心血管疾患と診断

Background: The effect of the different sites of acute ST-elevation myocardial infarction (STEMI) and left ventricular (LV) dysfunction on systolic and diastolic right ventricular (RV) function is still unclear. In this study, we aimed to assess the effect of primary percutaneous coronary intervention (PPCI) on RV function using echocardiography.

Methods: One hundred and seven consecutive patients with first episode of acute STEMI were enrolled in this study with echocardiographic imaging obtained both within 24 hours and 6 months after successful PPCI. Patients were divided into two groups, anterior (45%) and non-anterior STEMI (55%) based on significant ST-segment elevation.

Results: At presentation, TAPSE (tricuspid annular plane systolic excursion) and FAC (Fractional area change) were significantly lower in nonanterior vs. anterior group (1.9 ± 0.44 vs. 1.57 ± 0.47cm, p=0.005), (40.4 ± 7.5 vs. 34.6 ± 9%, p=0.001). No significant differences of tricuspid E/A, E/é ratio between both groups were detected while a negative correlation between LV-EF (ejection fraction) and TAPSE was recorded (r=0.24). At follow up, the anterior group showed significant improvement of RV-MPI (myocardial performance index) and LV-EF (p value=< 0.01 and 0.08, consecutively) but not of RV-DF (diastolic function). In non-anterior group, RV recovered significantly regarding FAC, TAPSE, RV-MPI and tricuspid E/é (p value=< 0.01 for all) with no improvement of LV-DF or LV-EF irrelevant of the infarction site. LV-EF showed negative correlation with LV-DF at baseline (r=0.22) and follow up (r=0.4), and with tricuspid E/é at follow up (r=0.4). Additionally, positive correlation between LV-DF and both tricuspid E/é and grades of mitral regurgitation (MR) at baseline and follow up (r=0.37, 0.28 respectively).

Conclusion: RV dysfunction can be detected in both anterior and non-anterior STEMI patients at presentation which is more prominent in the nonanterior group. At follow up successful primary PCI patients exhibited recovery of RV systolic function in both groups, while impairment of LV-DF was noted irrelevant of the infarction site. Assessment of RV systolic and diastolic function using echocardiography is useful, rapid and feasible method that can be done initially and at follow up to all STEMI patients.

European Society of Cardiology (ESC) 0/3-h algorithm using high sensitivity cardiac troponin (hs-troponin) is recommended to detect acute myocardial infarction (MI) for patients with acute chest pain. As hs-troponin may be less specific, we assessed the usefulness of coronary computed tomography angiography (CCTA) in addition to standard care for patients with acute chest pain. We investigated 695 patients who visited the emergency department for acute chest pain and performed serial hs-troponin T and CCTA. Obstructive coronary artery disease (CAD) on CCTA was defined as >=50% stenosis. The primary outcome was the occurrence of MI within 30 days. According to ESC 0/3-h algorithm, patients were categorized into rule-out (425, 61.2%), rule-in (155, 22.3%), and observe group (115, 16.5%). Eighty-one patients (11.7%) were diagnosed with MI. Two hundred ten patients had obstructive CAD on CCTA. The addition of obstructive CAD on CCTA to ESC 0/3-h algorithm improved the diagnostic accuracy for MI (area under the curve: from 0.85 to 0.911, p=0.003). Even for the rule-in and rule-out patients, the specificity (from 78.9% to 94.5%) and positive predictive value (from 32.1% to 62.8%) were significantly improved after the addition of CCTA to ESC 0/3-h algorithm. Half of the patients in the rule-in group did not undergo invasive coronary angiography based on CCTA findings without further MI events. CCTA added to the serial hs-troponin may improve the prediction of MI in patients with acute chest pain.