Number 08-01 Measuring Dyssynchrony in Pulmonary Hypertension
Case from: Dirk Lossnitzer, Nael F. Osman, Henning Steen, Franz J. Meyer, Evangelos Giannitsis Depts of Cardiology/Respiratory Medicine, University Hospital, Heidelberg, Germany and Dept of Radiology, Johns Hopkins University, Baltimore, Maryland, USA Clinical history: A stable, idiopathic pulmonary artery hypertensive (IPAH) 38 year old female (PAP 110 mmHg, WHO functional class III) underwent CMR.
Cine CMR: Typical IPAH findings: the RV was dilated, hypertrophic with severely decreased systolic function. The LV was normal but compressed with the interventricular septum showing paradoxal endsystolic movement towards the LV cavity.
Additional techniques: SENC Images. For evaluation of interventricular dyssynchrony, strain-encoded (SENC) imaging was performed. SENC images (temporal resolution 25ms, diastole and systole) showed preserved strain in the free RV wall whereas a delay in peak circumferential strain of about 75-100 ms was detectable compared to LV.
The colored movie shows the circumferential shortening as red coloring of the myocardium. The graphs of the bottom show the circumferential strain (Ecc) in the free RV wall (red curves), septum (green curves) and LV lateral wall (blue curves), where the negative values indicate expected shortening in the circumferential direction.
Perspective: Using SENC, preserved RV free wall strain was demonstrated despite apparent RV systolic failure. Furthermore, relevant RV delay which was not obvious by visual appraisal could be uncovered by SENC. Therefore SENC may provide valuable additional information on RV dysfunction in IPAH.
Reference: Pan L et al. Real-time Imaging of Regional Myocardial Function Using Fast-SENC. MRM 1006;55:386-395