Cardiac Causes of Pediatric Syncope: - PowerPoint Presentation

Slide1

Cardiac Causes of Pediatric Syncope:

Eric Johnson, MDApril 18, 2019

Finding the Needle in the Haystack

Slide2

Disclosures

None

Slide3

Objectives

List the most common causes of syncope in pediatric patientsDescribe the mechanism of vasovagal syncope in one sentenceKnow what to do if you suspect an arrhythmia (such as SVT)

Identify features that may be related to a life-threatening cardiac cause

Slide4

Outline

CasesDefinitionEpidemiologyCauses

Dysautonomia

Cardiac

Clinical evaluation

When to consider referral

Slide5

Case #1

13 y.o femaleUnremarkable medical history

Just finished tryouts for volleyball, was standing in a circle during announcement of who made the varsity team

Felt dizzy and lightheaded, rapid palpitations, and “slumped to the floor,” losing consciousness for 1 minute

Afterward, she felt weak and had shaky hands for about 15 minutes

Slide6

Case #2

5 y.o. maleAt age 2, he was running during recess, collapsed, neck extended, eyes “rolled back,” appeared to stop breathing, had fine movements of shoulders and arms, and turned “purple”

Unconscious for 1 minute, seemed confused for a few seconds, then back to baseline

Since then, similar episodes about once a year

Slide7

Definition

A sudden and transient loss of consciousness and postural tone that reverses without intervention.

Slide8

Epidemiology

15 – 25% experience syncope before adulthoodDisproportionately affects teenage females

3% of all pediatric ED visits

Most cases are benign

Rarely, syncope is a harbinger of a life-threatening condition, usually cardiac

Slide9

Pathophysiology

Critical cerebral blood flow = 60 mL/min/100 gCerebral perfusion is usually maintained by autoregulation

When

autoregulation

fails to overcome

a sudden drop in systemic arterial blood pressure

, pre-syncope or syncope occurs

In benign cases, this reconstitutes adequate cerebral blood flow

Slide10

Slide11

Causes

Syncope

Dysautonomia

Vasovagal

Situational

POTS

Orthostatic hypotension

Cardiac

Structural heart disease

Arrhythmia

Myocardial dysfunction

Neurologic

Seizures

Migraines

Brain tumor

AV malformation

Cerebrovascular occlusive disease

Other

Psychogenic

Drugs/Toxins

Anemia

Hypoglycemia

Pregnancy

Breathholding

Syncope “games”

Slide12

Vasovagal

AKA neurocardiogenic, vasodepressor, simple/common faintProdrome

lasts a few seconds to 1 minute

Dizziness, vision changes, nausea, warmth

Syncope typically lasts less than 1 minute

Associated with changes in position

Slide13

Vasovagal

Forceful contractions of an underfilled heart inappropriately activate C-fibers in the heart

Increased parasympathetic tone and decreased sympathetic tone

Bradycardia

, vasodilation, and hypotension

Reduction of cerebral perfusion

Why did my child faint?

Slide14

Vasovagal

“The nerves that help regulate your child’s heart rate and blood pressure were not working properly, which led to a temporary decrease in blood flow to the brain, and subsequent loss of consciousness.”

Slide15

Situational

Pathophysiology and clinical presentation is similar to vasovagalA specific trigger initiates the cascade of autonomic events leading to syncopeSight of blood, pain, fear, hair brushing, urination

Slide16

POTS

Postural orthostatic tachycardia syndromeWithin 10 minutes of assuming an upright position . . . HR increase 30-40, or > 120 beats/min

Associated with exercise intolerance, chronic fatigue, GI problems, headaches, poor sleep, difficulty concentrating, psychological problems

Female: male = 5:1

Slide17

Orthostatic hypotension

Within 3 minutes of assuming an upright position . . . Decrease in systolic BP > 20 mmHgDecrease in diastolic BP > 10 mmHg

Normal adrenergic vasoconstriction is inadequate

Associated with prolonged bed rest or standing

Slide18

Orthostatic vital signs

It takes 15 minutes to do it right!Supine for 5 minutes, then BP + HR

Stand for 3 minutes, then BP + HR

Stand for 7 more minutes, then BP + HR

Slide19

Management of dysautonomia

Not a life threatening condition*There is no cure, although many patients get better

Focus on improving function through:

Increase salt and water intake

Regular exercise

Avoiding triggers and caffeine

Fludrocortisone, midodrine, B-blockers, saline

Slide20

Causes

Syncope

Dysautonomia

Vasovagal

Situational

POTS

Orthostatic hypotension

Cardiac

Structural heart disease

Arrhythmia

Myocardial dysfunction

Neurologic

Seizures

Migraines

Brain tumor

AV malformation

Cerebrovascular occlusive disease

Other

Psychogenic

Drugs/Toxins

Anemia

Hypoglycemia

Pregnancy

Breathholding

Syncope “games”

Slide21

Hypertrophic cardiomyopathy

Ventricular hypertrophy without a hemodynamic causeOne of the most common inherited cardiomyopathies (autosomal dominant)A heterogeneous group of disorders; outcomes depend on type and age

Disproportionately affects teenagers, annual mortality rate = 1%

Slide22

Hypertrophic cardiomyopathy

History:Heart failure (primarily dyspnea on exertion), chest pain (both at rest or with exertion), arrhythmias (both atrial and ventricular), syncope (15-25% of patients), or sudden death

Exam:

Systolic ejection murmur (the less full the ventricle, the louder the murmur)

Systolic

regurgitant

murmur

Slide23

Coronary artery anomalies

Slide24

Coronary artery anomalies

Many variationsIncidence of both coming off the same sinus of Valsalva

~ 0.1 to 0.3% of births

The left coronary coming off the right sinus has higher mortality

Slide25

Coronary artery anomalies

History:Exertional chest pain, syncope, or sudden death

Exam:

Unrevealing

Slide26

Supraventricular tachycardia (SVT)

(Kim and Knight, 2017)

Slide27

SVT

HistoryPalpitations (due to an atrial arrhythmia), lightheadedness, dizziness, syncope, chest pain, sudden death

Exam

Unrevealing

Slide28

Slide29

SVT

If a patient is having an episode of likely SVT (heart rate > 150 beats/min at rest, can be much higher):Take blood pressure if able, consider calling pediatric cardiologist

If doing fine, get an ECG

If not, try vagal maneuvers (such as Valsalva)

Or consider local ED / 911

Slide30

Long QT syndrome

Disorder of ventricular repolarizationMay be congenital (channelopathy) or acquired (often drug-related)

Borderline

QTc

= 0.44 to 0.46

msec

(

Sanatani

et al, 2016)

Slide31

Long QT syndrome

(

Roden

and Spooner, 1999)

Slide32

Long QT syndrome

History:Palpitations, syncope, cardiac arrest, sudden deathFamily history of congenital deafness, drownings

, or accidents without precipitating factors

Exam:

Unrevealing

Slide33

Acute myocarditis

Inflammation of the myocardiumPediatric patients can present with acute or fulminant diseaseMost common etiology is viral infection

Coxsackie A and B, and adenovirus

Syncope may be due to ventricular dysfunction or arrhythmia

Slide34

Acute myocarditis

HistoryRanges from subclinical to sudden deathOften with viral prodrome

Heart failure: dyspnea, exercise intolerance, gastrointestinal symptoms

Exam

Tachypnea, tachycardia,

rales

, gallop,

regurgitant

murmur, friction rub, hepatomegaly

Slide35

Clinical evaluation - History

Details about all of the events surrounding the episode are criticalWas it presyncope

vs

true syncope?

Are there risk factors for dehydration?

How long was the patient unconscious?

Family history of vasovagal episodes, cardiomyopathy, ICD, long QT, sudden death

Slide36

Cross sectional study of 3,445 patients (age < 18)

Presented with syncope or near-syncope to 2 EDs in Atlanta from 2009 to 2013

Slide37

0.1% (n=3) were due to a previously undiagnosed cardiac etiology

2 were SVT and 1 was myocarditis

Slide38

The presence of 2 out of 4 of the following historical features was 100% sensitive and 100% specific

Absence of a

prodrome

Chest pain leading up to syncope

Palpitations leading up to syncope

Syncope during exercise

Slide39

Clinical evaluation - Exam

Distressed?Pale?Count a heart rate (a key skill!)

A heart rate >150 at rest may be SVT, and >220 at rest is SVT until proven otherwise

If possible, take a blood pressure

If possible listen for a heart murmur

Slide40

Referral is indicated for patients who:

received CPR*were cardioverted

(external or ICD)*

have findings consistent with a cardiac cause for syncope

have recurrent episodes consistent with

dysautonomia

would benefit from parental reassurance

Slide41

Case #1

13 y.o. female with palpitations and syncope after volleyball

Supine HR: 58 BP: 108/50

Standing (3 min) HR: 114 BP: 105/81

Standing (10 min) HR: 120 BP: 77/56

POTS

Slide42

Case #2

5 y.o. male with syncope while running

Slide43

Summary

Dysautonomia is the most common cause of syncope in pediatric patientsA thorough history is the key to distinguishing potentially dangerous etiologiesPractice counting high heart rates

Call us with concern for arrhythmia, or syncope with exercise/palpitations/chest pain (especially when there is no prodrome)

If a patient has known cardiovascular disease, make a written plan with family and/or provider

Slide44

References

Allen, H. Syncope: Avoid the Knee-Jerk Echo. AAP Gateway Journals Blog. 2016 Apr 12.Cannon, B, and Wackel

, P. Syncope. Pediatric in Review. 2016 Apr;37(4):159-68.

Hurst, D, et al. Syncope in the pediatric emergency department

–

can we predict cardiac disease based on history alone? J

Emer

Med. 2015;49(1):1-7.

Kim, S, and Knight, B. Long term risk of Wolff-Parkinson-White pattern and syndrome. Trends in Cardiovascular Medicine. Article in press. 2017

Reybrouck

, T, and Ector, H. Syncope and Assessment of Autonomic Function in Children. Moss and Adams’ Heart Disease in Infants, Children, and Adolescents, Chapter 12. Lippincott Williams & Wilkins. 2008.

Roden

, D, and Spooner, P. Inherited Long QT Syndromes. Journal of Cardiovascular Electrophysiology. 1999 Dec;10(12):1664-83.

Sanatani

, S, et al. Canadian Cardiovascular Society and Canadian Pediatric Cardiology Association Position Statement on the Approach to Syncope in the Pediatric Patient. J CJC. Article in press. 2016.

UpToDate, 2017.

<https://www.texaschildrens.org/departments/anomalous-aortic-origin-coronary-artery-aaoca>

Slide45

Thank You

Slide46

Pediatric Cardiology(541) 222-6160 24/7/365

Outpatient clinic consultations

Pediatric echocardiograms

Pediatric ECGs and rhythm monitors

Email or phone consultations

Misty Carlson, MD

mcarlson2@peacehealth.org

Eric Johnson, MD

ejohnson@peacehealth.org