改良Nikaidoh 手术治疗合并肺动脉瓣狭窄的右室双出口

目的:总结改良Nikaidoh手术治疗右心室双出口(DORV)患者的临床经验,以提高手术疗效。方法:2例先天性心脏病右心室双出口伴肺动脉瓣狭窄行改良Nikaidoh手术,游离主动脉根部及冠状动脉,重建左心室流出道,以带单瓣牛心包片补片重建肺动脉及右心室流出道。结果:术后患者紫绀消失,复查心脏彩超仅有轻度肺动脉瓣关闭不全,未发现左、右心室流出道梗阻,康复出院。结论:采用改良Nikaidoh手术治疗伴肺动脉瓣狭窄的右室双出口,术后可获得良好的血流动力学效果,早期临床结果满意。     

Hypertrophic cardiomyopathy associated with left ventricular aneurysm and normal coronary arteries: Case study indicating genetic tendencies of cardiomyopathy

A 50-year-old man presented with hypertrophic obstructive cardiomyopathy (HOC) associated with a left ventricular aneurysm and normal coronary arteries. His history revealed no evidence of myocardial infarction or atypical angina. Physical examination disclosed HOC but did not suggest the presence of an aneurysm. Although the patient was treated medically, heart failure ensued, and he died suddenly while working his farm. Subsequent investigation of the patient's family revealed that three of his five children were also affected by cardiomyopathy, which was especially pronounced in the eldest, a 22-year-old man. The possible hemodynamic relationship between HOC and left ventricular aneurysm is discussed, along with probable indications. The role of left ventricular aneurysm is also presented in relation to the natural history of the disease.     

改良Nikaidoh手术治疗合并肺动脉瓣狭窄的右室双出口

目的：总结改良Nikaidoh手术治疗右心室双出口（DORV）患者的临床经验,以提高手术疗效。方法：2例先天性心脏病右心室双出口伴肺动脉瓣狭窄行改良Nikaidoh手术,游离主动脉根部及冠状动脉,重建左心室流出道,以带单瓣牛心包片补片重建肺动脉及右心室流出道。结果：术后患者紫绀消失,复查心脏彩超仅有轻度肺动脉瓣关闭不全,未发现左、右心室流出道梗阻,康复出院。结论：采用改良Nikaidoh手术治疗伴肺动脉瓣狭窄的右室双出口,术后可获得良好的血流动力学效果,早期临床结果满意。     

Muscular Subaortic Stenosis: The Effect of Peripheral Vasodilatation

Amyl nitrite was administered on two occasions to a patient with muscular subaortic stenosis, to ascertain if selective peripheral vasodilatation would affect the degree of obstruction to left ventricular outflow in this condition. On each occasion there was a marked increase in the systolic pressure gradient across the left ventricular outflow tract prior to the onset of reflex tachycardia. Following the second amyl nitrite inhalation, the systolic cross-sectional area of the left ventricular outflow tract decreased to 1.0 sq. cm., from the control value of 2.6 sq. cm. It is believed that the increased degree of muscular subaortic stenosis, following peripheral vasodilatation, could be secondary to a decrease in the systolic size of the whole left ventricle, or to a selective decrease in the physical size of the left ventricular outflow tract.     

In vitro hemodynamic investigation of the embryonic aortic arch at late gestation

This study focuses on the dynamic flow through the fetal aortic arch driven by the concurrent action of right and left ventricles. We created a parametric pulsatile computational fluid dynamics (CFD) model of the fetal aortic junction with physiologic vessel geometries. To gain a better biophysical understanding, an in vitro experimental fetal flow loop for flow visualization was constructed for identical CFD conditions. CFD and in vitro experimental results were comparable. Swirling flow during the acceleration phase of the cardiac cycle and unidirectional flow following mid-deceleration phase were observed in pulmonary arteries (PA), head-neck vessels, and descending aorta. Right-to-left (oxygenated) blood flowed through the ductus arteriosus (DA) posterior relative to the antegrade left ventricular outflow tract (LVOT) stream and resembled jet flow. LVOT and right ventricular outflow tract flow mixing had not completed until approximately 3.5 descending aorta diameters downstream of the DA insertion into the aortic arch. Normal arch model flow patterns were then compared to flow patterns of four common congenital heart malformations that include aortic arch anomalies. Weak oscillatory reversing flow through the DA junction was observed only for the Tetralogy of Fallot configuration. PA and hypoplastic left heart syndrome configurations demonstrated complex, abnormal flow patterns in the PAs and head-neck vessels. Aortic coarctation resulted in large-scale recirculating flow in the aortic arch proximal to the DA. Intravascular flow patterns spatially correlated with abnormal vascular structures consistent with the paradigm that abnormal intravascular flow patterns associated with congenital heart disease influence vascular growth and function.     

Extended fetal echocardiographic examination for detecting cardiac malformations in low risk pregnancies.

OBJECTIVE--To improve the rate of prenatal detection of cardiac malformations in a low risk population. DESIGN--Comparison of extended fetal echocardiography with the standard four chamber view in detecting abnormalities. Extended echocardiography comprised the four chamber view and visualisation of the left ventricular outflow tract, the right ventricular outflow tract, and the main pulmonary artery and its branches. In cases with abnormal results complete echocardiographic studies were performed by a paediatric cardiologist using M mode, Doppler, and colour flow mapping techniques. SETTING--Obstetric ultrasonographic unit at Shaare-Zedek Medical Centre, Jerusalem. SUBJECTS--5400 fetuses in low risk pregnancies between 18 and 24 weeks'' gestation (mean 21 weeks); 53 were lost to follow up. MAIN OUTCOME MEASURES--Detection of abnormality before and after birth. RESULTS--During the study 23 infants (0.4%) were born with cardiac abnormalities, 21 of whom had major structural and functional heart disease. 18 fetuses had heart disease diagnosed prenatally, 11 by the four chamber view alone (sensitivity 48%) and a further seven by extended echocardiography (sensitivity 78%). Five fetal cardiac defects were missed prenatally (false negative rate 22%). These included coarctation of aorta, persistent truncus arteriosus, tetralogy of Fallot, ventricular septal defect, and pulmonic stenosis. Only one false positive diagnosis (coarctation of aorta) was made (specificity 99.9%, false positive rate 0.1%). The abnormality was correctly identified in 17 out of 18 cases. CONCLUSIONS--The extended fetal heart examination detected 86% (18/21) of major abnormalities in a low risk population. The examination should be incorporated into routine prenatal ultrasonographic investigations.     

Varix of the heart causing outflow tract obstruction.

We report a case about a neonate who died of severe subaortic stenosis due to a giant vascular dilation of the left ventricular outflow tract. We emphasize the fatal result of this benign lesion and make differential diagnosis with haemangiomas and valvular blood cysts.     

DiGeorge syndrome presenting as severe congenital heart disease in the newborn.

In seven infants with DiGeorge syndrome the major clinical manifestation was cardiac failure in the 1st week of life. All had severe congenital heart disease: five had interruption of the aortic arch and associated lesions, one had a ventricular septal defect and a cervical aorta, and one had truncus arteriosus. All but one died by 2 weeks of age. Necropsy data lent support to the hypothesis of a relation between the cardiovascular anomalies and defective development of structures derived from the third and fourth pharyngeal pouches.     

产前B 超诊断胎儿完全性大动脉转位的超声特征观察

目的:探讨产前B超对胎儿完全性大动脉转位的临床诊断价值。方法:回顾性分析2012年2月至2015年11月我院收治的4例胎儿完全性大动脉转位的B超特征,并对比病理结果。结果:4例完全性大动脉转位胎儿中,1例室间隔缺损,3例四腔心切面正常。左右两室流出道切面情况:4例胎儿大动脉与心室连接关系存在异常,2例胎儿室间隔膜部存在缺损症状。三血管气管切面情况:4例胎儿均仅可见2条血管。结论:对左右两心室流出道切面及三血管气管切面进行观察可得,胎儿完全性大动脉转位具有较为明显的B超特征,产前对胎儿完全性大动脉转位进行B超诊断具有较好的临床价值,建议在医疗单位推广应用。     

Muscular Subaortic Stenosis: The Initial Left Ventricular Inflow Tract Pressure as Evidence of Outflow Tract Obstruction

Two types of intraventricular pressure differences within the left ventricle of man are described. The first is encountered in cases of muscular (or fibrous) subaortic stenosis, in which the outflow tract pressure distal to the stenosis (and proximal to the aortic valve) is low, whereas all pressures recorded in the left ventricle proximal to the stenosis, including that just inside the mitral valve (the initial inflow tract pressure) are high.The second type of intraventricular pressure difference may be recorded in patients without muscular subaortic stenosis when a heart catheter is advanced to the left ventricular wall in such a manner that it becomes imbedded or entrapped by cardiac muscle in systole. Such an entrapped catheter records a high intraventricular pressure that is believed to reflect intramyocardial tissue pressure, which normally exceeds intracavitary pressure. In such cases the initial inflow tract pressure is not high and is precisely equal to the outflow tract systolic pressure, i.e. both are recording intracavity pressure. This type of intramyocardial to intracavitary pressure difference may also be encountered in the left ventricle of dogs.The recent suggestion that intraventricular pressure differences in the left ventricle of cases of muscular subaortic stenosis are due to catheter entrapment by cardiac muscle is refuted by using the initial inflow tract pressure as the means of differentiation between the two types of intraventricular pressure differences outlined.     

Insights from in-vitro flow visualization into the mechanism of systolic anterior motion of the mitral valve in hypertrophic cardiomyopathy under steady flow conditions.

Hypertrophic obstructive cardiomyopathy is a heart disease characterized by a thickened interventricular septum which narrows the left ventricular outflow tract, and by systolic anterior motion (SAM) of the mitral valve which can contact the septum and create dynamic subaortic obstruction. The most common explanation for SAM has been the Venturi mechanism which postulates that septal hypertrophy, by narrowing the outflow tract, produces high velocities and thus low pressure between the mitral valve and the septum, causing the valve leaflets to move anteriorly. This hypothesis, however, fails to explain why SAM often begins early in systole, when outflow tract velocities are low or negligible or why it may occur in the absence of septal hypertrophy. The goal of this study was therefore to investigate an alternative hypothesis in which structural abnormalities of the papillary muscles act as a primary cause of SAM by altering valve restraint and thereby changing the geometry of the closed mitral apparatus and its relationship to the surrounding flow field. In order to test this hypothesis, an in vitro model of the left ventricle which included an explanted human mitral valve with intact chords and papillary muscle apparatus was constructed. Flow visualization was used to observe the ventricular flow field and the mitral valve geometry. Displacing the papillary muscles anteriorly and closer to each other, as observed clinically in patients with cardiomyopathy and obstruction produced SAM in the absence of septal hypertrophy. Flow could be seen impacting on the upstream (posterior) surface of the leaflets; such flow is capable of producing form drag forces which can initiate and maintain SAM.(ABSTRACT TRUNCATED AT 250 WORDS)     

A Canadian hospital's experience with the automatic implantable cardioverter/defibrillator.

The automatic implantable cardioverter/defibrillator is a device that can be implanted in patients for treatment of recurrent ventricular tachycardia and ventricular fibrillation. It was recently approved for clinical use in Canada. The authors describe their experience with 12 patients (mean age 51.3 years) who underwent implantation of a defibrillator. All 12 patients had a history of documented ventricular fibrillation, which was idiopathic in 3 and due to ischemic heart disease in 9. Electrophysiologic testing revealed inducible ventricular tachycardia or ventricular fibrillation in 8 of the 10 patients tested. An important criterion for selection for implantation was failure of pharmacologic therapy to suppress ventricular arrhythmias induced during electrophysiologic testing. Of the 12 patients, 1 died within 24 hours after implantation. During a mean follow-up period of 15.5 months there were no further deaths. All the surviving patients expressed satisfaction with the device; five of the seven under the age of 60 years have returned to work, and one has returned to school. This initial favourable experience with the automatic implantable cardioverter/defibrillator suggests that future increases in the availability of the device and improvements in its function will lead to much more widespread use, as the population of patients at risk of sudden cardiac death is large.     

Left Ventricular Wall Movement in Heart Failure

Of 34 patients admitted to hospital with left ventricular failure seven died before echocardiograms could be repeated after treatment and in three no echocardiograms could be obtained owing to chronic obstructive lung disease. In the remaining 24 patients echocardiograms were taken soon after admission and compared with echocardiograms taken later, after clinical improvement. The results show that in most patients both anterior and posterior motion of the posterior left ventricular wall increased. The rate of backward diastolic motion was appreciably less before and after treatment of heart failure compared with that in a small group of normal younger healthy men. This technique is a quick and apparently reliable way to assess ventricular function. The rate of diastolic motion is probably a reflection of left ventricular wall compliance.     

Conditional deletion of focal adhesion kinase leads to defects in ventricular septation and outflow tract alignment

To examine a role for focal adhesion kinase (FAK) in cardiac morphogenesis, we generated a line of mice with a conditional deletion of FAK in nkx2-5-expressing cells (herein termed FAKnk mice). FAKnk mice died shortly after birth, likely resulting from a profound subaortic ventricular septal defect and associated malalignment of the outflow tract. Additional less penetrant phenotypes included persistent truncus arteriosus and thickened valve leaflets. Thus, conditional inactivation of FAK in nkx2-5-expressing cells leads to the most common congenital heart defect that is also a subset of abnormalities associated with tetralogy of Fallot and the DiGeorge syndrome. No significant differences in proliferation or apoptosis between control and FAKnk hearts were observed. However, decreased myocardialization was observed for the conal ridges of the proximal outflow tract in FAKnk hearts. Interestingly, chemotaxis was significantly attenuated in isolated FAK-null cardiomyocytes in comparison to genetic controls, and these effects were concomitant with reduced tyrosine phosphorylation of Crk-associated substrate (CAS). Thus, it is possible that ventricular septation and appropriate outflow tract alignment is dependent, at least in part, upon FAK-dependent CAS activation and subsequent induction of polarized myocyte movement into the conal ridges. Future studies will be necessary to determine the precise contributions of the additional nkx2-5-derived lineages to the phenotypes observed.     

Unexpected sudden death due to recreational swimming and diving in men in Croatia in a 14-year period

The article deals with 17 sudden deaths which occurred during recreational swimming and diving in men in Croatia in a 14-year period: from January 1, 1998 to December 31, 2011. The sample is taken out from the total number of 61 sudden deaths in men during or immediately after sport or recreational exercise. Included are also sudden deaths of 8 foreigners spending holidays at the Croatian Adriatic Coast. In all of them forensic medicine autopsy was done. Thirteen males from Croatia died during recreational swimming. Three of them were aged 15-29 yrs: one had signs of hypertrophic cardiomyopathy, the second suffered from chronic myopericarditis with left ventricular aneurysm, and the third had cardiomegaly and blood alcohol level of 1.7 per thousand. Five were aged 30-64 yrs: four of them have suffered from coronary atherosclerosis and left ventricular hypertrophy of 15-18-18-22 mm, and one with left ventricular hypertrophy drowned suddenly, probably because of malignant ventricular arrhythmia. The fifth suffered stroke and drowned. Five elderly men, aged 65-85 yrs, have suffered from coronary atherosclerosis, myocardial fibrosis or myocardial scars, and three of them had left ventricular hypertrophy of 19 mm. Four males died during recreational diving. One aged 26yrs drowned, at autopsy he had left ventricular hypertrophy of 17 mm. Three males were middle-aged: two had coronary atherosclerosis, two of them had a severe degree of coronary atherosclerosis and one had coronary atherosclerosis of medium degree but with myocardial fibrosis and left ventricular hypertrophy of 18 mm. Seven male foreigners died, five of them during swimming: two aged 30-64 and two aged 65-85. They all have had coronary atherosclerosis: one of them had an acute myocardial infarction of the posterior wall, and one hypertrophic cardiomyopathy as well. One middle-aged and one elderly man died during diving, and both had an acute myocardial infarction of the posterior wall. One elderly foreign woman died during swimming, she had coronary atherosclerosis and a myocardial scar. In Croatia, death rate during both swimming and diving in men aged 15-29 years amounted to 0.63/1,000.000 (p=1.0000); in those aged 30-64 it reached 0.56/1,000.000 (p=0.3698), and in those aged 65-85 it was 1.41/1,000.000 (p=0.1849). The death rate during swimming in men aged 15-29 amounted to 1.47/1,000.000 (p=0.9864), in men aged 30-64 it reached 0.35/1,000.000 (p=0.2245), and in those aged 65-85 it was 1.41/1,000.000 (the difference is significant, p=0.0472). The death rate during diving in men aged 15-29 was 0.16/1,000.000, and in men aged 30-64 the observed rate was 0.21/1,000.000 (p=1.0000).     

Ventricle and outflow tract of the African lungfish Protopterus dolloi

We report a morphologic study of the heart ventricle and outflow tract of the African lungfish Protopterus dolloi. The ventricle is saccular and appears attached to the anterior pericardial wall by a thick tendon. An incomplete septum divides the ventricle into two chambers. Both the free ventricular wall and the incomplete ventricular septum are entirely trabeculated. Only a thin rim of myocardium separates the trabecular system from the subepicardial space. The outflow tract consists of proximal, middle, and distal portions, separated by two flexures, proximal and distal. The proximal outflow tract portion is endowed with a layer of compact, well-vascularized myocardium. This portion is homologous to the conus arteriosus observed in the heart of most vertebrates. The middle and distal outflow tract portions are arterial-like, thus being homologous to the bulbus arteriosus. However, the separation between the muscular and arterial portions of the outflow tract is not complete in the lungfish. A thin layer of myocardium covers the arterial tissue, and a thin layer of elastic tissue underlies the conus myocardium. Two unequal ridges composed of loose connective tissue, the spiral and bulbar folds, run the length of the outflow tract. They form an incomplete division of the outflow tract, but fuse at the distal end. The two folds are covered by endocardium and contain collagen, elastin, and fibroblast-like cells. They appear to be homologous to the dextro-dorsal and sinistro-ventral ridges observed during the development of the avian and mammalian heart. Two to three rows of vestigial arterial-like valves appear in the dorsal and ventral aspects of the conus. These valves are unlikely to have a functional role. The possible functional significance of the "gubernaculum cordis," the thick tendon extending between the anterior ventricular surface and the pericardium, is discussed.     

Sudden death during ambulatory monitoring.

Three patients with ischaemic heart disease died suddenly while being monitored with an ambulatory tape recorder. Two had terminal ventricular fibrillation initiated by paired bidirectional ventricular ectopic beats against a background of scattered ectopic activity; both had had ventricular tachycardia during routine treadmill exercise testing in the week before death. The third patient developed bizarre ventricular complexes followed by asystole. Sudden death may be due to ventricular fibrillation initiated by paired ventricular ectopic beats with changing morphology, or asystole following bizarre ventricular complexes. Exercise testing may have an important predictive value.     

Necrotizing enterocolitis in neonates with congenital heart disease

Both necrotizing enterocolitis (NEC) and congenital heart disease (CHD) are causes of significant morbidity and mortality in the neonatal population. While two distinct disease processes, NEC and CHD are inter-related as the incidence of NEC is greater in neonates with CHD than the normal newborn population. It is likely that circulatory perturbations, especially those seen in infants with left ventricular outflow tract lesions and single ventricle physiology, the stress of cardiac surgery and cardiopulmonary bypass, and the underlying baseline elevation of circulating endotoxin and proinflammatory cytokines all play a role in the pathogenesis of NEC in this uniquely susceptible population. The neurodevelopmental impairment in infants requiring surgery for NEC and in infants with complex congenital heart disease is alarming and requires further investigation. As medical and surgical advances allow for the palliation and correction of complex lesions at an earlier gestational age and lower birth weight, the already high risk of NEC in this population is likely to increase. This will require more aggressive study of the etiology of NEC in patients with CHD and the development of preventative therapies in order to decrease the impressive morbidity and mortality associated with the combination of these disease processes. In this article, we review the pathogenesis of NEC and CHD including associated mortality and morbidities and discuss possible mechanisms linking these two disease states.     

Expression of cardiac neural crest and heart genes isolated by modified differential display

The invasion of the cardiac neural crest (CNC) into the outflow tract (OFT) and subsequent outflow tract septation are critical events during vertebrate heart development. We have performed four modified differential display screens in the chick embryo to identify genes that may be involved in CNC, OFT, secondary heart field, and heart development. The screens included differential display of RNA isolated from three different axial segments containing premigratory cranial neural crest cells; of RNA from distal outflow tract, proximal outflow tract, and atrioventricular tissue of embryonic chick hearts; and of RNA isolated from left and right cranial tissues, including the early heart fields. These screens have resulted in the identification of the five cDNA clones presented here, which are expressed in the cardiac neural crest, outflow tract and developing heart in patterns that are unique in heart development.