Final The Echo Manual DIGITAL
Chapter 12 Pericardial Diseases
CHAPTER 12 PERICARDIAL DISEASES
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replacement and constrictive pericarditis, the e ′ veloc- ity may not be increased because of annular tethering by the prosthesis (Fig. 12-26). In both these situations, the mitral inflow should still show respiratory varia- tion, with exaggerated expiratory diastolic flow rever- sal on the hepatic vein Doppler recording. The mitral prosthesis inflow deceleration time should be shorter than expected due to elevated LV diastolic pressure (Fig. 12-26). 4. With mixed constriction and restrictive myocardial disease due to radiation or cardiac surgery, the medial mitral annulus e ′ may be less than 9 cm/s, and annulus paradoxus may not exist. Phasic respiratory changes in ventricular septal motion, mitral inflow E velocity, and the hepatic vein Doppler profile must be seen to identify constriction. 5. Atrial fibrillation makes the interpretation of respi- ratory variation in Doppler velocities difficult, as these velocities are also influenced by the irregular R-R intervals. Despite this fact, respirophasic varia- tion can sometimes be discerned on long Doppler
mitral inflow velocity usually occurs during inspira- tion. It is important to instruct the patient to breathe smoothly during the Doppler recording because an erratic breathing pattern distorts the timing of Doppler flow velocities. The direction of the respirometer trac- ing, which indicates inspiration versus expiration, may be reversed (i.e., upward deflection for expiration and downward for inspiration) in certain echocardiogra- phy instruments (Fig. 12-25A). 2. The hepatic vein expiratory diastolic flow reversal is the most specific Doppler echocardiographic finding for constriction (26). As these velocities are of low amplitude, the pulsed wave Doppler filter should be set low, as should the velocity scale, to adequately display this characteristic flow profile of constriction (Fig. 12-25B). 3. The mitral e ′ velocity is reduced when adjacent myo- cardium is diseased. With coexisting inferior wall myocardial infarction, the septal e ′ velocity may be less than 7 cm/s even if the patient has constrictive pericarditis. Likewise, in patients with mitral valve
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FIGURE 12-25 A: Hepatic vein pulsed wave Doppler velocity recording with a simultaneous respirometer recording. In this case, upward respirometer recording indicates expiration ( upward arrow ) since forward flow velocity is reduced. Downward arrow indicates diastolic flow reversal with expiration. B: Two separate hepatic Doppler recordings from the same patient with con- strictive pericarditis. A lower velocity scale on left is more desired since the diastolic flow reversal ( arrow ) velocity appears more prominent compared to the recording with a higher velocity scale ( right ).
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