The Association of Atrial Tachyarrhythmias with Isolated Atrial Amyloid Disease: Preliminary Observations in Autopsied Heart Specimens

Abstract

Objective: Isolated atrial amyloidosis (IAA) is associated with atrial tachyarrhythmias. However, only a few studies have appraised atrial tachyarrhythmias and atrial depolarization abnormalities in connection with high-grade IAA. We conducted a collaborative retrospective study to assess this association. Methods: One hundred consecutive autopsied hearts were studied histologically for IAA. To increase the specificity for atrial depolarization abnormalities in this preliminary study, we excluded those specimens with intermediate amyloid involvement, i.e. IAA grades 1 and 2 (grade 0 = absent or trivial deposits; grade 1 = small deposits; grade 2 = moderate deposits; grade 3 = dense, large deposits). We then screened for baseline, premortem electrocardiograms (ECGs) to assess rhythm. In those with sinus rhythm, the P wave axis, duration, dispersion and terminal force in V1 were determined under magnification. Results: Of the 27 premortem ECGs corresponding to the autopsy specimens with grades 3 (sample) or 0 (controls) IAA, 9 showed sinus rhythm, 13 showed atrial fibrillation, 1 showed atrial flutter and 4 were uninterpretable. Fourteen autopsied hearts (52%) were positive for grade 3 IAA. Ten of those had atrial tachyarrhythmias (9 atrial fibrillation and 1 atrial flutter) compared to 4 of the 13 hearts with grade 0 IAA (72 vs. 31%, respectively; p = 0.03). Although there was excellent interobserver agreement using intraclass correlation coefficients, there were no significant differences in P wave measurements among the small number of patients with sinus rhythm for grade 3 versus grade 0 IAA. Conclusion: In a collaborative, preliminary, pilot assessment of autopsied hearts for which premortem ECGs were necessarily screened retrospectively, significantly more hearts with high-grade IAA were associated with atrial tachyarrhythmias compared to those with low-grade IAA. A larger study with an appropriately matched autopsy control group is needed to confirm these and previous observations.

Updates in Cardiac Amyloidosis: A Review

“…Localized atrial amyloid deposits derived from atrial natriuretic peptide are associated with atrial fibrillation, notably postoperatively, and become ubiquitous with age, being present at autopsy in 80% of people >70 years of age . The significance and causality of atrial natriuretic peptide amyloid deposits remain unknown.…”

“…Although the echocardiographic manifestations of cardiac ATTR may be indistinguishable from advanced AL amyloidosis, patients with the former typically have fewer symptoms and better survival. 37 Other Types of Cardiac Amyloidosis Localized atrial amyloid deposits derived from atrial natriuretic peptide are associated with atrial fibrillation, notably postoperatively, 9,38 and become ubiquitous with age, being present at autopsy in 80% of people >70 years of age. 39,40 The significance and causality of atrial natriuretic peptide amyloid deposits remain unknown.…”

Diagnostic approach to light-chain cardiac amyloidosis and its differential diagnosis

“…The classical presentation of AL cardiomyopathy is a rapid progression of symptoms of diastolic heart failure, which may result in many serious heart consequences such as arrhythmias, syncope, ischemic heart disease, and intracardiac thrombus formation. Atrial fibrillation is seen in 9% of patients [11].…”

Širdies Magnetinio Rezonanso Tomografijos Reikšmė Širdies Amiloidozės Diagnostikoje

“…Pagal etiologiją amiloidozė skirstoma į pirminę, antrinę, šeiminę ir senatvinę. Širdies miokardą pažeidžiantys tipai yra AL amiloidozė, kai kurios įgimtos arba paveldimos amiloidozės formos (ATTR, AApoA-I), SSA ("Wild tipe" TTR amiloidozė), izoliuota prieširdžių amiloidozė ir antrinė amiloidozė [6,9,[18][19][20][21][22][23][24][25]. Dažniausios amiloidozės formos, pažeidžiančios širdį, apibūdintos ir apibendrintos 3 lentelėje priede.…”