Delayed hyper-enhancement magnetic resonance imaging provides incremental diagnostic and prognostic utility in suspected cardiac amyloidosis.
OBJECTIVE
We sought to assess the diagnostic accuracy and incremental prognostic value of delayed hyper-enhancement cardiac magnetic resonance (DHE-CMR) compared with electrocardiographic and transthoracic echocardiographic (TTE) parameters in such patients.


BACKGROUND
Utility of DHE-CMR in the diagnosis of patients with suspected cardiac amyloidosis (CA) has recently been demonstrated, but its incremental prognostic utility is unclear.


METHODS
Forty-seven consecutive patients (mean age 63 years, 70% men, 55% New York Heart Association functional class >II) with suspected CA who underwent electrocardiography (ECG), TTE, DHE-CMR, and biopsy (38 endomyocardial, 9 extracardiac) were studied. Low voltage on ECG was defined as S-wave in lead V(1) + R-wave in lead V(5) or V(6) <15 mm. TTE parameters, including deceleration time, E/E' ratio, and diastolic grade were recorded. CMR was considered positive with diffuse DHE of the subendocardium extending to adjacent myocardium. All-cause mortality was ascertained.


RESULTS
In the study population, 59% had low voltage on ECG, 30% had abnormal deceleration time < OR = 150 ms, 38% had E/E' ratio >15, and 47% had advanced (pseudonormal or restrictive) diastology.The diagnostic accuracy of DHE-CMR in patients undergoing endomyocardial biopsy was as follows: sensitivity 88%, specificity 90%, positive predictive value 88%, and negative predictive value 90%. On multivariable logistic regression testing of the diagnostic ability of various noninvasive imaging parameters, only DHE-CMR was significant (Wald chi-square statistic 9.6, p < 0.01). At 1-year post-biopsy, there were 9 (19%) deaths. On Cox proportional hazards analysis, only positive DHE-CMR was a predictor of 1-year mortality (Wald chi-square statistic 4.91, p = 0.03).


CONCLUSIONS
A characteristic DHE-CMR pattern is more accurate for diagnosis and is a stronger predictor of 1-year mortality in patients with suspected CA as compared with other noninvasive parameters.
Austin
Bethany A
BA
Tang
W H Wilson
WH
Rodriguez
E Rene
ER
Tan
Carmela
C
Flamm
Scott D
SD
Taylor
David O
DO
Starling
Randall C
RC
Desai
Milind Y
MY
D000368:Aged; D000686:Amyloidosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology; D001706:Biopsy; D003287:Contrast Media; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013997:Time Factors
D003287:Contrast Media