Online
Clinical Case Study (September 2005)
Clinical
Cardiology Series
臨床心臟科個案研究
The
content of the Office Cardiology Series is provided by:
Dr. Li Siu Lung, Steven
M.B.,B.S.(H.K.),M.R.C.P.(U.K.),F.H.K.A.M.,F.H.K.C.P.,F.R.C.P.(Glasg.),F.R.C.P.
(Edin.),Specialist in Cardiology
Dr. Wong Shou Pang, Alexander
F.R.C.P.,F.H.K.A.M.(Med.),F.H.K.C.P.,Specialist in Cardiology
臨床心臟科個案研究之內容誠蒙李少隆醫生及王壽鵬醫生提供。
A 65 year old man
with good past health presents to your office with recent palpitation attacks.
He experiences a mild decrease in exercise tolerance, although there is no symptom
of congestive heart failure. Physical examination reveals no cardiac murmur
and his blood pressure is normal. ECG shows atrial fibrillation.
Answers
| 1. |
Is
cardioversion indicated for him?
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Class I indications
for cardioversion include emergency cardioversion of any arrhythmia resulting
in hemodynamic instability, myocardial ischemia, congestive heart failure
or symptomatic intolerance. Elective cardioversion for stable atrial fibrillation
is usually a class II indication. However, it is usually recommended if
the atrial fibrillation is less than 1 year’s duration or if it is associated
with embolic episodes or decreased exercise tolerance. A long duration
of atrial fibrillation and a large atrial size by echocardiogram predict
a lower success rate and a higher recurrence rate.
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| 2. |
How
should you prepare the patient for cardioversion?
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In atrial
fibrillation of more than 48 hours or uncertain duration, four weeks of
anticoagulation before the procedure is recommended. If earlier cardioversion
is desired, the patient may be put on intravenous heparin for two days
before with transesophageal echocardiography to rule out any intra-atrial
thrombus. After cardioversion, another four weeks of anticoagulation is
recommended.
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| 3. |
What
should be the technique of cardioversion?
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On the day
of procedure, the patient should be kept fasting for 6 to 8 hours prior
to the procedure. An intravenous short-acting agent such as midazolam
is used for sedation and amnesia. For elective cases, the anteroposterior
electrode positions are the most effective. Synchronization must be used.
The initial energy may be 100-200J, followed by 300-360J on subsequent
attempts.
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| 4. |
What
are the risks of cardioversion?
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In general,
cardioversion for atrial fibrillation is safe and effective. The potential
complications include:
a. Respiratory
compromise and/or aspiration
b. Embolization
Prophylactic
temporary pacemaker placement may be needed for patients with sick sinus
syndrome or severe conduction system disease.
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Dermatology
Series 皮膚科病例研究
An 8 year old otherwise
healthy boy presented with multiple skin papules over his upper limb for three
months. The skin lesions were asymptomatic, except for occasional itch and mild
pain. His elder brother also got similar skin lesions. Physical examination
revealed multiple 2-4 mm size papules over his forearm, some appeared as pearly.
Central depression was seen in some lesion. Some lesions appeared to be arranged
in a line.
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The
content of the Dermatology Series is provided by:
Dr. Chan Loi Yuen and Dr. Tang Yuk Ming, William
Specialist in Dermatology & Venereology
皮膚科病例研究之內容誠蒙陳來源醫生及鄧旭明醫生提供。 |
Answers
| 1. |
What
is the clinical diagnosis?
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The diagnosis
is molluscum contagiosum (MC).
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| 2. |
What
is the natural course of the disease?
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MC is caused
by molluscum contagiosum virus, which is a pox virus. It is very common
in childhood. The characteristic feature is crops of dome-shaped, umbilicated,
flesh-coloured papules. Curd-like material can be extracted from the lesion.
Without treatment, it may persist for six months to two years although
some case may last for longer. The lesion may be complicated by infection.
Transmission is by skin-to-skin contact, including auto-inoculation and
sexual contact.
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| 3. |
What
is Koebner phenomenon?
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Koebner phenomenon,
also known as isomorphic phenomenon, describes the occurrence of skin
lesions along a scratch line. Common conditions that exhibit such phenomenon
include psoriasis, warts, molluscum contagiosum, lichen planus and herpes
simplex.
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| 4. |
How
would you confirm the diagnosis?
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The diagnosis
of MC is usually made clinically. Atypical cases may be confused with
naevi, warts, basal cell carcinoma. Histology will reveal the characteristic
intracytoplasmic inclusion bodies.
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| 5. |
What
are the treatments?
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The condition
is usually self-limiting. Enlarging or spreading lesions may be treated.
Gentle manual expression of the central core by pricking with a sterile
needle is simple and effective. Individual lesion may also be removed
by curettage or cryotherapy. Other treatment options include topical tretinoin,
imiquimod, silver nitrate and trichloroacetic acid.
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