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Notes: This study evaluates the short-term changes in coronary artery segments treated with high speed rotational atherectomy (HSRA). Quantitative coronary angiographic (QCA) analysis indices, such as degree of expected ablation, elastic recoil, and segmental spasm, were examined in 133 patients and restudied 24 hours after HSRA. The study was also designed to compare the early results of three different HSRA strategies: stand-alone (SA) HSRA; HSRA with adjunctive high (≥ 4 atm) pressure (HP BA) and low (≥ 2 atm) pressure balloon angioplasty (LP BA). Previous studies have suggested negligible elastic recoil after HSRA as well as demonstrated the possibility of further continuous improvement in vessel patency up to 24 hours postprocedure. From a total of 656 patients treated with HSRA, a cohort of 133 patients with successful HSRA of 167 lesions were restudied angiographically at 24 hours. Serial QCA evaluation of the treatment site was performed. Analysis of the relative gain in minimal luminal diameter (MLD) assessed at 24 hours postprocedure showed that the highest gain group (〉 40%) had narrower initial lesions compared to moderate gain (1%–40%), or MLD loss groups (MLD 0.5 ± 0.4 mm vs 1.0 ± 0.3 and 1.5 ± 0.4, respectively, P 〈 0.01). The initial percent diameter stenosis was also higher in the high gain group (77.1 ± 16.0 vs 61.9 ± 11.8 and 53.0 ± 11.9, P 〈 0.01). Immediately postprocedure there was a significant increase in MLD and a decrease in percent diameter stenosis. There was no difference in residual lesion characteristics postprocedure. While progressive MLD decrease was observed in the loss group (MLD postprocedure 1.6 ± 0.5 and 1.2 ± 0.6 at 24 hours, P 〈 0.01), a continuous increase in MLD was noted in the high gain group (MLD postprocedure 1.7 ± 0.5 mm vs at 24 hours 2.0 ± 0.5 mm, P 〈 0.01). The high gain group was characterized by the most lesion debulking, the most pronounced segmental spasm, and the least elastic recoil. Adjunctive HP BA was associated with the largest size vessels (D ref. in SA HSRA group was 2.6 ± 0.8 mm vs 2.9 ± 0.6 mm in LP BA and 3.0 ± 0.7 mm in HP BA groups, P 〈 0.01), the lowest elastic recoil (SA HSRA 23.8%± 20.9% vs LP BA 15%± 16.8% and HP BA 5.7%± 14.4%, P 〈 0.05), and the highest incidence of vessel dissection (SA HSRA 8.1% vs LP BA 14.7% and HP BA 34.0%, P 〈 0.05). However, these larger vessels underwent the least amount of lesion debulking (SA HSRA 46.4%± 27.2% vs LP BA 38.6%± 24.0% and HP BA 30.5%± 19.5%, P SA HSRA vs. HP BA 〈 0.001). There are measurable degrees of elastic recoil and local spasm observed after HSRA. HSRA of the most severe lesions yields the highest procedural gain, the lowest elastic recoil and the highest index of lesion ablation. In addition, some late increase in the MLD due to the resolution of spasm is observed at 24 hours postprocedure. SA HSRA is associated with higher degrees of expected lesion ablation. This is comparable to the degree of improvement in MLD, where adjunctive percutaneous transluminal coronary angioplasty is utilized as assessed at 24 hours postprocedure. HSRA with adjunctive HP BA yields immediate results showing the least elastic recoil and spasm at the expense of the highest incidence of dissection and side branch loss.

Notes: Objectives: The present study assesses clinical outcomes in patients from the Potential Angina Class Improvement From Intramyocardial Channels (PACIFIC) trial of percutaneous transmyocardial revascularization (PTMR) who had previously been considered “no-option,” but who subsequently underwent percutaneous coronary intervention (PCI) for continuing symptoms. Background: Patients with advanced symptomatic coronary artery disease who are not candidates for coronary artery bypass grafting (CABG) or PCI comprise an important group, for which no established treatment is currently available. These patients have been described as having “no option,” and are currently targeted for various experimental therapies. One such proposed therapy, PTMR, was recently examined in the PACIFIC trial. A subgroup of patients in this trial subsequently underwent PCI, although to initially qualify for the study they had previously been considered as unsuitable for PCI and as having “no option.” The therapeutic benefit of PCI for patients of this type is unknown. Methods: A retrospective analysis was performed on data obtained from all subjects of the PACIFIC study who underwent PCI within the 12-month follow-up period. Results: Ten subjects originally randomized to PTMR and 11 subjects from the medical treatment group underwent PCI. Most had undergone at least one prior PCI and at least one CABG, and there was a high prevalence of cardiovascular risk factors. Despite excellent immediate procedural success, PCI resulted in only modest, statistically nonsignificant increases in mean exercise duration, small improvements in angina status, and no significant improvements in quality of life. Conclusions: These data suggest that PCI provides only marginal—if any—symptomatic benefit in these patients. (J Interven Cardiol 2004;17:87–91)

Notes: Transmyocardial laser revascularization (TMR) is an experimental procedure for intractable angina that has demonstrated clinical benefit. The majority of patients who had TMR have significant reduction of angina. TMR has been performed exclusively by thoracic and cardiac surgeons using a handhold CO2 laser device. The development of a prototype percutaneous device that delivers mid-infrared laser energy (Ho:YAG) through a 9Fr coaxial catheter system recently has been reported. The long-term benefits of this percutaneous approach is being defined in the context of the randomized PACIFIC Trial. The initial follow-up suggested significant relief of angina in the majority of treated patients, and the results are likely to be equal or similar to those of surgical TMR. The safety data of percutaneous myocardial revascularization (PMR) with the CardioGenesis system showed exceedingly low morbidity and mortality.

Notes: Traditional approaches to improve myocardial perfusion in patients with coronary artery disease previously have applied methods to restore blood flow through the existing coronary vessels. In contrast laser myocardial revascularization techniques rely on the creation of new myocardial channels to produce effects leading to improved perfusion and reduction in angina. Laser transmyocardial revascularization (TMR) is performed via open thoracotomy to access the epicardial surface, is relatively safe, and appears to have a beneficial effect on myocardial perfusion. Percutaneous myocardial revascularization (PMR), however, uses transmission of laser energy along a flexible, fiber-optic catheter, thus permitting creation of laser channels from the endocardial surface of the left ventricle via a femoral artery approach. Tissue responses to lasers are dependent upon the energy used and its means of delivery, thermal, mechanical, or chemical effects of laser channel creation may all impact on the myocardium, although stimulation of angiogenic growth factors, with consequent neovascularization appears to be the principal underlying mechanism responsible for improvement in myocardial perfusion. Patients with severe, chronic angina refractory to drug therapies and in whom standard surgical or angioplasty revascularization approaches are not possible may be candidate for TMR or PMR techniques. Clinical studies of TMR have described reductions in angina class, hospital admissions, and the number of myocardial perfusion defects. PMR studies have reported improvements in angina class, increased exercise duration, and trends toward improvement in radionuclide perfusion defects. Randomized trials are underway and will provide more definitive insights into the future clinical role of laser myocardial revascularization techniques.

Notes: Results on molecular beam epitaxy-grown microcavity light-emitting diodes with InGaAs/GaAs quantum wells and a hybrid top mirror are presented. An external quantum efficiency of 14.8% is achieved for a 400 μm diam light-emitting diode. The strong influence of the spectral overlap between the spontaneous emission spectrum and the cavity resonance mode on the radiation pattern is shown. The angular emission profile is compared with model predictions for different detunings, and a very good agreement is obtained when the asymmetric spectral broadening of the intrinsic spontaneous emission is taken into account. © 1998 American Institute of Physics.

Notes: A new modification is described for the fractionation of nucleic acids from brain. The cold phenol method followed by a hot extraction was combined with ‘salt-precipitation’ and chromatography on Sephadex and Agarose gels. The method enables the isolation of five highly purified fractions in large amounts: DNA; high molecular weight salt-soluble RNA, a hitherto undescribed fraction; rRNA; residual RNA (mRNA) and sRNA. All fractions showed, after 9 h in vivo incubation with 32P, different specific radioactivities and/or characteristic base compositions. The single mononucleotides of each RNA fraction differed markedly in their 32P-labelling rate. This was found to be a new characteristic, for these differences were in no way similar in the various RNAs, but specific and constant for each fraction. An assay of base composition only by 32P-labelling was therefore not possible.

Notes: We have grown a very high finesse microcavity using distributed Bragg reflectors of AlxGa1−xAs and AlAs. The measured Fabry–Pérot mode has a linewidth of 0.84 A(ring) at 930 nm. This implies a finesse in excess of 5500 and an effective (mirror corrected) finesse greater than 1450. Comparison with theoretical calculations for such a structure shows that (i) the growth rates are stable to 0.25% over 14 h and (ii) the internal losses are less than 1 cm−1. © 1994 American Institue of Physics.

Notes: The coupled semiconductor microcavity is a system in which there are three oscillators, two photonic and one electronic (quantum well excitons). It develops three strongly coupled modes which allow a wide design range for a variety of optoelectronic applications. The MBE grown structure is comprised of two λ sized GaAs cavities containing InxGa1−xAs quantum wells, separated by a common mirror. Reflectivity measurements show both two coupled photon mode behavior and three coupled mode behavior, i.e., two photon and one exciton, depending on the relative position of the exciton resonance. © 1994 American Institute of Physics.

Notes: We report photopumped operation of a monolithic coupled semiconductor microcavity laser. The structure consists of two λ-sized GaAs vertical cavities, one on top of the other, coupled together through a common mirror. Due to a wedge induced into each cavity, the detuning between the cavities can be continuously varied when moving across the sample. Depending on the detuning, laser action is simultaneously achieved at two different wavelengths or occurs only at one wavelength. At resonance, we observe coupled dual-wavelength laser emission at two widely spaced wavelengths (13 nm) with the same threshold and same dependence on pump power. © 1997 American Institute of Physics.