Author + information
- Christoph Langer,
- Mark Luedde,
- Philipp Schaefer,
- Mirko Hohnhorst,
- Matthias Lutz,
- Matthias Eden,
- Christine Gierloff,
- Christian Prinz,
- Lothar Faber and
- Norbert Frey
Patients (pts) with hypertrophic cardiomyopathy (HCM) may present with a variety of symptoms, including sudden cardiac death. Sudden cardiac death due to ventricular fibrillation correlates with the extent of intramural fibrosis (IF). IF can be detected using cardiac magnetic resonance (CMR) by showing “late enhancement” (LE) in such areas. However, there are a number of CMR contraindications supporting the need for alternative imaging modalities. Cardiac CT was shown to demonstrate subendocardial LE following myocardial infarction. We now investigated Cardiac CT in HCM patients with IF.
In an ongoing prospective study approved by the local ethics committee and the German Federal Office for Radiation Protection we recruit consecutive pts with echocardiographically suspected HCM (septum >15mm). For assessment of ventricular configuration, volumetry and IF all patients undergo cardiac CT followed by CMR for validation. Cardiac CT scans (64-slices; tube voltage 80 kV) are run 7 minutes after dye injection. Analysis of IF is based on multi-planar reconstructions (detection, intensity, volumetry) and the established 17-segment polar map (distribution). Planimetry is performed by both a skilled cardiologist and radiologist.
27 pts were recruited (men n=16, women n=11; 65.0 ± 14.3 years of age; echo: septum 18.4 ± 2.2 mm, E/A 0.87 ± 0.29). Cardiac CT detected IF in 51.7 % (15/29 pts) whereas CMR demonstrated IF in 69.0 % (20/29 pts). IF distribution was congruent: segment 2 in 5 pts, segment 3 in 2 pts, segment 4 in 2 pts, segment 5 in 3 pts, segment 6 in 1 pts, segment 8 in 2 pts, segment 9 in 1 pts, and segment 10 in 1 pts. Of note, in CMR artefacts were visible in 34.5 % (10/29 pts). In Cardiac CT, LE representing IF and non-enhanced myocardium revealed an average HU value of 130.79 ± 20.68 vs. 95.65 ± 15.26 (p 0.000024); IF volume was 4.9 ± 3.85 mm3. The intra-/interobserver variability was r=0.88 (p=0.37) and r=0.88 (p=0.41), respectively. The effective dose using our protocol was for men 3.43 ± 0.57 mSv and for women 4.98 ± 1.06 mSv.
Cardiac CT can reliably detect, localize and quantify IF in HCM patients.
Poster Sessions, Expo North
Saturday, March 09, 2013, 3:45 p.m.-4:30 p.m.
Session Title: Imaging: CT/Multimodality IV
Abstract Category: 20. Imaging: CT/Multimodality
Presentation Number: 1182-349
- 2013 American College of Cardiology Foundation