Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect. Postoperative patients with TOF are mostly compromised by chronic pulmonary regurgitation and chronic right ventricular volume load. These patients suffer from impaired exercise capacity and have an increased risk of sudden cardiac death (SCD) and heart failure. This thesis investigates the long-term outcome of surgically corrected TOF patients in a population-based setting. It also assesses the effects of long-lasting pulmonary regurgitation (PR) in the postoperative state in children and adolescents with TOF and healthy control subjects. During the period from 1962 to 2007 a total of 600 patients with TOF were surgically corrected in Finland before the age of 15 years. The follow-up time of these patients was 23±12.1 years. We observed that: i. 514 (85%) patients were alive and living in Finland; 82 (14%) had died. Primary repair of TOF was found to predict lower mortality and longer event-free survival when compared with two-stage repair. The need for a transannular patch (TAP) in TOF surgery carried a higher risk of re-operation without impact on late survival. In addition to the population-based follow-up study, we conducted a single centre cross-sectional study including 45 patients after repair of tetralogy of Fallot (rTOF) and 45 healthy age- and gender-matched paediatric and adolescent volunteers as controls (CO). Cardiac magnetic resonance (CMR) imaging was performed on all the study subjects. We made the following observations: ii. Late gadolinium enhancement (LGE), detected with CMR after gadolinium contrast agent, was also found outside the surgically affected areas in the right ventricle (RV) of TOF patients. Severity of PR correlated with the degree of LGE. LGE is recognized as a marker of fibrosis, scars, or otherwise abnormal myocardium. iii. In children and adolescents with TOF, severe pulmonary regurgitation importantly affects volume flow through the left atrium. Reduction in left ventricular (LV) preload volume may be an additional factor contributing to LV dysfunction. iv. RV longitudinal strain is increased in paediatric TOF patients with severe pulmonary regurgitation. In comparison with healthy volunteers, all TOF patients demonstrated enhanced and delayed RV circumferential strain that was accentuated in the apical region. In conclusion, the late results of TOF surgery are excellent. Patients operated on in the last two decades can expect to have a life expectancy comparable to their healthy peers. Early primary correction and avoidance of TAP if possible are predictors of superior late outcome. Chronic pulmonary regurgitation has deleterious effects on both right and LV filling and function. Novel methods such as LGE analysis, feature tracking (FT), and evaluation of LV preload may prove valuable when assessing the need for pulmonary valve replacement (PVR).
|Status||Publicerad - 2019|
|MoE-publikationstyp||G5 Doktorsavhandling (artikel)|
Bibliografisk informationM1 - 92 s. + liitteet
- 3123 Kvinno- och barnsjukdomar
- 3126 Kirurgi, anestesiologi, intensivvård, radiologi