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BACKGROUND Interatrial septum (IAS) dissection due to transseptal puncture (TSP) is a rare, underreported complication of the procedure. Data on the mechanism, diagnosis, and management of this complication are lacking. METHODS We conducted a systematic review of all reported cases of IAS dissection with or without associated LA hematoma due to TSP, by thoroughly searching MEDLINE and EMBASE through May 2019. RESULTS After screening of n = 882 studies, eight studies with a total of 19 patients addressed the complication of IAS dissection and/or LA hematoma secondary to TSP. Median age was 63 years with a 1:1 male to female ratio. Ablation of atrial fibrillation was the most frequently reported procedure (84%). Diagnosis was established using fluoroscopy with contrast injection (58%), TEE (32%) or intracardiac echocardiography (5%). The mechanism identified involved puncture of the septum secundum portion of the IAS, leading to transient needle passage into the extracardiac space. In the majority of patients, the hematoma remained localized in the IAS and management was conservative with progressive resolution of the hematoma during follow-up (95%). Two patients (11%) required further intervention by either pericardiocentesis or surgical drainage due to hemodynamic instability. CONCLUSIONS IAS dissection with or without hematoma after TSP remains an underdiagnosed entity. The main mechanism involves lesion to the septum secundum portion of the IAS, resulting in needle passage into the extracardiac space and local bleeding. Although conservative management may be sufficient in the majority of cases, interventional cardiologists should be familiar with this complication and its diagnosis.

In this paper, we describe the clinical presentation of 2 patients with atypical Takotsubo syndrome recently observed in our hospital. It is the occasion de review the clinical characteristics, the biological markers, the imaging clues as well as the diagnosis criteria, the treatment algorithm and the prognostic of this disease, first described 30 years ago by our Japanese colleagues. The current knowledge of this recently summarized entity in an international expert consensus document is the main reference of this presentation.Dans cet article, nous décrivons 2 cas de présentation atypique d’un syndrome de Takotsubo survenus récemment à l’hôpital de Morges. C’est l’occasion de revoir le tableau clinique, la démarche diagnostique, les caractéristiques biologiques et d’imagerie, le traitement et le pronostic de cette affection décrite pour la première fois il y a 30 ans par nos collègues japonais. Nous nous sommes basés en particulier sur un document de consensus d’experts internationaux qui rassemblent toutes les connaissances actuelles sur cette affection.

AIMS To evaluate the very long-term risk of recurrent thromboembolic events in patients treated by percutaneous PFO closure. METHODS AND RESULTS Between 1998 and 2008, a total of 232 consecutive patients with PFO and a high suspicion of paradoxical embolism were treated by percutaneous closure. The following major events were observed during hospitalisation: implantation failure (one patient) and appearance of an acute left-sided device thrombus requiring surgery (one patient). The primary endpoint of the study was a recurrent embolic event beyond at least five years' follow-up. During a mean follow-up of 7.6±2.4 years, this event occurred in five patients, representing a 0.28% annual/patient risk. Other major complications during follow-up were the following: late thrombus formation on the device (two patients) and transient atrial fibrillation (15 patients). Three patients died during follow-up from cardiovascular causes considered not related to the index procedure. The PFO was judged closed on follow-up echocardiography in 92.3% of patients. CONCLUSIONS Long-term follow-up following percutaneous PFO closure for presumed paradoxical embolism reveals very low recurrence rates. This observation should be put in perspective with recent published randomised trials comparing percutaneous closure and medical therapy.

An 89-year-old man presented with global cardiac insufficiency 4 years after mitral valve replacement by a 29 mm St Jude mechanical valve for severe mitral insufficiency. In the immediate post-operative period, a mild paravalvular leak had been noted and increased progressively from 0.13 to 0.38 cm2 actually ( Panel A ). Because of the very active status of the …

Mitral regurgitation (MR) is the most frequent valvular disease in industrialised countries. MR is classified as primary (mostly degenerative with valve prolapse) or secondary (mainly due to underlying ischemic heart disease resulting in deformation of the valve structure). Surgical repair represents the optimal treatment for severe primary MR, whereas the benefits of surgical correction of secondary MR are controversial. Over the past few years, transcatheter techniques have been developed to treat MR, such as the percutaneous edge-to-edge procedure (MitraClip). These approaches represent a novel therapeutic choice for patients judged inoperable by the "heart team". This review article aims to summarize the principles of MR assessment and discuss current therapeutic options for severe MR, taking into account the latest advances in the field.

The perioperative treatment of patients on dual antiplatelet therapy after myocardial infarction, cerebrovascular event or coronary stent implantation represents an increasingly frequent issue for urologists and anesthesiologists. We assess the current scientific evidence and propose strategies concerning treatment of these patients.A MEDLINE and PubMed search was conducted for articles related to antiplatelet therapy after myocardial infarction, coronary stents and cerebrovascular events, as well as the use of aspirin and/or clopidogrel in the context of surgery.Early discontinuation of antiplatelet therapy for secondary prevention is associated with a high risk of coronary thrombosis, which is further increased by the hypercoagulable state induced by surgery. Aspirin has recently been recommended as a lifelong therapy. Clopidogrel is mandatory for 6 weeks after myocardial infarction and bare metal stents, and for 12 months after drug-eluting stents. Surgery must be postponed beyond these waiting periods or performed with patients receiving dual antiplatelet therapy because withdrawal therapy increases 5 to 10 times the risk of postoperative myocardial infarction, stent thrombosis or death. The shorter the waiting period between revascularization and surgery the greater the risk of adverse cardiac events. The risk of surgical hemorrhage is increased approximately 20% by aspirin and 50% by clopidogrel.The risk of coronary thrombosis when antiplatelet agents are withdrawn before surgery is generally higher than the risk of surgical hemorrhage when antiplatelet agents are maintained. However, this issue has not yet been sufficiently evaluated in urological patients and in many instances during urological surgery the risk of bleeding can be dangerous. A thorough dialogue among surgeon, cardiologist and anesthesiologist is essential to determine all risk factors and define the best possible strategy for each patient.

Recent clinical data show that the risk of coronary thrombosis after antiplatelet drugs withdrawal is much higher than that of surgical bleeding if they are continued. In secondary prevention, aspirin is a lifelong therapy and should never be stopped. Clopidogrel is regarded as mandatory until the coronary stents are fully endothelialized, which takes 3 months for bare metal stents, but up to 1 yr for drug-eluting stents. Therefore, interruption of antiplatelet therapy 10 days before surgery should be revised. After reviewing the data on the use of antiplatelet drugs in cardiology and in surgery, we propose an algorithm for the management of patients, based on the risk of myocardial ischaemia and death compared with that of bleeding, for different types of surgery. Even if large prospective studies with a high degree of evidence are still lacking on different antiplatelet regimens during non-cardiac surgery, we propose that, apart from low coronary risk situations, patients on antiplatelet drugs should continue their treatment throughout surgery, except when bleeding might occur in a closed space. A therapeutic bridge with shorter-acting antiplatelet drugs may be considered.

Performing a surgical procedure on a patient undergoing anti-platelet therapy raises a dilemma: is it safer to withdraw the drugs and reduce the haemorrhagic risk, or to maintain them and reduce the risk of myocardial ischaemic events? Based on recent clinical data, this review concludes that the risk of coronary thrombosis on anti-platelet drugs withdrawal is much higher than the risk of surgical bleeding when maintaining them. In secondary prevention, aspirin is a lifelong therapy and should never be stopped. Clopidogrel is mandatory as long as the coronary stents are not fully endothelialized, which takes 6-24 weeks depending on the technique used, but might be required for a longer period.

INTRODUCTION: Tropheryma whipplei infection should be considered in patients with suspected infective endocarditis with negative blood cultures. The case (i) shows how previous symptoms can contribute to the diagnosis of this illness, and (ii) elucidates current recommended diagnostic and therapeutic approaches to Whipple's disease. CASE PRESENTATION: A 71-year-old Swiss man with a past history of 2 years of diffuse arthralgia was admitted for a possible endocarditis with severe aortic and mitral regurgitation. Serial blood cultures were negative. Our patient underwent replacement of his aortic and mitral valve by biological prostheses. T. whipplei was documented by polymerase chain reactions on both removed valves and on stools, as well as by valve histology. A combination of hydroxychloroquine and doxycycline was initiated as lifetime treatment followed by the complete disappearance of his arthralgia. CONCLUSIONS: This case report underlines the importance of considering T. whipplei as a possible causal etiology of blood culture-negative endocarditis. Lifelong antibiotic treatment should be considered for this pathogen (i) due to the significant rate of relapses, and (ii) to the risk of reinfection with another strain since these patients likely have some genetic predisposition.

In this report we present the case of a 77-yr-old man who underwent resection of the upper lobe of the left lung for a carcinoma, six weeks after percutaneous transluminal coronary angioplasty (PTCA) with stenting of the left anterior descending (LAD) and circumflex coronary arteries. Antiplatelet therapy with clopidogrel was interrupted two weeks before surgery to allow for epidural catheter placement and to minimize haemorrhage. The surgical procedure was uneventful. In the immediate postoperative period, however, the patient suffered severe myocardial ischaemia. Emergency coronary angiography showed complete thrombotic occlusion of the LAD stent. In spite of successful recanalization, reinfarction occurred and the patient died in cardiogenic shock. Prophylactic preoperative coronary stenting may put the patient at risk of stent thrombosis if surgery cannot be postponed for three months. In such cases, other strategies such as perioperative β-blockade for preoperative cardiac management should be considered. Br J Anaesth 2004; 92: 743-7

BACKGROUND: The excellent results of the Maze III operation have demonstrated that a surgical cure of atrial fibrillation (AF) is possible. A simplified Maze procedure with radiofrequency (RF)ablation of the atrial tissue added to open heart surgery may help to cure chronic AF with low risk. METHODS: From May 1998 to March 2001, an RF left atrial compartmentalization concomitant to a cardiac surgical intervention was performed on 40 of 1,258 patients (3.2 %). Thirty-seven patients had mitral valve disease, two had aortic valve disease and one had coronary artery disease. All patients presented with chronic refractory AF for a mean time of 40.4 months ranging from 4 months to 18 years. RESULTS: Mitral valve replacement (MVR) was performed in 19 patients, mitral valve repair in 12, combined aortic and mitral valve procedures were performed in 6, aortic valve replacement(AVR) in 2 and CABG in 1 patient. Cardiopulmonary bypass time for the complete procedure was 138 +/- 32 minutes with an ablation time of 19 +/- 5 minutes. No complication related to RF application was noted. Sinus rhythm was present in 68% after 12.5 +/- 8.5 months. CONCLUSIONS: RF left atrial compartmentalization combined with cardiac surgical interventions proved to be easy and safe to perform. The long-term results still have to be confirmed with further regular patient follow-up examinations.

Background —Exaggerated pulmonary hypertension is thought to play an important part in the pathogenesis of high-altitude pulmonary edema (HAPE). Endothelin-1 is a potent pulmonary vasoconstrictor peptide that also augments microvascular permeability. Methods and Results —We measured endothelin-1 plasma levels and pulmonary artery pressure in 16 mountaineers prone to HAPE and in 16 mountaineers resistant to this condition at low (580 m) and high (4559 m) altitudes. At high altitude, in mountaineers prone to HAPE, mean (±SE) endothelin-1 plasma levels were ≈33% higher than in HAPE-resistant mountaineers (22.2±1.1 versus 16.8±1.1 pg/mL, P r =0.82, P r =0.35, P =0.05). Conclusions —These findings suggest that in HAPE-susceptible mountaineers, an augmented release of the potent pulmonary vasoconstrictor peptide endothelin-1 and/or its reduced pulmonary clearance could represent one of the mechanisms contributing to exaggerated pulmonary hypertension at high altitude.

A 32-year-old woman was diagnosed at the age of 8 years with a third degree atrioventricular block for which a DDD pacemaker was implanted. She now presented with exertional fatigue and dyspnoea because of a pacemaker lead-induced isolated tricuspid valve stenosis (mean gradient was 4 mm Hg at rest and 19 mm Hg during exercise, measured valve area using planimetry was 1.2 cm2) (Figure 1A). She was successfully treated with balloon valvotomy of the tricuspid valve using a 30 mm Inoue balloon (Toray industries Inc.) (Figure 1B) after which the tricuspid valve area augmented from 1.2 to 2.4 cm2 (mean resting transvalvular gradient of 2 mm Hg at rest and 6 mm Hg during exercise) with only a mild tricuspid regurgitation (Figure 1C). The patient mentioned a dramatic symptomatic improvement during the weeks after the procedure. The most probable pathophysiological mechanism of this pacemaker lead-induced tricuspid stenosis is repeated whiplash injury by the lead leading to severe scarring of the valve with subsequent stenosis. To our knowledge, this is only the third case described of successful percutaneous balloon valvotomy for pacemaker lead-induced tricuspid stenosis.1 ,2 Most reported cases are treated surgically or conservatively.

BACKGROUND. Pulmonary hypertension is a hallmark of high-altitude pulmonary edema and may contribute to its pathogenesis. When administered by inhalation, nitric oxide, an endothelium-derived relaxing factor, attenuates the pulmonary vasoconstriction produced by short-term hypoxia. METHODS. We studied the effects of inhaled nitric oxide on pulmonary-artery pressure and arterial oxygenation in 18 mountaineers prone to high-altitude pulmonary edema and 18 mountaineers resistant to this condition in a high altitude laboratory (altitude, 4559 m). We also obtained lung-perfusion scans before and during nitric oxide inhalation to gain further insight into the mechanism of action of nitric oxide. RESULTS. In the high-altitude laboratory, subjects prone to high-altitude pulmonary edema had more pronounced pulmonary hypertension and hypoxemia than subjects resistant to high-altitude pulmonary edema. Arterial oxygen saturation was inversely related to the severity of pulmonary hypertension (r=-0.50, P=0.002). In subjects prone to high-altitude pulmonary edema, the inhalation of nitric oxide (40 ppm for 15 minutes) produced a decrease in mean (+/-SD) systolic pulmonary-artery pressure that was three times larger than the decrease in subjects resistant to such edema (25.9+/-8.9 vs. 8.7+/-4.8 mm Hg, P

Transthoracic dynamic 3-dimensional reconstruction of the heart with tissue depiction has been proved to be feasible when using various methods of data acquisition. The same method can theoretically be applied to color Doppler flows to generate dynamic 3-dimensional images of intracardiac blood flow jets. To explore the feasibility of this approach, we studied 41 patients with various valvular disorders or intracardiac shunts. We acquired sequential 2-dimensional images along with color Doppler information using rotational scanning from a transthoracic or a subcostal window. Images were digitized and processed for 3-dimensional reconstruction using dedicated software. After adequate segmentation, the flow jets were displayed in 3 dimensions in a gray scale format. With use of this approach, 3-dimensional reconstruction of color Doppler flows was possible in all but 1 patient. Still frames allowed immediate appreciation of the shape of the jets, their location in the cardiac chambers, and their size related to that cavity. Dynamic display was even more striking by showing the flow in real time. Dynamic 3-dimensional images enabled visualization of flow jets in projections not available in conventional color flow Doppler, looking directly at the views of shunt and regurgitant flows, and also permitted 3-dimensional delineation of flow convergence zones. We conclude that dynamic visualization of various intracardiac flows in 3 dimensions using transthoracic echocardiography is possible. It provides a better understanding of the shape and size of the jets, and can potentially aid in flow quantification by displaying the actual shape of flow convergence regions.

Objectives. This study attempted to determine the site, relative size and dynamioc geometry of atrial septal defects using dynamic three-dimensional echocardiography. Background. Recent studies have demonstrated the feasibility of dynamic three-dimensional echocardiography. Images are acquired from computerized reconstruction of sequential, tomographic ultrasound “slices” of the heart. Ultrasound images can be obtained by linear progression of a transducer within a transesophageal imaging probe. In small infants and children the large transducer size has not allowed transesophageal placement, and the probe has been place on the thorax or in the subcostal position. Other scaning devices, housed in plastic containers, acquire images in a rotational format and can also be placed in a transthoracic or subcostal position. Methods. Specially desiged transesophageal probes and a dedicated computer unit were used for two-dimensional image retrieval and reconstruction of three-dimensional images. Sixteen patients with atrial septal defects were studied (median age 18 months, range 1 day to 18 years). In the one patient, images were obtained by transesophageal probe placement; in the other 15 patients, the probe was placed in the transthoracic or subcostal position. Results. A dynamic three-dimensional echocardiogram of the atrial septal defect could be obtained in 13 of the 16 patients. The distinguishing features of the atrial septal defects and their spatial orientation could be visualized in unique three-dimensional views. Conclusions. Dynamic three-dimensional imaging could be applied to the specific evaluation of atrial septal defects. Unique views of the heart allowed for spatial comprehension of the defects, rendering potentially important clinical information.

Up to 30% of patients with chronic obstructive pulmonary disease (COPD) simultaneously suffer from often-unrecognised chronic heart failure (HF). Their timely identification is challenging as both conditions share similar clinical presentations.To assess the performance of BNP in detecting left ventricular systolic dysfunction in patients with no history of HF admitted for acute exacerbation of COPD in a regional second-care hospital.Retrospective medical records analysis of all patients hospitalised between January 2003 and May 2009 with the final diagnosis of acute exacerbation of COPD, and who had undergone BNP dosage at admission followed by an echocardiography.Among the 57 patients included, 13 had left ventricular systolic dysfunction. There was a statistically significant difference of mean BNP values between patients with or without systolic dysfunction (mean 689 pg/ml vs. 340 pg/ml, p = 0.007). For the detection of systolic dysfunction, a BNP level inferior to 100 pg/ml yielded a sensitivity of 92% and a negative predictive value of 91%, whereas BNP higher than 500 yielded a sensitivity of 80% and a positive predictive value of 47%. In a multivariate logistic regression analysis, a BNP value ≥500 (odds ratio 8.5, 95% confidence interval 1.9 to 38.2, p = 0.005) and history of coronary heart disease (odds ratio 5.9, 95% confidence interval 1.01 to 34.7, p = 0.048) remained as independent and mutually adjusted predictors of left ventricular systolic dysfunction.Our study confirms that BNP can help physicians in identifying heart failure in patients suffering from an acute exacerbation of COPD.

Aspirin is recommended as a lifelong therapy that should never be interrupted for patients with cardiovascular dis- ease. Clopidogrel therapy is mandatory for six weeks after placement of bare-metal stents, three to six months after myocardial infarction, and at least 12 months after placement of drug-eluting stents. Because of the hypercoagulable state induced by surgery, early withdrawal of antiplatelet therapy for secondary prevention of cardiovascular disease increases the risk of postoperative myocardial infarction and death five- to 10-fold in stented patients who are on continuous dual antiplatelet therapy. The shorter the time between revascularization and surgery, the higher the risk of adverse cardiac events. Elective surgery should be postponed beyond these periods, whereas vital, semiurgent, or urgent operations should be performed under continued dual antiplatelet therapy. The risk of surgical hemorrhage is increased approximately 20 percent by aspirin or clopidogrel alone, and 50 percent by dual antiplatelet therapy. The present clinical data suggest that the risk of a cardiovascular event when stopping antiplatelet agents preoperatively is higher than the risk of surgical bleeding when continuing these drugs, except during surgery in a closed space (e.g., intracranial, posterior eye chamber) or surgeries associated with massive bleeding and difficult hemostasis.

Intracardiac echocardiography is a new technique based on the use of ultrasonic diagnostic catheter, which can be introduced through the femoral vein up of the right atrium. Intracardiac echocardiography provides bidimensional views, coupled to colour and pulsed Doppler. This review summarizes multiple applications of intracardiac echocardiography in the field of interventional cardiology, particularly during percutaneous closure of patent foramen ovale or atrial septal defect. A major advantage of intracardiac echocardiography is the possibility of avoiding general anaesthesia as well as providing equivalent information to the reference technique of transoesophageal echocardiography.

Antiplatelet drugs and intraoperative haemorrhage Current literature demonstrates that there is less risk involved in maintaining anti-aggregant therapy (which might imply to transfuse more the patients), than in stopping it, which then increases dangerously the risk of coronary thrombosis. Aspirin, as a secondary preventive drug, should not be interrupted. Clopidogrel is essential for protection against thrombosis in areas where the endothelium is not intact. Unless there is a high hemorrhagic risk in closed cavities (intracranial surgery), clopidogrel should not be interrupted. Furthermore, any surgical intervention increasing the coagulability of the platelets, it seems particularly dangerous to stop such medication perioperatively.

This paper answers to the main questions the surgeon is asking before an intervention on a cardiac valve. The optimal timing of surgery, the type of intervention (repair versus replacement), the complementary investigations and the treatment of associated arythmias are discussed. Particular emphasis is put on the best technique to solve these problems.

Aims: Mitral valve prolapse is a common source of severe mitral regurgitation in Western countries. Three-dimensional echocardiography can provide views of the entire valve, allowing a complete assessment of the valve leaflets and commissures. It has the potential to precisely locate and quantify mitral valve prolapse. Methods and results: Between January 1997 and December 2000, 91 patients with severe mitral regurgitation due to mitral valve prolapse underwent a transesophageal echocardiography with three-dimensional reconstruction of the mitral valve as part of their pre-operative work-up. The location and extent of the prolapse by echo was compared to the surgical status. The volume of prolapsing leaflet was calculated and compared to the volume of resected tissue whenever a repair was attempted. There was an excellent correspondence between the echographic localization of the prolapse and surgical inspection, and between the volume of prolapsing and surgically resected tissue ( r = 0.94, p

Objectives: To evidence the respective advantages and drawbacks of minimal invasive-thoracotomy (MIDCAB) and off-pump sternotomy (OPCAB) coronary bypass techniques. Methods: The perioperative and mid-term (3 months) results of the first 31 MIDCABs and 39 OPCABs performed by a single experienced coronary surgeon (F.S.) were compared. Differences were assessed by two-tailed chi-square or unpaired t-test, and significance assumed for P-values #0.05. Results: Groups were widely comparable. There were no in-hospital deaths nor permanent neurologic events. OPCAB patients received more anastomoses (mean 1.09/patient vs. 1.89/patient, P , 0:001) during a shorter coronary occlusion period (26.1 ^ 8 vs. 16.6 ^ 4.5 min, P , 0:001), whilst immediate extubation prevailed in MIDCABs (22/31 vs. 17/39, P , 0:05). Significant complications occurred in seven MIDCABs vs. none in OPCABs ðP , 0:01Þ. Other in-hospital parameters were similar. Controls at 3 months evidenced more residual discomfort among MIDCAB patients (14/30 vs. 7/39, P , 0:05). Conclusions: Differences in early complication rates may be due to a learning effect. However, OPCAB allows us to implant more grafts and is more comfortable for both patient and surgeon. These advantages may well counterbalance the cosmetic benefits of MIDCAB procedures. q 2001 Elsevier Science B.V. All rights reserved.

Summary Background Adverse environmental events occurring early in life have received little attention as predictors of disease in the later stages of life. At birth, the transition from gas exchange by the placenta to gas exchange by the lungs requires dramatic changes in the pulmonary circulation, which during this period is particularly vulnerable to noxious stimuli. We measured pulmonary-artery pressure responses to high-altitude exposure, a stimulus that causes pronounced pulmonary vasoconstriction, in young adults who had had transient perinatal hypoxic pulmonary hypertension and in controls of similar age and sex distribution. Methods Review of neonatal-care records at the Lausanne University Hospital for Children identified 15 individuals who met the eligibility criteria (birth at 3·34 weeks of gestation, persistence of hypoxaemia during ventilation with oxygen during the first week of life, and persistence of fetal circulation). Ten of these individuals agreed to take part; the control group was ten volunteers without any history of perinatal complications. Systolic pulmonary-artery pressure (by echocardiography) and arterial oxygen saturation were measured at baseline and at high altitude (4559 m). Findings The mean increase in pulmonary-artery pressure at high altitude was significantly greater (p=0·01) in the participants who had had perinatal pulmonary hypertension (from 26·2 mm Hg [SD 2·1] to 62·3 mm Hg [7·3]) than in the controls (from 25·8 mm Hg [2·3] to 49·7 mm Hg [11·3]). The fall in arterial oxygen saturation was similar in the two groups. Interpretation These findings suggest that a transient perinatal insult to the pulmonary circulation leaves a persistent and potentially fatal imprint, which when activated in adult life predisposes to a pathological response. Survivors of perinatal pulmonary hypertension may be at risk of developing this disorder in later life.

Background —Pulmonary hypertension is a hallmark of high-altitude pulmonary edema and may contribute to its pathogenesis. Cardiovascular adjustments to hypoxia are mediated, at least in part, by the sympathetic nervous system, and sympathetic activation promotes pulmonary vasoconstriction and alveolar fluid flooding in experimental animals. Methods and Results —We measured sympathetic nerve activity (using intraneural microelectrodes) in 8 mountaineers susceptible to high-altitude pulmonary edema and 7 mountaineers resistant to this condition during short-term hypoxic breathing at low altitude and at rest at a high-altitude laboratory (4559 m). We also measured systolic pulmonary artery pressure to examine the relationship between sympathetic activation and pulmonary vasoconstriction. In subjects prone to pulmonary edema, short-term hypoxic breathing at low altitude evoked comparable hypoxemia but a 2- to 3-times-larger increase in the rate of the sympathetic nerve discharge than in subjects resistant to edema ( P 2 times larger than in those resistant to edema (36±7 versus 15±4 bursts per minute, P r =0.83, P Conclusions —With the use of direct measurements of postganglionic sympathetic nerve discharge, these data provide the first evidence for an exaggerated sympathetic activation in subjects prone to high-altitude pulmonary edema both during short-term hypoxic breathing at low altitude and during actual high-altitude exposure. Sympathetic overactivation may contribute to high-altitude pulmonary edema.

Background Transcatheter closure of atrial septal defects (ASDs) has been feasible and successful. Two-dimensional echocardiography (2DE) was applied to patients before selection and during device deployment. Three-dimensional echocardiography (3DE) can provide unique anatomic perspectives that might aid in improving device closure of ASDs. Methods and Results Twenty-two consecutive patients were enrolled in an initial protocol for ASD device closure by the new DAS–Angel Wings occluder device. On the basis of transesophageal (TEE) 2DE and 3DE, 13 patients were considered eligible for device closure (9 secundum ASDs and 4 with patent foramen ovale associated with a cerebral vascular accident). Maximal ASD diameter and surrounding rim tissues were compared by TEE 2DE and 3DE and with balloon sizing measurements at catheterization. ASD size measured by TEE 2DE and 3DE correlated well ( y =1.0 x +0.049, r =.95), with good limits of agreement. However, balloon-stretched diameter measurements were systematically larger than echocardiographic measurements. Rim tissue measurements correlated well; however, TEE 3DE could demonstrate the entire shape and perimeter of the defect. Two-dimensional imaging provided reliable information during device deployment and for closure of small ASDs. However, 3DE was superior for imaging the device, especially when abnormally placed. Conclusions Three-dimensional imaging provides unique images and projections that were essential for understanding the spatial relationship of the device to the atrial septum. Three-dimensional echocardiography significantly enhanced our understanding of two-dimensional images and provided an imaging conceptualization that should aid in future development of device closures.

Transesophageal echocardiography has become a highly valuable method to assess aortic disorders. With this method, however, aortic disease has been visualized only in two-dimensional views. Advances in computer technology have introduced three-dimensional (3D) echocardiography as a developing modality in cardiac imaging. Previous efforts to obtain 3D reconstructions of the aorta, by various techniques, had limited clinical applicability. In this study we attempted to explore the feasibility and potential of 3D reconstructions of the aorta employing a widely used multiplane transesophageal imaging technique in an experimental setting and in patients. In the in vitro study, we created 35 lesions in 28 pig aortic trees (15 aortic dissections, five saccular aneurysms, five coarctations, five atheromas, and five clots within dissections). Suspending these specimens in a water bath, sequential two-dimensional images were acquired over a 180-degree rotation with a commercially available multiplane transesophageal probe and ultrasound system with a 3D software package. Data processing (digital reformation, interpolation, and segmentation) and 3D display were accomplished on an off-line computer system. 3D reconstructions were achieved and displayed in wire-frame, surface-rendered, and volume-rendered images. These 3D reconstructions corresponded well with the actual anatomic specimens in delineating the various pathologic findings. In patient studies, we collected a total of 36 studies in both adults and children with a mean age of 44.5 years (range 1 month to 82 years). In addition to normal aortas ( n = 13), the spectrum of abnormalities studied included six atheromatous lesions, four aortic dissections, 10 coarctations, one aneurysm with a thrombus, and one dilated aortic root. We were able to accomplish volume-rendered 3D images depicting the aortic lesions in their true form that could be viewed in many different perspectives in all patients. We conclude that 3D echocardiography is able to display the aorta and aortic disease in a realistic manner. Although this modality still has limitations, further improvements in computer and ultrasound technology would strengthen 3D echocardiography as a clinically viable diagnostic tool, in the evaluation of aortic disorders. (J Am Soc Echocardiogr 1997;10:120-32.)

Three-dimensional echocardiography is an emerging clinical method to assess cardiovascular disorders. The feasibility of using a linear mode scanning (parallel slicing) for transthoracic data acquisition has been demonstrated. In this study, we evaluated the feasibility of real-time transthoracic three-dimensional imaging of the heart using a fan-like scanning mode of echocardiographic data acquisition. We used a computer-driven motor to sequentially angulate transthoracic transducers over a fan-like arc up to 90 degrees. With careful ECG and respiratory gating, we acquired basic two-dimensional data set via parasternal and subcostal windows and performed dynamic three-dimensional reconstructions. The problems encountered included the need to repeat data acquisition sequences because of transducer movement or inappropriate gain and gray scale settings. From 15 scanning sequences in four patients, we were able to use ten sets of data. These yielded good quality three-dimensional studies projecting normal valves, a stenotic mitral valve, and an atrial septal defect, in a number of novel views. The valves could be visualized from above and from below as well as in other orientations, and the detailed anatomy appraised. Spatial relationships of the atrial septal defect with inferior and superior vena cava, coronary sinus, or tricuspid annulus could be uniquely displayed through views from the right side of the heart. This technique provided adequate new imaging planes not available from two-dimensional echocardiography. This experience demonstrates for the first time that transthoracic three-dimensional echocardiography using a fan-like scanning mode of data acquisition is feasible, and that it provides adequate visualization of intracardiac structures in unique projections.(ABSTRACT TRUNCATED AT 250 WORDS)