21: Karunanithi Z, Andersen MJ, Mellemkjær S, Alstrup M, Waziri F, Skibsted Clemmensen T, Elisabeth Hjortdal V, Hvitfeldt Poulsen S. Elevated Left and Right Atrial Pressures Long-Term After Atrial Septal Defect Correction: An Invasive Exercise Hemodynamic Study. J Am Heart Assoc. 2021 Jul 20;10(14):e020692. doi:10.1161/JAHA.120.020692. Epub 2021 Jul 14. PMID: 34259012; PMCID: PMC8483478.
Take Home Points:
- Patients with corrected ASD have elevated RA and LA pressures at rest and during exercise (either due to intrinsic atrial abnormality and/or alteration of the LV diastolic properties)
- These changes are present despite having a preserved exercise capacity.
- The abnormal atrial compliance and systolic atrial function noted here, may be a contribute to the long term atrial fibrillation risk
Commentary from Dr. Blanche Cupido (Cape Town, South Africa), chief section editor of ACHD Journal Watch:
Patients with ASD, despite correction, have a higher mortality and morbidity rate compared to the general population. Surgical and percutaneous correction aims to reduce RV volumes, RA and LA volumes and RV function. This is a single center study from Denmark assessing the physical activity, cardiac performance and invasive exercise hemodynamics in patients with a corrected ASD – the hypothesis is that despite correction, the hemodynamic effects are lasting and may explain some of the long term complications if ASD like arrythmias and propensity to pulmonary infections.
Patients with an isolated secundum ASD between August 2018 and October 2019 were enrolled. The diagnosis had to have been made by 2 years of age and should be at least 3 years out since their intervention. A total of 38 patients were enrolled (19 surgical correction, 19 percutaneous closure). Nineteen healthy age-matched controls were enrolled. All patients had a right heart catheterization at rest and during exercise with simultaneous expired gas recordings and an echocardiogram. A semi-supine ergometer was used workload increased at 3-minute intervals.
Table 1 shows that the 2 cohorts were similar in terms of demographic criteria. Echocardiography at rest showed no differences in the LV and RV volumes between the 2 groups. Furthermore, the LV systolic function was preserved and similar in both groups. The E/A ration in the ASD group trended higher but this was not statistically significant. Both TAPSE and RV longitudinal strain was reduced in the ASD compared to the control group though still within the limits of normal.
Resting heart rate was higher in the ASD. Group. Peak oxygen uptake was also similar between the 2 groups (35.2±7.5 ml/kg/min in controls and 32.7±7.7 ml/kg/min in ASD group, p=0.3).
Table 3 shows the hemodynamic findings between the 2 groups. At rest, there were no differences between the control group and those with an ASD in terms of mean right atrial pressure (RAP), mean pulmonary wedge pressure or mean pulmonary artery pressure. With exercise, the ASD group had a significant increase in pulmonary pressures, pulmonary wedge pressures and trans-mural filling pressures (the latter 2 parameters perhaps implying abnormal exercise induced LV diastolic properties). Neither time since intervention nor the type of intervention correlated significantly with these findings.
Pulmonary wedge v wave was increased at rest and on exercise in the ASD group implying impaired LA compliance. In the right atrium, the RA a wave increased significantly in the ASD group compared to controls. (Figure 1)
An abnormal exercise response was defined as a mean pulmonary wedge pressure ≥25mmHg and/or mean pulmonary artery pressure ≥35mmHg at peak exercise. All participants in the control group had a normal exercise response. A third of the ASD group had an abnormal exercise response (n=13). These patients demonstrated significantly elevated mean pulmonary wedge pressures and peak a and v wave pressures compared to both the control group and those ASD patients with a normal exercise response. Since LVEDP was not measured directly, one can’t be certain if this represents intrinsic LA abnormalities or impaired LV diastology or a combination of the 2 (Figure 2).
Furthermore, transmural filling pressures are increased at both rest and on peak exercise in this group most likely representing impaired LV compliance.