Respiratory Variations of Doppler Echocardiographic Parameters in Cardiac Tamponade

BACKGROUND: Cardiac tamponade is associated with the expiratory increase and the expira-tory decrease in left ventricular filling flow. With Doppler echocardiography, we analyzed the respiratory variations of mitral and tricuspid inflows, and pulmonary and hepatic venous flows in patients with cardiac tamponade. METHODS: Respiratory hemodynamic changes in mitral and tricuspid inflows and pulmonary and hepatic venous flows were evaluated using Doppler echocardiography in 13 patients (6 men and 7 women; mean age 51+/-13 years) with large pericardial effusion and clinical cardiac tamponade, and compared the results with those of 11 control subjects (3 men and 8 women, mean age 53+/-13 years). Doppler examination was repeated after pericardiocentesis in 6 patients. RESULTS: Peak velocity of early diastolic mitral inflow (E velocity) decreased during inspiration compared with expiratory increase; the mean percentage change was 40%. Peak velocity of late diastolic mitral inflow (A velocity) decreased 13% during inspiration. E/A ratio decreased 31% during inspiration. Deceleration time (DT) and isovolumic relaxation time (IVRT) increased by 26% and 44%, respectively, during inspiration. But respiratory variations of tricuspid inflow were opposite to those of mitral inflow. Tricuspid E velocity increased during inspiration and decre-ased during expiration. The mean percentage change was 123%, which was larger than thte 40% of mitral inflow. The most characteristic findings of pulmonary venous flow during respiration were the expiratory increases of peak diastolic velocity (DV) and diastolic time-velocity integral (D-TVI). The mean percentage changes of peak systolic velocity (SV), DV and D-TVI during respiration were 27%, 45% and 53% respectively. In contrast, the SV and DV of hepatic venous flow increased during inspiration and decreased during expiration. The respiratory variations of peak systolic reverse flow velocity (SR) and peak diastolic reverse flow velocity (DR) were opposite to those of SV and DV. DR notably increased during expiration, and the mean percentage change was 61%. The ratio of RFI (Inspiratory reverse flow integral) to FFI (forward flow integral) of the tamponade group was 270%. The mean percentage changes of each parameters decreased after pericardiocentesis. CONCLUSION: Patients with cardiac tamponade showed inspiratory increases of diastolic tri-cuspid filling flow and hepatic forward flow. Expiratory increases included diastolic mitral filling flow, pulmonary venous systolic and diastolic flow, and hepatic venous reverse flow. Such res-piratory variations decreased after pericardiocentesis.

Assessment of Left Atrial Appendage Flow Pattern Using Multiplane Transesophageal Echocardiography in Patients with Nonrheumatic Atrial Fibrillation and Ischemic Stroke

BACKGROUND: The efficacy of oral anticoagulant therapy in reducing the risk of stroke and systemic embolism has been demonstrated in patients with nonrheumatic atrial fibrillation, but anticoagulation may introduce the risk for serious complications or adversely affect the patient's usual activities. Because the left atrial appendage(LAA) is the most likely site of thrombus formation in patients with nonrheumatic atrial fibrillation, evaluation of the LAA function with transesophageal echocardiography(TEE) may be helpful to deterrnine the high risk group for ischemic stroke. METHODS: Twenty patients with nonrheumatic atrial fibrillation(group I ), eighteen patients with rheumatic atrial fibillation(group II ) and twenty subjects in normal sinus rhythm without valvular heart disease(group III ) were underwent multiplane TEE examination. We measured maximal and minimal areas, ejection-fraction, and peak contraction and relaxation velocities of LAA. We also observed the presence or absence of thrombus and spontaneous echo contrast (SEC) in the left atrium or LAA. RESULTS: Maximal area of LAA was larger in group I and II compared with group III but there was no difference between group I and group II. Ejection fraction of LAA was much decreased in group I and II compared with group III. Peak contraction and relaxation velocities of LAA were over 45cm/sec in all cases from group Ill, but there was nearly negligible flow measurable in cases from group II. Patients from group I showed two distinct LAA flow patterns, either well defined saw tooth flow pattem(9 cases) or very low flow pattern like that of group II (11 cases). Therefore, patients from group I could be divided into two subgroups according to LAA flow profile. High flow profile subgroup had clear saw tooth flow pattern and revealed over 20cm/sec of peak contraction and relaxation velocities. The other low flow profile subgroup showed under 20cm/sec of both velocities. LAA ejection fraction was more increased in high flow profile subgroup but not significantly. Ischemic stroke occurred in six patients from group I, and all were in the low flow profile subgroup(p<0.05). SEC was observed in eight cases(73%) of the low flow profile subgroup but in only one case(11%) of the high profile sbugroup(p<0.05). All three cases with LAA thrombus belonged to the low flow profile subgroup. CONCLUSIONS: The assessrnent of LAA function by TEE may be helpful to discriminate the high risk group for the potential ischemic stroke in patients with nonrheumatic atrial firillation.