[Usefulness of stress MPI for assessment of PCI indication--comparison with FFRmyo evaluation using pressure sensor wire].

PURPOSE: To examine the usefulness of percutaneous coronary intervention (PCI) indication assessment using stress myocardial perfusion imaging (St-MPI). BACKGROUND: The usefulness of myocardial fractional flow reserve (FFRmyo) using a pressure sensor wire for the assessment of PCI indication has been reported in recent years. However, we have frequently experienced discrepancies between results from FFRmyo and St-MPI. SUBJECTS AND METHODS: Forty-two patients with single-vessel disease with 75-90% (AHA classification) stenosis and chronic ischemic heart disease were enrolled in this study. We measured FFRmyo during coronary angiography (CAG), and determined that it was less than 0.75 in all cases. We separated the cases into groups based on the results of the St-MPI, which was carried out just prior to the CAG: 18 patients showing positive stress test (group P); and 24 patients showing negative stress test (group N). We selected PCI only for the group P. We tracked both groups for 4.4 +/-0.6 years and investigated the existence or non-existence of cardiac events therein. We carried out another St-MPI one year later on the group of cases without cardiac events. RESULTS: Although a fatal cardiac infarction occurred in 1 case in the group P, there were no occurrences of major cardiac events (cardiac death or fatal cardiac infarctions) in the group N. Minor cardiac events (new PCI, target lesion re-vascularization: TLR, coronary artery bypass surgery and heart failure) were detected in 8 cases (44%) in the group P and 3 cases (13%) in the group N, thus being a significantly high percentage in the group P (p<0.05). In group P patients without having restenosis at 1 year after PCI, VO2 was significantly improved as compared to that before PCI. However, no significant difference in VO2 before and after followup was observed in group N. CONCLUSION: Because the prognosis of patients with single-vessel stable ischemic heart disease is good, it can be inferred that the principal cardiac events therein are minor cardiac events. When we define minor cardiac event as endpoint, St-MPI can be a more beneficial test for the assessment of PCI indication than FFRmyo.

[Feasibility of long-term outcome prediction in acute myocardial infarction using the discordance between early and delayed image on 123I-BMIPP myocardial scintigraphy].

OBJECTIVES: The feasibility of long-term outcome prediction using BMIPP myocardial scintigraphy was evaluated in cases of acute myocardial infarction. METHODS: BMIPP myocardial scintigraphy was performed on 165 patients with first acute myocardial infarction at the time of discharge from the hospital (average of 27 days after disease on set). Discordance between early and delayed image was checked and its relation to later cardiac events (during the mean follow up period of 64.2 +/- 9.8 months) was analyzed. In 82 of these 165 cases TlCl scintigraphy was simultaneously performed (Tl/BMIPP dual SPECT) to examine mismatch form BMIPP scintigraphy and discordance between early and images. RESULTS: Discordance between early and delayed images was observed in 86 cases (52%). Among patients for whom dual SPECT was performed, mismatch between TlCl and BMIPP scintigraphy was observed in 30 cases (37%). When the relation between mismatch and discordance was analyzed, mismatch was accompanied by washout. The incidence of later cardiac events was significantly higher for cases showing discordance accompanied by washout and cases showing mismatch on dual SPECT scintigraphy than cases without these findings. When multivariate analysis was conducted, involving age, sex, infarction related artery, left ventricular end-diastolic volume index, left ventricular ejection fraction, severity of disturbed fatty acid metabolism, washout and fill-in, washout was identified as an independent predictor of cardiac events. CONCLUSION: Mismatch on Tl/BMIPP dual SPECT is important for predicting long-term prognosis of acute myocardial infarction. Furthermore, washout on BMIPP scintigraphy is also useful as a predictor of cardiac events.

[Assessment of therapeutic effect in acute myocardial infarction using early/delayed images of 123I-BMIPP myocardial scintigraphy].

This study was aimed at analyzing the discordance between the initial and late scintigraphic images in patients with acute myocardial infarction (AMI), and utilizing the data obtained for the treatment of AMI patients. Ninety-one patients with a history of the first episode of AMI were enrolled as subjects for this study. Emergency coronary angiography was performed in all the patients and left ventriculography (LVG) was carried out subsequently. 123I-BMIPP myocardial scintigraphy was performed to obtain initial images (BMi) and delayed images at 4 hours (BMd). Scintigraphy was performed a mean of 6 days after the onset of AMI in the patients. The subjects were classified into three groups according to the scintigraphic data. Quantitative gated single photon emission computed tomography (SPECT) with 99mTc-sestamibi (MIBI) was also conducted one month and 6 months later in all the patients. Discordance was observed in 51% of the patients. Left ventricular volume based on the quantitative gated SPECT (QGS) data at one month and 6 months after myocardial scintigraphy was significantly smaller in the washout group than in the other two groups. There was no significant change in LV volume measured at 6 months as compared to that measured at one month in the washout group. Significant increases in LVEDVI and LVESVI were observed over time in the no discordance group. In the fill-in group, the LV volume at one month was significantly higher than that in the washout group, but no significant change with time was observed. During the subacute stage of myocardial infarction, discordance is often seen between initial and late BMIPP-myocardial-scintigraphic images. The presence of such discordance, and analysis of its pattern, may be useful in predicting the cardiac function in these patients during the chronic phase of this disease.