Volume 13 Supplement 1

Abstracts of the 2011 SCMR/Euro CMR Joint Scientific Sessions

Open Access

Impact of cardiovascular magnetic resonance assessment of ejection fraction on eligibility for implantable cardioverter defibrillators

  • Subodh B Joshi1,
  • Kim A Connelly1,
  • Mark Hansen2,
  • Sean McSweeney1,
  • Jerome Liu1,
  • Yuesong Yang2,
  • Laura Jimenez-Juan3,
  • Abdul Al-Hesayen1,
  • Iqwal Mangat1,
  • Paul Dorian1,
  • Graham A Wright2,
  • Andrew Crean3,
  • Anish Kirpalani1,
  • Andrew T Yan1 and
  • Howard Leong-Poi1
Journal of Cardiovascular Magnetic Resonance201113(Suppl 1):O32

DOI: 10.1186/1532-429X-13-S1-O32

Published: 2 February 2011

Objective

To determine whether cardiovascular magnetic resonance (CMR) for left ventricular ejection fraction (LVEF) assessment changes implantable cardioverter defibrillator (ICD) eligibility when compared with echocardiography.

Background

A markedly reduced LVEF is considered an indication for ICD placement for the primary prevention of sudden cardiac death. However, despite strict LVEF criteria, most guidelines do not specify the technique by which LVEF should be measured.

Methods

The study population consisted of patients referred for LVEF measurement by CMR, for consideration of ICD implantation, who also underwent echocardiography within 30 days of the CMR. LVEF was assessed on echocardiography using Simpson’s biplane method. LVEF was determined from CMR based on manual planimetry of SSFP cine images of contiguous left ventricular short axis slices. CMR and echocardiography derived LVEFs were reported by two independent blinded observers.

Results

Forty-nine (49) eligible patients were identified (10 female, mean age 61 +/- 15 years, 24 with ischemic etiology) who underwent CMR between March 20, 2007 and Aug 12, 2010. The median number of days between CMR and echo was 3 (IQR 1 to 10 days). The mean LVEF by CMR and echo was 31 +/- 15 %, and 34 +/- 15%, respectively, (p =0.009), with a correlation coefficient (r) between the two of 0.86. Using Bland Altman analysis, the mean difference (CMR - echo) was - 3.1 % with limits of agreement of - 18 to 12 %. CMR resulted in reclassification regarding ICD eligibility in 10 (20 %) patients using an LVEF threshold of 35 %, and 8 (16 %) using an LVEF threshold of 30 %. Tables 1 and 2.
Table 1

LVEF Threshold 30 %

 

Echo LVEF >=30%

Echo LVEF <30%

Total

CMR LVEF >=30 %

21

1

22

CMR LVEF <30 %

7

20

27

Total

28

21

49

Kappa = 0.68

Table 2

LVEF Threshold 35 %

 

Echo LVEF >= 35 %

Echo LVEF < 35%

Total

CMR LVEF >=35%

15

3

18

CMR LVEF <35%

7

24

31

Total

22

27

49

Kappa = 0.58

 

Conclusion

In this cohort of patients being considered for ICD implantation, echocardiography systematically over-estimated LVEF. Using strict LVEF criteria, CMR changed the eligibility for ICD in a substantial proportion of patients, with, in most cases, CMR determining that the patient was ICD eligible when they were not based on echocardiography.

Authors’ Affiliations

(1)
St Michael's Hospital
(2)
Sunnybrook Health Sciences Centre
(3)
Toronto General Hospital

Copyright

© Joshi et al; licensee BioMed Central Ltd. 2011

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (<url>http://creativecommons.org/licenses/by/2.0</url>), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Advertisement