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Sports) or danger of trauma.

AORTIC STENOSIS

The diagnosis of AS is established by the characteristic

physical findings and two-dimensional and Doppler echocardiography.

The three most common etiologies are: 1)

rheumatic, 2) congenital, and 3) calcific or degenerative.

The majority of young adults with AS participating in

competitive athletics have congenital lesions.

Evaluation.Continuous-wave Doppler echocardiography

can reliably estimate the severity of AS, especially in the

presence of normal cardiac output, which is the case in the

great majority of those engaging in competitive sports (13).

Symptoms of dyspnea, syncope, or angina pectoris occur

late in the course of AS (14), and the likelihood of sudden

death increases significantly with the onset of symptoms.

Because even transient symptoms are so important in

marking the onset of increased risk of sudden death, the

physician must be aware that dyspnea, near-syncope, and

even syncope are likely to be unreported in competitive

athletes. Although sudden death is more frequent in symptomatic

patients with severe AS, it may also occur in

completely asymptomatic patients (15). When doubt persists

with regard to the severity of AS after Doppler study,

or if a patient with mild-to-moderate AS has symptoms,

cardiac catheterization should be performed. Sudden death

is rare with mild AS.

Athletes with a history of syncope, even with mild AS,

should be carefully evaluated by a cardiologist. This should

include assessment of arrhythmias with exercise. Syncope

should be regarded as a possible surrogate for spontaneously

aborted sudden death and should be thoroughly investigated

(see Task Force 7: Arrhythmias).

Severity of AS measured by continuous-wave Doppler

echocardiography (or in those instances previously noted by

cardiac catheterization) is categorized as follows with respect

to the calculated aortic valve area: mild _ greater than

1.5 cm2; moderate _ 1.0 to 1.5 cm2; and severe _ less than

or equal to 1.0 cm2 (5). This translates roughly (assuming

that athletes have normal cardiac output) to the estimated

mean aortic valve pressure gradient as follows: mild _ less

than 25 mm Hg; moderate _ 25 to 40 mm Hg; and severe _

greater than 40 mm Hg (5).

Because AS is often progressive, periodic re-evaluation at

least yearly is necessary and should be performed by a

physician with expertise in cardiology. This reassessment

includes physical examination and Doppler echocardiography,

but may require cardiac catheterization in selected

patients as previously noted. In addition, Holter monitoring

with intense exercise resembling competition is recommended

to detect ventricular arrhythmias in patients with

AS who wish to participate in competitive athletics.

In patients with AS, a markedly elevated cardiac output

or peripheral vascular resistance for sustained periods of

time could result in an exaggerated valvular gradient and a

marked increase in LV systolic pressure. Given these precautions,



the following recommendations can be made.

Recommendations:


Date: 2016-03-03; view: 729


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