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1.
BACKGROUND: Magnetic resonance angiography (MRA) using segmented k-space fast low-angle shot imaging has recently been used to demonstrate the proximal coronary arteries in healthy subjects and in patients with coronary artery disease. We assessed the sensitivity and specificity of coronary MRA in heart transplant recipients and investigated the feasibility of coronary MRA in patients with metallic sutures and clips in the chest. MATERIALS AND METHODS: Sixteen cardiac transplant patients aged 57.2 +/- 7.9 years (mean +/- SD) were recruited. Forty-eight arterial segments were evaluated, including the left main artery (LMA), left anterior descending artery (LADA) and right coronary artery (RCA). We excluded the left circumflex artery which could not be imaged accurately. The average time between heart transplant operation and MRA was 6 years, whereas that between MRA and X-ray angiography was 4 months. The coronary MRA was interpreted by two experienced investigators who were blinded to the coronary X-ray angiography results. Similarly, the coronary X-ray angiography results were interpreted by two experienced investigators blinded to the MRA results. The coronary arterial segments were classified by MRA as being normal or as having an amount of disease that was significant (> 50% lesion) or insignificant (< 50% lesion). RESULTS: There were 28 true-negative, five true-positive, four false-negative and six false-positive results. Of the 28 true-negative cases, 13 were in the LMA, six in the LADA and nine in the RCA. There was one false-positive LMA, two false-positive LADA and three false-positive RCA stenoses. There were four false-negative results in the LADA and one in the RCA. Clips precluded evaluation in one LMA, one LADA and one RCA. One LMA and one LADA were not evaluated as a result of poor images. One false-positive RCA stenosis was caused by a metallic clip. Three of the false-negative LADA stenoses had lesions in the distal third of the artery. The sensitivity, specificity, negative and positive predictive values were generally poor for the left coronary artery. The best results were for the RCA (sensitivity 100%, specificity 75%, positive predictive value 50% and negative predictive value 100%). The specificity in the left coronary arteries (LMA and LADA) was 86%, but the other indicators were all poorer. For the RCA, LMA and LADA combined, the overall sensitivity was 56%, specificity 82%, predictive accuracy 45% and negative predictive value 88%. In three patients, < 50% RCA lesions were seen in the MRA data, which were all confirmed by angiography. No < 50% lesions were seen in the LMA or in the LADA by MRA or by X-ray angiography. CONCLUSION: Coronary MRA using the segmented fast low-angle shot technique is feasible in heart transplant recipients but the sensitivity and specificity of this method are limited. Further developments in coil design, rapid imaging techniques and respiratory monitoring methods are necessary to improve the accuracy of coronary MRA.  相似文献   

2.
Using an adapted two-dimensional spatially selective RF excitation scheme, a novel yet practical three-dimensional (3D) zonal echo-planar imaging technique for MR coronary angiography has been developed. The robustness of the technique compared with the two-dimensional (2D) segmented fast low angle shot (FLASH) method was evaluated using the right coronary artery images of 16 asymptomatic volunteers with a 0.5-T mobile scanner. Each 3D acquisition required multiple breath-holds, and real-time navigator echoes were used to ensure consistent breath-holding. Advantages of the technique include an improved signal-to-noise ratio, clearer depiction of tortuous coronary vessels due to decreased partial volume effects, and reduced motion blurring by the use of a short echo-planar readout.  相似文献   

3.
Until recently, direct measurements of coronary blood flow in fishes had not been made. This review presents and compares in vivo measurements of coronary flow recorded from the school shark, Galeorhinus australis, and the coho salmon, Oncorhynchus kisutch. In both species, the coronary blood flow was phasic and strongly influenced by the cardiac cycle. Coronary blood flow in the school shark was more severely compromised by the cardiac cycle with a short retrograde flow occurring during systole. In the coho salmon, there was an anterograde coronary blood flow throughout the cardiac cycle. Differences in coronary hemodynamics are discussed in relation to differences in the myoarchitecture of the school shark and coho salmon hearts. The regulation of coronary blood flow through changes in vascular resistance (vasoactivity of the coronary vessels) is also discussed.  相似文献   

4.
MT Massie  MJ Rohrer  JA Leppo  BS Cutler 《Canadian Metallurgical Quarterly》1997,25(6):975-82; discussion 982-3
PURPOSE: Because dipyridamole thallium (DT) scanning is a useful predictor of perioperative cardiac events, a positive results of a DT scan is frequently the basis for performing more invasive cardiac evaluation and for consideration for performing coronary revascularization procedures before performing peripheral vascular surgery. The rationale for this approach has been that the treatment of anatomically significant coronary artery disease would lower the risk of performing a subsequent vascular operation. However, the benefit of performing aggressive diagnostic and therapeutic cardiac procedures in such patients remains unproved. To examine this issue, data from patients who underwent coronary angiography because of thallium redistribution were compared with data from matched control subjects who underwent peripheral vascular operations without further cardiac evaluation. METHODS: The medical records of 70 consecutive patients who underwent coronary angiography because of the presence of two or more segments of redistribution on DT scan were reviewed and compared with 70 other patients matched with respect to age, gender, peripheral vascular operation, and number of segments of redistribution on DT scan who did not undergo additional cardiac evaluation. RESULTS: DT scans were performed on 934 preoperative peripheral vascular surgery patients to help in the assessment of operative risk. Ischemic responses, defined as two or more segments of redistribution, were observed in 297. Of these, 70 underwent cardiac catheterization and 25 underwent coronary revascularization procedures. Adverse outcomes affected 46% of the coronary angiography group and 44% of the control group (p = NS). Patients who underwent coronary angiography and were considered for myocardial revascularization had fewer cardiac events with a subsequent vascular operation than did the control subjects. However, any possible benefit from invasive cardiac evaluation was offset by the three deaths and two myocardial infarctions (MIs) that complicated the cardiac evaluation. There was no significant difference between the angiography group and the matched control subjects with respect to perioperative nonfatal MI (13% vs 9%), fatal MI (4% vs 3%), late nonfatal MI (16% vs 19%), or late cardiac death (10% vs 13%). In long-term follow-up, MIs occurred later in patients who underwent coronary angiography than the control subjects (p = 0.049), but this difference was not associated with an improvement in the overall survival rate. CONCLUSIONS: The risks of extended cardiac evaluation and treatment did not produce any improvement in either the perioperative or the long-term survival rate. For most vascular surgery patients who have a positive result of a DT scan, coronary angiography does not provide any additional useful information.  相似文献   

5.
A successful case of emergency coronary artery bypass grafting for a 69-year-old man with refractory cardiac arrest due to impending myocardial infarction was reported. Preoperative full resuscitation including external cardiac massage was required. The duration from cardiac arrest to cardiopulmonary bypass establishment was 24 minutes and aortic cross clamping time was 29 minutes for triple bypass grafting to the right, left circumflex and left anterior descending coronary artery.  相似文献   

6.
The case of a three year-old child with anomalous origin of the left coronary artery from the pulmonary artery is presented. He had a clinical picture and an electrocardiographic pattern of antero-lateral myocardial infarction that suggested a cardiac malformation. Once the diagnosis was established by cardiac catheterization and coronary arteriography, the defect was successfully correted by transplanting the anomalous coronary vessel to the aorta. The clinical, electrocardiographic and angiographic features of the anomaly are given.  相似文献   

7.
The present study was designed to assess cardiac autonomic activities, coronary microvascular function, and their relationship in patients with syndrome X. Control of coronary blood flow is complex, and impaired coronary flow reserve has been attributed as the cause of myocardial ischemia in patients with syndrome X. It is unknown whether cardiac autonomic activities are altered in the presence of coronary microvascular dysfunction in patients with syndrome X. Eighteen patients with syndrome X were studied. Great cardiac vein flow was measured by the thermodilution method and the coronary flow reserve was determined by intravenous dipyridamole (0.56 mg/kg) infusion. Twenty-four-hour ambulatory electrocardiograms were obtained in a drug-free state. Another 14 age- and sex-matched normal subjects served as a control group. The amplitude (in ms) of ultralow (ULF), very-low (VLF), low (LF), and high (HF) frequency bands and total spectra of heart rate variability were measured for twenty-four-hour and every four-hour interval of the day.  相似文献   

8.
BACKGROUND: Accelerated coronary arteriosclerosis is a major complication in long-term survivors of cardiac transplantation. Estrogen prevents transplant arteriosclerosis in experimental cardiac and aortic allografts and may act by an immune mechanism. METHODS AND RESULTS: New Zealand White rabbits immunosuppressed with cyclosporine were recipients of cardiac allografts from Dutch Belted rabbits. The recipients received either estradiol or placebo daily until they were killed 6 weeks later. Histological cross sections of the cardiac allograft were used for quantification of major histocompatibility complex (MHC) class II antigen expression, T lymphocytes, and macrophages by immunohistochemistry using monoclonal antibodies. MHC class II antigen expression was not detectable in allograft coronary arteries from any of the estradiol-treated recipients, whereas this antigen expression was present in the allograft coronary arteries from all the placebo-treated recipients. Macrophage and lymphocyte infiltration of the allograft coronary artery myointima was significantly less frequent in the estradiol-treated group. Rejection was moderate but slightly less in the estradiol-treated group. These findings were associated with a 60% decrease in allograft coronary artery myointimal thickening (determined by morphometry) in the estradiol-treated compared with the placebo-treated group. CONCLUSIONS: Estradiol treatment of cardiac allograft recipients abolishes MHC class II antigen expression in the coronary arteries and decreases macrophage infiltration in all three layers of the vessel wall, whereas T-lymphocyte infiltration is decreased only in the myointima. These findings are associated with estradiol inhibition of myointimal proliferation. Thus, estradiol treatment may have a beneficial effect on graft arteriosclerosis through immune mechanisms.  相似文献   

9.
Spontaneous coronary artery rupture resulted in cardiac tamponade in a man with Ehlers-Danlos syndrome (type IV) presenting with acute onset of cardiac chest pain. Electrocardiograms suggested acute myocardial infarction. The haemopericardium was drained and angiography showed a ruptured distal branch of the left circumflex coronary artery. The patient remains well.  相似文献   

10.
Results of studies have suggested that endotoxin and lowered coronary arterial perfusion pressures are detrimental to cardiac performance and lead to failure. Prevention of cardiac failure in the isolated canine heart preparation confronted with endotoxin and decreased coronary perfusion pressure was possible by perfusing these hearts with sodium nitroprusside. Prevention of failure was manifested by a lowered left ventricular endiastolic pressure and was associated with increased coronary flow and decreased coronary resistance with increased oxygen delivery and decreased oxygen extraction. Possible explanations for improved performance by dilator perfusion include increased delivery of oxygen and nutrients to myocardial tissue as well as a reduction of ventricular wall tension by dilating the coronary vascular skeleton. Prevention of extravasation of interstitial fluid into myocardial tissue by reducing overperfusion of potentially damaged coronary vessels could serve to maintain myocardial integrity and ventricular compliance. The potential use of such therapy warrants further study, with emphasis on evaluating the hemodynamics of the intact animal.  相似文献   

11.
The purpose of this study was to determine the feasibility of measuring partial pressure of oxygen (pO2), partial pressure of carbon dioxide (pCO2), and pH in cardiac lymph and to evaluate the relationship of these parameters to comparable measurements in arterial and coronary sinus blood in the normal heart under various respiratory conditions. In four anesthetized open-chest dogs, the principal cardiac lymphatic as well as the femoral artery and coronary sinus were cannulated. Ventilation was varied by changing oxygen concentration, tidal volume, and respiratory rate. PO2, pCO2, and pH were measured in the cardiac lymph, arterial blood, and coronary sinus blood after each change in ventilation. For pH and pCO2, good correlations were observed between the arterial blood and cardiac lymph, arterial blood and coronary sinus blood, and coronary sinus blood and cardiac lymph. The correlation between the pO2 measured in the arterial blood and the pO2 measured in the cardiac lymph was not as strong, and this may have been related to difficulty achieving a steady state. Gas tensions (pO2, pCO2, and pH) can be measured in cardiac lymph and may provide a window to the interstitial compartment of the heart. This is an additional tool for the laboratory study of ischemia and other forms of heart disease.  相似文献   

12.
BACKGROUND: Although residual myocardial viability in patients with coronary artery disease and extensive regional asynergy is associated with improved ventricular function after coronary bypass surgery, the relationship between viability and clinical outcome after surgery is unclear. We hypothesized that patients with poor ventricular function and predominantly viable myocardium have a better outcome after bypass surgery compared with those with less viability. METHODS AND RESULTS: Seventy patients with multivessel coronary artery disease and left ventricular ejection fractions < 40% who underwent preoperative quantitative 201Tl scintigraphy before coronary bypass surgery were analyzed retrospectively. 201Tl scintigrams were reviewed blindly, and each segment was assigned a score based on defect magnitude. Segmental viability scores were summed and divided by the number of segments visualized to determine a viability index. The viability index was significantly related to 3-year survival free of cardiac event (cardiac death or heart transplant) after bypass surgery (P=.011) and was independent of age, ejection fraction, and number of diseased coronary vessels. Patients with greater viability (group 1; viability index > 0.67; n=33) were similar to patients with less viability (group 2; viability index < or = 0.67; n=37) with respect to age, comorbidities, and extent of coronary artery disease. There were 6 cardiac deaths and no heart transplants in group 1 patients and 15 cardiac deaths and two transplants in group 2 patients. Survival free of cardiac death or transplantation was significantly better in group 1 patients on Kaplan-Meier analysis (P=.018). CONCLUSIONS: We conclude that resting 201Tl scintigraphy may be useful in preoperative risk stratification for identification of patients more likely to benefit from surgical revascularization.  相似文献   

13.
OBJECTIVE: This study was undertaken to determine the impact of previous cardiac surgery on the presentation, management, and outcome of late dissection of the ascending aorta. PATIENTS AND METHODS: From 1976 to 1998, type A dissection developed in 56 patients with a history of previous cardiac surgery. Interval from first operation to type A dissection was 49 +/- 47 months (0.3-180 months). Previous operations were coronary artery bypass grafting (n = 40), aortic valve replacement (n = 8), and other (n = 8). RESULTS: Type A dissection was acute in 34 patients and chronic in 22. In acute dissection, aortic insufficiency occurred in 50%, malperfusion in 12%, and rupture in 18%; 2 patients (6%) were in hemodynamically unstable condition because of rupture. Of patients with previous coronary bypass grafting, 98% had preoperative coronary angiography. Type A dissection was treated by supracoronary tube graft (84%), Bentall procedure (14%), or local repair (2%). Strategies for managing previous coronary bypass grafting included reimplantation of proximal anastomoses with a button of native aorta (29 patients), interposition graft to pre-existing saphenous vein grafts (9 patients), and new saphenous vein grafts (20 patients). Eight hospital deaths occurred (14%). CONCLUSIONS: We conclude that (1) patients having type A dissection late after cardiac surgery infrequently have cardiac tamponade and hemodynamic collapse; (2) patients with previous coronary bypass grafting require coronary angiography, because operative management must account for pre-existing coronary artery disease; and (3) operative mortality is low, and this may be attributable to preoperative hemodynamic stability, delineation of coronary anatomy in those with previous coronary bypass grafting, and operative treatment of coronary artery disease.  相似文献   

14.
OBJECTIVES:This study sought to assess the long-term prognostic utility of dobutamine stress echocardiography in predicting fatal and nonfatal cardiac events. BACKGROUND: Although dobutamine stress echocardiography has improved sensitivity and specificity for detection of coronary artery disease, little is known of its predictive value for long-term cardiac events. Therefore, we followed up 120 consecutive patients who underwent dobutamine echocardiography for suspected coronary disease from March 1989 to August 1991. METHODS: All patients presenting for coronary angiography for chest pain were eligible for recruitment. Follow-up was 100% complete at 5 years (range 3.0 to 6.1). Cardiac events were defined as cardiac death or nonfatal myocardial infarction or the need for coronary revascularization (coronary angioplasty or bypass surgery). RESULTS: Positive (n = 78) and negative (n = 42) dobutamine test groups differed in their rates of coronary artery bypass graft surgery (37.2% vs. 9.5%, p < 0.001, respectively) and mortality. Of 26 total deaths, 22 occurred in the group with positive dobutamine test results (28% vs. 9.5%, p < 0.018); all 7 cardiac deaths occurred in this group as well (9% vs. 0%, p < 0.045). By multivariate regression analysis, positive results on dobutamine echocardiography remained independently predictive of future cardiac death after left ventricular ejection fraction and other clinical variables were accounted for. CONCLUSIONS: A positive finding on dobutamine echocardiography is an independent predictor of long-term cardiac mortality, whereas a negative finding confers a significantly reduced likelihood of cardiac death as much as 5 years from initial testing. We conclude that dobutamine stress echocardiography can be used to predict which patients with suspected coronary artery disease are at low risk for cardiac death and do not require concurrent nuclear or invasive testing.  相似文献   

15.
The extent to which a preference for less aggressive care explains the lower rate of invasive cardiac services for women and African-Americans is unknown. A prospective observational study of 272 patients admitted to the coronary care unit was conducted at a tertiary referral teaching hospital and a community teaching hospital. In stepwise multivariate analysis, having less than a college education, poor cardiac function, not having undergone a previous cardiac catheterization, being a patient in a nonreferral community hospital, and current smoking were positively associated with a patient's stating that he or she would disagree with a physician's recommendation for a cardiac catheterization. The step-wise multivariate model with cardiac catheterization as the dependent variable indicated that being a patient in a referral medical center, patient willingness to accept a physician's recommendation for a cardiac catheterization, severe heart disease, and having attended high school were predictive. Women did not differ from men in their preference for or receipt of cardiac catheterization. Patients in the coronary care unit with lower levels of education were less likely to undergo cardiac catheterization. This association was only partly explained by less educated patients' being less willing to accept a physician's recommendation to undergo cardiac catheterization.  相似文献   

16.
BACKGROUND: The role of coronary spasm in underlying disease-free patients who were resuscitated from sudden cardiac arrest remained uncertain. This study investigated the cause of cardiac arrest, and the etiologic and prognostic differences were compared between patients with underlying heart disease (group I) and those patients without underlying heart disease (group II). METHODS: Twenty-five survivors of sudden cardiac arrest were classified into two groups according to the presence or absence of underlying heart disease. To investigate the cause of cardiac arrest, we performed ergonovine testing and electrophysiologic study. Fifteen of the patients had underlying heart disease, while 10 did not. RESULTS: Electrophysiologic abnormalities were found in 13 of the 15 patients in group I. In group II, spontaneous attack of coronary spasm occurred in four patients during the observation period, and coronary spasm was induced in three of the remaining six period of 32 +/- 23 months, whereas no patients in group II had recurrence of sudden cardiac arrest at a median follow-up of 32 months (range, 10 to 72 months). CONCLUSIONS: Electrophysiologic study identified a potential cause in 13 of 15 patients with underlying heart disease. Coronary spasm was involved in the pathogenesis of sudden cardiac arrest in survivors without identifiable underlying heart disease.  相似文献   

17.
ML Ong 《Canadian Metallurgical Quarterly》1993,70(3):276-7; discussion 277-8
A 17 year old girl with a congenital right coronary artery to coronary sinus fistula presented with recurrent septic pulmonary embolism secondary to tricuspid valve endocarditis. The diagnosis was made on the basis of echocardiography and cardiac angiography.  相似文献   

18.
PURPOSE: This study evaluated the value of preoperative cardiac screening with dipyridamole thallium scintigraphy and radionuclide ventriculography in vascular surgery patients. METHODS: From July 1, 1989, to Dec. 31, 1991, we routinely (irrespective of the patient's cardiac history or symptomatology) performed dipyridamole thallium scintigraphy (DTS) and radionuclide ventriculography (RVG) in 394 patients being considered for an elective vascular operation. Patients with reversible defects on DTS underwent coronary arteriography. RESULTS: DTS results were normal in 146 patients (37%), showed a fixed defect in 75 (19%), and showed a reversible defect in 173 (44%). Patients with and without a history of angina or myocardial infarction had identical rates of reversible defects. Normal left ventricular function (> 50%) was noted in 76% of the patients; 17% had moderate dysfunction (35% to 50%) and 7% had a low ejection fraction (< 35%). The finding of severe coronary artery disease led to cardiac revascularization in 17 patients who had no prior history of cardiac disease and in 13 patients with a history of angina or myocardial infarction. Two deaths and nine major complications were associated with coronary arteriography and cardiac revascularization. Vascular procedures (144 aortic, 53 carotid, 146 infrainguinal) were ultimately performed in 343 patients, with a mortality rate of 1.7% (3.5% aortic, 0% carotid, and 0.7% infrainguinal bypass). The nonfatal perioperative myocardial infarction rate was 2.0%. We monitored all 394 patients for cardiovascular events, with a mean follow-up of 40 months. Patients who underwent cardiac revascularization had a 4-year survival rate of 75%, which was similar to those with a normal DTS. Late cardiac events were significantly more frequent in patients who had either a reversible DTS or RVG < 35%. CONCLUSIONS: Routine cardiac screening of vascular surgery patients had similar impact on patients irrespective of their prior history or current symptoms suggesting coronary artery disease. Routine screening did not result in substantial benefit. Screening studies such as DTS or RVG may be most useful as part of an overall risk versus benefit assessment in patients without active symptoms of coronary artery disease who have less compelling indications for vascular intervention (claudication, moderate-sized aortic aneurysms, or asymptomatic carotid disease).  相似文献   

19.
OBJECTIVE AND BACKGROUND: Orthotopic liver transplantation is both a difficult and a demanding surgical procedure. It is not unexpected that cardiovascular dysfunction is present in some individuals being evaluated for liver transplantation. Thus, all potential liver transplant recipients seen at this center undergo a full cardiac evaluation prior to being accepted for transplantation. The goal of this report was to review the components of the cardiovascular evaluation utilized at the Oklahoma Transplantation Institute and to determine their overall usefulness as well as the ability of the process to identify individuals at high risk for a cardiac misadventure during liver transplantation. MATERIALS AND METHODS: Between June 25, 1993 and June 30, 1995, a total of 154 consecutive patients with chronic liver disease were evaluated. The primary liver disease of each was established utilizing specific serologic and biochemical tests, ultrasonographic and abdominal tomographic findings, as well as hepatic histology results and hepatic iron and copper level determinations. Each liver transplant candidate underwent a full cardiac evaluation consisting of the following: nuclear ventriculography to estimate the left ventricular ejection fraction (at rest and during exercise), right ventricular ejection fraction, cardiac output, stroke volume and cardiac index; uptake images using thallium and adenosine to identify foci of cardiac ischemic or fixed defects; echocardiography to define the dimensions of the various cardiac chambers, wall thicknesses, cardiac contractility and morphology of the cardiac valves. Finally, coronary arteriography was performed in 26 patients (16.9%) who were suspected of having clinically important coronary artery disease. It should be noted that all of the cardiac evaluations were performed by a single cardiologist. RESULTS: Eight of the 154 potential liver transplant candidates (5.2%) were determined as not being eligible for liver transplantation because of an inadequate cardiac status based upon an initial history and physical examination. Forty-one of the remaining 146 patients (28.1%) underwent liver transplantation. The remaining 105 subjects have not been transplanted for reasons not related to the cardiac status. Eight of the 41 (19.5%) transplanted patients had a clinically advanced cardiac problem recognized prior to liver transplantation. Four of these eight required a specific cardiac intervention prior to liver transplantation consisting of coronary bypass surgery (n = 1), coronary artery balloon dilation (n = 2) or pericardiectomy (n = 1). The remaining four patients required no pretransplant cardiac intervention and were transplanted. None of these experienced any cardiac complications during, or in the 3 months following, the liver transplant procedure. Only one patient experienced a specific postoperative cardiac complication, consisting of an episode of high grave A-V block requiring transplant placement of a cardiac pacing device. This patient had hemochromatosis. CONCLUSIONS: Based upon this experience, it can be concluded that coronary artery disease per se is not an absolute contraindication for liver transplantation. With appropriate treatment, liver transplantation can be performed safely in individuals with confounding cardiac disease. Nuclear ventriculography and echocardiography are essential procedures in evaluating potential liver transplant recipients in an effort to exclude those with occult cardiomyopathy. Coronary arteriography is indicated only in selected cases with evidence of cardiac ischemia or infarction.  相似文献   

20.
A 61-yr-old woman was referred to our hospital for evaluation of a suspected right atrial myxoma. The transesophageal echocardiogram suggested the presence of an anomalous right coronary artery with fistulous connection to the coronary sinus. At cardiac catheterization, an oxygen step-up in the right atrium indicated a 1.3:1.0 left-to-right shunt. Aortic root angiography showed a large and calcified right coronary artery cirsoid draining to the coronary sinus, which appeared remarkably dilated. In this rare anomaly, cardiac catheterization is necessary, not only to quantify the magnitude of the left-to-right shunt, which is an important requirement for the indication to surgical treatment, but also to confirm the echocardiographic diagnosis.  相似文献   

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