Patients who do not fulfill criteria for hypertrophic cardiomyopathy but have unexplained giant T-wave inversion: a cardiovascular magnetic resonance mid-term follow-up study

Fig. 1. The flow chart depicts patient enrollment secondary to inclusion and exclusion criteria. Patients’ selection process and exclusion criteria. HCM hypertrophic cardiomyopathy, CMR cardiovascular magnetic resonance

Fig. 2. Representative cases of patients with unexplained giant T-wave inversions on electrocardiogram (ECG). Patient 1 (a–d) a 59-year-old male and is a typical case from Group 1. a and b show the two chamber and 4 chamber end-diastolic balanced steady state free precession (bSSFP) cine images respectively at baseline. c and d were the corresponding 2 and 4 chamber end-diastolic bSSFP cine images at follow-up 48 months later when this patient fulfilled criteria for apical HCM. Patient 2 (e–h) is a 57 years-old male and represents a typical case from Group 2. e and f show the 2 chamber and 4 chamber end-diastolic bSSFP cine phases respectively at baseline. f and g show the 2 and 4 chamber cine views, respectively, 32 months later. The wall thickness of apex has become became (average 35% increased) when compared to baseline, however the absolute value does not meet the diagnostic criteria for apical HCM

Fig. 3. The head-to-head comparison of the changes of all 16-segmental thicknesses of the left ventricle (LV) in patients who did not meet HCM criteria (wall thickness ≥ 15 mm without family history or ≥ 13 with a family history of HCM) at baseline or at follow-up between group 1 (a) and group 2 (b). at follow-up, the thickness of all LV segments significantly increased. The thickness of apical portion (segment 13–16) increased the most. Seg segment

Fig. 4. Comparison of LV wall thickness for all 16 segments in patients who had apical wall thickness < 15 mm without a family history or < 13 with a family history of HCM) at baseline (a) and at follow-up (b) for both groups. There were no significant differences both in basal (seg 1–6) and middle (seg 7–12) at either baseline and follow-up. However, there were significant differences in apical segments (seg 13–16) both at baseline and follow-up. FH family history, Seg segment

Fig. 5. Receiver operating curves (ROC) showed that the predictive performance of single (a) and joint (b) CMR parameters for apical HCM. Mean apical thickness (+ ApA) is the best predictor for apical HCM, which had an AUC of 0.898, a sensitivity of 93.8%, and a specificity of 85.5% (p < 0.001). Max maximum, LV left ventricular, LVEF left ventricular ejection fraction

Fig. 6. Relationship between the time intervals of CMR examinations and the maximum absolute increase in LV wall thickness in all patients (a), Group 1 (b) and Group 2 (c). The relationship between time intervals of CMR examinations and maximum percentage of increased segmental thickness at the apex (segmental 13–16) is shown in all patients (d), Group 1 (e) and Group 2 (f). CI indicates confidence interval

Fig. 7. Bland Altman analysis of the apical angle (ApA), wall thickness (WT) of segment 2, and wall thickness for segment 13 for intra- and inter-observer variability in this cohort. Variability of intra-observer (a) and inter-observer (b) for ApA, intra-observer (c) and inter-observer (d) for segment 2 wall thickness, and intra-observer (e) and inter-observer (f) for segment 13 are shown. The middle-dashed line indicates the mean difference and gray area between dash lines indicates the standard deviation