Relationship of ischemic times and left atrial volume and function in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention.

Little is known about the impact of duration of ischemia on left atrial (LA) volumes and function during acute phase of myocardial infarction. We investigated the relationship of ischemic times, echocardiographic indices of diastolic function and LA volumes in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). A total of 433 consecutive STEMI patients underwent echocardiographic examination within 48 h of primary PCI, including the measurement of LA volumes and the ratio of mitral peak velocity of early filling to early diastolic mitral annular velocity (E/e'). Time intervals from onset of chest pain to hospital admission and reperfusion were collected and magnitude of Troponin I release was used to assess infarct size. Patients with LA volume index (LAVI) ≥28 ml/m(2) had longer total ischemic time (410 ± 347 vs. 303 ± 314 min, p = 0.007) and higher E/e' ratio (15 ± 5 vs. 10 ± 3, p < 0.001) than those with LAVI <28 ml/m(2), while the indices of LA function were similar between the study groups (p > 0.05, for all). Significant correlation was found between E/e' and LA volumes at all stages of LA filling and contraction (r = 0.363-0.434; p < 0.001, for all) while total ischemic time along with E/e' and restrictive filling pattern remained independent predictor of LA enlargement. Increased LA volume is associated with longer ischemic times and may be a sensitive marker of increased left ventricular filling pressures in STEMI patients treated with primary PCI.