Life-saving implantable cardioverter defibrillator therapy in cardiac AL amyloidosis

Abstract

Cardiac involvement is the main determinant of prognosis in systemic monoclonal immunoglobulin light chain (AL) amyloidosis. Ventricular arrhythmias and sudden cardiac death are not uncommon. The electrical events that precede sudden death, and their potential to be treated effectively, remain undefined. There are no European guidelines for the use of implantable cardioverter defibrillator (ICD) in amyloidosis. ICDs in general are not usually offered to patients with a life expectancy of less than 1 year. We describe a patient who presented with cardiac AL amyloidosis who underwent prophylactic ICD implantation for the prevention of sudden cardiac death during treatment with chemotherapy, in whom life-threatening ventricular arrhythmia was successfully terminated over a 3-year period.

Figure 1

Twelve lead ECG demonstrating sinus rhythm with normal PR interval and QRS duration, poor R wave progression in chest leads, with Q waves in I and aVL and diffuse repolarisation abnormalities. QRS complexes are of a normal amplitude.

Figure 2

Top: diastolic frame cines of three long-axis views showing moderate left ventricular hypertrophy of the left ventricle. Note this is predominantly at the level of the interventricular septum. Bottom: late gadolinium enhancement (LGE) images in the same planes with phase sensitive inversion recovery reconstruction. There is evidence of LGE which is more pronounced at the level of the subendocardium that becomes transmural in many areas. The blood pool is dark, which does not frequently occur in other conditions.

Figure 3

First implantable cardioverter defibrillator therapy: atrial (A) and ventricular (V) electrograms (EGM; top), farfield EGM, and channel marker (bottom) demonstrating ventricular tachycardia (ventricular rate>atrial rate, cycle length 245–255 detected in the ventricular fibrillation (VF) zone) onset after PVC (premature ventricular contraction) (not shown), treated with short burst antitachycardia pacing (8 beats) followed by VF appropriately detected and terminated (41 J shock).

Figure 4

Implantable cardioverter defibrillator therapy more than 2 years following implantation: atrial and ventricular electrograms (EGM; top), farfield EGM, and channel marker (bottom) demonstrating ventricular tachycardia or ventricular flutter (cycle length 255–280 detected in the ventricular fibrillation (VF) zone) onset after PVC (not shown), treated with short burst antitachycardia pacing (8 beats) followed by VF appropriately detected and terminated (41 J shock).