The AHA Guidelines and Scientific Statements Handbook

The AHA Guidelines and Scientifi c Statements Handbook

catecholamines) or stimulants (e.g., caffeine, alcohol,
nicotine). It may also refl ect severe underlying
pathologies.
The management of sinus tachycardias primarily
involves identifying the cause and either eliminating
or treating it.

Inappropriate sinus tachycardia
Inappropriate sinus tachycardia is a persistent and
exaggerated increase in resting heart rate unrelated
to the level of physical, emotional, pathological, or
pharmacological stress.

Diagnostic criteria

• Persistent sinus tachycardia (heart rate above
  100 bpm) during daytime with excessive rate increase
  in response to activity and nocturnal normalization
  of rate (confi rmed by 24-hour Holter recording).


• The tachycardia and symptoms are not
  paroxysmal.


• P-wave morphology and intracardiac activation is
  identical to sinus rhythm [5].


• A secondary systemic cause is excluded.

Treatment
The treatment is predominantly symptom-driven
(Table 16.2). The long-term heart rate control after
sinus node modifi cation by catheter ablation has
been reported to be around 66% [6]. A recent
smaller study using a noncontact mapping system
demonstrated effective heart rate control in six of
seven patients [7]. Complications related to catheter
ablation include superior vena cava (SVC) occlu-
sion, phrenic nerve paralysis, and permanent pace-
maker requirement. The diagnosis of postural
orthostatic tachycardia syndrome (POTS) must be
excluded before considering ablation. Recommen-
dations are outlined in Table 16.2.

Sinus node re-entry tachycardia

Sinus node re-entry tachycardia arises from re-

entrant circuits within or close to the sinus node

leading to paroxysmal or nonsustained bursts of

tachycardia that are similar to those in sinus

rhythm.

Clinical criteria include:

• The tachycardia and associated symptoms are par-
  oxysmal and the P-wave morphology is identical to
  sinus rhythm.


• The arrhythmia may be terminated by vagal
  maneuvers or adenosine.


• Intracardiac atrial activation sequence is similar to
  that of sinus rhythm [5].


• Premature atrial stimuli can induce and/or termi-
  nate the arrhythmia.


• Induction of the arrhythmia is not dependent on
  a critical AV-nodal conduction time.

Tr e a t m e n t

Patients with well-tolerated tachyarrhythmias that

are controlled by vagal maneuvers and/or drug

therapy should not be considered for catheter abla-

tion. Catheter ablation, albeit generally successful,

should be reserved for medically refractory cases

[8].

Atrioventricular nodal reciprocating

tachycardia (AVNRT)

AVNRT, the most common form of PSVT, is a re-

entry tachycardia involving the AV node and peri-

nodal atrial tissue. Most commonly the fast pathway

is located near the superior portion of the AV node

and the slow pathway along the septal margin of the

tricuspid annulus at the level of the coronary sinus.

During typical AVNRT (85–90%) the anterograde

conduction occurs over the slow pathway and the

Table 16.2 Recommendations for treatment of inappropriate sinus tachycardia

Treatment Agents/procedure Classifi cation Level of evidence

Medical Beta-blockers I C
verapamil; diltiazem IIa C
Catheter ablation Catheter ablation – sinus node modifi cation/elimination IIb C