Table 2.
Changes in cardiovascular function by cardiac magnetic resonance imaging and exercise capacity over time
| Initial test | Follow up | Difference | P-value | |||
|---|---|---|---|---|---|---|
| Magnetic resonance imaging (n = 65) | ||||||
| Age at magnetic resonance imaging (years) | 11.9 (2.8) | 16.4 (3.6) | 4.5 (1.8) | |||
| Pulmonary valve regurgitant fraction (%) | 37 (16) | 35 (14) | −1.7 (8.5) | 0.13 | ||
| Indexed right ventricular end diastolic volume (ml/m2) | 120 (34) | 128 (34) | 9 (24) | 0.006 | ||
| Indexed right ventricular end systolic volume (ml/m2) | 49 (20) | 56 (23) | 8 (17) | 0.001 | ||
| Right ventricular ejection fraction (%) | 59.9 (7.7) | 56.3 (7.8) | −3.6 (8.0) | 0.001 | ||
| Total right ventricular stroke volume (ml) | 89.1 (±31) | 111 (±31) | +21.9 (±26.4) | <0.001 | ||
| Indexed effective right ventricular stroke volume (ml/m2) | 41.1 (34.3–48) | 42.6 (35.1–49.4) | 0.19 | |||
| Right ventricular cardiac index (L/min/m2) | 5.6 (1.5) | 5.7 (1.4) | 0.1 (1.3) | 0.65 | ||
| Indexed left ventricular end diastolic volume (ml/m2) | 65.2 (12.7) | 63.4 (11.3) | −1.4 (11.7) | 0.37 | ||
| Indexed left ventricular end systolic volume (ml/m2) | 20.6 (6.4) | 20.1 (5.7) | 0.34 (6) | 0.68 | ||
| Left ventricular ejection fraction (%) | 68.8 (6.6) | 68.2 (6.2) | −0.6 (6.3) | 0.45 | ||
| Indexed left ventricular stroke volume (ml/m2) | 20.6 (6.3) | 20.1 (5.7) | −0.34 (0.82) | 0.68 | ||
| Left ventricular cardiac index (L/min/m2) | 3.5 (0.7) | 3.5 (0.7) | −0.05 (0.7) | 0.59 | ||
| Exercise stress test (n = 63) | ||||||
| Age at exercise stress test (years) | 11.2 (2.5) | 15.2 (2.9) | 4 (1.6) | |||
| Minute oxygen consumption at peak exercise (% of predicted) | 78 (17) | 82 (19) | 4 (18) | 0.10 | ||
| Minute oxygen consumption at anaerobic threshold (% of predicted) | 86 (19) | 90 (19) | 4 (18) | 0.32 | ||
| Forced vital capacity (% of predicted) | 80 (12) | 87 (15) | 7 (10) | <0.0001 | ||
| Maximal work rate (% of predicted) | 87 (23) | 82 (22) | −5 (18) | 0.063 | ||
| O2 pulse (ml/kg*min) | 6.6 (2.3) | 11. (3.3) | 4.4 (0.42) | <0.0001 | ||
| Indexed O2 pulse (ml/kg/min/m2) | 5 (1.5) | 6.7 (1.9) | 1.7 (0.62) | 0.17 | ||
| Maximum heart rate | 179 (16) | 179 (15) | 0 (14) | 0.77 | ||
| Maximal work rate (n/%)% | 30 (51) | 51 (86) | <0.0001 | |||
| Electrocardiograms (n = 95) | ||||||
| QRS duration | 130 (110; 140) | 144 (118; 158) | 10 (4;20) | <0.0001 | ||
| Sinus rhythm | 81 (90%) | 82 (86%) | 0.40 | |||
Values are mean (± standard deviation), percentage, or count (%) where appropriate.
Maximal work rate (n/%)/% indicates the number of subjects that achieved normal work rate.