Análisis de fase en estudios Gated-SPECT como predictor de mortalidad en pacientes con enfermedad coronaria y función ventricular izquierda deprimida

Abstract

BackgroundCoronary disease is one of the main causes of morbidity and mortality in western countries. In the advanced stages of the disease the myocardial remodelling processes can lead to progressive heart failure and left ventricular impairment. The phase analysis of Gated-SPECT studies of myocardial perfusion show parameters that have been characterised as valid marker of ventricular asynchrony. ObjectiveTo evaluate the phase analysis parameters in Gated SPECT as independent predictors of mortality in patients with advanced coronary disease and left ventricular failure. Materials and methodA retrospective historic cohort study was conducted on 185 consecutive patients (140 males; mean age = 67.6±12.7 years) on whom, between January 2009 and March 2011, an isotope myocardial perfusion study was carried out with pharmacologic stimulation and with a positive result for ischaemia / necrosis, and with a LVEF ≤ 55%. A mean follow-up of 32.4 ±10.5 months was also performed, recording the appearance of major cardiac events (non-fatal acute myocardial infarctions, hospital admission, delayed coronary revascularisation, and total mortality. ResultsMajor events were recorded in 51 patients during follow-up. There were also 28 deaths, of which 82.1% showed abnormal values of the phase parameters: media=141.1°±17.6°; standard deviation=15.8°±10.1°; bandwidth=59.1°±36°, and LVEF = 42.4%±10.8%. The Cox analysis showed the bandwidth as an independent predictor of death, significantly reducing the survival and increasing the risk of death (hazard ratio=2.68; P<.05). ConclusionsThe bandwidth in the phase analysis behaves as an independent predictive factor in patients with known myocardial disease and an impaired LVEF.