Impact of Prolonged Door-to-Balloon Times on the Diastolic Function in Acute ST-Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention

Background: Emerging evidence indicates that diastolic left ventricular (LV) function is a powerful outcome predictor after acute ST-elevation myocardial infarction (STEMI). We hypothesized that shorter door-to-balloon (D2B) times with early restoration of coronary perfusion may preserve diastolic LV function in STEMI patients undergoing primary percutaneous coronary intervention (PPCI). Methods: This study enrolled 340 consecutive STEMI patients who underwent PPCI with D2B times of ＜ 90 min in 232 patients and D2B times 90 min in 108 patients, who all received subsequent echocardiographic examination within 48 hours of hospitalization. Results: Although the LV ejection fraction was similar (50.92% vs. 51.66%, p = 0.573), the proportion of E/E' ratio ＞ 15 was greater in patients with D2B times ＜ 90 min compared to those with D2B times ＜ 90min (44.4% vs. 30.6%, p = 0.013). Logistic regression analysis revealed that D2B time ≥ 90 min [odds ratio (OR): 1.82, 95% confidence interval (Cl): 1.04-3.17, p = 0.035] was an independent predictor for LV diastolic dysfunction. The effect was more prominent in patients ≥ 65 years of age (OR: 2.77, 95% CI: 1.09-7.00, p = 0.032), in whom the fraction of LV diastolic dysfunction increased proportionally with prolonged D2B times. Conclusions: Prolonged D2B time of greater than 90 min predicted LV diastolic dysfunction, particularly in aged subjects. D2B times shortening is important to preserve diastolic heart function after PPCI.