Unguarded Tricuspid Valve and Pulmonary Atresia With Intact Ventricular Septum Complicated With Right Coronary Artery Fistula and Advanced Atrioventricular Block in a Fetus: A Case Report.

The unguarded tricuspid valve is a rare and severe condition. When found in the fetus, they mostly undergo abortion or intrauterine death. The details of the fetal course in such cases are poorly understood. Here, we report a case of an unguarded tricuspid valve detected at 20 weeks of gestation who developed a complete atrioventricular block and survived in utero. The fetus also had pulmonary atresia with intact ventricular septum, Uhl's disease, hypoplastic right ventricle, noncompacted left ventricle, valvular aortic stenosis, and right coronary artery fistula to the right ventricle. Despite this serious condition, the fetal hydrops did not develop. The baby was born at 33 weeks of gestation but died on day two. Our experience suggests that some babies may survive the fetal period even with the severe type of an unguarded tricuspid valve. Hence, efficient fetal and neonatal treatment strategies for fetal unguarded tricuspid valves are crucial.

Progression of left ventricular apical hypoplasia-like restrictive cardiomyopathy with severe pulmonary hypertension: Follow-up from fetal stage.

Left ventricular (LV) apical hypoplasia is a rare restrictive cardiomyopathy subtype with an unclear pathophysiology. LV apical hypoplasia typically presents with elongated right ventricle (RV) wrapping around a truncated and spherical LV with a deficient apex (the "banana-shape" of the RV). Here we report a case of a young boy with apparent LV apical hypoplasia that developed after birth; no "banana-shaped" RV was observed during the fetal period. Moreover, suprasystemic pulmonary hypertension (PH) developed even after a mitral valve replacement was performed for progressive mitral stenosis and regurgitation at 14 months of age. He underwent surgery for the Potts shunt, a shunt between the pulmonary artery and aorta, at 13 years to secure systemic output. His PH ameliorated and his heart failure remained stable for 3 years after the operation. This case indicates that the "banana-shaped" RV seen in this condition is not always congenital but that it can form and develop after birth. Furthermore, this case supports the usefulness of the Potts shunt as a therapeutic option in patients with severe PH due to LV apical hypoplasia. .

Antenatal Therapy for Fetal Supraventricular Tachyarrhythmias: Multicenter Trial.

BACKGROUND: Standardized treatment of fetal tachyarrhythmia has not been established. OBJECTIVES: This study sought to evaluate the safety and efficacy of protocol-defined transplacental treatment for fetal supraventricular tachycardia (SVT) and atrial flutter (AFL). METHODS: In this multicenter, single-arm trial, protocol-defined transplacental treatment using digoxin, sotalol, and flecainide was performed for singleton pregnancies from 22 to <37 weeks of gestation with sustained fetal SVT or AFL ≥180 beats/min. The primary endpoint was resolution of fetal tachyarrhythmia. Secondary endpoints were fetal death, pre-term birth, and neonatal arrhythmia. Adverse events (AEs) were also assessed. RESULTS: A total of 50 patients were enrolled at 15 institutions in Japan from 2010 to 2017; short ventriculoatrial (VA) SVT (n = 17), long VA SVT (n = 4), and AFL (n = 29). One patient with AFL was excluded because of withdrawal of consent. Fetal tachyarrhythmia resolved in 89.8% (44 of 49) of cases overall and in 75.0% (3 of 4) of cases of fetal hydrops. Pre-term births occurred in 20.4% (10 of 49) of patients. Maternal AEs were observed in 78.0% (39 of 50) of patients. Serious AEs occurred in 1 mother and 4 fetuses, thus resulting in discontinuation of protocol treatment in 4 patients. Two fetal deaths occurred, mainly caused by heart failure. Neonatal tachyarrhythmia was observed in 31.9% (15 of 47) of neonates within 2 weeks after birth. CONCLUSIONS: Protocol-defined transplacental treatment for fetal SVT and AFL was effective and tolerable in 90% of patients. However, it should be kept in mind that serious AEs may take place in fetuses and that tachyarrhythmias may recur within the first 2 weeks after birth.

Fenestration in the Fontan circulation as a strategy for chronic cardioprotection.

BACKGROUND: Fenestration in the Fontan circulation potentially liberates patients from factors leading to cardiovascular remodelling, through stable haemodynamics with attenuated venous congestion. We hypothesised that a fenestrated Fontan procedure would possess chronic haemodynamic advantages beyond the preload preservation. METHODS: We enrolled 35 patients with fenestrated Fontan with a constructed pressure-volume relationship under dobutamine (DOB) infusion and/or transient fenestration occlusion (TFO). Despite the use of antiplatelets and anticoagulants, natural closure of fenestration was confirmed in 11 patients. Cardiovascular properties in patients with patent fenestration (P-F) were compared with those in patients with naturally closed fenestration (NC-F). To further delineate the roles of fenestration, paired analysis in patients with P-F was performed under DOB or rapid atrial pacing with/without TFO. RESULTS: As compared with P-F, patients with NC-F had a higher heart rate (HR), smaller ventricular end-diastolic area, better ejection fraction and higher central venous pressure, with higher pulmonary resistance. While this was similarly observed after DOB infusion, DOB markedly augmented diastolic and systolic ventricular stiffness in patients with NC-F compared with patients with P-F. As a mirror image of the relationship between patients with P-F and NC-F, TFO markedly reduced preload, suppressed cardiac output, and augmented afterload and diastolic stiffness. Importantly, rapid atrial pacing compromised these haemodynamic advantages of fenestration. CONCLUSIONS: As compared with patients with NC-F, patients with P-F had robust haemodynamics with secured preload reserve, reduced afterload and a suppressed beta-adrenergic response, along with a lower HR at baseline, although these advantages had been overshadowed, or worsened, by an increased HR.

M-mode Diagnosis of Tachyarrhythmia Can be Erroneous Owing to "Pseudo 1:1 Atrioventricular Movement" of the Atrial Wall Adjacent to the Atrioventricular Valve Possibly due to Atrioventricular Constraint: A Case of Neonatal Atrial Flutter With 2:1 Atrioventricular Conduction.

M-mode echocardiography has been playing an important role in the diagnosis of fetal tachyarrhythmia. We recently encountered a neonatal case of atrial flutter with 2:1 atrioventricular conduction. However, M-mode erroneously indicated 1:1 atrioventricular movement. While the movement of the atrial wall far from the atrioventricular valve was much faster than that of the ventricular wall, the atrial wall adjacent to the atrioventricular valve fully synchronized to that of the ventricular wall. Thus, to avoid this novel pitfall, it would be important to add an additional assessment focusing on the movement of the atrial wall far from the ventricle.

The impact of intrauterine treatment on fetal tachycardia: a nationwide survey in Japan.

OBJECTIVES: To investigate the clinical course of fetal tachycardia and analyze the impact of intrauterine treatment on the postnatal treatment and patient outcomes. STUDY DESIGN: This was a retrospective review of cases of fetal tachycardia that occurred from 2004 to 2006. Data were collected from questionnaires that were sent to all 750 secondary or tertiary perinatal care centers in Japan. RESULTS: Eighty-two cases (14 with fetal hydrops) were analyzed (supraventricular tachycardia [SVT], n = 52; atrial flutter [AFL], n = 23; and ventricular tachycardia, n = 7). The overall mortality was 3.7%. Intrauterine treatment was performed for 41 fetuses (50.0%). Digoxin, flecainide and sotalol were mainly used for SVT and AFL. Fetal tachycardia resolved in 90.0% (27/30) of the cases without fetal hydrops and 90.9% (10/11) of the cases with fetal hydrops. Intrauterine treatment significantly reduced the incidence of cesarean delivery (29.3 vs. 70.7%, p < .01), preterm birth (12.2 vs. 41.5%, p = .02) and neonatal arrhythmias (48.8 vs. 78.0%, p = .01) in comparison to untreated fetuses. CONCLUSIONS: This nationwide survey revealed that intrauterine treatment was performed for approximately half of the cases of fetal tachycardia and was associated with lower rates of cesarean delivery, premature birth and neonatal arrhythmias in comparison to untreated fetuses.

Low risk of treatment resistance in Down syndrome with Kawasaki disease.

BACKGROUND: A Japanese nationwide survey has reported that Down syndrome (DS) is a less-frequently occurring comorbidity in Kawasaki disease (KD). Although altered immune responses are frequently observed in DS, no studies have focused on the treatment response and risk for coronary artery abnormalities (CAA) in DS patients with KD. The aim of this study was therefore to evaluate the clinical manifestations, treatment response and prevalence of CAA in DS with KD. METHODS: We retrospectively reviewed the medical records of DS patients with KD from 2005 through 2012. The survey questionnaires were sent to facilities nationwide, and clinical data regarding KD in DS were collected. A control group consisted of non-DS patients with KD who were managed at Toho University. RESULTS: Of the 94 233 children diagnosed with acute KD from 2005 to 2012, 16 children with acute KD also had DS (0.017%). The DS-KD patients were significantly older than the non-DS patients (median, 8 years vs 1 year, P < 0.05, respectively). Half of the DS patients had incomplete KD. Although 50% of the DS children were at high risk of immunoglobulin resistance, all children responded to initial treatment and none had CAA. CONCLUSIONS: All DS-KD patients responded to initial i.v. immunoglobulin (IVIG) or aspirin despite having a high risk of IVIG resistance, and none of the DS patients had CAA. This suggests that the risk of treatment resistance and development of CAA may be not higher in DS patients with acute KD.

Antenatal antiarrhythmic treatment for fetal tachyarrhythmias: a study protocol for a prospective multicentre trial.

INTRODUCTION: Several retrospective or single-centre studies demonstrated the efficacy of transplacental treatment of fetal tachyarrhythmias. Our retrospective nationwide survey showed that the fetal therapy will be successful at an overall rate of 90%. For fetuses with hydrops, the treatment success rate will be 80%. However, standard protocol has not been established. The objective of this study is to evaluate the efficacy and safety of the protocol-defined transplacental treatment of fetal tachyarrhythmias. Participant recruitment began in October 2010. METHODS AND ANALYSIS: The current study is a multicentre, single-arm interventional study. A total of 50 fetuses will be enrolled from 15 Japanese institutions. The protocol-defined transplacental treatment is performed for singletons with sustained fetal tachyarrhythmia ≥180 bpm, with a diagnosis of supraventricular tachycardia or atrial flutter. Digoxin, sotalol, flecainide or a combination is used for transplacental treatment. The primary endpoint is disappearance of fetal tachyarrhythmias. The secondary endpoints are fetal death related to tachyarrhythmia, proportion of preterm birth, rate of caesarean section attributable to fetal arrhythmia, improvement in fetal hydrops, neonatal arrhythmia, neonatal central nervous system disorders and neonatal survival. Maternal, fetal and neonatal adverse events are evaluated at 1 month after birth. Growth and development are also evaluated at 18 and 36 months of corrected age. ETHICS AND DISSEMINATION: The Institutional Review Board of the National Cerebral and Cardiovascular Center of Japan has approved this study. Our findings will be widely disseminated through conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: UMIN Clinical Trials Registry UMIN000004270.

Serial sonographic findings during progression from acute pyelonephritis to renal abscess: a rare case report.

Renal abscess, accumulation of infective fluid in the kidney, is a rare pathology. Currently, no reports of the serial imaging changes of acute pyelonephritis (APN) progressing to renal abscess exist. We report clinical and serial sonographic findings of a patient with hyper-immunoglobulin E syndrome, a primary immunodeficiency, who developed APN that progressed to renal abscess. Renal ultrasonography revealed that echogenicity of infectious lesions dramatically changed from isoechoic to hyperechoic and to hypoechoic during progression. These findings are useful for differential diagnosis of APN, acute focal bacterial nephritis, and renal abscess.

Developmental Changes in Aortic Mechanical Properties in Normal Fetuses and Fetuses with Cardiovascular Disease.

BACKGROUND: We hypothesized that fetal aortic mechanical properties assessed by aortic diameter (AoD) and flow show maturational changes during the gestational period, and that these properties are different in fetuses with congenital heart diseases and fetuses with normal development. METHODS: Phasic changes in ascending AoD along with Doppler flow profile were measured in 84 consecutive normal fetuses (gestational age, 18-36 weeks) and in 30 consecutive fetuses with cardiovascular diseases (gestational age, 22-39 weeks). RESULTS: AoD and cardiac output significantly increased with gestational age. Fetal aortic compliance (AC), assessed as (maximum AoD - minimum AoD)/stroke volume, significantly decreased with gestational age in normal fetuses, indicating maturational changes in aortic wall properties. Importantly, fetuses with Marfan syndrome and tetralogy of Fallot that exhibit "aortopathy" showed significantly lower AC than normal fetuses of the same gestational age, suggesting intrinsic abnormalities in aortic wall properties in these diseases. Fetuses with trisomy 18 and Noonan syndrome also had AC values below the normal ranges. CONCLUSION: Measurements of phasic changes in fetal AoD and flow measurements can provide useful information about aortic mechanical properties and may help clarify abnormal arterial hemodynamics in pathologic conditions.

Fetal bradyarrhythmia associated with congenital heart defects - nationwide survey in Japan.

BACKGROUND: Because there is limited information on fetal bradyarrhythmia associated with congenital heart defects (CHD), we investigated its prognosis and risk factors. METHODS AND RESULTS: In our previous nationwide survey of fetal bradyarrhythmia from 2002 to 2008, 38 fetuses had associated CHD. Detailed clinical data were collected from secondary questionnaires on 29 fetuses from 18 institutions, and were analyzed. The 29 fetuses included 22 with isomerism, 4 with corrected transposition of the great arteries (TGA) and 3 with critical pulmonary stenosis; 14 had complete atrioventricular block (AVB), 8 had second-degree AVB, and 16 had sick sinus syndrome; 5 died before birth, and 10 died after birth (5 in the neonatal period). Neonatal and overall survival rates for fetal bradyarrhythmia with CHD were 66% and 48%, respectively. Pacemaker implantation was needed in 17 cases (89%). Beta-sympathomimetics were administered in utero in 13 cases and were effective in 6, but were not associated with prognosis. All cases of corrected TGA or ventricular rate ≥70 beats/min survived. A ventricular rate <55 beats/min had significant effects on fetal myocardial dysfunction (P=0.02) and fetal hydrops (P=0.04), resulting in high mortality. CONCLUSIONS: The prognosis of fetal bradyarrhythmia with CHD is still poor. The type of CHD, fetal myocardial dysfunction, and fetal hydrops were associated with a poor prognosis, depending on the ventricular rate.

Usefulness of cystatin C in the postoperative management of pediatric patients with congenital heart disease.

BACKGROUND: The characteristics of the renal marker cystatin C (Cys-C) in association with the postoperative management of children with congenital heart disease (CHD) remain unclear. METHODS AND RESULTS: Serum Cys-C and creatinine (Cr) levels were measured preoperatively and on the third postoperative day in 53 consecutive CHD patients (age, 1 day-11 years). On the third postoperative day, the patients were divided into 2 groups: the clinically severe group, requiring continuous infusion of diuretic drugs or peritoneal dialysis; and the non-severe group, composed of those without such needs. Preoperative Cys-C level decreased with age (by month) during the first year of life and remained almost constant thereafter, while Cr level increased with age. The Cys-C ratio (Cys-C level on the third postoperative day/preoperative level) was positively correlated with Cr ratio (R=0.57, P<0.001). Both Cys-C and Cr levels increased in correlation with the clinical severity of renal impairment. Receiver operating characteristic curve analysis failed to demonstrate an advantage of Cys-C over Cr in detecting severity. CONCLUSIONS: Cys-C may be a useful marker of renal function in terms of hemodynamic status in the postoperative management of CHD, although its superiority over Cr could not be confirmed. Future studies should clarify the role of Cys-C in clinical decision-making and evaluate the relationship of Cys-C with factors that may affect its levels.

Stent Implantation for Effective Treatment of Refractory Chylothorax due to Superior Vena Cava Obstruction as a Complication of Congenital Cardiac Surgery.

Chylothorax is a serious complication of congenital cardiac surgery and is significantly associated with increased morbidity and mortality. Central venous obstruction, which is often related to the insertion of central venous catheters for postoperative management, is known to be an important risk factor for treatment failure and mortality associated with this condition. We present the case of a 6-month-old girl with refractory chylothorax after surgical repair of tetralogy of Fallot. The chylous drainage continued for more than 2 months despite maximal conservative therapy (water restriction, total parenteral nutrition, and infusion of somatostatin and steroid) and surgical ligation of the thoracic duct. Subsequently, we observed stenosis of the superior vena cava (SVC) caused by large thrombi possibly associated with the prolonged use of central venous catheter placed in the internal jugular vein. Because transcatheter balloon dilation failed to relieve the stenosis, we performed stent implantation for the SVC and innominate vein. After the procedure, chylous drainage dramatically reduced, and the patient was discharged from the hospital. In conclusion, central venous obstruction due to thrombosis should be routinely examined when chylothorax is diagnosed and is resistant to conservative therapy after congenital heart surgery. Stent implantation can effectively relieve the venous obstruction and thus be a life-saving treatment option for this difficult condition.

Effects of age on hemodynamic changes after transcatheter closure of atrial septal defect: importance of ventricular diastolic function.

Some older patients develop symptoms of clinical heart failure after closure of an atrial septal defect (ASD). The present study tested the hypothesis that baseline hemodynamics and hemodynamic changes induced by transcatheter ASD closure are different between younger and older patients due to age-related differences in left ventricular (LV) diastolic dysfunction. Forty-three consecutive patients (27.7 ± 16.3 years of age, range 5-63, median 25) who underwent device closure for ASD were divided into younger (age ≤25, n = 24, 15.1 ± 1.2 years) and older (> 25 years, n = 19, 43.7 ± 2.2 years) groups. Echocardiographic evaluations were performed 1 day before and 2 days after ASD closure. Before ASD repair, early diastolic mitral annular velocity (e') on lateral, an index of ventricular relaxation, showed an age-related decrease. After closure, e' decreased by similar amount in both groups (p < 0.05). In addition, E/e', an index of LV filling pressure, was relatively unchanged in the younger group (from 5.4 to 5.9) but significantly increased (p < 0.05) in the older group (from 6.3 to 8.1) over similar increase of normalized LV diastolic dimension. In older patients, ASD closure resulted in further deterioration of baseline impairment in LV relaxation and the increased LV stiffness caused a more marked rise in LV filling pressure, compared to the younger group. Thus, ASD should be closed at a younger age before the development of age-related LV diastolic dysfunction.

Evaluation of transplacental treatment for fetal congenital bradyarrhythmia: ­ nationwide survey in Japan ­.

BACKGROUND: There are few large studies of fetal congenital bradyarrhythmia. The aim of the present study was to investigate the effects and risks of transplacental treatment for this condition. METHODS AND RESULTS: Using questionnaires, 128 cases of fetal bradyarrhythmia were identified at 52 Japanese institutions from 2002 to 2008. Of the 128 fetuses, 90 had structurally normal hearts. Among these 90 fetuses, 61 had complete atrioventricular block (CAVB), 16 had second-degree AVB, 8 had sinus bradycardia, and 5 had other conditions. The 61 CAVB fetuses were divided into those who did (n = 38) and those who did not (n = 23) receive transplacental medication. Monotherapy with ß-sympathomimetics, steroid monotherapy, and combination therapy with these agents was given in 11, 5 and 22 cases, respectively. Beta-sympathomimetics improved bradycardia (P<0.001), but no medication could significantly improve the survival rate. Fetal hydrops was associated with a 14-fold increased risk of perinatal death (P = 0.001), and myocardial dysfunction was a significant risk factor for poor prognosis (P = 0.034). Many adverse effects were observed with steroid treatment, with fetal growth restriction increasing significantly after >10 weeks on steroids (P = 0.043). CONCLUSIONS: Treatment with ß-sympathomimetics improved bradycardia, but survival rate did not differ significantly in fetuses with and without transplacental medication. It is recommended that steroid use should be limited to <10 weeks to avoid maternal and fetal adverse effects, especially fetal growth restriction and oligohydramnios.

Late clinical manifestations of mitral valve disease and severe pulmonary hypertension in a patient diagnosed with premature closure of foramen ovale during fetal life.

BACKGROUND: The patency of foramen ovale (FO) in fetal circulation is very important, and premature closure of FO could be associated with several pathological conditions. METHODS: We report a patient in whom premature closure of FO in fetal life was associated with late clinical onset of mitral valve stenosis and subsequent development of irreversible pulmonary hypertension (PH). RESULTS: The patient showed persistent PH after birth, which completely regressed at the age of 8 months. However, the patient developed heart failure due to mitral valve lesions (hammock valve) at the age of 11 months and underwent artificial valve replacement. The patient subsequently developed severe PH, which was refractory to anti-PH therapy with sildenafil and bosentan in addition to home oxygen. CONCLUSIONS: This case illustrates that mitral stenosis can be overlooked during early neonatal life, and thus emphasizes the need for close follow-up for potential existence of mitral stenosis and later clinical manifestation in patients with premature FO closure even when initial careful examination of the mitral valves does not indicate any abnormalities. In addition, premature closure of FO could cause pulmonary vascular disease, which may lead to later development of irreversible PH.

Usefulness of early diastolic mitral annular velocity to predict plasma levels of brain natriuretic peptide and transient heart failure development after device closure of atrial septal defect.

Device closure of atrial septal defect (ASD) is sometimes followed by elevation of plasma brain natriuretic peptide (BNP), a marker of heart failure, and progression to heart failure. This study tested the hypothesis that the underlying diastolic dysfunction, assessed on tissue Doppler images (TDI) before device closure, can predict BNP level after ASD closure. The study subjects were 39 consecutive patients (age 27.5 +/- 16.3 years, range 5 to 63) who underwent device closure for ASD. Echocardiographic evaluation using TDI and 2-dimensional and pulse wave Doppler were performed, together with plasma BNP measurement 1 day before and 2 days after ASD closure. Before ASD closure, an age-dependent decrease was noted in left ventricular relaxation, assessed by early diastolic mitral annular velocity. ASD closure resulted in a decrease in early diastolic mitral annular velocity (from 14.7 to 12.3 cm/s, p <0.05) despite an increase in the left ventricular dimension (84% to 92% vs normal, p <0.05). These changes were associated with a parallel increase in BNP (17.9 to 48.4 pg/ml, p <0.05). Stepwise multivariate linear regression identified early diastolic mitral annular velocity before ASD closure and age as independent predictors of BNP levels after ASD closure (p <0.05). Consistent with this result, 2 patients with the lowest early diastolic mitral annular velocity developed exertional dyspnea after the procedure. In conclusion, our results indicate that TDI measurements could be useful to detect underlying diastolic dysfunction that can potentially cause heart failure after ASD closure and emphasize the importance of ASD closure at a young age before impairment of left ventricular relaxation.

Successful management of the persistent pulmonary hypertension of the newborn with transposition of the great arteries by restricted patency of the ductus arteriosus: a simple and rational novel strategy.

Persistent pulmonary hypertension of the newborn (PPHN) complicated with transposition of the great arteries (TGA) and an intact ventricular septum (IVS) often is therapy resistant and associated with an extremely poor prognosis. For this condition, opening of the ductus arteriosus (DA) by prostaglandin-E1 in conjunction with balloon atrial septostomy and nitric oxide inhalation therapy has been applied as an initial treatment strategy. A case of PPHN with TGA/IVS is presented together with a strategy of intentionally restricted DA to increase pulmonary blood flow successfully used in treating PPHN that otherwise was resistant to conventional therapy. The DA restriction strategy may help to improve the prognosis of patients who have PPHN complicated with TGA/IVS.

Ventricular-vascular stiffening in patients with repaired coarctation of aorta: integrated pathophysiology of hypertension.

BACKGROUND: Despite successful repair, patients with coarctation of the aorta (COA) often show persistent hypertension at rest and/or during exercise. Previous studies indicated that the hypertension is mainly due to abnormalities in the arterial bed and its regulatory systems. We hypothesized that ventricular systolic stiffness also contributes to the hypertensive state in these patients in addition to increased vascular stiffness. METHODS AND RESULTS: The study involved 43 patients with successfully repaired COA and 45 age-matched control subjects. Ventricular systolic stiffness (end systolic elastance) and arterial stiffness (effective arterial elastance) were measured invasively by ventricular pressure-area relationship during varying preload before and after beta-adrenergic stimulation. The mean systolic blood pressure was significantly higher with concomitant increases in both end systolic elastance and effective arterial elastance in patients with COA compared with control subjects (113.2+/-16.8 versus 91.0+/-9.1 mm Hg, 44.5+/-17.0 versus 19.2+/-6.7 mm Hg/mL/m(2), and 27.8+/-11.4 versus 20.2+/-4.8 mm Hg/mL/m(2), respectively; P<0.01 for each). End systolic elastance and effective arterial elastance of patients with COA showed exaggerated responses to beta-adrenergic stimulation, further amplifying blood pressure elevation. Quantification analyses assuming that ventricular systolic stiffness of patients with COA is equal to that of the control revealed that ventricular systolic stiffness accounts for approximately 50% to 70% of the elevated blood pressure in patients with COA. Furthermore, combined ventricular-arterial stiffening amplified systolic pressure sensitivity to increased preload during abdominal compression and limited stroke volume gain/relaxation improvement induced by beta-adrenergic stimulation. CONCLUSIONS: Increased ventricular systolic stiffness, coupled with increased arterial stiffness, plays important roles in hypertension in patients with repaired COA. Thus, ventricular systolic stiffness is a potentially suitable target for reduction of blood pressure and improvement of prognosis of patients with COA.