The Clinical Value of Nongated Dual-Source Computed Tomography in Atrial Fibrillation Catheter Ablation.

INTRODUCTION: Using a high-pitch dual-source CT (DSCT), we aimed to quantify the amounts of contrast media, radiation doses, and image qualities in patients undergoing pulmonary vein (PV) isolation. METHODS AND RESULTS: The study enrolled 60 patients who were randomly assigned in a 1: 1: 1 ratio to undergo ECG-gated 64-slice multidetector computed tomography (MDCT; group I, n = 20), ECG-gated 128-DSCT (group II, n = 20), and nongated 128-DSCT (group III, n = 20). The total amount of contrast media was lower in groups II and III compared with group I (I: 54.7 ± 5.6, II: 26.6 ± 2.7, and III: 28.7 ± 6.9 mL, P < 0.001). The CT dose index was lower in groups II and III compared with group I (I: 73.1 ± 5.2, II: 3.5 ± 0.1, and III: 3.7 ± 0.1 mGy, P < 0.001). The dose length product was lower in groups II and III compared with group I (I: 1154.8 ± 82.8, II: 75.4 ± 2.3, and III: 77.2 ± 1.9 mGy × cm, P < 0.001). The total CT effective radiation dose was lower in groups II and III compared with group I (I: 16.2 ± 1.2, II: 1.1 ± 0.1, and III: 1.1 ± 0.1 mSv, P < 0.001). The total CT scan duration was shorter in group III compared with groups I and II (I: 30.8 ± 2.2, II: 23.4 ± 3.6, and III: 16.0 ± 2.4 minutes, P < 0.001). There were no significant differences in quality for integrated electroanatomical mapping (EAM) and parameters associated with PV isolation among the 3 groups. CONCLUSION: Nongated 128-DSCT provides sufficient image quality to allow integrated EAM while exposing the patient to less contrast media, lower radiation doses, and shorter CT scan durations.

Assessment of aortic arch stiffness using pulse-wave tissue Doppler imaging: a transesophageal echocardiographic comparison study of acute ischemic stroke patients and stroke-free patients.

BACKGROUND: Elevated aortic stiffness determined by transesophageal echocardiography (TEE), and presence of complicated aortic plaque provide prognostic information about cerebrovascular disease risk. Recently, pulse-wave tissue Doppler imaging (PW-TDI) has offered a new technique for assessing aortic wall stiffness. METHODS: The following aortic long-axis view TEE measurements were carried out in 103 consecutive acute ischemic stroke patients and 72 controls (stroke-free patients requiring TEE for conditions such as atrial fibrillation and valvular heart disease): (a) PW-TDI motion velocities measured as expansion peak velocity during systole (Vs) and contraction peak velocity during diastole (Vd); (b) aortic arch stiffness parameter ß (Aoß), defined as ß = ln (systolic blood pressure/diastolic blood pressure)/([Dmax - Dmin]/Dmin), where ln is the natural logarithm, Dmax is maximum aortic lumen diameter, and Dmin is minimum aortic lumen diameter. The PW-TDI of Vs and Vd was compared with conventional vessel parameters brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI, calculated from blood pressure and PWV). RESULTS: Comparing acute ischemic stroke patients versus controls, Vs and Vd were significantly decreased (3.3 ± 1.6 vs. 3.9 ± 2.0 cm/sec, P < 0.05; 1.7 ± 0.6 vs. 2.1 ± 0.8 cm/sec, P < 0.01, respectively), and Aoß and aortic arch intima-media thickness (AoIMT) were significantly increased (15.3 ± 12.5 vs. 11.6 ± 6.5, P < 0.05; 3.2 ± 2.5 vs. 2.4 ± 2.1 mm, P < 0.05; respectively). Furthermore, Vs and Vd were significantly negatively correlated with age, Aoß, AoIMT, CAVI, and baPWV in all cases. CONCLUSIONS: The use of aortic arch wall PW-TDI for Vs and Vd evaluation constitutes an easily and readily assessed parameter for evaluating aortic arch stiffness.

Rosuvastatin improves plaque morphology in cerebral embolism patients with normal low-density lipoprotein and severe aortic arch plaque.

The effect of rosuvastatin was investigated on complicated aortic arch plaque (CAP) morphology and lipid profiles in acute cerebral embolism (CE) patients with normal low-density lipoprotein-cholesterol (LDL-c) levels. Transesophageal echocardiography (TEE) studies were performed in 56 consecutive CE patients with LDL-c less than 140 mg/dL who were not taking lipid-lowering agents at baseline. CAP observed by TEE was defined as the presence of greater than 4-mm diameter, ulcerated, or mobile aortic plaque. Patients were divided into those with CAP versus without CAP (group A, n=24, age 69±8 years) and without CAP (group B, n=32, age 62±10 years). Of the 24 group A patients, 18 received 5 mg/d of rosuvastatin for 6 months and had follow-up TEE studies. In Group A, the baseline values of high-density lipoprotein-cholesterol (HDL-c) and apolipoprotein A-1 (ApoA-1) were significantly lower than in Group B (44±15 versus 55±15 mg/dL, P=.0059; 103±19 versus 137±25 mg/dL, P=.0006, respectively) and age and serum high-sensitivity C-reactive protein concentration were significantly higher (69±8 vs. 62±10 years, P=.0080; 2.34±3.05 vs. 0.67±1.00 mg/dL, P=.0054, respectively). By multivariate logistic regression analysis, ApoA-1 was shown to be an independent predictor of CAP (odds ratio=.894, 95% confidence intervals .800-.996, P=.0483). In the 18 group A patients receiving rosuvastatin for 6 months, aortic arch plaque diameter and serum LDL-c were significantly decreased (5.8±2.2 to 5.1±2.1 mm, P=.0377; 110±23 to 81±23 mg/dL, P=.0008, respectively), whereas serum HDL-c and ApoA-1 concentrations were significantly increased (42±8 to 52±9 mg/dL, P=.0002; 109±22 to 135±15 mg/dL, P=.0002, respectively). Plaques were morphologically improved in 11 patients, unchanged in 6, and worsened in 1. These data suggest that rosuvastatin improves plaque morphology concomitant with improving lipid profiles in CE patients with normal LDL-c levels.

Left atrial appendage dysfunction in acute cerebral embolism patients with sinus rhythm: correlation with pulse wave tissue Doppler imaging.

To evaluate left atrial appendage (LAA) dysfunction using left atrial pulse-wave tissue Doppler imaging (PW-TDI) in acute cerebral embolism (ACE) patients with sinus rhythm (SR), transthoracic (TTE) and transesophageal echocardiograhy (TEE) were performed in 60 consecutive patients with SR without obvious left ventricular dysfunction within 2 weeks after ACE. Two groups were identified: LAA dysfunction [LAA emptying peak flow velocity (LAA-eV) <0.55 m/s, n = 20, age 65 ± 10 years] and without LAA dysfunction (LAA-eV ≥ 0.55 m/s, n = 40, age 64 ± 10 years) on TEE. Left atrial wall motion velocity (WMV) was obtained from PW-TDI, with the sample volume placed at the left atrial anterior wall adjacent to ascending aortic inferior wall from the long axis view on TTE. WMVs showed triphasic waves: after the P wave (La') during systole (Ls'), and during early diastole. La' and Ls' were significantly lower in the group with versus without LAA dysfunction (4.9 ± 1.4 vs. 7.7 ± 1.8 cm/s, p < 0.0001; 5.3 ± 2.0 vs. 6.7 ± 1.9 cm/s, p < 0.001, respectively) and prevalence of paroxysmal atrial fibrillation, left atrial volume index, and serum levels of brain natriuretic peptide were significantly higher (60 vs. 15 %, p < 0.001; 32 ± 13 vs. 24 ± 13 ml/m(2), p < 0.05; 174 ± 279 vs. 48 ± 68 pg/ml, p < 0.01, respectively). La' was an independent predictor of LAA dysfunction (OR 0.380, 95 % CI 0.156-0.925, p < 0.05), and was significantly correlated with LAA-eV (r = 0.594, p < 0.0001) and LAA fractional area change (r = 0.682, p < 0.0001). The optimal cut-off value for LAA-eV < 0.55 m/s was 5.5 cm/s (sensitivity 83 %, specificity 88 %). La' is a useful and convenient strong predictor of LAA dysfunction in ACE patients with SR.

Impact of insulin resistance on silent and ongoing myocardial damage in normal subjects: the Takahata study.

BACKGROUND: Insulin resistance (IR) is part of the metabolic syndrome (Mets) that develops after lifestyle changes and obesity. Although the association between Mets and myocardial injury is well known, the effect of IR on myocardial damage remains unclear. METHODS AND RESULTS: We studied 2200 normal subjects who participated in a community-based health check in the town of Takahata in northern Japan. The presence of IR was assessed by homeostasis model assessment ratio, and the serum level of heart-type fatty acid binding protein (H-FABP) was measured as a maker of silent and ongoing myocardial damage. H-FABP levels were significantly higher in subjects with IR and Mets than in those without metabolic disorder regardless of gender. Multivariate logistic analysis showed that the presence of IR was independently associated with latent myocardial damage (odds ratio: 1.574, 95% confidence interval 1.1-2.3) similar to the presence of Mets. CONCLUSIONS: In a screening of healthy subjects, IR and Mets were similarly related to higher H-FABP levels, suggesting that there may be an asymptomatic population in the early stages of metabolic disorder that is exposed to myocardial damage and might be susceptible to silent heart failure.