It is concluded that the EP(10-50 Hz%) revealed the specific characteristics of RPP and significantly varied at the six positions, and the left Chun position, the position to detect the heart diseases in Chinese medicine, is qualified to discriminate the differences between the normotensive and hypertensive patients.

SUMMARYIncreased lung uptake of and technetium-99m (Tc-99m) MIBI in myocardial perfusion imaging is a reliable marker of left ventricular dysfunction. The goal of our study was to establish whether the lung-to-heart (L/H) uptake ratio with a newer cardiac imaging agent, Tc-99m tetrofosmin, can also provide valuable information about left ventricular function.We studied 60 patients with recent coronary artery diseases (CAD) undergoing firstpass radionuclide ventriculography to calculate left ventricular ejection fraction (LVEF) and myocardial perfusion imaging to calculate the L/H ratio. Group A consisting of 30 CAD patients with higher LVEF (≥40%) had a significanly lower L/H ratio than group B consisting of 30 CAD patients with abnormal LVEF (<40%) during exercise and rest. In groups A and B, the exercise and rest L/H ratios did not differ significantly. However, a statistically significant inverse correlation was found between the L/H ratio and LVEF during exercise and rest among the 60 patients.L/H ratios, measured by 99mTc-tetrofosmin imaging, provide clinically useful information with which to predict left ventricular dysfunction in CAD patients. (Jpn Heart J 2002; 43: 515-522)

Despite similar guidance by local electrogram criteria, catheter ablation of right-sided accessory atrioventricular (AV) pathways by radiofrequency current has been less effective than that of left-sided ones. In order to elucidate the possible diversities in local electrosignal criteria, we systematically analyzed the morphological and timing characteristics of 215 bipolar local electrograms from catheter ablation sites of 65 left-sided accessory AV pathways and of 356 from those of 37 right-sided ones in 92 consecutive patients with Wolff-Parkinson-White syndrome or AV reentrant tachycardia incorporating concealed accessory AV pathways. After stepwise multivariate analysis, we selected the presence of a possible accessory pathway potential, local ventricular activation preceding QRS complex for 20 ms or more during ventricular insertion mapping, and the local retrograde ventriculoatrial (VA) continuity, local retrograde VA interval ≤ 50 ms, electrogram stability (left-sided targets only), retrograde accessory pathway potential (right-sided targets only) during atrial insertion mapping, as independent local electrogram predictors for successful ablation of left- and right-sided accessory AV pathways. Combination of all local electrogram predictors could have moderate chance of success (80 and 51 %) for the ventricular and atrial insertion ablation of left-sided accessory AV pathways, but only low probability of success (40% in ventricular insertion ablation) or very low sensitivity (12.5% in atrial insertion ablation) for right-sided ones. In conclusion, with the present approach, successful catheter ablation of right-sided accessory AV pathways, compared to left-sided ones, still necessitate a breakthrough in the precision mapping and the efficiency of energy delivery.

To determine the influence of smoking on lung uptake of technetium-99m tetrofosmin (Tc-TF) during myocardial perfusion imaging, we examined 50 healthy subjects with normal myocardial perfusion single photon emission computed tomography findings, normal coronary angiograms, and no evidence of left ventricular hypertrophy. The 50 healthy subjects were divided into two groups. Group 1: 25 healthy subjects had smoking histories of at least 10 pack-years. Group 2: 25 healthy subjects were nonsmokers. Lung to heart ratios (L/H ratios) calculated from anterior planar images during exercise and rest states of Tc-TF myocardial perfusion imaging were obtained for all of the 50 healthy subjects. L/H ratios calculated from Tc-TF myocardial perfusion imaging in smokers were significantly higher than in nonsmokers during both exercise and rest states. However, no significant difference in L/H ratios was found between exercise and rest states in smokers and nonsmokers. In addition, a positive but nonsignificant correlation was found between smoking pack-years and either rest or exercise L/H ratios. When L/H ratios are used as a clinical diagnostic tool in Tc-TF myocardial perfusion imaging, we must consider that L/H ratios in smokers are higher than in nonsmokers.

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