Extracellular Volume Detects Amyloidotic Cardiomyopathy and Correlates With Neurological Impairment in Transthyretin-familial Amyloidosis.
OBJECTIVE
Cardiac involvement determines prognosis and treatment options in transthyretin-familial amyloidosis. Cardiac magnetic resonance T1mapping techniques are useful to assess myocardial extracellular volume. This study hypothesized that myocardial extracellular volume allows identification of amyloidotic cardiomyopathy and correlates with the degree of neurological impairment in transthyretin-familial amyloidosis.


METHODS
A total of 31 transthyretin-familial amyloidosis patients (19 mean age, 49 ± 12 years; 26 with the Val30Met mutation) underwent a T1mapping cardiac magnetic resonance study and a neurological evaluation with Neuropathy Impairment Score of the Lower Limb score, Norfolk Quality of Life questionnaire, and Karnofsky index.


RESULTS
Five patients had cardiac amyloidosis (all confirmed by99mTc-DPD scintigraphy). Mean extracellular volume was increased in patients with cardiac amyloidosis (0.490 ± 0.131 vs 0.289 ± 0.035; P = .026). Extracellular volume correlated with age (R = 0.467; P = .008), N-terminal pro-B-type natriuretic peptide (RS= 0.846; P < .001), maximum wall thickness (R = 0.621; P < .001), left ventricular mass index (R = 0.685; P < .001), left ventricular ejection fraction (R = -0.378; P = .036), Neuropathy Impairment Score of the Lower Limb (RS= 0.604; P = .001), Norfolk Quality of Life questionnaire (RS= 0.529; P = .003) and Karnofsky index (RS= -0.517; P = .004). A cutoff value of extracellular volume of 0.357 was diagnostic of cardiac amyloidosis with 100% sensitivity and specificity (P < .001). Extracellular volume and N-terminal pro-B-type natriuretic peptide were the only cardiac parameters that significantly correlated with neurologic scores.


CONCLUSIONS
Extracellular volume quantification allows identification of cardiac amyloidosis and correlates with the degree of neurological impairment in transthyretin-familial amyloidosis. This noninvasive technique could be a useful tool for early diagnosis of cardiac amyloidosis and to track cardiac and extracardiac amyloid disease.
Servicio de Cardiología, Hospital Universitario Puerta de Hierro, Madrid, Spain.
María
M
Gallego-Delgado
Servicio de Cardiología, Hospital Universitario Puerta de Hierro, Madrid, Spain; Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain.
Esther
E
González-López
Servicio de Medicina Interna, Hospital Juan Ramón Jiménez, Huelva, Spain.
Francisco
F
Muñoz-Beamud
Servicio de Medicina Interna, Hospital Son Llàtzer, Palma de Mallorca, Spain.
Juan
J
Buades
Servicio de Neurología, Hospital Clínico San Carlos, Madrid, Spain.
Lucía
L
Galán
Servicio de Neurología, Hospital General Gregorio Marañón, Madrid, Spain.
Jose Luis
JL
Muñoz-Blanco
Philips Healthcare Iberia, Madrid, Spain; Unidad de Imagen Cardiaca Avanzada, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain.
Javier
J
Sánchez-González
Unidad de Imagen Cardiaca Avanzada, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain.
Borja
B
Ibáñez
Servicio de Cardiología, Hospital Universitario Puerta de Hierro, Madrid, Spain; Unidad de Imagen Cardiaca Avanzada, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain.
Jesus G
JG
Mirelis
Servicio de Cardiología, Hospital Universitario Puerta de Hierro, Madrid, Spain; Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain. Electronic address: JESUS.GMIRELIS@telefonica.net.
Pablo
P
García-Pavía
D000328:Adult; D000368:Aged; D028227:Amyloid Neuropathies, Familial / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D002306:Cardiac Volume / Q000502:physiology; D009202:Cardiomyopathies / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D009422:Nervous System Diseases / Q000150:complications* / Q000235:genetics; D015588:Observer Variation; D012307:Risk Factors
Amiloide; Amyloid; Cardiac magnetic resonance; Extracellular cardiac volume; Mapeo T(1); Resonancia magnética cardiaca; T(1)-mapping; Transthyretin; Transtiretina; Volumen cardiaco extracelular