Shivaram P, Padiyath A, Bai S, Gossett JM, Thomas Collins R.
Am J Cardiol. 2018 Dec 1;122(11):1972-1976. doi: 10.1016/j.amjcard.2018.08.044. Epub 2018 Sep 8.
Take Home Points
- This retrospective analysis questioned how often in asymptomatic patients (mostly paediatric) with no change in physical exam, that transthoracic echocardiography (TTE) altered clinical practice.
- Over a 32 year period (1983-2015), a total of 1792 TTEs of 149 patients were reviewed. 93% of TTEs examined were in patients <15 years old.
- The median number of echocardiograms per patient was 12 (range 1-34).
- Only 20 echocardiograms (1.1%) led to an ‘actionable change’ in clinical management i.e. medication change, interventional catheter or surgical procedure.
- The most common intervention was for a cardiac catheter (13 out of 20, 65%) and most actionable changes occurred in a 10 year interval after the arterial switch procedure.
- This retrospective analysis conjects that patients with an arterial switch may be subject to overinvestigation (i.e. echocardiography).
- There is the potential to rationalise and increase the scan interval between TTEs in patients who have undergone a simple arterial switch procedure, particularly in the paediatric age range.
- The number of adult patients in this analysis was small so assessing the utility of TTE surveillance in adult patients who have undergone ASO in childhood requires further investigation.
Commentary from Dr. Damien Cullington (Leeds UK), section editor of ACHD Journal Watch:
Patients with a history of transposition of the great arteries (TGA) who have undergone the arterial switch operation (ASO) comprise a growing body of patients attending for regular ACHD follow up. For about the last 30 years, in most congenital cardiac surgical centres, the ASO has replaced the atrial switch for treatment of TGA- apart from perhaps the most challenging of cases. For the management and planned follow up for many congenital cardiac conditions, generic guidance has been arbitrarily defined and recently updated in the 2018 AHA/ACC guidelines for the management of adults with congenital cardiac disease. For adult patients who are clinically well, it is recommended that TTE interval assessment can be individualised and repeated every 12-24 months.
Shivaram et al. have performed a retrospective analysis of TTEs, mostly in paediatric patients which sought to question what the utility of an annual echo is in patients who have had an ASO – does this result in an ‘actionable change’ (AC)? The clinical characteristics of the population are shown in Table 1. An AC found on TTE was defined by the authors as one which was not secondary to change in symptoms or physical examination but resulted in at least one of four interventions – medication change; hospital admission; cardiac catheter +/- intervention; or surgical intervention.
Over a period of 32 years, only patients with d-TGA who underwent ASO were enrolled. Out of 193 patients identified, 44 were excluded as their study data was inadequate, leaving 149 patients for analysis. An impressive number of TTEs were examined but the majority were performed within a year after surgery (n=931, 53%). Only 51 TTEs (3% of the total) were performed in patients > 20 years old (Table 2).
The results show that in a paediatric age group, most patients following ASO are clinically stable from a TTE perspective. Most ACs (90%) occurred in patients <15 years (Table 3) with a greater tendency for ACs to occur in more complex forms of ASO Table 4.
Utility of TTE surveillance in adult patients undergoing ASO.
The number of patients in the analysis who had reached adulthood was only small – only 33 patients were >15 years old (22% of the cohort) with rapidly diminishing numbers thereafter (Figure 1). This is important to highlight since this study cannot confidently assess the long-term utility of TTE surveillance in comparison to the larger number of patients in the paediatric age range group.
In this analysis there appears to be very low rates of complications requiring re-intervention after childhood ASO. Patients with more complex ASO have a tendency for more complications. It is suggested that for those patients with simple TGA as their original anatomy, scans intervals could potentially be more widely spaced.
Although the authors assert that follow up TTEs ‘are rarely of any clinical utility’, we can’t forget that for some patients and their families, investigations like a TTE, can help to give clinical assurances and some families will view this as a standard component of a thorough clinical evaluation irrespective of the low likelihood of complications occurring. Care should be individualised.
This analysis focusses primarily on a paediatric age group rather than an adult one so extrapolating the available evidence to make recommendations on the utility of TTE surveillance in adults with ASO should be explored further.