Eficacia y seguridad del Láser Coronario en el tratamiento percutáneo de lesiones coronarias complejas / Efficacy and safety of Coronary Laser in the percutaneous treatment of complex coronary lesions

INTRODUCCIÓN: La enfermedad cardiovascular es en Europa la causa de aproximadamente de un tercio de todas las muertes en personas mayores de 35 años. Una gran parte de esta carga de enfermedad es debida a la enfermedad coronaria. El incremento de la esperanza de vida y el envejecimiento poblacional, permite prever un aumento considerable de la incidencia del síndrome coronario agudo (SCA) durante las próximas tres o cuatro décadas. En el diagnóstico y tratamiento de la enfermedad coronaria, la coronario grafía con contraste (CGC) es una pieza central y la revascularización con técnicas percutáneas (ICP) es la forma de tratamiento más frecuente y ofre cemuy buenos resultados en la mayoría de las lesiónes coronarias. Los objetivos de la ICP son la dilatación de la estenosis y la colocación de un stent y requiere, la mayoría de las veces, una actuación previa sobre la placa de ateroma. Existen lesiones coronarias complejas que requieren intervenciones para modificar la placa de ateroma durante el ICP; para ello se emplean, entre otras la ater

Cardiovascular disease in Europe is the cause of approximately one third of all deaths in people over 35 years of age. A large part of this disease burden is due to coronary heart disease. The increase in life expectancy and popula tion aging make it possible to prevent a considerable increase in the inciden ce of acute coronary syndrome (ACS) during the next three or four decades. In the diagnosis and treatment of coronary disease, contrast-enhanced coronary angiography (CGC) is a central piece and revascularization with percutaneous techniques (PCI) is the most frequent form of treatment, offe ring very good results in most coronary lesions. The objectives of PCI are dilation of the stenosis and placement of a stent, and most of the time they require prior action on the atherosclerotic plaque. There are complex coronary lesions that require emergencies to mo dify the atherosclerotic plaque during PCI, for which láser atherectomy is used, among others. Whenever it was possible for the data to be synthesized in the form of a meta-analysis with the help of the Review Manager 5.3 tool, when a poo led analysis was not possible, the results of the different studies were shown individually. AIMS: The objective of this report is to analyze the effectiveness and safety of the use of the coronary láser in the modification of the atherosclerotic plaque within the PCI procedure in different complex scenarios. METHODS: After defining the research questions and assessing the importance of each of them, several bibliographic search strategies were defined for different databases. The searches were mainly aimed at knowing the effectiveness and safety, according to the questions asked. These searches were designed to maximize sensitivity in order to obtain the broadest spectrum of publica tions for each of the clinical situations. Evidence synthesis was performed using the GRADE methodology and the GRADE-Pro tool. Where possible, data from different papers were pooled in meta-analyses with the help of the Review manager v5.2 package, where data from individual papers were shown when not possible. The results and conclusions were agreed upon by all the authors. RESULTS: Given that coronary láser is a complementary technique used in various cli nical situations in the PCI procedure to favorably modify the plaque (or the thrombus in the case of ACS) and achieve revascularization through the subsequent implantation of a stent, the report on the use of láser in the di fferent clinical situations in which it can be useful. Question 1 (Insurmountable or indilatable lesions). An uncrossable lesion was defined as one in which it was impossible to advance through with a microcatheter or a low-profile balloon, even though it was possible to traver se with a guidewire. After the search, five publications were identified that communicated results of case series and that described, almost all, results of the acute period, none of them presented results of a control group. In the analyzed studies, favorable and consistent results have been found between the works, at the same time the adverse results are not very frequent; however, the studies were performed with small samples and neither angiographic nor evolution results were shown. Question 2 (Patients with an indication for PCI in acute coronary syndro me). To resolve this question, it was decided to use controlled studies whose objective was to determine the efficacy or effectiveness of the EXCIMER láser. After an exhaustive process, 3 studies were selected and included in a meta-analysis. All studies evaluate the success of the procedure, defined in a variable way, although a joint estimate of the effect of the EXCIMER láser can be made, showing that patients in the control group suffer a small increased risk of not achieving success RR=1.13 [CI95% 1.03 to 1.25]. Outco mes related to recovery of coronary flow were also evaluated. It seems that patients in the control group could have a higher risk of negative outcome, although it does not reach statistical significance. Regarding complications, their presentation is very similar between both treatment arms, so the risk estimate is practically null RR=0.98 [95% CI 0.52 to 1.84] Question 3 (Patients with an indication for PCI in in-stent restenosis) The search for published evidence allowed us to identify five publications with a controlled case series design that described the results of the intervention in terms of reperfusion, procedure safety and clinical results at more than 6 months. The degree of confidence in terms of the GRADE methodology offered by this evidence is low. No statistically significant differences could be demonstrated in angiographic success (defined as less than 50% residual stenosis obtained after the procedure in the absence of major cardiac com plications) RR=1.02 [CI95% 0.96; 1.07]. A difference could be demonstrated in the proportions of presence of residual stenosis -3.77% [CI95% -7.00%; -0.53%] and no effect was shown on the maximum luminal diameter of the target segment 0.08mm [CI95% -0.02; 0.19] I2 3%. Regarding safety, no sta tistically significant results were shown in two variables analyzed related to the safety of the intervention: hospital discharge without complications and the need for urgent surgery for coronary revascularization. It has also not been possible to demonstrate significant associations between the interven tion performed on the patients and the clinical results during the deferred follow-up (mean follow-up close to 225 days): death, need for coronary in tervention and myocardial infarction. Question 4 (Patients with an indication for PCI due to stent underexpan sion). It was not possible to identify SR or CT whose objective was to eva luate the efficacy, effectiveness or safety of EXCIMER láser compared to the usual procedure (PCI with conventional balloon dilation), for this reason it was decided to identify observational studies that included or did not in clude a control group, although other types of studies were also reviewed. After the selection process, 3 articles were used to answer this question, all of them showed results from small series of cases without a control group. The study of the outcomes is not homogeneous among the three works: the most common of the reports is the proportion of post-procedure stenosis whose reported weighted average is 20.37% [CI95% 11.07%; 33.92%]. The description of the outcomes related to the safety of the procedure is une ven among the three studies, the most commonly described are: AMI 3.6% [95% CI 0.63%; 17.71%] death 0% [CI95% 0% ; 7.86%], myocardial infarc tion 4.2% [CI95% 1.17% ; 14.25%] and coronary perforation 3.8% [CI95% 0.68% ; 18.89%]. Regarding deferred outcomes, beyond the post-procedure period, the different follow-up times and modalities are also described in a very scattered manner: thus, death was calculated as a weighted average of 9.25% [CI95% 4.02%; 19.91%] with mean follow-ups in the range of 3-6 months. The need for deferred revascularization of the treated lesion could be estimated at 3.7% [CI95% 1.02%; 12.53%]. However, the confidence that the included studies allow for the resolu tion of the question is very weak. Question 5: (Patients with an indication for PCI in the saphenous vein graft). After the search, 2 publications were selected: one of them describes the results of an observational study in which patients who required surgery on saphenous vein grafts, excluding patients with recent infarction or elevated CPK-MB, systolic function less than 30% and use planning of a DPD (distal protection device), with the aim of reducing embolic complications in this subgroup of high-risk lesions; the other study included patients with non-ST segment elevation acute coronary syndrome who required saphenous vein graft surgery. Both are controlled observational studies and the degree of confidence they offer is very low. In the study conducted on patients without ACS, the group whose incompetent saphenous vein grafts were treated with láser did not show a significant difference in the rate of restoration of flow, or in graft dissection or perforation, or in other undesirable events, in com parison with rates reported in patients treated without the involvement of EXCIMER láser. In the observational study of conducted on patients with non-ST elevation ACS who underwent DPD or ELCA-assisted PCI. It was not possible to demonstrate significant differences for any of the outcomes studied: reestablishment of flow, periprocedural AMI, and other immediate outcomes after the intervention. Unfortunately, no results are offered for a term greater than 30 days and it is necessary to point out that the evidence provided in this clinical situation is indirect, insofar as this study was not designed to evaluate the efficacy of coronary láser in this clinical situation KEY POINTS Coronary láser could be an effective and safe technique in the percutaneous treatment of complex coronary lesions, although the available evidence does not allow firm conclusions to be drawn on its effectiveness compared to the usual PCI techniques and other techniques proposed for the treatment of atherosclerotic plaque. or the thrombus in the usual technique was insuffi cient to achieve adequate coronary flow. The láser usage scenarios described in the literature usually overlap. In this report, the possible effectiveness has been evaluated in non-crossable and undilatable lesions, stent restenosis, under-expanded stents, calcified lesions, chronic occlusions, acute coronary syndrome and saphenous vein grafts. Higher quality randomized and observational studies are needed to as sess the efficacy and safety of the technique by comparing it with available alternative therapies and evaluating its longer-term results.

Angiographic outcome after intracoronary X-Sizer helical atherectomy and thrombectomy: first use in humans.

The objective of this study was to evaluate the early angiographic outcome in the first human subjects who underwent intracoronary atherectomy and thrombectomy using the X-Sizer helical cutting and aspiration system. Percutaneous coronary interventions in patients with thrombo-occlusive disease or friable degenerative saphenous vein grafts are associated with considerable periprocedural morbidity and mortality, predominantly related to microscopic distal embolization. X-Sizer catheter system is a novel atherectomy and thrombectomy device that consists of a helix cutter connected to a handheld motor drive unit and a vacuum collection chamber for aspiration of excised atheroma, thrombus, and debris. Quantitative coronary angiography was obtained in 14 patients before and after X-Sizer extraction atherectomy with adjunctive balloon angioplasty and stenting. Thirteen native coronary arteries and one saphenous vein graft were treated. Mean preprocedural reference vessel diameter was 3.06 +/- 0.66 mm. There were 71.4% AHA/ACC type B2 and C lesions. Preprocedural thrombus was present in nine patients and total occlusion in 64% of cases. Minimal luminal diameter was increased from 0.29 +/- 0.47 mm to 1.32 +/- 0.64 mm, a gain of 1.04 +/- 0.69 mm after atherectomy. Final total gain was 1.47 +/- 0.61 mm. Mean diameter stenosis was reduced from 89.3% to a final residual stenosis of 14.4%. Postatherectomy distal embolization occurred in one patient who had heavy preprocedural thrombus burden. No episodes of perforation, distal coronary spasm, abrupt closure, or slow/no-reflow occurred. The angiographic analysis of the first cohort of human subjects suggests that X-Sizer helical atherectomy is a feasible method of removing occlusive tissue or thrombus in coronary artery disease with a low angiographic complication rate. A large-scale randomized phase II clinical trial is underway to determine the ultimate safety and efficacy of this device in thrombo-occlusive native coronary arteries and saphenous vein grafts.

[Rotational atherectomy (Rotablator) for percutaneous transluminal coronary angioplasty]. / Aterectomía rotacional (Rotablator) en la angioplastía coronaria percutánea transluminal.

BACKGROUND: The use of Rotablator in percutaneous transluminal coronary angioplasty attempts to reduce the atheromatous plaque abrading it and fragmenting the parietal calcium of the artery. AIM: To report our experience with the use of Rotablator. PATIENTS AND METHODS: Rotational atherectomy was performed in 189 patients aged 60.8 +/- 11 years (154 men). The clinical indication for the procedure was chronic angina in 22%, unstable angina in 44%, myocardial infarction in 21%, silent angina in 7% and re-stenosis in 6%. One hundred seventy seven patients were followed for a mean of 15.9 +/- 6.3 months. RESULTS: Two hundred thirty six stenoses in 215 coronary arteries were treated with a 98.7% angiographic success rate. One patient had a Q infarction and no patient died or required emergency surgery. Fourteen patients had rises in CK MB enzymes (non Q infarction). Three patients had a pseudoaneurism and three had bleedings that required transfusion. Of the followed patients, 33 had a clinically suspected re-stenosis, that was angiographically confirmed in 23. Cardiac mortality was 2.3%. Seventy nine percent of patients had an evolution without angina or coronary events. CONCLUSIONS: Percutaneous transluminal coronary angioplasty with the use of Rotablator had a high immediate success rate and a low incidence of complications. The clinical evolution of patients has been favorable with a low incidence of mortality and ischemic events.

[Coronary artery perforation with rotational coronary atherectomy]. / Perfuração de artéria coronária com rotablator.

The authors describe a rare case of circumflex coronary artery perforation during rotational coronary atherectomy complicated with cardiac tamponade and good outcome. The possible causes of perforation are discussed and the burr oversize (burr/artery ratio was 0.58) was refused. Shortening and artery plicature (accordeon effect) might have been the cause of this event. Quantitative measurement was made in order to strengthen this hypothesis. It is emphasized the importance of selecting lesions that should be submitted to rotational coronary atherectomy.

Perfuração de artéria coronária com rotablator / Coronary artery perforation with rotational coronary atherectomy

The authors describe a rare case of circumflex coronary artery perforation during rotational coronary atherectomy complicated with cardiac tamponade and good outcome. The possible causes of perforation are discussed and the burr oversize (burr/artery ratio was 0.58) was refused. Shortening and artery plicature (accordeon effect) might have been the cause of this event. Quantitative measurement was made in order to strengthen this hypothesis. It is emphasized the importance of selecting lesions that should be submitted to rotational coronary atherectomy

É relatado caso raro de perfuração da artéria circunflexa durante aterectomia rotacional (AR), complicado com tamponamento cardíaco, que evoluiu favoravelmente. São discutidas as prováveis causas, afastando a possibilidade da ocorrência de um superdimensionamento da oliva utilizada (relação de diâmetro oliva-artéria foi de 0,58), e é sugerido o encurtamento e plicatura da artéria (efeito sanfona) como provável causa dessa perfuração. São feitas medidas quantitativas para reforçar essa hipótese, e ressaltam-se os cuidados necessários na escolha das lesões a serem submetidas à ablação com AR

[Directional coronary atherectomy. The initial experience]. / Aterectomia coronária direcional. Experiência inicial.

Four male patients, 38 to 59 years old (mean 49 +/- 2.5), with angina and the angiographic features has been the classical indications for the method, underwent directional coronary atherectomy. Vessels treated were, respectively, left anterior descending artery (LAD), right coronary artery (RCA), saphenous vein graft (SVG) to LAD and SVG to left marginal branch. Reductions to 50% or less of the internal diameter was considered a satisfactory result. Early success was obtained in all four patients. Obstructions of 75 to 95% (mean of 83 +/- 7.5%) were reduced to 0-25% (mean 12 +/- 5%) after atherectomy. Only one patient died suddenly five days after de procedure. So, directional coronary atherectomy may represent a reliable and safe method for special situations.

Aterectomia coronária direcional: experiência inicial / Directional coronary atherectomy: the initial experience

Four male patients, 38 to 59 years-old (mean 49 ± 2.5), with angina and the angiographic features has been the classical indications for the method, underwent directional coronary atherectomy. Vessels treated were, respectively, left anterior descending artery (LAD), right coronary artery (RCA), saphenous vein graft (SVG) to LAD and SVG to left marginal branch. Reductions to 50 % or less of the internal diameter was considered a satisfactory result. Early success was obtained in all four patients. Obstructions of 75 to 95% (mean of 83 + 7.5°/O) were reduced to 0-25% (mean 12 ± 5%) after atherectomy. Only one patient died suddenly five days after de procedure. So, directional coronary atherectomy may represent a reliable and safe method for special situations

Quatro pacientes, do sexo masculino, com idades entre 38 a 59 (média = 49 ± 2,5) anos, com angina de peito e as características angiográficas enquadrandose nas indicações atuais do método utilizado, realizaram aterectomia oronária direcional. Os vasos dilatados foram coronária descendente anterior, coronária direita, ponte de safena para a coronária descendente anterior e ponte de safena para o 2° ramo marginal da artéria coronária circunflexa. Resultado satisfatório, após a realização do procedimento, foi considerado a redução da obstrução a valores menores ou iguais a 50 %. O sucesso inicial da aterectomia coronária foi observado em todos os pacientes. O grau de obstrução dos vasos abordados reduziu-se de 75 - 95% (média de 83 7,5%) para 0-25% (média de 12 ± 5%) pós aterectomia. Apenas um paciente faleceu subitamente no 5° dia. Assim, a aterectomia coronária direcional, em situações específicas, parece ser um procedimento eficaz e seguro