Análisis de fase para la valoración del sincronismo mecánico del ventrículo izquierdo mediante Gated-SPECT de perfusión miocárdica. Importancia de los parámetros clínicos y técnicos

Introduction:

Phase analysis (PA) of the left ventricle is a new tool in nuclear cardiology studies used to assess left ventricular mechanical timing based on different clinical applications. However, the use of this tool is relatively unknown.

Objective:

To expose the feasibility of the new PA tool in myocardial perfusion (Gated-SPECT) to assess left ventricle mechanical timing, and to verify the differences between values depending on clinical and technical conditions.

Materials and methods:

The study included consecutive patients evaluated by Gated-SPECT. The main variables were different depending on clinical and technical conditions. PA was assessed using the PHASE tool of the QPS-QGS program (Cedars-Sinai Medical Center, Los Angeles, USA). The following parameters were obtained: histogram bandwith (HB), standard deviation (SD) and entropy (E). A descriptive and analytical analysis of means and/or medians was performed using parametric or non-parametric tests. Statistical significance was p <0.05. IBM-SPSS V21® was used.

Results:

300 patients were included in this study with a mean age of 65±12.7. No differences were found in relation to the study phase (stress-rest) [HB (p=0.4), SD (p=0.6), E (p=0.8)], stress type [HB (p=0.38), SD (p=0.8), E (p=0.06), E (p=0.06)], dose used [HB (p=0.19), SD (p=0.05), E (p=0.06)], gamma camera [HB (p=0.02), SD (p=0.06), E (p=0.08)], or history of coronary heart disease [HB (p=0.44), SD (p=0.18), E (p=0.17)].

Furthermore, differences in conduction disorders were observed [HB (p=0.001), SD (p=0.02), E (p=0.001)], ejection fraction < or >35% (p=0.001), E (p=0.001)] normal or necrosis study [HB (p=0.001), SD (p=0.001), E (p=0.001)], and gender [HB (p=0.002), SD (p=0.006), E (p=0.005)].