Left ventricular volumes on positron emission tomography: validation against cardiovascular magnetic resonance

Cardiovascular magnetic resonance (CMR) is the gold standard for determination of left ventricular volumes (LVV), including end diastolic volume (LVEDV) and end systolic volume (LVESV). With incorporation of ECG gating, the quantitative analysis of ventricular function can be achieved in Positron Emission Tomography (PET) studies. However, the accuracy of LVV quantification using PET has not been shown in previous studies.

We aimed to assess the inter-study variability of LVEDV and LVESV between CMR and PET.

Consecutive patients who underwent both PET and CMR within 1 year were identified from prospective institutional registries. LVV on PET was compared against CMR as a reference standard using several statistical measures of agreement.

The study population consisted of 233 patients (mean age 60.8±13.6 years, 64.8% male). The median (IQR) duration between CMR and PET was 41 (11–96) days. The median (IQR) LVEDV values were 144 (107–196) on PET and 178 (138–236) on CMR (mean difference 36.09±2.36, p<0.001). As shown in Figure 1, there was a good correlation (Spearman rho=0.88, p<0.001; Intraclass Correlation Coefficient 0.88, 95% CI 0.84–0.90, P<0.001) with moderate limits of agreement (95% limits of agreement −108.17–35.99). A total of 0% and 3.9% of the cohort had LVEDV >150 ml/m² by CMR and PET respectively. Overall results were similar with LVESV values and similar in subgroup analysis of patients with a low EF (<40%), a coronary artery disease scar, LV hypertrophy and of patients with defibrillators.

Our analysis has shown a good correlation of LVV between PET and CMR, indicating PET derived LVV can accurately be used in the diagnosis and management of patients.

Type of funding sources: None.