DK2985_C000 1..28 - AlSharqia Echo Club

250 Transesophageal Echocardiography(A)(B)LIVERRAPERVLALVPE(C)LVOT FLOW(D)RVOT FLOWExpiration InspirationExpiration InspirationFigure 11.11 (A, B) Right atrial collapse in tamponade seen on TTE in a 53-year-old woman treated for a pericarditis. (C, D) Note thatthe right ventricular outflow tract (RVOT) Doppler velocities increase with inspiration as opposed to the left ventricular outflow tract(LVOT) velocities that decrease with spontaneous inspiration (LA, left atrium; LV, left ventricle; PE, pericardial effusion; RA, rightatrium; RV, right ventricle). (Courtesy of Drs. François Haddad and François Marcotte.)sensitive, IVC plethora is not a specific indicator of tamponadeas it only reflects elevated right atrial pressure.2. Doppler Features in Cardiac TamponadeWith normal physiology, small increases (,15%) in tricuspidand pulmonic peak flow velocities and right ventricularstroke volume and corresponding decreases (,10%)in left-sided parameters are seen during inspiration(Fig. 11.14). These respiratory variations are markedlyincreased in tamponade: both tricuspid and pulmonicvalve peak velocities nearly double with spontaneousinspiration, while both mitral and aortic valve velocitiesare decreased by .25% (5) (Fig. 11.14). The largestincrease in right-sided velocities and the largest fall inleft-sided velocities are observed on the first beat afterthe beginning of inspiration when cardiac tamponadeoccurs. Similar changes may be observed in patientswith significant chronic obstructive pulmonary disease(COPD) due to wide intrathoracic pressure changes, butin contradistinction, the changes in velocities are moregradual and the largest variation does not fall on the firstbeats of inspiration. Thus, a fall of .25% in the firstinspiratory mitral inflow E velocity compared with thefirst expiration E velocity in conjunction with a reciprocalexpiratory decrease of .25% in the late diastolic hepaticvenous flow velocity (or even diastolic flow reversal)[Fig. 11.15(A)] strongly suggests the presence of cardiactamponade. Tricuspid inflow signals show a reciprocalincrease in early E velocities from spontaneous expirationto inspiration.The diagnostic criteria of cardiac tamponade in patientsunder positive-pressure mechanical ventilation arereversed as the inspiratory changes described during spontaneousbreathing will be observed during the positivepressureexpiratory phase.In our experience, drainage of pericardial effusion inpatients under positive-pressure ventilation can be associatedwith deterioration of ventricular diastolic function(Fig. 11.15).3. Localized Chamber Compressionfrom HematomaLocalized PEs commonly occur after cardiac surgery, frequentlydue to localized bleeding and thrombus. Most