We used 2-dimensional speckle tracking echocardiography for determining circumferential strain (x-axis) and radial displacement (y-axis) in patients with constrictive pericarditis (CP), patients with restrictive cardiomyopathy (RCM), and control subjects (CON). Each plotted value represents peak end-systolic circumferential strain and radial displacement values averaged from apex, mid, and basal segments for 3 consecutive heartbeats. On combining the data from the 3 groups, peak radial displacement showed good correlation with peak circumferential shortening strains.

Peak end-systolic circumferential strain (x-axis) was averaged from basal, mid, and apical short-axis views for 3 consecutive heartbeats. Rotations in either the basal or apical short-axis planes were expressed as average angular displacements of 6 myocardial segments along the central axis. Net left ventricular (LV) twist (y-axis) was calculated as the net difference between LV peak rotation angles obtained from the basal and apical short-axis planes and averaged over 3 consecutive heartbeats. On combining the data from the 3 groups (CP, RCM, and CON), a good correlation was seen between peak circumferential shortening strains and peak net ventricular twist. Abbreviations as in Figure 1.

Distribution of peak early diastolic longitudinal velocity (A), longitudinal displacement of the LV base (B), peak early diastolic apical untwisting velocity (C), and net ventricular twist (D) has been shown for patients with CP and RCM. In comparison with RCM, patients with CP had significantly higher longitudinal early diastolic velocity (E_m) and markedly attenuated untwisting velocity (E_r). Both velocities, when considered in isolation, however, show substantial overlap (E_m: 21 of 45 [47%]; longitudinal displacement: 36 of 45 [80%]; E_r: 23 of 45 [51%]; LV torsion: 24 of 45 [53%]). Abbreviations as in Figures 1 and 2.

Receiver-operating characteristic curves of E_m, E_r, and net LV twist (T) have been plotted for differentiating CP from RCM. Optimal cut-off value for E_m was 5 cm/s (92% sensitivity and 90% specificity); E_r was –50°/s (57% sensitivity and 95% specificity); and net LV twist was 10° (83% sensitivity and 84% specificity). The area under the receiver-operating characteristic curve was significantly higher for early diastolic longitudinal velocities as compared with early diastolic untwisting velocities (p = 0.01). Abbreviations as in Figures 1 to 3.

Color M-mode display of apical untwisting velocity (rotational rate of the LV apex [RotR]) obtained from speckle tracking of the LV apex in short-axis view shows markedly attenuated early diastolic rate of untwisting in CP (A, arrows), whereas longitudinal early diastolic velocities (VL) from the LV base in apical 4-chamber view (B, arrows) are normal. In contrast, patients with RCM show a normal early diastolic rate of untwisting (C, arrows) and reduced longitudinal early diastolic velocities from the LV base (D, arrows). Abbreviations as in Figures 1 and 2.

Early diastolic velocity >–5 cm/s and/or early diastolic apical untwisting velocity –50°/s separated the patients with CP and RCM with overlapping values seen in only 1 patient with CP. This finding provides a rationale for combining longitudinal early diastolic velocities with rotational untwisting velocities for differentiating the 2 disparate patterns of diastolic restoration mechanics seen in CP and RCM. Abbreviations as in Figure 1.