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FiberNet ® is a second generation non-conventional embolization protection device (EPD) that purports to offer several advantages: ability to capture debris as small as 40 sum, more flexibility with placement and positioning in curved segments requiring a small landing zone, ability to conform to asymmetric vessels, and improved deliverability. The design features a low profile with large surface area to capture debris. Legitimate concerns include inducement of obstruction or low flow with debris capture and requirements in the IFU to aspirate during re-capture and device removal. Our goal was to compare the results of carotid artery stenting (GAS) using FiberNet® against a multi-center experience of GAS using other filter devices to identify any differences in technical success or event rates. FiberNet® (n=25) results were compared to all GAS cases performed at the Mayo Clinic in Rochester, MN, St Mary's/Duluth Clinic in MN, and North Central Heart Institute in Sioux Falls, SD (n250) from March 2001 to December 2008. Chi -square or means were used to compare variables, as appropriate. Bivariate logistic regression was used to identify possible correlates of adverse outcome. Statistical significance was set at < 0.05. FiberNet® patients were more likely to be older (78.1+5.4 vs 73.6+9.4, p=0.019), female (48% vs 29%, p=0.047'), and havepe- ripheral vascular disease (84.0% vs 37.2%, p=0.025), and less likely to have diabetes (8.0% vs 29.8%, p=0.012) than patients in the comparison group. FiberNet® patients had more lesion calcification (40.0% vs 18.9%, p=0.014) and increased number of type 2 and 3 arches (44.2% vs 73.9%, p=0.006). Procedural success rate was 100% in both groups. None of the FiberNet® patients showed evidence of stagnant flow. The thirty-day outcome for TL4, CVA, or death was 4% in FiberNet® versus 4.8% in the comparison group (p NS). None of the independent variables - age gender, serum creatinine, arch complexity, lesion length, lesion calcium, lesion thrombus, PVD, diabetes, contralateral carotid occlusion, or ipsilateral carotid endarterectomy - predicted adverse events. Although FiberNet ®patients had more lesion calcium and more challenging arch anatomy, procedural success and ad- verse events were comparable between groups. The advantages of FiberNet ® can be applied to GAS with good technical results and may be a promising EPD for certain high-risk situations. [ABSTRACT FROM AUTHOR]

Transcatheter valve-in-valve (VIV) implantation has been recently proposed as an alternative to surgical reoperative aortic valve replacement in patients with a failing aortic bioprosthesis. Experience with transcatheter VIV implantation at other valve positions is very limited. Herein is reported the case of an 18-year-old man with Ebstein's anomaly and severe tricuspid valve (TV) regurgitation status after bioprosthetic valve replacement, who developed new dyspnea on exertion three years after the initial valve replacement. Transesophageal echocardiography showed a severely dilated right atrium and new TV stenosis with an immobile leaflet. The patient underwent successful VIV implantation of a 29-mm SAPIEN XT bioprosthetic valve, with resolution of symptoms and no residual TV regurgitation or stenosis at the two-year follow up. Video 1: Degenerative bioprosthetic tricuspid valve. TEE showing the degenerative bioprosthetic tricuspid valve, and color Doppler during systole showing severe tricuspid regurgitation. Video 2: Degenerative bioprosthetic tricuspid valve. Three-dimensional TEE showing stenosis with an immobile leaflet creating a coaptation defect, viewed from the right atrium. Video 3: Transcatheter VIV replacement with a 29-mm Edwards SAPIEN XT deployed within the tricuspid valve prosthesis. Final result after valve implantation, demonstrating a patent valve orifice, and appropriate apposition of transcatheter valve within a pre-existing surgical Carpentier-Edwards bioprosthetic valve, viewed from the right ventricle. Video 4: Transcatheter VIV replacement with a 29-mm Edwards SAPIEN XT deployed within the tricuspid valve prosthesis. Final result after valve implantation, demonstrating a patent valve orifice, and appropriate apposition of transcatheter valve within a pre-existing surgical Carpentier-Edwards bioprosthetic valve, viewed from the right atrium.

A goal of clinicians caring for heart transplant recipients has been to use heart rate variability as a noninvasive means of diagnosing graft rejection. The determinants of beat-to-beat variability in the surgically denervated heart have yet to be elucidated. We used an isolated, blood buffer-perfused porcine heart preparation to quantitatively assess the relationship between coronary perfusion and sinus node automaticity. Hearts (n = 9) were suspended in a Langendorff preparation, and heart rate (HR) fluctuations were quantified while perfusion pressure was modulated between 70/50, 80/60, 90/70, and 100/80 mmHg at 0.067 Hz. In 32 of 32 recordings, the cross spectrum of perfusion pressure vs. HR showed the largest peak centered at 0.067 Hz. In eight of nine experiments during nonpulsatile perfusion, HR accelerated as perfusion pressure was increased from 40 to 110 mmHg (mean increase 24.2 +/- 3.0 beats/min). HR increased 0.34 beats/min per mmHg increase in perfusion pressure (least squares linear regression y = -25.8 mmHg + 0.34x; r = 0.88, P < 0.0001). Administration of low- and high-dose nitroglycerin (Ntg) resulted in a modest increase in flow but produced a significant decrease in HR and blunted the response of HR to changes in perfusion pressure (HR increase 0.26 beats. min-1. mmHg-1, r = 0.87, P < 0.0001 after low-dose Ntg; 0.25 beats. min-1. mmHg-1, r = 0.78, P < 0.0001 after high-dose Ntg). These experiments suggest that sinus node discharge in the isolated perfused heart is mechanically coupled to perfusion pressure on a beat-to-beat basis.

1. The present study was performed to test whether beat-to-beat cardiovascular control in cardiac allograft recipients resides in cholinergic and/or adrenergic nerves that are intrinsic to the heart. 2. Heart rate (HR) fluctuations synchronous with respiration during spontaneous, double tidal volume and metronome-synchronized breathing were quantified in 13 human heart transplant recipients. We also examined the effects of sequential cholinergic and beta-adrenoceptor (combined) autonomic blockade on respiratory sinus arrhythmia (RSA). We computed RSA amplitude and the correlation between respiration and changes in HR (cardiopulmonary synchronization; CPS). Group means were compared using repeated-measures analysis of variance. Transplant recipients served as their own controls. 3. In the basal state, moderate RSA amplitude and CPS were observed. During cholinergic and combined blockade, we observed no significant change in RSA amplitude, whereas CPS increased significantly during combined blockade (P < 0.05). The amplitude of RSA increased during respiration at double baseline tidal volume, but not at any of the other breathing manoeuvres (P < 0.01). In contrast, CPS increased significantly during both patterned breathing manoeuvres. No significant correlation was seen between mean right atrial pressure and RSA amplitude. In 23% of subjects with low CPS, HR oscillated with arterial pressure. These oscillations were independent of respiration. During all three patterns of respiration, a significant inverse correlation was observed between CPS and pulse pressure (r = -0.53 to -0.73). Thus, as the amplitude of pulse pressure increased, respiration accounted for a smaller percentage of HR variation. 4. In conclusion, RSA persists and the magnitude of CPS increases following combined autonomic blockade. These studies suggest that while RSA after cardiac transplantation is not cholinergically or adrenergically mediated, it may be related to mechanical stretch of the sinus node caused by changes in intrathoracic pressure and perfusion pressure.

Babesiosis is a malaria-like illness transmitted by the tick Ixodes dammini. The disease is endemic to the Northeast coastal region and parts of the Midwest. Symptoms-which include fever, anemia, elevated liver function tests, and hemoglobinuria-may be especially severe in asplenic or immunocompromised patients. In rare cases, infection with Babesia may be associated with marked pancytopenia. Bone marrow biopsy may reveal hemophagocytosis and marrow histiocytosis. We report a severe case of babesiosis and hemophagocytic syndrome in an asplenic renal transplant patient.

The surface electrocardiogram (ECG) has been used as a noninvasive technique for the diagnosis of cardiac allograft rejection. Alteration in conduction, R-wave amplitude, and rhythm have been associated with rejection. These ECG findings are modulated by the myocyte sodium channel, but are inconsistent and occur only during severe rejection episodes. The purpose of this study was to (1) characterize changes in cardiac electrophysiology during allograft rejection using the highly sensitive intramyocardial electrocardiogram and (2) determine whether pharmacological sodium channel blockade with procainamide enhances subtle ECG changes. Nine mongrel dogs underwent heterotopic heart transplantation in which four intramyocardial leads (one anteriorly and posteriorly on each ventricle) were attached. Leads exited to a subcutaneously placed ECG block which was transcutaneously accessed posttransplant to record direct intramyocardial electrocardiograms. Six animals were treated with procainamide, while three were not and served as controls. Daily measurements included the QRS, QT, and QTc intervals and the R-wave amplitude. Endomyocardial biopsies were performed weekly and also when significant decline in ECG amplitude occurred. Detailed ECG interval analysis failed to establish any correlation between conduction and rejection, even in the procainamide-treated group. Intramyocardial amplitude analysis, however, had a sensitivity of 100% and a specificity of 86% for the diagnosis of rejection. The results indicate that intramyocardial ECG interval analysis is not predictive of rejection even when prolonging conduction with procainamide. Amplitude analysis, however, remains an accurate noninvasive means for the early detection of cardiac allograft rejection and should allow more selective use of endomyocardial biopsy.

Since the advent of cyclosporin A surface electrocardiograms have been unreliable for diagnosing cardiac allograft rejection. Although several noninvasive methods have been proposed, none have been sufficiently accurate to be considered for clinical use. We have studied the use of the QRS complex amplitude, the unipolar peak-to-peak amplitude, recorded from intramyocardial electrodes for detecting rejection. Ten adult mongrel dogs underwent placement of intramyocardial electrodes on each ventricle. After stabilization of signals the hearts were transplanted heterotopically into unmatched recipients receiving cyclosporin A, azathioprine and methylprednisolone. Endomyocardial biopsies were performed after stabilization of unipolar peak-to-peak amplitude, twice weekly thereafter, and when unipolar peak-to-peak amplitude fell significantly. This detected 13 of 14 episodes of rejection. There was one false-positive and one false-negative result. The false-negative study became positive the following day. Thus, analysis of unipolar peak-to-peak amplitude detected all episodes of rejection in a clinically relevant time frame and was able to detect mild forms of rejection and multiple episodes of rejection in the same heart even in the presence of therapeutic levels of cyclosporin A.

The use of local dihematoporphyrin ether (DHE) injections, followed by laser light activation, was investigated as a potential permanent myectomy treatment for muscle spasms, in particular blepharospasm and hemifacial spasm. DHE was injected into the eyelids of rabbits, followed by laser activation, as used in photochemotherapy. Four days after treatment, histological examination indicated that doses of greater than or equal to 0.5 mg of DHE and laser treatment with an energy density of at least 100 J/cm2 resulted in an almost total destruction of the orbicularis oculi muscle in the treated eyelid. The amount of muscle injury was dependent on both dose of DHE and energy density levels. Histologically, the tarsal glands and conjunctiva were damaged. Glandular tissue was markedly reduced, and the conjunctival epithelium showed hyperplasia and a loss of mucous cells. Six months after DHE and laser treatment, the majority of the muscle tissue had regenerated, although there was evidence of previous injury. While DHE injections combined with laser light activation were lethal to muscle at the site of treatment, this treatment was not permanent. The orbicularis oculi muscle retained its ability to regenerate. However, photochemomyectomy may be studied further as an adjuvant treatment to temporarily injure and debulk large muscles when botulinum toxin is contraindicated due to the large doses involved or as a permanent treatment when used together with an antimitotic agent such as doxorubicin.