Segmental Early Relaxation Phenomenon as Determined by Tissue Doppler Imaging

Background: The early diastolic peak velocity of left ventricular (LV) wall segment has always been thought to appear in the rapid filling phase. However, we find a segmental early relaxation phenomenon (SERP), characterized by an early diastolic peak velocity lying in the isovolumic relaxation (IVR) period. The present study aimed to investigate the characteristics of SERP segments with tissue Doppler imaging (TDI) echocardiography. Methods: TDI was performed in 119 patients with known or suspected coronary heart disease (CHD) and 60 normal subjects. The segmental early diastolic velocity pattern was classified as normal pattern (NP), postsystolic shortening (PSS) and SERP. Results: Segmental early diastolic velocity pattern was significantly associated with actual coronary diameter stenosis, relative coronary stenosis, wall motion score, and segmental location in LV wall. Compared with other segments, SERP segments had a higher IVR velocity and lower early diastolic peak velocity. Conclusion: SERP most frequently occurs in the distribution of artery with the relatively mildest stenosis, and is more likely accompanied by simultaneous PSS elsewhere in LV wall, which occurs most frequently in the distribution of artery with the relatively most severe stenosis. A decreased early diastolic peak velocity of SERP segment dose not necessarily mean impaired myocardial relaxation.