Improvement of Left Ventricular Function by Permanent Direct His-Bundle Pacing in a Case with Dilated Cardiomyopathy

The patient was a 67-year-old female diagnosed with dilated cardiomyopathy. She had chronic atrial fibrillation (AF) with bradycardia and low left ventricular function (left ventricular ejection fraction (LVEF) 40%). She was admitted for congestive heart failure. She remained New York Heart Association (NYHA) functional class III due to AF bradycardia. Pacemaker implantation was necessary for treatment of heart failure and administration of dose intensive β-blockers. As she had normal His-Purkinje activation, we examined the optimal pacing sites. Hemodynamics of His-bundle pacing and biventricular pacing were compared. Pulmonary capillary wedge pressure (PCWP) was significantly lower on Hisbundle pacing than right ventricular (RV) apical pacing and biventricular pacing (13mmHg, 19mmHg, and 19mmHg, respectively) with an almost equal cardiac index. Based on the examination we implanted a permanent pacemaker for Direct His-bundle pacing (DHBP). After the DHBP implantation, the LVEF immediately improved from 40% to 55%, and BNP level decreased from 422 pg/ml to 42 pg/ml. The number of premature ventricular complex (PVC) was decreased, and non sustained ventricular tachycardia (NSVT) disappeared. Pacing threshold for His-bundle pacing has remained at the same level. His-bundle pacing has been maintained during 27 months and her long-term DHBP can improve cardiac function and the NYHA functional class

Effects of Statin versus the Combination of Ezetimibe plus Statin on Serum Lipid Absorption Markers in Patients with Acute Coronary Syndrome

Background. The use of statins is essential for aggressive lipid-lowering treatment in acute coronary syndrome (ACS) patients with dyslipidemia. Recently, elevation of sitosterol, a lipid absorption marker, was reported to be associated with premature atherosclerosis. The purpose of the present study was to examine the impact of ezetimibe, a selective intestinal cholesterol transporter inhibitor, in ACS patients. Methods. A total of 197 ACS patients were randomized to pitavastatin + ezetimibe (n=100) or pitavastatin (n=97). Low-density lipoprotein cholesterol (LDL-C) and sitosterol levels were evaluated on admission and after 12 weeks. Results. After 12 weeks, the pitavastatin + ezetimibe group showed a significantly greater decrease of sitosterol (baseline versus after 12 weeks; 2.9 ± 2.5 versus 1.7 ± 1.0 ng/mL, P<0.001) than the pitavastatin group (2.7 ± 1.5 versus 3.0 ± 1.4 ng/mL). The baseline sitosterol level was significantly higher in patients with achieved LDL-C levels ≥ 70 mg/dL than in patients with levels < 70 mg/dL (3.2 ± 2.5 versus 2.4 ± 1.3 ng/mL, P=0.006). Conclusions. Ezetimibe plus statin therapy in ACS patients with dyslipidemia decreased LDL-C and sitosterol levels more than statin therapy solo. Sitosterol Elevation was a predictor of poor response to aggressive lipid-lowering treatment in ACS patients

Rate Pressure Products Affect the Relationship between the Fractional Flow Reserve and Instantaneous Wave-Free Ratio

The rate pressure product (RPP) is an index of myocardial metabolism that correlates closely with myocardial hemodynamics. The relationship between the RPP and the fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) is not known. In this study, we investigated the effects of the RPP on the FFR and iFR. We retrospectively enrolled 195 patients (259 lesions) who had undergone invasive coronary angiography and both the iFR and FFR examinations between 2012 and 2017. The RPP was defined as systolic blood pressure multiplied by the heart rate, measured prior to the iFR evaluation. The study population was divided into the low-RPP (n = 129, mean RPP: 6981 ± 1149) and high-RPP (n = 130, mean RPP: 10391 ± 1603) groups according to the median RPP. Correlations and biases between the iFR and FFR were compared. The diagnostic performance of the iFR in the groups was calculated, using FFR as the gold standard. The correlation between the iFR and FFR was higher in the high-RPP group than in the low-RPP group. The bias between the iFR and FFR in the high-RPP group was smaller than that in the low-RPP group. The best cutoff value of the iFR for predicting an FFR of 0.8 was 0.90 for all lesions, 0.93 for the low-RPP group, and 0.82 for the high-RPP group. The iFR and RPP showed a weak but a statistically significant negative correlation (R = 0.14; p=0.029). This was not observed for the relationship between the FFR and RPP. In conclusion, the RPP affects the relationship between the FFR and iFR. With FFR as the gold standard, the iFR may underestimate and overestimate the functionality of ischemia in the low- and high-RPP groups, respectively

Bacterial communities adapted to higher external resistance can reduce the onset potential of anode in microbial fuel cells

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Impact of Serial Coronary Stenoses on Various Coronary Physiologic Indices

Background: Determining the functional significance of each individual coronary lesion in patients with serial coronary stenoses is challenging. It has been proposed that nonhyperemic pressure ratios, such as the instantaneous wave free ratio (iFR) and the ratio of resting distal to proximal coronary pressure (Pd/Pa) are more accurate than fractional flow reserve (FFR) because autoregulation should maintain stable resting coronary flow and avoid hemodynamic interdependence (cross-talk) that occurs during hyperemia. This study aimed to measure the degree of hemodynamic interdependence of iFR, resting Pd/Pa, and FFR in a porcine model of serial coronary stenosis. Methods: In 6 anesthetized female swine, 381 serial coronary stenoses were created in the left anterior descending artery using 2 balloon catheters. The degree of hemodynamic interdependence was calculated by measuring the absolute changes in iFR, resting Pd/Pa, and FFR across the fixed stenosis as the severity of the other stenosis varied. Results: The hemodynamic interdependence of iFR, resting Pd/Pa, and FFR was 0.039±0.048, 0.021±0.026, and 0.034±0.034, respectively (all P<0.001). When the functional significance of serial stenoses was less severe (0.70-0.90 for each index), the hemodynamic interdependence was 0.009±0.020, 0.007±0.013, and 0.017±0.022 for iFR, resting Pd/Pa, and FFR, respectively (all P<0.001). However, in more severe serial coronary stenoses (<0.60 for each index), hemodynamic interdependence was 0.060±0.050, 0.037±0.030, and 0.051±0.037 for iFR, resting Pd/Pa, and FFR, respectively (all P<0.001). Conclusions: When assessing serial coronary stenoses, nonhyperemic pressure ratios are affected by hemodynamic interdependence. When the functional significance of serial coronary stenoses is severe, the effect is similar to that which is seen with FFR