利用磁共振成像确定左心室长轴方向：正常及患病受试者在呼吸和心动周期中的变化

Determination of left ventricular long-axis orientation using MRI: changes during the respiratory and cardiac cycles in normal and diseased subjects.

作者信息

Foster John E, Engblom Henrik, Martin Thomas N, Wagner Galen S, Steedman Tracey, Ferrua Stefania, Elliott Alex T, Dargie Henry J, Groenning Bjoern A

机构信息

Glasgow Cardiac Magnetic Resonance Unit, Glasgow, Lanarkshire, UK.

出版信息

Clin Physiol Funct Imaging. 2005 Sep;25(5):286-92. doi: 10.1111/j.1475-097X.2005.00624.x.

DOI:10.1111/j.1475-097X.2005.00624.x

PMID:16117732

Abstract

BACKGROUND

It has previously been shown that magnetic resonance imaging (MRI) can be used to accurately determine left ventricular (LV) long-axis orientation in healthy individuals. However, the inter- and intra-observer variability in patients with acute coronary syndrome (ACS) and chronic heart failure (CHF) has not been explored. Furthermore, the changes in LV long-axis orientation because of respiration and during the cardiac cycle remain to be determined.

METHODS

LV long-axis orientation was determined by MRI in the frontal and transverse planes in 44 subjects with no cardiac disease, 20 ACS patients and 13 CHF patients. Changes in LV long-axis orientation because of respiration were assessed in a subset of 25 subjects. Changes during the cardiac cycle were assessed in six subjects from each subject group. Reproducibility was assessed by a re-examination of 17 subjects after 28 days.

RESULTS

The inter- and intra-observer variability for LV long-axis orientation was low for all subject groups. The difference between the baseline and the 28 days examinations was -1.4+/-5.9 degrees and -0.8+/-4.4 degrees in the frontal and transverse planes, respectively. No significant change in LV long-axis orientation was found between end-expiration and end-inspiration (frontal plane, P=0.63 and transverse plane, P=0.42; n=25). No significant difference in change of the LV long-axis orientation during the cardiac cycle was found between the subject groups (frontal plane, chi-square 1.8, P=0.40 and transverse plane, chi-square 5.7, P=0.06).

CONCLUSIONS

There is a low inter-and intra-observer variability and a high reproducibility for determining LV long-axis orientation in patients with no cardiac disease as well as in patients with ACS or CHF. There is no significant change in LV long-axis orientation due to respiration, and only small changes during the cardiac cycle in these groups.

摘要

背景

此前已有研究表明，磁共振成像（MRI）可用于准确测定健康个体的左心室（LV）长轴方向。然而，急性冠状动脉综合征（ACS）和慢性心力衰竭（CHF）患者中观察者间及观察者内的变异性尚未得到探究。此外，左心室长轴方向因呼吸和心动周期而发生的变化仍有待确定。

方法

通过MRI在额面和横断面上测定44名无心脏病受试者、20名ACS患者和13名CHF患者的左心室长轴方向。在25名受试者的子集中评估因呼吸导致的左心室长轴方向变化。在每个受试者组的6名受试者中评估心动周期中的变化。通过对17名受试者在28天后进行重新检查来评估可重复性。

结果

所有受试者组中，左心室长轴方向的观察者间及观察者内变异性均较低。额面和横断面上，基线检查与28天检查之间的差异分别为-1.4±5.9度和-0.8±4.4度。呼气末和吸气末之间未发现左心室长轴方向有显著变化（额面，P = 0.63；横断面，P = 0.42；n = 25）。各受试者组之间在心动周期中左心室长轴方向变化方面未发现显著差异（额面，卡方值1.8，P = 0.40；横断面，卡方值5.7，P = 0.06）。