Severe pulmonary regurgitation in adolescents with tetralogy of Fallot leads to increased longitudinal strain.

OBJECTIVES: Postoperative patients with tetralogy of Fallot (TOF) are often compromised by chronic pulmonary regurgitation and chronic right ventricular volume load. We sought to determine whether pulmonary regurgitation (PR) would affect right and left ventricle (RV and LV) strain. MATERIALS AND METHODS: This cross-sectional analysis included 40 patients who had TOF with surgical repair, with an average follow-up period of 11.8 ± 3.0 years. Altogether, 44 healthy volunteers with similar age and gender distribution were recruited. A cardiovascular magnetic resonance imaging study with feature tracking analysis was performed on all patients and controls. RESULTS: RV peak longitudinal strain was increased in TOF patients with PR > 30 ml/m2 when compared to those with PR < 30 ml/m2 (- 22.5% ± 2.7% vs - 19.7% ± 3.5%, p = 0.018) and controls (p = 0.007). PR volume correlated with peak RV longitudinal strain (R = - 0.37, p = 0.030) and peak RV longitudinal strain rate (systolic: R = 0.37, p = 0.03; diastolic: R = 0.39, p = 0.021). The peak RV circumferential strain, from base to apex, increased more than in healthy controls (apex-base difference 7.6% ± 4.2% vs 3.3% ± 2.4%, p < 0.0001). CONCLUSIONS: Pediatric patients with TOF and a severe pulmonary regurgitation show an enhanced longitudinal strain when compared to patients with milder regurgitation or to control subjects. In addition, mean RV circumferential strain of the patients is significantly enhanced compared to healthy individuals.

Additional mechanism for left ventricular dysfunction: chronic pulmonary regurgitation decreases left ventricular preload in patients with tetralogy of Fallot.

BACKGROUND: Right ventricular dysfunction in patients with tetralogy of Fallot and significant pulmonary regurgitation may lead to systolic dysfunction of the left ventricle due to altered ventricular interaction. We were interested in determining whether chronic pulmonary regurgitation affects the preload of the left ventricle. In addition, we wanted to study whether severe chronic pulmonary regurgitation would alter the preload of the left ventricle when compared with patients having preserved pulmonary valve annulus. METHODS: The study group comprised 38 patients with tetralogy of Fallot who underwent surgical repair between 1990 and 2003. Transannular patching was required in 21 patients to reconstruct the right ventricular outflow tract. Altogether, 48 age- and gender-matched healthy volunteers were recruited. Cardiac MRI was performed on all study patients to assess the atrial and ventricular volumes and function. RESULTS: Severe pulmonary regurgitation (>30 ml/m2) was present in 13 patients, of whom 11 had a transannular patch, but only two had a preserved pulmonary valve annulus. The ventricular preload volumes from both atria were significantly reduced in patients with severe pulmonary regurgitation, and left ventricular stroke volumes (44.1±4.7 versus 58.9±10.7 ml/m2; p<0.0001) were smaller compared with that in patients with pulmonary regurgitation <30 ml/m2 or in controls. CONCLUSIONS: In patients with tetralogy of Fallot, severe pulmonary regurgitation has a significant effect on volume flow through the left atrium. Reduction in left ventricular preload volume may be an additional factor contributing to left ventricular dysfunction.

Need of transannular patch in tetralogy of Fallot surgery carries a higher risk of reoperation but has no impact on late survival: results of Fallot repair in Finland.

OBJECTIVES: Our study is a population-based evaluation of the long-term results after surgical repair for tetralogy of Fallot (TOF). All patients operated on in the country since the first procedure were identified via the Finnish research database of paediatric cardiac surgery and the Finnish population register. The follow-up was 99% completed due to comprehensive coverage of the registers. METHODS: The Finnish research database of paediatric cardiac surgery, surgical logs, diagnosis cards and computer files of the hospitals were used for data collection. The Finnish Population Register Center was used to obtain current patient status and dates of death and emigration. RESULTS: A total of 600 patients underwent surgical repair of TOF before the age of 15 years during the 46-year period from 1962 to 2007. The mean follow-up time was 23 ± 12.1 years; 513 (85%) patients were alive and living in Finland, 82 (14%) had died and 5 patients were lost to the follow-up (0.8%). A total of 40 patients (7%) died early (≤30 days) and 42 (7%) died late (>30 days) after the surgical correction. During the last two decades the early mortality rate was 1.5% and no early deaths were observed after the year 2000. A transannular patch (TAP) was used in the reconstruction of the right ventricular outflow tract in 191 (32%) of these patients and had no influence on late mortality but the event-free survival was significantly inferior in these patients. If a primary palliation was performed before the correction, the late survival was significantly inferior when compared with patients without initial palliation. Also reoperation was more common in patients with primary palliation. CONCLUSIONS: The long-term prognosis of surgically corrected TOF patients is good and has improved with each decade since the beginning of TOF surgery in Finland. Primary repair of tetralogy of Fallot predicts a lower mortality rate and longer freedom from reoperation when compared with two-stage repair. Need of a TAP in TOF surgery carries a higher risk of reoperation but has no impact on late survival.

Late gadolinium enhancement (LGE) progresses with right ventricle volume in children after repair of tetralogy of fallot.

BACKGROUND: Fibrosis after myocardial damage can be determined by cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE). We studied whether ventricular LGE is visible in the ventricles of pediatric and adolescent TOF (tetralogy of Fallot) patients by measuring LGE and investigating whether fibrosis correlated with right ventricular volume, pulmonary regurgitation, N-terminal pro-brain natriuretic peptide (NT-proBNP) or the aminoterminal propeptide of type III procollagen (PIIINP). We also studied if the patient's age, post-operative follow-up time or surgical history would affect LGE. METHODS: A total of 40 pediatric patients who had undergone TOF repair and 43 healthy age and gender matched controls underwent a CMR study, whereby LGE was scored in the right (RV) and the left ventricle. To exclude the possible iatrogenic scarring we calculated the LGE score by excluding the right ventricular outflow tract and VSD patch region. RESULTS: All patients had RV LGE and in 39 of 40 it was seen also outside the surgically affected areas. The amount of LGE correlated positively with the RV end-diastolic volume (r = 0.44, P = 0.0045), pulmonary regurgitation (r = 0.40, P = 0.013), and with NT-proBNP. The presence of LGE also depended on post-operative follow-up time (r = 0.53, P = 0.006). PIIINP levels of TOF patients were significantly higher than in the control subjects but it did not correlate with LGE or with any of the studied clinical markers. CONCLUSIONS: LGE is present globally in the right ventricular muscle in children and adolescents with TOF. The longer the follow-up time the more common was the LGE in the right ventricle.