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ultislice computed tomography (MSCT) enables visualization of not only coronary artery stenoses and occlusions, 1-4 but also coronary artery plaque of various textures. [5][6][7][8][9][10][11][12] Previous studies have repeatedly shown that non-calcified, CT low-dense plaques (CTLDP) on MSCT correspond well to rupture-prone soft plaques on intracoronary ultrasound 5,6,9,10,12 and on coronary angioscopy. 9 We have shown that patients with acute coronary syndrome (ACS) are likely to have CTLDP and that the CT density of the culprit coronary artery lesion is significantly lower in patients with ACS as compared with that in patients with stable angina. 8 Furthermore, we have also shown that patients with evolving ACS consistently have CTLDP in their culprit coronary artery lesions. 7,13 Because ACS is a consequence of coronary artery plaque rupture and subsequent thrombosis, 14,15 it would be reasonable to speculate that patients who have CTLDP are more likely to have coronary events, including ACS and sudden cardiac death, than patients without plaque. In this study of a large population, we evaluated the prognostic value of non-obstructive CTLDP in mild to moderate coronary artery stenosis for future cardiac events. Methods Study PopulationWe identified 1,179 consecutive patients who underwent MSCT between August 2002 and July 2006, at Nihon University Hospital. The reasons for MSCT were evaluation of typical and atypical chest pain in 715 patients, evaluation of the post-coronary intervention status in 112 patients, and evaluation of coronary artery disease (CAD) in 182 asymptomatic patients with multiple coronary risk factors. A structured interview and clinical history were obtained, and the following cardiac risk factors were assessed prior to the MSCT study: (1) hypertension (defined as blood pressure ≥140/90 mmHg or the use of antihypertensive agents), (2) hyperlipidemia as defined by low-density lipoprotein-cholesterol >140 mg/dl, (3) diabetes mellitus (defined as fasting glucose level >120 mg/dl or the need for insulin or oral antidiabetic medicines), (4) smoking (defined as current or previous smoking), and (5) previous history of acute myocardial infarction (AMI) and unstable angina (UA), and (4). Exclusion criteria for MSCT scans were known allergy to iodine, arrhythmias, impaired renal function (serum creatinine ≥1.3 mg/dl), bronchial asthma and left ventricular failure (left ventricular ejection fraction <30%). MSCT ProtocolMSCT was performed using either a SOMATOM Volume Background The prognostic value of non-obstructive, CT low-dense plaques (CTLDP) on multislice computed tomography (MSCT) for the prediction of nonfatal acute myocardial infarction (AMI), unstable angina (UA) and cardiac death has not yet been defined. Methods and ResultsIn the present study 810 patients who underwent MSCT and had non-obstructive coronary artery disease were followed up for the occurrence of AMI, UA and cardiac death. Non-obstructive CTLDP were defined as plaques with a CT density <68 Hounsfield units, accompanied by...

The PV-LA voltage on the PV-encircling ablation line and FTI/PV-LA voltage were related to the acute post-PVI PV reconnections. A more durable ablation strategy is warranted for high-voltage zones.

rolonged regional myocardial dysfunction following exercise-induced ischemia has been identified as a sensitive marker of ischemia in both an experimental model 1 and patients with known coronary artery disease (CAD). [1][2][3][4] Nevertheless, the correlation between a wall motion abnormality detected by ECG-gated single-photon emission computed tomography (SPECT) and the angiographic data has not been fully evaluated. ECG-gated SPECT provides information on global as well as regional systolic function, 5,6 in addition to regional myocardial perfusion. Because a regional wall motion (RWM) abnormality may persist for 30-240 min following exercise, 5 ECG-gated SPECT, acquired within 60 min after exercise cessation, has the potential to detect post-stress RWM abnormality in patients with multivessel CAD and highgrade coronary artery stenosis in the proximal coronary artery segments. 7-9 However, the value of wall motion analysis using ECG-gated SPECT in patients with mild, single-vessel CAD has not yet been evaluated and because Circulation Journal Vol.69, March 2005a RWM abnormality is most apparent in the early phase of the post-exercise period, we speculated that wall motion analysis shortly after exercise might give incremental diagnostic value to myocardial perfusion SPECT in patients with mild, single-vessel CAD. Methods Patient PopulationThe study group consisted of 97 normal subjects (Group 1: 57 men, 42 women; age 60±11 years) and 46 patients with angiographically documented single-vessel CAD (Group 2: 40 men, 6 women; age 61±9 years) who underwent separate acquisition, dual isotope ECG-gated SPECT. Group 1 consisted of patients with atypical chest pain who were classified as having a low likelihood of CAD according to the American Heart Association/American Colledge of Cardiology classification for assessment of cardiovascular risk using multiple-risk-factor assessment equations. 10 In all the patients of Group 1, coronary CT angiography was performed using a Siemens SOMATOM Volume Zoon with the image reconstruction method developed in our laboratory 11 and it revealed no significant coronary artery stenosis in their major coronary arteries. The diagnostic accuracy of coronary CT angiography in comparison with invasive coronary angiography has been proved to be excellent, with a sensitivity of 94% and specificity of 97% Circ J 2005; 69: 301 -305

BackgroundAlthough clinical trials have proved that statin can be used prophylactically against cardiovascular events, the direct effects of statin on plaque development are not well understood. We generated low‐density lipoprotein receptor knockout (LDLR −/−) pigs to study the effects of early statin administration on development of atherosclerotic plaques, especially advanced plaques.Methods and Results LDLR −/− pigs were generated by targeted deletion of exon 4 of the LDLR gene. Given a standard chow diet, LDLR −/− pigs showed atherosclerotic lesions starting at 6 months of age. When 3‐month‐old LDLR −/− pigs were fed a high‐cholesterol, high‐fat (HCHF) diet for 4 months (HCHF group), human‐like advanced coronary plaques developed. We also fed 3‐month‐old LDLR −/− pigs an HCHF diet with pitavastatin for 4 months (Statin Prophylaxis Group). Although serum cholesterol concentrations did not differ significantly between the 2 groups, intravascular ultrasound revealed 52% reduced plaque volume in statin‐treated pigs. Pathological examination revealed most lesions (87%) in the statin prophylaxis group were early‐stage lesions, versus 45% in the HCHF diet group (P<0.01). Thin‐cap fibroatheroma characterized 40% of the plaques in the HCHF diet group versus 8% in the statin prophylaxis group (P<0.01), intraplaque hemorrhage characterized 11% versus 1% (P<0.01), and calcification characterized 22% versus 1% (P<0.01).ConclusionsResults of our large animal experiment support statin prophylaxis before the occurrence of atherosclerosis. Early statin treatment appears to retard development of coronary artery atherosclerosis and ensure lesion stability. In addition, the LDLR −/− pigs we developed represent a large animal model of human‐like advanced coronary plaque suitable for translational research.

Myocardial perfusion SPECT can contribute to the prediction of cardiac events and survival in patients at all stages of CKD including those on hemodialysis.

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MPI would be useful to stratify patients with advanced conservative CKD who are at high risk of cardiac events without adversely affecting damaged kidneys.