FROM THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
The sinus of Valsalva segment can be preserved during aortic valve replacement irrespective of the type of valve pathology, according to a recent study by Rita Karianna Milewski, MD, and her colleagues at the Hospital of the University of Pennsylvania, Philadelphia.
Severe aortic root dilation coupled to aortic valve disease requires root replacement in patients with a tricuspid or bicuspid aortic valve. Commonly, an aortic valve replacement and supracoronary ascending aorta replacement (AVRSCAAR) procedure has been used for patients who have a mild to moderately dilated sinus segment. One advantage of the procedure is that it retains the sinus of Valsalva (SOV) and preserves the intact coronary ostia.
However, the long-term behavior and risk of aortic events for the retained SOV in both BAV and TAV patients remains unclear, according to Dr. Milewski and her colleagues.
Previous researchers have suggested that patients with BAV and TAV have different rates of complications of the remaining aorta and dilation of the proximal aorta and retained sinus segment. In addition, it has been suggested that the cause of aortic dilation is different in patients with aortic stenosis (AS) and aortic insufficiency (AI) and is based on TAV and BAV morphology, histology, and hemodynamic flow patterns.
However, in the August issue of the Journal of Thoracic and Cardiovascular Surgery, Dr. Milewski and her colleagues reported on their study showing that, in patients with nonaneurysmal SOV undergoing AVRSCAAR, the sinus of Valsalva segment can be preserved regardless of the type of valvular pathology (aortic stenosis vs. aortic insufficiency) or valvular morphology (BAV vs. TAV).
The researchers retrospectively reviewed a prospectively maintained institutional database to stratify all patients by BAV or TAV valvular pathology with concomitant ascending aortic aneurysm who underwent an elective AVRSCAAR from 2002 to 2015 ( J Thorac Cardiovasc Surg. 2017;154:421-32 ).
The distribution of the 428 patients meeting inclusion criteria by subgroups was: BAV group (254 patients: BAV-AS = 178; BAV-AI = 76); TAV group (174 patients: TAV-AS = 61; TAV-AI =113). Preoperative sinus of Valsalva dimensions were divided into 3 subgroups (less than 40 mm, 40-45 mm, and greater than 45 mm).
The mean patient age for patients with BAV and TAV was 59 years and 72 years (P less than .001), respectively (with 78% with BAV being men and 57% with TAV being men). There was a significantly higher subpopulation of AS in the BAV cohort vs. TAV-AS (70% vs. 35%; P less than .001).
With regard to SOV sizing, there was no significant difference in mean preoperative aortic root diameters between BAV and TAV cohorts for the AS or AI subpopulations.
In-hospital/30-day mortality was significantly higher in patients with TAV (5.2%) than in patients with BAV (1.6%, P = .033). In addition, the incidence of transient ischemic attack/stroke was significantly higher in the TAV group (3.4%) vs. the BAV group (0.8%, P = .04).
Valvular morphology and pathology at baseline, preoperative SOV diameter, postoperative time course, and interaction effect of preoperative SOV diameters and postoperative time course were used as covariates to assess outcomes. Within-subject and within–stratified subgroup comparison failed to show main effects across the follow-up times on postoperative SOV size patterns (P = .935), implying that the SOV trends were stable and sustained (discharge to greater than or equal to 10 years) irrespective of valvular morphology and pathology (BAV-AI, BAV-AS, TAV-AI, and TAV-AS).
Preoperative SOV dimensions significantly affected the retained postoperative sinus dimensions (P less than .001), according to Dr. Milewski and her colleagues.
The data indicated that an initial and pronounced postoperative decrease in SOV dimensions occurs with AVRSCAAR independently of aortic valve morphology, aortic valve pathology, and age, they added.
The 10-year freedom from aortic reoperation rates were 97% and 95% in the BAV and TAV subgroups, respectively. The BAV group had significantly improved reoperation-free survival, compared with the TAV group (P less than .001), while the type of valvular pathology within each group did not show a significant survival difference.
“Irrespective of the aortic valve morphology or valve pathology, in patients with mild to moderate aortic root dilatation (less than 45 mm), preservation of the SOV segment in the context of an AVRSCAAR procedure is justified. Continued further follow-up will be important to understand the long-term outcomes of sinus preservation, especially in the younger population with BAVs,” the researchers concluded.
The authors reported having no financial conflicts to disclose.
