A new set of eyes: development of a novel microangioscope for neurointerventional surgery.

BACKGROUND: Endovascular technological advances have revolutionized the field of neurovascular surgery and have become the mainstay of treatment for many cerebrovascular pathologies. Digital subtraction angiography (DSA) is the 'gold standard' for visualization of the vasculature and deployment of endovascular devices. Nonetheless, with recent technological advances in optics, angioscopy has emerged as a potentially important adjunct to DSA. Angioscopy can offer direct visualization of the intracranial vasculature, and direct observation and inspection of device deployment. However, previous iterations of this technology have not been sufficiently miniaturized or practical for modern neurointerventional practice. OBJECTIVE: To describe the evolution, development, and design of a microangioscope that offers both high-quality direct visualization and the miniaturization necessary to navigate in the small intracranial vessels and provide examples of its potential applications in the diagnosis and treatment of cerebrovascular pathologies using an in vivo porcine model. METHODS: In this proof-of-concept study we introduce a novel microangioscope, designed from coherent fiber bundle technology. The microangioscope is smaller than any previously described angioscope, at 1.7 F, while maintaining high-resolution images. A porcine model is used to demonstrate the resolution of the images in vivo. RESULTS: Video recordings of the microangioscope show the versatility of the camera mounted on different microcatheters and its ability to navigate external carotid artery branches. The microangioscope is also shown to be able to resolve the subtle differences between red and white thrombi in a porcine model. CONCLUSION: A new microangioscope, based on miniaturized fiber optic technology, offers a potentially revolutionary way to visualize the intracranial vascular space.

Pulmonary vein isolation with a novel endoscopic ablation system using laser energy.

Pulmonary vein isolation (PVI) is the basis of all ablation techniques for paroxysmal atrial fibrillation. Performing conventional radiofrequency ablation for PVI is time consuming and sometimes challenging when using point-by-point applications to create continuous lesions. Small electrically conducting gaps evolving in the ablation lines may cause recurrences of atrial fibrillation or regular atrial re-entry tachycardias. Development of novel anatomically designed ablation catheters for PVI aim to facilitate the ablation procedure, to produce continuous and durable lesions with a limited number of ablation impulses and to reduce the complication rate. The endoscopic laser balloon ablation system (HeartLight® EAS, Cardiofocus Inc.) is the first system that allows direct visual guidance of energy delivery at the antral level of each pulmonary vein and uses a completely new energy source for ablation.

Reduction in ruptured aortic aneurysms is not due to increases in endovascular repairs.

We sought to determine if the shift from open abdominal aortic repair to endovascular methods has affected the incidence of rupture of abdominal aortic aneurysms (rAAA). The Nationwide Inpatient Samples 2001 to 2007 was used. The incidence of rAAA and myocardial infarction (MI) as well as the number and type of aneurysm repairs were tabulated. There were no significant changes in the number of diagnosed (56,991 to 51,122; P = 0.26) and repaired (45,828 to 43,900; P = 0.79) abdominal aortic aneurysms between 2001 and 2007. Open abdominal aortic repair decreased from 31,989 to 13,876 (P < 0.001) whereas the number of endovascular aneurysm repairs increased from 13,839 to 30,025 (P < 0.001). In the same time, rAAA decreased from 7,749 to 5,267 (-32%, P < 0.001). The reduction of rAAA was greatest (-35.5%) in patients 65 to 84 years of age and less in patients 85 years and older (-15%). The number of MI decreased from 773,871 to 624,936 (P = 0.005). The decrease in rAAA was significantly correlated with decreases in MI (r = 0.97, P = 0.0003). Although endovascular aneurysm repair increased, the overall application of abdominal aortic aneurysms repair did not change and does not account for the reduction in rAAA. It is more likely that environmental or other risk factor modifications also predisposing to decreases in MI account for the reduction in rAAA.

[Angioscopy: a new intraoperative diagnostic and interventional tool for thoracic aortic treatment]. / Angioskopie: Neues intraoperatives diagnostisches und interventionelles Verfahren für die Therapie der thorakalen Aortenerkrankung.

In complex thoracic aortic disease endovascular techniques and the use of hybrid stent grafts enables a combination therapy of the aortic arch and the descending aorta through a median sternotomy. This emphasizes the importance of intraoperative visualization of the descending aorta and its pathologies. Intraoperative angioscopy is a new diagnostic method for the assessment of distal aortic disease and assists in therapeutic decision-making and navigation of endovascular techniques in the descending aorta. This study presents the angioscopic results of 62 patients (mean age 60±12 years, 73% male, 54 aortic dissections, eight aortic aneurysms) during surgery of the thoracic aorta. Visualization of the extent of pathology along the downstream aorta was feasible in all patients. The implantation of a hybrid stent graft prosthesis was assisted by angioscopy in 34 patients and endovascular balloon dilatation of the stent graft was navigated by angioscopy in 11 patients. Angioscopy has become an indispensable tool in the intraoperative treatment of complex thoracic aortic disease in our clinic, particularly in the navigation of endovascular interventions in the distal thoracic aorta through the aortic arch.

Future perspectives in the treatment of femoro-popliteal arterial occlusions.

Femoro-popliteal occlusive disease represents the most frequent localization of atherosclerosis in the lower extremities. Treatment of this disease has changed remarkably in the last decade. A definite treatment strategy has still to be established. The pathophysiology is described. A general overview of the state-of-the art treatment modalities and the most recent developments is given. This is divided into non-interventional preventive and supportive therapy, endovascular interventional therapy, and surgical interventional therapy. The development of medical therapy has expanded enormously and is progressing still. In the wide range of interventional treatment modalities, there has been a change from invasive bypass surgery to more refined techniques like endarterectomy and percutaneous endovascular therapy. This trend towards restoring the patency of the artery using the vessel wall itself as a conduit, leads to a term encompassing all these treatment modalities, known as restorative intervention. Peri-procedural risks of restorative interventions are of a much lesser degree compared to bypass surgery. Reports of patency rates show a steady increase. It is expected that patency rates will eventually equal or even surpass those of bypass surgery. In conclusion, a treatment strategy for femoro-popliteal occlusions in the future is proposed as follows: the first line of interventional therapy in femoro-popliteal occlusions should be a restorative intervention. With adequate adjuvant medical therapy and sufficient monitoring, this will be the definite treatment for the majority of patients. Bypass surgery should be regarded as the second line of interventional therapy and should be reserved for those patients in whom restorative interventions fail.

Endografting increases total volume of AAA repairs but not at the expense of open surgery: experience in more than 1000 patients.

PURPOSE: To compare the volume of open graft replacements (OGR) for abdominal aortic aneurysm (AAA) versus endovascular aneurysm repairs (EVAR) over time and after modifying selection criteria. METHODS: A review was conducted of 1021 consecutive patients who underwent AAA repair from 1989 through 2002: 496 elective OGRs for infrarenal AAAs (STANDARD), 289 elective EVARs for infrarenal AAAs, 59 complex OGRs for suprarenal AAAs, and 177 emergent OGRs for ruptured AAAs. Patients from 1995 to 2002 were divided into 2 groups based on shifting treatment strategies; 454 patients were treated by STANDARD or EVAR at the surgeon's discretion between 1995 and 2000 (post EVAR). The second group comprised 161 patients treated in 2001-2002 after the introduction of "high-risk" screening criteria (age > or = 72 years, diabetes mellitus, renal dysfunction, impaired pulmonary function, or ASA class IV) that dictated EVAR whenever anatomically feasible. For comparison, 170 STANDARD repairs performed in the 6 years prior to EVAR served as a control. RESULTS: While surgery for ruptured AAAs remained fairly stable over the 14-year period, the number of patients undergoing elective repair increased due to the implementation of EVAR. During the 6 years after its introduction, EVAR averaged 34.3 patients per year; after 2001, the annual frequency of EVAR increased to 41.5 (p > 0.05). In like fashion, the rate of STANDARD repairs increased to 41.3 patients per year versus 28.3 before EVAR (p = 0.032). ASA class IV patients increased by almost 9 fold in the recent period versus pre EVAR (p = 0.006). The overall mortality after elective infrarenal AAA repair decreased between the pre and post EVAR periods (6.5% versus 3.7%, p > 0.05) and fell still further to 1.2% in the most recent period (p = 0.021 versus pre EVAR). CONCLUSIONS: The implementation of an EVAR program increases the total volume of AAA repairs but does not reduce open surgical procedures. By allocating patients to EVAR or open repair based their risk factors, mortality was markedly reduced.

Tratamiento endovascular de las lesiones de la aorta torácica: estado actual / Endovascular treatment of thoracic aorta lesions: an update

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New technological developments in the clinical imaging of atherosclerotic plaque.

Direct visualization of the composition of the atherosclerotic plaque during its natural history and after therapeutic intervention may be helpful in detecting lesions with high risk of acute events and in understanding progression and regression of the disease. A wide variety of invasive and non-invasive imaging techniques is available to detect clue aspects of atherosclerosis from the early stage to the clinical evidence appearance. We will firstly review the ongoing technological and clinical research on both invasive and non-invasive techniques. Afterward, we will discuss in detail the use of high-resolution, multi-contrast magnetic resonance imaging for non-invasive imaging of the plaque and its characterization in terms of its various components (i.e., thickness, lipid, fibrous, calcium, or thrombus). Finally, we will describe the potential of quantitative analysis in describing of plaque constituents with improved reproducibility.

Treating complex nervous system vascular disorders through a "needle stick": origins, evolution, and future of neuroendovascular therapy.

In the past few decades, dramatic improvements have occurred in the field of neuroendovascular surgery. Endovascular therapy today is a well-established treatment modality for a variety of cerebrovascular and nonvascular central nervous system diseases. The foundation of this spectacular evolution was laid by the efforts of pioneering visionaries who often worked alone and under difficult, almost impossible, conditions. Ongoing device development and refinement have revolutionized the field at a dizzying, exhilarating pace. With a better understanding of the molecular basis of diseases and further advancements in gene therapy, neuroendovascular techniques have an enormous potential for application to the entire spectrum of central nervous system diseases as a minimally invasive vehicle for the delivery of biological factors.

[Arteriography, endoscopy and periscopy: simultaneous digital imaging]. / Artériographie, endoscopie et périscopie: images simultanées informatisées.

The author reports his personal, limited experience as well as a literature review concerning first results of a simultaneous study of the blood vessels obtained in a similar approach to conventional angiography, but using a digital approach of the vascular lumen, the normal or pathological endothelium, the adventice and/or the perivascular environment. A static and morphologic iconography aims to demonstrate the potential of this imaging approach in the future, especially knowing that those images may be combined to kinetic and/or functional images of the blood circulation.

A method of endoscopic investigation of vascular structures directly through flowing blood.

BACKGROUND: Noninvasive cardiovascular diagnosis has improved immensely due to key technological refinements such as digital subtraction angiography, ultrasonography, Doppler flow analysis, and magnetic resonance imaging. Each of these methodologies provides a unique image of the cardiovascular system but will not permit surgical maneuvers or repairs during real time imaging. Our group has developed a new method of endoscopic visualization of the luminal surface of blood vessels directly through flowing blood without interference of the blood or vessel wall. This opens new possibilities in both diagnosis and surgical interventions. METHODS: Transluminal imaging through flowing blood was performed in normal animals using laser frequency light delivered and retrieved via conventional fiberoptic angioscopic instruments. The reflected light energy was reconstructed into a viewable image using a specialized method of optical data processing and filtering systems. Unlike conventional angioscopy, displacement of flowing blood was not needed as the images were obtained with higher frequency laser light. RESULTS: A total of 20 canine experiments were performed between 1996 and 1997 using our endoluminal imaging system. The images obtained revealed details of luminal surfaces, although primitive and low resolution with this first generation of technology. Images of the topography of the femoral, axillary, and subclavian arteries and veins, as well as several intracardiac structures (aorta and aortic valve) were successfully obtained without trauma or physiologic consequence to the animal. CONCLUSIONS: Using conventional fiberoptic angioscopes coupled with laser light of differing wavelengths, it was possible to image the interior of vascular structures through flowing blood. This method visualizes the intraluminal surface in real time and is dependent only on the delivery and capacity of the endoscope. The implications for future cardiovascular diagnosis and corrective surgical procedures are widespread.