Impact of viability and scar tissue on response to cardiac resynchronization therapy in ischaemic heart failure patients

Abstract

The extent of scar tissue and viable myocardium were directly related to the response to CRT. Furthermore, scar tissue in the LV pacing lead region may prohibit response to CRT. Evaluation for viability and scar tissue may be considered in the selection process for CRT.

Repeatability and reproducibility of phase analysis of gated single-photon emission computed tomography myocardial perfusion imaging used to quantify cardiac dyssynchrony

“…The presence, location, and severity of myocardial scar have been shown to impact patient response to CRT in a retrospective study using cardiac magnetic resonance imaging [41]. Recently, the extent of myocardial variability as assessed by F-FDG SPECT has also been shown to predict response to CRT [42]. Finally, the addition of dyssynchrony evaluation in patients having gated SPECT perfusion studies performed for other indications would be very cost effective and could potentially obviate the need for additional diagnostic testing.…”

Regional myocardial contractile reserve assessed by strain echocardiography and the response to cardiac resynchronization therapy

“…Myocardial segments with tracer uptake of more than 75% were labeled as viable, segments with 50-75% of maximal tracer activity were considered to contain scar of small extent (non-transmural) and segments with less than 50% tracer uptake were considered to contain excessive scar (transmural infarction). Patients with transmural scar (n = 15, 29% of patients) did not show clinical improvement, reverse remodeling of LV or increase in LV function after 6 months follow-up [12].…”

Myocardial Viability Assessment is Still Alive and an Important Element in Predicting Prognosis and Providing Optimal Management for Ischemic Heart Failure

“…Another predictor of responders to CRT is extent of scar tissue and viable myocardium. [49,53,54,55] Summed rest score (SRS) is quantified as an index of scar extent on myocardial perfusion SPECT. SRS ≥ 27 predicts lack of response to CRT (Figure 8) [48].…”