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.