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Lab/ECG/Xray Rounds
The EM Resident Provisionally Known as
Sean Caine
CCFP-EM
March 5, 2008
Case
29 yo male presents with severe
lightheadedness and palpitations during
sexual activity
Symptoms persisted x 10-15 min
Spontaneous resolution
Case continued
Additional hx:
2 prev visits to ED in past month for similar symptoms
1st episode
Lightheaded while mowing the lawn
D/C home from ED after ECG and normal labs
2nd episode
Syncopal watching TV
Admitted for observation
Had serial cardiac enzymes and cardiac monitoring
Discharged home after negative work up
Instructed to f/u with GP
Case
Normal vitals and physical exam
ECG is obtained….
Hypertrophic Cardiomyopathy
(HCM)
Objectives

Background

Etiology

Pathophysiology

Clinical Presentation

ECG Findings

Treatment
Thank you…
Adam Davidson and Jeff Booker
Background

aka Idiopathic hypertrophic subaortic stenosis,
obstructive cardiomyopathy

Notable cause of sudden cardiac death among
athletes
 Accounting for 2-36% SCD among athletes

Prevalence of 0.1-0.2% of general population

Accounts for up to 60% of unexplained LVH

MOST COMMON genetic cardiovascular disorder
Background

SCD most common for those <35 yrs of
age1
– No age is immune from SCD

Annual mortality rates as high as 3-6%3
Etiology

30-50% due to familial inheritance1,5

Autosomal dominant inheritance with
variable penetration

mutations of 1 of 11 possible genes
encoding proteins for myocardial
sarcomere
15%
15%
35%
Pathophysiology

Hypertrophied, nondilated left ventricle in
the absence of another cause

Histology:
– Hypertrophied muscle cells
– Cellular disorganization in “whorled pattern”
– Abnormal fibrous tissue
– Scarring mimics healed MI
Schematic

Asymmetric septal
hypertrophy (ASH)

Systolic motion of MV
anteriorleaflet (SAM)

LVOT gradient

Mitral regurgitation
(MR)
2 Chamber Echo
Systole
Diastole
Morphologic Variants of HCM
Clinical Presentation

Can be completely asymptomatic

Presenting Symptoms
– Dyspnea
– Exercise intolerance
– Dizziness
– Chest pain
– Presyncope/syncope
– Sudden Cardiac Death
Clinical Presentation

Average age at diagnosis is 30-40 yrs

2% diagnosed before the age of 5

7% before the age of 10
Key features on history
Previous hx of syncope
Family history of SCD or early onset of
symptoms
Physical Examination

S4 gallop

Harsh crescendo-decrescendo midsystolic
murmur loudest at apex
– LOUDER with valsalva and standing
– SOFTENS with lying, squatting, or isometric exercise

Bifid arterial pulse,double/triple apical
impulse,palpable atrial gallop
THE ECG

Abnormal in 90%
ECG Findings
 LVH: 30%
– and associated ST and T wave changes

Deep NARROW Q waves (typically I, aVL, V5,
V6)

Left atrial enlargement: 25-50%
30 yo male with 20 min of lightheadedness
running to bus
31 yo female syncope preceded by
palpitations during physical activity
?????
?????
Diagnosis

Ultimately made by doppler Echo
Complications

Increased incidence of WPW

Chronic or paroxysmal afib (10-40%)

Moderate risk for infective endocarditis

SCD
Pharmacotherapy

β blockers are first line
– Verapamil or disopyramide prescribed with caution
when β blocker poorly tolerated

Afterload reducing agents with systolic
dysfunction/CHF
– ACEI, diuretics, digoxin

Amiodarone should be used for ventricular
dysrhythmias

Avoid nitrates (decrease preload and LVOT)
Nonpharmacologic therapy

Septal myomectomy

Alcohol septal ablation

ICD
Take Home Points

Be suspicious of unexplained LVH on ECG
– Especially in symptomatic patients

Think HCM with narrow qwaves in lateral
leads
References
1.
2.
3.
4.
5.
Ramaraj R. Hypertrophic Cardiomyopathy: Etiology, Diagnosis, Treatment. Cardiology in
Review. 2008; 14(4): 172-179.
Dovgalyuk J, Holstege C, Mattu A, Brady WJ. The electrocardiogram in the patient with
syncope. American Journal of Emergency Medicine. 2007; 25: 688-701.
Kelly BS, Mattu A, Brady WJ. Hypertrophic cardiomyopathy: electrocardiographic
manifestations and other important considerations for the emergency physician. American
Journal of Emergency Medicine. 2007; 25:72-79.
Jouriles NJ. Hypertrophic Cardiomyopathy. Marx: Rosen’s Emergency Medicine: Concepts and
Clinical Practice. 6th ed. 2006.
Niemann JT. Hypertrophic Cardiomyopathy. Emergency Medicine: A comprehensive study
guide. 6th ed. 2004: 379-380.
Sudden Cardiac Death

Risk factors







Sustained VT
Recurrent syncope (esp w/exertion)
Family hx of 1 or more SCD
Extreme LVH (>30mm wall thickness)
LVOT gradient >30mmHg
Abnormal BP response to exercise
Nonsustained VT ambulatory monitor
0-1 RF = 1% annual SCD rate
 2 or more= increased risk of SCD and
prophylactic ICD should be considered

Distinguishing hypertrophic cardiomyopathy (HCM) from "Athlete's Heart"
Parameter
Findings in HCM
Findings in Athlete's Heart
LV wall thickness and
morphology
Can be >16 mm; can be heterogeneous or
asymmetric across segments
Typically <16 mm, especially in
women; symmetric
Diastolic LV cavity
<45 mm (except in late, dilated phase)
>55 mm
LA size
Enlarged
Normal
LV diastolic filling
pattern
Impaired relaxation (E:A ratio <1, prolonged
diastolic deceleration time)
Normal
Response to
deconditioning
None
LV wall thickness decreases
EKG findings
Very high QRS voltages; Q waves; deep
negative T waves
Criteria for LVH but without
unusual features
Family history of
HCM
Present (except de novo mutations)
Absent
LV: left ventricle; LA: left atrium; LVH: left ventricular hypertrophy.
Adapted from Maron, BJ, Pellicia, A, Spirito, P. Circulation 1995; 91:1596.
25 yo male severe palpitations, lightheadedness,
presyncope playing basketball