Maffessanti Francesco, Wanten Joris, Potse Mark, Regoli Francois, Caputo Maria Luce, Conte Giulio, Sürder Daniel, Illner Annekatrin, Krause Rolf, Moccetti Tiziano, Auricchio Angelo, Prinzen Frits W
Center for Computational Medicine in Cardiology, USI, Lugano, Switzerland.
Maastricht University, Maastricht, The Netherlands.
Int J Cardiol. 2017 Aug 15;241:270-276. doi: 10.1016/j.ijcard.2017.02.056. Epub 2017 Feb 22.
Both duration and morphology of the T-wave are regarded important parameters describing repolarization of the ventricles. Conventionally, T-wave concordance is explained by an inverse relation between the time of depolarization (TD) and repolarization (TR). Little is known about T-wave morphology and TD-TR relations in patients with heart failure.
Electro-anatomic maps were obtained in the left (LV) and right ventricle (RV) and in the coronary sinus (CS) in patients with heart failure with narrow (nQRS, n=8) and wide QRS complex with (LBBB, n=15) and without left bundle branch block (non-LBBB, n=7). TD and TR were determined from the thus acquired electrograms.
In nQRS and non-LBBB patients, TD-TR relations had a slope between 0 and +1, indicating that repolarization followed the sequence of depolarization. In LBBB patients, repolarization occurred significantly earlier in the RV than in the LV, fitting with the idea that the discordant T-waves in LBBB are secondary to the abnormal depolarization sequence. However, the slopes of the TD-TR relations in the LV and CS were not significantly different from zero, indicating no major spatial gradient in LV repolarization, despite a considerable gradient in depolarization. Remarkable was also the large (~100ms) transseptal gradient in repolarization. Values of the slopes of the TD-TR relation overlapped between the three patient groups, despite a difference in T-wave morphology between LBBB (all discordant) and nQRS patients (all flat/biphasic).
Discordant T-waves in LBBB patients are explained by interventricular dispersion in repolarization. T-wave morphology is determined by more factors than the TD-TR relation alone.
T波的持续时间和形态均被视为描述心室复极化的重要参数。传统上，T波一致性是通过去极化时间（TD）和复极化时间（TR）之间的反比关系来解释的。关于心力衰竭患者的T波形态以及TD-TR关系，人们所知甚少。
在患有窄QRS波（nQRS，n = 8）、宽QRS波伴左束支传导阻滞（LBBB，n = 15）和不伴左束支传导阻滞（非LBBB，n = 7）的心力衰竭患者中，获取左心室（LV）、右心室（RV）和冠状窦（CS）的电解剖图。通过由此获得的心电图确定TD和TR。
在nQRS和非LBBB患者中，TD-TR关系的斜率在0到+1之间，表明复极化遵循去极化顺序。在LBBB患者中，RV的复极化明显早于LV，这与LBBB中不一致的T波继发于异常去极化顺序的观点相符。然而，LV和CS中TD-TR关系的斜率与零无显著差异，这表明尽管去极化存在相当大的梯度，但LV复极化没有主要的空间梯度。复极化中显著的（约100ms）跨间隔梯度也很明显。尽管LBBB（所有不一致）和nQRS患者（所有平坦/双相）的T波形态不同，但TD-TR关系斜率的值在三组患者之间重叠。
LBBB患者中不一致的T波是由复极化的心室间离散所解释的。T波形态由比单独的TD-TR关系更多的因素决定。
