The development of cardiac tamponade depends more on the rate of pericardial fluid accumulation and pericardial compliance than on the absolute size of the effusion. With an acute pericardial effusion, the pericardium has not had time to stretch, so even 50 mL of rapidly accumulating fluid may produce tamponade physiology. In contrast, a chronic pericardial effusion allows the pericardium to gradually increase its compliance, permitting up to 2 liters of fluid to accumulate b

Tricuspid annular plane systolic excursion (TAPSE) is a simple, reproducible quantitative measure of longitudinal right ventricular (RV) systolic function. In the RV-focused apical 4-chamber view, TAPSE is measured using M-mode as the vertical displacement of the lateral tricuspid annulus from end-diastole to end-systole. Because the RV's deep subendocardial fibers are oriented longitudinally, this motion accounts for approximately 80% of RV stroke volume. Greater systolic de

Within the aortic lumen, a dissection flap appears as a long, hyperechoic, undulating structure extending from one wall of the aorta to the other, separating the true and false lumens. Unlike indirect findings such as a dilated aortic root, aortic regurgitation, or pericardial effusion, a dissection flap is a direct sonographic sign of acute type A aortic dissection. Recognizing this finding should prompt immediate diagnostic confirmation and definitive management in the appr

A normal or non-diagnostic ECG does not exclude acute coronary occlusion. In patients with a concerning history and physical examination, bedside echocardiography can identify regional wall motion abnormalities (RWMAs) that may be present before ECG changes or biomarker elevation. In this patient with chest pain, notice how the left ventricular posterior wall (perfused by the right coronary artery) is akinetic, whereas the septal wall (perfused by the left anterior descending

A pericardial effusion should be classified according to its hemodynamic impact, size, distribution, onset, and composition. Each of these characteristics provides important diagnostic and management information. For example, a small, rapidly accumulating effusion may produce cardiac tamponade physiology, whereas a large chronic effusion may be well tolerated with little or no hemodynamic compromise. A systematic approach ensures that bedside echocardiography moves beyond sim