Electrocardiographically Discrete Tamponade

Report:

Sinus rhythm.

Normal axis

Left atrial abnormality

Left ventricular hypertrophy with ST/T changes

Comment:

On reflection, not two, but three things are missing: tachycardia, signs of pericardial involvement (pericarditis) and small voltage. Electrical alternans is not common enough to be actually expected.

The patient was in extremis without tachycardia: the chronotropic incompetence in this situation is not associated with survival. This case was no exception.

The epicardial involvement, i.e., signs of pericarditis, are often missing in malignant effusions161; the fluid may accumulate due to lymphatic blockage and the cellular infiltrate may not provoke an inflammatory response. It is often forgotten that the pericardium is, by itself, electrically silent: any observable pericarditis is, in reality, an epicarditis.

Voltage loss is common in all forms of pericardial disease (even "dry" pericarditis), perhaps due to the loss of the electrical dipole between different parts of pericardial surface. With LVH, on the other hand, both voltage loss and the ST/T changes of pericarditis may be masked. This commonly obtains with uræmic pericarditis.

Note the preserved septal q wave in V6, distinguishing the LVH from incomplete LBBB.