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Dive into the research topics where Michalis Argiriou is active.

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Featured researches published by Michalis Argiriou.


The Journal of Thoracic and Cardiovascular Surgery | 2014

Endovascular repair for blunt thoracic aortic injury: 11-year outcomes and postoperative surveillance experience

Konstantinos Spiliotopoulos; John Kokotsakis; Michalis Argiriou; Panagiotis Dedeilias; Dimosthenis Farsaris; Theodore Diamantis; Christos Charitos

OBJECTIVE Surveillance for patients undergoing thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI) varies. Annual chest computed tomographic angiography (CTA) is often recommended but concerns about the risks and costs have emerged. The aim of this study was to examine the optimal follow-up frequency based on 11-year outcomes and surveillance experience. METHODS Seventy-six patients with BTAI received TEVAR from May 2002 to July 2013. Demographics, cardiovascular risk factors, Injury Severity Score (ISS), types, sizes, timing, and outcomes of stent grafts were collected retrospectively. RESULTS Mean age was 39.7 years (range, 17-85 years); 8 (11%) were women. Mean ISS was 46.2 ± 18.5 (deceased, 61.0 ± 19.2; surviving, 44.2 ± 17.6; P = .023). Technical success was achieved in 71 patients (93.4%). All-cause mortality was 7 (9.2%), 1 (1.3%) of which was related to the procedure. Six were lost to follow-up (8%). To examine the effect of surveillance frequency on outcomes, after excluding the 2 most recent (<1 year) surviving patients, we arbitrarily divided the remaining 61 with stable repairs based on the timing of their follow-up: 36 underwent timely follow-up (within ± 6 months of the scheduled annual visit; clinical examination, CTA, magnetic resonance angiography, and echocardiography); 25 had delayed follow-up (>6 months after scheduled annual visit). No significant differences were found for survival, graft-related complications, need for reintervention, except for postoperative hypertension, which was higher in the first group. All surviving patients had excellent outcomes, with no cerebrovascular accidents, paraplegia, or paraparesis; the median follow-up for both groups was 3 years (interquartile range 2.0-3.5, 1.5-5.4 years). CONCLUSIONS Midterm outcomes of TEVAR for patients with stable repair after BTAI are excellent, both with timely (1.0-1.5 years) and delayed (>1.5 years) follow-up intervals after a median surveillance period of 3 years. A larger prospective randomized study could lead to a more relaxed, but equally safe surveillance schedule for these patients, lowering risks and costs.


Annals of Cardiac Anaesthesia | 2015

Mechanisms of oxidative stress and myocardial protection during open-heart surgery.

Nikolaos G. Baikoussis; Nikolaos A. Papakonstantinou; Chrysoula Verra; Georgios Kakouris; Maria Chounti; Panagiotis Hountis; Panagiotis Dedeilias; Michalis Argiriou

Cold heart protection via cardioplegia administration, limits the amount of oxygen demand. Systemic normothermia with warm cardioplegia was introduced due to the abundance of detrimental effects of hypothermia. A temperature of 32–33°C in combination with tepid blood cardioplegia of the same temperature appears to be protective enough for both; heart and brain. Reduction of nitric oxide (NO) concentration is in part responsible for myocardial injury after the cardioplegic cardiac arrest. Restoration of NO balance with exogenous NO supplementation has been shown useful to prevent inflammation and apoptosis. In this article, we discuss the “deleterious” effects of the oxidative stress of the extracorporeal circulation and the up-to-date theories of “ideal” myocardial protection.


Journal of Cardiology | 2017

Cardiac surgery or interventional cardiology? Why not both? Let's go hybrid

Nikolaos A. Papakonstantinou; Nikolaos G. Baikoussis; Panagiotis Dedeilias; Michalis Argiriou; Christos Charitos

A hybrid strategy, firstly performed in the 1990s, is a combination of tools available only in the catheterization laboratory with those available only in the operating room in order to minimize surgical morbidity and face with any cardiovascular lesion. The continuous evolution of stent technology along with the adoption of minimally invasive surgical approaches, make hybrid approaches an attractive alternative to standard surgical or transcatheter techniques for any given set of cardiovascular lesions. Examples include hybrid coronary revascularization, when an open surgical anastomosis of the left internal mammary artery to the left anterior descending coronary artery is performed along with stent implantation in non-left anterior descending coronary vessels, open heart valve surgery combined with percutaneous coronary interventions to coronary lesions, hybrid aortic arch debranching combined with endovascular grafting for thoracic aortic aneurysms, hybrid endocardial and epicardial atrial fibrillation procedures, and carotid artery stenting along with coronary artery bypass grafting. The cornerstone of success for all of these methods is the productive collaboration between cardiac surgeons and interventional cardiologists. The indications and patient selection of these procedures are still to be defined. However, high-risk patients have already been shown to benefit from hybrid approaches.


Annals of Cardiac Anaesthesia | 2016

Perceval S aortic valve implantation in an achondroplastic Dwarf

Nikolaos G. Baikoussis; Michalis Argiriou; Orestis Argiriou; Panagiotis Dedeilias

Despite cardiovascular disease in patients with dwarfism is not rare; there is a lack of reports referring to cardiac interventions in such patients. Dwarfism may be due to achondroplasia or hormonal growth disorders. We present a 58-year-old woman with episodes of dyspnea for several months. She underwent on transthoracic echocardiography, and she diagnosed with severe aortic valve stenosis. She referred to our department for surgical treatment of this finding. In accordance of her anthropometric characteristics and her very small aortic annulus, we had the dilemma of prosthesis selection. We decided to implant a stentless valve to optimize her effective orifice area. Our aim is to present the successful Perceval S valve implantation and the descriptions of the problems coming across in operating on these special patients. To our knowledge, this is the first case patient in which a Perceval S valve is implanted according to the international bibliography.


Open Access Macedonian Journal of Medical Sciences | 2016

Aortic Root Enlargement or Sutureless Valve Implantation

Nikolaos G. Baikoussis; Panagiotis Dedeilias; Michalis Argiriou

Aortic valve replacement (AVR) in patients with a small aortic annulus is a challenging issue. The importance of prosthesis–patient mismatch (PPM) post aortic valve replacement (AVR) is controversial but has to be avoided. Many studies support the fact that PPM has a negative impact on short and long term survival. In order to avoid PPM, aortic root enlargement may be performed. Alternatively and keeping in mind that often some comorbidities are present in old patients with small aortic root, the Perceval S suturelles valve implantation could be a perfect solution. The Perceval sutureless bioprosthesis provides reasonable hemodynamic performance avoiding the PPM and providing the maximum of aortic orifice area. We would like to see in the near future the role of the aortic root enlargement techniques in the era of surgical implantation of the sutureless valve (SAVR) and the transcatheter valve implantation (TAVI).


Annals of Cardiac Anaesthesia | 2016

Iatrogenic dissection of the descending aorta: Conservative or endovascular treatment?

Nikolaos G. Baikoussis; Michalis Argiriou; Theodoros Kratimenos; Vasiliki Karameri; Panagiotis Dedeilias

Transcatheter aortic valve implantation (TAVI) is without any doubt a standard technique and the treatment of choice of severe aortic valve stenosis (AVS) in very high-operative risk patients. However, a number of complications may occur and has been described. Improper valve position, valve migration, paravalvular regurgitation, conduction disturbances, stroke and aortic dissection have been succeeded despite the perfection of the technique. For anyone of the complications above described, a solution may be invented. We present an interesting case of an 81-year-old woman with severe AVS treated through TAVI due to very high operative risk. This female, 12 days later presented with thoracic pain and shortness of breath and through the computed tomography of the chest performed was diagnosed a dissection of the descending aorta. She successfully underwent on thoracic endovascular aortic repair. In this report, we refer the bibliographic data and we discuss the treatment options in these cases.


Annals of Cardiac Anaesthesia | 2015

Lipomatous hypertrophy of the interatrial septum and fibrosing mediastinal lymphadenopathy causing superior vena cava obstruction.

Nikolaos G. Baikoussis; Orestis Argiriou; Theodoros Kratimenos; Panagiotis Dedeilias; Michalis Argiriou

Lipomatous hypertrophy of the interatrial septum (LHIS) is an uncommon cause of superior vena cava syndrome (SVCS). Fibrosing mediastinal lymphadenopathy is another cause of SVCS. We present a 65-year-old female patient with a history of tuberculosis (TB) and the coexistence of LHIS and fibrosing mediastinitis due to TB of the lung. Fibrosing or sclerosing mediastinitis is a rare entity with few cases published in the western literature. She presented with mild symptomatology of SVCS and she underwent on transthoracic and transesophageal echocardiography, computed tomography scan, magnetic resonance imaging, and venography. Due to the development of an abundant collateral venous system seen on venography and her negation for any treatment, she did not undergo yet on any intervention. To our knowledge, this is the first case reported in the international bibliography in which LHIS and sclerosing lymphadenopathy are simultaneously diagnosed in the same patient.


The Annals of Thoracic Surgery | 2018

Stentless Aortic Bioprosthetic Valves and Placement of Radiopaque Markers

Niki Lama; Vasileios Patris; Petros Maniatis; Michalis Argiriou

M IS C E L L A N E O U S 2. Pettersen Ø, Haram PM, Winnerkvist A, et al. Pedicled vein grafts in coronary surgery: perioperative data from a randomized trial. Ann Thorac Surg 2017;104:1313–7. 3. Souza D. A new no-touch preparation technique. Technical notes. Scand J Thorac Cardiovasc Surg 1996;30:41–4. 4. Pettersen Ø, Wiseth R, Hegbom K, Nordhaug DO. Pedicled vein grafts in coronary surgery exhibit reduced intimal hyperplasia at 6 months. J Am Coll Cardiol 2016;68:427–9.


Journal of Vascular Surgery | 2018

Repair of descending thoracic aortic aneurysms with Ankura Thoracic Stent Graft

Theodoros Kratimenos; Constantine N. Antonopoulos; Dimitrios Tomais; Panagiotis Dedeilias; Vasileios Patris; Ilias Samiotis; John Kokotsakis; Dimosthenis Farsaris; Michalis Argiriou

Objective The aim of the study was to present the results for patients with atherosclerotic aneurysm of the descending thoracic aorta (DTA) treated with a novel thoracic stent graft. Methods A single‐center retrospective review of prospectively collected data was performed. We extracted demographic variables as well as atherosclerotic comorbidities and operation‐related and imaging‐related data from patients’ medical records. We estimated technical success rate, in‐hospital and 30‐day mortality, and mortality at the end of follow‐up as well as complication and reintervention rate in our study cohort. Follow‐up computed tomography angiography was performed after 1 month and 6 months and yearly thereafter. Results A total of 30 patients (80% male; mean age, 73.7 ± 6.33 years) were treated with Ankura Thoracic Stent Graft (Lifetech, Shenzhen, China) for DTA aneurysm from February 2014 until June 2017. Technical success of the thoracic endovascular aortic repair (TEVAR) was 97% (29/30 patients). A surgical conduit was required in one patient; in three patients, we intentionally covered the left subclavian artery because of insufficient proximal landing zone. No aorta‐related deaths were recorded during follow‐up. During the early postoperative period, two patients (7%) with long DTA coverage developed paralysis or paraparesis, which immediately resolved after lumbar drainage. No renal complications requiring dialysis were observed. One patient (3%) developed postoperative pulmonary infection, whereas access site complications were 7%. Two symptomatic patients treated outside instructions for use (7%) developed early type IA endoleak and one patient (3%) developed type IB endoleak; type II endoleak was recorded in 3% of the study cohort. During the 30‐day postoperative period, two patients died of non‐TEVAR‐related causes, one of gastrointestinal bleeding and the other of pulmonary infection. During a median follow‐up of 31.7 (range, 38.4) months, two more patients also died of non‐TEVAR‐related causes, one of stroke from carotid artery disease and the other of motor vehicle trauma. In the rest of the cohort, no other adverse events were noted. Conclusions This novel endograft showed early evidence of a safe, effective, and durable endoprosthesis for the treatment of DTA aneurysms.


Journal of Thoracic Disease | 2018

Antegrade cardioplegia as a possible cause of acute saphenous vein endothelial damage in patients undergoing on pump coronary artery bypass surgery

Ioannis Koukis; Stavros Siminelakis; Michalis Argiriou; Nikolaos Theakos; Anna Takou; George Pounis; Christos Charitos; Efstratios Apostolakis

Background The administration of antegrade cardioplegia through vein grafts after the completion of each distal anastomosis is a common practice. However, the cardioplegic solution may disrupt the vein endothelium and contribute to late vein graft atherosclerotic disease. This study aimed at evaluating the possible impact of the cardioplegic solution on vein graft endothelium. Methods Total of 52 patients (16 women and 36 men) aged 68±8.5 years old that underwent on pump coronary revascularization with at least one vein graft were enrolled. Sections of grafts from the greater saphenous vein were obtained prior to and after delivery of potassium antegrade cardioplegic solution through them. These sections were then examined histologically with immunochemical stain and CD34 index. The endothelial damage and length of vein specimens of both graft sections were evaluated. Results The endothelial damage of vein specimens appeared to be increased significantly with exposure to antegrade cardioplegia in male and female patients (P from Wilcoxon tests <0.001, for both genders). The increase in the length of vein specimens was significant too (P from Wilcoxon test <0.001 for men and P=0.001 for women). Conclusions Antegrade cardioplegia delivered through vein grafts causes substantial damage on vein endothelium. This may have an adverse effect on long-term graft patency.

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Panagiotis Dedeilias

National Technical University of Athens

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Christos Charitos

National and Kapodistrian University of Athens

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D Niakas

Hellenic Open University

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