Geometric and muscle physiological factors of the frank-starling mechanism

Summary The relation between left-ventricular stroke volume (SV) and end-diastolic volume (EDV) was determined based on angiocardiographic measurements in 10 open-chest minipigs under varying filling conditions (blood letting or infusions). The results were compared with a theoretical relation calculated under the assumption of varying EDV but constancy of myocardial properties.In contrast to the linear increase of SV as a function of EDV as found in the animal experiments, the calculated curve reveals a maximum near the normal operating point with a decrease in the range of higher EDV. It can be concluded that the well-known increase of SV with increasing ventricular filling, beyond the normal EDV, is almost completely due to muscle physiological factors (mainly increase in Ca²⁺ sensitivity of the contractile apparatus), whereas the decrease of SV in the range of low filling pressure is mainly due to the geometrical conditions.Supported by the Deutsche Forschungsgemeinschaft (Ja 172/14-2)     

心脏造影射血分数的轴线回归法

本文介绍一种简单准确计算造影射血分数(EFa)方法。动态分析42例受检者左室射血1/3、1/2期和舒、缩末四帧右前斜30°电影造影影象,表明射血各期轴线总缩短率(T％△a)和相应EFa呈密切正相关。直线回归关系为EFa=0.1712+1.3303T％△a,r=0.880,曲线回归关系为EFa=0.0396+2.4874T％△a-1.9787(T％△a)~2,r~2=0.981。由另外10例受检者的T％△a按直线方程、曲线方程和面积-长度法求得的EF分别为0.469±0.179、0.464±0.208和0.482±0.208。三者间无统计学差异(P>0.05)。说明回归法准确简单,不需要求面积和容积,初步认为轴线回归法可替代传统的面积-长度法计算EFa。     

M-mode contrast echocardiography in patients with univentricular heart

M-mode echocardiographic peripheral venous contrast studiesof 23 patients with complex forms of univentricular heart werecompared with cineangiocardiographic findings obtained in traditionaland axial projections. The morphology of the main ventricularchamber (left type 16, right 6, indeterminate 1), of the rudimentarychamber (16 anterior and four posterior), the type and modalitiesof atrioventricular connections (common AV valve 6, two AV valves13, absent left connection 4), the connections and the interrelationshipsof the great arteries as well as the degree of obstruction ofthe outlet portions were analysed by both methods. M-mode echocardiographydid not provide valuable information about atrioventricularvalve morphology: in three cases discordant results were found.Contrast studies improved the diagnostic capabilities and allowedidentification of double inlet connection in 10 out of 11 patientsand of single inlet in four out of five patients respectively.     

Right and left ventricular pump function in infants and children with primary myocardial disease presenting with heart failure

Summary Right and left ventricular (RV, LV) function were evaluated by quantitative bi-plane cineangiocardiography in 20 patients, aged 1 day to 6 years, who had primary myocardial disease presenting with heart failure. RV end-diastolic volume (RVEDV) was 157%±63% ( ±SD) of normal (P<.01), and RV ejection fraction (EF) was 0.39±0.16 (normal, 0.65±0.08) (P<.01). Left Ventricular end-diastolic volume (LVEDV) was 331%±172% of normal and LVEF 0.26±0.12 (normal, 0.68±0.05); both values were different from normal (P<.01) and also different from corresponding RV values (P<.01). RVEDV was larger than LVEDV in only four patients, these four patients being the youngest patients in the entire group, all 10 days of age or younger. A subgroup of 14 patients with subnormal RVEF (RVEF> –2 SDs of normal) were compared with six patients with normal RVEF. Patients with subnormal RVEF had larger left ventricles, lower LVEFs, and higher RV peak systolic pressure than those with normal RVEF (P<.05 for all three comparisons). A separate subgroup of ten patients who died was compared with a subgroup of eight surviving patients followed up for one to four years after diagnosis. Patients who died had lower values for LVEF and LV systolic output and higher values for LV end-diastolic pressure than did survivors. There were no significant differences between patients who died and survivors in any of the RV variables measured. RV functional abnormalities were generally present in both infants and children who had myocardial disease presenting with heart failure and may especially contribute to the symptoms in infants.Supported in part by grant HL 21985-01 from the National Heart, Lung, and Blood Institute     

Aortic implantation of the anomalous left coronary artery from the pulmonary artery: One-year angiographic follow-up

Surgical aortic reimplantation of the anomalous origin of the left coronary artery from the pulmonary artery in a 16-year-old boy is reported. One-year angiographic follow-up showed patency of the reimplanted coronary ostium, normalization of left ventricular segmental wall motion and volume, and reduction in the caliber of the right coronary artery. This is the surgical correction procedure of choice in anatomically feasible cases.     

冠状动脉病变对节段室壁运动的影响

目的：探讨冠心病人冠状动脉病变对节段室壁运动的影响。方法：对34例心绞痛患者、30例心梗患者与36例正常对照者行选择性冠状动脉造影和左心室造影,冠状动脉病变结合电影影像和数字减影影像进行专家目 测和自动测量对照分析,节段室壁运动研究采用室壁运动自动分析软件进行分析,冠状动脉病变按一支或一支以上血管有50％以上狭窄确定诊断。结果：冠状动脉病变部位直接影响局部室壁运动。结论：室壁运动异常部位与冠状动脉病变部位一致。     

上腔静脉综合征的介入治疗

目的：探讨肺癌源性上腔静脉综合征治疗方法及评价临床疗效。材料和方法：患者１５例,右侧中央型肺癌并纵隔淋巴结转移１３例,右下肺癌并纵隔淋巴结转移２例。１４例行支气管动脉灌注（ＢＡＩ）抗癌药１～４次,１例行ＢＡＩ及上腔静脉支架治疗。结果：ＢＡＩ后所有患者上腔静脉综合征均有不同程度缓解,但远期均有复发;１例行ＢＡＩ及上腔静脉支架治疗病例术后随访１１个月无症状复发。结论：ＢＡＩ可以有效地缓解肺癌源性上腔静脉综合征症状,但远期易发,结合血管内支架治疗,则可以达到较好的效果。     

Utility of real-time three-dimensional echocardiography for Duchenne muscular dystrophy with echocardiographic limitations

Duchenne muscular dystrophy (DMD) is strongly associated with a unique form of dilated cardiomyopathy. Cardiac complications are the leading cause of death in DMD; thus, longitudinal assessments and early intervention for cardiac dysfunction are necessary to improve prognosis. Two-dimensional echocardiography, which is routinely used for cardiac assessment, has some limitations for quantitative analyses in DMD patients with thoracic deformities and regional wall motion abnormalities in the left ventricle. Recently, real-time three-dimensional echocardiography has emerged as a feasible tool for cardiac assessment in various cardiac diseases. The aim of this study was to examine the utility of this technology in DMD. We evaluated left ventricular ejection fraction (LVEF), a major parameter of left ventricular function, in 17 male DMD patients. LVEF values measured by real-time three-dimensional echocardiography were compared with those determined by two established nuclear cardiology methods: “the first-pass method of radionuclide angiocardiography” and “quantitative electrocardiogram-gated single-photon emission computed tomography”. A good correlation was observed for LVEF values, particularly between real-time three-dimensional echocardiography and “the first-pass method of radionuclide angiocardiography” (r = 0.90, p < 0.05). Thus, real-time three-dimensional echocardiography can provide an accurate measurement of LVEF in DMD patients with echocardiographic limitations.     

Congenital aortic arch anomalies: diagnosis using contrast enhanced magnetic resonance angiography

Congenital aortic arch anomalies occur most commonly in children. The disease can be classified into three types: ① obstructive congenital abnormalities, including coarctation of aorta (CoA) and interruption of aortic arch (IAA); ② non-obstructive congenital abnormalities, including double aortic arch and others; ③ congenital shunt abnormalities, including different types of patent ductus arteriosus (PDA). Management of patients with congenital aortic arch anomalies relies on imaging. Routine imaging modalities, such as conventional X-ray plain film and transthoracic echocardiography (TTE), have been recently complemented by magnetic resonance imaging (MRI).