This document discusses chronic atrioventricular block (heart block) in Eastern India. Some key points: - Chronic heart block is a significant problem in Eastern India, where 42% of the population is affected. It places an increased economic burden as more pacemaker implants (PPI) are needed. - Symptomatic heart block most often occurs in the 5th to 6th decade of life in middle-class smokers with sedentary lifestyles. - Common causes of chronic heart block include coronary artery disease, diabetes mellitus, hypertension, cardiomyopathy, valvular heart disease, congenital heart disease, and degenerative disease of the conduction system. - A postmortem study

1. COMPLETE
HEART BLOCK
Dr.Nagula Praveen
Perspective of Chronic heart block in Eastern India, Manotosh Panja

2. PERSPECTIVE
• Chronic AV block significant problem
• Increased economic burden as increased use of PPI
needed.
• Geographical variation in prevalence – 42% population
(Eastern India)
• Symptomatic AV block – 5th to 6th decade, middle class
smokers, sedentary life style.
North zone 15%
Central zone 15%
West zone 10%
South zone 18%

3. Clinical correlations
1.Coronary artery disease
• 15/100 cases (pathology) are due to ischemia – Davies et al.
• Sidden and simons – no more than 20% cases due to IHD.
• Panja et al – 20% cases IHD
• Histopathologically – atherosclerotic changes of the coronary artery thrombosis of
intraluminal vessels.
• MI – Ischemia CHB
• Nodal artery – main bundle destruction (Fulconer and Dean)
• Fibrosis and calcification of the ventricular septum that involves the branching part
of the AV bundle and LBBB – genesis of conduction defect.

4. Demographic profile
Mustard oil consumption 89.3%
Rapseed oil consumption 23.5%
Other oils 11.7%
Smoker 67%
Sedentary habit 90.6%
Bengalee 97.3%
Panja et al.

5. coronary angiography profile in CHB
– Panja et al.
• Age 35-65 years (40 years)
• Males -35,Females -15
• 3 pts < 30% obstruction, 6 pts - >70% significant obstruction
• AV nodal artery visualized in 46 cases (92%)
• Septal perforators identified in all.
• 18% cases due to ischemia
• LAD,RCA,LCX artery involved frequently.
• 41 patients had normal CAG.

6. 2.Diabetes mellitus
• 4/50
• Proliferative changes of diabetic microangiopathy, intramural coronary vessels,
myocardial fibrosis, AV nodal, proximal bundle of His
• Increased fascicular block
• Small vessel changes – lead to CHB
• Deposition of PAS(periodic acid schiff) +ve – endothelial proliferation, basement
membrane thickening
• Small vessels – CHB, large vessel – CAD.

7. 3.Hypertension
• Coronary arteriosclerosis or sclerosis of the left side of cardiac skeleton (increased in
hypertension)
4.Cardiomyopathy
• Idiopathic
• Secondary
• 15% DCMP
• 3% HCM
• Sarcoidosis – important cause of CHB
• Chagas disease
• AV block rarely associated with rheumatoid arthritis,common in ankylosing spondylitis.

8. 5.valvular heart disease
• Calcific aortic stenosis
• Mitral valve disease (uncommon)
• MAC+
• AV – main HIS bundle
6.congenital heart disease
• Isolated abnormality
• CCTGA
• Atrial musculature – AV bundle(absent) – HIS bundle
• Fetal myocarditis
• Idiopathic hemorrhage and necrosis within the conducting tissue
• Degeneration and fibrosis related in some instance to transplacental passage of Anti Ro/Anti SSA

9. Saxena et al
• 44 cases of congenital CHB (AIIMS, Delhi)
• 31 – asymptomatic (group I),13 - syncope, near syncope, convulsions (group II)
• Ventricular rate ( 56.7 ± 13.2 beats/min vs 46.5 ± 6.0 beats/min)
• Wide QRS (2/31 vs 2/13)
• Pauses > 3 sec – infrequent in both
• EP study – suprahisian block on ECG
• Corrected junctional recovery time – no significance
• HR<50/min (during waking hours)
• Wide QRS escape rhythm
• Pause > 3 seconds
PPM

10. • 7. Degenerative disease
• Lev and lenegre
• Impaired function of conduction system
• Degenerative, fibrous changes
• From outside - Lev’s disease
• Primary degeneration – Lenegre disease
• 46/100 cases – Davies et al
• 8/15 cases – Panja et al

11. Erucic acid – The culprit of mustard
oil
• 1-10% of total fatty acids
• Increased concentration in mustard oil
• Sen et al – Human hearts, Bengalees
• Erucic acid was found in normal atheroscleortic heart muscle
• Increased esterified cholesterol (↑DOHA)
• Increased phosphatidyl choline
• Increased sphingomyelin
• Decreased phosphatidyl ethanolamine
• Decreased cardiolipin
• Decreased linoleic acid ( damaged by erucic acid) – inhibits oxidation of long chain fatty
acids – increased TG synthesis, increased cholesterol eructitate
• Lipidosis- acute effect of the mustard oil feedings
• increased collagen synthesis - long term effect

12. Panja et al
Histopathology Primary HTN/OHD Diabetes
Myocardial fibrosis 8 0 1
AV nodal with HIS
bundle fibrosis
5 1 2
Small vessel change 0 0 3
Atherosclerotic changes 0 4 0

13. Causes of chronic AV block – Davies et al
100 cases
Idiopathic bilateral branch fibrosis 46%
Ischaemic coronary artery disease
Destruction of both bundle branches 14%
Destruction of AV node 01%
Cardiomyopathy 13%
Calcific valve disease 8%
Myocarditis 4%
Connective tissue disorder 3%
Amyloidosis 3%
Transfusion siderosis only AV node affected 2%
Congenital heart block only main bundle affected 3%
Gumma of IVS 3%

14. Postmortem study – 15 patients
Age range 30 -90 years
idiopathic 8
IHD 3
Diabetes 4
Hypertension 4
Connective tissue disease 1

15. THANK YOU