P1471Multimodality imaging of left ventricular function and volumes in patients with acute and chronic myocardial injury - Novel insights

Abstract Introduction The three main techniques to evaluate myocardial function and volumes: two-dimensional echocardiography (TTE), gated single photon emission computed tomography (SPECT) and cardiac magnetic resonance imaging (cMRI), have important differences in accessibility and practicality. Purpose We aimed to evaluate: TTE, SPECT and cMRI in the measurement of left ventricular ejection fraction (LVEF), left ventricular end-diastolic (LVEDV) and left ventricular end-systolic volumes (LVESV) in patients with acute and chronic myocardial ischemic injury. Methods Consecutive patients with first large acute myocardial infarction (AMI) [LVEF ≤45% and/or cMRI infarct size ≥10% of left ventricle, 2–5 days after pPCI, n=10] and patients with chronic ischemic heart failure (CIHF) [LVEF ≤45% by SPECT, NYHA class II or III, n=10] were enrolled. Multimodality imaging using the study techniques was performed within 36 hours. Results LVEF measured with TTE, SPECT and cMRI did not differ between both groups (AMI: 41±2.5%, 37.9±2.7%, 41±2.7%; p=0.07, CHF: 29.6±3.2%, 29.7±3.0%, 32.9±4.9%; p=0.42). LVEDV and LVESV evaluated by SPECT were +33.6%, +38.2% higher in the AMI group and +40.7%, 40.4% higher in the CIHF group compared with TTE (p<0.001). When measured with cMRI they were +52.1%, +50.5%, +31.5%, +25.5% higher (AMI, CIHF group, respectively), compared with TTE (p<0.001). There was a strong positive correlation between LVEF derived from TTE and SPECT (r=0.81, AMI; r=0.92, CIHF), TTE and cMRI (r=0.89, AMI; r=0.75, CIHF), SPECT and cMRI (r=0.88, AMI; r=0.76, CIHF; all p<0.01). As well as for LVEDV (r=0.79, 0.88; 0.90, 0.85; 0.76, 0.87; all p<0.05) and LVESV measurements (r=0.90, 0.91; 0.94, 0.89; 0.85, 0.85, all p<0.05). Figure 1 Conclusions There is a strong correlations between TTE, SPECT, and cMRI in the assessment of left ventricular function in patients with AMI or CIHF. However, TTE appears to significantly underestimate left ventricular volumes in relation to SPECT and cMRI.