Interposition Technique for Pulmonary Valve Replacement.

BACKGROUND: Stented bioprosthesis implant at surgical pulmonary valve replacement (PVR) ideally should be 25 to 27 mm to facilitate future percutaneous PVR. This often requires accommodating 35 to 37 mm diameter sewing ring in the pulmonary position and requires anterior patch augmentation of the right ventricular outflow tract (RVOT). We present a novel "interposition" technique of PVR that allows upsizing the valve without RVOT patch augmentation. METHODS: Using standard cardiopulmonary bypass, the main pulmonary artery (MPA) is dissected and transected at an appropriate level. The remnants of pulmonary valve leaflets are excised. The valve stent posts are telescoped into distal MPA, the MPA continuity is restored by end-to-end anastomosis of the proximal and distal MPA, with the interposed prosthetic valve sewing ring in the suture line between the two edges of the MPA with the bulk of the sewing ring extravascular. RESULT: A total of seven patients (tetralogy of Fallot, three; congenital pulmonary stenosis, four; age range: 15-33 years) underwent the procedure. No patient required RVOT patch augmentation, all patients were extubated in the operating room and were fast-tracked to recovery. Our proposed technique of PVR has the following advantages: accommodate larger size valve, eliminates risk of a paravalvar leak, coronary compression, and anterior tilting of the prosthesis. CONCLUSION: The valve interposition technique avoids the need for RVOT patch, allows implantation of an adequate sized prosthetic valve, maintains native geometry of the pulmonary artery without the risk of tilting of the prosthesis, and eliminates the risk of paravalvular regurgitation and left coronary compression.

Surgical pericardial adhesions do not preclude minimally invasive epicardial pacemaker lead placement in an infant porcine model.

BACKGROUND: Pericardial adhesions in infants and small children following cardiac surgery can impede access to the epicardium. We previously described minimally invasive epicardial lead placement under direct visualization in an infant porcine model using a single subxiphoid incision. The objective of this study was to assess the acute feasibility of this approach in the presence of postoperative pericardial adhesions. METHODS: Adhesion group piglets underwent left thoracotomy with pericardiotomy followed by a recovery period to develop pericardial adhesions. Control group piglets did not undergo surgery. Both groups underwent minimally invasive epicardial lead placement using a 2-channel access port (PeriPath) inserted through a 1 cm subxiphoid incision. Under direct thoracoscopic visualization, pericardial access was obtained with a 7-French sheath, and a pacing lead was affixed against the ventricular epicardium. Sensed R-wave amplitudes, lead impedances and capture thresholds were measured. RESULTS: Eight piglets underwent successful pericardiectomy and developed adhesions after a median recovery time of 45 days. Epicardial lead placement was successful in adhesion (9.5 ± 2.7 kg, n = 8) and control (5.6 ± 1.5 kg, n = 7) piglets. There were no acute complications. There were no significant differences in capture thresholds or sensing between groups. Procedure times in the adhesion group were longer than in controls, and while lead impedances were significantly higher in the adhesion group, all were within normal range. CONCLUSIONS: Pericardial adhesions do not preclude minimally invasive placement of epicardial leads in an infant porcine model. This minimally invasive approach could potentially be applied to pediatric patients with prior cardiac surgery.

Modified Damus-Kaye-Stansel Connection for Systemic Outflow Tract Obstruction After Fontan Operation.

Late systemic outflow tract obstruction following completion of the Fontan palliation is rarely seen and is a difficult problem to treat. Absence of the main pulmonary trunk and pulmonary valve at this stage makes a conventional Damus-Kaye-Stansel connection difficult to achieve. We report the case of a 37-year-old female who underwent Fontan completion as an adult and subsequently presented with systemic outflow tract obstruction. A valved conduit was interposed between the native pulmonary annulus and the ascending aorta to create a modified Damus-Kaye-Stansel type connection.

Cryopreserved valved femoral vein homografts for right ventricular outflow tract reconstruction in infants.

Background: We have previously reported use of cryopreserved valve femoral vein homograft (FVH) conduits for biventricular repairs in infants needing right ventricular outflow tract (RVOT) reconstruction. This study aims to compare FVH conduits with aortic (A) and pulmonary (P) homografts with regards to intermediate- and long-term outcomes. Methods: Retrospective review was conducted of all infants between 2004 and 2016 who underwent biventricular repair with RVOT reconstruction using homograft conduits. Patients were divided into A, P, and FVH groups based upon type of conduit received (N = 57 [A = 13; P = 21, FVH = 23]). Groups were compared using univariate and multivariable Cox regression analyses. The Nelson-Aalen estimator of cumulative hazard and Kaplan-Meier curves were used to identify differences in freedom from catheter reintervention and reoperation. Results: The 2 groups were comparable except for greater incidence of delayed sternal closure and longer hospital length of stay in the FVH group. The follow-up was longer for A and P groups compared with the FVH group (P < .001). Multivariable Cox regression, adjusting for difference in the length of follow-up, revealed comparable freedom from overall reintervention between the groups. Younger age at implantation was the only independent predictor of overall reintervention (hazard ratio per day younger age, 1.06; 95% confidence interval, 1.02-1.11; P = .002). Nelson-Aalen cumulative hazard analysis revealed greater freedom from percutaneous reintervention with use of FVH. Kaplan-Meier analysis showed comparable freedom from reoperation for all three conduits. Conclusions: Valved femoral vein homograft conduits are comparable with aortic and pulmonary homografts for RVOT reconstruction in infants undergoing biventricular repairs.

Complete unroofing of the intramural coronary artery for anomalous aortic origin of a coronary artery: The role of commissural resuspension?

OBJECTIVES: Although surgical repair of an anomalous aortic origin of the coronary artery has low operative mortality, longer-term risk of ischemia and aortic regurgitation remains concerning. We routinely perform aortic commissure resuspension after unroofing and sought to evaluate the outcomes with regard to aortic valve competence, symptoms, and signs of ischemia with this approach. METHODS: Twenty-six consecutive patients who received the unroofing procedure for anomalous aortic origin of the coronary artery (10 left; 16 right) between 2004 and 2016 were reviewed. In addition to complete unroofing of the intramural coronary, patients early in the cohort (n = 9) received unroofing only, and aortic commissural resuspension was performed routinely in the subsequent patients (n = 17). Outcomes between commissural resuspension versus no commissural resuspension were compared. The occurrence of mild and greater aortic regurgitation was assessed using a time-to-event analysis after varying lengths of time. Commissural resuspension was considered as the predictor, and the groups were compared using a log-rank test. RESULTS: There was no operative mortality. One patient in the no commissural resuspension group died 10 years later of prosthetic aortic valve endocarditis (aortic valve replacement 7 years after unroofing). The follow-up duration was 6.9 years (4.9-9.1) and 3.7 years (2.1-4.3) in the no commissural resuspension and commissural resuspension groups, respectively (P = .001). Available postoperative exercise stress test data (n = 14) revealed that 50% had an endurance level at the 25th percentile or greater for age. After a median follow-up of 1.9 years (3 months to 10.6 years), no patient in the commissural resuspension group had aortic regurgitation, whereas 6 of 9 patients (67%) in the no commissural resuspension group had stable but mild or greater aortic regurgitation. Time-to-event analysis with the primary event of occurrence of mild or greater aortic regurgitation showed significantly higher freedom from the occurrence of aortic regurgitation in the commissural resuspension group (P = .035). CONCLUSIONS: Surgical repair of an anomalous aortic origin of the coronary artery can be performed with excellent early and midterm outcomes. Routine commissural resuspension of the aortic valve may lead to a lower rate of aortic valve regurgitation without increasing the risk of ischemia.

Unusual Intramural Coronary Artery With Vertical Course Complicating an Arterial Switch Operation.

Intramural coronary arteries in patients with d-transposition of the great arteries (d-TGA) usually arise from the opposite sinus of Valsalva and traverse horizontally across the posterior/facing commissure before emerging externally from the appropriate sinus of Valsalva. Failure to make appropriate technical modifications during coronary transfer can result in an important risk of posttransfer ischemia. We report a case with an unusual course of an intramural left anterior descending (LAD) coronary artery in a patient with d-TGA, with origin at the mid ascending aorta and a vertical intramural course, increasing the susceptibility to injury during an arterial switch operation (ASO).

Intra-Extracardiac Versus Extracardiac Fontan Modifications: Comparison of Early Outcomes.

BACKGROUND: The intra-extracardiac (IE) Fontan modification has advantages over the lateral tunnel modification. A direct comparison of IE to the extracardiac (EC) modification so far has not been done. This study compared IE to EC Fontan with respect to early postoperative outcomes. METHODS: We retrospectively compared outcomes of the Fontan operation using the IE or EC conduit modification between January 2012 and December 2016. IE and EC groups were compared using univariate and multivariable regression analysis. To eliminate the confounding effects of fenestration, repeat intergroup comparison was performed after excluding nonfenestrated patients. RESULTS: There were 81 patients grouped according to Fontan modification into the IE group (n = 43) or EC group (n = 38). The Fontan was fenestrated in 100% of the IE group but in only 55% of the EC group (p < 0.001). Cardiopulmonary bypass time was shorter for the IE group (74 vs 103, p < 0.001) The IE patients had median cross-clamp time of 34 minutes, whereas only 2 patients in the EC group required cross-clamping (35 and 95 minutes; p < 0.001). The IE group had significantly shorter median duration of pleural effusion (8 days vs 11 days, p = 0.007) and hospital length of stay (9 days vs 13 days, p = 0.001) than the EC group. Multivariable linear regression analysis revealed that the IE modification was independently associated with reduced duration of pleural effusion (p = 0.004) and hospital length of stay (p = 0.003). Presence of any unfavorable hemodynamics on preoperative assessment was also associated with longer duration of pleural effusion and hospital length of stay for patients with fenestration. CONCLUSIONS: The IE Fontan modification may be associated with reduced duration of postoperative pleural effusion and hospital length of stay compared with the EC modification.