Comparison of late results of arterial switch versus atrial switch (mustard procedure) operation for transposition of the great arteries

Right Ventricular Systolic Dysfunction in Adults With Anatomic Repair of d-Transposition of Great Arteries

The purpose of this study was to assess the prevalence of right ventricular (RV) systolic dysfunction in adults with anatomic repair of dextro-transposition of great arteries (d-TGAs), and to determine its relation to clinical outcomes across multiple domains (functional status, peak oxygen consumption, N-terminal pro-brain natriuretic peptide, and heart failure hospitalization). Adults with anatomic repair for d-TGA and with echocardiographic images for strain analysis were divided into 2 groups: (1) d-TGA status after an arterial switch operation (d-TGA-ASO group) and (2) d-TGA status after a Rastelli operation (d-TGA-Rastelli group). RV systolic function was assessed using RV global longitudinal strain (RVGLS), and RV systolic dysfunction was defined as RVGLS >-18%. We identified 151 patients (median age 21 years [19 to 28]; d-TGA-ASO group 89 [59%], and d-TGA-Rastelli group 62 [41%]). The mean RVGLS was -22 ± 4%, and 47 patients (31%) had RV systolic dysfunction. The d-TGA-Rastelli group had lower (less negative) RVGLS than that of the d-TGA-ASO group (-19 ± 3% vs -25 ± 3%, p <0.001) and higher prevalence of RV systolic dysfunction (48% vs 19%, p <0.001). RVGLS (absolute value) was associated with peak oxygen consumption (r = 0.58, p <0.001; adjusted R2 = 0.28), log-N-terminal pro-brain natriuretic peptide (r = -0.41, p = 0.004; adjusted R2 = 0.21), New York Heart Association class III/IV (odds ratio 2.29, 1.56 to 3.19, p = 0.01), and heart failure hospitalization (hazard ratio 0.93, 0.88 to 0.98, p = 0.009). RV systolic dysfunction was common in adults with d-TGA and anatomic repair and was associated with clinical outcomes. Longitudinal studies are required to determine the risk factors for progressive RV systolic dysfunction and to identify strategies for preventing RV systolic dysfunction in this population.

Right and Left Ventricular Strain Patterns After the Atrial Switch Operation for D-Transposition of the Great Arteries-A Magnetic Resonance Feature Tracking Study

Introduction: Adult survivors of the atrial switch operation for transposition of the great arteries present with a systemic morphologic right ventricle and a subpulmonary morphologic left ventricle. This physiology can be considered a model for the effects of long-term right ventricular pressure overload and of decreased left ventricular afterload. We aimed to determine the impact of these chronically altered loading conditions on myocardial deformation of the ventricles.

Materials and methods: Two-dimensional steady state free precession cine images of 29 patients after atrial repair (age 29 ± 7 years) and 19 controls (24 ± 10 years; n.s.) were post-processed with feature tracking software (TomTec 2D CPA). Volumes, ejection fractions, global and free wall longitudinal and circumferential strains of both ventricles were compared between both groups.

Results: Systemic right ventricular global longitudinal strain was decreased in patients compared to controls (−12.9 ± 3.3% vs. −18.9 ± 4.6%, p < 0.001), while right ventricular circumferential strain was unchanged (−15.8 ± 3.4% vs. −15.1 ± 5%; n.s.). Left ventricular longitudinal strain was similar in both groups (−17 ± 5.6% vs. −17.5 ± 4.6%; n.s.), but global left ventricular circumferential strain was lower in patients (−20.7 ± 4.1% vs. −27.3 ± 4.5%, p < 0.001). The systemic right ventricle, compared to the systemic left ventricle, showed decreased global longitudinal (p < 0.001) and circumferential strain (p < 0.001). The subpulmonary left ventricle, compared to the subpulmonary right ventricle, demonstrated similar longitudinal (p = 0.223) but higher circumferential strain (p < 0.001).

Conclusions: In patients after atrial switch repair for transposition of the great arteries, the systemic right ventricle shows poor longitudinal strain, but maintains normal right ventricular circumferential strain. The left ventricle shows higher circumferential strain than the right ventricle, in both systemic and subpulmonary positions.

Left ventricular function and exercise capacity after arterial switch operation for transposition of the great arteries: a systematic review and meta-analysis

BACKGROUND

The arterial switch operation for transposition of the great arteries was initially believed to be an anatomical correction. Recent evidence shows reduced exercise capacity and left ventricular function in varying degrees in the long term after an arterial switch operation.

OBJECTIVE

To perform a meta-analysis on long-term exercise capacity and left ventricular ejection fraction after an arterial switch operation.

METHODS

A literature search was performed to cover all studies on patients who had undergone a minimum of 6 years of follow-up that reported either left ventricular ejection fraction, peak oxygen uptake, peak workload, and/or peak heart rate. A meta-analysis was performed if more than three studies reported the outcome of interest.

RESULTS

A total of 21 studies reported on the outcomes of interest. Oxygen uptake was consistently lower in patients who had undergone an arterial switch operation compared with healthy controls, with a pooled average peak oxygen uptake of 87.5±2.9% of predicted. The peak heart rate was also lower compared with that of controls, at 92±2% of predicted. Peak workload was significantly reduced in two studies. Pooled left ventricular ejection fraction was normal at 60.7±7.2%.

CONCLUSION

Exercise capacity is reduced and left ventricular ejection fraction is preserved in the long term after an arterial switch operation for transposition of the great arteries.

Large Calibre Self-Expanding Stents for Pulmonary Stenosis After the Arterial Switch, a Low-Risk Solution to a Low-Flow Situation

Branch pulmonary artery stenosis is one of the most common complications late after the arterial switch operation. The pathophysiology of stenosis in these circumstances is very different to that encountered in with normally related great vessels. The LeCompte manoeuvre leaves the pulmonary arteries straddled and stretched over the aortic root which contributing significantly to the degree of stenosis encountered. Unilateral branch pulmonary artery stenosis rarely leads to significant symptoms in young patients with biventricular repairs; however, significant discrepancies in the split flows between right and left lung may place the patient in an unfavourable physiological position as they move in to middle age. Balloon expandable stent implantation distorts the anatomical arrangement of the LeCompte and is associated with negative interactions with the often dilated aortic root. We present three cases of the use of flexible self-expanding stents to improve the physiological flow distributions to each lung whilst hopefully decreasing the risk of erosion and perforation or fistula formation related to the pulmonary artery. All three patients had uncomplicated procedures with significant improvements in vessel diameter and flow distribution noted on follow-up MRI scans. This is the first report of the use of self-expanding stents in the context of branch pulmonary artery stenosis after the LeCompte manoeuvre. Theoretically and based on our early experience, this technique provides potential safety advantages over the use of more traditional balloon expandable stents.

Stress Echocardiographic Evaluation for D-Transposition of the Great Arteries after Atrial Redirection: Unmasking Early Signs of Myocardial Dysfunction and Baffle Stenosis

BACKGROUND

The authors used semisupine cycle ergometry stress echocardiography to assess cardiac function and unmask baffle stenosis in patients with d-transposition of the great arteries after atrial redirection surgery.

METHODS

This was a retrospective review of semisupine cycle ergometry stress echocardiography performed in 53 patients (64% male; mean age, 24.0 years; 90% Mustard procedure) and 56 healthy control subjects. Incremental exercise to volitional fatigue was performed. Hemodynamic data, echocardiographic cardiac dimensions, area change, tissue Doppler velocities, strain, ventricular synchronization, and superior vena cava flow velocities before and immediately after exercise are reported.

RESULTS

Patients had lower exercise capacity (870 vs 1,854 J/kg, P < .001) and peak heart rates (132 vs 167 beats/min, P < .001). Stroke volume index did not increase with exercise (45 vs 47 mL/m², P = .400). Cardiac index increased in both groups with exercise (3.0 vs 6.1 and 2.9 vs 7.0 L/min/m², P < .001) and was higher in control subjects (P = .006). Right ventricular diastolic and systolic areas decreased significantly with exercise in both the short-axis and four-chamber views. Right and left ventricular contraction time shortened with exercise (405 vs 247 and 338 vs 217 msec, P < .001) and remained synchronous (ratio of right ventricular to left ventricular contraction time = 0.080). Doppler velocities in patients with baffle obstruction were higher in the lower superior vena cava with exercise compared with nonobstructed patients (1.87 vs 1.46 m/sec, P = .020) and normalized after catheter intervention (1.49 vs 1.46 m/sec, P = .800).

CONCLUSIONS

Patients with d-transposition of the great arteries have lower exercise capacity and peak heart rates. The systemic right ventricle presents a lesser but qualitatively normal systolic response and decreased diastolic filling. Semisupine cycle ergometry stress echocardiography unmasked SVC obstruction.

Long-Term Outcome of Mustard/Senning Correction for Transposition of the Great Arteries in Sweden and Denmark

Background—

The atrial switch operation, the Mustard or Senning operation, for the transposition of the great arteries (TGA) was introduced in the late 1950s and was the preferred surgery for TGA until the early 1990s. The Mustard and Senning operation involves extensive surgery in the atria and leaves the right ventricle as the systemic ventricle. The Mustard and Senning cohort is now well into adulthood and we begin to see the long-term outcome.

Methods and Results—

All the 6 surgical centers that performed Mustard and Senning operations in Sweden and Denmark identified all operated TGA patients. Information about death was obtained in late 2007 and early 2008 from the Danish and Swedish Centralised Civil Register by using the patients’ unique national Civil Registration Numbers. Four hundred sixty-eight patients undergoing the atrial switch operation were identified. Perioperative 30-day mortality was 20%, and 60% were alive after 30 years of follow-up. Perioperative mortality was significantly increased by the presence of a ventricular septal defect, left ventricular outflow obstruction, surgery early in the Mustard and Senning era. However, only pacemaker implantation is predictive of long-term outcome (hazard ratio, 1.90; 95% confidence interval, 1.05–3.46, P =0.04), once the TGA patient has survived the perioperative period. The risk of reoperation was correlated to the presence of associated defects and where the first Mustard/Senning operation was performed.

Conclusions—

The long-term survival of patients with Mustard and Senning correction for TGA appears to be primarily determined by factors in the right ventricle and tricuspid valve and not the timing of or the type of surgery in childhood. Cardiac function necessitating the implantation of a pacemaker is associated with an increase in mortality.

Anesthetic Considerations and Management of Transposition of the Great Arteries

Transposition of the great arteries was once an almost uniformly fatal disease in infancy. Six decades of advances in surgical techniques, intraoperative care, and perioperative management have led to at least 90% of patients reaching adulthood, most with a good quality of life. This review summarizes medical and surgical decision making during the neonatal perioperative period, with a special emphasis on factors pertinent to the anesthetic evaluation and care during primary surgical repair of transposition of the great arteries. A review is also provided of anesthetic considerations for noncardiac surgery later in childhood or adulthood, for those survivors of the arterial switch operation, Rastelli procedure, Nikaidoh procedure, and the réparation á l’étage ventriculaire procedure.

Managing heart failure in adults with congenital heart disease

OPINION STATEMENT

The current era of cardiology has seen a significant increase in the number of adults living with congenital heart disease (CHD). Although advances in medical and surgical management have resulted in approximately 90 % of children with CHD living into adulthood, many suffer from late complications, with myocardial dysfunction as the leading cause of morbidity and mortality. The heterogeneity of the adult congenital heart disease (ACHD) population has presented a challenge, as there are only limited data regarding appropriate treatment modalities. Given the growing ACHD population and the high morbidity and mortality related to myocardial dysfunction, a comprehensive approach to heart failure (HF) care is recommended in conjunction with ACHD and HF specialty care. The field must focus on developing research strategies to leverage existing and future medical and surgical treatment options in order to improve outcomes in this diverse population.