“Background: To evaluate the acute hemodynamic effects of different right (RV) and left ventricular (LV) pacing sites in patients undergoing the implantation of a cardiac resynchronization therapy defibrillator (CRT-D).
Methods: Stroke volume index (SVI), assessed via pulse contour analysis, and dp/ dt max, obtained in the abdominal aorta, PND-1186 cost were analyzed in 21 patients with New York Heart Association class III heart failure and left bundle branch block (mean ejection fraction of 24 +/- 6%), scheduled for CRT-D implantation under general anesthesia. We compared the hemodynamic effects of RV apical (A), RV septal (B),
and biventricular pacing using the worst (lowest SVI; C) and best (highest SVI; D) coronary sinus lead positions.
Results: Mean arterial pressure, SVI, and dp/dt max did not differ significantly between RV apical and septal pacing. Dp/dt max and SVI increased significantly during biventricular
pacing (dp/dt max: B, 588 +/- 160 mmHg/s; C, 651 +/- 218 mmHg/s, P = 0.03 vs B; D, 690 +/- 220 mmHg/s, P = 0.02 vs C; SVI: B, 33.6 +/- 5.5 mL/m(2), C, 34.8 +/- 6.1 mL/m(2), P = 0.08 vs B, D 36.0 Small molecule library manufacturer +/- 6.0 mL/m(2), P < 0.001 vs C). The best hemodynamic response was associated with lateral or inferior lead positions in 15 patients. Other LV lead positions were most effective in six patients.
Conclusions: The optimal LV lead position varies significantly among patients and should be individually determined during CRT-D implantation. The impact of the RV stimulation site in patients with intraventricular conduction delay, undergoing
CRT-D implantation, has to be investigated in further studies. (PACE 2011; 34: 1537-1543)”
“We have theoretically studied the full counting statistics of electron transport through a single-molecule magnet (SMM) with an arbitrary angle between the applied magnetic field and the SMM’s easy axis above the sequential tunneling threshold, since the angle theta cannot be controlled in present-day SMM experiments. In the absence of the small transverse anisotropy, when the coupling of the SMM with the incident-electrode is stronger than that with the outgoing-electrode, i.e., Gamma(L)/Gamma(R) >> 1, the maximum peak of shot noise first increases and then decreases with increasing BTSA1 manufacturer h from theta to 0.5 pi. In particular, the shot noise can reach up to a super-Poissonian value from a sub-Poissonian value when considering the small transverse anisotropy. For Gamma(L)/Gamma(R) << 1, the maximum peaks of the shot noise and skewness can be reduced from a super-Poissonian to a sub-Poissonian value with increasing theta from 0 to 0.5 pi; the super-Poissonian behavior of the skewness is more sensitive to the small theta than shot noise, which is suppressed when taking into account the small transverse anisotropy. These characteristics of shot noise can be qualitatively attributed to the competition between the fast and slow transport channels.