Limitation of angiography to identify the culprit plaque in acute myocardial infarction with coronary total occlusion utility of coronary plaque temperature measurement to identify the culprit plaque.

OBJECTIVES: The purpose of this study was to test the hypothesis that the maximal temperature (Tmax) site, as measured by thermal wire, coincides with the culprit plaque by intravascular ultrasound (IVUS) in patients with acute myocardial infarction (AMI). BACKGROUND: Subsequent thrombosis developing to the proximal region from the site of plaque rupture or erosion can potentially complicate the ability of coronary angiography to identify the accurate culprit plaque in patients with coronary total occlusion. METHODS: In 45 consecutive patients with a first anterior AMI, the Tmax site by thermal wire and the culprit plaque by IVUS were evaluated in the left anterior descending coronary artery (LAD). RESULTS: Twenty-five patients had LAD total occlusion, and the remaining 20 had LAD reperfusion. In both groups of patients, the Tmax site was significantly more distal to the angiographically most stenotic site or occlusive site (reperfusion: mean distance [MD] = 1.1 mm distal, 95% confidence interval [CI] 0.3 to 1.9 mm, p = 0.01; total occlusion: MD = 8.8 mm distal, 95% CI 8.0 to 9.6 mm, p < 0.0001). The culprit plaques by IVUS approximately coincided with those by angiography or thermal wire in patients with reperfusion. However, the angiographic occlusive site was significantly more proximal to the culprit plaque by IVUS (MD = 9.2 mm, 95% CI 7.9 to 10.6 mm, p < 0.0001), but the Tmax site coincided with the culprit plaque by IVUS (MD = 0.3 mm distal, 95% CI 0.3 mm proximal to 1.0 mm distal, p = 0.293) in patients with total occlusion. CONCLUSIONS: Temperature measurement of coronary plaque enables accurate localization of the culprit plaque in AMI with coronary total occlusion.

Noninvasive prediction of complications with anteroseptal acute myocardial infarction by left ventricular Tei index.

BACKGROUND: Tei index has been proposed as a noninvasive and simple index that enables the evaluation of global left ventricular (LV) function and prediction of patient prognosis. However, its use to predict complications with acute myocardial infarction (AMI) is not fully investigated. Therefore, the purpose of this study was to investigate whether or not LV Tei index allows noninvasive prediction of complications with AMI. METHODS: In all, 80 consecutive patients with anteroseptal AMI were enrolled. LV Tei index was measured at the time of admission as (a - b)/ b , where a is the interval between cessation and onset of mitral filling flow and interval b is the aortic flow ejection time. Subsequent complications including cardiac death, shock, congestive heart failure, ventricular tachycardia/fibrillation, paroxysmal atrial fibrillation/flutter, advanced atrioventricular block requiring pacing, pericardial effusion, and LV aneurysm during the 30 days after the onset of AMI were prospectively evaluated and compared with the initial Tei index at admission. RESULTS: Complications developed in 31 of 80 (39%) patients with AMI. The Tei index was significantly increased for patients with complications compared with those without them (0.69 +/- 0.16 vs 0.50 +/- 0.11, P < .0001). When Tei index > or = 0.59 was used for the criteria, the sensitivity, specificity, and overall accuracy to predict subsequent complications were 77%, 86%, and 85%, respectively. CONCLUSION: In patients with anteroseptal AMI, LV Tei index at arrival to the hospital in the acute phase allows noninvasive prediction of subsequent complications.

Noninvasive estimation of impaired hemodynamics for patients with acute myocardial infarction by Tei index.

BACKGROUND: Tei index, defined as the sum of isovolumic contraction and relaxation times divided by ejection time, has been proposed to express global left ventricular function. For patients with acute myocardial infarction (AMI), left ventricular function can potentially be a major determinant of hemodynamics with limited time for compensation, such as increased brain natriuretic peptide to attenuate congestion, and usually without any intervention to modify cardiac loading on arrival at the hospital during the acute phase. We, therefore, hypothesized that left ventricular function, expressed by the Tei index, allows noninvasive estimation of impaired hemodynamics for patients with AMI. METHODS: We studied 86 consecutive patients with first AMI (34 inferoposterior and 52 anteroseptal). Tei index was obtained as: (a - b)/b, where a is the interval between the cessation and onset of mitral flow and b is the ejection time by aortic flow by pulsed Doppler echocardiography. By using pulmonary capillary wedge pressure (PCWP) > or = 18 mm Hg or <18 mm Hg and cardiac index (CI) < or = 2.2 L/min/m(2) or > 2.2 L/min/m(2) by consecutive catheterization, patients were classified into 4 subsets: subset I with normal hemodynamics; subset II with elevated PCWP; subset III with reduced CI; and subset IV with both elevated PCWP and reduced CI. RESULTS: For patients with inferoposterior AMI, there was no significant correlation between the Tei index and PCWP or CI. For patients with anteroseptal AMI, however, the Tei index showed significant correlation both with PCWP (r = 0.59, P <.0001) and CI (r = -0.42, P <.01). Diagnosis of impaired hemodynamics (subset II-IV) by a Tei index > or = 0.60 showed a sensitivity, specificity, and accuracy of 86%, 82%, and 83%, respectively. CONCLUSIONS: Although the Tei index has limitations to evaluate hemodynamics in patients with inferoposterior AMI, the index allows approximate but quick and practical noninvasive estimation of impaired hemodynamics in patients with anteroseptal AMI.

Noninvasive differentiation of pseudonormal/restrictive from normal mitral flow by Tei index: a simultaneous echocardiography-catheterization study in patients with acute anteroseptal myocardial infarction.

BACKGROUND: Differentiation of pseudonormal/restrictive from normal mitral flow is still clinically problematic. Pseudonormal/restrictive flow is usually associated with left ventricular dysfunction, which can be detected by Doppler Tei index, combining systolic and diastolic function. Therefore, the purpose of this study was to test the feasibility of the Tei index to differentiate pseudonormal/restrictive from normal mitral flow. METHODS: In 26 patients with anteroseptal acute myocardial infarction and early diastolic mitral flow velocity (E) to late diastolic mitral flow velocity (A) ratio (E/A) > or = 1, left ventricular volumes; E and A; deceleration time of E; and the Tei index, defined as the sum of the isovolumic contraction and relaxation time divided by ejection time, were evaluated by Doppler echocardiography, and pulmonary capillary wedge pressure was measured by catheterization. Pseudonormal/restrictive mitral flow was defined as E/A > or = 1 associated with pulmonary capillary wedge pressure > 12 mm Hg. RESULTS: There were 19 and 7 patients with pseudonormal/restrictive and normal mitral flow, respectively. Among the indices of left ventricular function, the Tei index achieved the best correlation with pulmonary capillary wedge pressure (r(2) = 0.66, P <.0001). By setting the Tei index > or = 0.55 as the criteria for pseudonormal/restrictive mitral flow, this diagnosis had the sensitivity, specificity, and accuracy of 84%, 100%, and 88%, respectively. CONCLUSION: The Tei index allows noninvasive differentiation of pseudonormal/restrictive from normal mitral flow.