The document outlines updated guidelines for pacing in various special conditions, including acute myocardial infarction, cardiac surgery, congenital heart disease, and pregnancy. It discusses the incidence and management of AV blocks post-procedures, indicating a need for observation before permanent pacing in certain cases. Additionally, it highlights specific pacing strategies and considerations in children and those with rare diseases, with a focus on tailored approaches based on individual patient circumstances.

1. Indications for pacing
In
Special conditions
Dr. Ahmed Taha Hussein
M.Sc.Cardiology
Electrophysiology specialist
Assistant lecturer
Zagazig university

2. Updates of the guidelines

3. Specific conditions
▪ Acute myocardial infarction
▪ Pacing after cardiac surgery,transcatheter aortic
valve implantation,and heart transplantation.
▪ Pacing and cardiac resynchronization therapy in
children and in congenital heart disease.
▪ Pacing in hypertrophic cardiomyopathy.
▪ Pacing in rare diseases.
▪ Pacing in pregnancy.
▪ Pacing for first-degree atrioventricular block
(haemodynamic).

4. Acute myocardial infarction
▪ Incidence 3.2% after PCI and thrombolytics.
▪ AWMI associated high degree AV block is
always below Hiss bundle , while IWMI usually
above Hiss bundle .
▪ Usually resolve spontaneously within 2-7 days.
▪ 9% need Permenant pacing later on.
▪ Newely developed Intraventricular condcution
defect usually associated with high mortality due
extensive myonecrosis ... CRT criteria.

5. Acute myocardial infarction

6. Post-cardiac surgery
▪ AV-block occurs in 1-4% cases :
▪ In 8% after repeated surgery , 20 - 40% in
calcific aortic valve and TV-replacement.
▪ SN-dysfunction may occur in CABG, lateral
atriotomy , trans-septal superior approaches to
the MV.
▪ In clincial practice 5-7 days observation period
applied before PPM.

7. TAVI
▪ AV-block post TAVI reaches 14% , especially
with CoreValve prosthesis .
▪ Independant predictors : use of the CoreValve
prosthesis and evidence of conduction system
dysfunction, either pre- existing RBBB or AV
lock at the time of TAVI.
▪ New-onset persistent LBBB is common
following TAVI, but its significance is unclear.
▪ Even TAVI patients meet the criteria for CRT ,
experience is very limited.

8. Heart transplantation
▪ SN-dysfunction is common up to 8% fo cases.
▪ Causes :surgical trauma, sinus node artery
damage, or ischaemia and prolonged cardiac
ischaemic times.
▪ Av-block is less common and is probably
related to inadequate preservation.
▪ Chronotropic incompetence is always present
following standard orthotopic heart
transplantation.
▪ Observation period several weeks , in clinical
consensus 3 weeks .

10. Children
May be early manifestations
is sudden cardiac death,
Adam stokes attackes or
heart failure.
Pacing site RV vs LV
Epicardial vs endocardial

11. Children
SN-dysfunction
CRT
The evidence is
limited to case
reports.
Single site LV
pacing (apex/mid
lateral wall)

12. Hypertrophic cardiomyopathy
▪ uncommon in (HCM), but in context,
can suggest specific aetiologies (for
example, PRKAG2 gene mutations,
Anderson-Fabry disease and
amyloidosis).
▪ CRT may be considered in
individual cases in which there is
some evidence for systolic ventricular
impairment.
RV apical pacing

13. Rare diseases
LQT- syndromes
ICD (with active pacing) is preferable in patients with
symptoms unresponsive
to ß-blocker therapy or pause-dependent ventricular
arrhythmia according to current ICD guidelines.
Muscular dystrophies
Emery-Dreifuss MD
once bradycardia appeared , but thromboebolism are
not preventable by pacing.
athy and mitochondrial diseases , pacing with ICD
back-up is the recommended Other types of
desmopapproach.

14. Pregnancy
▪ Vaginal delivery carries no extra risks in a
mother with congenital complete heart block.
▪ For women who have a stable, narrow,
complex junctional escape rhythm, PM
implantation can be deferred until after delivery.

15. 1st degree AV-block
Prolonged PR interval lead ineffective atrial systole,
and diastolic MR , increased PCWP and pulmonary
congestion.
DDD -- LV dysfunction
Functional Atrial undersensing --shift of P wave

16. ATP-atrial algorithm
Rate-adaptive pacing, which periodically assesses the underlying
intrinsic rate to pace just above it, elevation of the pacing rate after
spontaneous atrial ectopy, transient high-rate pacing after mode
switch episodes and increased post-exercise pacing to prevent an
abrupt drop in heart rate.

17. Thank you