Re: 27year old w/ sinus tachycardia

Posted By Denise on December 22, 1998 at 13:50:59:

In Reply to: 27year old w/ sinus tachycardia posted by Jo Bryan on December 22, 1998 at 00:46:09:






My 27 year old daughter has had tachycardia for 10 years which has worsened in the past few months, recently causing
her to collapse when at a bowling party.  She was taken by ambulance to ER found to have heart rate 200, EKG abnormal
on lst reading, moving to normal in 2 hours.  Local cardiologist found MVP, & after 24 and 48 hr holter monitors showed
heart rates 70-170 even sleeping, he said is is sinus tachycardia, caused from MVP.  Went to EP in Dallas, who agreed it is
sinus tachycardia, but not caused by MVP and ordered event monitor, which she used 30 days.  Still no definitive diagnosis, and
he wants her to wear it another 30 days.  Is this necessary?  She is most impatient with this process, and losing faith in docs
(her dad is one).  What would you tell your daughter?  Is this life threatening?  What about the collapse?  Any suggestions?  
Thanks.
Hi Jo,
I too have a sinus tachycardia problem.  I've asked questions on this forum and here is what Dr. CRC (from this forum) attached to one of my questions.  The doc will answer your questions, but this is just FYI.
I also tried to e-mail you, but got a "host unknown" error.  Feel free to e-mail me by clicking above.  This is definitely not a fun problem to have!
Have a nice holiday!
Denise O.
Here is what Dr. CRC attaches:
There are many causes of tachycardia (fast heart beat) and they can be
divided roughly into sinus (originating from the sinus node or heart's
natural pacemaker) and non-sinus tachycardias.
Nonsinus tachycardias are either supraventricular (coming from the
upper chambers of the heart) or ventricular (coming from the lower
chambers of the heart). Supraventricular tachycardias include:
paroxysmal supraventricular tachycardia, atrial flutter, atrial
fibrillation and AV nodal tachycardia. Ventricular tachycardias are
more serious in nature and are due to a rapid depolarization of the
ventricles.
Sinus tachycardia is defined as a heart rate of greater than 100 beats
per minute originating from the sinus node. Sinus tachycardia is
classified as either appropriate or inappropriate. There are many
causes of appropriate sinus tachycardia such as exercise, anxiety,
panic attacks, dehydration, deconditioning, volume loss due to bleeding
or other loss of body fluids, hyperthyroidism, electrolyte
abnormalities and many other conditions.
Inappropriate sinus tachycardia can only be diagnosed when all causes
of appropriate sinus tachycardia have been ruled out. It is not clear
what causes inappropriate sinus tachycardia but possible etiologies are
an increase in the rate at which the sinus node depolarizes and an
increased sensitivity to adrenaline. Once the diagnosis has been made
by ruling out all of the potential causes of appropriate sinus
tachycardia there are several treatment options. If the symptoms are
not overly concerning no treatment needs to be done. There is no
increase in morbidity or mortality in persons with this condition and
they can expect to have a normal life-span. For persons in whom the
symptoms are unbearable medications such as beta blockers or calcium
channel blockers can be used, usually with good results.  In the rare
person unable to tolerate medical treatment catheter ablation (burning)
of the sinus node with insertion of a pacemaker or surgical removal of
the sinus node have been used in the past. Newer techniques are being
developed using catheter ablation to modify and not destroy the sinus
node thus avoiding the need for a pacemaker. This procedure is still in
it's infancy and should only be undertaken at a major medical center
after consultation with an electrophysiologist.
Below are some journal articles that address this topic in depth. Your
local medical library should be able to help you find copies.
Review Articles:
Krahn AD. Yee R. Klein GJ. Morillo C. Inappropriate sinus tachycardia:
evaluation and therapy. Journal of Cardiovascular Electrophysiology.
6(12):1124-8, 1995 Dec.
Abstract
Inappropriate sinus tachycardia is an ill-defined clinical syndrome
characterized by an increased resting heart rate accompanied by an
exaggerated response to exercise or stress. It is not associated with
underlying structural heart disease. The mechanism may involve a
primary abnormality of the sinus node demonstrating enhanced
automaticity or, alternatively, a primary autonomic disturbance with
increase sympathetic activity and enhanced sinus node beta-adrenergic
sensitivity. The diagnosis of inappropriate sinus tachycardia is one of
exclusion. It is most common in young females, with a disproportionate
number employed in the health care field. Autonomic and
electrophysiologic testing may be required in selected individuals to
clarify the mechanism and rule out sinus node reentry or right atrial
tachycardia. Therapy of inappropriate sinus tachycardia is empiric.
Pharmacologic approaches include beta blockers or verapamil.
Radiofrequency catheter ablation of the superior portion of the sinus
node shows promise as a useful alternative in patients with refractory
symptoms.

Sims JM. Miracle V. Sinus tachycardia. Nursing. 26(6):49, 1996 Jun.

Articles Concerning Catheter Treatment Options.
Lee RJ. Kalman JM. Fitzpatrick AP. Epstein LM. Fisher WG. Olgin JE.
Lesh MD. Scheinman MM. Radiofrequency catheter modification of the
sinus node for "inappropriate" sinus tachycardia. Circulation.
92(10):2919-28, 1995 Nov 15.
BACKGROUND: Radiofrequency catheter ablation is the treatment of choice
for patients with paroxysmal supraventricular tachycardias refractory
to medical therapy. However, in symptomatic patients with inappropriate
sinus tachycardia resistant to drug therapy, catheter ablation of the
His' bundle with permanent pacemaker insertion is currently applied. We
evaluated the safety and efficacy of radiofrequency modification of the
sinus node as alternative therapy for patients with inappropriate sinus
tachycardia. METHODS AND RESULTS: Sixteen patients with disabling
episodes of inappropriate sinus tachycardia refractory to drug therapy
(4.2 +/- 0.3 drug trials) underwent either total sinus node ablation or
sinus node modification. The region of the sinus node was identified as
the region of earliest atrial activation in sinus rhythm during
electrophysiological study.  This region was further defined by use of
intracardiac echocardiography (ICE) in 9 patients, in whom it was found
that an ablation catheter could be guided reliably and maintained on
the crista terminalis. Radiofrequency energy was delivered during
tachycardia between either a standard 4-mm or custom 10-mm
thermistor-imbedded catheter tip and a skin patch. Total sinus node
ablation was performed successfully in all 4 patients in whom it was
attempted and was characterized by a junctional escape rhythm.
Sinus node modification was successfully achieved in all 12 patients in
whom it was attempted and was characterized by a 25% reduction in the
sinus heart rate. For the group as a whole, exercise stress testing
after ablation revealed a gradual chronotropic response, with a
significant reduction in maximal heart rate (132.8 +/- 6.5 versus 179.5
+/- 3.6 beats per minute [bpm]; P < .001) without evidence of an
exaggerated heart rate response to a light workload (103.0 +/- 4.1
versus 139.5 +/- 3.5 bpm; P < .001). Twenty-four-hour ambulatory ECG
monitoring revealed a significant decrease in maximal heart rate and
mean heart rate after ablation (167.2 +/- 2.6 versus 96.7 +/- 5.0 bpm,
P < .001, and 125.6 +/- 5.0 versus 54.1 +/- 5.3 bpm, P < .001,
respectively). There was a significant decrease in the number of
applications of radiofrequency energy required in patients undergoing
modification of the sinus node when guided by ICE compared with
fluoroscopy alone (3.6 +/- 0.8 versus 10.4 +/- 2.1; P < .01) as well as
a decrease in fluoroscopy time (33.0 +/- 9.5 versus 58.5 +/- 8.4
minutes). After a mean follow-up period of 20.5 +/- 0.3 months, there
were no recurrences of inappropriate sinus tachycardia in patients who
underwent a total sinus node ablation.  However, 2 patients who had a
total sinus node ablation subsequently required permanent pacing
because of symptomatic pauses, and 1 patient developed an ectopic
atrial tachycardia. After a mean follow-up of 7.1 +/- 1.7 months, there
were two recurrences of inappropriate sinus tachycardia in patients who
underwent sinus node modification. However, no significant bradycardia
or pauses were observed. Complications encountered during the study
included 1 patient who developed transient right diaphragmatic
paralysis and another patient who developed transient superior vena
cava syndrome. CONCLUSIONS: Sinus node modification is feasible in
humans and should be considered as an alternative to complete
atrioventricular junctional ablation for patients with disabling
inappropriate sinus tachycardia refractory to medical management.
Sinus node modification may be aided by ICE.
Jayaprakash S. Sparks PB. Vohra J. Inappropriate sinus tachycardia
(IST):  management by radiofrequency modification of sinus node.
Australian & New Zealand Journal of Medicine. 27(4):391-7, 1997 Aug.
BACKGROUND: Inappropriate sinus tachycardia (IST) is a rare form of
supraventricular arrhythmia. It can cause disabling symptoms and may be
refractory to medical treatment. In symptomatic drug refractory
patients, sinus node excision or total ablation of the sinus node with
permanent pacemaker implantation was the only therapeutic option.
Recently, radiofrequency (RF) modification of the sinus node has been
reported to be an effective treatment for this condition. AIM: To
present our experience with sinus node modification using RF energy in
the management of IST.
METHODS: Between 1989 to 1996 three patients (two females and one
male), aged 28-36 years were diagnosed with symptomatic IST. All had
failed multiple drugs and hence underwent sinus node modification using
RF. In the first two patients, the site of RF application was guided by
anatomical landmarks using fluoroscopy to localise the presumed most
superior portion of the crista terminalis and also the earliest site of
atrial activation. In the third patient, a 20 pole electrode catheter
was used to map the crista terminalis and guide the ablation. Success
was defined by 20-30% reduction in the heart rate with normal atrial
activation sequence after ablation. RESULTS: The three patients
described here had IST by clinical, electrocardiographic and
electrophysiological criteria and were refractory to multiple
antiarrhythmic drugs. The number of RF applications were 11, 15, and
three applied at the site of earliest atrial activation for the control
of heart rates. Patient 3 had a early recurrence at one month and
underwent repeat sinus node modification (five RF applications). All
three patients who underwent RF modification of the sinus node had a
successful outcome. The procedure was uncomplicated and the patients
remain asymptomatic during follow up (20, 12 and three months) with
satisfactory control of heart rate, although one patient requires
atenolol which was previously ineffective. CONCLUSIONS:  RF
modification of the sinus node is feasible and effective for IST, and
should be the treatment of choice in patients refractory to medical
therapy.
Surgical treatment (Only as a last resort) Esmailzadeh B. Bernat R.
Winkler K. Meybehm M. Pfeiffer D. Kirchhoff PG.  Surgical excision of
the sinus node in a patient with inappropriate sinus tachycardia.
Journal of Thoracic & Cardiovascular Surgery. 114(5):861-4, 1997 Nov.