syncope david robertson february 9, 2007. objectives recognize and treat: –severe orthostatic...

Syncope

David RobertsonFebruary 9, 2007

Objectives

• Recognize and treat:– Severe orthostatic hypotension (AF)– Postural tachycardia syndrome (POTS)– Neurally mediated syncope (NMS)

AF POTS NormotensionLabileHBP

HBP

Cardiovascular Continuum

Orthostatic tachycardia

Orthostatic hypotension

~500,000 Americans

~100,000 Americans

NMS

Bradycardia/hypotension~500,000 Americans

AF POTS NormotensionLabileHBP

HBP

Cardiovascular Continuum

Orthostatic tachycardia

Orthostatic hypotension

~500,000 Americans

~100,000 Americans

NMS

Bradycardia/hypotension~500,000 Americans

symptomatic

asymptomatic

AF POTS NormotensionLabileHBP

HBP

Cardiovascular Continuum

Orthostatic tachycardia

Orthostatic hypotension

~500,000 Americans

~100,000 Americans

NMS

Bradycardia/hypotension~500,000 Americans

Severe Dysautonomias

Severe Dysautonomia: Therapy

FIRST LINE:1. Water (+40 mmHg!)2. Food (-30mmHg!)

SECOND LINE:1. Physical Maneuvers2. Exercise (in water)

THIRD LINE:1. Fludrocortisone + Salt2. Pressor Drugs (midodrine)

AF POTS NormotensionLabileHBP

HBP

Cardiovascular Continuum

Orthostatic tachycardia

Orthostatic hypotension

~500,000 Americans

~100,000 Americans

NMS

Bradycardia/hypotension~500,000 Americans Mild Dysautonomias

Postural Tachycardia SyndromePOTS

• Upright symptoms without hypotension• Upright tachycardia (>30 bpm rise)• 500,000 Americans: usually young

women• Antecedent infection; surgery;

pregnancy• Many causes• Tx: low dose (10 mg tid) propranolol

NormalNeuropathic

POTSHyperadrenergic POTS

200

50

200

0

0

60

HR (bpm)

BP(mmHg)

Tilt Angle

AF POTS NormotensionLabileHBP

HBP

Cardiovascular Continuum

Orthostatic tachycardia

Orthostatic hypotension

~500,000 Americans

~100,000 Americans

NMS

Bradycardia/hypotension~500,000 Americans Mild Dysautonomias

Neurally Mediated SyncopeNMS

Transient loss of consciousness

with loss of postural tone

followed by recovery

Syncope

EmotionalDysautonomiaViralSwallowingStandingArrhythmia

0 5 10 15 20 25 30 35 40 45 50

20

40

60

80

100BP

(mm Hg)

ECG

Time (sec)

Hypotension and Sinus Arrest During Venipuncture

Tilt-Induced Bradycardia

EKG

BP

HR

Tilt

Syncope: The Problem

• Loss of consciousness is common

• Long differential diagnosis

• Most benign; some fatal

• Treatment requires diagnosis

Syncope and its Risk

A cardiac etiology conveys risk

Wishwa Kapoor et al. NEJM 1983; 309: 197

CV DISEASES

OTHER CAUSES

Why Do We Faint ?

Blood/Injury/FearPain, blood, medical procedures, fright

After minutes or hours of upright postureGenerally standing or quiet sittingWorse in heat or warm stuffy roomsProbably related to tilt test syncope

Within 30 seconds of arising from sitting or lyingProbably increased conductance in muscle bedCan occur with starting to walk after quiet standing

At or immediately after peak heavy exercise

Syncope: Common Symptoms

Frequent symptoms or signsNausea

Diaphoresis

Pallor

Fatigue

Myoclonic twitches

Frequent presyncopal spells

Improvement on lying down

Syncope Rate in Young Adults

12-48 %

(usually no medical attention)

Syncope

• 3-5% of all ER visits (35% admitted)

• Syncope 1o diagnosis: 1-6% of admits

• 1,000,000 new patients evaluated yearly

• Prevalence: 0.7% in young; 6.0% in old

• Tends to be young women and old men

Syncope Impact

• Recurrent syncope ~ Rheumatoid arthritis

• Maybe home schooling

• Maybe lose your job

• Maybe injury: Falls 4th cause of death

• Pacemaker may make you uninsurable

Neurally Mediated Syncope

• Recurrent (>3) syncope

• No cardiac lesion

• Especially in young

• Rarely life-threatening

• Most gradually improve

Case 1

• 21 year old woman

• Syncope during choir practice

No W/U Required

• If syncope has an obvious cause

• If there is no cause for concern

• But if in clinic: H&P plus ECG

The History

• Complete Description• Other illnesses (virus?)• Type of Onset• Duration of Attacks• Posture• Associated Symptoms• Sequelae

– Prolonged fatigue is almost universal

Case 2

• 21 year old woman

• Syncope during basketball competition

Evaluation of Syncope I

• Is there structural heart disease ?– Hx– PE– ECG– Echo– Monitoring (loop recorder)

Case 3

• 21 year old woman

• Syncope during class

• Father died suddenly at 34

Evaluation Of Syncope II

• Tilt-Table Test

• EP (Electrophysiological) Study

• But……only BP, HR during spontaneous syncope is definitive.

Tilt Table Test• Widely used but rarely

helpful to patients

• Demonstrates what fainting feels like

• 20% of normal subjects test positive

• Positive test doesn’t mean the patient has NMS

• Negative test doesn’t mean patient does not have NMS

Positive Tilt Test

• Hemodynamics– Hypotension– Bradycardia

• Reproduction of Symptoms– Syncope– Pre-syncope

Tilt-Table Test: Positivity

• Normal Subjects• Syncope Patients

13 %*

24-75 %

MEV Petersen Heart 2000; 84: 509

*but ~30% of normals positive at Vanderbilt

Therapy of Syncope

• No drug or device proven helpful• Rate-drop pacemaker• Drugs sometimes employed:

– Propranolol– Fludrocortisone– SSRIs– Midodrine– Water?

No Water Water

0

15

30

45

Ort

ho

stat

ic T

ole

ran

ce (

min

)16 oz Water: Effect on Tilt Tolerance

Vanderbilt University Autonomic Dysfunction Center