Examination of the newborn: The innocent heart murmur

The role of the health professional is constantly changing and evolving, and as areas of practice expand, this requires advanced skills. The midwife in extending her role to become professionally competent in the examination and assessment of the newborn facilitates the provision of holistic care for the woman, infant and family.This is a case study report of an infant diagnosed with an innocent heart murmur on the first neonatal examination. It explores the transitional process of a midwife extending her role in performing the neonatal examination and critically evaluating the neuro-behavioural physiological assessment of the infant and covers areas of debate including which practitioner should be performing the examination and the timing of the examination.     

The anatomy of an arrhythmia

Computer simulations are potentially effective approaches to unraveling the causes of lethal heart rhythm disorders. In this issue of the JCI, Xie et al. have embedded a well-characterized dynamic mechanism for arrhythmia development in an anatomically realistic computer model of the heart. Their demonstration that this simple mechanism governs the behavior of the complex model may provide a new target for strategies to prevent sudden death.     

Cardiac hemodynamics in alcoholic patients with chronic liver disease and a presystolic gallop

10 male subjects with chronic liver disease and with normal cardiovascular findings, except for the presence of a presystolic gallop, underwent right and left heart catheterization. In general, all of the patients had a high resting cardiac output, narrow arteriovenous oxygen difference, a low peripheral vascular resistance, and normal left ventricular end-diastolic pressures and volumes. The plasma volume was increased in the seven patients in which it was determined.On exercise, all of the patients demonstrated a significant increase in the left ventricular end-diastolic pressure and mean pulmonary artery pressure, while the stroke index remained the same or fell in seven of the subjects.It appears logical to assume that the excessive intake of alcohol is associated with an impairment in the metabolic and contractile properties of the left ventricle and the resultant hemodynamic effects may not be readily discerned in the resting state. However, upon exercise these patients, with a congested circulation, can show abnormal cardiac dynamics.     

Left ventricular outflow tract presystolic flow velocity--another marker of left ventricular diastolic function

Left ventricular outflow tract (LVOT) presystolic flow velocities were studied using pulse doppler echocardiography in 30 normal persons. Thirty patients of mild hypertension with transmitral flow velocity pattern suggestive of impaired relaxation were also studied. Transmitral flow velocity pattern was correlated with LVOT presystolic flow velocities in the two groups. Hypertensive patients had significantly higher transmitral A wave velocity (p < 0.001) and significantly lower transmitral E wave/A wave velocity ratio (p < 0.001) as compared to normal group. LVOT presystolic flow velocities had significant direct correlation with transmitral A wave velocity (p < 0.01) and significant inverse relation with transmitral E wave/A wave velocity ratio (p < 0.05). Our observations suggest that increased LVOT presystolic flow peak velocity can also be used as another marker of impaired left ventricular compliance during atrial contraction. More work is needed to establish exact status of this preliminary observation.     

超声心动图在新生儿心脏杂音检查中的应用价值

目的探讨超声心动图在新生儿心脏杂音检查中的应用价值。方法5581例新生儿中听诊有心脏杂音的49例进行常规及剑下各切面超声心动图检查,按心脏三级顺序分段法检查并做出诊断。结果检出先天性心脏病27例,占总人数的4．8％0,其中室间隔缺损15例,占55．5％;房间隔缺损10例,占37．1％;原发性肺动脉高压1例,占3．7％;复杂心脏畸形1例,占3．7％;检出其他心脏病变22例,占总人数的3．9％0,其中未闭合的动脉导管12例,二尖瓣和／或三尖瓣反流9例,左室假腱索1例。结论彩色多普勒超声心动图准确、无创,为新生儿心脏杂音的诊断和鉴别诊断提供了方便、快捷的检查手段,使新生儿的先天性心脏病能得到早期诊断。     

Relation of presystolic wave on doppler examination to syntax score in patients with acute myocardial infarction

Background

There are few reports demonstrating a relationship between presystolic wave (PSW) and left ventricular function. The aim of the present study was to investigate the associations between PSW and angiographic and echocardiographic characteristics of patients with acute myocardial infarction (AMI).

Methods

We studied 348 consecutive patients with AMI. Pulsed Doppler-echocardiography was used to assess the both diastolic functions and presence of PSW from left ventricular outflow tract. Patients were divided into two groups by the presence or absence of PSW. The Syntax score (SXscore) was calculated from baseline angiograms to assess the complexity and severity of coronary artery disease.

Results

The overall prevalence of PSW was 51.1%. Compared to patients without PSW, patients with PSW presence had greater left ventricular ejection fraction (LVEF), greater septal a′ velocity, lower mitral E and septal e′ velocity and lower E/A and e′/a′ ratios. Also, median SXscore were significantly lower in the PSW presence group compared to PSW absence group [1 (6–14) vs. 12 (7–18), P?=?0.013]. In addition, the number of patients with high-SXscore (>?16) was significantly lower in PSW presence group (24 vs. 42), (P?=?0.006). In multiple logistic regression analysis, absence of PSW found independent predictor of high-SXscore (OR 2.297 95% CI 1.235–4.272; P?=?0.009).

Conclusions

We found that the presence of PSW was related with higher LVEF, lower SXscore and lower stage diastolic dysfunction in patients with AMI. PSW may be used in prediction of the coronary artery disease complexity and it could help risk stratification in patients with AMI.

     

The mitral valve chordal system as a cause of innocuous heart murmur]

To specify the role of morphofunctional features of mitral chorda in forming innocent cardiac murmur (ICM), 107 and 20 young men with or without ICM, respectively, were examined clinically and instrumentally at rest, muscular load and hyperventilation. Echocardiography was recorded in one-dimentional, sectoral and Doppler regimens. Fluttering chorda (FC) of the mitral valve (MV) manifesting by hyperkinesia of usually fixed MV chorda, its early systolic dislocation into the left ventricular outflow tract was registered in 34.5% of ICM patients, 11.2% of them had echocardiographic evidence of the chordal shift in the systole into the above tract. In ICM-free subjects the phenomenon FC and the systolic chordal shift were absent (the difference was significant, p < 0.05). The FC phenomenon is attributed to local dysfunction of the papillary muscles and may produce distinct labile nonregurgitation systolic murmur.     

特发性室性心律失常的心率变异性分析

目的分析特发性室性心律失常(IVA)患者导管射频消融(RFCA)术前动态心电图的检测结果,探讨自主神经系统(ANS)在IVA形成机制中的作用。方法纳入116例解放军总医院住院行RFCA的患者。分析术前24 h动态心电监护等资料,比较不同起源IVA的患者间心率变异性(HRV)指标的差异。结果 116例患者中男性59例,女性57例,年龄10~82(43.3±15.7)岁。起源于右室流出道(RVOT)80例、左室流出道(LVOT)12例、左室间隔9例、右室流入道7例、左室其他部位8例。在5组患者间的24 h室性早搏总数、正常窦性心律R-R间期标准差(SDNN)、正常窦性心律R-R间期平均值的标准差(SDANN)、全程相邻正常窦性心律R-R间期之差的均方根值(RMSSD)、在一定时间内相邻两正常心动周期差值50 ms的个数所占的百分比(PNN50)、低频功率(LF)、高频功率(HF)的差异无统计学意义;男性患者和女性患者组间的差异无统计学意义。LF/HF1与LF/HF1的患者组间相比构成比差异有统计学意义(P0.05)。夜间23:00~7:00室早的次数占24小时总室性早搏的次数30%组和30%组,两组相比构成比差异有统计学意义(P0.05)。结论不同起源部位的IVA患者的HRV存在差异,提示自主神经在不同起源部位的IVA发生过程中发挥不同的作用。