The effect of percutaneous coronary intervention of chronically totally occluded coronary arteries on left ventricular global and regional systolic function.

BACKGROUND: Percutaneous coronary intervention (PCI) is frequently attempted to open chronic total occlusions (CTOs) and restore epicardial coronary flow. Data suggest adverse outcomes in the case of PCI failure. We hypothesized that failure to open a CTO might adversely affect regional cardiac function and promote deleterious cardiac remodelling, and success would improve global and regional cardiac function assessed using cardiac magnetic resonance and velocity vector imaging.

METHODS: Thirty patients referred for PCI to a CTO underwent cardiac magnetic resonance examination before and after the procedure. Left ventricular function and transmural extent of infarction was assessed in these patients. Regional cardiac function using Velocity Vector Imaging version 3.0.0 (Siemens) was assessed in 20 patients.

RESULTS: Successful CTO opening (thrombolysis in myocardial infarction 3 flow) occurred in 63% of patients. Left ventricular ejection fraction significantly increased after successful PCI (50 ± 13% to 54 ± 11%; P < 0.01). Global longitudinal strain (GLS) fell significantly in the failed group (Δ = -25 ± 17%; P = 0.02) in contrast with successful PCI in which GLS did not change (Δ 20 ± 32%; P = 0.17). GLS rate followed a pattern similar to GLS (failed, Δ -30 ± 17%; P < 0.01 vs success Δ 25 ± 48%; P = 0.34). In contrast, radial and circumferential strain/strain rate were not different between groups after success/failed PCI.

CONCLUSIONS: Regional cardiac function assessment using velocity vector imaging showed a significant decline in GLS and GLS rate in patients in whom PCI failed to open a CTO, with no change in global measures of cardiac function.