Posterior Root Enlargement Research Articles

Aortic Root Enlargement During Aortic Valve Replacement: Nicks and Manouguian Techniques

Aortic valve replacement can be complicated by a small aortic annulus necessitating the placement of an undersized prosthetic valve. In an effort to avoid prosthesis-patient mismatch, root enlargement techniques have been utilized. Herein is a review of the Manouguian and Nicks techniques for posterior root enlargement.

Long-term results of aortic valve replacement with posterior root enlargement

Posterior root enlargement provides the implantation of suitable-sized prosthetic valves in patients with a small aortic root. The aim of this study was to evaluate the long-term results of posterior root enlargement in patients undergoing aortic valve replacement. Between 1997 and 2011, 103 patients with a small aortic annulus (indexed effective orifice area < 0.75 cm(-2) · m(-2)) underwent aortic valve replacement with posterior aortic root enlargement. Forty-six (44%) patients were male. The mean age was 28.62 ± 18.56 years. Survivors were followed up for a mean of 45.6 ± 32.4 months. Early mortality was 9.6%. The most common cause of early mortality was low cardiac output syndrome (6 patients). There were 2 (1.9%) late deaths due to cerebrovascular events. During the follow-up period, mild paravalvular leakage occurred in only one (1%) patient, and one suffered a malfunction of the prosthesis. A significant reduction was seen in the peak pressure gradients across the replaced aortic valves (p < 0.001). Moreover, a significant increase was noted in left ventricular ejection fraction (p = 0.001). Aortic root enlargement using the Manouguian technique can be applied with acceptable safety. It effectively decreases postoperative gradients and increases left ventricular ejection fraction. Short- and long-term mortality and morbidity rates are satisfactory.

Left Ventricular Outflow Tract to Left Atrial Fistula After Aortic Valve Replacement

a posterior root enlargement to avoid patient prosthesis mismatch. The perioperative transesophageal echocardiography (TEE) showed only trace aortic regurgitation (AR) with no other abnormal findings. While the patient had been doing well during the postoperative period, he described palpitation episodes for 10 days. He had no fever or other constitutional symptoms. His examination revealed a normal prosthetic valve sound, 2/6° apical systolic murmur, and his other systemic findings were un-

Posterior Root Enlargement for Aortic Valve Replacement Associated with Unexpected Anomalous Right Coronary Artery

Anomalous right coronary artery (ARCA) generally follows a course between the aorta and pulmonary artery. When ARCA follows a course posterolateral to the aortic root behind the noncoronary sinus of Valsalva, the vessel can be at risk of injury during posterior aortic root enlargement. We present the case of a 21-year-old man with congenital aortic stenosis and small aortic root, who had an intraoperative diagnosis of ARCA. After posterior root enlargement through the noncoronary sinus, ARCA was mobilized from the aortic root and reimplanted into the right coronary sinus. Postoperative follow-up of the patient was uneventful.

Aortic root enlargement: What are the operative risks?

Despite concern that small aortic valve prostheses can lead to prosthesis-patient mismatch with diminished left ventricular mass regression and poor long-term outcome after aortic valve replacement, there remains reluctance to perform aortic root enlargement procedures. We therefore examined the operative risks of aortic valve replacement with and without root enlargement. We reviewed perioperative outcomes among patients undergoing aortic valve replacement at our institution between January 1993 and December 2001. Risk factors for operative death were evaluated by means of multivariable analysis. Of 2366 patients undergoing aortic valve replacement with (1173) or without (1193) concomitant procedures, 249 (10.5%) underwent posterior root enlargement. Patients undergoing complex root enlargement (Konno-Rastan procedures) were excluded. Patients undergoing aortic root enlargement were significantly younger, twice as often female, and more often undergoing a reoperation but were similar with respect to functional class. The mean valve implant size was less in the aortic root enlargement group (21.5 +/- 1.6 vs 23.2 +/- 2.3 mm, P < .0001). As expected, mean crossclamp time and bypass time were somewhat longer with root enlargement. Raw operative mortality was higher with aortic root enlargement (5.6% vs 2.9%, P = .0324); however, by means of multivariable analysis, advanced functional class (P = .0020; odds ratio, 1.87), preoperative congestive heart failure (P < .0001; odds ratio, 3.22), and smaller valve implant size (P = .012; odds ratio, 1.16), but not aortic root enlargement, were independent risk factors for operative death. Aortic root enlargement itself does not increase operative risk, although it is most often required among high-risk patients. Surgeons should not be reluctant to enlarge the aortic root to permit implantation of adequately sized valve prostheses.

Does Aortic Root Enlargement Impair the Outcome of Patients With Small Aortic Root?

Posterior root enlargement procedures provide the implantation of suitable-sized prosthetic valves in patients with a small aortic root to prevent a high postoperative transvalvular gradient. The aim of this study was to evaluate long-term results of the posterior root enlargement. Between 1985 and 2002, 124 patients underwent aortic valve replacement with a posterior root enlargement. The main indication was a small aortic valve orifice area to patient body surface area (indexed valve area < 0.85 cm2/m2). Fifty-four (44%) patients were male, and 70 (56%) were female with a mean age 39.1 +/- 14.3 years. Indications for operation were severe calcified aortic valve stenosis (37.1%), severe aortic insufficiency (25.8%), or combination (37.1%). Seventy-five (60%) patients received double-valve replacement. A pericardial patch was used in 100 patients (80.6%) and a Dacron patch was used in 24 patients. Operative mortality was 6.4% (8 patients). The causes of hospital mortality were low cardiac output syndrome (LCOS) (in 6 patients), cerebrovascular events (in 1 patient) and multiple organ failure (in 1 patient). Multivariate analysis demonstrated concomitant coronary revascularization to be a significant (p = 0.03) predictor for early mortality. There were six (5.4%) late deaths. Cox proportional hazards regression analysis demonstrated LCOS (p = 0.013) and infective endocarditis (p = 0.003) to be significant predictors for late mortality. Atrioventricular block required a permanent pacemaker was observed in 4 patients (3.2%). Posterior aortic root enlargement techniques can be easily applied without additional risks. Long-term survival and freedoms from valve-related complications are satisfactory.

The Konno aortoventriculoplasty for repeat aortic valve replacement.

To evaluate the outcome of aortic root augmentation by the Konno-aortoventriculoplasty technique as part of reoperative aortic valve replacement. Since 1983, 15 patients, 12 males and three females, had repeat aortic valve replacement (AVR) with concomitant Konno aortoventriculoplasty. Age ranged from 1.2 to 18 years (mean 12.5 years). The underlying anatomic diagnoses were valve and subvalvar aortic stenosis in 11, truncal valve insufficiency in one, endocarditis in one, Shone's complex in one and severe aortic insufficiency associated with a ventricular septal defect in one patient. All patients had had previous AVR. The causes for reoperation were prosthetic valve stenosis due to growth in ten and paravalvular leak in one, homograft failure in two, xenograft failure in one, and left ventricular outflow tract obstruction (LVOTO) after mitral valve replacement in one patient. The mean size of explanted prostheses was 19.2 mm (13-23 mm) while the mean size of the implanted prostheses was 24.3 mm (19-27 mm) (P<0.01). Previous aortic root enlargement had been performed in 11 patients in conjunction with AVR. The Manougian technique was used previously in two, Konno aortoventriculoplasty in eight, and both techniques in one patient. The newly implanted aortic valves were a homograft in one patient and mechanical prostheses in 14 patients. There was one operative death (1 of 15 or 6.6%) in a 17.5 year old patient with previous AVR and posterior root enlargement, due to low cardiac output state. Follow-up ranged from 6 months to 17 years (mean 7.2 years). The only late death occurred in an 11.6-year-old patient due to prosthetic valve endocarditis. Two patients had complete heart block and had permanent pacemaker insertion (2 of 15 or 13.3%). One patient had pulmonary valve replacement because of combined stenosis and insufficiency 5 years after operation. All 13-surviving patients are asymptomatic at latest follow up. Konno aortoventriculoplasty with repeat AVR may be safely performed. Excellent results may be achieved despite previous aortic root enlargement. It is a good surgical option for complex LVOTO and may even reduce reoperation in children by allowing placement of a larger prosthesis.