Discussion
Patient′s age and activity can be considered for calculating cardiac output demand; young people with active life style will require larger prosthesis for a higher cardiac demand. Since implanting a small-sized valve can worsen outcome due to increased preload [2]. This study was undertaken to review our strategy and feasibility of ARE in patient undergo DVR to avoid PPM without increase in morbidity or mortality especially in young patients (age = 35± 20).
In patients with a small AA, it is difficult to implant large valve prostheses. PPM is the immediate consequence of this situation[6] . We observed high variable pressure gradient across aortic prosthesis with DVR alone (postoperative PG 25.9 ± 5.8).
Rheumatic heart diseases usually affect left heart valves requirement DVR. Small aortic annulus is a big problem facing cardiac surgeons in AVR and more with DVR. Most of the patients also have tricuspid valve disease, atrial fibrillation and severe LV dysfunction, that add risk factors on hemodynamics if ARE did not performed. So, there is still debated whether implant small prosthesis or ARE to avoid increasing morbidity or mortality. [9] . In our study, preoperative risk factors were not obstacles to do ARE, however, these factors may be worse with PPM.
ARE techniques can be performed simply and modified without complexity to get benefit and avoid complications. So, that is an alternative to implantation of too small prosthesis, ARE may actually reduce mortality[10] . Our study used to perform modified Nick′s procedure to implant larger prosthesis without increasing risk of technique even in junior surgeons.
There have been only a few studies on DVR with ARE. Some with only small number of patients of non-Rheumatic etiology and most are case reports. ARE in DVR is enlarging AA without increase in operative mortality but at expense of prolonged CPB time [10] . That is encouraging us to collect data for comparison between two groups of DVR with/out ARE, and motivate cardiac surgeons to ARE, if needed to avoid PPM. ARE itself does not increase operative risk. Surgeons should not be reluctant to enlarge the aortic root to permit implantation of adequately sized valve prostheses.
ARE requires some technical skills, and should not increase operative risk. So, it is possible to implant valve 2 sizes larger than the native annulus [4] . We observed in the study no incremental risk in mortality or adverse events after surgical ARE compared with AVR alone.
Most surgeons prefer to use a small aortic prosthesis instead of expanding the annulus. Yet the use of a small aortic prosthesis may be associated with obstruction of left ventricular output, resulting in a higher PG and PPM. Studies have demonstrated that mortality was higher in patients receiving a small aortic prosthesis [11] . So, ARE is a safe procedure with expert surgeon and should be considered at the time of AVR even with DVR to avoid PPM.
Surgical ARE has not been widely performed by cardiac surgeons, because of concerns regarding the possible increased risk of early mortality and morbidity [4] . In our study, ARE was safe and did not increase morbidity and mortality.
Conclusion: - Aortic root enlargement can be safely done in patients undergoing double valve replacement with benefit of bigger size prosthesis without additional mortality and morbidity.
Abbreviations:- ARE : aortic root enlargement, DVR : double valve replacement, AV : aortic valve, AVR : aortic valve replacement, AA : Aortic Annulus, NCC : Non Coronary Cusp, LCC : Left Coronary Cusp, LV : Left Ventricle, RHD : rheumatic heart disease, PPM : Prosthesis Patient Mismatch, EOA/i : Effective Orifice Area/ indexed, RHD : Rheumatic Heart Disease, BSA : Body Surface Area, PG : Pressure Gradient, EF : Ejection Fraction, CPB : Cardio Pulmonary Bypass, Ao. /CC time: Aortic Cross Clamp/ time, MV : Mechanical Ventilation, HB : Heart Block, LCO : Low Cardiac Output, COPD : Chronic Obstructive Pulmonary Disease, CAD : Coronary Artery Disease,DM : Diabetes Mellitus, HTN : Hypertension, AF : Atrial Fibrillation, AS : Aortic Stenosis.
Table (1):- Demographic data, pre-operative risk factors.