'Here comes the story of the Hurricane': a case report of AL cardiac amyloidosis and myocardial bridging

Abstract

Background: Cardiac amyloidosis (CA) is a rapidly progressive infiltrative cardiomyopathy, whose role is emerging as a not-so-rare disorder leading to heart failure (HF). Myocardial bridge (MB) is the most common inborn coronary artery variant, and its clinical relevance is still matter of debate. The exceptional coexistence of these two conditions could accelerate disease progression and worsen the already compromised clinical conditions.

Case summary: We present the case of a 76-year-old female patient experiencing relapsing HF decompensation and presenting to our centre with dyspnoea at rest and severe peripheral congestion. Echocardiogram showed severe concentric hypertrophy, severe biventricular contractile dysfunction, and third-degree diastolic dysfunction. Coronary angiography excluded epicardial atherosclerotic disease, though displaying a long intramyocardial course of left anterior descending artery. Physiological invasive test was achieved in terms of instantaneous wave-free ratio (iFR), both at baseline and after inotropic and chronotropic stimuli, and attested haemodynamic significance. Concurrently, the diagnostic flow chart for CA was accomplished, by means of both invasive (periumbilical fat biopsy, bone marrow aspiration) and non-invasive tests (99mTc-diphosphonate scintigraphy, serum-urine immunofixation) that confirmed the suspect of primary amyloidosis. Acute HF therapy was personalized according to the singularity of the case, avoiding both nitrates and beta-blockers, then first cycle of chemotherapy was started.

Discussion: Our clinical case shows a unique interaction between infiltrative cardiomyopathy and coronary artery abnormality. Amyloidosis can contribute to the ischaemic burden of the MB and this may, in turn, abbreviate the path to HF decompensation.

Keywords: Cardiac amyloidosis; Case report; Functional intracoronary assessment; Heart failure; Myocardial bridge.

© The Author(s) 2022. Published by Oxford University Press on behalf of the European Society of Cardiology.

Figures

Figure 1

The electrocardiogram shows sinus rhythm, first-degree atrioventricular block, Q waves, and no R-wave progression (pseudo-infarction pattern) in pre-cordial leads.

Figure 2

(A and C) Steady-state free precession cine images acquired in diastolic phase show an asymmetric hypertrophic phenotype (short axis and horizontal long axis, respectively). Black arrowheads highlight a prevalent hypertrophy of mid-basal septal segments and basal inferior wall of right ventricle. Inter-atrial septum (black asterisk) and biatrial wall (black arrows) shows regular thickness. (B) Boundary points representation of cardiac magnetic resonance tissue tracking analysis (Circle, cvi42, Calgary, Canada; version 5.11.4): epicardial and subendocardial deformability, respectively, represented by external and internal lines and dots. Short-axis systolic acquisition: septal segments clearly show the lower deformability (white arrowheads). (D) Colour map representation of cardiac magnetic resonance tissue tracking analysis: darker blue colours represent a higher myocardial deformation; lighter blue and yellow-to-red colours represent a lower deformation. Apical segments show regular deformability (‘apical-sparing pattern’). Overall systolic function was moderately depressed.

Figure 3

Two-dimensional myocardial delayed enhancement sequences acquired in systolic phase in both short-axis (A–C) and horizontal long-axis planes (D). (AC) The same short-axis 2D myocardial delayed enhancement slice acquired with different inversion time. Diffuse subendocardial enhancement (white arrowhead) is highlighted in basal segments with transmural involvement in mid-basal inferior segments (white asterisk). Marked enhancement is highlighted also in right ventricle and atrial wall (white arrows). Diffuse subendocardial late gadolinium enhancement pattern is typically present in patients with cardiac amyloidosis.

Figure 4

Transthoracic echocardiography showing severe concentric hypertrophy. Two-dimensional four-chamber apical view of the left ventricular showing severe hypertrophy, with an inter ventricular septum (IVS) of 18.5 mm.

Figure 5

Transthoracic echocardiography evaluating diastolic function. (A) Pulsedwave Doppler with the sample volume at the left ventricular inflow (mitral valve leaflet tip) revealing a third-degree diastolic dysfunction (restrictive pattern). (B) Tissue Doppler imaging of the left ventricular confirming very high left ventricular filling pressure.

Figure 6

Coronary angiography revealing a long left anterior descending myocardial bridge. (A) Left cranial projection in diastole; (B) left cranial projection in systole; (C) right projection in diastole; (D) right projection in systole. White arrows indicate the tract of myocardial bridge with a long and severe systolic narrowing (‘milking’) of the proximal/mid-left anterior descending epicardial artery.