Syncope, sudden death and ekg

1. SAQIB RANA
03/12/15

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

3. CARDIAC
REFLEX
MEDIATED
NEUROLOGIC UNKNOWN

5.  Many other names : IHSS, ASH, HOCM
 Characteristic anatomic abnormalities
- Hypertrophied, non-dilated LV (normal CXR)
- Thickened usually prominent in septum
 Familial incidence in 55% of cases
 Average age at diagnosis is 30-40 y
 Mortality 3.5% per year

6.  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

7.  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

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

10.  First described in 1992 by Pedro and Josep Brugada
 Associated with sudden cardiac death
 Individuals are usually healthy with structurally
normal hearts
 Generally considered a hereditary disease

11.  Mortality ~ 10% per year if not treated with Internal
cardioverter- defibrillator (ICD)
-Anti arrythmics have NO effect on prognosis
 Syndrome characterized by
-ECG abnl in leads V1-V3
- Polymorphic or monomorphic VT
- Structurally normal heart
- Familial occurrence in ~ half of patients

12.  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 factors
 Definitive diagnosis - EPS

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

24.  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

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

27.  QT interval vary based on rate
 Corrected 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

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

29.  Hypokalemia (due to U wave)
 Hypomagnesemia
 Hypocalcemia
 Sodium-channel blockers (e.g. Type Ia anti –
arrhytmics, TCAs, etc.)
 Miscellaneous : Elevated ICP, ACS, hypothermia,
hereditary, etc)

30.  Acute coronary syndrome
 Tachyarrythmias
 Bradyarrhtymias and AV blocks
 HOCM
 Brugada syndrome
 WPW syndrome
 Long QT interval

31. History of heart failure
Abnormal ECG
Hematocrit less than 30
Shortness of breath
SBP <90 in emergency department

32. Diagnosis
established
YES
Serious
diagnosis(cardiac,
neurologic)
Non serious
diagnosis (Reflex
mediated)
NO
UNEXPLAINED
SYNCOPE (risk
stratify)