Transcript Document

Approach to a young
hypertensive patient
- Investigations and diagnosis
Dr.
Overview
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Introduction
General Approach to the Patient
Most Common Causes of Secondary HT by Age
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Children and Adolescents
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(Birth to 18 Years of Age)
 Renal parenchymal disease
 Coarctation of the aorta
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Young Adults
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(19 to 39 Years of Age)
 Takayasu’s arteritis in India (Asia)
 Fibromuscular dysplasia
 Thyroid dysfunction
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Algorithm for initial evaluation of secondary HT
Conclusions
Introduction
Classification of Hypertension:
The Seventh Report of the Joint National Committee
(JNC VII)
SBP, systolic blood pressure;
DBP, diastolic blood pressure
NIH Publication No. 045230 August 2004
General Approach to the Patient
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Confirm that the patient’s blood pressure
(BP) has been accurately measured using
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Correct positioning with an appropriately sized
cuff
If white coat hypertension suspected
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Ambulatory BP monitoring can be useful to
rule out
Hypertension. 2003;42(6):1206-1252,
Am Fam Physician. 2009;79(10):863-869.
General Approach to the Patient (Contd)
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Important to review
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The patient’s diet and medication use for other
potential causes of HT
Excessive consumption of
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Sodium,
Licorice (Hindi: Jethimadh, Mulhathi), or
Alcohol is known to increase BP
HT - hypertension
J Clin Hypertens (Greenwich) 2008;10(7):556-566.
General Approach to the Patient (Contd)
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Many drugs affect BP
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A trial period off of a potentially offending medication
may be all that is needed to reduce BP
Am Fam Physician 2010 Dec 15;82(12):1471-8.
General Approach to the Patient (Contd)
If these potential contributors to
hypertension have been excluded and
 Concern for secondary hypertension
remains, the physician can investigate for
potential physiologic causes
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Am Fam Physician 2010 Dec 15;82(12):1471-8.
Most Common Causes of Secondary
Hypertension by Age*
Must remember
that these are
not absolute
categories;
There may be
overlap of causes
between age
groups
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Signs and Symptoms That Suggest Specific
Causes of Secondary Hypertension
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Signs and Symptoms That Suggest Specific
Causes of Secondary Hypertension (Contd)
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Children and Adolescents
(Birth to 18 Years of Age)
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Renal parenchymal disease
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Coarctation of the aorta
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Renal parenchymal disease
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Most common cause of hypertension in
preadolescent children
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In this age group, such renal pathology
includes
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Glomerulonephritis
Congenital abnormalities and
Reflux nephropathy
Sometimes the resulting hypertension is
not apparent until young adulthood, so
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This etiology should still be considered in the
differential diagnosis outside of childhood
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Renal parenchymal disease (Contd)
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Initial evaluation for suspected renal
parenchymal disease should include
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Measurement of blood urea nitrogen and
creatinine levels
A urinalysis
Urine culture and
Renal ultrasonography
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Coarctation of the aorta
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The second most common cause of HT in
children, and
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Although coarctation may present acutely
in the neonate as congestive heart failure,
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Two to five times more common in boys
It is typically diagnosed around five years of
age with the onset of HT or a cardiac murmur
Rarely, mild cases of coarctation have
occurred in adults
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Coarctation of the aorta (Contd)
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Discrepancies between bilateral brachial,
or brachial and femoral blood pressures,
suggest coarctation
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Chest radiography
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In younger patients, may be nonspecific,
whereas
In adults the classic “three” sign or rib
notching may be evident
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Coarctation of the aorta (Contd)
Red arrows - rib notching
caused by the dilated
intercostal arteries
Yellow arrow - the aortic
knob,
Blue arrow - the actual
coarctation and
Green arrow -the poststenotic dilation of the
descending aorta
Close up of upper thorax in a patient with
Coarctation of the Aorta.
Coarctation of the aorta (Contd)
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Transthoracic echocardiography
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Sufficient for diagnosis in children, given their
smaller body habitus, and
Useful to concurrently evaluate for left
ventricular hypertrophy
Magnetic resonance imaging (MRI) is
increasingly common and
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The preferred imaging method in adults
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Young Adults
(19 to 39 Years of Age)
Takayasu’s arteritis in India (Asia)
 Thyroid dysfunction
 Fibromuscular dysplasia
 Renal parenchymal disease
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Takayasu’s arteritis (TA)
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Although TA has a worldwide distribution, it is
observed frequently in Asia than in North
America
The most common cause of RVH in
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India
China
Korea
Japan and other countries of South East Asia
RVH-Renovascular hypertension
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Indian studies
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TA
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In one study from Chandigarh by Sharma et al
Takayasu’s arteritis was found as the leading
cause of hypertension in hospitalised patients
Involvement: 50% cases bilateral and in 28%
unilateral
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Indicating that this condition must be kept in mind
as one of the important causes, especially in
northern India, whenever one is considering RVH
Angiology 1985; 36: 370-8
TA: Indian studies (Contd)
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Study at PGI Chandigarh
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205 patients with hypertension were shown to
have a renovascular aetiology over 16 years.
Of these,
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125 (61 %) Takayasu's arteritis,
58 (28.3 %) fibromuscular dysplasia,
16 (7.8 %) atherosclerosis,
five (2.4 %) polyarteritis nodosa and
one (0.5 %) renal artery aneurysm
Q J Med. 1992;85:833-43.
TA: Indian studies (Contd)
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Study at PGI Chandigarh (Contd)
Among patients with TA, males were affected as commonly
as females
The mean age of these patients at the time of detection
was 26.8 +/- 8.6 years (range 5-52 years)
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Type I arteritis in nine (7.2 %),
Type II in 40 (32 %) and
Type III in 76 (60.8 %) patients
The abdominal aorta was involved in 117 (93.3 %) patients
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TA was associated with ulcerative colitis in two patients and
with renal amyloidosis and focal segmental glomerulosclerosis
with a nephrotic syndrome in one patient each
Q J Med. 1992;85:833-43.
TA: Indian studies (Contd)
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Seth GS Medical College & KEM Hospital,
Parel, Mumbai
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Medical records of 54 patients with RVH
showed
Aortoarteritis 44 (81.5%),
Atherosclerotic disease 7 (31.5%) and
Fibromuscular dysplasia 3 (5.6%) as etiologies
of RVH
32nd Annual Conference of Indian
Society of Nephrology September, 2001
TA (Contd)
TA is a chronic vasculitis involving mainly
the aorta and its branches, as well as the
pulmonary and coronary arteries
 Classical definition of TA is that of
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Chronic, progressive, inflammatory, occlusive
disease of the aorta and its branches
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Aetiology
Remains enigmatic
 Various mechanisms such as postinfective, autoimmune, ethnic
susceptibility and a genetic predisposition
have been postulated
 Autoimmunity appears to be the most
plausible mechanism
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Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Diagnostic criteria
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Following table mentions
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Sensitivity and specificity for the various
diagnostic criteria
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Diagnostic
criteria
Modified diagnosis criteria
for TA: Sharma et al
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Diagnostic
criteria (Contd)
Modified diagnosis criteria
for TA: Sharma et al
(Contd)
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Diagnostic criteria (Contd)
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Type I is limited to the aortic arch and its
branches
Type II affects the descending thoracic
and abdominal aorta
Type III is extensive form involving the
arch and the thoracic and abdominal
aorta
Type IV is designated to those cases with
pulmonary involvement in addition to the
features of type I, II, or III
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Clinical features
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TA classically progresses through 3
stages:
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An early systemic illness usually associated
with constitutional symptoms and fever
A vascular inflammatory phase
The inflammation settles down or burns out
Eur J Vasc Endovasc Surg 2007;33, 578-82
TA: Clinical features (Contd)
Eur J Vasc Endovasc Surg 2007;33, 578-82
Fibromuscular dysplasia (FMD)
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10% of cases of RVH are due to FMD
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Mainly in younger women
Bilateral renal artery involvement with
extension into the distal portion of the artery
and its branches is common
US Nephrology 2009;5(2):56–59,
Proc (Bayl Univ Med Cent) 2010;23(3):246–49
FMD (Contd)
Vascular disorder of unknown etiology that
has a predilection for the renal arteries,
causing narrowing that leads to decreased
renal perfusion
 In young adults, particularly women,
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FMD is one of the most common causes of
secondary hypertension
Patients with renal artery stenosis may
have an audible high-pitched holosystolic
renal artery bruit
Am Fam Physician 2010 Dec 15;82(12):1471-8.
FMD (Contd)
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Compared with patients without such a
finding, those in whom a renal artery bruit
is detected have a relative risk of
approximately 5.0 for renal artery
stenosis;
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these patients should all have further testing
Am Fam Physician 2010 Dec 15;82(12):1471-8.
FMD (Contd)
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Although angiography is the diagnostic
standard for detecting renal artery
stenosis,
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it is invasive and should not be used as an
initial diagnostic test
MRI with gadolinium contrast media and
computed tomography (CT) angiography
are equally accurate in visualizing stenosis
Am Fam Physician 2010 Dec 15;82(12):1471-8.
FMD (Contd)
CT angiogram obtained in
a 45 y.o. woman presenting
with new onset RVH
Aneurysmal dilation and
vascular occlusion beyond
a fibromuscular lesion is
present in the right kidney
associated with loss of
perfusion to the entire upper
pole of the kidney
Fibromuscular Dysplasia, before
and after PTRA
Safian & Textor. NEJM 344:6;
FMD (Contd)
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MRI
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Does not use radiation and can determine the
physiologic degree of stenosis
Can also be used for patients with poor renal function,
particularly when used without gadolinium, although
with a slight decrease in sensitivity and specificity
If MRI and CT angiography are contraindicated,
renal Doppler can be used;
Doppler
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Provides useful information regarding blood flow, but
Its accuracy is affected by body habitus and operator
skill
Am Fam Physician 2010 Dec 15;82(12):1471-8.
FMD (Contd)
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Captopril-augmented renography has
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Poor sensitivity and specificity, which translate
into likelihood ratios close to 1.0,
No longer considered a good first-line test
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Thyroid dysfunction
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Thyroid hormone affects cardiac output
and systemic vascular resistance, which in
turn affect BP
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Hypothyroidism can cause an elevation in
diastolic BP, whereas
Hyperthyroidism can cause an isolated
elevation of systolic BP, leading to a widened
pulse pressure
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Thyroid dysfunction Contd)
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Although hypothyroidism is one of the
more common secondary causes of
hypertension in young adults,
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There is actually an increased incidence of
hypothyroidism with age, peaking in a
patient’s 60s
In contrast, hyperthyroidism is
significantly associated with elevated BP in
20- to 50-year-olds
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Thyroid dysfunction
(Contd)
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Because thyroid dysfunction occurs across
multiple age groups, testing for it should
be considered if there are any suggestive
symptoms
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Thyroid-stimulating hormone is a sensitive
marker used for initial diagnosis of either
condition
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Accuracy of
Diagnostic Tests
for Causes
of Secondary
Hypertension
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Algorithmic
approach to the
initial evaluation
of patients with
suspected
secondary
hypertension
CT = computed
tomography; MRI
= magnetic
resonance
imaging; TSH =
thyroid-stimulating
hormone
Am Fam Physician 2010 Dec 15;82(12):1471-8.
Conclusions
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Prevalence and etiology of hypertension varies
with age
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Young/early onset hypertension should be
approached with evaluation of
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Symptoms
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Examination findings
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(e.g., flushing and sweating s/o pheochromocytoma),
(e.g., a renal bruit s/o renal artery stenosis), or
Laboratory abnormalities
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(e.g., hypokalemia s/o aldosteronism)
s/o- suggestive of
Conclusions
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In young adults, particularly women, renal artery
stenosis caused by fibromuscular dysplasia is one
of the most common secondary etiologies
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(Contd)
FMD can be detected by abdominal magnetic resonance
imaging or computed tomography
Takayasu’s arteritis is common cause for
hypertension in young adults in Asian countries
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must keep in mind
Any questions?