Ross Murphy
Consultant Cardiologist, St James’ Hospital
Cardiac amyloidosis is a long-described disorder where a waxy, protein-like substance is deposited on the heart muscle making it stiff and, ultimately, weak.
Cardiac amyloidosis can cause breathlessness (labelled as ‘heart failure’) and heart rhythm problems that can lead to death. It has two main types: one is driven by proteins made by the bone marrow and the other by proteins made in the liver.
Stiff heart syndrome
Both reproduce the same, stiff heart that looks overgrown or too thick on cardiac ultrasound. It can cause neuropathy when protein is deposited in nerves. This leads to tingling in the arms and legs and, sometimes, loss of control on bowel and bladder function.
The bone marrow variety is essentially a type of low-grade cancer requiring chemotherapy to control it. The liver-driven process is often a genetic disorder.
Available treatment
Until the last two years, there was little available treatment, apart from a liver transplant that can sometimes be done if caught early enough. The liver version (TTR amyloid) can also occur in the elderly even if they don’t have the gene disorder or a family history of it.
Large-scale clinical studies published years ago suggest that the earlier the patient receives treatment, the better the long-term outcome.
Thankfully, there has been a sudden treatment breakthrough using a variety of novel technologies (including ‘gene-silencing’ drugs with possible long-term effects). Two new medications are now licenced in Ireland: a tablet-a-day and another involving intermittent infusion injections.
Helping families
We now have viable treatment to halt the deposition of these proteins. Large-scale clinical studies published years ago suggest that the earlier the patient receives treatment, the better the long-term outcome.
We must find affected families and pick up cases that are still early in development — to increase the amount of genetic testing and offer some hope for a disorder that, for so long, had no treatment.