Standard and Strain Measurements by Echocardiography Detect Early Overloaded Right Ventricular Dysfunction: Validation against Hemodynamic and Myocyte Contractility Changes in a Large Animal Model.

BACKGROUND: Early detection of right ventricular (RV) failure is required to improve the management of patients with congenital heart diseases. The aim of this study was to validate echocardiography for the early detection of overloaded RV dysfunction, compared with hemodynamic and myocyte contractility assessment. METHODS: Using a porcine model reproducing repaired tetralogy of Fallot, RV function was evaluated over 4 months using standard echocardiography and speckle-tracking compared with hemodynamic parameters (conductance catheter). Sarcomere shortening and calcium transients were recorded in RV isolated myocytes. Contractile reserve (ΔEmax) was assessed by ß-adrenergic stimulation in vivo (dobutamine 5 µg/kg) and ex vivo (isoproterenol 100 nM). RESULTS: Six operated animals were compared with four age- and sex-matched controls. In the operated group, hemodynamic RV efficient ejection fraction was significantly decreased (29.7% [26.2%-34%] vs 42.9% [40.7%-48.6%], P < .01), and inotropic responses to dobutamine were attenuated (ΔEmax was 51% vs 193%, P < .05). Echocardiographic measurements of fraction of area change, tricuspid annular plane systolic excursion, tricuspid annular peak systolic velocity (S') and RV free wall longitudinal systolic strain and strain rate were significantly decreased. Strain rate, S', and tricuspid annular plane systolic excursion were correlated with ΔEmax (r = 0.75, r = 0.78, and r = 0.65, respectively, P < .05). These alterations were associated in RV isolated myocytes with the decrease of sarcomere shortening in response to isoproterenol and perturbations of calcium homeostasis assessed by the increase of spontaneous calcium waves. CONCLUSIONS: In this porcine model, both standard and strain echocardiographic parameters detected early impairments of RV function and cardiac reserve, which were associated with cardiomyocyte excitation-contraction coupling alterations.

Long-term outcomes of pulmonary arterial hypertension under specific drug therapy in Eisenmenger syndrome.

BACKGROUND: The long-term effectiveness of pulmonary arterial hypertension-specific drug therapy (PAH-SDT) in Eisenmenger syndrome is controversial. We investigated short-term and long-term hemodynamic changes under PAH-SDT and their associations with outcomes in a bicentric cohort. METHODS: Over 20 years, we included 69 patients with congenital heart disease, an indexed pulmonary vascular resistance (PVRi) >8 WU·m2, and 292 standardized catheterizations at baseline and after PAH-SDT initiation or intensification. Oxygen consumption was measured and the Fick principle applied to calculate indexed pulmonary output (Qpi) and PVRi. RESULTS: After PAH-SDT initiation or intensification, median (interquartile range) PVRi decrease was 5.1 WU·m2 (-1.4, -12.6) (p < 0.0001). Median Qpi and 6-minute walk test increases were +0.4 liter/min/m2 (0.0, +0.9) (p < 0.0001) and +49 m (+15, +93) (p = 0.0003), respectively. Hemodynamic response combining increased Qpi with decreases in transpulmonary gradient and PVRi occurred in 68.0% of patients. After a median of 4.9 years, PVRi and Qpi changes were no longer significant. Over a median of 7.2 years, 23 (33.3%) patients met a composite criterion (death, n = 8; heart-lung transplantation or listing for transplantation, n = 15). The 15-year cumulative event rate was 49.2%. By multivariate analysis, independent predictors of events were superior vena cava oxygen saturation and hemodynamic response (p = 0.048 and p < 0.0001). CONCLUSIONS: In Eisenmenger syndrome, PAH-SDT induces early hemodynamic improvements, which decline over time. Hemodynamic changes under PAH-SDT vary across patients. Hemodynamic parameters at baseline and under PAH-SDT are associated with events. PAH-SDT may need to be individualized based on hemodynamic changes.

The mid-term outcome of primary open valvotomy for critical aortic stenosis in early infancy - a retrospective single center study over 18 years.

BACKGROUND: The objective of this study was to examine early and long-term results of surgical aortic valvotomy in neonates and infants aged less than four months and to identify predictors of outcome. METHODS: Between August 1994 and April 2012, 83 consecutive patients younger than 4 months of age underwent open heart valvotomy for critical aortic stenosis in our institution. Median age was 17 days (range 0-111 days). We examined clinical records to establish determinants of outcome and illustrate long-term results. RESULTS: Fifty-six patients (67 %) were neonates. Associated cardiac malformations were found in 24 patients (29 %), including multilevel left heart obstruction in 5. The median follow-up was 4.2 years. The time-related survival rate was 87 and 85 % at 5 and 15 years, respectively. The time-related survival without reintervention was respectively 51, 35 and 18 % at 5, 10 and 15 years. The time-related survival without aortic valve replacement was respectively 67, 54 and 39 % at 5, 10 and 15 years. Ventricular dysfunction (p = 0.04), delayed sternal closure (p = 0.007), endocardial fibroelastosis (p = 0.02) and low z-score of the aortic annulus (p = 0.04) were found predictors of global mortality. Ventricular dysfunction (p = 0.01) and endocardial fibroelastosis (p = 0.04) were found predictors of reintervention. CONCLUSIONS: The experience, in our center, on the management of critical aortic stenosis, shows a low early and late mortality, but the aortic valvotomy is a palliative procedure and we see unfortunately a high rate of reintervention among which the aortic valve replacement. These results suggest to reconsider the use of aortic balloon valvotomy, and particularly for the neonates with a low cardiac output in order to avoid the myocardial stress and the neurological injury due to the cardiopulmonary bypass.

Long-term outcomes of the arterial switch operation for transposition of the great arteries and ventricular septal defect and/or aortic arch obstruction.

OBJECTIVES: Long-term outcomes after the arterial switch operation (ASO) for complex transposition of the great arteries (TGA) should be clarified. METHODS: A retrospective study was conducted in patients operated on between 1982 and 1998. Overall 220 postoperative survivors, 79.1% with a ventricular septal defect, 13.2% with multiple ventricular septal defects, and 29.1% with aortic arch obstruction, were followed for 17 years (0-28 years). RESULTS: The conditional survival rate was 96.7% [95% confidence interval (CI): 94.4-99.1] at 25 years. Late sudden death occurred in 2 asymptomatic patients. The cumulative incidence rate of death or reinterventions was 3.8% (95% CI: 2.9-4.8) at 25 years, with age at ASO <10 days and aortic regurgitation at discharge identified as independent risk factors. The cumulative incidence rate of neoaortic regurgitation was 41.6% (95% CI: 20.5-62.8) at 25 years with an aorto-pulmonary diameter mismatch at the time of the ASO, age at ASO <10 days and aortic regurgitation at discharge identified as independent risk factors. At the last follow-up, 53 patients (24.1%) had neoaortic root dilatation with an aortic sinus z-score ≥3 and 6 of them had a Bentall operation at a median delay of 14.1 years since the ASO. The only independent factors for neoaortic root dilatation were male sex and an aorto-pulmonary diameter mismatch at the time of the ASO. CONCLUSIONS: Despite a continual rate of reinterventions, long-term survival and cardiovascular outcome are excellent after ASO for complex TGA. Dilatation of the neoaortic root and neoaortic regurgitation may be observed with time and 2 late sudden deaths occurred, justifying a close follow-up in all patients.

Subaortic Area at Risk for Development of Obstruction After Surgical Repair of Atrioventricular Septal Defect: Myth or Reality?

BACKGROUND: Morphology of the left ventricular outflow tract (LVOT) in atrioventricular septal defects (AVSDs) has been reported to be at risk for development of obstruction. The purpose of the present study was to identify the incidence, the risk factors, and the surgical outcomes of subaortic stenosis in repaired AVSDs. METHODS: Records of 427 consecutive patients who underwent anatomical repair for all types of AVSDs from January 2000 to December 2012 were reviewed. Outcomes, independent risk factors, reoperation, and death were analyzed. RESULTS: In a median follow-up of five years (range: 17 months-11.8 years), eight patients required nine reoperations for subaortic stenosis. Study group (n = 11) included three additional patients for whom repair was performed in a different institution. Median delay for reoperation was 11.9 years (range: 1.3-19.4 years). Surgical relief of subaortic stenosis was obtained by means of the enlargement of the LVOT: resection of fibrous structures in all reoperated patients and associated with septal myectomy in four. Two patients required a modified Konno procedure. Five reoperations were associated with left atrioventricular valve repair or replacement. Statistical analysis didn't reveal any morphologic or demographic risk factors. No early or late death occurred. CONCLUSION: The development of subaortic stenosis after repair of AVSD remains a rare complication in midterm follow-up (incidence: 1.9%). The performance of preventive gesture during repair seemed to be unjustified. The surgical management of this reoperation consists of a simple and safe procedure.

Critical Congenital Heart Diseases in Preterm Neonates: Is Early Cardiac Surgery Quite Reasonable?

Prematurity is a recognized risk factor for morbidity and mortality following cardiac surgery. Postoperative and long-term outcomes after cardiac surgery performed in the preterm period are poorly described. The aim of this study was to analyze a population of preterm neonates operated on for critical congenital heart disease (CHD) before 37 weeks of gestational age (wGA) with special attention given to early and late mortality and morbidity. Between 2000 and 2013, 28 preterm neonates (median gestational age (GA) 34.3 weeks) underwent cardiopulmonary bypass (CPB) surgery for critical CHD before 37 wGA; records were retrospectively reviewed. All patients except three with single ventricle physiology had a single-stage anatomic repair. Overall mortality was 43 % (95 % CI 25-62). Risk factors for death were birth weight (p = 0.032) and weight at surgery (p = 0.037), independently of GA, preoperative status, CPB and aortic clamp time. Seven patients, including those with univentricular hearts, died during the postoperative period, and five in the first year after surgery. Median follow-up was 5.9 years (range 1 month-12.8 years). Kaplan-Meier survival rate was 75 % (95 % CI 59-91) at 1 month, and 57 % (95 % CI 39-75) at 1 and 5 years. Eight patients required reoperations after a delay of 2.8 ± 1.3 months; eight had bronchopulmonary dysplasia. At the end of follow-up, nine patients were asymptomatic. One-stage biventricular repair for critical CHD on preterm neonates was feasible. Mortality remained high but acceptable, mainly confined to the first postoperative year and related to small weight. Despite reoperations, long-term clinical status was good in most survivors. Further long-term prospective investigations are necessary to evaluate neurodevelopmental outcomes.

Diagnosis of functionally significant coronary stenosis with exercise CT myocardial perfusion imaging.

PURPOSE: To assess the feasibility of exercise perfusion computed tomography (CT) in patients suspected of having hemodynamically significant coronary stenosis. MATERIALS AND METHODS: This study had institutional review board approval, and all patients gave informed consent. Thirty-two consecutive patients (26 men [mean age, 63 years] and six women [mean age, 71 years]) with 55 coronary stenoses of at least 50% underwent coronary CT angiography (one stenosis in 13 patients, two stenoses in 15 patients, and three stenoses in four patients). CT myocardial perfusion imaging was performed within 1 minute after patients performed supine exercise on an ergometer secured to the CT table. The pressure-rate product was computed to assess level of exercise. The myocardial enhancement ratio between stenotic and normally perfused territories was determined for each stenosis. Fractional flow reserve less than 0.8, as measured during invasive coronary angiography, was the reference for defining significant stenoses. Receiver operating characteristic curves were constructed to determine the myocardial enhancement ratio cutoff value. RESULTS: In the per-patient analysis, a myocardial enhancement ratio cutoff of 0.8 performed best for identifying functionally significant stenosis: Sensitivity was 95% (21 of 22 patients), specificity was 90% (nine of 10 patients), positive predictive value was 95% (21 of 22 patients), negative predictive value was 90% (nine of 10 patients), and accuracy was 94% (30 of 32 patients). Corresponding values in the per-stenosis analysis were 97% (29 of 30 stenoses), 96% (23 of 24 stenoses), 97% (29 of 30 stenoses), 96% (23 of 24 stenoses), and 96% (52 of 54 stenoses), respectively. CONCLUSION: Exercise CT myocardial perfusion imaging is feasible and accurate for assessment of the functional significance of coronary stenosis.

Right ventricular failure secondary to chronic overload in congenital heart diseases: benefits of cell therapy using human embryonic stem cell-derived cardiac progenitors.

OBJECTIVE: Despite the increasing incidence of right ventricular (RV) failure in adult patients with congenital heart disease, current therapeutic options are still limited. By contrast to left-heart diseases, cell-based myocardial regeneration applied to the right ventricle is poorly studied, even though it may be a therapeutic solution. As human embryonic stem cell-derived cardiac progenitors seem to be good candidates owing to their proliferation capacity, our aim was to assess, in a large animal model of overloaded RV dysfunction, the feasibility and effects of such a cell therapy. METHODS: Human MesP1(+)/SSEA-1(+) cardiogenic mesodermal cells were administered using multiple intramyocardial injections 4 months after a surgical procedure mimicking the repaired tetralogy of Fallot, and their effects were observed 3 months later on hemodynamic, rhythmic, and histologic parameters. RESULTS: All pigs (sham n = 6, treated n = 6) survived without complication, and cell therapy was clinically well tolerated. Although functional, contractility, and energetics parameters evolved similarly in both groups, benefits regarding arrhythmic susceptibility were observed in the treated group, associated with a significant decrease of peri-myocyte fibrosis (5.71% ± 2.49% vs 12.12% ± 1.85%; P < .01) without interstitial fibrosis change (5.18% ± 0.81% vs 5.49% ± 1.01%). Such a decrease could be related to paracrine effects, as no human cells could be detected within the myocardium. CONCLUSIONS: Cell therapy using intramyocardial injections of human MesP1(+)/SSEA-1(+) cardiogenic mesodermal cells seems to have benefits regarding overloaded RV tissue remodeling and arrhythmic susceptibility, but this mode of administration is not sufficient to obtain a significant improvement in RV function.

Late outcomes after arterial switch operation for Taussig-Bing anomaly.

OBJECTIVE: To assess the long-term results of the arterial switch operation (ASO) for Taussig-Bing Anomaly (TBA) and identify risk factors affecting outcomes. METHODS: Retrospective review and late follow-up was performed for all TBA patients from 1997 to 2010 (follow-up >3 years). Selection criteria included the absence of mitro-pulmonary continuity. RESULTS: Sixty-nine children underwent ASO at a median age of 24 days (interquartile range [IR] 11-125), with concomitant repair of aortic arch obstruction in 26 (37.7%). Complex coronary anatomy (n = 38; 55.0%) was common. Nine (13.0%) patients had staged repair. Hospital mortality was 5.8% (95% confidence interval [CI], 1.6%-14.2%; n = 4). Median follow-up was 11.2 years (IR 7.2-13.8). Subsequent mortality was confined to the first postoperative year (n = 5, 86% [95% CI, 78%-95%]), 1-, and 10-year survival). Overall mortality was related to coronary pattern (Yacoub types C and E vs A and D, multivariate, hazard ratio [HR] 12.2 [95% CI, 1.2-122.1], P = .03). At latest follow-up, 96% of the survivors are asymptomatic, with normal ventricular function. Cumulative incidence of reintervention at 10 years was 53% (95% CI, 28%-77%). Concomitant aortic arch obstruction was a predictor of reintervention (multivariate, HR 2.9 [95% CI, 1.1-7.4], P = .03). No mortality occurred upon reinterventions. CONCLUSIONS: In the largest series to date of ASO for TBA, mortality is confined to the first postoperative year, and related to coronary artery pattern. Beyond the first year, needed reinterventions are frequent, but with sustained functional status and no mortality over >10 years follow-up. Aortic arch obstruction is the main predictor for reintervention. Despite a significant rate of early events, favorable long-term outcomes argue for use of the ASO in TBA patients.

The modified Fontan procedure with use of extracardiac conduit in adults: analysis of 32 consecutive patients.

BACKGROUND: Uncommonly, adults with functionally univentricular hearts are becoming candidates for a Fontan procedure. The purpose of this study was to evaluate the course of patients undergoing the modified Fontan procedure with an extracardiac conduit in recent years. METHODS: Between January 2003 and December 2013, 32 adult patients (17 female and 15 male) underwent total cavopulmonary connection (TCPC) with extracardiac conduit. The median age at procedure was 24.5 years (interquartile range [IQR] 20 to 33 years). The diagnoses included double-inlet left ventricle (DILV) in 10 patients (31.2%), tricuspid atresia in 8 patients (25%), double-outlet right ventricle in 4 patients (12.5%), heterotaxia in 4 patients (12.5%), and mitral atresia in 2 patients (6.2%). Seventy-eight percent of patients had undergone at least one prior palliative procedure; the most common procedures were Blalock-Taussig shunt (16 patients), superior cavopulmonary shunt (12 patients), and pulmonary artery banding (6 patients). All patients underwent cardiac catheterization preoperatively. Aortic cross-clamping was necessary in 15 patients for intracardiac procedures. Fenestration was required in 9 patients (28%). Four concomitant intraoperative cryoablation procedures were performed. RESULTS: There was no hospital mortality. One patient (3.1%) died 6 months after undergoing TCPC. Morbidities included prolonged pleural effusion lasting more than 7 days in 20 patients (62.5%), atrial arrhythmias in 4 patients (12.5%), and permanent pacemakers in 3 patients (9.3%). The median follow-up time was 33 months (interquartile range [IQR], 10.5 to 50 months). Actuarial survival was 91.83% (95% confidence limits, 71.07 to 97.89) at 1 year and 5 years. Ninety-two percent of patients were in New York Heart Association class I or II at follow-up. The median postoperative oxygen saturation was 95% (IQR, 93% to 95.5%). Cardiac arrhythmia occurred in 4 patients. Systolic ventricular function improved during follow-up for all patients except 1 patient, who underwent cardiac transplantation 7 months after the TCPC. CONCLUSIONS: The modified Fontan procedure with use of an extracardiac conduit can be performed in adults with encouraging early and midterm results. The majority of late survivors had improved quality of life. The incidence of late death, reoperation, arrhythmias, and thromboembolic events was low during follow-up.

Transcatheter closure of large atrial septal defects: feasibility and safety in a large adult and pediatric population.

BACKGROUND: Data are needed on the safety and efficacy of device closure of large atrial septal defects. METHODS AND RESULTS: Between 1998 and 2013, 336 patients (161 children <15 years) with large, isolated, secundum atrial septal defects (balloon-stretched diameter ≥34 mm in adults or echocardiographic diameter >15 mm/m(2) in children) were managed using the Amplatzer device, at the Marie Lannelongue Hospital. Transthoracic echocardiographic guidance was used starting in 2005 (n=219; 65.2%). Balloon-stretched diameter was >40 mm in 36 adults; mean values were 37.6±3.3 mm in other adults and 26.3±6.3 mm/m(2) in children. Amplatzer closure was successful in 311 (92.6%; 95% confidence interval, 89%-95%) patients. Superior and posterior rim deficiencies were more common in failed than in successful procedures (superior, 24.0% versus 4.8%; P=0.002; and posterior, 32.0% versus 4.2%; P<0.001). Device migration occurred in 4 adults (2 cases each of surgical and transcatheter retrieval); in the 21 remaining failures, the device was unreleased and withdrawn. After a median follow-up of 10.0 years (2.5-17 years), all patients were alive with no history of late complications. CONCLUSIONS: Closure of large atrial septal defects using the Amplatzer device is safe and effective in both adults and children. Superior and posterior rim deficiencies are associated with procedural failure. Closure can be performed under transthoracic echocardiographic guidance in experienced centers. Early device migration is rare and can be safely managed by device extraction. Long-term follow-up showed no deaths or major late complications in our population of 311 patients.

Mitral disease: the real burden for Ross-Konno procedure in children.

BACKGROUND: Aortic valve replacement and management of complex left ventricular outflow tract obstruction in early life remains a surgical challenge. We assessed our experience with the Ross-Konno procedure. METHODS: Since 2000, 49 consecutive patients (24 neonates and infants) underwent the Ross-Konno procedure. Anatomic and clinical risk factors were analyzed. RESULTS: Median age was 12.2 months (0.0 to 194.4); 82% had previous valvotomy (surgical, n = 26; balloon, n = 7; balloon then surgical, n = 7) and 35% preceding arch repair (n = 17). Fifteen patients (31%) required concomitant procedures: mitral valve repair (n = 11), replacement (n = 1), endocardial fibroelastosis resection (n = 4), and aortic arch repair (n = 2). There were 5 hospital deaths (10.2%). Median follow-up was 63 ± 47 months. There were 4 late deaths (8.1%), all because of persistent pulmonary hypertension despite subsequent mitral procedures. Five-year actuarial survival and freedom from reoperation were 79.7% ± 6.1% and 68.6% ± 9.3%, respectively. Preoperative lower shortening fraction (p = 0.005) was associated with early mortality, while concomitant mitral surgery and pulmonary hypertension (p = 0.002) were associated with late mortality. Sixteen patients underwent 26 reoperations. Autograft function was normal in 30 of the 37 late survivors (81.1%), 4 (10.8%) had grade 2 regurgitation, and 3 (8.1%) required valve replacement. CONCLUSIONS: Ross-Konno in children remains a high-risk procedure. Preoperative ventricular dysfunction is associated with significant early mortality and should favor conservative options. Mitral involvement substantially affects late outcome, survival for these patients relies on the efficacy in relieving mitral disease. Efforts to improve mitral repair in these infants are critically required as an alternative to univentricular pathways.

All-age relationship between arm span and height in different ethnic groups.

The objective of the present study was to establish multiethnic, all-age prediction equations for estimating stature from arm span in males and females. The arm span/height ratio (ASHR) from 13 947 subjects (40.9% females), aged 5-99 years, from nine centres (in China, Europe, Ghana, India and Iran) was used to predict ASHR as a function of age using the lambda, mu and sigma method. Z-scores for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC in 1503 patients were calculated using measured height and height calculated from arm span and age. ASHR varied nonlinearly with age, was higher in males than in females and differed significantly between the nine sites. The data clustered into four groups: Asia, Europe, Ghana and Iran. Average predicted FEV1, FVC and FEV1/FVC using measured or predicted height did not differ, with standard deviations of 4.6% for FEV1, 5.0% for FVC and 0.3% for FEV1/FVC. The percentages of disparate findings for a low FEV1, FVC and FEV1/FVC in patients, calculated using measured or predicted height, were 4.2%, 3.2% and 0.4%, respectively; for a restrictive pattern, there were 1.0% disparate findings. Group- and sex-specific equations for estimating height from arm span and age to derive predicted values for spirometry are clinically useful.

Reoperations for left atrioventricular valve dysfunction after repair of atrioventricular septal defect.

OBJECTIVES: Postoperative left atrioventricular valve (LAVV) dysfunction is known to be the principal risk factor influencing outcome after repair of all types of atrioventricular septal defect (AVSD). The purpose of the present study was to identify the risk factors for reoperation and to assess the outcomes after reoperation for LAVV dysfunction. METHODS: Records of 412 patients who underwent anatomical repair for different types of AVSD from January 2000 to July 2012 were reviewed. The study group (n = 60) included 13 additional patients for whom repair ± LAVV reoperation was performed in a primary institution. Outcomes, independent risk factors, reoperation and death were analysed. RESULTS: There were 7 early, (1.7%) and 1 late death. Forty-seven (11.4%) required 64 reoperations for LAVV dysfunction. The median delay for the first LAVV reoperation was 3.5 months (range: 5 days to 10.0 years). Unbalanced ventricles with small left ventricle [odds ratio (OR) = 4.06, 95% confidence interval (CI): 1.58-10.44, P = 0.004], double-orifice LAVV (OR = 5.04, 95% CI: 1.39-18.27, P = 0.014), prior palliative surgery (OR = 3.5, 95% CI: 1.14-10.8, P = 0.029) and discharge echocardiography documenting LAVV regurgitation grade >2 (OR = 21.96, 95% CI: 8.91-54.09, P < 0.001) were found to be independent risk factors for LAVV reoperation. Twelve-year survival and freedom from LAVV reoperation rates were, respectively, 96.1% (95% CI: 94.1-98.1) and 85.8% (95% CI: 81.3-90.3). Survival was significantly worse in patients who underwent LAVV reoperation (P < 0.001) and in those who underwent valve replacement vs valve repair (P = 0.020). CONCLUSION: After AVSD repair, LAVV dysfunction appears to be the principal factor that influences outcome. It can usually be managed by repair. Need for multiple reoperations is not uncommon. Long-term outcome in patients with repaired LAVV is favourable.

Right ventricular plasticity in a porcine model of chronic pressure overload.

BACKGROUND: Ventricular-arterial coupling is a measure of the relationship between ventricular contractility and afterload. We sought to determine the relationship between ventricular-arterial coupling and right ventricular (RV) remodeling in a novel porcine model of progressive pulmonary hypertension (PH). METHODS: Chronic PH was induced in pigs by ligation of the left pulmonary artery (PA) followed by 5 weekly injections of cyanoacrylate to progressively obstruct the right lower lobe arteries (PH group, n = 10). At 6 weeks, 5 PH animals underwent reperfusion of the left lung through conduit anastomosis to decrease RV afterload, whereas 5 other animals received no treatment. Five sham-operated piglets were used as controls. RV function was assessed using echocardiography and conductance catheterization. RV gene expression of beta-myosin heavy chain (ß-MHC) and B-type natriuretic peptide (BNP) were quantified by polymerase chain reaction. RESULTS: At 6 weeks, compared with controls, the PH group had higher mean PA pressure (32 ± 6 vs 14 ± 2 mm Hg, p < 0.01). The increase in RV elastance was insufficient to compensate for the increase in pulmonary arterial elastance in the PH group and altered ventricular-arterial coupling occurred (0.65 ± 0.16 vs 1.28 ± 0.14, p < 0.01). The degree of ventricular-arterial uncoupling was related to RV enlargement and systolic dysfunction. Ventricular-arterial uncoupling and increased RV mass index were associated with up-regulation of ß-MHC and BNP expression. CONCLUSIONS: Ventricular-arterial coupling is closely associated with ventricular remodeling and systolic function as well as contractile and BNP gene expression. Dynamic changes in myosin expression may determine RV work efficiency in PH.

The pattern of the coronary arterial orifices in hearts with congenital malformations of the outflow tracts: a marker of rotation of the outflow tract during cardiac development?

Outflow tract defects, including cardiac neural crest defects (so-called conotruncal defects) and transposition of the great arteries, are due to an abnormal rotation of the outflow tract during cardiac development. Coronary orifices are often abnormal in outflow tract defects, particularly in common arterial trunk (CAT). A recent study indicates that abnormal coronary artery pattern in a mouse model with common arterial outlet (Tbx1-/- mouse mutant) could be due to a reduced and malpositioned subpulmonary coronary-refractory myocardial domain. The aim of our study was to demonstrate the relation between coronary orifices pattern in outflow tract defects in human and the abnormal embryonic rotation of the outflow tract. We analyzed 101 heart specimens with outflow tract defects: 46 CAT, 15 tetralogy of Fallot (TOF), 29 TOF with pulmonary atresia (TOF-PA), 11 double-outlet right ventricle with subaortic ventricular septal defect (DORV) and 17 controls. The position of left and right coronary orifices (LCO, RCO) was measured in degrees on the aortic/truncal circumference. The anterior angle between LCO and RCO (α) was calculated. The LCO was more posterior in TOF (31 °), TOF-PA (47 °), DORV (44 °), CAT (63 °), compared with controls (0 °, P < 0.05), and more posterior in CAT than in other outflow tract defects (P < 0.05). The RCO was more anterior in TOF (242 °), TOF-PA (245 °) and DORV (271 °) than in controls (213 °, P < 0.05), but not in CAT (195 °). The α angle was similar in TOF, TOF-PA, DORV and controls (149 °, 162 °, 133 °, 147 °), but significantly larger in CAT (229 °, P < 0.0001). In all outflow tract defects but CAT, the displacement of LCO (anterior) and RCO (posterior), while the α angle remains constant, might be due to incomplete rotation of the myocardium at the base of the outflow tract, leading to an abnormally positioned subpulmonary coronary-refractory myocardial domain. The larger α angle in CAT could reflect its dual identity, aortic and pulmonary.

Electrical velocimetry as a tool for measuring cardiac output in small infants after heart surgery.

PURPOSE: Cardiac output (CO), the product of stroke volume (SV) and heart rate, is essential to guarantee organ perfusion, especially in the intensive care setting. As invasive measurement of CO bears the risk of complications there is a need for non-invasive alternatives. We investigated if electrical velocimetry (EV) and transthoracic Doppler (Doppler-TTE) are interchangeable for the non-invasive measurement of SV and able to reflect the post-surgical SV/CO trend. METHODS: Comparison of SV measurements by EV and Doppler-TTE was performed in 24 newborns after switch operation (n = 240 measurements). Three subgroups of measurements (=periods) were created according to the patients' status in the course of post-surgical CO recovery. RESULTS: Bland-Altman analysis found acceptable bias and limits of agreement for the interchangeability of the two methods. Mean overall SV was 3.7 ml with a mean overall bias of 0.28 ml (=7.6 %). The mean percentage error of 29 % was acceptable according to the method of Critchley and Critchley. Overall precision expressed by the coefficient of variation (CV) was 6.6 % for SV(TTE) and 4.4 % for SV(EV). SV(TTE) and SV(EV) medians in the three periods were significantly different and documented the post-surgical CO trend. CONCLUSIONS: EV and Doppler-TTE are interchangeable for estimating SV. EV has the advantages of easy handling and allows continuous measurement.

Continuous cerebral perfusion for aortic arch repair: hypothermia versus normothermia.

BACKGROUND: Deep hypothermia with circulatory arrest (CA) is routinely used for aortic arch repair. Antegrade selective cerebral perfusion (ASCP) has been proposed to avoid neurologic complications. The optimal temperature during aortic arch repair with ASCP is not well established. We therefore compared early outcomes of patients undergoing aortic arch repair associated with intracardiac repair with ASCP either with hypothermia (<28°C, group I; n=70) or normothermia (>34°C, group II; n=40). METHODS: From 2002 to 2008, 110 consecutive patients with interrupted aortic arch (n=40) or coarctation of the aorta (n=70) and cardiac anomalies underwent intracardiac and aortic arch repair without CA. Median age at repair was 12 days. Full cardiopulmonary bypass (CPB), high hematocrit, and high rates of flow were used. ASCP flow was adjusted to maintain arterial pressure at greater than or equal to 50 mm Hg. ASCP was achieved either through a Gore-Tex (W. L. Gore & Associates, Inc., Elkton, MD) graft to the innominate artery (n=36) or by direct cannulation (n=74). An electroencephalogram (EEG) was continuously monitored and 30 patients were monitored by near-infrared spectroscopy (NIRS). RESULTS: Preoperative data were similar in both groups. Group II demonstrated higher ASCP flows (p<0.001). Time to extubation, stay in the intensive care unit (ICU), and postoperative urine output and lactate levels were similar between groups. Mortality was 8.5% in group I versus 10% in group II. During the postoperative course, there were no clinical or electrical neurologic events in either group. CONCLUSIONS: Antegrade selective cerebral perfusion can safely avoid CA. No worse, early, or long-term effects of ASCP with normothermia were found.

Coronary aorto-ostial stenosis analysed by multislice computed tomography: a new tool for percutaneous coronary intervention?

AIMS: Conventional quantitative coronary angiography approaches are limited to quantify complex aorto-ostial stenosis. Multislice CT was able to detect and classify coronary plaques, compared with intravascular ultrasound (IVUS). The aim of the present study was to determine the accuracy of multislice computed tomography (CT) in addition to conventional angiography to identify aorto-ostial coronary stenosis characteristics before revascularisation. METHODS AND RESULTS: Patients with coronary ostial stenosis were selected for the study. All patients had selective coronary angiography and retrospectively ECG-gated multislice CT (Siemens AG, Munich, Germany). IVUS was performed in patients with ambiguous ostial stenosis revealed by angiography. Forty significant aorto-ostial lesions (38 patients) were analysed by two independent observers in comparison with an expert consensus blinded or not to the coronary CT data sets. Using CT in addition to angiography permitted observers to obtain a strong agreement for assessment of calcified lesions (kappa value 0.75), a good agreement for aortic plaques location and ideal stent position in aorto-ostial coronary stenosis. CONCLUSIONS: This study shows that CT associated with an angiogram allows a better identification of aorto-ostial plaques morphology and ideal stent position in aorto-ostial coronary stenosis before angioplasty.