Optimized assessment for establishing myocardial viability prior to revascularization of a chronic total coronary occlusion using cardiac magnetic resonance imaging

Introduction

Predictive value of delayed enhancement CMR is moderate especially in segments with an intermediate transmural extent of infarction (TEI).

Purpose

We sought to improve the predictive value of cardiac magnetic resonance imaging (CMR) using combined viability assessment in patients before percutaneous coronary intervention (PCI) of a chronic total coronary occlusion (CTO).

Methods

We studied patients with a successful (43/71) and without a successful (29/71) PCI of a CTO. Segmental wall thickening (SWT) was quantified before and after PCI. Before PCI, using CMR, 5 viability indexes were evaluated: TEI, contractile reserve during dobutamine, end diastolic wall thickness (EDWT), unenhanced rim thickness and SWT of the unenhanced rim (SWTur). We determined predictive value for improvement in SWT>10% after PCI for each viability index and for combined viability assessment.

Results

Mean SWT improved significantly in patients with successful PCI (16 ± 19% to 39 ± 35 %; p < 0.0001), mean SWT did not improve in patients without successful PCI (19 ± 21% to 21 ± 25%; p = 0.54). Predictive value for each viability index is presented in Table 1. Combined viability assessment using contractile reserve during dobutamine, SWTur and TEI, improved the predictive value with a sensitivity of 92%(95% CI 82–97) and specificity of 83%(95% CI 70–91).

Table 1 Diagnostic performance of each viability index for the prediction of improvement in SWT.

Conclusion

Combined viability assessment was superior to viability assessment using a single parameter. This may be useful for the selection of patients for PCI of a CTO.