Sonographically Measured Adipose Tissue Thickness Correlates with Laboratory Test Abnormalities Reflecting Metabolic State in Elderly Women.

Background: Accumulation of adipose tissue progresses to metabolic diseases. Sonography is a convenient modality for measuring the thickness of adipose tissue. The present study aimed to clarify the site of adipose tissue thickness that correlated best with laboratory test values reflecting metabolic abnormalities. Methods: Subjects comprised 37 elderly women with metabolic diseases or an almost healthy state (median age, 71 years; interquartile range, 62-78 years). Abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue, peritoneal adipose tissue, perirenal adipose tissue, and epicardial adipose tissue (EAT) thicknesses were measured. Correlations were evaluated between laboratory test values and these adipose tissue thicknesses. Results: VAT thickness measured at the level of the umbilicus correlated positively with values of triglycerides (TGs) (r = 0.593, P = 0.0009) and hemoglobin A1c (r = 0.490, P = 0.0081) and negatively with the value of high-density lipoprotein cholesterol (r = -0.521, P = 0.0045), even after adjusting for body mass index. Significant positive correlations were also found between EAT thickness and TGs (r = 0.542, P = 0.0029). Conclusions: Among the adipose tissue thicknesses measured at several sites by sonography, VAT thickness correlated most closely with laboratory test values representing metabolic abnormalities in elderly women.

Relationship between Pericardial Adipose Tissue Thickness and Early Impairment of Left Ventricular Function, Both Evaluated on Echocardiography.

Epicardial adipose tissue (EAT) is metabolically bioactive, and accumulation of this tissue is related to early impairment of left ventricular (LV) systolic function as well as diastolic function. However, pericardial adi- pose tissue (PAT), located outside the EAT, has recently been demonstrated to be more closely associated with metabolic risk factors than EAT. The present study aimed to clarify whether PAT thickness is related to early impairment of LV function in a similar manner to EAT thickness, with both evaluated echocardio- graphically. Subjects were 49 women (mean age, 68ill years) composed of both patients with metabolic diseases and those with other diseases, and ejection fraction (EF) >55%. Systolic function was assessed by measuring EF, systolic mitral annular velocity (S'), and tissue mitral annular displacement percentage (TMAD%). Diastolic function was assessed by measuring early rapid filling wave velocity (E)/late filling wave velocity due to atrial contraction (A) ratio (E/A), peak early diastolic mitral annular velocity (e'), and E/e' ratio. Correlations between EAT or PAT thickness and LV systolic or diastolic function were assessed. EAT thickness correlated with S' and TMAD%(r=-0.399, p=0.005 and r=-0.570, p<0.001, respective- ly), but not with EF. However, PAT thickness was not correlated with any of these. EAT thickness corre- lated with E/A, e' and E/e'(r=-0.382, p=0.007; r=-0.493, p<0.001; and r=0.331, p=0.020, respective- ly). Again, PAT thickness was not correlated with any of these. PAT thickness appears unrelated to early impairment of LV function.

Usefulness of P-wave dispersion in standard twelve-lead electrocardiography to predict transition from paroxysmal to persistent atrial fibrillation.

A prospective study was conducted to investigate the validity of the hypothesis that P-wave dispersion (Pd) may be a clinically useful predictor of progression from paroxysmal to persistent atrial fibrillation (AF). Two hundred four consecutive patients with a diagnosis of paroxysmal AF were studied. Standard 12-lead electrocardiography and echocardiography were performed on all patients at the time of entry into the study. Pd was measured as the difference between maximum and minimum P-wave duration in any of the 12 leads. Mean follow-up was 66 +/- 8 months. Group I included patients (n = 132) in whom paroxysmal AF did not progress to persistent AF, and group II included those (n = 72) who developed persistent AF. In group II, age, percentage of men, percentage of patients with diabetes mellitus, maximum P-wave duration, Pd, and left atrial dimension were significantly higher than in group I (p <0.05). Multivariate logistic regression analysis using these 6 factors identified age (odds ratio 2.18, 95% confidence interval 1.41 to 3.41, p <0.01) and Pd (odds ratio 1.91, 95% confidence interval 1.51 to 2.44, p <0.01) as independent predictors of a transition to persistent AF. Pd >or=40 ms predicted progression to persistent AF with sensitivity of 71%, specificity of 77%, positive predictive value of 63%, negative predictive value of 83%, and accuracy of 75%. In conclusion, Pd was a clinically useful predictor of progression from paroxysmal to persistent AF.

The full stomach test as a novel diagnostic technique for identifying patients at risk of Brugada syndrome.

INTRODUCTION: Autonomic modulation, particularly high vagal tone, plays an important role in the occurrence of ventricular tachyarrhythmias in the Brugada syndrome. Food intake modulates vagal activity. We assessed the usefulness of a novel diagnostic technique, the "full stomach test," for identifying a high-risk group in patients with a Brugada-type electrocardiogram (ECG). METHODS AND RESULTS: In 35 patients with a Brugada-type ECG, we assessed 12-lead ECGs before and after a large meal, a pilsicainide pharmacological test, spontaneous ST-segment change, late potentials by signal-averaged ECG, microvolt T-wave alternans, and four other ECG parameters. These patients were divided into two groups (i.e., high-risk group [n = 17] and indeterminate risk group [n = 18]). The full stomach test was defined as positive when augmentation of characteristic ECG abnormalities was observed after meals. Thirteen patients had a prior history of life-threatening events such as aborted sudden death and syncope, with a total of 30 episodes. These episodes had a circadian pattern, at night and after meals. The full stomach test was positive in 17 of the study patients (49%). A positive test outcome was characterized by a higher incidence of a history of life-threatening events than a negative test outcome (P = 0.015, odds ratio = 7.1). In comparison between the two groups, the incidence (82%) of positive outcomes in the high-risk group was significantly higher than that (17%) in the indeterminate risk group (P = 0.0002). CONCLUSIONS: Characteristic ECG changes diagnostic of Brugada syndrome are augmented by a large meal. These data are associated with a history of life-threatening events in Brugada syndrome.

A new application of the ST-HR loop to evaluate the exercise-induced reversible ischemia in healed anterior wall myocardial infarction.

Exercise-induced ST-segment elevation in infarct-related leads is often seen on the treadmill exercise electrocardiogram of patients with anterior wall myocardial infarction. However, the cause of this phenomenon is still a matter of controversy. The purpose of this study was to evaluate the relation between the direction of ST-segment-heart rate (ST-HR) loop rotation and reversible myocardial ischemia in the infarct-related area. A total of 58 patients were enrolled in this study. They had healed anterior wall myocardial infarctions with single-vessel coronary artery disease and exercise-induced ST-segment elevations in the infarct-related leads, as observed on treadmill exercise electrocardiograms. All patients underwent treadmill exercise electrocardiography and dobutamine stress echocardiography at discharge. The direction of rotation of the ST-HR loop constructed from the treadmill exercise electrocardiogram and the dobutamine stress echocardiographic findings in the infarct-related area were compared. Counterclockwise rotation was seen in 26 of 58 patients. Compared with clockwise rotation, patients with counterclockwise rotation had significantly more viable myocardium (92% vs 69%, p = 0.04) and presence of reversible myocardial ischemia (58% vs 6%, p < 0.01). On the basis of the counterclockwise rotation findings, the diagnostic value of the presence of reversible myocardial ischemia was calculated. The sensitivity, specificity, and accuracy was 88%, 73%, and 77%, respectively. Counterclockwise rotation of ST-HR loops was strongly related to reversible myocardial ischemia in the infarct-related area. In conclusion, our results have shown that analysis of ST-HR loops may be useful in evaluating the cause of exercise-induced ST-segment elevation in infarct-related leads.

Investigation of the predictors of transition to persistent atrial fibrillation in patients with paroxysmal atrial fibrillation.

BACKGROUND: Until now, no clinically useful indicators have existed that predict the transition from paroxysmal to persistent atrial fibrillation (AF). HYPOTHESIS: The current prospective study was conducted for identifying predictors of progression to persistent AF over the long term. METHODS: We studied 102 consecutive patients (mean age: 55 +/- 10 years: 75 men and 27 women) diagnosed with paroxysmal AF. Standard 12-lead electrocardiography, echocardiography, and P-wave-triggered signal-averaged electrocardiography (P-SAECG) were performed on all patients at the time of their entry into the study. RESULTS: The mean follow-up period was 61 +/- 13 months. Group 1 (n = 66) comprised patients in whom paroxysmal AF did not progress to persistent AF, and Group 2 (n = 36) comprised those who developed persistent AF. In Group 2 the patients were significantly older, and P-wave dispersion, filtered P-wave duration (FPD), and left atrial dimension were significantly higher than in Group 1 (p < 0.05). The root mean square voltage for the last 30 ms of the filtered P-wave was also significantly lower in Group 2 (p < 0.05). Multivariate logistic regression analysis using these five factors identified left atrial dimension (odds ratio [OR] 2.29; 95% confidence interval [CI] 1.16-4.54; p = 0.02) and FPD (OR 2.71; 95% CI 1.78-4.13; p < 0.01) as independent predictors of transition to persistent AF. Left atrial dimension > or = 40 mm predicted progression to persistent AF with a sensitivity of 64%, specificity of 76%, positive predictive value of 59%, negative predictive value of 79%, and an accuracy of 71%. An FPD > or = 150 ms predicted persistent AF with a sensitivity of 81%, specificity of 91%, positive predictive value of 88%, negative predictive value of 90%, and an accuracy of 87%. Filtered P-wave duration was a significantly more sensitive and specific predictor than left atrial dimension (p < 0.05). CONCLUSION: We conclude that FPD is a clinically useful predictor of progression from paroxysmal to persistent AF over the long term.