Background: Cardiac magnetic resonance imaging (CMRI) is an important tool to assess cardiac function. However, one of the limitations of CMRI is the need for frequent breath-holding (BH) steps. This may be inconvenient to some patients and limit the use of this modality in patients unable to cooperate because of cognitive reasons or physically incapable of performing the required BH steps. The purpose of this study is to overcome the intrinsic timing and computation limitations of dual-navigator cine imaging and demonstrate the feasibility of free-breathing (FB) cine cardiac left ventricular function with a single-respiratory-navigator gating at 3 T.
Results: Eight participants underwent cine CMRI with both the conventional 2-dimensional cine BH and FB navigator-gated techniques. Scan parameters were identical, except in the FB technique, in which a respiratory navigator and only 2 signal averages were used. Images were scored for quality. Left ventricular end-systolic volume and end-diastolic volume were calculated. The differences in the end-systolic volume and end-diastolic volume assessed by the BH and FB were not statistically significant with P = 0.9 and 0.2, respectively. There was a good agreement between LV volumes with the limits of agreement (±2 SD = ±22.36 mL). Image quality score was not significantly different (P = 0.76).
Conclusions: Free-breathing cine imaging utilizing a single-respiratory-navigator gating technique is comparable to conventional BH technique in both qualitative and quantitative imaging measures. Therefore, the FB cine technique can be used as an alternative for children and patients who are unable to hold their breath.
From the *Integrative Cardiovascular Imaging Section, The National Institute of Diabetes and Digestive and Kidney Diseases, and †Radiology and Imaging Sciences Department, National Institutes of Health, Bethesda, MD.
Received for publication December 22, 2010; accepted March 17, 2011.
Reprints: Ahmed M. Gharib, MD, Clinical Research Center, National Institutes of Health, Bldg 10, Rm 3-5340, 10 Center Dr, Bethesda, MD 20892 (e-mail: email@example.com).
K.A.-E. and C.C.O. contributed equally to this work.
This research year was made possible through the Clinical Research Training Program, a public-private partnership supported jointly by the National Institutes of Health and Pfizer Inc (via a grant to the Foundation for the National Institutes of Health from Pfizer Inc).