In the 70＇s, we classified for the first time the blocks at the atrial level into interatrial blocks （IAB）, partial and advanced, and other types of atrial blocks including the concept of atrial aberrancy, and atri...In the 70＇s, we classified for the first time the blocks at the atrial level into interatrial blocks （IAB）, partial and advanced, and other types of atrial blocks including the concept of atrial aberrancy, and atrial dissociation.展开更多
The high prevalence of interatrial block （IAB） is widely neglected due to its frequent underdiaguosis. Its prevalence depends mainly on age and also on the presence of associ- ated heart disease. In patients without...The high prevalence of interatrial block （IAB） is widely neglected due to its frequent underdiaguosis. Its prevalence depends mainly on age and also on the presence of associ- ated heart disease. In patients without structural heart dis- ease, it is mainly an elderly condition. This is particularly true for advanced IAB, rarely found in global population before 65 years but with prevalence of 8% in the 70＇s and 25% in centenarians,tll When studying prevalence data of this condition, three factors should be taken into account in order to interpret differences that are frequently related with the methodology used （Table 1, Figure 1）.展开更多
It was not until 1979 that Bayes de Ltma described atrial conduction blocks and classified them as interatrial and intra- atrial.Interatrial blocks refer to conduction disorders lo- cated between the atria, while intr...It was not until 1979 that Bayes de Ltma described atrial conduction blocks and classified them as interatrial and intra- atrial.Interatrial blocks refer to conduction disorders lo- cated between the atria, while intraalxial blocks occur within the same atrium. This work motivated several authors, in- cluding Bayes himself, to further investigate atrial conduc- tion and interatrial block （IAB）.展开更多
Background:Left atrial appendage closure(LAAC)with simultaneous interventional occlusion therapy for congenital interatrial communication has become a new focus of patients with nonvalvular atrial fibrillation.Little ...Background:Left atrial appendage closure(LAAC)with simultaneous interventional occlusion therapy for congenital interatrial communication has become a new focus of patients with nonvalvular atrial fibrillation.Little is known about the results of mid-and long-term results.Objective:The aim of this study was to evaluate the midand long-term safety and effectiveness of simultaneous transcatheter closure of the left atrial appendage(LAA)and congenital interatrial communication closure in atrial fibrillation(AF)patients.Methods:From Jan 2016 to June 2017,27 patients with AF were treated with simultaneous transcatheter closure of the LAA and atrial septal defect(ASD,n=22),patent foramen ovale(PFO,n=5).Results:The perioperative closure success rate was 96.3%,except for cardiac tamponade occurred in one ASD patient.During the median 37.6-month follow-up period,no cases of cerebrovascular or peripheral vascular embolism,bleeding,infective endocarditis or thrombosis along the occluders were observed.Of the 21 patients with NYHA Class III,nineteen had significant improvements to NYHA Classes I or II,and 81.5%of patients were free from major or minor adverse events during midand long-term follow-up.Conclusions:Simultaneous closure of the LAA and congenital interatrial communication closure is a viable option for patients with nonvalvular atrial fibrillation who are at risk of stroke or systemic embolism,and it is effective and yields excellent mid-and long-term results.展开更多
BACKGROUND Heart failure(HF),especially in patients with preserved ejection fraction and midrange ejection fraction,remains a significant global health burden.Interatrial shunt devices(IASDs),which allow blood flow fr...BACKGROUND Heart failure(HF),especially in patients with preserved ejection fraction and midrange ejection fraction,remains a significant global health burden.Interatrial shunt devices(IASDs),which allow blood flow from the left to the right atrium,offer a novel treatment approach by reducing left atrial pressure and alleviating symptoms.AIM To evaluate the efficacy and safety of IASDs in patients with HF through a systematic review and meta-analysis.METHODS We performed a systematic review and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines,analyzing studies up to April 2025.Randomized controlled trials and observational studies comparing interatrial shunt therapy with control groups were included.Data on clinical outcomes were analyzed using Review Manager software.RESULTS Nine studies involving 1689 patients were included.IASDs significantly improved cardiac output[mean difference(MD):0.72,95%CI:0.13-1.32,P=0.02],right atrial pressure(RAP)(MD:0.70,95%CI:0.14-1.26,P=0.01),and 6-minute walk distance(MD:71.63,95%CI:24.13-119.13,P=0.003).There were no significant differences in major adverse cardiac events,myocardial infarction,ischemic stroke,or new-onset atrial fibrillation.However,all-cause mortality[risk ratio(RR):1.49,95%CI:1.02-2.18,P=0.04]and cardiovascular death(RR:1.66,95%CI:1.01-2.74,P=0.05)were significantly higher in the shunt group.CONCLUSION IASDs offer significant short-term improvements in cardiac output,RAP,and exercise capacity in HF patients.However,long-term safety concerns,particularly regarding mortality,necessitate further research and careful patient selection.展开更多
Massive calcification of left atrium is an uncommon complication of long-standing rheumatic valvular disease, and is most often observed in patients with a previous operation on mitral valve. Most patients have experi...Massive calcification of left atrium is an uncommon complication of long-standing rheumatic valvular disease, and is most often observed in patients with a previous operation on mitral valve. Most patients have experienced symptoms for more than 15 years. Massive calcification of the left atrium generality spared the interatrial septum in the previous studies. However, to our knowledge, fewer than five cases have presented as full left atrial calcification （Table）.展开更多
AIM:To investigate long-term efficacy of two different devices more than five years after percutaneous atrial septal defect(ASD)closure in adults.METHODS:All patients who underwent percutaneous closure of an ASD in th...AIM:To investigate long-term efficacy of two different devices more than five years after percutaneous atrial septal defect(ASD)closure in adults.METHODS:All patients who underwent percutaneous closure of an ASD in the St.Antonius Hospital,Nieuwegein,The Netherlands,between February 1998 and December 2006 were included.Percutaneous closure took place under general anaesthesia and transesophageal echocardiographic moni toring.Transthoracic echocardiography(TTE)was performed 24 h post-procedure to visualize the device position and to look for residual shunting using color Doppler.All complications were registered.All patients were invited for an outpatient visit and contrast TTE more than 5-years after closure.Efficacy was based on the presence of a residual right-to-left shunt(RLS),graded as minimal,moderate or severe.The presence of a residual left-to-right shunt(LRS)was diagnosed using color Doppler,and was not graded.Descriptive statistics were used for patients'characteristics.Univariate analysis was used to identify predictors for residual shunting.RESULTS:In total,104 patients(mean age 45.5±17.1 years)underwent percutaneous ASD closure using an Amplatzer device(ASO)in 76 patients and a Cardioseal/Starflex device(CS/SF)in 28 patients.The mean follow-up was 6.4±3.4 years.Device migration occurred in 4 patients of whom two cases occurred during the index hospitalization(1 ASO,1 CS/SF).The other 2 cases of device migration occurred during the first 6 mo of follow-up(2 CS/SF).The recurrent thrombo-embolic event rate was similar in both groups:0.4%per follow-up year.More than 12 mo post-ASD closure and latest follow-up,new-onset supraventricular tachyarrhythmia's occurred in 3.9%and 0%for the ASO and CS/SF group,respectively.The RLS rate at latest follow-up was 17.4%(minimal 10.9%,moderate 2.2%,severe 4.3%)and 45.5%(minimal 27.3%,moderate 18.2%,severe 0%)for the ASO-and CS/SF groups,respectively.There was no residual LRS in both groups.CONCLUSION:Percutaneous ASD closure has good long-term safety and efficacy profiles.The residual RLS rate seems to be high more than 5 years after closure,especially in the CS/SF.Residual LRS was not observed.展开更多
Atrial fibrillation （AF） is the most frequent arrhythmia. Due to population aging, AF is a growing epidemic and its importance will continue to increase in the next decades. Although the prevalence of AF is high in ...Atrial fibrillation （AF） is the most frequent arrhythmia. Due to population aging, AF is a growing epidemic and its importance will continue to increase in the next decades. Although the prevalence of AF is high in advanced age, the number of subjects with predisposing factors for AF is even higher. Most of these factors increase the risk of atrial fibro- sis, an important component of atrial arrhythmia mecha- nisms. In fact, the new techniques to detect atrial fibrosis are showing the strong association between atrial fibrosis and AF risk. Regarding predisposing factors for AF, interatrial block （LAB） seems to be a key factor.展开更多
Recent studies have suggested that patients with high CHA2DS2VASc-score [Congestive Heart failure, hyperten- sion, Age ≥ 75 years （doubled）, Diabetes, Stroke （doubled）, Vascular disease, Age 65-74 years, Sex cate...Recent studies have suggested that patients with high CHA2DS2VASc-score [Congestive Heart failure, hyperten- sion, Age ≥ 75 years （doubled）, Diabetes, Stroke （doubled）, Vascular disease, Age 65-74 years, Sex category （female sex）] thromboembolic complications occurred irrespective of the presence of atrial fibrillation （AF） and anticoagulant therapy may be initiated irrespective of documented AF.展开更多
BACKGROUND Cardiac lipoma and lipomatous hypertrophy of interatrial septum(LHIS)are very rare disorders with distinct pathological features.While cardiac lipoma is a well-circumscribed encapsulated tumor of mature adi...BACKGROUND Cardiac lipoma and lipomatous hypertrophy of interatrial septum(LHIS)are very rare disorders with distinct pathological features.While cardiac lipoma is a well-circumscribed encapsulated tumor of mature adipocytes,LHIS is due to entrapment of fat cells in the interatrial septum during embryogenesis.Although a biopsy is the definitive diagnostic test,these disorders can be differentiated by a cardiac magnetic resonance imaging(MRI).Treatment of LHIS is not warranted in asymptomatic patients.In symptomatic patients,surgical resection is the only recommended treatment,which has shown to improve good long-term prognosis.CASE SUMMARY A 63-year-old Caucasian woman with past medical history significant for hypertension,hypothyroidism,right breast ductal cell carcinoma treated with mastectomy and breast implant,platelet granule disorder,asthma requiring chronic intermittent prednisone use,presented to the outpatient cardiology office with recent onset exertional dyspnea,palpitations,weight gain and weakness.Initial workup with electrocardiogram and holter monitor did not reveal significant findings.During the subsequent hospitalization for community acquired pneumonia,the patient developed symptomatic paroxysmal atrial fibrillation.Transthoracic echocardiogram showed a right ventricular mass.A biopsy was not pursued given the high risk of bleeding due to platelet granule disorder.Cardiac MRI showed characteristic features consistent with cardiac lipoma and LHIS.Prednisone was discontinued.Genetic testing for arrhythmogenic right ventricular dysplasia and 24-h urine cortisol test was negative.As multiple attempts at rhythm control failed with sotalol and flecainide,pulmonary vein isolation and right atrial isthmus radiofrequency ablation were done.She is in follow-up with symptomatic relief and no recurrence of atrial fibrillation for 10 mo.CONCLUSION Benign fatty lesions in heart include solitary lipoma,lipomatous infiltration and lipomatous hypertrophy of interatrial septum.Although transvenous biopsy provides a definitive diagnosis,Cardiac MRI is superior to computed tomography and aids in differentiating benign from malignant lesions.Surgical excision of cardiac lipoma along with capsule and pedicle removal generally prevents recurrence,but with our patient’s unusual tumor features and comorbidities proscribed a surgical approach.Symptom management with antiarrhythmics and ablation techniques were successfully utilized.展开更多
A 69-year-old man was admitted to our center to undergo catheter ablation of paroxysmal atrial fibrillation refractory to antiarrhythmic drug therapy. This procedure required access to the left atrium through the inte...A 69-year-old man was admitted to our center to undergo catheter ablation of paroxysmal atrial fibrillation refractory to antiarrhythmic drug therapy. This procedure required access to the left atrium through the interatrial septum. During hospitalization, the patient performed routinely pre-procedure transthoracic echocardiography and gadolinium-enhanced cardiac magnetic resonance showing a normal anatomy of both the fossa ovalis and the interatrial septum. Access to the left atrium proved difficult and several unsuccessful attempts to perform the trans-septal puncture were made under both fluoroscopy and intracardiac echocardiography guidance, even with radiofrequency energy delivery. Finally, trans-septal puncture was successfully carried out using a novel nitinol J-shaped "Safe Sept" trans-septal guidewire, designed to cross the interatrial septum through the trans-septal needle thanks to a special sharp tip. Moreover, thanks to its rounded J shape that reduces the risk of atrial perforation, the "Safe Sept" guidewire, when advanced into the left atrium, becomes atraumatic.展开更多
[Objectives] This study was conducted to better understand the characteristics of the fetal blood circulation. [Methods] The cardiac opening of the inferior vena cava was observed in goat fetuses. There are two cardia...[Objectives] This study was conducted to better understand the characteristics of the fetal blood circulation. [Methods] The cardiac opening of the inferior vena cava was observed in goat fetuses. There are two cardiac openings of the inferior vena cava, namely, the foramen ovale with the valves and the right atrium opening of the inferior vena cava. The blood from the inferior vena cava moves easily into the right atrium via the right atrium opening because the right atrium opening without the valves is located in the lower right of the foramen ovale, and is bigger than the interatrial foramen. [Results] The blood may flow into the left atrium through the foramen ovale when the blood volume into the right atrium exceeds the limit of the right atrium. The fetal inferior vena cava compared with after birth receives oxygenated blood in the umbilical vein from the placenta besides the normal blood. Accordingly the blood volume into the right atrium exceeds the limit of the right atrium. Extra oxygenated blood is diverted directly into the left atrium through the foramen ovale. [Conclusions] This study provides a reference for studying the blood circulation of fetuses and even adults.展开更多
文摘In the 70＇s, we classified for the first time the blocks at the atrial level into interatrial blocks （IAB）, partial and advanced, and other types of atrial blocks including the concept of atrial aberrancy, and atrial dissociation.
文摘The high prevalence of interatrial block （IAB） is widely neglected due to its frequent underdiaguosis. Its prevalence depends mainly on age and also on the presence of associ- ated heart disease. In patients without structural heart dis- ease, it is mainly an elderly condition. This is particularly true for advanced IAB, rarely found in global population before 65 years but with prevalence of 8% in the 70＇s and 25% in centenarians,tll When studying prevalence data of this condition, three factors should be taken into account in order to interpret differences that are frequently related with the methodology used （Table 1, Figure 1）.
文摘It was not until 1979 that Bayes de Ltma described atrial conduction blocks and classified them as interatrial and intra- atrial.Interatrial blocks refer to conduction disorders lo- cated between the atria, while intraalxial blocks occur within the same atrium. This work motivated several authors, in- cluding Bayes himself, to further investigate atrial conduc- tion and interatrial block （IAB）.
基金This study was supported by grants from National Natural Science Foundation of China(81870367)Doctoral Start-up Foundation of Liaoning Province of China(2019-BS-266).
文摘Background:Left atrial appendage closure(LAAC)with simultaneous interventional occlusion therapy for congenital interatrial communication has become a new focus of patients with nonvalvular atrial fibrillation.Little is known about the results of mid-and long-term results.Objective:The aim of this study was to evaluate the midand long-term safety and effectiveness of simultaneous transcatheter closure of the left atrial appendage(LAA)and congenital interatrial communication closure in atrial fibrillation(AF)patients.Methods:From Jan 2016 to June 2017,27 patients with AF were treated with simultaneous transcatheter closure of the LAA and atrial septal defect(ASD,n=22),patent foramen ovale(PFO,n=5).Results:The perioperative closure success rate was 96.3%,except for cardiac tamponade occurred in one ASD patient.During the median 37.6-month follow-up period,no cases of cerebrovascular or peripheral vascular embolism,bleeding,infective endocarditis or thrombosis along the occluders were observed.Of the 21 patients with NYHA Class III,nineteen had significant improvements to NYHA Classes I or II,and 81.5%of patients were free from major or minor adverse events during midand long-term follow-up.Conclusions:Simultaneous closure of the LAA and congenital interatrial communication closure is a viable option for patients with nonvalvular atrial fibrillation who are at risk of stroke or systemic embolism,and it is effective and yields excellent mid-and long-term results.
文摘BACKGROUND Heart failure(HF),especially in patients with preserved ejection fraction and midrange ejection fraction,remains a significant global health burden.Interatrial shunt devices(IASDs),which allow blood flow from the left to the right atrium,offer a novel treatment approach by reducing left atrial pressure and alleviating symptoms.AIM To evaluate the efficacy and safety of IASDs in patients with HF through a systematic review and meta-analysis.METHODS We performed a systematic review and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines,analyzing studies up to April 2025.Randomized controlled trials and observational studies comparing interatrial shunt therapy with control groups were included.Data on clinical outcomes were analyzed using Review Manager software.RESULTS Nine studies involving 1689 patients were included.IASDs significantly improved cardiac output[mean difference(MD):0.72,95%CI:0.13-1.32,P=0.02],right atrial pressure(RAP)(MD:0.70,95%CI:0.14-1.26,P=0.01),and 6-minute walk distance(MD:71.63,95%CI:24.13-119.13,P=0.003).There were no significant differences in major adverse cardiac events,myocardial infarction,ischemic stroke,or new-onset atrial fibrillation.However,all-cause mortality[risk ratio(RR):1.49,95%CI:1.02-2.18,P=0.04]and cardiovascular death(RR:1.66,95%CI:1.01-2.74,P=0.05)were significantly higher in the shunt group.CONCLUSION IASDs offer significant short-term improvements in cardiac output,RAP,and exercise capacity in HF patients.However,long-term safety concerns,particularly regarding mortality,necessitate further research and careful patient selection.
文摘Massive calcification of left atrium is an uncommon complication of long-standing rheumatic valvular disease, and is most often observed in patients with a previous operation on mitral valve. Most patients have experienced symptoms for more than 15 years. Massive calcification of the left atrium generality spared the interatrial septum in the previous studies. However, to our knowledge, fewer than five cases have presented as full left atrial calcification （Table）.
文摘AIM:To investigate long-term efficacy of two different devices more than five years after percutaneous atrial septal defect(ASD)closure in adults.METHODS:All patients who underwent percutaneous closure of an ASD in the St.Antonius Hospital,Nieuwegein,The Netherlands,between February 1998 and December 2006 were included.Percutaneous closure took place under general anaesthesia and transesophageal echocardiographic moni toring.Transthoracic echocardiography(TTE)was performed 24 h post-procedure to visualize the device position and to look for residual shunting using color Doppler.All complications were registered.All patients were invited for an outpatient visit and contrast TTE more than 5-years after closure.Efficacy was based on the presence of a residual right-to-left shunt(RLS),graded as minimal,moderate or severe.The presence of a residual left-to-right shunt(LRS)was diagnosed using color Doppler,and was not graded.Descriptive statistics were used for patients'characteristics.Univariate analysis was used to identify predictors for residual shunting.RESULTS:In total,104 patients(mean age 45.5±17.1 years)underwent percutaneous ASD closure using an Amplatzer device(ASO)in 76 patients and a Cardioseal/Starflex device(CS/SF)in 28 patients.The mean follow-up was 6.4±3.4 years.Device migration occurred in 4 patients of whom two cases occurred during the index hospitalization(1 ASO,1 CS/SF).The other 2 cases of device migration occurred during the first 6 mo of follow-up(2 CS/SF).The recurrent thrombo-embolic event rate was similar in both groups:0.4%per follow-up year.More than 12 mo post-ASD closure and latest follow-up,new-onset supraventricular tachyarrhythmia's occurred in 3.9%and 0%for the ASO and CS/SF group,respectively.The RLS rate at latest follow-up was 17.4%(minimal 10.9%,moderate 2.2%,severe 4.3%)and 45.5%(minimal 27.3%,moderate 18.2%,severe 0%)for the ASO-and CS/SF groups,respectively.There was no residual LRS in both groups.CONCLUSION:Percutaneous ASD closure has good long-term safety and efficacy profiles.The residual RLS rate seems to be high more than 5 years after closure,especially in the CS/SF.Residual LRS was not observed.
文摘Atrial fibrillation （AF） is the most frequent arrhythmia. Due to population aging, AF is a growing epidemic and its importance will continue to increase in the next decades. Although the prevalence of AF is high in advanced age, the number of subjects with predisposing factors for AF is even higher. Most of these factors increase the risk of atrial fibro- sis, an important component of atrial arrhythmia mecha- nisms. In fact, the new techniques to detect atrial fibrosis are showing the strong association between atrial fibrosis and AF risk. Regarding predisposing factors for AF, interatrial block （LAB） seems to be a key factor.
文摘Recent studies have suggested that patients with high CHA2DS2VASc-score [Congestive Heart failure, hyperten- sion, Age ≥ 75 years （doubled）, Diabetes, Stroke （doubled）, Vascular disease, Age 65-74 years, Sex category （female sex）] thromboembolic complications occurred irrespective of the presence of atrial fibrillation （AF） and anticoagulant therapy may be initiated irrespective of documented AF.
文摘BACKGROUND Cardiac lipoma and lipomatous hypertrophy of interatrial septum(LHIS)are very rare disorders with distinct pathological features.While cardiac lipoma is a well-circumscribed encapsulated tumor of mature adipocytes,LHIS is due to entrapment of fat cells in the interatrial septum during embryogenesis.Although a biopsy is the definitive diagnostic test,these disorders can be differentiated by a cardiac magnetic resonance imaging(MRI).Treatment of LHIS is not warranted in asymptomatic patients.In symptomatic patients,surgical resection is the only recommended treatment,which has shown to improve good long-term prognosis.CASE SUMMARY A 63-year-old Caucasian woman with past medical history significant for hypertension,hypothyroidism,right breast ductal cell carcinoma treated with mastectomy and breast implant,platelet granule disorder,asthma requiring chronic intermittent prednisone use,presented to the outpatient cardiology office with recent onset exertional dyspnea,palpitations,weight gain and weakness.Initial workup with electrocardiogram and holter monitor did not reveal significant findings.During the subsequent hospitalization for community acquired pneumonia,the patient developed symptomatic paroxysmal atrial fibrillation.Transthoracic echocardiogram showed a right ventricular mass.A biopsy was not pursued given the high risk of bleeding due to platelet granule disorder.Cardiac MRI showed characteristic features consistent with cardiac lipoma and LHIS.Prednisone was discontinued.Genetic testing for arrhythmogenic right ventricular dysplasia and 24-h urine cortisol test was negative.As multiple attempts at rhythm control failed with sotalol and flecainide,pulmonary vein isolation and right atrial isthmus radiofrequency ablation were done.She is in follow-up with symptomatic relief and no recurrence of atrial fibrillation for 10 mo.CONCLUSION Benign fatty lesions in heart include solitary lipoma,lipomatous infiltration and lipomatous hypertrophy of interatrial septum.Although transvenous biopsy provides a definitive diagnosis,Cardiac MRI is superior to computed tomography and aids in differentiating benign from malignant lesions.Surgical excision of cardiac lipoma along with capsule and pedicle removal generally prevents recurrence,but with our patient’s unusual tumor features and comorbidities proscribed a surgical approach.Symptom management with antiarrhythmics and ablation techniques were successfully utilized.
文摘A 69-year-old man was admitted to our center to undergo catheter ablation of paroxysmal atrial fibrillation refractory to antiarrhythmic drug therapy. This procedure required access to the left atrium through the interatrial septum. During hospitalization, the patient performed routinely pre-procedure transthoracic echocardiography and gadolinium-enhanced cardiac magnetic resonance showing a normal anatomy of both the fossa ovalis and the interatrial septum. Access to the left atrium proved difficult and several unsuccessful attempts to perform the trans-septal puncture were made under both fluoroscopy and intracardiac echocardiography guidance, even with radiofrequency energy delivery. Finally, trans-septal puncture was successfully carried out using a novel nitinol J-shaped "Safe Sept" trans-septal guidewire, designed to cross the interatrial septum through the trans-septal needle thanks to a special sharp tip. Moreover, thanks to its rounded J shape that reduces the risk of atrial perforation, the "Safe Sept" guidewire, when advanced into the left atrium, becomes atraumatic.
基金Supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Scientific Research Fund of Nanjing General Hospital of Nanjing Military Command,China(2016033)
文摘[Objectives] This study was conducted to better understand the characteristics of the fetal blood circulation. [Methods] The cardiac opening of the inferior vena cava was observed in goat fetuses. There are two cardiac openings of the inferior vena cava, namely, the foramen ovale with the valves and the right atrium opening of the inferior vena cava. The blood from the inferior vena cava moves easily into the right atrium via the right atrium opening because the right atrium opening without the valves is located in the lower right of the foramen ovale, and is bigger than the interatrial foramen. [Results] The blood may flow into the left atrium through the foramen ovale when the blood volume into the right atrium exceeds the limit of the right atrium. The fetal inferior vena cava compared with after birth receives oxygenated blood in the umbilical vein from the placenta besides the normal blood. Accordingly the blood volume into the right atrium exceeds the limit of the right atrium. Extra oxygenated blood is diverted directly into the left atrium through the foramen ovale. [Conclusions] This study provides a reference for studying the blood circulation of fetuses and even adults.
