syncope, sudden death and ekg

SAQIB RANA03/12/15

SYNCOPE, SUDDEN DEATH and ECG

“symptom complex comprising a brief loss of consciousness associated with an inability to maintain postural tone that resolves spontaneously without medical intervention”

SYNCOPE

CARDIAC REFLEX MEDIATED

NEUROLOGIC UNKNOWN

CAUSES OF SYNCOPE

29 Y/O MALE PRESENTS AFTER A SYNCOPAL EPISODE

Many other names : IHSS, ASH, HOCMCharacteristic anatomic abnormalities - Hypertrophied, non-dilated LV (normal CXR) - Thickened usually prominent in septumFamilial incidence in 55% of casesAverage age at diagnosis is 30-40 yMortality 3.5% per year

Hypertrophic Cardiomyopathy

Pathophysiology (theories) - Inherited abnormality in myocardium’s response to adrenergic stimulation - Abnormal diastolic function - Subaortic obstruction to cardiac flow - Anterior mitral leaflet obstructs LV outflow


Clinical features - Syncope, chest pain, palpitations, dyspnoea, sudden death Often associated with exertion (not

always!!!) Attributable to dysrhythmias or sudden

reductions in cardiac output Systolic murmur at apex or LLSB - Increases with valsalva, standing - Decreases with trendelenburg and squatting


ECG abnormalities present in 85-93%Definitive diagnosis – DOPPLER ECHO - Doppler helps assess severity of obstruction at rest and with provocative maneuversTreatment - Beta blockers, calcium channel blockers - Amiodarone if ventricular dysrhythmias


30 yo woman presents after a syncopal episode

First described in 1992 by Pedro and Josep Brugada

Associated with sudden cardiac deathIndividuals are usually healthy with

structurally normal heartsGenerally considered a hereditary disease

The Brugada Syndrome

Mortality ~ 10% per year if not treated with Internal cardioverter- defibrillator (ICD)

-Anti arrythmics have NO effect on prognosisSyndrome characterized by -ECG abnl in leads V1-V3 - Polymorphic or monomorphic VT - Structurally normal heart - Familial occurrence in ~ half of patients


ECG findings in V1-V3 - RBBB or IRBBB pattern - ST segment elevation – 2 types -Coved type (most common) - Saddle type - Findings can vary depending on many factorsDefinitive diagnosis - EPS


30 yo woman with palpitations, near- syncope

Ventricular pre-excitation - 0.1-3% population - Classic triad . Shortened PR interval . Widened QRS interval . Delta wave

Wolf Parkinson White Syndrome

WPW Syndrome

WPW Syndrome - NSR

WPW with Orthodromic SVT

After Adenosine

WPW with Antidromic SVT

After shock

Atrial Fibrillation with WPW

Atrial fibrillation - Very rapid irregularly irregular tachycardia (rates may approach 300 beats/min) - Often misdiagnosed as SVT, VT or atrial fibrillation with BBB - Misdiagnosis and treatment with AVN blockers can be deadly


ECG appearance - Irregularly irregular tachycardia - Wide QRS complexes - QRS morphologies vary - Rates may approach 300 BPM


40 yo woman presents after syncope vs. seizure

QT interval vary based on rateCorrected QT interval (QTc) based on Bazett

formula How long is too long? - Major risk occurs in patients when QTc >= 500msec - Major concern : Development of Torsade de pointes

Prolonged QT

What do you do with a prolonged QT? - Search for and treat underlying cause - Congenital/ idiopathic: beta blockersTreatment of torsade de pointes - cardiovert/defibrillate - magnesium bolus and infusion - Overdrive pacing rarely needed - Avoid amiodarone, procainamide, lidocaine

Prolonged QT

Hypokalemia (due to U wave)HypomagnesemiaHypocalcemiaSodium-channel blockers (e.g. Type Ia anti –

arrhytmics, TCAs, etc.)Miscellaneous : Elevated ICP, ACS,

hypothermia, hereditary, etc)

Causes of prolonged QT

Acute coronary syndromeTachyarrythmiasBradyarrhtymias and AV blocksHOCMBrugada syndromeWPW syndromeLong QT interval

SYNCOPE

History of heart failure

Abnormal ECG

Hematocrit less than 30

Shortness of breath

SBP <90 in emergency department

SAN FRANCISCO SYNCOPE RULE

Diagnosis established

YES

Serious diagnosis(cardiac, neurologic)

Non serious diagnosis (Reflex

mediated)

NO

UNEXPLAINED SYNCOPE (risk

stratify)

ACEP GIDELINES

syncope, sudden death and ekg

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