Effect of nicorandil administration on myocardial microcirculation during primary percutaneous coronary intervention in patients with acute myocardial infarction.

INTRODUCTION: Prevention of the no-reflow phenomenon has a crucial role in primary percutaneous coronary intervention (P-PCI) procedures. AIM: To assess the effects of early intracoronary administration of nicorandil (NIC) during P-PCI on myocardial microcirculation in patients with acute myocardial infarction (AMI). MATERIAL AND METHODS: A total of 120 patients with first acute anterior wall ST segment elevation myocardial infarction who underwent P-PCI were randomly divided into two groups: the NIC group (A, n = 60) and the placebo group (B, n = 60). Before stent placement, NIC or normal saline was injected using a guiding catheter. The thrombolysis in myocardial infarction (TIMI) grade, TIMI myocardial perfusion grade (TMPG), resolution of ST segment elevation (defined as > 50% decrease in ST elevation) 1 h after surgery, and 99Tcm-methoxyisobutyl isocyanide (MIBI) rest myocardial perfusion imaging (MPI) via single-photon emission computed tomography (99Tcm-MIBI SPECT) findings 10 days after surgery were compared between the two groups. RESULTS: The number of patients who achieved TIMI grade 3 (96.67% vs. 86.67%; p = 0.047) and TMPG 3 (95% vs. 83.33%; p = 0.040) was higher in the NIC group than in the placebo group. Resolution of ST segment elevation occurred in 95% and 81.67% of the patients in the NIC and placebo groups, respectively (p = 0.023); the MPI score of the two groups was 4.1 ±1.89 and 7.3 ±2.65, respectively (p = 0.014). CONCLUSIONS: Early coronary administration of NIC can significantly reduce the damage in the myocardial microcirculation caused by P-PCI and the myocardial infarct size in patients with AMI.

Usefulness of PET/CT in the diagnosis of recurrent or metastasized differentiated thyroid carcinoma.

The aim of the present study was to determine the usefulness of the positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose (FDG) in the detection of recurrence or metastasization of differentiated thyroid carcinoma (DTC) in patients with abnormal thyroglobulin levels and negative findings on the 131I-diagnostic whole-body scanning (dWBS). Fifteen patients with DTC, abnormal thyroglobulin levels, and negative 131I-dWBS findings were scanned using the 18F-FDG PET/CT. Positive diagnosis was based on postoperative histologic findings, and clinical and imaging follow-up results obtained in the subsequent 6 months. In addition, preoperative and postoperative thyroglobulin levels were compared. Using the findings of 18F-FDG PET/CT and data on confirmed positive diagnosis, sensitivity and positive predictive value (PPV) were calculated. Sensitivity and PPV of PET/CT in detecting recurrence or metastasisization of DTC were 93.30 and 91.40%, respectively. Furthermore, postoperative thyroglobulin levels were markedly lower compared to the preoperative levels (respectively, 4.67±1.71 vs. 58.53±18.34 ng/ml; p<0.05). PET/CT scan with 18F-FDG is an informative technique for the detection of recurrent or metastasized DTC in patients with abnormal thyroglobulin levels and negative 131I-dWBS findings.

Coronary arteriography in the diagnosis results and prognosis analysis of suspected coronary artery disease in patients with normal SPET myocardial perfusion imaging.

OBJECTIVE: Anatomic coronary artery disease (CAD) can be determined by coronary angiography (CAG) in patients with normal stress single photon emission tomography (SPET) myocardial perfusion imaging (MPI). Coronary angiography results of patients with negative exercise MPI and the prognosis of these patients (CAG-diagnosed CAD vs. non-CAD) were investigated in the current study. SUBJECTS AND METHODS: Suspected CAD patients who had SPET-MPI and subsequent CAG studies were retrospectively reviewed from May 2002 to November 2006. Siemens Diacam SPET and Siemens Ecam SPET γ-cameras were used for the examination of rest/exercise technetium-99m methoxy isobutyl isonitrile ((99m)Tc-MIBI) myocardial imaging. Coronary angiography was performed with Philips arura angiography machine by the standard Judkins method. RESULTS: In all, 6598 patients underwent clinically indicated rest/exercise (99m)Tc-MIBI SPET-MPI, and 133 patients underwent CAG despite negative MPI. Thirty one patients were diagnosed with CAD by CAG. Most of these lesions (66%) were located in distal vessels and most of these patients (68%) had 1 vessel disease. Age (P<0.01), hypertension (P<0.01), typical angina pectoris (P<0.01), high pretest likelihood of CAD (P<0.001), exercise induced angina (P<0.05), positive exercise ECG (P<0.01), and transient enlargement of scintigraphic left ventricular size (P<0.05) were significantly different between non-CAD and CAD groups. After median follow-up time of 53 ± 18 months, annualized cardiac event rate was 0.9% and 0.2% in CAD and non-CAD group, respectively (χ² = 1.22, P=0.27). CONCLUSION: In all, 23% of 133 patients in our study we confirmed anatomic CAD by CAG, despite negative findings in SPET-MPI. Several clinical, stress, and MPI findings could be potential predictors. However, similar to non-CAD group, the CAG diagnosed CAD patients negative (99m)Tc-MIBI SPET-MPI exercise test had a good prognosis with annualized cardiac event rate less than 1.0%.

Assessment of Coronary Flow Reserve by Adenosine Stress Myocardial Perfusion Imaging in Patients with Hypertension.

In this study, our aim was to assess the coronary flow reserve (CFR) by performing the adenosine stress (99m)Tc-MIBI single-photon computed tomographic (SPECT) myocardial perfusion imaging in patients with hypertension. 47 hypertensive patients with normal coronary angiography were divided into 2 groups, defined by the presence (LVH, n = 22) and absence (non-LVH, n = 25) of left ventricular hypertrophy with 17 normal cases as controls. All patients were administered the adenosine stress-rest (99m)Tc-MIBI scintigraphy. 0.14 mg/kg/min adenosine was administered by continuous infusion for 6 min. We found that adenosine-induced myocardial ischemia was present in 26 cases (55.3 %) with 87 segments (20.6 %) showing abnormal distribution in the hypertensive group versus a single case (5.9 %) (χ (2) = 31.12, P < 0.001) and segment (0.7 %) (χ (2) = 32.90, P < 0.001) in the control group by SPECT perfusion. In the LVH group, 17 cases (77.3 %) and 67 segments (33.8 %) of myocardial ischemia were present. In the non-LVH group, there were 9 cases (36.0 %) (χ (2) = 8.06, P < 0.001), 20 segments (8.9 %) (χ (2) = 40.13, P < 0.001). There was a significant decrease in coronary reserve in the hypertensive groups following adenosine infusion with a fourfold decrease in cases and a sixfold decrease in segments (P < 0.001). Our study suggests that assessing CFR by the (99m)Tc-MIBI adenosine stress by SPECT imaging is a relatively easy, safe, and non-invasive test in patients with hypertension. We noted a decrease in CFR in patients with hypertension. This decrease was especially remarkable for hypertensive patients with LVH. This study shows that administering the (99m)Tc-MIBI adenosine stress by SPECT imaging is a safe, simple, and non-invasive test for detecting CFR in patients with hypertension.