ABSTRACT
<p><b>BACKGROUND</b>Cardiac resynchronization therapy (CRT) with biventricular pacing improves cardiac function, functional capacity and quality of life in selected patients with heart failure. The current study aimed to evaluate the efficacy of the intracardiac electrogram (IEGM)-based optimization method, QuickOpt(TM), in Chinese patients treated with CRT.</p><p><b>METHODS</b>Aortic time velocity integrals (AVTI) achieved at the sensed atrioventricular (AV), paced AV and interventricular (VV) interval settings recommended by both QuickOpt(TM) and standard echocardiographic optimization were measured in 101 patients. Consistency and the strength of the relationship between the two timing cycle optimization methods were assessed by intra-class correlation coefficient (ICC).</p><p><b>RESULTS</b>The ICC showed good agreement and correlation with what the AVTI achieved at the optimal sensed AV (ICC = 0.9683 (0.9535 - 0.9785)), paced AV (ICC = 0.9642 (0.9475 - 0.9757)) and VV (ICC = 0.9730 (0.9602 - 0.9817)) interval settings determined by the two optimization methods. The average time required by echocardiographic optimization and by QuickOpt(TM) were (78.32 ± 32.40) minutes and (1.98 ± 1.64) minutes respectively (P < 0.0001).</p><p><b>CONCLUSION</b>The QuickOpt(TM) algorithm provides a quicker, simpler and reliable alternative to the standard method for timing cycle optimization.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Cardiac Resynchronization Therapy , Methods , Electrophysiologic Techniques, Cardiac , Methods , Heart Failure , Therapeutics , Prospective StudiesABSTRACT
<p><b>OBJECTIVE</b>To study the effect of parthenolide on the proliferation of vascular smooth muscle cell(VSMC) and its mechanism.</p><p><b>METHOD</b>Vascular smooth muscle cell was cultured, the protein levels of c-fos, c-myc, p15, p16, p18, p19 were measured by Western blot method, cell cycle were examined with flow cytometry, and the DNA synthesis was determined by [3H]-TdR incorporation.</p><p><b>RESULT</b>Parthenolide inhibited protein levels of c-fos, c-myc in a time-dependent manner but didn't affect the protein levels of p15, p16, p18, p19. Flow cytometric DNA analysis revealed that parthenolide increased significantly G0/G1 phase of VSMC and decreased S phase of VSMC in a dose-dependent manner. Parthenolide inhibited [3H]-TdR incorporation in a dose dependent manner.</p><p><b>CONCLUSION</b>Parthenolide may inhibit proliferation of VSMC by inhibiting the expressions of c-fos, c-myc, but not the expressions of p15, p16, p18, p19.</p>