Intracoronary pressures to predict myocardial viability in patients with ischemic left ventricular dysfunction

Abstract

To investigate the role of intracoronary pressure parameters in the assessment of viability in the myocardium subtending a significant coronary stenosis. In patients with ischemic left ventricular dysfunction, the presence of myocardial viability is related to the expected benefits derived from coronary revascularization.Intracoronary pressure wire-based measurements were performed in 64 coronary lesions of ≥50% stenosis severity of 59 patients with postischemic left ventricular dysfunction, segmental left ventricular wall motion abnormalities, and substantial viability in the myocardial territory subtending the investigated stenotic coronaries, defined as the percent summed rest score in the target territory (%SRS target ) ≤60% at the single-photon emission tomography. Invasive pressure-derived indexes like resting and hyperemic Pd/Pa, ΔPd/Pa, and %ΔPd/Pa (defined as the absolute difference and percent decrease between resting and hyperemic Pd/Pa respectively) were compared with %SRS target . A significant correlation was found between ΔPd/Pa (Spearman's p: −0.760, p < 0.001) and %ΔPd/Pa (p: −0.733; p < 0.001) with %SRS target. These results were confirmed after correction for potential confounders.According to %SRS target median value, myocardial areas with high and low viability were compared: ΔPd/Pa and %ΔPd/Pa were significantly higher in areas with high viability (p < 0.001 for both). According to receiver operating characteristic curves, we identified two cut-offs (ΔPd/Pa > 0.11 and %ΔPd/Pa > 15%) able to predict >80% viability with good sensitivity and specificity. Our study suggests that, in patients with postischemic left ventricular dysfunction and significant coronary stenosis, intracoronary pressures indexes like ΔPd/Pa and %ΔPd/Pa are able to predict the magnitude of downstream myocardial viability.

Clinical impact of multimodality assessment of myocardial viability

“…This leads to a reduction in the trans-stenotic gradient and, consequently, a higher FFR value. 17,18 Furthermore, the FFR value has been identified as the most significant predictor of left ventricular functional recovery, along with myocardial viability assessment, following dobutamine stress. Coronary flow reserve (CFR) represents a valuable tool for the assessment of microvascular dysfunction in patients presenting with both ischemia with non-obstructive coronary arteries (INOCA) and myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA).…”

“…The proportion of viable tissue to be perfused in the territory supplied by the stenotic coronary vessel decreases subsequently due to reduced oxygen consumption, microcirculatory occlusion, and resistance vessels dysfunction in the infarcted area. This leads to a reduction in the trans‐stenotic gradient and, consequently, a higher FFR value 17,18 . Furthermore, the FFR value has been identified as the most significant predictor of left ventricular functional recovery, along with myocardial viability assessment, following dobutamine stress.…”