Septal bounce in a lupus patient
Here is a subcostal view of the heart obtained from a young lupus patient presenting with symptoms of new onset heart failure. Nephrologists may encounter this type of presentation in the clinic.
Findings: LV systolic function appears to be OK and there is some pericardial effusion. The pericardium appears unusually thickened. Also note the ‘bouncy septum’ (= ventricular septal motion abnormality) – suggestive of constrictive pericarditis. It means initial septal movement towards and then away from the left ventricle during early diastole.
Pathophysiology: Inspiration reduces intrathoracic pressure which usually is fully transmitted to intracardiac pressures. In constriction, the intracardiac pressures fall much less than intrathoracic pressure because of pericardial constraint. This difference in pressure change with inspiration results in reduced filling to left side of the heart. The reduction in left heart filling during inspiration causes a reduction in mitral inflow velocity and a shift of the interventricular septum toward the LV. With expiration, left heart filling increases which shifts the septum back toward the RV, leading to reduced filling to right side of the heart and a late-diastolic reversal of flow in the hepatic veins.
Doppler imaging helps better to assess these flow abnormalities but for the purpose of limited echo, its’ OK as long as you identify septal bounce and seek cardiology consultation for a formal echo. The effusion is not always present.
Case courtesy: Dr. Robert Jones
Sometimes, the bounce is not clear on eyeballing. M-mode can be of help in such situations. Can do both in PLAX and PSAX views below the mitral valve leaflets. Here is an example:
Below are two more examples of constrictive pericarditis shared by Drs. Omid Kiamanesh and Kazi Ferdous. Note the septal bounce, thickened pericardium and a small pericardial effusion (asterisk in first image) in apical 4 chamber view. Also, if you carefully observe, medial mitral valve annulus (one by the septum) moves more than the lateral annulus, because lateral annular motion is restricted by the thickened pericardium -> distinguishing feature from cardiomyopathy where medial annulus also doesn’t move much. Serum BNP level is typically low in these cases because the pericardial constraint prevents ventricles from stretching (& making BNP in response).