Day 2 :
Keynote Forum
Hatem H. AlMasri
King Abdulaziz Medical City, Saudi Arabia
Keynote: The outcomes of atrial fibrillation (AF) between Cut and Sew Technique for the Cox-maze Procedure & Comparison with Bipolar Radiofrequency Ablation
Time : 10:00-10:45
Biography:
Al-Masri H Hatem is a cardiac critical care intensivist and consultant of cardiac surgery. He completed his medical degree (MD-Doktorate) at Charles University – Faculty of Medicine and holds a degree in Biochemistry from the University of Waterloo – Canada. He completed his residency training in Germany (Leading Facharzt) and holds training fellowships in Cardiac Surgery from IJN KL Malaysia, Switzerland and Canada. He is the author of an award-wining medical research paper titled “Hemodynamic Support Requires Integrated Approach Comparing pl.VAD vs. IABP in Patients Experiencing Left Ventricular Failure” (Best Paper of Young Cardiac Surgeon) at the 8th International Congress of Update in Cardiology and Cardiovascular Surgery (UCCVS 2012) awarded by European Society for Cardiovascular Surgery, World Society of Arrhythmias (WSA) and the Society of Cardiology and the International Academic of Vascular and Endovascular Surgery (ISCP). He is a member of the Medical German Association, Malaysian Medical Association and the Saudi Medical Council.
Abstract:
Background: Persistent atrial fibrillation leaves patients symptomatic and at increased risk of thromboembolism even after otherwise successful cardiac surgery. Majority of the patients who present to us have organic cardiac disorders predisposing to AF, surgery for the underlying lesions alone usually fails to abolish AF, leaving patients symptomatic and at an increased risk of thromboembolism. Effective treatment procedure surgically of atrial fibrillation is cut-and-sew Cox maze procedure which is widely established. The clinical experience using alternate energy sources is with radio-frequency ablation, which uses alternating current to transfer energy to atrial tissue. Success of this technology has led surgeons to apply RF directly to the heart during cardiac surgery. The effectiveness of RF compared with the standard CS maze procedure is not known .We evaluate the impact of radiofrequency ablation technology by direct comparison with the CS technique
Methods: To treat AF secondary to cardiac lesions requiring surgery, we combined a full Cox-maze using RFA procedure in 184 patients simultaneously undergoing valvular procedures (87), repair of congenital anomalies (12), and other procedures (2), including 24 repeat operations between 2012 and 2016. Matched variables were gender, age, New York Heart Association (NYHA) class, AF type, and concomitant mitral valve. Additional variables potentially affecting out-come, including hypertension (RF vs CS) left atrial size, and preoperative duration of AF were similar between groups.
Results: Procedures performed simultaneously with the maze operation were relevant to the diagnoses. Mean aortic crossclamp time varied from 64 to 235 minutes, with bypass time ranging from 91 to 297 minutes. There were three early deaths (2%), no late deaths, and one episode of transient neurological ischemic attack in follow-up ranging from 1 to 4 years, for a total of 184 patients. Postoperative AF disappeared in 110 patients, rhythms were sinus in 95 patients (80%), junctional in 15 (7%), and persistent AF in 15 (14%), each of whom had mitral valve disease. Three patients (2%) who had never been defibrillated. Patients with other underlying pathology had complete recovery of atrial rhythm. After discharge, patients were followed monthly for adjustment of medication, rhythm, signs of myocardial ischemia, and control of anticoagulation. Doppler echocardiography and chest radiography were scheduled for 1, 3, 6, and 12 months after surgery. Among 36 patients without mechanical valves, 45 (85%) with atrial rhythm and contraction have been taken off anticoagulation therapy or electrocardioversion, including 12 who are free of all medication, leaving 20 patients with persistent AF. Rhythms after the combined procedures were sinus, persistent AF or atrial flutter , and the junctional who eventually required atrial pacemaker implantation. Anticoagulation was discontinued only in patients with atrial rhythm and documented contraction 3 to 6 months after reparative surgery. Antiarrhythmics were tapered after anticoagulation was discontinued or after cardiac rhythm was considered stable.
Conclusions: The standard cut and sew Cox-maze procedure remains the gold standard for the surgical treatment of AF. The results suggest that the combined approach is safe, effective, and indicated in patients who are judged capable of tolerating the procedure and likely to regain atrial rhythm .the risk of death, cerebrovascular events, and reoperation for bleeding. Superiority of cut-and-sew technique for the Cox maze procedure in reducing the prevalence of atrial flutter during follow-up, but bipolar RF shortens the aortic cross-clamping time and cardiopulmonary bypass time, and decreases the risk of permanent pacemaker implantation.
Keynote Forum
Azzam A. Maghazachi
University of Sharjah, UAE
Keynote: Updates on Cancer Immunotherapy with Emphasis on Innate Immune Cells
Biography:
Azzam A Maghazachi received a master degree from NYU Medical School and a PhD degree in Immunology from the University of Manitoba/Canada in 1984. Between 1988-2005, he held several senior positions at various institutes and universities in the USA, Canada and Norway. In 2005, he was the director of research at Bio-Quant, Inc. in San Diego, and between 2007-2015 he was a professor of Physiology in the faculty of Medicine at the University of Oslo. Currently, he is a professor at the College of Medicine, University of Sharjah. He published more than 100 papers and book chapters and is an editor or editor-in-chief on more than 15 medical journals.
Abstract:
Cancer immunotherapy protocols represent the most novel exciting therapeutic modality for treating cancer. This is evident in the recent attention paid to checkpoint inhibitors for treating melanomas as well as other forms of cancer. Natural killer (NK) cells stand at the cross road among treatment of autoimmune diseases and immunodeficient diseases. We reported a new mechanism of action for the drug Copaxone (glatiramer acetate or GA; TEVA Inc.). NK cells isolated from patients dosed with GA lysed dendritic cells isolated from the same patients as well killing tumor target cells. Similarly, vitamin D3 or FTY720 (Gilenya; Novartis) augmented IL-2-activated NK cells lysis of tumor cells. Dimethyl fumarate (DMF; Biogen Inc.) is a new drug for treating multiple sclerosis patients. We have examined the effects of DMF and the metabolite monomethyl fumarate (MMF) on various activities of NK cells. We demonstrated that MMF induces resting CD56+ NK cell lysis of the NK-sensitive K562 cells and the NK-resistant RAJI cells. More recently, we observed that GA, MMF and DMF up-regulate the expression of CCR10 on the surface of activated NK cells. This is corroborated with the ability of NK cells to migrate towards the concentration gradients of CCR10 ligands, namely CCL27 and CCL28. These observations are the first to show that drugs used to treat autoimmune diseases can be used to direct the anti-tumor effector cells towards the sites of tumor growth, particularly those secreting the chemokine CCL27 such as melanomas or squamous cell carcinoma, or those secreting CCL28 such as colorectal carcinoma. Hence, drugs used to treat autoimmune diseases can be used to harness NK cells for the purpose of using them in cancer immunotherapy.