LBBB VT: It’s Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

• LBBB morphology wide QRS tachycardia: Why VT?• QRS width 160 ms

• Intrinsicoid deflection = 80 ms

• Atypical QRS pattern for LBBB: Observe precordial lead polarity V1 (negative), V2 (positive), v3-6 (negative)

• QS in leads v5, v6

Dr Jaspal Arneja DM, Dr Vinay Pandey MD

ARVD / ARVC : MORPHOLOGY

• Autosomal dominant inheritance,

variable penetrance

• Mutation in genes encoding for

desmosomal proteins

• Replacing cardiomyocytes by

adipose and fibrous tissue

• >1 mutation, worse outcome

Prevalence 1 in 5000

SCD IN YOUNG ADULTS

ARVD / ARVC: DISEASE PROGRESSION

• Phase 1 (Concealed): subtle RV structural changes, ±VAs

• Phase 2 (overt electrical disorder): symptomatic (PVCs / NSVT) or life-

threatening VAs with obvious RV morpho-functional abnormalities

• Phase 3 (RV failure): progression of RV disease (dyspnea)

• Phase 4 (biventricular failure): pronounced LV disease (fluid overload)

Presentation: Palpitations(VAs), Syncope, SCD

Presentation: HF

Onset 2nd or 3rd decade

ECG in Sinus rhythm in ARVC

• P wave: notched, widened (p wave duration>110 ms), flat or small peaked P wave.

• PR interval: Prolonged. First degree AV block in 16% patients.

• QRS complex: QRS prolongation (duration>110 ms) and terminal S wave prolongation (>55ms) in V1-V3.

• Fragmented QRS (notch before the end of R or S wave) seen in 51%

• Epsilon wave: most specific finding. Seen in 30% pts