30 patients (22 males) were referred for:  heart valve disease (n=9), ischemic cardiopathy (n=8), myocarditis (n=5), left ventricular hypertrophy (n=5) and infiltrative cardiomyopathy (n=3). Mean age was 48.0 ± 21.0 years-old. All patients could fully complete CS_rt and CS_rg breath-holdings.

Mean scan time was 485.4 ± 83.3 s (95 % CI: 454.3 to 516.5) using SSFP_ref. Regarding CS accelerated sequences, mean scan time was 23.9 ± 5.2 s (95 % CI: 21.9 to 25.8) with CS_rt and 58.3 ± 15.1 s (95 % CI: 53.7 to 64.2) with CS_rg (p < 0.0001).

Compared to SSFP_ref, the mean acceleration factor reached by CS_rg was 8.4 (95 % CI: 7.5 to 9.3). A mean number of 15.0 ± 1.2 slices (95 % CI: 14.6 to 15.4) was acquired with each technique. 

The CS_rg prototype demonstrated a significantly better edge sharpness than CS_rt (CS_rg = 0.083 ± 0.013 pixel^-1 [95 % CI: 0.078 to 0.087] versus CS_rt = 0.070 ± 0.011 pixel^-1 [95% CI: 0.066 to 0.074]; p = 0.0004) (Fig. 4).

Moreover, no significant difference was demonstrated between CS_rg and SSFP_ref (CS_rg = 0.083 ± 0.013 pixel^-1 [95 % CI: 0.078 to 0.087] versus SSFP_ref = 0.075 ± 0.016 pixel^-1 [95% CI: 0.069 to 0.081]; p = 0.0516) (Fig. 5).

Good agreement were yielded by Bland-Altman and linear regression analyses for both LV (R² > 0.92) and RV (R² > 0.89). No significant difference was demonstrated regarding LVM or LV and RV volumes (EDV, ESV, SV) and EF (p > 0.05) (Table 1).

Intra-rater agreement was excellent, demonstrating intraclass correlation coefficient (ICC) greater than 0.99 for both ventricles. So were inter-rater agreement for LV (ICC ≥ 0.97) and RV (ICC ≥ 0.96).