The most common cause of failure of the right side of the heart is left ventricular failure. Pulmonary hypertension offers resistance to the pumping action of the right side and it too begins to fail. Once again there is a backlog of blood, but this time into the systemic venous circulation (systemic venous hypertension). This leads to oedema in a number of organs, but that in the lower limbs (peripheral oedema) is most obvious since it is manifest as swollen ankles, which pit when gently pressed with the pads of the fingers.
When left and right ventricular failure occur together, the term congestive cardiac failure is used since pulmonary venous and systemic venous congestion occur.
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