130例Ⅱ孔房间隔缺损伴肺动脉高压患者的临床分析

目的 :探讨Ⅱ孔房间隔缺损 (房缺 ,ASD)继发肺动脉高压的相关因素以及妊娠在女性房缺患者肺动脉高压形成过程中的作用。方法 :收集 1993年 1月至 2 0 0 0年 4月北京安贞医院收治的伴肺动脉高压的房缺患者 130例。按照年龄、性别、房缺直径、肺阻力大小分组 ,进行回顾性临床分析。结果 :1 随着年龄的增长 ,男性和女性房缺患者的肺动脉高压发病率均增高 ,而女性更为显著。 2 房缺直径大小与肺动脉压力间无显著相关。 3 有过妊娠史的女性患者 ,继发肺动脉高压的趋势较无妊娠史的女性患者和同年龄的男性患者更明显。结论 :房间隔缺损继发肺动脉高压有多种相关因素。有过妊娠史的女性房缺患者 ,妊娠期间血容量显著增加以及血液高凝状态造成远端肺小动脉血栓形成 ,可能参与并促进了肺动脉高压的发展。     

Continuous epoprostenol therapy and septal defect closure in a patient with severe pulmonary hypertension

A 31‐year‐old woman with exertional dyspnea diagnosed as having atrial septal defect (ASD) with severe pulmonary hypertension (PH). Intravenous epoprostenol therapy was started to improve PH. Although pulmonary arterial pressure decreased, her symptoms remained in class III of WHO functional class, probably because of exacerbation of the left‐to‐right shunt caused by the reduction of pulmonary vascular resistance (PVR). Transcatheter atrial septal closure was therefore performed. Soon after the procedure, additional reduction in pulmonary arterial pressure was achieved. Her symptoms improved and oxygen inhalation was discontinued. One year after the procedure, although intravenous epoprostenol was still required, her symptoms had improved to class I of WHO functional class without exacerbation of PH. Transcatheter atrial septal closure after lowering PVR by intravenous epoprostenol would be a novel therapy for patients with ASD accompanied by PH. © 2009 Wiley‐Liss, Inc.     

Frequency of severe pulmonary hypertension complicating "isolated" atrial septal defect in infancy

Atrial septal defects (ASDs) are typically asymptomatic in infancy and early childhood, and elective defect closure is usually performed at ages of 4 to 6 years. Severe pulmonary hypertension (PH) complicating an ASD is seen in adulthood and has only occasionally been reported in small children. A retrospective study was undertaken to evaluate the incidence of severe PH complicating an isolated ASD and requiring early surgical correction. During a 10-year period (1996 to 2006), 355 pediatric patients underwent treatment for isolated ASDs either surgically or by catheter intervention at 2 tertiary referral centers. Two hundred ninety-seven patients had secundum ASDs, and 58 had primum ASDs with mild to moderate mitral regurgitation. Eight infants were found with isolated ASDs (6 with secundum ASDs and 2 with primum ASDs) associated with significant PH, accounting for 2.2% of all patients with ASDs at the centers. These 8 infants had invasively measured pulmonary artery pressures of 50% to 100% of systemic pressure. They were operated in the first year of life and had complicated postoperative courses requiring specific treatment for PH for up to 16 weeks postoperatively. The ultimate outcomes in all 8 infants were good, with persistent normalization of pulmonary pressures during midterm follow-up of up to 60 months (median 28). All other patients with ASDs had normal pulmonary pressures, and the mean age at defect closure was significantly older, at 6.2 years for secundum ASDs and 3.2 years for primum ASDs. In conclusion, ASDs were rarely associated with significant PH in infancy but then required early surgery and were associated with excellent midterm outcomes in these patients.     

Secundum atrial septal defect with severe pulmonary hypertension. Open lung biopsy diagnosis of operative indication

In 14 of 15 patients ranging in age from 1 to 62 years (mean of 34) with secundum atrial septal defect (ASD) and pulmonary hypertension over 60 mm Hg peak pressure, operative indication was determined by morphometric diagnosis of open biopsy of lung specimens. In one patient, open lung biopsy was also performed during corrective surgery. Pulmonary arterial changes in the 15 patients were grouped into four classifications as follow: (1) plexogenic pulmonary arteriopathy (six patients); (2) thromboembolism in small pulmonary arteries (three patients); (3) "musculoelastosis," intimal proliferation of longitudinal smooth muscle bundles and elastic fibers (three patients); and (4) combinations of (1), (2) or (1), (3) (three patients). We conclude concerning the operative indication that group 2 patients are operable in all cases and group 1 patients with Yamaki's index of pulmonary vascular disease of 2.2 or less; group 3 patients with the absence of complete occlusion of the small pulmonary arterial lumen are operable, and patients with clear evidence of severe plexogenic pulmonary arteriopathy in group 4 are not operable. Comparative analysis of pulmonary pathology and hemodynamic performance revealed that open lung biopsy should be performed to determine operative candidacy in cases with a pulmonary vascular resistance greater than 8 unit X m2, which is considered to represent the borderline of operability.     

Extensive pulmonary arterial thrombi in situ in association with atrial septal defect.

A 48-year-old woman with cyanosis was referred for investigation of atrial septal defect (ASD). Blood gas analysis on admission revealed moderate hypoxemia, and a pressure study during right heart catheterization revealed pulmonary hypertension (PH). Spiral computed tomography (CT) scan disclosed extensive thrombi in dilated large symmetrical pulmonary arteries with clear lung fields, and large strand-like thrombi on the inner surface of the pulmonary arterial wall along the vascular curvature were visualized by virtual CT angioscopic imaging. The thrombi were eventually considered to be not thromboemboli but thrombi in situ, because no segmental or larger defects were detected in the lung perfusion scan, although it showed cardiovascular imprints and an inhomogeneously decreased perfusion pattern. Pulmonary thrombi in situ are an uncommon manifestation in patients with ASD, and have not been described from the evidence of both CT and lung perfusion scans. The findings indicate that pulmonary thrombi in situ are not associated with occlusion of the large pulmonary arteries and the resultant development of PH. The patient was conservatively treated with medication, and the pulmonary thrombi did not show significant change with anticoagulant therapy. She died suddenly at the age of 51 years.     

Valved patch for ventricular septal defect with pulmonary arterial hypertension

From March 1998 to December 2004, 16 acyanotic patients aged 2 to 22 years (mean, 7 +/- 5.7 years) with a large ventricular septal defect and elevated pulmonary vascular resistance (9.6 +/- 3.8 Wood units) underwent surgery. A Gore-Tex patch with a 5-8 mm longitudinal slit in the center was used. A piece of pericardium was sewn around the slit on one side of the patch, except for the upper quarter. In all patients, the defect was closed with a trimmed patch and the pericardial aspect was placed on the left ventricular side to allow right-to-left shunting. Echocardiography on the day of operation revealed a right-to-left shunt in 6 cases. Two patients (12.5%) died in the early postoperative period due to frequent episodes of pulmonary hypertensive crisis and persistent severe pulmonary hypertension. In 3 years of follow-up, pulmonary vascular resistance gradually decreased in all but one patient in whom it increased with a right-to-left shunt and cyanosis. Insertion of a valved patch seems to be a promising technique to decrease morbidity and mortality in severe pulmonary arterial hypertension.     

Coronary arteriographic findings in the patients with atrial septal defect and pulmonary hypertension (ASD + PH)--compression of left main coronary artery by pulmonary trunk

The characteristic narrowing of left main coronary artery (LMCA) was found in 44% of patients (pts) with atrial septal defect and pulmonary hypertension (ASD + PH). The cause of the narrowing is thought to be the compression by pulmonary trunk (PT). Cardiac catheterization and coronary arteriography (CAG) were performed in 38 pts with ASD ranging in age from 15 to 62 years. We defined abnormal narrowing as 50% or more stenosis of AHA classification. Sixteen pts (42%) had PH, and of these pts 7 show the abnormal narrowing of LMCA. (18% of all pts with ASD, 44% of pts with ASD + PH). They had no signs of syphilis or aortitis. Of the pts with PH, those with abnormal LMCA revealed higher pulmonary artery mean pressure than those with normal LMCA (43.6 +/- 17.3 and 27.1 +/- 5.5 mmHg respectively. p less than 0.01). Other parts of coronary arteries are intact in all pts. These findings suggest that the LMCA abnormality relates to PH. In all cases with LMCA abnormality the narrowing revealed some special features indicate the cause of narrowing is compression. First, the most severe part of narrowing was the coronary ostium, and severity reduced gradually as distal LMCA. Second, the narrowing was estimated most severely in the view of LAO 20, but almost normal in the view of RAO 30. This finding suggests the narrowing is ellipsoid. Third, the shape of LMCA changed in the different phase of cardiac cycle. In the systole, the cranial border of LMCA was convex, but in the diastole it was concave. This indicates LMCA was soft and compressed.(ABSTRACT TRUNCATED AT 250 WORDS)     

1岁以下婴儿室间隔缺损伴肺动脉高压的外科治疗

目的　探讨婴儿室间隔缺损 (VSD)伴肺动脉高压 (PH)外科治疗的结果和经验。方法　对 6 0例 1岁以下婴儿室缺伴肺高压的手术治疗进行总结。年龄 2～ 11个月 ,平均 (6 2 3± 2 6 0 )个月 ,体重 3～ 10kg,平均 (5 5 0± 1 2 6 )kg。术前中度以上肺高压 5 3例 (88 8% )。结果　全组手术死亡3例 (5 % ) ,手术死亡的主要原因是肺动脉高压危象和急性心包填塞。术后主要并发症为肺动脉高压危象 ,术后出血和肺部感染。结论　婴儿室缺伴肺高压应尽早手术治疗。术前、术后支持疗法 ,术中加强心肌保护、提高手术技巧 ,术后注意呼吸、循环监测 ,加强呼吸道管理 ,防治可能出现的并发症是手术治疗成功的关键。     

Home-made fenestrated amplatzer occluder for atrial septal defect and pulmonary arterial hypertension

We report the management of a patient with secundum atrial septal defect (ASD) and severe pulmonary hypertension. A 65-year-old male with recently diagnosed atrial septal defect was referred to our centre for decompensated right heart failure with rest and exercise induced dispnea and severe pulmonary hypertension. Right heart catheterization confirmed a mean pulmonary pressure of about 55 mmHg and a Qp/Qs of 2.7. An occlusion test with a compliant large balloon demonstrated partial fall of pulmonary arterial pressure. The implantation of a home-made fenestrated Amplatzer ASD Occluder (ASO) was planned in order to decrease left-to-right shunt and promote further decrease of pulmonary arterial pressure in the long-term. Thus, by means of mechanical intracardiac echocardiography study with a 9F 9 MHz UltraIce catheter (Boston Scientific Corp.), we selected a 34 mm ASO for implantation. Four millimeter fenestration was made inflating a 4 mm non-compliant coronary balloon throughout the waist of the ASO, which was successfully implanted under intracardiac echocardiography. After six months, a decrease of pulmonary arterial pressure to 24 mmHg and full compensated right heart failure was observed on transthoracic echocardiography and clinical examination. This case suggests that transcatheter closure with home-made fenestrated ASD in elderly patients with severe pulmonary hypertension is feasible.     

Pulmonary vascular disease in secundum atrial septal defect with pulmonary hypertension

Histopathologic and morphometric studies of small pulmonary arteries were performed in 16 cases of secundum atrial septal defect (ASD) and severe pulmonary hypertension. Besides typical plexogenic arteriopathies found in six cases, organized microthrombi and what we call "musculoelastosis," that is, proliferation of longitudinal smooth muscle bundles and elastic fibers, were seen in small pulmonary arteries in three and four cases, respectively. These changes were observed co-existing in the remaining three cases. Thrombi of the small pulmonary arteries and musculoelastosis were the forms of pulmonary vascular disease characteristically found in the older patients with both ASD and pulmonary hypertension. Yamaki's index of pulmonary vascular disease, though effective in describing severity of plexogenic arteriopathy, proved to be less so for the intimal lesions in old microthrombi and for musculoelastosis. Among the cases with plexogenic arteriopathy, there was a positive significant correlation between the medial thickness of small pulmonary arteries and peak arterial pressure, which, however, was not demonstrated when all the cases of ASD were included.     

影响儿童继发孔型房间隔缺损肺动脉压力的因素

目的 探讨儿童继发孔型房间隔缺损（ASD）肺动脉压力的影响因素.方法 回顾性分析2000年4月至2011年1月沈阳军区总医院收治的10岁以下继发孔型ASD患者,全部患儿在氯胺酮全麻下行心导管检查测肺动脉压力,并完成封堵治疗.收集患者性别、年龄、身高、体重及体表面积、ASD直径、心胸比值和肺动脉收缩压、舒张压、平均压,术后超声心动图随访1年,并按缺损直径和年龄分组.结果 本研究共359例患儿,男130例（36.2％）.平均年龄（5.8±2.2）岁（2～10岁）,平均体重（21.0±7.1） kg （10～57kg）,平均缺损直径（13.6±5.6） mm（5～30 mm）,体表面积矫正缺损直径为（17.0±7.1） mm/m2（1.3～41.0 mm/m2）,平均肺动脉收缩压（40.8±8.7 mmHg） （15～67 mmHg）（1 mmHg=0.133 kPa）.318例（88.6％）患者心导管测量存在肺动脉高压,所有患者术前及术后1、3、6、12个月超声估测肺动脉压均正常;肺动脉压力不随房间隔缺损直径增大而升高（P＞0.05）;10岁以下儿童肺动脉压力与年龄和体表面积矫正的缺损直径无相关性（P＞0.05）.结论 10岁以下继发孔型ASD患儿,心导管检查所测肺动脉压力与患儿年龄和体表面积矫正的缺损直径无关,与缺损直径无简单线性关系,压力不随缺损直径增大而升高.     

Lung biopsy diagnosis of operative indication in secundum atrial septal defect with severe pulmonary vascular disease

OBJECTIVE: Surgical indication was determined by lung biopsy in 91 patients with secundum atrial septal defect (ASD) and severe pulmonary hypertension > 70 mm Hg of pulmonary arterial peak pressure and/or pulmonary vascular resistance of > 8 U/m(2). METHODS AND RESULTS: Pulmonary vascular disease (PVD) in ASD was classified into four types: (1) Musculoelastosis consisting of longitudinal muscle bundles and elastic fibers; surgery is indicated no matter how severely the peripheral small pulmonary arteries are occluded. Surgery was performed in all of the 20 patients, and the postoperative course was uneventful. (2) Plexogenic pulmonary arteriopathy: surgery is indicated for a PVD index < or = 2.3. Surgery was performed in 25 of the 32 patients. The remaining seven patients for whom surgery was not indicated are under follow-up observation. No deaths have occurred among the 32 patients. (3) Thromboembolism of small pulmonary arteries: Surgery is indicated for all such cases. Surgery was indicated in all of the five patients. (4) Mixed type of plexogenic pulmonary arteriopathy and musculoelastosis: Surgery is indicated if the collateral is not observed. Surgery was performed in 15 of the 25 patients. The remaining 10 patients for whom surgery was not indicated are under follow-up observation. Nine of these 91 patients associated with primary pulmonary hypertension were eliminated from this study. CONCLUSION: No deaths due to PVD occurred among the 82 patients who underwent lung biopsy diagnosis. Lung biopsy diagnosis is concluded to be very effective.     

带孔房间隔分流器治疗肺动脉高压犬的短期疗效初探

目的初步探讨带孔房间隔分流器治疗肺动脉高压犬模型的短期疗效。方法健康雄性比格犬36只, 犬龄1～2岁, 采用简单随机抽样法分为经导管球囊扩张房间隔造口术(BAS)+分流器组、BAS组和无造口组3组, 每组12只。在犬右心房内注射脱氢野百合碱(1.5 mg/kg), 建立肺动脉高压模型。建模成功后, BAS+分流器组犬行BAS, 术后置入带孔房间隔分流器, BAS组犬行球囊扩张房间隔造口术, 无造口组犬不予任何干预。于建模前, 建模后2个月, 手术治疗后1、3、6个月, 分别测量各组犬的血流动力学指标及血N末端B型利钠肽原(NT-proBNP)水平。于手术治疗后1、3、6个月对BAS组和BAS+分流器组犬行超声心动图检查, 观察分流器及房间隔造口的开通情况。于手术治疗后1、3、6个月各组分别处死3只犬, 取心脏房间隔组织及房间隔分流器进行大体观察, 观察分流器内皮化情况;取肺组织进行苏木素-伊红(HE)染色, 观察肺中小血管附近炎症细胞浸润以及肺血管内膜增厚和狭窄的情况。结果 2只犬在建模后24 h内死亡, 剩余34只犬, 其中BAS+分流器组12只、BAS组11只、无造口组11只。与B...     

Isolated atrial septal defect with pulmonary vascular obstructive disease--long-term follow-up and prediction of outcome after surgical correction

We examined the cases of 702 patients found to have isolated atrial septal defect of the secundum or sinus venosus type at catheterization from 1953 to 1978. Forty patients (6%), 34 women and six men, had pulmonary vascular obstructive disease, with a total pulmonary resistance greater than 7 U/m2; of these patients 26 (mean age 47 years) underwent surgical closure and 14 (mean age 44 years) received medical treatment. All patients were followed for at least 4 years, with a median follow-up of 12 years. At the most recent follow-up, 17 of the 40 patients were dead. Of the 22 surgically treated patients with total pulmonary resistance less than 15 U/m2, 19 were alive with significant regression of symptoms. All four surgically treated patients with total pulmonary resistance greater than or equal to 15 U/m2 were dead. Of the five medically treated patients with total pulmonary resistance less than 15 U/m2, four had died, and one was alive with significant progression of symptoms. Of the nine medically treated patients with total pulmonary resistance greater than or equal to 15 U/m2, six had died and the three survivors had progression of symptoms. In the surgically treated group, the following variables correlated with survival: total pulmonary resistance (p less than .00001), pulmonary arteriolar resistance (p less than .00001), pulmonary-to-systemic resistance ratio (p = .004), systemic arterial oxygen saturation (p = .005), and pulmonary arterial oxygen saturation (p = .007). In conclusion: (1) Atrial septal defect with high total pulmonary resistance is uncommon and predominates in adult female patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Acute haemodynamic effects of nifedipine in patients with ventricular septal defect

The haemodynamic effects of nifedipine were studied in 14 patients (aged 8-14 years, seven male and seven female) with ventricular septal defect with and without pulmonary hypertension. All underwent left and right heart catheterisation. In each patient the pressures and heart rate were measured and blood samples were taken for oximetry before and after sublingual administration of 10 mg nifedipine. In eight patients with ventricular septal defect without pulmonary hypertension (mean pulmonary artery pressure less than 20 mm Hg) nifedipine significantly reduced the mean aortic pressure and systemic vascular resistance, and significantly increased heart rate. The other haemodynamic indices did not change significantly. In six patients with ventricular septal defect complicated by pulmonary hypertension (mean pulmonary artery pressure greater than 20 mm Hg) nifedipine significantly increased systemic output, stroke volume, and heart rate, and significantly reduced systemic vascular resistance and the pulmonary to systemic flow ratio. The other haemodynamic indices did not change significantly. Nifedipine had a beneficial effect in patients with ventricular septal defect complicated by pulmonary hypertension. It reduced the left to right shunt and increased the stroke volume. This effect was not seen in patients with ventricular septal defect uncomplicated by pulmonary hypertension.     

Right ventricular function in adults with pulmonary hypertension with and without atrial septal defect

Using equilibrium (gated) radionuclide ventriculography, right ventricular (RV) function was studied in 22 adults with pulmonary hypertension and in 16 patients without evidence of cardiac disease. To assess the effect of volume overload on RV performance in pulmonary hypertension, RV ejection fractions were compared in patients with and without left-to-right shunts due to atrial septal defect (ASD). In addition, the effect of ASD repair on RV function was examined. In 14 patients with pulmonary hypertension without RV volume overload (group I), the RV ejection fraction (0.35 ± 0.11, mean ± standard deviation [SD]) was significantly lower than in the normal group (0.47 ± 0.11, p < 0.01). In 8 patients with left-to-right shunts due to ASD (group II) and with RV systolic pressures similar to those in group I, the mean RV ejection fraction (0.53 ± 0.15) was normal and was significantly higher than in group I (p < 0.01). Right ventricular end-diastolic volumes, estimated from combined radionuclide and hemodynamic data, were higher (p < 0.01) in group II patients (171 ± 70 ml/m²) than in group I patients (70 ± 13 ml/m²). In 5 patients who underwent isolated shunt repair, mean RV ejection fraction decreased postoperatively from 0.57 ± 0.17 to 0.40 ± 0.12 (p < 0.05). It is concluded that (1) pulmonary hypertension frequently causes a decrease in RV systolic function due to abnormal afterload; (2) in patients with RV volume overload due to left-to-right shunt, systolic function, as measured by the ejection fraction, remains normal despite pulmonary hypertension, possibly through the Starling mechanism; and (3) RV systolic function often decreases after repair of an ASD.     

Spontaneous embolization of an atrial septal defect occluder device into the left ventricular outflow tract in a patient with pulmonary stenosis

A 24‐year‐old man was admitted to our outpatient clinic for his routine checkup of consecutively percutaneously treated atrial septal defect (ASD) and pulmonary valvular stenosis 45 days ago. A 24 mm ASD occluder device was implanted under transthoracic echocardiographic guidance and 80 mm Hg peak‐to‐peak pulmonary valvular gradient decreased to 20 mm Hg gradient after pulmonary valve dilatation with 23 mm NUMED II transluminal valvuloplasty catheter balloon. Atrial septal defect (ASD) closure is now routinely performed using a percutaneous approach under echocardiographic guidance especially transthoracic echocardiography (TEE). Centrally located, ostium secundum type and less than 3.5 cm in size are considered ideal for device closure. Although there is considerable variation in size and location of the defects, TEE guidance is quite important for this proportion of ASDs. The selection of patients for percutaneous transcatheter closure of a secundum ASD requires accurate information regarding the anatomy of the defect such as its maximal diameter and the amount of circumferential tissue rims.     

Long-term outcome of patients operated for large ventricular septal defects with increased pulmonary vascular resistance

BACKGROUND: There is a paucity of data regarding the long-term outcome of patients operated for ventricular septal defect with severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. METHODS AND RESULTS: We evaluated the long-term follow-up results of a selected cohort of patients with nonrestrictive ventricular septal defect and elevated pulmonary vascular resistance (>6 Wood units). Thirty-eight patients, median age 7.5 years (range 6 months-27 years), with nonrestrictive ventricular septal defect with severe pulmonary hypertension were operated between 1985 and 1996 at our institute. Preoperative pulmonary vascular resistance, ratio of pulmonary blood flow to systemic blood flow, and ratio of pulmonary vascular resistance to systemic vascular resistance were 7.63+/-1.8 Wood units, 1.9+/-0.48, and 0.41+/-0.12, respectively. The majority (68.4%) had perimembranous ventricular septal defect. Thirty patients (79%) had a good outcome and were asymptomatic at a mean follow-up of 8.7 years, with significant reduction in pulmonary artery pressures. Eight patients (21%) had a poor outcome, which included 5 immediate postoperative deaths, 1 late death and 2 surviving patients with persistent severe pulmonary arterial hypertension. There was no significant difference regarding hemodynamic parameters at baseline between those who had a good outcome and those who did not. Eleven patients with a preoperative pulmonary blood flow to systemic blood flow ratio of <2:1. who had a good outcome following surgery, underwent repeat catheterization at follow-up. There was a significant reduction in their mean pulmonary vascular resistance (8.03+/-1.4 v. 4.16+/-1.6 Wood units, p=0.001) and pulmonary vascular resistance to systemic vascular resistance ratio (0.41+/-0.12 v. 0.19+/-0.06, p=0.05). CONCLUSIONS: The late results of surgery on this selected group of patients with nonrestrictive ventricular septal defect with high pulmonary vascular resistance are encouraging. Operative correction of the ventricular septal defect should be actively considered in all children presenting with nonrestrictive ventricular septal defect with a significant left-to-right shunt, despite moderately elevated pulmonary vascular resistance. Even among older patients with ventricular septal defect and moderately elevated pulmonary vascular resistance, there is a specific group that does well after operation.     

Extravascular lung water in children immediately after operative closure of either isolated atrial septal defect or ventricular septal defect

Extravascular lung water (EVLW) was measured in 16 patients with congenital heart disease by the cold green dye, double indicator dilution technique. Five patients with optimally corrected tetralogy of Fallot served as controls, and EVLW in this group was 4.7 +/- 0.5 ml/kg (111 +/- 13 ml/m2) (mean +/- standard deviation). In 5 asymptomatic patients with atrial septal defect (ASD), normal pulmonary artery (PA) pressure and increased pulmonary blood flow, EVLW was 5.7 +/- 2.8 ml/kg (132 +/- 63 ml/m2), which was not significantly different from the value of control patients. However, in 6 patients with ventricular septal defect, PA hypertension, normal left atrial pressure and an equivalent left-to-right shunt to ASD patients, EVLW was 15.9 +/- 3.8 ml/kg (270 +/- 60 ml/m2). This was significantly different from values in both control and ASD patients (p less than 0.01). It is concluded that in the face of normal pulmonary vascular resistance, PA pressure is transmitted to the microvasculature, causing hydrostatic pulmonary edema. Other factors that may be implicated in the pathogenesis of pulmonary edema, such as increased pulmonary blood flow and relative lymphatic insufficiency in infants, cannot be excluded.     

Acute haemodynamic effects of nifedipine in patients with ventricular septal defect.

The haemodynamic effects of nifedipine were studied in 14 patients (aged 8-14 years, seven male and seven female) with ventricular septal defect with and without pulmonary hypertension. All underwent left and right heart catheterisation. In each patient the pressures and heart rate were measured and blood samples were taken for oximetry before and after sublingual administration of 10 mg nifedipine. In eight patients with ventricular septal defect without pulmonary hypertension (mean pulmonary artery pressure less than 20 mm Hg) nifedipine significantly reduced the mean aortic pressure and systemic vascular resistance, and significantly increased heart rate. The other haemodynamic indices did not change significantly. In six patients with ventricular septal defect complicated by pulmonary hypertension (mean pulmonary artery pressure greater than 20 mm Hg) nifedipine significantly increased systemic output, stroke volume, and heart rate, and significantly reduced systemic vascular resistance and the pulmonary to systemic flow ratio. The other haemodynamic indices did not change significantly. Nifedipine had a beneficial effect in patients with ventricular septal defect complicated by pulmonary hypertension. It reduced the left to right shunt and increased the stroke volume. This effect was not seen in patients with ventricular septal defect uncomplicated by pulmonary hypertension.