Patient characteristics for the whole cohort, and for patients with surgery versus patients without surgery during the follow-up
| All patients (n=79) | Patients with surgery* (n=31) | Patients without surgery (n=48) | p Value† | |
| Clinical status | ||||
| Age at CMR, years | 37.1±15.1 | 35.1±15.5 | 38.3±15.0 | 0.361 |
| Male gender, n (%) | 36 (46) | 13 (42) | 23 (48) | 0.602 |
| Body surface area, m2 | 1.68±0.12 | 1.68±0.12 | 1.69±0.12 | 0.630 |
| NYHA functional class 1/2/3, n (%) | 30 (38)/39 (49)/10 (13) | 4 (13)/24 (77)/3 (10) | 26 (54)/15 (31)/7 (15) | <0.001 |
| Atrial septal defect/patent foramen ovale, n (%) | 25 (32)/24 (30) | 15 (48)/12 (39) | 10 (21)/12 (25) | <0.001 |
| Sinus rhythm, n (%)‡ | 73 (92) | 29 (94) | 40 (83) | 0.363 |
| QRS duration, ms | 130.4±26.1 | 140.9±24.5 | 120.5±24.0 | 0.002 |
| QRS fractionation, n (%) | 32 (49) | 23 (72) | 9 (27) | <0.001 |
| Accessory pathway, n (%) | 12 (15) | 4 (13) | 8 (17) | 0.649 |
| Oxygen saturations at rest in room air (%) | 97 (96–98) | 96 (94–98) | 98 (96–98) | 0.023 |
| Previously documented arrhythmia, n (%) | 19 (24) | 7 (23) | 12 (25) | 0.806 |
| AVRT (WPW)/AT/paroxysmal AF, n (%) | 11 (14)/5 (6)/3 (4) | 3 (10)/4 (13)/0 (0) | 8 (17)/1 (2)/3 (6) | – |
| LV non-compaction, n (%)§ | 15 (19) | 12 (39) | 3 (6) | 0.090 |
| Cardiothoracic ratio (n=71) | 0.57±0.08 | 0.58±0.04 | 0.56±0.09 | 0.463 |
| Brain natriuretic peptide, pmol/L (n=50) | 10.5 (5.8–20.8) | 15.0 (8.0–27.0) | 7.0 (5.0–15.0) | 0.017 |
| Peak VO2, mL/kg/min (n=50) | 22.0±7.5 | 19.5±6.0 | 24.0±8.0 | 0.032 |
| Peak VO2% (n=50) | 67.3±22.1 | 58.7±17.2 | 74.0±23.5 | 0.014 |
| CMR | ||||
| Qp:Qs | 1.0±0.2 | 1.0±0.2 | 1.1±0.3 | 0.579 |
| Cardiac index (L/min/m2) | 3.3±1.3 | 2.9±0.9 | 3.6±1.5 | 0.021 |
| Functional RA volume index, mL/m2 | 147.5 (104.7–214.5) | 211.8 (173.7–246.3) | 123.1 (98.8–160.0) | 0.001 |
| Native RA volume index, mL/m2 | 112.5 (83.6–172.6) | 160.3 (114.7–185.1) | 100.5 (81.1–133.3) | <0.001 |
| Atrialised RV volume index, mL/m2 | 40.7 (25.8–69.3) | 63.0 (45.4–92.5) | 33.5 (25.1–53.1) | 0.001 |
| Tricuspid regurgitant fraction, % | 33.7 (24–56) | 51.8 (30–61) | 26.3 (23–36) | 0.004 |
| Apical septal leaflet displacement, mm | 46.6±15.4 | 53.0±17.3 | 42.9±12.8 | 0.004 |
| Apical septal leaflet displacement indexed, % | 53.5±18.6 | 60.0±19.9 | 49.4±16.8 | 0.013 |
| Functional RV end diastolic volume index, mL/m2 | 120.2 (92.5–162.7) | 152.9 (120.0–189.1) | 108.7 (86.0–126.7) | <0.001 |
| Functional RV end systolic volume index, mL/m2 | 63.9 (46.2–87.5) | 86.9 (65.0–105.1) | 51.6 (41.1–66.3) | <0.001 |
| Functional RV stroke volume index, mL/m2 | 57.4 (46.0–78.0) | 74.2 (55.6–85.3) | 50.2 (41.9–65.9) | <0.001 |
| Functional RV ejection fraction, % | 46.5±7.1 | 45.0±5.7 | 47.4±7.8 | 0.144 |
| Functional RV/LV end diastolic indexed volume ratio | 1.58 (1.21–2.32) | 2.32 (1.72–2.90) | 1.34 (1.06–1.71) | <0.001 |
| LV end diastolic volume index, mL/m2 | 81.8 (67.5–93.6) | 72.8 (65.2–83.7) | 85.7 (73.9–101.9) | 0.004 |
| LV end systolic volume index, mL/m2 | 38.1 (31.3–45.5) | 35.4 (26.5–43.3) | 39.9 (31.8–48.4) | 0.117 |
| LV stroke volume index, mL/m2 | 41.2 (35.2–50.9) | 38.8 (32.9–46.9) | 44.5 (36.2–53.9) | 0.014 |
| LV ejection fraction, % | 53.6±7.4 | 52.2±6.2 | 54.5±8.0 | 0.392 |
| Total R/L volume index | 2.7 (1.9–4.4) | 4.4 (2.9–6.0) | 2.1 (1.8–3.2) | <0.001 |
| Severity index | 0.70 (0.46–0.92) | 0.89 (0.70–1.01) | 0.62 (0.42–0.83) | 0.010 |
*Tricuspid valve replacement (bioprosthesis/mechanic n=20/1), tricuspid valve repair (n=11), RV/RA plication (n=20/16), Patent Foramen Ovale(PFO)/Atrial Septal Defect (ASD) closure (n=10/12), ASD enlargement (n=1), MACE/cryoablation (n=5/13). Selection for surgery was based on clinical symptoms including exercise intolerance.
†Mann-Whitney/t-test/χ2.
‡ Sinus rhythm in 73 and established AF in 6.
§ Non-compacted to compacted myocardium (NC/C) ratio >2.3.
AF, atrial fibrillation; AT, atrial tachycardia; AVRT, atrioventricular re-entry tachycardia; CMR, cardiovascular magnetic resonance; LV, left ventricular; MACE, major adverse cardiovascular event; NYHA, New York Heart Association; Qp:Qs, ratio of pulmonary to aortic flow; RA, right atrium; RV, right ventricular; WPW, Wolff-Parkinson-White syndrome
Statistically significant p values are displayed in bold format.