Cardiac: Cases and Answers

• Transposition of Great Vessels
• Tetrology of Fallot
• Total Anomolous Pulmonary Venous Return
• Tricuspid Atresia
• Truncus Arteriosus
• Pulmonary Atresia

Case #2:  A Four year old girl comes in for a schedule well child visit has been remarkably well since the last visit.  She is growing well and has normal vital signs.  On exam there is a murmur that is heard near the LUSB, perhaps more laterally.  It does not vary during the cardiac cycle but goes away when she lies down.  It also changed when she looked at her mother to one side.  When you look over to her mother you note that she is very nervous.  “My grandfather had a murmur and died… does my daughter have a murmur?”

This story and exam is consistent with one of the typical innocent murmur – a venous hum.  Venous hum is turbulent flow appreciated in the cervical veins and is appreciated most in the infraclavicular area.  It varies with position being loudest in an upright position and decreasing in supine position.  It will also vanish when the head is turned collapsing the veins and thus decreasing the turbulence.  The murmur is a continuous murmur and does not change with systole or diastole.

This is one of a number of innocent murmurs (Biancello) which will be found in nearly 70% of children.  Still’s murmurs, peripheral pulmonic stenosis, pulmonary flow murmurs (systolic and newborn), and carotid hums can be found in many patients and it is the primary care doctor’s job to make the diagnosis, allay the fears of the parent, and reassure the patient.  Innocent murmurs can be distinguished by their lack of features such as:  diastolic timing, harsh quality, holosystolic (incorporating S1), and most importantly other symptoms.

Her fears are based on an association murmurs and significant cardiac disease.  This is true that most people with significant cardiac disease do have turbulent flow and thus murmurs.  But the converse is not true.  Not all with murmurs have significant disease.  In fact the majority of patients with murmurs are transient innocent murmurs.  You can use pictures, close follow-up and information to appease the parents’ fears.  Make sure you ask why they are scared.  Many times there was a sick family member.

Taking a history and a careful assessment of the vital signs will help direct our exam.

• History- pallor, tachypnea, poor feeding, FTT, central cyanosis, chest asymmetry, genetic disorders, clubbing, exercise intolerance...
• Vitals – 4 extremities (a rare cause of a murmur is a coarct – typically heard in the back)

Observation – Syndromic features, cyanosis, pallor, body positioning.

Palpation- This should be done PRIOR TO AUSCULTATION

Pulses -          

• Weak = shock, CHF…
• Bounding/ “water-hammer” – aortic runoff lesions PDA or AI
• Pulsus Bigeminus – PVC’s
• Pulsus Paradoxus – Inspiratory fall of systolic pressure > 10mmHg – This represents and exaggeration of the normal decrease in systole in inspiration b/c of decreased LV filling. Causes: Tamponade, severe asthma, pericarditis
• Pulsus Alternans – LV dysfxn (a change in intensity of beats –strong then weak pulse)
• Pulsus Parvus et Tardus – AS
• Bisferiens – IHSS (also can see reverse pulsus paradoxus – insp. Incr. In sys BP)

Other palpable things-

• PMI – Near L sternal border in neonates – should progress L ward to midclav. Line
• Feel for heaves, can use a tongue blade to accentuate by placing under hand with tip on PMI and observe other end
• Thrills

Auscultation
-“The art of auscultation”- In Peds in Review Dr. Menashe uses the term ‘Hyposkillia” which is the loss of ability of clinicians to effectively examine hearts on their own without a confirmational echocardiogram.  Let’s see if we can try to remediate this…

The Stethoscope- A stethoscope is NOT an amplifier.  It is a filter and if used correctly, with the most important filter (your brain), you can isolate murmurs better.  Below is described how the parts of the stethoscope work together-

• Diaphragm- Dampen low frequency sounds – the tighter the diaphragm the higher its resonating frequency and the more lower frequency noise is attenuated. SO PUSH
• Bell- Filters low frequency sounds with a large, shallow depth being optimal, Light pressure, the skin is the diaphragm.  Many cardiologists prefer listing with the bell.
• Tubing – Long tubes dampen high frequency sounds – 10”-18” optimal and thick tubing to insulate from external sounds.
• Ear pieces to block out external noise

Selective listening – any instrument in the orchestra can be appreciated if you know how to listen for it.  So when the stethoscope touches the chest THINK about hearing something and PUSH.

S1 = atrioventricular valves                                                    S2 = Semilunar Valves

S1 is composed of M1 at apex and LLSB  plus  T1 at LLSB. 

Typically M1>T1 and normally about 30 ms apart.

S2 is composed of A2 and P2.  Typically A2 (2nd R interspace) > P2 (2nd L interspace).  P2 not usually heard at the apex but at the 4th – 5th interspace.  Therefore the physiologic split is best heard near the pulmonic area. A2 then P2. Split occurs mostly because of delay of P2.

• A2 increases with increased systemic pressure
• P2 with pulmonary hypertension also can spread to apex… also may be increased in ASD or VSD.
• Fixed split = ASD (in most cases) – a split will persist in supine but should be eliminated in seated position.

There are three phases to filling:

1. Ventricular pressure < Atrial leading to opening of AV valve.  This is the rapid filling phase accounting for 80% of filling à S3 comes from here
2. Diastasis (gap) 5% of filling – more passive filling
3. Atrial kick – 15% causes S4 (see below)

S3 – rapid filling of the ventricle in early to middiastole… heard best at expiration with bell at apex in L lateral decubitus.  Typically normal but can also be a sign of pathology as in a knock with pericarditis. S3 can be made louder by increasing venous return (supine w/ legs lifted).

S4 – filling following L atrial contraction (late diastole) = abnormal

Typically S4- S1----- S2.  Best with bell – with patient in L lateral decubitus position - volume increased by gripping L hand, thus increasing LV resistance.

With short diastoles or long PR intervals S3 and S4 form a singular summation sound

Sidebar- I have heard both that S3’s are pathologic and/or S4’s are pathologic throughout med school and residency – In general, I think S3’s are “more” normal in infancy and early childhood and S4 are “less” consistent with pathology in adulthood/adolescence.  Here is a quote from a cardiology text…

“Children and young adults often have a normal (physiological) S3 but do not have a normal S4. A normal S3 sometimes persists beyond age 40 years, especially in women]. After that age, however, especially in men, S3 is likely to be abnormal.  An S4 is sometimes heard in healthy older adults without clinical evidence of heart disease, particularly after exercise.” (Braunwald: Heart Disease 6th edition –2001;pg 63)

Also opening snaps and clicks…

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Heart Murmurs 

Cause of murmurs = TURBULENT FLOW

Anywhere from 50-90% (I saw one article say 100%) of kids will have a murmur detected.  The key is to discern the functional/innocent from the pathologic.

Description of murmurs

• Timing
• Intensity
• Location
• Duration
• Quality
• Radiation

1) Timing/Duration – Holosystolic or Pansystolic – MR, TR, VSD

Please note: I have also heard that these terms are used interchangeably by CHONY cardiologists and this is stated in Bates. A systolic murmur beginning with the first heart sound that extends through systole.  If you see the term pan- or holosystolic murmur on a test- it is pathologic.

SEM (systolic ejection murmur) – Does NOT include S1– usually decrescendo in nature

2) Intensity –  I-VI/VI

• I-III degrees of audibility ( I have heard that some say I/VI is quieter than S1S2, II/VI is equal and III/VI is louder)
• IV palpable thrill
• V stethoscope lifted off chest wall
• VI w/o stethoscope (mechanical valve)

3) Location/Radiation – A key for differential.  The left sternal border is divided and to simply say there is a LSB murmur should be reconsidered.

• Left UPPER SB – PS, ASD, Innocent pulm flow, PAS, AS, TOF, Coarct, PDA w/ Pulm HTN, TAPVR, PAPVR
• Right UPPER SB – AS, Subvalv AS, Supravalv AS
• Left LOWER SB – VSD, Still’s, HCM (or IHSS), TR, TOF
• Apical – MR, Mitral Valve prolapse, AS, HCM, Innocent murmur

4) Quality – Low/ medium/ High… Harsh… blowing.. musical

A neat trick: Put the stethoscope in your closed fist with the diaphragm facing your palm.  With the fleshy part of your index finger of your opposite hand softly stroke the area between your 1st and 2nd MCP’s (index and thumb)…. Now, use the fingernail and do the same.  The first is close to the sound of an innocent blowing murmur, the second, harsh like a VSD.

Examination Pearls:

Systolic murmurs – one can use positional changes or Valsalva maneuvers or breath holding to isolate etiologies. 

Most systolic murmurs get louder when the patient is supine.  (Venous hums and IHSS are exceptions)

• Quiet Inspiration or Sustained Abdominal Pressure – Increase venous return.  THIS AMPLIFIES R SIDED MURMURS – PS or TR
  
  
• Increasing Systemic Arterial Resistance (SAR) – Augment L sided regurgitant murmurs MR or VSD’s get louder. Squeezing hands is one method to do this.
  
  
• Standing to Squatting or leg elevation (passive) -  Increases both venous return and SAR. This increases BP, SV, and LV end diastolic volume.  Thereby DECREASING IHSS or MVP
• Note: With squatting the change in the murmur is rapid but with leg elevation occurs 15-20sec after 45 degrees is attained.
  
  
• Valsalva- Decreases venous return to Right heart and thus LVEDV and arterial BP fall. Increases systemic resistance. Decreases Aortic Stenosis but increases IHSS and MVP

Common innocent Murmurs-

• Basal Flow murmur – Pulmonic or aortic – most common – I to II/VI – heard at LUSM or RUSB  Differential ASD,PS, AS
• Still’s – Can be quite loud- 2yr-8yrs typically – low-pitched systolic murmur musical “like a twanging string” –louder when supine and heard in the LLSBàapex … caused by turbulent flow over false tendons (?) —R/O VSD, IHSS
• PPS – axillae/back > front- midsystolic ejection – if persists past 6-9 months question if this is ASD or branch artery stenosis.  Last longer in preemies
• Venous hum – 2-5 yrs – continuous murmur with no relationship to cardiac cycle… R or L infraclavicular area with radiation upward… turbulence in jugular vein and superficial neck veins… Loud when sitting but disappears when supine or turns neck. R/O PDA

Case #3-
A 16 yr athletic male comes in for a preparticipation physical.  He says “he just needs the form so he can play basketball”. 

To assess readiness to participate in athletics seems simple as most of the patients you will see are in excellent shape.  But you must rule out the potential for serious sequelae.  The most common type of sudden death in athletes in the US is cardiac and secondary to hypertrophic cardiomyopathy (HCM).  This is a difficult diagnosis to make but a few clinical questions can draw attention to potentially dangerous situations. 

• First, family history of early cardiac death.  Many types of HCM have autosomal dominant inheritance patterns.
• Syncopal episodes
• Chest pain or palpatations with exertion

On physical exam it is very important to look for changes in vital signs such as widened or narrowed pulse pressure or tachycardia.  Also look for other findings consistent with a syndrome such as Marfan’s or collagen vascular disease.

An important document is 2007 Guideline for Cardiac Preparticipation see Guideline.gov link here

There is still debate about this issue as there are some significant findings that can be discovered with CXR and EKG.  However Yi, et al found that it was more cost-effective to simply refer to a pediatric cardiologist rather than begin the investigation.  Reasons cited were errors in interpretation by the pediatricians and lack of sensitivity of the tests.