Page 70 - Clinical Pearls in Cardiology

58 Clinical Pearls in Cardiology

Pheochromocytoma is responsible for less than
0.1% of cases of hypertension. This tumor is most
commonly located in the adrenal medulla. There is
a useful ‘rule of tens’ in pheochromocytoma. About
10% of pheochromocytomas are malignant, about
10% of these tumors are extra-adrenal in location (i.e.
located elsewhere in the sympathetic chain) and about
10% are familial (autosomal dominant inheritance).
The disease is characterized by episodic hypertension,
often associated with attacks of postural hypotension in
between the episodes of hypertension.
43. What do you know about the phenomenon of
‘auscultatory gap’?
The sounds generated by the turbulent blood flow within
an artery that is compressed by the inflated cuff of the
sphygmomanometer are called the Korotkoff sounds.
There are five phases to these sounds. In some elderly
persons with hypertension, a silent interval may occur
between the end of the first and beginning of the third
phase of the Korotkoff sounds. This silent interval is
called as the “auscultatory gap”. This silent gap may
cause underestimation of the systolic blood pressure,
sometimes, by as much as 50 mm Hg. Because this gap
occurs only with auscultation, it is recommended that
a preliminary determination of systolic blood pressure
be made by palpatory method, and the cuff inflated
by about 30 mm Hg above this value for auscultatory
measurement of systolic blood pressure.
44. How will you initiate antihypertensive drug in a patient
with hypertension without any compelling indication?
Tolerability, availability and cost are considered when
proposing the order of drug therapy in hypertension.
If no compelling indication exists for the use of a