Sudden Cardiac Death What an electrophysiologist thinks a

cardiologist should know

Steven J. Kalbfleisch, M.D.

Medical Director Electrophysiology Laboratory

Ross Heart Hospital

Wexner Medical Center

Sudden Cardiac Death (SCD) Death within 1hr of sx onset

300,00-400,000 Victims Annually (0.1% of population)

SCD accounts for 50% of all cardiac related deaths and

15% of total mortality in US.

Primary Cause is Arrhythmic

Older data - VT/VF (75%), Asystole/PEA (25%)

Newer data - Asystole/PEA (50%)

Recurrence Rate is up to 30% annually among Survivors

Incidence of SCD in Specific Populations

Myerburg RJ. Circulation.1998;97:1514-1521.

GROUP

300,000

Patients with high coronary-risk profile

Patients with previous coronary event

Patients with ejection fraction < 35%, congestive heart failure

Patients with previous out-of-hospital cardiac arrest

Patients with previous MI, low EF, and VT

General population

200,000 100,000 0

No. of Sudden Deaths Per Year

30 25 20 15 10 0

Incidence of Sudden Death (% of group)

5

Over half of

SCA victims

have no prior

symptoms

Severity of Heart Failure Modes of Death

LANCET. 1999;353:2001-07.

12%

24%

64%

CHF

Other

Sudden Death n = 103

NYHA II

26%

15%

59%

CHF

Other

Sudden Death

n = 103

NYHA III

56%

11%

33%

CHF

Other

Sudden Death n = 27

NYHA IV

Sudden Death Is Frequently Due To Ventricular

Tachycardia Degenerating To Ventricular Fibrillation

The rhythm recorded depends on the timing of the recording

24 hr Holter on during CHF Event /

Respiratory Arrest

Just because asystole occurred doesn’t

mean that is what they died from!

III

V1

AVB – An uncommon cause of SCD

Torsades with High Grade AVB

Infranodal CHB

Sudden Cardiac Death

400,000/year

Provoking Factor Underlying Heart Disease

80% No Acute MI

20% Acute

MI

80% CAD

15%

Other

5%

None

• Non-ischemic Cardiomyopathy

• Inherited Disorders

– LQTS, Brugada’s, HCM, ARVD

Ventricular Arrhythmias as a Cause of

Syncope / SCD

• Monomorphic Ventricular Tachycardia • Scar related

• Polymorphic VT / Ventricular fibrillation • Acute MI / ischemia / NICM

• Torsades de Pointes • Congenital long QT

• Drug / Metabolic induced

65 yo M with CAD, s/p CABG with syncope and WCT

Sustained monomorphic VT = Scar related

65 yo M with CP in ER – PVMT / VF = think ischemia

68 y/o woman, Hx PAF / CAD, LVEF 50%

Rx’d with Sotolol 120mg Bid

Iatrogenic SCD!

No mortality benefit with any antiarrhythmic

in any patient group

Proven Treatment for SCD

• Bystander CPR

• External defibrillators (AEDs)

• Medications - BBs and ACEI in high

risk groups (Post MI, CHF)

• ICD therapy (including CRT in select

patients)

JACC 1997;30:1500-5.

Out of Hospital Cardiac Arrest

Home

399

On Street

47

Public Place

31

Other

20

Work

4

Site of Cardiac Arrest

The Maastricht Study Holmberg et al,

AJC 1999

Time from Cardiac Arrest to

First Defibrillation

ICD components

Lead + Device Transvenous SICD

ICD shock

ICD Indications – Black / White

• OK to Implant – Secondary Prevention (aborted SCD, Sustained VT,

syncope in high risk group)

– EF < 30% / CAD / Prior MI

– EF < 35% / CHF (class II / III),

– CHF (class IV) if implanting with CRT

• Not OK to Implant (for Primary Prevention) – MI < 40 days

– Revascularization < 3 months

– CHF < 3 months

– Class IV CHF or Class I Non-ischemic

– Life expectancy < 1 yr

Recorded 3 weeks after DC home

65 yo M with VF / Aborted SCD

Acute LAD Total Occlusion Rx’d with PTCA

EF = 25% post MI, NSVT x 25 beats

SCD in Young Athletes 1435 athletes 1980 - 2005

Maron et al, Circ 2007

Note: CAD is still the predominate cause of SCD in older athletes

What can you catch with an ECG?

• HCM – The largest group in the USA

• ARVD – the Largest group in Italy

• The “Channelopathies”

– Long QT

– Brugada Syndrome

25 yo M had SCD event during

basketball game

Late gadolinium

enhancement

LV

RV

CMR

HCM with septum 3cm

and LGE

26 yo athlete presented with LB WCT / Syncope ECG after conversion

ARVD – Episolon Waves / T Wave changes / CMR

RV CMR

RV dilation, RVEF = 40%, LVEF = 54%

40 yo M presented after a syncopal episode ST-segment Elevation - V1 Through V3 – Type I Brugada

Family Hx of SCD – Uncle died in sleep

The Evolution of SCD therapy Drug vs Device

Major ICD Trials

Recent CABG

< 40 days from MI

*

*

*

= secondary prevention *