Light-chain cardiac amyloidosis with neuropathy: a case report

Figures & data

Table 1 Electrophysiological features of the patient were comparable with typical length-dependent, predominantly axonal sensory-motor polyneuropathy

Nerve	MNCV (m/s)		CMAP (mV)		TL (ms)
	L	R	L	R	L	R
Peroneal	35.7	36.4	1.2	0.9	2.8	3.3
Tibial	36.0	36.7	2.9	3.7	5.2	5.1
Median	49.2	49.4	5.9	6.4	4.3	4.2
Ulnar	48.9	47.8	11.1	8.6	3.4	3.3
	SNCV (m/s)		SNAP (μV)		H-reflex (ms)
Median	41	39.7	11.4	10.9	34.7	32.9
Ulnar	44.4	42.9	8.4	8.1
Sural	19.6	22.3	3.2	2.9

Notes: Normal conduction velocities: median motor nerve ≥50.5 m/s; ulnar nerve ≥51.1 m/s; and sural nerve ≥32.1 m/s. Normal amplitudes: median motor nerve ≥6.0 mV; ulnar nerve ≥8.0 mV; and sural nerve ≥6.0 μV.

Abbreviations: MNCV, motor nerve conduction velocity; CMAP, compound muscle action potential; TL, terminal latency; L, left; R, right; SNCV, sensory nerve conduction velocity; SNAP, sensory nerve action potential.

Figure 1 Electrocardiogram revealed sinus rhythm, low voltages in limb leads, QS waves indicative of pseudoinfarction in precordial and inferior leads, first-degree atrioventricular block, and prolonged QTc.

Figure 2 A four-chamber apical view echocardiogram showing biatrial dilatation, valve thickening, thick ventricular walls (left ventricular wall is 15 mm and interventricular septum is 19 mm), and interventricular septum with speckled appearance, which suggests amyloid infiltrate.

Abbreviations: RV, right ventricle; LV, left ventricle; RA, right atrium; LA, left atrium.

Figure 3 Rectum biopsy: amyloid deposits are confirmed by a positive Congo red stain (arrow), which gives the characteristic salmon pink color (200×).