Porcine Versus Pericardial Pulmonary Valve Replacement in Adults With Prior Congenital Cardiac Surgery: Midterm Outcomes

Background:

Postcongenital heart surgery pulmonary regurgitation requires subsequent pulmonary valve replacement. We sought to compare the outcomes of pulmonary valve replacement after using bioprosthetic valves, porcine versus pericardial bioprosthesis.

Method:

Retrospective single-center study of consecutive pulmonary valve replacement in patients with pulmonary regurgitation following initial congenital cardiac surgery. From 2004 to 2016, 82 adult patients (53 males, 29 females) underwent pulmonary valve replacement at a mean age of 28.7 ± 8 years (range 18-52 years) with a mean time to pulmonary valve replacement of 24 ± 7 years (range 13-43 years). Porcine bioprosthetic valves (group 1, n = 32) and pericardial valves (group 2, n = 50) were used. Cardiac magnetic resonance imaging was performed (n = 54) at a mean of 18 ± 13 months before and 24 ± 21 months after pulmonary valve replacement.

Results:

No significant difference was seen between the groups except that the mean follow-up was longer for group 1 (5.02 ± 2.06 vs 4.08 ± 3.21 years). In-hospital mortality was 1.1%. Follow-up completeness was 100% with no late death. Mean right ventricular end-systolic and end-diastolic volumes reduced significantly in both the groups ( P < .001), whereas right ventricular ejection fraction remained unchanged (group 1, P = .129; group 2, P = .675) . Only the left ventricular end-diastolic volume increased in both the groups, but the increase was significant for group 2 only (group 1, P = .070; group 2, P = .015), whereas the left ventricular end-systolic and ejection fraction remained unchanged in both the groups. There was no reoperation for pulmonary valve replacement. Freedom from intervention was 93.8% (group 1) and 100% (group 2) at eight years after pulmonary valve replacement ( P = .407).

Conclusion:

Midterm outcomes of pulmonary valve replacement in our adult cohort were satisfactory. Both types of bioprosthetic valves performed comparably for eight years and were a good option in adults.

In-vitro and in-vivo evaluation of a novel bioprosthetic pulmonary valve for use in congenital heart surgery

Background

Management of congenital malformations of the pulmonary artery and valve can be challenging. The severity often demands early intervention, which is rarely definitive due to the natural growth and multiple surgeries may be required. An artificial valve made entirely from biodegradable materials that will serve as a bioscaffold for host recellularization would be an attractive solution for these patients. Such valves have been experimentally evaluated with various results. In this study, a simple valve design supported by an absorbable proximal stabilization ring is evaluated both in-vitro and in-vivo.

Methods

From a 6.7 × 5.0 cm sheet of CorMatrix® tissue we created the valve as an inverted tubegraft with three sutured commissures. A non-closed ring of LactoSorb® basally supported the valve. The commissure height was 2 cm. Inserted as an interposition graft the valve was tested in an in-vitro model and an acute porcine model. Right ventricular and pulmonary artery pressures were recorded.

Results

The in-vitro testing indicated a proper opening and closure function of valve at physiological simulated hemodynamic conditions. The in-vivo evaluation showed a peak right ventricular pressure of 38 mmHg and a peak pulmonary artery pressure of 27 mmHg and thereby a peak valve gradient of 11 mmHg. The pulmonary pressure wave demonstrated a dicrotic notch indicating competence of the valve.

Conclusion

This new pulmonary valve made entirely from biodegradable tissue worked in an acute setting and displayed a good hemodynamic profile. The valve gradient observed is equal to or superior of today’s surgical treatment options.

Tetralogy of Fallot in the Current Era

Only few studies have reported long-term outcome of the transatrial-transpulmonary approach in the current era of management of tetralogy of Fallot (ToF). We investigated 15-year outcome of correction via a transatrial-transpulmonary approach in a large cohort of successive patients operated in the 21st century. All infant ToF patients undergoing transatrial-transpulmonary ToF correction between 2000 and 2015 were included (N = 177, 106 male, median follow-up 7.1 (interquartile range 3.0-10.9) years. Data regarding postoperative complications, reinterventions, development of atrial and ventricular arrhythmia, cardiac function, and survival were evaluated. Prior shunting was performed in 10 patients (6%). The transatrial-transpulmonary approach resulted in valve-sparing surgery in 57 patients (32%). Postoperative surgical complications included junctional ectopic tachycardia (N = 12, 7%), pericardial (N = 10, 6%) or pleural effusion (N = 7, 3%), chylothorax (N = 7, 4%), bleeding requiring reoperation (N = 4, 3%), and superficial wound infection (N = 1). Fifty-one patients underwent 68 reinterventions, mainly due to pulmonary restenosis (PS) (N = 57). ToF correction at age <2 months and double outlet or double-chambered right ventricle variants of the ToF spectrum were independent predictors for reintervention. Patients undergoing valve-sparing ToF correction had a significant longer PR-free survival than those with a transannular patch (8.5 [95% confidence interval 6.8-10.3] years vs 1.1 [95% confidence interval 0.8-1.5] years; P < 0.001). Overall mortality was 2.8%; mortality rates were higher in premature/dysmature newborns (0.7% vs 9.5%; P < 0.001). Although the 15-year outcome of the transatrial-transpulmonary approach in terms of postoperative complications and mortality rates is excellent, the high incidence of moderate and severe PR is worrisome. Valve-sparing surgery was associated with a substantially lower incidence of PR, yet was surgically not possible in the majority of patients.

The value of right ventricular longitudinal strain in the evaluation of adult patients with repaired tetralogy of Fallot: a new tool for a contemporary challenge

OBJECTIVE

The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients.

METHODS

Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method.

RESULTS

In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was -16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=-0.40) and right ventricular ejection fraction (r=-0.45) (all p<0.05), which in turn showed linear correlation with right ventricular fractional area change (r=0.50), pulmonary regurgitation colour length (r=0.35), right ventricular end-systolic volume (r=-0.60), and left ventricular ejection fraction (r=0.36) (all p<0.05). Longitudinal strain (β=-0.72, 95% confidence interval -1.41, -0.15) and left ventricular ejection fraction (β=0.39, 95% confidence interval 0.11, 0.67) were independently associated with right ventricular ejection fraction. The best threshold of longitudinal strain for predicting a right ventricular ejection fraction of <40% was -17.0%.

CONCLUSIONS

Right ventricular longitudinal strain is a powerful method for evaluating patients with tetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.

Percutaneous management of failed bioprosthetic pulmonary valves in patients with congenital heart defects

AIMS

We reviewed our center experience in the field of transcatheter pulmonary valve-in-valve implantation (TPViV), that is emerging as a treatment option for patients with pulmonary bioprosthetic valve (BPV) dysfunction.

METHODS

Between April 2008 and September 2015, a total of six patients with congenital heart disease (four men) underwent TPViV due to stenosis of preexisting BPV. Four patients received a Melody Medtronic Transcatheter Pulmonary Valve and two an Edward Sapien Valve.

RESULTS

No procedural-related complications occurred. After valve implantation, right ventricular systolic pressure (RVSP, 80.5 ± 25.3-41.2 ± 8.35 mmHg, P < 0.05), right ventricular outflow tract (RVOT) gradient (55.3 ± 23.4-10.6 ± 3.8 mmHg, P < 0.05), and RVSP-to-aortic pressure (0.75 ± 0.21-0.38 ± 0.21, P = 0.01) fell significantly. Echocardiograms at follow-up revealed a significant reduction in estimated RVSP (88.7 ± 22-21.7 ± 4.7 mmHg, P < 0.05), in RVOT (76.2 ± 17.9-25.7 ± 6.1 mmHg, P = 0.005), and in mean RVOT (40.7 ± 9.9-15.5 ± 4.8 mmHg, P < 0.05) gradients. Cardiac magnetic resonance showed no significant change in biventricular dimensions and function. Symptomatic patients reported improvement of symptoms, although cardiopulmonary exercise did not show any significant differences.

CONCLUSION

TPViV is an effective and well tolerated treatment for BPV dysfunction, improving freedom from surgical reintervention. Long-term studies will redefine the management of dysfunctional RVOT, either native or surrogate.

The unnatural history of pulmonary stenosis up to 40 years after surgical repair

OBJECTIVE

To provide prospective information on long-term outcome after surgical correction of valvular pulmonary stenosis (PS).

METHODS

Fifty-three consecutive patients operated for PS during childhood between 1968 and 1980 in one centre are followed longitudinally for 37±3.4 years, including extensive in-hospital examination every 10 years.

RESULTS

Survival information was available in 100% of the original 53 patients. Cumulative survival was 94% at 20 years and 91% at 40 years. Excluding perioperative mortality (<30 days), survival was 94% at 40 years. Of 46 eligible survivors, 29 participated in the in-hospital examination and 15 gave permission to use their hospital records (96% participation). Cumulative event-free survival was 68% after 40 years: 25% needed a reintervention, 12% underwent pacemaker implantation and 9% had supraventricular arrhythmias. Early reinterventions were mainly for residual PS, late reinterventions for pulmonary regurgitation. Subjective health status was good. Exercise capacity was normal in 74% (median 96 (82-107)% of expected workload). Right ventricular and left ventricular (LV) dysfunction was found in 13% and 41%, respectively. The use of a transannular patch and younger age at surgery were predictive for late events (HR 3.02 (95% CI 1.09 to 8.37) and HR 0.81/year (95% CI 0.66 to 0.98), respectively). Use of inflow occlusion compared with cardiopulmonary bypass showed a trend towards more reinterventions (HR 3.19 (95% CI 0.97 to 10.47)).

CONCLUSIONS

Survival up to 40 years after successful PS repair is nearly normal. Subjective health status is good and there is a low incidence of arrhythmias. Reinterventions, however, are necessary in one-quarter and 40 years postoperatively several patients show LV dysfunction.

Repaired tetralogy of Fallot with coexisting unrepaired partial anomalous pulmonary venous connection is associated with diminished right ventricular ejection fraction and more severe right ventricular dilation

BACKGROUND

There is an established association between tetralogy of Fallot and partial anomalous pulmonary venous connections. This association is important because surgically repaired tetralogy patients have increased risk of right heart failure. We hypothesize that partial anomalous venous connections increase right ventricular volumes and worsen right ventricular failure.

MATERIALS AND METHODS

We reviewed cardiac MRI exams performed at a tertiary pediatric hospital from January 2005 to January 2014. We identified patients with repaired tetralogy and unrepaired partial anomalous pulmonary venous connection. We used age- and gender-matched repaired tetralogy patients without partial anomalous pulmonary venous connection as controls. We analyzed the MRI results and surgical course and performed comparative statistics to identify group differences.

RESULTS

There were eight patients with repaired tetralogy and unrepaired partial anomalous pulmonary venous connection and 16 controls. In all cases, the partial anomalous pulmonary venous connection was not detected on preoperative echocardiography. There were no significant differences in surgical course and body surface area between the two groups. Repaired tetralogy patients with unrepaired partial anomalous pulmonary venous connection showed significantly higher indexed right ventricular end diastolic volume (149 ± 33 mL/m(2) vs. 118 ± 30 mL/m(2)), right ventricle to left ventricle size ratios (3.1 ± 1.3 vs. 1.9 ± 0.5) and a higher incidence of reduced right ventricular ejection fraction compared to controls (3/8 vs. 0/16).

CONCLUSION

Repaired tetralogy of Fallot with unrepaired partial anomalous pulmonary venous connection is associated with reduced right ventricular ejection fraction and more significant right ventricular dilation.

Echocardiographic assessment after surgical repair of tetralogy of fallot

Surgical correction of tetralogy of Fallot is still one of the most frequently performed intervention in pediatric cardiac surgery, and in many cases, it is far from being a complete and definitive correction. It is rather an excellent palliation that solves the problem of cyanosis, but predisposes the patients to medical and surgical complications during follow-up. The decision-making process regarding the treatment of late sequel is among the most discussed topics in adult congenital cardiology. In post-operative Fallot patients, echocardiography is used as the first method of diagnostic imaging and currently allows both a qualitative observation of the anatomical alterations and a detailed quantification of right ventricular volumes and function, of the right ventricular outflow tract, and of the pulmonary valve and pulmonary arteries. The literature introduced many quantitative echocardiographic criteria useful for the understanding of the pathophysiological mechanisms involving the right ventricle and those have made much more objective any decision-making processes.

Comparison of long-term postoperative sequelae in patients with tetralogy of Fallot versus isolated pulmonic stenosis

Patients with tetralogy of Fallot (TOF) after complete repair and pulmonic stenosis (PS) after surgical valvotomy often develop significant pulmonic regurgitation (PR) that eventually requires valve replacement. Although criteria exist for the timing of pulmonary valve replacement in TOF, it remains less clear when to intervene in valvotomy patients and whether TOF recommendations can be applied. Our aim was to compare the structural and functional sequelae of valvotomy for PS with complete repair for TOF. We compared the clinical characteristics, electrocardiograms, echocardiograms, cardiac magnetic resonance imaging (MRI), and invasive hemodynamics of 109 adults (34 PS and 75 TOF) newly referred to a congenital heart disease center for evaluation of PR between 2005 and 2012. Both cohorts were similar in terms of baseline demographics and presenting New York Heart Association function class. Valvotomy patients had a slightly greater degree of PR by echocardiogram, although it was similar by cardiac MRI. Electrocardiography QRS width was greater in patients with TOF (114±27 vs 150±28 ms, p<0.001). MRI right ventricular ejection fraction (49±8 vs 41±11%, p=0.001) and left ventricular ejection fraction (59±7 vs 52±10%, p=0.002) were lower in patients with TOF. Pacemaker or defibrillator implantation was significantly greater in patients with TOF (3% vs 23%, p=0.011). In conclusion, patients postvalvotomy and complete repair present with similar degrees of PR and severity of symptoms. Biventricular systolic function and electrocardiography QRS width appear less affected, suggesting morphologic changes in TOF and its repair that extend beyond the effects of PR. These findings suggest the need for developing disease-specific guidelines for patients with PR postvalvotomy.