Serial pulmonary vascular resistance assessment in patients late after ventricular septal defect repair.

BACKGROUND: The long-term evolution of pulmonary vascular resistance (PVR) after ventricular septal defect (VSD) repair is unknown. This study serially evaluated resting and exercise PVR after VSD repair in childhood. METHODS: Patients were enrolled from the outpatient Adult Congenital Heart Disease clinic of the University Hospitals Leuven and compared to age- and gender-matched controls. Participants underwent resting and exercise echocardiography and cardiopulmonary exercise testing at baseline and follow-up. Total PVR was calculated as the ratio of mean pulmonary artery pressure (mPAP) to cardiac output (CO). The slope of the mPAP-CO curve (exercise PVR) was obtained using linear regression analysis. RESULTS: Twenty-seven patients (mean age 31 ±â€¯7 years, 70% male) and 18 controls were included. At baseline, patients had larger right ventricular (RV) end-diastolic areas (10 ±â€¯2 vs 9 ±â€¯1 cm2/m2, p = 0.001) and lower tricuspid annular plane systolic excursion (TAPSE) (17 (17-19) vs 26 (22-28) mm, p < 0.001). After 1.1 (1.0-1.5) years follow-up, similar differences in RV areas and TAPSE were found. Patients reached lower peak workload and cardiac index compared to controls at each time point. Peak total PVR was higher (Baseline: 2.7 ±â€¯0.8 vs 2.2 ±â€¯0.3 mm Hg/L/min, p = 0.005; Follow-up: 2.9 ±â€¯0.9 vs 2.1 ±â€¯0.3 mm Hg/L/min, p < 0.001) and the mPAP-CO slope was steeper (Baseline: 2.2 ±â€¯0.8 vs 1.7 ±â€¯0.3 mm Hg/L/min, p = 0.008; Follow-up: 2.5 ±â€¯0.9 vs 1.6 ±â€¯0.3 mm Hg/L/min, p < 0.001) in patients. The mPAP-CO slope in patients correlated inversely with peak oxygen uptake (R = -0.41 and - 0.45, p = 0.036 and 0.022, baseline and follow-up, respectively). CONCLUSION: Despite repair, VSD patients seem to show altered pulmonary hemodynamics and RV impairment at rest and exercise, supporting life-long follow-up.

Advanced Imaging to Phenotype Patients With a Systemic Right Ventricle.

Background Reduced ventricular function and decreased exercise capacity are widespread in adults with complete transposition of the great arteries after atrial switch ( TGA -Mustard/Senning) and congenitally corrected TGA (cc TGA ). Advanced imaging techniques may help to better phenotype these patients and evaluate exercise cardiac response. Methods and Results Thirty-three adults with a systemic right ventricle (70% TGA -Mustard/Senning, 37±9 years of age, 24% female, 94% New York Heart Association class I- II ) underwent echocardiogram, cardiopulmonary exercise testing, and cardiovascular magnetic resonance imaging at rest and during a 4-stage free-breathing bicycle test. They were compared with 12 healthy controls (39±10 years of age, 25% female, all New York Heart Association class I). TGA -Mustard/Senning patients had a higher global circumferential strain (-15.8±3.6 versus -11.2±5.2%, P=0.008) when compared with cc TGA , whereas global longitudinal strain and systemic right ventricle contractility during exercise were similar in both groups. Septal extracellular volume ( ECV ) in cc TGA was significantly higher than in TGA -Mustard/Senning (30.2±2.0 versus 27.1±2.7%, P=0.005). During exercise, TGA -Mustard/Senning had a fall in end-diastolic volume and stroke volume (11% and 8%, respectively; both P≤0.002), whereas cc TGA could increase their stroke volume in the same way as healthy controls. Because of a greater heart rate reserve in TGA -Mustard/Senning ( P for interaction=0.010), cardiac index and peak oxygen uptake were similar between both patient groups. Conclusions Caution should be exercised when evaluating pooled analyses of systemic right ventricle patients, given the differences in myocardial contraction pattern, septal extracellular volume, and the exercise response of TGA -Mustard/Senning versus cc TGA patients. Longitudinal follow-up will determine whether abnormal exercise cardiac response is a marker of earlier failure.

Right ventricular systolic dysfunction at rest is not related to decreased exercise capacity in patients with a systemic right ventricle.

BACKGROUND: To evaluate the relationship between right ventricular (RV) systolic dysfunction at rest and reduced exercise capacity in patients with a systemic RV (sRV). METHODS: All patients with congenitally corrected transposition of the great arteries (ccTGA) or complete TGA after atrial switch (TGA-Mustard/Senning) followed in our institution between July 2011 and September 2017 who underwent cardiac imaging within a six-month time period of cardiopulmonary exercise testing (CPET) were analyzed. We assessed sRV systolic function with TAPSE and fractional area change on echocardiogram and, if possible, with ejection fraction, global longitudinal and circumferential strain on cardiac magnetic resonance (CMR) imaging. RESULTS: We studied 105 patients with an sRV (median age 34 [IQR 28-42] years, 29% ccTGA and 71% TGA-Mustard/Senning) of which 39% had either a pacemaker (n = 17), Eisenmenger physiology (n = 6), severe systemic atrioventricular valve regurgitation (n = 14), or peak exercise arterial oxygen saturation < 92% (n = 17). Most patients were asymptomatic or mildly symptomatic (NYHA class I/II/III in 71/23/6%). Sixty-four percent had evidence of moderate or severe sRV dysfunction on cardiac imaging. Mean peak oxygen uptake (pVO2) was 24.1 ±â€¯7.4 mL/kg/min, corresponding to a percentage of predicted pVO2 (%ppVO2) of 69 ±â€¯17%. No parameter of sRV systolic function as evaluated on echocardiography (n = 105) or CMR (n = 46) was correlated with the %ppVO2, even after adjusting for associated cardiac defects or pacemakers. CONCLUSIONS: In adults with an sRV, there is no relation between echocardiographic or CMR-derived sRV systolic function parameters at rest and peak oxygen uptake. Exercise imaging may be superior to evaluate whether sRV contractility limits exercise capacity.

Prognostic significance of improvement in right ventricular systolic function during cardiac resynchronization therapy.

Objectives There is conflicting evidence concerning the role of right ventricular (RV) systolic dysfunction in the long-term clinical outcome after cardiac resynchronization therapy (CRT). Therefore we aimed to assess evolution of RV systolic function during CRT, covariates associated with its improvement, and its impact on outcome. Methods and results All CRT device implantations (Jan 2009-Dec 2011) in our institution were reviewed. Records of 69 patients (25% female, mean age 62.8 ± 9.2 years, mean left ventricular (LV) ejection fraction 27 ± 8%) were analyzed. Baseline RV fractional area change (FAC) < 35% was present in 37 patients (54%). At one year, 24 of them (65%) improved in RV FAC. LV remodeling and mitral regurgitation were significantly associated with the likelihood of RV FAC improvement (OR 4.80, 95% CI 1.13-20.46, P = 0.034 and OR 0.32, 95% CI 0.12-0.89, P = 0.029, respectively). The composite endpoint of death or heart transplantation occurred in 23 patients (33%) over a mean follow-up of 2.8 ± 1.4 years. RV FAC at one year (HR 0.90, 95% CI 0.86-0.94, P < .001) was, independently of NYHA class and LV remodeling, associated with clinical outcome. Conclusions RV systolic function might improve during CRT. This seems mainly due to changed left-sided hemodynamics and LV remodeling. Good RV systolic function is independently related with better outcome.

Appearance of QRS fragmentation late after Mustard/Senning repair is associated with adverse outcome.

OBJECTIVE: To evaluate if development of fragmented QRS (fQRS) complexes, a marker of inhomogeneous ventricular activation due to myocardial fibrosis, is associated with adverse outcome in adults after Mustard/Senning repair for d-transposition of the great arteries (d-TGA). METHODS: Adults with atrial switch repair for d-TGA were selected from the database of a tertiary care hospital. Exclusion criteria were systemic right ventricular (RV) assist device or heart transplantation (HTx) before the age of 16, or fQRS already present at first visit to the Adult Congenital Heart Disease clinic. A blinded expert reader retrospectively analysed all available ECGs after the age of 16 for the presence of fQRS. The appearance of fQRS was modelled for each patient as a time-dependent variable. Cox regression was performed to assess the relationship between covariates and the composite endpoint of cardiovascular mortality, HTx or systemic RV assist device. RESULTS: Records of 89 patients (34% female, 42% Mustard repair) were analysed. At latest follow-up, fQRS was noted in 26 patients (29%). Over a median follow-up time of 16.9 (IQR 12.6-22.9) years, the composite endpoint occurred in nine patients (10%). In multivariable Cox analysis, appearance of fQRS (HR 14.11; 95% CI 1.42 to 140.12) and development of severe RV dysfunction (HR 11.36; 95% CI 2.08 to 62.17) were significantly associated with the composite endpoint. CONCLUSIONS: Appearance of fQRS complexes on a 12-lead ECG is associated with adverse outcome in adults after atrial switch repair for d-TGA. In this population, fQRS detection might be a promising and easily implementable tool to identify patients at risk for adverse events.

Long-Term Outcome of Patients with Perimembranous Ventricular Septal Defect: Results from the Belgian Registry on Adult Congenital Heart Disease.

OBJECTIVES: Studies evaluating the long-term outcome of adults with ventricular septal defect (VSD) are important to inform patients about prognosis. This study investigated the long-term outcome of patients with perimembranous VSD (pmVSD) followed in the Belgian Registry on Adult Congenital Heart Disease. METHODS: All pmVSD patients in the registry were analyzed. RESULTS: Two hundred and sixty-six patients were studied. Fifteen patients had Eisenmenger syndrome. One hundred and seventy-three had isolated pmVSD and 78 had pmVSD with concomitant lesions. Of the patients with isolated pmVSD, 52% were male, median age was 29 years (IQR 24-35 years) and median follow-up duration was 18 years (IQR 10-25 years). Fifty-three (31%) patients underwent VSD closure and 10 (19%) had a residual shunt. Most (93%) patients were in NYHA class I. No patients died. Two (4%) patients developed atrial arrhythmia and 2 (4%) required pacemaker implantation. Seven (14%) developed left ventricular outflow tract obstruction (LVOTO). In the unrepaired pmVSD group, 4 developed endocarditis. In the entire group, moderate or severe aortic regurgitation (AR) occurred in 9 (5%) patients. CONCLUSIONS: Long-term survival in patients with isolated pmVSD was not uneventful. Moderate or severe AR might develop and endocarditis occurred in patients without VSD repair. Complications after VSD closure included atrial arrhythmia, pacemaker implantation and LVOTO.

Recall of patients discharged from follow-up after repair of isolated congenital shunt lesions.

BACKGROUND: Discharge from follow-up after closure of isolated congenital shunt lesions in childhood was common practice in the past. The aim of the present study was to recall these patients to evaluate their current status. METHODS: Patients included in the database of pediatric and congenital heart disease of our tertiary center with repaired secundum atrial septal defect (ASD) or ventricular septal defect (VSD) before the age of 18years, and discharged from follow-up, were invited for clinical and echocardiographic check-up. RESULTS: Forty-six ASD patients (age 30±7years, 37% male) responded. Median age at ASD repair was 6 (IQR 4-8) years. All but one functioned in NYHA class I. Eight (17%) patients reported palpitations. No patient developed pulmonary hypertension (PH). Right ventricular (RV) dilatation was present in 7 (15%). RV fractional area change (FAC) was <35% in 7 (15%), TAPSE <17mm in 12 (26%). Forty-seven VSD patients (age 34 (IQR 29-40) years, 57% male) participated. Median age at VSD repair was 4 (IQR 1-5) years. Six (13%) patients functioned in NYHA class II. Seventeen (36%) patients reported palpitations. Four (9%) patients presented PH. Left ventricular dilatation was present in 4 (9%), RV dilatation in 6 (13%). RV FAC was <35% in 7 (15%), TAPSE <17mm in 17 (36%). Seven (15%) patients had dilated ascending aorta. CONCLUSIONS: Patients with closure of isolated secundum-type ASD in childhood do well, but some have persistent RV dilatation and dysfunction. By contrast, more patients after VSD closure were symptomatic and presented with RV dilatation and dysfunction, PH, and a dilated ascending aorta.

Pulmonary outflow obstruction protects against heart failure in adults with congenitally corrected transposition of the great arteries.

BACKGROUND: Pulmonary outflow tract obstruction (POTO) reduces systemic atrioventricular valve (SAVV) regurgitation severity in congenitally corrected transposition of the great arteries (ccTGA). Therefore, pulmonary artery banding is proposed as a palliative intervention. We aimed to investigate the effect of native or surgically induced POTO on event-free survival, defined as the composite of all-cause mortality, heart transplantation, or congestive heart failure (CHF). METHODS AND RESULTS: Patients with ccTGA (n=62; median age 27.5 (IQR 18.4-39.4) years; 39% with POTO) were selected from the Adult Congenital Heart Disease database of a tertiary hospital. At first visit, SAVV regurgitation ≥ 3/4, systemic RV dysfunction ≥ moderate, and CHF were present in 26%, 26%, and 15% of patients, respectively. Over a mean follow-up time of 10.1 ± 6.1 years, all-cause mortality, rate of heart transplantation, and CHF were 18%, 8% and 40%, respectively. SAVV regurgitation (HR: 1.99; 95% CI: 1.01-3.92; P=0.048) and systemic RV dysfunction severity (HR: 1.89; 95% CI: 1.05-3.37; P=0.033) were associated with the composite endpoint, independently of age at baseline, POTO, Ebstein-like malformation, and systemic RV dilatation. Patients with POTO had lower risk for developing SAVV regurgitation ≥ 3/4 (HR: 0.18; 95% CI: 0.05-0.58; P=0.004) and moderate systemic RV dysfunction (HR: 0.34; 95% CI: 0.15-0.78; P=0.011). When POTO was present, the mean progression-free interval for the composite endpoint increased from 11.2 to 18.1 years (P=0.035). CONCLUSIONS: POTO is associated with an improved event-free survival in adults with ccTGA.

Additional tricuspid annuloplasty in mitral valve surgery results in better clinical outcome.

OBJECTIVE: The clinical benefit of tricuspid annuloplasty (TA) in patients undergoing mitral valve surgery (MVS) is still debated. We evaluated the immediate surgical success, postoperative outcome and the medium-term effect of TA in MVS. METHODS: Patients were included between September 2003 and December 2009 and followed until September 2013 to achieve a median follow-up time of 5 years (IQR 3.7-6.9). The end point of mortality due to cardiac causes and combined end point of cardiac mortality or hospitalisation for heart failure were evaluated. Propensity score adjusted Cox regression was used to evaluate the clinical benefit of TA at the time of MVS. RESULTS: Of 150 patients (84 female; 67±12 years), 82 presented with tricuspid regurgitation (TR) <2/4 and underwent isolated MVS. Of 68 patients presenting with TR≥2/4, 31 underwent isolated MVS whereas 37 underwent additional TA. In patients with preoperative TR≥2/4, TR was significantly reduced until 5 years postoperatively (mean reduction 0.81±1.31; p=0.04) when additional TA was done. The combined end point occurred in 29% vs 6% at 1 year and in 57% vs 39% at 5 years follow-up for patients with isolated MVS and patients undergoing concomitant TA, respectively. Patients with preoperative TR≥2/4 had worse unadjusted survival than those with TR<2/4 (logrank p=0.009). In the patients with TR≥2/4, propensity score-adjusted risk for the combined end point was higher in those with isolated MVS versus MVS with additional TA (Cox HR 2.855 (1.082-7.532), p=0.035). CONCLUSIONS: Additional TA is an effective surgical measure to reduce functional TR severity. This approach results in a decreased risk of cardiac mortality and hospitalisation in patients with preoperative TR≥2/4.

Clinical significance of dynamic pulmonary vascular resistance in two populations at risk of pulmonary arterial hypertension.

AIMS: Patients at risk of pulmonary arterial hypertension (PAH) may present with abnormal dynamic pulmonary vascular resistance (PVR) during exercise. However, its clinical significance remains unclear. The present study aimed at analysing the meaning of dynamic PVR in two populations at risk of PAH: secundum atrial septal defect (ASD) and systemic sclerosis (SSc). METHODS AND RESULTS: Adult patients with corrected ASD were consecutively selected from the database of Pediatric and Congenital Heart Disease of the University Hospitals Leuven. Patients with SSc were consecutively selected from the rheumatology database of the University Hospital Liège. At inclusion, all underwent a rest and bicycle stress echocardiography to obtain baseline right heart characteristics and dynamic PVR. Routine follow-up echocardiography was performed. Twenty-eight patients with corrected ASD (mean age 41 ± 17 years, 79% female) were followed for a median time of 3.7 [inter-quartile range (IQR) 2.9-4.1] years. No patient developed PAH. Dynamic PVR was significantly associated with right atrial dilatation at latest follow-up (Spearman's ρ 0.51, P = 0.013). Forty-five SSc patients (mean age 54 ± 13 years, 76% female) were followed for a median time of 2.4 (IQR 0.8-2.9) years. Thirteen patients (30%) developed PAH. Dynamic PVR was the only independent predictor of PAH (hazards ratio 1.22, 95% confidence interval 1.01-1.47). No significant right heart morphometric changes occurred. CONCLUSION: Dynamic PVR predicted PAH development in patients with SSc, whereas dynamic PVR was associated with right heart morphometric changes after ASD closure. The predictive role of dynamic PVR might depend on the underlying disease type. Larger studies are needed to confirm this hypothesis.

Right heart morphology in elevated pulmonary artery pressure: relationship between echocardiographic and right heart catheterization data.

BACKGROUND: When elevated pulmonary artery pressure (PAP) is assessed by echocardiography, right heart morphology is always considered. The goal of this study was to evaluate how right heart geometry changes with increasing right ventricular pressure load. SUBJECTS AND METHODS: Data from patients undergoing transthoracic echocardiography with subsequent right heart catheterization within a time period of 6 months were retrospectively analysed. First, Spearman-rho coefficients between mean PAP and right heart parameters were calculated. Second, the population was divided into tertiles according to mean PAP and Kruskal-Wallis variance analysis between variables was performed. RESULTS: Fifty-four patients (23 female, median age 77 years, IQ range 63-83) were selected. Mean PAP (median 27 mmHg, IQ range 24-36), right atrial (RA) dilatation (median 1, IQ range 0-2), tricuspid insufficiency (TI) severity (median 1.5, IQ range 0-2) and right ventricular (RV) dilatation (median 0, IQ range 0) were included. Significant correlations with mean PAP were found for RA dilatation (rho = 0.380; P = 0.005) and TI severity (rho = 0.294; P = 0.032). No correlation with RV dilatation could be shown (rho = 0.241; P = 0.081). Across the tertiles [(1) mean PAP 25 mmHg; (2) mean PAP 26-30 mmHg; (3) mean PAP > or = 31 mmHg)], variance analysis showed a significant increase in RA dilatation (P = 0.009) and TI severity (P = 0.040). No change in RV dilatation across groups was observed (P = 0.216). CONCLUSIONS: RA dilatation and TI severity significantly increase with increasing RV pressure load. No increase in RV dilatation was observed in the studied population. Hence, absence of RV dilatation does not exclude the presence of elevated PAP.

A different view on predictors of pulmonary hypertension in secundum atrial septal defect.

BACKGROUND/OBJECTIVES: Pulmonary arterial hypertension is an important complication in hemodynamically relevant atrial septal defects (ASD) and negatively affects outcome. This retrospective study aimed at (1) estimating the prevalence of pulmonary hypertension (PH) in patients with secundum ASD and (2) identifying predictors of PH development or persistence after ASD closure. METHODS: Consecutive patients with an isolated secundum ASD from the Belgian Registry on Adult Congenital Heart Disease were studied. Demographic, clinical, echocardiographic and invasive hemodynamic measurements were analyzed. PH was defined upon the echocardiographic PH probability (tricuspid regurgitation velocity≥2.9 m/s). RESULTS: PH prevalence in the entire ASD population (295 patients, 68.8% females, mean age 46±21 years) was 15.9% compared to 13.3% in patients after ASD closure. PH after ASD closure was significantly related to mortality (p=0.001), atrial arrhythmia (p<0.001) and right heart failure (p=0.019). Age at repair was the most important predictor for PH (HR 1.11). In the highest tertile of age at repair (>55 years), PH prevalence was the highest (34%) and mean pulmonary artery pressure (mPAP) at catheterization before was related to PH after closure (HR 1.09). Twenty patients in the PH group had mPAP<25 mmHg before closure. CONCLUSIONS: PH in closed secundum ASD patients is not uncommon. Its prevalence was the highest when the defect was repaired above 55 years of age. Clinical outcome was worse. PH may even develop despite normal mPAP before closure. The present findings raise the question whether the cutoff value for mPAP before closure should be age-adjusted.

Functional and haemodynamic assessment of mild-to-moderate pulmonary valve stenosis at rest and during exercise.

OBJECTIVE: In adult patients with mild-to-moderate pulmonary valve (PV) stenosis, exercise capacity and haemodynamics have not been extensively studied, although regular exercise is recommended. Therefore, we aimed to assess exercise capacity to study the increase in PV gradient during exercise and to evaluate the impact of this increased pressure load on the RV. METHODS: Nineteen patients (8 female; 29±6.4 years) with isolated mild-to-moderate PV stenosis and no prior cardiac interventions were consecutively enrolled from the outpatient clinic of adult congenital heart disease. All patients underwent cardiopulmonary exercise testing, transthoracic echocardiography and bicycle stress echocardiography. Results for exercise testing were compared with age-matched and gender-matched control patients. RESULTS: In the studied population, resting heart rate (89±11 vs 75±14 bpm; p=0.001), peak power (199±66 vs 263±68 W; p=0.006); peak VO2 (31.2±9.9 vs 39±7.4 mL/kg/min; p=0.011); oxygen uptake efficiency slope (2430±913 vs 3292±943(mL/min)/(L/min); p=0.007) and VE/VCO2 slope (26.8±5.2 vs 22.6±4.3; p=0.01) differed significantly from controls. A linear increase of peak PV gradient with increasing flow was observed in the pooled dataset (Pearson's R=0.947; p<0.0001) and slopes identical as for control patients were obtained for the oxygen pulse-workload relationship. Right heart morphology and function were preserved in the studied patients. CONCLUSIONS: Patients with mild-to-moderate PV stenosis have decreased exercise capacity. A linear increase in PV gradient with flow suggests a fixed valve area throughout the exercise. Although systolic RV pressure load increases during exercise, good ventricular performance was observed without signs of functional or morphological changes of the right heart. CLINICAL TRIAL NUMBER: NCT01444222.

Doubly committed ventricular septal defect: single-centre experience and midterm follow-up.

BACKGROUND: Doubly committed ventricular septal defect (dcVSD) is the least common type of VSD. Because published studies are rather scarce, this study aimed at evaluating the midterm outcome of dcVSDs. METHODS: The records of all patients registered in the database of Paediatric and Congenital Cardiology, University Hospitals Leuven, with a dcVSD at 16 years of age were reviewed. Clinical, electrocardiographic and transthoracic echocardiographic changes from baseline, defined as of the age of 16 years, until the latest follow-up were compared. RESULTS: Thirty-three patients (20 males, median age 26 years, interquartile range 12) were followed for a median time of 7.9 years (interquartile range 9.8, time range 2-25.9). No deaths occurred. In 15 patients (45%), the defect remained patent at baseline. During follow-up, two spontaneous closures (13%) occurred. Eighteen patients (55%) required closure before the age of 16 years. Five (28%) needed reoperation. In the dcVSD closure group, left ventricular ejection fraction decreased from 69 ± 12 to 61 ± 6% (p = 0.028). No significant changes in pulmonary arterial hypertension were noticed. CONCLUSIONS: Patients with persistently patent dcVSD remained nearly event free during follow-up. Event-free survival after dcVSD closure was markedly lower. These patients developed reduced left ventricular function and had a high risk of reintervention.