RESUMO
To explore left ventricular filling patterns in patients with a history of previous myocardial infarction (MI) using time-volume curves obtained from conventional cine-cardiac magnetic resonance (CMR) examinations. Consecutive patients with a history of previous MI who were referred for CMR evaluation constituted the study population, and a consecutive cohort of sex and age-matched patients with a normal CMR constituted the control group. The following CMR diastolic parameters were evaluated: peak filling rate (PFR), time to PFR (tPFR), normalised PFR adjusted for diastolic volume at PFR (nPFR), and percent RR interval between end systole and PFR. Fifty patients were included, 25 with a history of previous MI and 25 control. The mean age was 59.6 ± 13.9 years and 27 (54%) were male. Within the control group, age was significantly related to PFR (r = -0.53, p = 0.007), whereas among patients with previous MI age was not related to PFR (r = -0.16, p = 0.44). PFR (252.4 ± 96.7 ml/s vs. 316.0 ± 126.4 ml/s, p = 0.05) and nPFR (1.6 ± 1.2 vs. 3.3 ± 1.5, p < 0.001) were significantly lower in patients with previous MI, whereas no significant differences were detected regarding tPFR (143.0 ± 67.5 ms vs. 176.2 ± 83.9 ms, p = 0.13) and % RR to PFR (18.1 ± 9.7% vs. 20.6 ± 12.2%, p = 0.44). MI size was related to LV ejection fraction (r = -0.76, p < 0.001), PFR (r = -0.40, p = 0.004), nPFR (r = -0.52, p < 0.001) and left atrium area (r = 0.40, p = 0.004). Patients at the lowest PFR quartile (<200 ml/s) showed a larger MI size (Q1 26.5 ± 25.5%, Q2 15.5 ± 20.9%, Q3 6.3 ± 12.4%, Q4 8.8 ± 14.1%, p = 0.04). At multivariate analysis, MI size was the only independent predictor of the lowest PFR (p = 0.017). Infarct size has an impact on LV filling profiles, as assessed by conventional cine CMR without additional specific pulse sequences.
