Left ventricular untwist in patients with diastolic dysfunction: speckle tracking imaging study

Background There is no single noninvasive index that can directly assess diastolic function. Untwist contributes to diastolic suction and early filling. Speckle tracking imaging (STI) can be used to study the relation between diastolic indices and untwist in patients with diastolic dysfunction.Patients and methods A total of 75 patients with diastolic dysfunction and 25 normal volunteers were selected for this study. According to mitral flow pattern, the patients were classified into group I (abnormal relaxation), group II (pseudonormalized), and group III (stiffness pattern). Using STI, the basal and apical short-axis views were imaged. Stored data were processed to get apical and basal rotation, systolic twist, peak systolic twist ratio, diastolic untwist ratio, and time to peak twist and untwist ratio.Results Peak untwisting ratio was significantly higher in Group I Patients that decreased to be normalized and even decreased with progression of diastolic dysfunction from Group II to Group III. There was a highly significant positive and negative correlation with end-diastolic volume and end-systolic volume, respectively. Time to peak untwist ratio nonsignificantly increased from group I to III, with nonsignificant correlation between untwist ratio and peak E, A, and E/A ratio.Conclusion Patients with relaxation abnormality have a higher untwist ratio, which decreases gradually with progression from relaxation to stiffness pattern. It may appear as a compensatory mechanism to ensure early filling with relaxation abnormality.