Left Ventricular Filling Pressure as a Useful Marker of Myocardial Injury Following Elective Percutaneous Coronary Intervention

Abstract

Background: Advances in Percutaneous Coronary Intervention (PCI) techniques have improved patient outcome. However, occurrence of myonecrosis after elective PCI has been extensively debated. Aim of Study: We investigated the value of the ratio of early transmittal velocity to tissue Doppler mitral annular early diastolic velocity (E/E') in detecting the occurrence of peri-procedural myocardial injury in patients undergoing elective PCI. Patients and Methods: Sixty two patients undergoing elective PCI were recruited prospectively. All participants had EF% >50% and sinus rhythm. E/E' ratio was measured immediately before, and within 24 hours after PCI. CK-MB and cardiac troponin (cTn) were measured in the same day after successful PCI to diagnose myocardial injury. Results: The cohort age was 56.7 ±9.7 year, and consisted of forty four (71%) males, 49 (27.4%) had ≥ two risk factors for CAD, 60% were symptomatic before PCI. Thirty (48.4%) patients had regional wall motion abnormalities (regional Wall Motion Score Index (WMSI): 0.74 ± 0.29). Myocardial injury was diagnosed by elevated cTn in 39 (62.9%) patients. Patients with predilation showed reduction of LVEDP as estimated by ∆ E/E' (8.9±2.9 Vs. 7.9±3.2, p<0.001). Pearson correlation analysis revealed that the E/E' correlated negatively with LV EF% (r=-26, p<0.03), positively with CK-MB and cTn level after PCI (r=.51, p<0.0001), NYHA functional class (r=.72, p<0.001), the number of risk factors, and number of vessel diseased and the number of vessel treated with PCI (r=36, p<0.003 all). Using ROC curve E/E' value ≥6.55 has 68.1% sensitivity and 66.6% specificity to detect myocardial injury after PCI. From all clinical and echo variables, multivariate regression analysis revealed that only E/E' and number of stents were predictors of postprocedural cardiac injury in elective PCI. Conclusion: These data suggest that the tissue Doppler derived-index of LV filling pressure (E/E') may be a useful indicator for predicting early myocardial injury after successful