diastole are known ascontinuous murmurs.

5. Loudness or intensityYou'll grade the loudness or intensityof the murmur on a six-point scale. Thegrades are written as a fraction using

Nursing88, April 43

AUSCULTATING FOR CHANGES IN A MURMUR

Murmurs may become louder or softer when the patient changes position, It you detect amurmur, have the patient sit up (Photograph 4) then lie on his left side {Photograph 5), soyou can auscultate for any changes in the murmur.

44 Nursing88, April

Roman numerals. The numerator in-dicates the loudness of the murmur; thedenominator is always VI. Here's thescale:I/VI: very faint, easily missedII/VI: barely audibleIII/VI: easily heardIV/VI: easily heard; may be accom-panied by a thrillV/VI: louder with a thrillVI/VI: very loud with a thrill; can beheard with stethoscope 1 inch abovechest wall.

If youYe just learning to listen tomurmurs, grading the intensity can beespecially challenging. But don't worry.This is an advanced skill that you'lldevelop with proper instruction andpractice.

6. QualityThe quality of a murmur consists of itscharacteristic pattern and sound. Whendetermining the quality, keep these fourpatterns in mind:• A crescendo murmur starts softly andbuilds in intensity. Its sound may bedescribed as coarse, rumbling, orwhooping.• A decrescendo murmur starts loudly,then becomes less intense. It may re-semble a blowing or whistling sound.• A crescendo-decrescendo murmurstarts softly, becomes louder, then soft-ens again. The sound may be describedas harsh, grating, or coarse.• A plateau murmur sounds the samethroughout its duration.

7. RadiationDetermine if the murmur radiates toother parts of the precordium or to theneck, back, shoulders, or left axilla.Usually, the higher the pitch and thegreater the intensity, the more likely amurmur will radiate. Knowing whereit radiates helps you identify the mur-mur. For instance, the murmur causedby mitral insufficiency frequently ra-diates from the mitral valve area to theleft axilla.

8. ChangesSome murmurs will be affected bychanges in respiration or position. Askyour patient to hold his breath, thenauscultate to see if the murmur getslouder or softer. You may also ask himto change position—perhaps to sit upor lie on his left side—so you can listenfor any changes in the murmur (seePhotographs 4 and 5).

A GUIDE

Condition Location

mitral mitral areaInsufficiency

tricuspid tricuspidinsufficiency area

aortic aortic areastenosis

Idiopathic aortic area.hypertrophie 3 RICS,subaortic 4 RICSstenosis

pulmonic puimonicstenosis area

mJtrai mitral areastenosis

tricuspid tricuspidstenosis area

aortic aortic area.insufficiency 3 LICS

4 LICS _^

pulmonic putmonicinsufficiency area

TO CONDITIONS THAT COMMONLY PRODUCE HEART MURMURS

Pitch

high

place andTiming duration Intensity Quality Radiation

systolic pansystolic/ I-VA/Iejection, ifmild, tätesystolic

medium systolic pansystolic/ 1-VA/lelection

medium systolic midsystolic varies

high systolic ejection varies

plateau to left axilla

plateau to rightsterna!border

crescendo- to neck,decrescendo upper back,

right carotid.apex

crescendo- to neck,decrescendo upper back,

apex

medium systoiic midsystohc ill-IV/VI crescendo to left side

low

high

high

1high

Dependitig on the patient's eondi-tion. some examiners will ask the pa-tient to squat. But you wouldn't havea patient like Mr. Wilson squat becauseof his recent MI.

Interpreting your findingsAfter you've assessed these eight char-acteristics, you'll be able to identifythe condition that's producing themur (see chart). Here are the twocategories of murmurs and somemon causes of each:

mur-maincom-

• benign—Many murmurs are classi-fied as benign, innocent, physiologic.or functional. These terms simply mean

diastolic middiastoiic/ I-IIA/Ipresystolic

diastolic early variesdiastolic

diastolic early I-VWÎdiastolic

diastolic early variesdiastolic

that the murmur isn't the result of anycardiovascular pathology. Frequently.benign murmurs will be heard in chil-dren, adults over 50. and pregnantwomen.• abnormal—Some systolic murmursand all diastolic murmurs are abnormalor pathologic. The more common ab-normal systolic murmurs result fromaortic and pulmonic stenosis. Diastolicmurmurs are produced by mitral andtricuspid stenosis as well as by aorticand pulmonic insufficiency.

Analyzing Mr. Wilson's murmurLet's get back to Mr. Wilson, who hadthat anterior MI several days ago. Dur-ing her cardiac assessment. Mr. Wil-son's nurse detects a murmur that's bestheard at the mitral valve area (loca-tion). She describes the pitch as high

of neck

crescendo none

decrescendo to apex,xiphoid

decrescendo to apex, leftsternalborder

decrescendo to apex

Changes

t withsquatting

iT with

respiration

î with sitting.supineposition.squatting,holdingbreath

î withinspiration,Val sal vamaneuver

t withinspiration

î in leftlateralposition, withexercise

î withinspiration

î withleaningfonward.exhalation

î withinspiration

because she hears the murmur best withthe diaphragm. The timing is systolic.and after listening carefully, she de-termines that the murmur is pansystolic(place and duration).

Mr. Wilson's murmur is loud.his nurse can palpate a thrill atmitral valve area, so she gradesintensity as V/VI. The sound is

andthethe

con-sistent throughout systole, which meansit's a plateau murmur (quality}.nurse also hears the murmur atWilson's left axilla (radiation}.cause of his condition, she doesn'thim squat. If she did. though, his r

TheMr.Be-

lavenur-

mur would become louder (changes).These assessment findings suggest to

the nurse that Mr. Wilson has mitral

Nursing88, April 45

CAUSE OF A CLICK

closes and the aortic valve opens soblood can be pumped from the lef(ventricle into arterial circulation

prolapse, the mttral valve doesn t close in«ystole because its posterior leaflet slipsback into the left ainum The result is aclick, usually heard in midsystole.

Illustration 1

CAUSE OF A RUB

46 Nursing88, April

insufficiency. In a patient like Mr. Wil-son, who has had an anterior Ml. mitralrégurgitation may indicate papillarymuscle dysfunction. His nurse reportsher findings and documents them asfollows: High-pitched, plateau, VlVI.pansystolic murmur heard in mitralarea. Sound radiates to left axilla.

Three types of clicksNext, we'll look at another patient,Pamela Wood, age 24. She's been ex-periencing dyspnea on exertion andpalpitations. A nurse is about to assessher cardiac status. But before we watchthat assessment take place, we need toreview how clicks differ from mur-murs.

For one thing, murmurs are sustained.Clicks aren't: They're short, high-pitchedsounds best heard wííh the diaphragm ofyour stethoscope. Clicks can occur dur-ing systole or diastole.

There are three types of clicks. Oneis simply called a click: it occurs duringsystole and is usually caused by mitralvalve prolapse (MVP). In patients withMVP, the posterior leaflet ofthe mitralvalve slips back into the left atrium insystole, causing mitral insufficiency(see Illustration I). The click usuallyoccurs in midsystole. as the valve startsto snap back into the left atrium. Tohear it, auscultate at the mitral valvearea, using the diaphragm. You mayalso hear the click at the tricuspid valvearea.

The second type of click is called anejection sound. It's caused by the ejec-tion of blood from the right ventriclethrough a defective pulmonic valve orfrom the left ventricle through a de-fective aortic valve. Again, the soundis short and high pitched. Best heardwith the diaphragm, an ejection soundoccurs in early systole, just after S,.

Aortic ejection sounds are best heardat the mitral valve area and may radiateto the aortic valve area. Respirations

don't affect these sounds, which mayresult from aortic stenosis or aortic re-gurgitation.

You'll hear pulmonic ejection soundsbest at the pulmonic valve area; theymay radiate to the xiphoid process. Thesounds will decrease with inspirationand increase with expiration. Possiblecauses include pulmonic stenosis, pul-monary hypertension, and pulmonaryembolism.

The onty diastolic click is called anopening snap, which results from theopening of a stenotic mitral valve. Likethe other clicks, it's short and highpitched. You'll hear an opening snapduring early diastole, right after S,. It'sbest heard when you place the dia-phragm between the tricuspid valvearea and the mitral valve area. Thesound won't radiale and isn't affectedby respirations.

Now, we're ready for the assessmentof Ms. Wood, who is experiencing dys-pnea on exertion and palpitations. Fol-lowing inspection, palpation, andauscultation of S, and S¡. her nurselistens for abnormal sounds. Whileauscultating with the diaphragm at themitral valve area, she hears a click.The sound is short and high pitched.Listening more closely, she notes thatthe click occurs at midsystole. GivenMs. Wood's symptoms and this finding,the nurse suspects that Ms. Wood hasMVP. The nurse charts her findings asfollows: A high-pitched click heard atmidsystole at the mitral valve area.

Pericardial friction rubsFinally, let's look in on Harry Bullock,age 68, who had an anterior MI a cou-ple of days ago. He's receiving a li-docaine (lignocaine) drip at 2 mg/minute for occasional premature ven-tricular contractions, but his conditionhas been stable since the MI. Mr. Bull-ock complains of discomfort in the an-terior left chest, which worsens whenhe breathes deeply. His nurse suspectspericarditis, so she'll auscultate for apericardia! friction rub.

Like murmurs, pericardial frictionrubs are sustained sounds. And likeclicks, friction rubs are high pitched.The difference is in the nature of the

sound itself. Friction rubs are often de-scribed as coarse or scratchy. To get anidea of what they sound like, try this:Hold the diaphragm of your stetho-scope against your left palm, then rubyour right thumb over the first and sec-ond knuckles of your left hand. Thesound you'll hear is similar to a frictionrub.

What causes friction rubs? Nor-mally, the movement of the parietal andvisceral sacs is smooth and silent. Butconditions such as infection, uremia,or MI can cause pericarditis. This con-dition produces a scratchy sound as theparietal and visceral surfaces rubagainst each other (see Illustration 2).Typical signs and symptoms of peri-carditis can include precordial chestdiscomfort, shortness of breath, fever,chills, and weakness.

Listen for a pericardial friction rubwith the diaphragm of your stetho-scope. You may hear the sound any-where along the anterior left chest, butyou'll probably hear it best at the tri-cuspid valve area. It may help to havethe patient lean forward and exhaleforcefully. After he's exhaled, listen forthe friction rub. That way. you can hearthe rub without any interference fromthe sounds of expiration. You shouldbe able to hear the sound during bothsystole and diastole. Keep in mind,though, that friction rubs can be in-termittent.

Mr. Bullock's nurse asks him to leanforward. Then she auscultates at thetricuspid valve area. There, she hearsa scratchy sound that gets louder afterMr. Bullock exhales forcefully. In hernurses' notes, she writes: Pericardialfriction rub heard at tricuspid valvearea.

Assessment tip:Before you auscultate

for a rub, have thepatient lean forward

and exhale forcefully.

Learning to listenRecognizing abnormal heart soundswon't come as easily as recognizing thenormal ones. Learning to detect thedifferent kinds of murmurs, clicks, andrubs means honing your listening skillsover time. Be patient, but persistent.

Practice on patients with normalheart sounds and on those with abnor-mal sounds. But don't spend a lot oftime with a very sick patient. You don'twant to wear him out while you try toidentify an abnormal sound. Instead,get an experienced nurse or doctor tolisten. Then try to hear what the moreexperienced practitioner hears.

Go on rounds with cardiac nurse cli-nicians and doctors, and ask to listento every abnormal sound they hear. Askthem to describe the various charac-teristics ofthe sounds—location, loud-ness, and the like.

As with any assessment skill, themore you practice, the better you'll get.So keep at it. In time, you'll be able toidentify murmurs, clicks, and rubs withconfidence. Hi

SELECTED REFERENCESBecker. K . and Stevens. S ; "Get in Touch andin Tune with Cardiac Asse>smenl. Part 1."Nursing88 18:51. March 1988

Erickson, B.: "Detecting Abnormal HeartSounás," Nursing86. 16:58. January 1986

Miracle. V.: "Anatomy of a Murmur."/Viir.iin;?So.16:26. July 1986.Saul. L.: "Heart Sounds and Common Murmurs."American Journal of Nursing. 83:1680. December1983.

Stern. E. Rapid Interpreiatwn of Heart Sounds.2nd edition. Philadelphia. Lea and Febiger. 1985

Taylor. D. : "Assessing Heart Sounds." Nursing 85.15:51. Januarv 1985

Nursing88, April 47