Heart Rhythm Community
Differential diagnosis?
About This Community:

A community of people experiencing Heart Rhythm concerns. Ask a question, join a conversation, share experiences: symptoms, management, and treatment.

Font Size:
A
A
A
Background:
Blank
Blank
Blank
Blank Blank

Differential diagnosis?

My cardiologist suspects I have IST - testing for pheochromocytoma came back negative but I seem to have recently developed hypertension, does this change the diagnosis of IST, could anything else be at cause?
4 Comments Post a Comment
Blank
3198987_tn?1349078636
No.
I have IST, and pheochromocytoma is just one cause of IST, but mainly its caused by the sinus node being over sensitive to adrenalin. Blood pressure increase is unrelated to IST as far as I'm aware, but I could be wrong about that. Mainly just the heart rate is effect by IST. How fast is your heart rate at rest? at night?, and while you're walking if you dont mind me asking.
Blank
Avatar_f_tn
It just seems weird that I've suddenly developed hypertension when I usually used to have hypotension.. Without beta blockers, Walking around I'm generally 130ish, walking up stairs 150 and shower at 180. Also I'm on bisoprolol but this doesn't seem to be lowering my bp? My IST is quite debilitating as I have most of the symptoms of heart failure..
Blank
1756321_tn?1377771734
"IST is a diagnosis of exclusion. Almost always, sinus tachycardia is appropriate. Therefore causes of appropriate sinus tachycardia must first be excluded:

Anemia
Pheochromocytoma
Hyperthyroidism
Volume Depletion
Fever
Anxiety Disorder
Medications
Cardiomyopathy"

"Patients who are being considered for IST must have blood or urine tests to exclude anemia, hyperthyroidism, and pheochromocytoma. Medications can also cause heart racing (hydralazine or other vasodilators, too much thyroid hormone replacement, sympathomimetics for asthma or COPD, anticholinergic medications for irritable bowel syndrome, stimulants prescribed for ADD).

A tilt table test is then required to exclude autonomic disorders that can mimic IST: postural orthostatic tachycardia syndrome (POTS) or orthostatic hypotension. This disorder involves abnormal control of blood pressure, and the fast heart rhythm is necessary because of the hypotension that occurs when the patient stands and blood pools in the veins of the legs. Eventually, an EP study may be required to exclude tachycardias arising from near the sinus node, but not from the sinus node itself (5)."

Excerpts from Heart Racing - Inappropriate sinus tachycardia.
Blank
3198987_tn?1349078636
Well the good news is yours seems to not be as serious as others. Some people who have this have their hearts in the 160-170's just from walking across the room. Also while every patient is different I want to add that I to was put on bisoprolol and it did absolutely nothing for my IST. In fact it seemed to make it worse, much worse. Switched to Atenolol and I've seen really good results.
Blank
Post a Comment
To
Top Arrhythmias Answerers
612551_tn?1247839157
Blank
Jerry_NJ
NJ
995271_tn?1408549100
Blank
itdood
PA
1423357_tn?1414258965
Blank
tom_h
Central, MA
1807132_tn?1318747197
Blank
michellepetkus
Chicago, IL
1569985_tn?1328251082
Blank
DeltaDawn23
Ann Arbor, MI
1124887_tn?1313758491
Blank
is_something_wrong
Oslo, Norway
Recent Activity
495284_tn?1333897642
Blank
dominosarah commented on Pip sick...
51 mins ago
242912_tn?1402547092
Blank
Jade59 commented on Pip sick...
1 hr ago
506791_tn?1350343103
Blank
Piparskeggr commented on Pip sick...
1 hr ago
Heart Rhythm Community Resources
RSS Expert Activity
748543_tn?1371753642
Blank
TMJ/TMJ The Connection Between Teet...
Jan 27 by Hamidreza Nassery , DMD, FICOI, FAGDBlank
469720_tn?1388149949
Blank
Abdominal Aortic Aneurysm-treatable... Blank
Oct 04 by Lee Kirksey, MDBlank
242532_tn?1269553979
Blank
The 3 Essentials to Ending Emotiona...
Sep 18 by Roger Gould, M.D.Blank
Top Arrhythmias Answerers
612551_tn?1247839157
Blank
Jerry_NJ
NJ
995271_tn?1408549100
Blank
itdood
PA
1423357_tn?1414258965
Blank
tom_h
Central, MA
1807132_tn?1318747197
Blank
michellepetkus
Chicago, IL
1569985_tn?1328251082
Blank
DeltaDawn23
Ann Arbor, MI
1124887_tn?1313758491
Blank
is_something_wrong
Oslo, Norway