Early effect of left coronary system revascularization on right ventricular mechanics in patients with right coronary artery chronic total occlusion

Objective No data exist on the functional relevance of collateral vessels in patients undergoing percutaneous coronary intervention (PCI). Also, the subtle effects of improved collateral flow on right ventricular (RV) function are difficult to assess. However, novel echocardiographic approaches like tissue-Doppler imaging (TDI) and two-dimensional speckle-tracking echocardiography (2DSTE) can quantify RV regional myocardial function. We hypothesized that these techniques may help delineate revascularization therapy-induced changes in regional RV contractility that escape clinical routine studies. Methods This study was a prospective registry of consecutive patients undergoing PCI for a collateral supplying artery. All included patients underwent standard echocardiography with TDI and 2DSTE to assess RV function before successful PCI and it was repeated after 24 hours and 1 month. Results There were no significant changes in either the RV systolic myocardial velocities, or the tricuspid annular plane systolic excursion values. However, RV free wall longitudinal strain/systolic strain rate values showed a significant increase 24 hours after PCI when compared to baseline (-25.9 +/- 6.8% vs. 21.5 +/- 6.6%, P < 0.001 and -2.18 +/- 0.40/s vs. -1.64 +/- 0.41/s, P < 0.001, respectively). Also, the improvement of RV function was further suggested by the tendency of RV isovolumic acceleration to be higher when compared with baseline at 1 month of follow-up (2.49 +/- 0.7 m/s(2) vs. 2.15 +/- 0.6 m/s(2), P = 0.056). Conclusion Both TDI-derived isovolumic acceleration and 2DSTE-derived strain/strain rate produced a similar picture with respect to the change in RV contractile function. However, 2DSTE indicated a much more pronounced and earlier improvement of systolic function; therefore, 2DSTE could be included in future studies that involve functional relevance of collateral vessels.