Septal flash as a predictor of cardiac resynchronization therapy
response: A systematic review and meta-analysis
Abstract
Background: Cardiac resynchronization therapy (CRT) in heart failure
patients has been shown to improve patient outcomes in some but not all
patients. A few studies have identified that septal flash on imaging is
associated with response to CRT but there has yet to be systematic
review to evaluate consistency of the finding across the literature.
Methods: A search of MEDLINE and EMBASE was conducted to identify
studies which evaluate septal flash and its association with CRT
response. Studies that met the inclusion criteria were statistically
pooled with random-effects meta-analysis and heterogeneity was assessed
using the I2 statistic. Results: A total of nine
studies were included with 2,307 participants (mean age 76 years, 67%
male). Septal flash on imaging before CRT implantation was seen in 53%
of patients and the proportion of CRT responders from the included
studies varied from 52% to 77%. In patients who were CRT responders,
septal flash was seen in 40% of patients compared to 10% in those
deemed to be CRT non-responders. Meta-analysis of the eight studies
suggests that the presence of septal flash at pre-implant was associated
with an increased likelihood of CRT response (RR 2.55 95%CI 2.04-3.19,
p<0.001, I2=51%). Septal flash was also reported to be
associated with left ventricular reverse remodelling but the association
with survival and symptomatic improvement was less clear. Conclusions:
Septal flash is a well-defined and distinctive contraction pattern which
is consistently associated with CRT response and should be evaluated
when assessing for appropriateness of CRT device.