Amyloidosis, Cardiologist Carigi: "Protein Buildups Alter Heart Function"

"Even small deposits of amyloid in the heart lead to alterations in its function, especially the diastolic function, that is, the filling function. Only in the most advanced phase of the disease is the systolic function, the emptying function, also affected. Cardiac involvement is the one that has the greatest impact on the prognosis of patients". This was stated by Samuela Carigi, cardiologist in charge of the Heart Failure and Cardiomyopathy Outpatient Clinic at the Infermi Hospital in Rimini of the Romagna Local Health Authority, speaking at the press conference 'Cardiac amyloidosis: when the heart hides a rare disease', which was held today in Milan at the headquarters of Bayer Italia.

"Cardiac amyloidosis - explains the expert - can be due to different proteins that, by breaking down, cause the formation of amyloid fibrils that are deposited in the extracellular spaces of various organs and tissues. The most common forms are Al, from an alteration of a clone produced by the bone marrow, and Attr, from the breakdown of transthyretin, a protein produced mainly by the liver. Amyloid fibrils are deposited in various tissues, one of the main ones, especially in the transthyretin form, is the heart. It is not well known why amyloidosis particularly favours the cardiac muscle. It is assumed that the mechanisms are different, including the fact that the heart is a moving organ. The oxidative stress it produces in the systolic-diastolic phase is, therefore, considerable and this can favour the instability of circulating proteins. It is, moreover, a highly vascularised organ, therefore exposed to high levels of circulating proteins. The fibrils of amyloid binds to the cardiac extracellular matrix, which is composed mainly of collagen but also of proteoglycans, and the mechanisms for removing this matrix in the heart are limited. It is probably for a combination of these reasons that the heart is a target organ".

The patient who presents to the expert "may have a picture of heart failure - the cardiologist highlights - More frequently he has preserved ejection fraction, shortness of breath and dyspnea, as well as arrhythmias. In amyloidosis, in fact, atrial fibrillation can frequently develop. There may also be the presence of hypotension, that is, a reduction in blood pressure values".

An important 'red flag', an alarm bell that should not be underestimated, is "when the general practitioner finds himself having to reduce or suspend antihypertensive therapy for a patient, especially in the elderly segment of the population, who has been hypertensive for several years - warns Carigi - The same happens if the patient reports chest pain, a rarer eventuality that can be associated with what could be called angina, even if in reality it is linked to the interaction of the microcirculation that accompanies amyloidosis".

Precisely for this reason "the creation of a multidisciplinary team in amyloidosis is fundamental, more than in other cardiac pathologies, both to speed up the diagnosis and to define the final diagnosis, because there are different types of pathology - explains the specialist - Multiorgan involvement requires, for example, the need to undergo a six-monthly neurological examination, in addition to the cardiological examination, rarely, in hereditary forms, the ophthalmological examination or the gastroenterological examination. We must therefore have specialists who are dedicated and trained in the management of this type of patient and who work in a network".

Amyloidosis therapy "can be expressed at 3 fundamental levels - explains the specialist - The first is the reduction of synthesis, the second consists, as regards Attr amyloidosis, in the stabilization of the transthyretin tetramer, so that it does not break down, and the third level, which will arrive in the future, will be the removal of amyloid from the tissues. We have molecules that act on the reduction of hepatic synthesis of transthyretin and are currently used in patients with amyloidotic polyneuropathy. It is already possible - she concludes - to stabilize the tetramer, with molecules called tetramer stabilizers that prevent its breaking down and therefore the further accumulation of amyloid in the tissues".