Value of thoracic computed tomography in the first assessment of severely injured patients with blunt chest trauma: results of a prospective study

OBJECTIVE: The aim of this prospective study was to evaluate whether early thoracic computed tomography (TCT) is superior to routine chest x-ray (CXR) in the diagnostic work-up of blunt thoracic trauma and whether the additional information influences subsequent therapeutic decisions on the early management of severely injured patients. PATIENTS AND METHODS: In a prospective study of 103 consecutive patients with clinical or radiologic signs of chest trauma (94 multiple injured patients with chest trauma, nine patients with isolated chest trauma), an average Injury Severity Score of 30 and an average Abbreviated Injury Scale thorax score of 3, initial CXR and TCT were compared after initial assessment in our emergency department of a Level I trauma center. RESULTS: In 67 patients (65%) TCT detected major chest trauma complications that have been missed on CXR (lung contusion (n = 33), pneumothorax (n = 27), residual pneumothorax after chest tube placement (n = 7), hemothorax (n = 21), displaced chest tube (n = 5), diaphragmatic rupture (n = 2), myocardial rupture (n = 1)). In 11 patients only minor additional pathologic findings (dystelectasis, small pleural effusion) were visualized on TCT, and in 14 patients CXR and TCT showed the same pathologic results. Eleven patients underwent both CXR and TCT without pathologic fundings. The TCT scan was significantly more effective than routine CXR in detecting lung contusions (p < 0.001), pneumothorax (p < 0.005), and hemothorax (p < 0.05). In 42 patients (41%) the additional TCT findings resulted in a change of therapy: chest tube placement, chest tube correction of pneumothoraces or large hemothoraces (n = 31), change in mode of ventilation and respiratory care (n = 14), influence on the management of fracture stabilization (n = 12), laparotomy in cases of diaphragmatic lacerations (n = 2), bronchoscopy for atelectasis (n = 2), exclusion of aortic rupture (n = 2), endotracheal intubation (n = 1), and pericardiocentesis (n = 1). To evaluate the efficacy of all those therapeutic changes after TCT the rates of respiratory failure, adult respiratory distress syndrome, and mortality in the subgroup of patients with Abbreviated Injury Scale thorax score of > 2 were compared with a historical control group, consisting of 84 patients with multiple trauma and with blunt chest trauma Abbreviated Injury Scale thorax score of > 2, prospectively studied between 1986 and 1992. Age (38 vs. 39 years), average Injury Severity Score (33 vs. 38), and the rate of respiratory failure (36 vs. 56%) were not statistically different between the two groups, but the rates of adult respiratory distress syndrome (8 vs. 20%; p < 0.05) and mortality (10 vs. 21%; p < 0.05) were significantly reduced in the TCT group. CONCLUSIONS: TCT is highly sensitive in detecting thoracic injuries after blunt chest trauma and is superior to routine CXR in visualzing lung contusions, pneumothorax, and hemothorax. Early TCT influences therapeutic management in a significant number of patients. We therefore recommend TCT in the initial diagnostic work-up of patients with multiple injuries and with suspected chest trauma because early and exact diagnosis of all thoracic injuries along with sufficient therapeutic consequences may reduce complications and improve outcome of severely injured patients with blunt chest trauma.     

Congestive heart failure in patients with valvular aortic stenosis. A clinical and echocardiographic Doppler study

The aim of this study was to evaluate echographically anatomic and functional features of the left ventricle in adult patients with valvular aortic stenosis according to the presence or absence of congestive heart failure and the level of ventricular performance. Fifty-six adult patients with moderate-to-severe aortic stenosis underwent echocardiographic Doppler examination in order to evaluate left ventricular mass and dimensions, systolic function and filling dynamics. Twenty-seven patients had no heart failure and were symptomatic for angina (5), syncope (4) or were symptom-free (group I); the other 29 had heart failure (group II): 16 with normal left ventricular systolic performance (fractional shortening > 25%, group IIa) and 13 with systolic dysfunction (fractional shortening < or = 25%, group IIb). Despite a similar left ventricular mass, compared to group IIa, group IIb showed a significant left ventricular dilatation (end-diastolic diameter: 61 +/- 6.5 vs. 45.5 +/- 6.1 mm, p < 0.001) and mild or no increase in wall thickness (11.5 +/- 1.6 vs. 14.9 +/- 2 mm, p < 0.001). Indices of left ventricular filling on Doppler transmitral flow were also significantly different between the two groups, with a higher early-to-late filling ratio and a shorter deceleration time of early filling in group IIb (2.8 +/- 1.9 vs. 1.2 +/- 0.85, p < 0.01, and 122 +/- 66 vs. 190 +/- 87 ms, p < 0.05, respectively), both indirectly indicating higher left atrial pressure. Finally, heart failure was generally more severe in group IIb patients. In some patients with aortic stenosis, symptoms of heart failure may be present despite a normal left ventricular systolic function and seem to depend on abnormalities of diastolic function. The presence of systolic or isolated diastolic dysfunction appears to be related to a different geometric adaptation of the left ventricle to chronic pressure overload.     

Differentiating thrombus from pannus formation in obstructed mechanical prosthetic valves: an evaluation of clinical, transthoracic and transesophageal echocardiographic parameters

OBJECTIVES: We sought to determine the clinical and echocardiographic parameters that differentiate thrombus from pannus formation as the etiology of obstructed mechanical prosthetic valves. BACKGROUND: Distinction of thrombus from pannus on obstructed prosthetic valves is essential because thrombolytic therapy has emerged as an alternative to reoperation. METHODS: We analyzed clinical, transthoracic and transesophageal echocardiography (TEE) data in 23 patients presenting with 24 obstructed prosthetic valves and compared the findings to pathology at surgery. RESULTS: Fourteen valves had thrombus and 10 had pannus formation. Patients with thrombus had a shorter duration from time of valve insertion to malfunction, shorter duration of symptoms, but similar New York Heart Association functional class at the time of operation. Patients with thrombus had a lower rate of adequate anticoagulation (21% vs. 89%; p=0.0028). Pannus formation was more common in the aortic position (70% vs. 21%; p=0.035). Abnormal prosthetic valve motion was detected by TEE in all cases with thrombus formation but in 60% with pannus (p=0.0198). Thrombi were larger than pannuses (total length 2.8+/-2.47 cm vs. 1.17+/-0.43 cm; p=0.038). This was mostly due to extension of thrombi into the left atrium in prosthetic mitral valves. Thrombi appeared as a soft mass on the valve in 92% of cases, whereas 29% of pannuses had a soft echo density (p= 0.007). Ultrasound video intensity ratio, derived as the videointensity of the mass to that of the prosthetic valve, was lower in the thrombus group (0.46+/-0.14 vs. 0.71+/-0.17, p=0.006). A videointensity ratio of <0.70 had a positive predictive value of 87% and a negative predictive value of 89% for thrombus. Duration from onset of symptoms to reoperation of <1 month separated thrombus from pannus formation. The best objective clinical parameter for prediction of thrombus was inadequate anticoagulation, whereas the best TEE parameters were qualitative and quantitative ultrasound intensity of the mass. The presence of either inadequate anticoagulation or a soft mass by TEE improved the predictive power of either parameter alone and was similar to that of ultrasound videointensity ratio. CONCLUSIONS: Duration of symptoms, anticoagulation status and qualitative and quantitative ultrasound intensity of the mass obstructing a mechanical prosthetic valve can help differentiate pannus formation from thrombus and may therefore be of value in refining the selection of patients for thrombolytic therapy of prosthetic valve obstruction.     

Effect of modified ultrafiltration in high-risk patients undergoing operations for congenital heart disease

BACKGROUND: Modified ultrafiltration (MUF) after cardiopulmonary bypass (CPB) in children decreases body water, removes inflammatory mediators, improves hemodynamics, and decreases transfusion requirements. The optimal target population for MUF needs to be defined. This prospective, randomized study attempted to identify the best candidates for MUF during operations for congenital heart disease. METHODS: Informed consent was obtained from 100 consecutive patients with complex congenital heart disease undergoing operations with CPB. They were randomized into a control group (n = 50) of conventional ultrafiltration during bypass and an experimental group using dilutional ultrafiltration during bypass and venovenous modified ultrafiltration after bypass (MUF group, n = 50). Postoperative arterial oxygenation, duration of ventilatory support, transfusion requirements, hematocrit, chest tube output, and time to chest tube removal were compared between the groups stratified by age and weight, CPB technique, existence of preoperative pulmonary hypertension, and diagnosis. RESULTS: There were no MUF-related complications. In patients with preoperative pulmonary hypertension, MUF significantly improved postoperative oxygenation (445 +/- 129 mm Hg versus control: 307 +/- 113 mm Hg, p = 0.002), shortened ventilatory support (42.9 +/- 29.5 hours versus control: 162.4 +/- 131.2 hours, p = 0.0005), decreased blood transfusion (red blood cells: 16.2 +/- 18.2 mL/kg versus control: 41.4 +/- 27.8 mL/kg, p = 0.01; coagulation factors: 5.3. +/- 6.9 mL/kg versus control: 32.3 +/- 15.5 mL/kg, p = 0.01), and led to earlier chest tube removal. In neonates (< or =30 days), MUF significantly reduced transfusion of coagulation factors (5.4 +/- 5.0 mL/kg versus control: 39.9 +/- 25.8 mL/kg, p = 0.007), and duration of ventilatory support (59.3 +/- 36.2 hours versus 242.1 +/- 143.1 hours, p = 0.0009). In patients with prolonged CPB (>120 minutes), MUF significantly reduced the duration of ventilatory support (44.7 +/- 37.0 hours versus 128.7 +/- 133.4 hours, p = 0.002). No significant differences were observed between MUF and control patients for any parameter in the presence of ventricular septal defect without pulmonary hypertension, tetralogy of Fallot, or aortic stenosis. CONCLUSIONS: Modified ultrafiltration after CPB is safe and decreases the need for homologous blood transfusion, the duration of ventilatory support, and chest tube placement in selected patients with complex congenital heart disease. The optimal use of MUF includes patients with preoperative pulmonary hypertension, neonates, and patients who require prolonged CPB.     

Electrophysiologic characteristics and anatomical complexities of accessory atrioventricular pathways with successful ablation of anterograde and retrograde conduction at different sites

INTRODUCTION: Catheter ablation may eliminate anterograde and retrograde accessory pathway conduction at closely adjacent but anatomically discrete sites. However, the mechanisms of this discrepancy, the electrophysiologic and anatomical characteristics, and information about systematic study from a large patient population are not available. The purpose of this study was to investigate the electrophysiologic characteristics and anatomical complexities of the accessory pathway in which anterograde and retrograde conduction was successfully ablated at different sites. METHODS AND RESULTS: Thirty-eight (10.9%) patients (19 men and 19 women; mean age 37 +/- 2.4 years) fulfilling the criteria of having separate ablation sites for anterograde and retrograde conduction were designated as group I, and the other 310 patients (215 men and 95 women; mean age 47 +/- 0.6 years) were designated as group II. The patients with right-sided free-wall pathways had the highest incidence (18.6%) of separate ablation sites. The anatomical distance between anterograde and retrograde directions (left anterior oblique view, 13 +/- 0.6 vs 8 +/- 0.9 mm, P < 0.01; right anterior oblique view, 17 +/- 0.6 vs 5 +/- 0.7 mm, P < 0.01), and incidence of conduction impairment in one direction after successful ablation of another direction (15% vs 78%, P < 0.05) differed significantly between left and right free-wall pathways. The mean distances obtained from left (7 +/- 0.4 vs 14 +/- 0.4 mm, P < 0.05) and right (7 +/- 1.1 vs 15 +/- 0.9 mm, P < 0.05) anterior oblique views were shorter in patients who had impairment of conduction properties than those in patients without impaired conduction after successful ablation of one direction. CONCLUSIONS: This study showed that anatomical and functional dissociation of the accessory pathway into anterograde and retrograde components was possible. Further study on the relation between electrophysiologic and pathologic characteristics would be helpful to confirm these findings.     

Mechanisms of luminal enlargement and quantification of vessel wall trauma following balloon coronary angioplasty and directional atherectomy

OBJECTIVES: The purpose of this study was to assess the dual action of lumen enlargement and vessel wall damage following either balloon angioplasty or directional atherectomy, using intracoronary ultrasound, and angioscopy. BACKGROUND: Differences in the mechanisms of action of balloon angioplasty and directional atherectomy may have a significant bearing on the immediate outcome and the restenosis rate at 6 months. METHODS: A total of 36 patients were studied before and after either balloon angioplasty (n = 18) or directional atherectomy (n = 18). Ultrasound measurements included changes in lumen area, external elastic membrane area and plaque burden. In addition, the presence and extent of dissections were assessed to derive a damage score. Angioscopic assessment of the dilated or atherectomized stenotic lesions was translated into semi-quantitative dissection, thrombus and haemorrhage scores. RESULTS: Atherectomy patients had a larger angiographic vessel size compared with the angioplasty group (3.55 +/- 0.46 mm vs 3.00 +/- 0.64 mm, P < 0.05); however, minimal lumen diameter (1.18 +/- 0.96 mm vs 0.85 +/- 0.49 mm) and plaque burden (17.04 +/- 3.69 vs 15.23 +/- 4.92 mm2) measurements did not differ significantly. As a result of plaque reduction, atherectomy produced a larger increase in luminal area than the angioplasty group (5.80 +/- 1.78 mm2 vs 2.44 +/- 1.36 mm2, P < 0.0001). Lumen increase after angioplasty was the result of 'plaque compression' (50%) and wall stretching (50%). Additionally, in both groups there was indirect angioscopic evidence of thrombus 'microembolization' as an adjunctive mechanism of lumen enlargement. Angioscopy identified big flaps in six and small intimal flaps in 11 of the atherectomized patients as compared with five and 12 patients in the angioplasty group. Changes in thrombus score following both coronary interventions were identical (0.72 +/- 3.42 points atherectomy vs -0.38 +/- 3.27 points balloon angioplasty, ns). CONCLUSIONS: Lumen enlargement after directional atherectomy is mainly achieved by plaque removal (87%), whereas balloon dilation is the result of vessel wall stretching (50%) and plaque reduction (50%). Despite the fact that the luminal gain achieved by directional atherectomy is twice that achieved with balloon angioplasty, the extent of trauma induced by both techniques seems to be similar.     

Transesophageal echocardiography study with dynamic spontaneous contrast of the left atrial appendage, its relationship with the anatomy and thrombus formation

OBJECTIVE: Transesophageal two-dimensional echocardiographic study of anatomical characteristics of the left atrial appendage and its relation to spontaneous dynamic echocardiographic contrast. DESIGN: Outpatients undergoing a prospective two-dimensional transesophageal echocardiographic study. SETTING: Consecutive outpatients studied at the Echocardiographic Laboratory of Gregorio Mara?on General Hospital, Madrid. MATERIAL AND METHODS: In each patient at the level of the left atrial appendage we calculated the following transesophageal echocardiographic parameters: end-systolic and end-diastolic maximal longitudinal and transversal diameters, total systolic and diastolic areas, percentage of systolic fractional shortening, presence of left atrial appendage thrombus and spontaneous dynamic echo-contrast. MAIN RESULTS: Left atrial appendage spontaneous dynamic contrast was observed in 48% of the total population. In the group of patients with left atrial spontaneous echo-contrast we observed larger longitudinal systolic (44 +/- 14 mm vs 28 +/- 13 mm, p = 0.01) and diastolic (52 +/- 16 mm vs 38 +/- 12 mm, p = 0.005) diameters, larger transversal systolic (25 +/- 10 mm vs 19 +/- 6 mm, p = 0.03) and diastolic (28 +/- 8 mm vs 25 +/- 9 mm, p = NS) diameters and also larger systolic (601 +/- 204 mm2 vs 337 +/- 110 mm2, p < 0.0001) and diastolic (715 +/- 230 mm2 vs 507 +/- 184 mm2, p = 0.001) areas, compared to the group without this dynamic echocardiographic phenomena. Left atrial appendage percentage of fractional shortening was considerably reduced in patients with spontaneous dynamic echo-contrast (15 +/- 14% vs 39 +/- 18%, p = 0.001) and related to local thrombus formation (13% vs 1%, p < 0.001). CONCLUSIONS: Left atrial spontaneous dynamic echo-contrast is more common in patients with enlarged left atrial appendage systo-diastolic diameters and areas. In this group of patients the presence of left atrial spontaneous echo-contrast is related to a significant reduction in left atrial appendage contractile function and thrombus formation. Parameter analysis of left atrial appendage anatomy by two-dimensional transesophageal echocardiography may have clinical relevance in the assessment of patients with high risk for left atria thromboembolic phenomena.     

Transesophageal echocardiography for diagnosis of traumatic injuries to the major intrathoracic vessels in 150 patients: the effect of the learning curve

OBJECTIVES: To evaluate the role of transoesophageal echocardiography (TOE) in the management of patients with suspected traumatic lesions of the thoracic aorta (TLA) and its branches; to assess the influence of the learning curve on the diagnostic accuracy of TOE for the identification of TLA. STUDY DESIGN: Retrospective study. PATIENTS: The study included 150 patients (age: 41 +/- 17; Injury Severity Scale score: 31 +/- 17) who were admitted during a 4-year period for severe blunt chest trauma and who underwent a TOE study. METHODS: TOE were performed with either a monoplane (n = 54) or a multiplane probe (n = 96). In all cases, TLA were confirmed by angiography, computed tomography, surgery, or necropsy. Initially performed routinely, angiography was subsequently indicated when the TOE study was inconclusive or when a disruption of supraaortic arteries was suspected. Echocardiographic studies were reviewed by an experienced reader who was unaware of the medical history and initial conclusions. To evaluate the influence of the learning curve on the diagnostic accuracy of TOE, these conclusions were compared with the initial interpretations. RESULTS: A TLA was recognized in 25 patients out of 150 (17%), and evidenced using TOE in 22 of them. Three false negative and two false positive TOE results (needless thoracotomy) were recorded. After a learning period, the rate of inconclusive TOE studies decreased (18/150 vs 7/150: P < 0.05) and no false positive finding was recorded. The sensitivity and specificity of TOE for the diagnosis of TLA were 88 and 100%, and positive and negative predictive values were 100 and 97%, respectively. CONCLUSIONS: TOE is an accurate imaging technique for the diagnosis of TLA located at the aortic isthmus. However aortography becomes essential when injuries of the aorta branches are suspected. A learning period is required to improve the specificity of TOE for this indication.     

Exercise hemodynamics in small (< or = 21 mm) aortic valve prostheses assessed by Doppler echocardiography

Exercise Doppler echocardiography was used to assess hemodynamics in 25 patients with a < or = 21 mm aortic valve prosthesis (14 with a Medtronic-Hall 21 mm valve, three with a Medtronic-Hall 20 mm valve, three with a Sorin 21 mm valve, one with a Duromedics 21 mm valve, and four with a Carpentier-Edwards 21 mm valve). A symptom-limited upright bicycle exercise test was performed, and Doppler gradients were recorded during exercise. Gradients increased with exercise from 30 +/- 8/16 +/- 4 mm Hg (peak/mean) at rest to 46 +/- 12/24 +/- 7 mm Hg during exercise; both p < 0.001. Mean exercise gradient exceeded 30 mm Hg in five patients, and the highest mean gradient recorded was 37 mm Hg. Within the group of mechanical valves, gradients at exercise were similar for different types of valves. A linear relationship was found between gradients at rest and during exercise (peak r = 0.75, mean r = 0.77; both p < 0.001). Additional findings were midventricular velocities exceeding 1.5 m/sec in late systole in 10 patients (40%) and intraventricular flow (> or = 0.2 m/sec) toward the apex during isovolumic relaxation in 11 patients (44%). The patients with these velocity patterns had significantly smaller left ventricular cavities (end-diastolic diameter 39.8 +/- 4.8 vs 46.5 +/- 4.2 mm, p < 0.01; end-systolic diameter 24.2 +/- 3.0 vs 28.5 +/- 4.5 mm, p = 0.013).(ABSTRACT TRUNCATED AT 250 WORDS)     

Placental transfer and neonatal effects of propofol in caesarean section

Rheumatoid arthritis (RA) patients are at higher risks of bacterial infection than healthy subjects. Polymorphonuclear leukocytes (PMN) are the first line of nonspecific cellular defence against these infections. We tested the hypothesis that abnormal directed migration of PMN may be one reason for the increased infection rate of RA patients. PMN migration was investigated in 68 peripheral blood samples of 15 RA patients compared with 64 samples of healthy controls in a novel whole blood in vitro membrane filter assay. The migration of PMNs from RA patients and controls was stimulated using the bacterial chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP). Unstimulated PMN migration of RA patients was increased compared with healthy controls as measured by the following parameters: (a) absolute number of migrant PMNs (1954+/-87 vs. 1238 +/-58 PMN/mm2), (b) percentage of PMNs migrated into the filter (total migration index, TMI) (28.6+/-0.9 vs. 24.0+/-0.8%), (c) the distance half the migrating PMNs had covered (distribution characteristic, DC) (22.6+/-1.1 vs. 16.1+/-0.6 mm) and (d) the product of TMI and DC (neutrophil migratory activity, NMA) (669.0+/-45.0 vs. 389.0+/-18.9). fMLP stimulated PMNs of RA patients showed defective migration compared to unstimulated samples as shown by (a) a reduced number of migrant PMNs (1799+/-93 PMN/mm2), (b) lower TMI (26.1+/-0.9%), (c) unremarkable altered distribution characteristic (22.9+/-0.8 mm) and (d) significant reduced migratory activity (600.0+/-30.0). Our data suggest that the high incidence of infections in RA patients may partly be caused by defective migratory activity of PMNs to bacterial chemoattractants as demonstrated by fMLP.     

Reversibility of cardiac dysfunction after valve replacement in elderly patients with severe aortic stenosis

BACKGROUND: The role of aortic valve replacement for aortic stenosis has not been fully defined in terms of the postoperative reversibility of cardiac dysfunction and pulmonary hypertension in elderly patients. METHODS: Cardiac function, assessed by radioisotope ventriculography and catheterization data, was evaluated before and after operation, and their results were compared between preoperative and postoperative data in each group of younger patients (<69 years, group I, n = 29) and elderly patients (> or =70 years, group II, n = 21). RESULTS: One month postoperatively the peak ejection rate determined by radioisotope ventriculography improved significantly in comparison with the preoperative value in elderly patients (preoperatively, 228 +/- 38 versus postoperatively, 319 +/- 116% end-diastolic volume per second, p < 0.05), although their preoperative peak ejection rate was severely depressed. The postoperative peak filling rate of the elderly group was not completely reversible to almost normal value, whereas that of the younger group was completely reversible. Early diastolic peak filling rate (one-third peak filling rate) was not reversible in both two groups. Pulmonary hypertension in the elderly patients was reversible to postoperative almost normal pulmonary artery pressure despite the severity of aortic stenosis (systolic pulmonary artery pressure preoperatively, 37 +/- 16 mm Hg versus postoperatively, 25 +/- 5 mm Hg, p < 0.02; diastolic pulmonary artery pressure preoperatively, 15 +/- 6 mm Hg versus postoperatively, 10 +/- 4 mm Hg, p < 0.05). CONCLUSIONS: Both cardiac dysfunction, reflected by reduction of peak ejection rate, and pulmonary hypertension in elderly patients with severe aortic stenosis were reversed, reaching almost normal values 1 month after operation.     

High survival rate in 122 ARDS patients managed according to a clinical algorithm including extracorporeal membrane oxygenation

OBJECTIVE: We investigated whether a treatment according to a clinical algorithm could improve the low survival rates in acute respiratory distress syndrome (ARDS). DESIGN: Uncontrolled prospective trial. SETTING: One university hospital intensive care department. PATIENTS AND PARTICIPANTS: 122 patients with ARDS, consecutively admitted to the ICU. INTERVENTIONS: ARDS was treated according to a criteria-defined clinical algorithm. The algorithm distinguished two main treatment groups: The AT-sine-ECMO (advanced treatment without extracorporeal membrane oxygenation) groups (n = 73) received a treatment consisting of a set of advanced non-invasive treatment options, the ECMO treatment group (n = 49) received additional extracorporeal membrane oxygenation (ECMO) using heparin-coated systems. MEASUREMENTS AND RESULTS: The groups differed in both APACHE II (16 +/- 5 vs 18 +/- 5 points, p = 0.01) and Murray scores (3.2 +/- 0.3 vs 3.4 +/- 0.3 points, p = 0.0001), the duration of mechanical ventilation prior to admission (10 +/- 9 vs 13 +/- 9 days, p = 0.0151), and length of ICU stay in Berlin (31 +/- 17 vs 50 +/- 36 days, p = 0.0016). Initial PaO2/FIO2 was 86 +/- 27 mm Hg in AT-sine-ECMO patients that improved to 165 +/- 107 mm Hg on ICU day 1, while ECMO patients showed an initial PaO2/FIO2 of 67 +/- 28 mm Hg and improvement to 160 +/- 102 mm Hg was not reached until ICU day 13. QS/QT was significantly higher in the ECMO-treated group and exceeded 50% during the first 14 ICU days. The overall survival rate in our 122 ARDS patients was 75%. Survival rates were 89% in the AT-sine ECMO group and 55% in the ECMO treatment group (p = 0.0000). CONCLUSIONS: We conclude that patients with ARDS can be successfully treated with the clinical algorithm and high survival rates can be achieved.     

Effects of pravastatin on thoracic aortic atherosclerosis in patients with heterozygous familial hypercholesterolemia

Data regarding the effects of plasma lipid lowering on the evolution of thoracic aortic atherosclerosis (TAA) are scarce. In this study, we performed transesophageal echocardiography to characterize TAA in 16 newly diagnosed patients with heterozygous familial hypercholesterolemia and to follow its evolution after 2 years of statin treatment. TAA was graded as follows: grade I = normal intima; grade II = increased intimal echo density without thickening; grade IIIA = increased intimal echo density with single atheromatous plaque < or = 3 mm; grade IIIB = multiple plaques < or = 3mm; grade IV = > or = 1 plaque >3 mm; and grade V = mobile or ulcerated plaques. Baseline aortic intimal morphology was grade I in one patient, grade II in 4, grade IIIA in 6, grade IIIB in 3, and grade IV in 2 patients. Hypolipidemic treatment resulted in significant reductions in plasma total cholesterol and low-density lipoprotein (LDL) cholesterol. Follow-up aortic morphology was grade I in 5 patients, grade II in 2, grade IIIA in 3, grade IIIB in 3, and grade IV in 3 patients. TAA remained stable in 7 patients, progressed in 3, and regressed in 6 patients. TAA evolved in a uniform manner in the ascending aorta, aortic arch, and descending aorta. Patients with TAA regression were younger (39+/-14 vs 52+/-8 years, p=0.038) and had a greater decrease in plasma LDL cholesterol as a result of treatment (138+/-56 vs 73+/-55 mg/dl, p=0.036) than patients with TAA stability or progression. These observations support the hypothesis that hypolipidemic treatment may favorably affect the course of TAA in patients with heterozygous familial hypercholesterolemia.     

Transesophageal echocardiographic predictors for maintenance of sinus rhythm after electrical cardioversion of atrial fibrillation

The aim of this study was to assess the value of transesophageal echocardiography (TEE) in patients with atrial fibrillation in predicting restoration and maintenance of sinus rhythm after electrical cardioversion. TEE was performed in 62 patients with atrial fibrillation before their first elective cardioversion. Clinical variables evaluated were: age, gender, duration, and etiology of atrial fibrillation. TEE variables included: left atrial (LA) length, width, and size, LA annulus size, as well as presence of LA spontaneous contrast, thrombus and mitral regurgitation, LA appendage size and flow, and left ventricular function. Based on initial outcome of cardioversion, patients were grouped into patients who remained in atrial fibrillation and in whom sinus rhythm was restored. The latter group of patients was followed for 1 year, and grouped into patients who reverted to atrial fibrillation and in whom sinus rhythm was maintained. Successful cardioversion was achieved in 50 of 62 patients (81%). None of the clinical or TEE variables were related to initial outcome. At 1-year follow-up, 29 of 50 patients (58%) who underwent successful cardioversion continued to have sinus rhythm. The following variables were related to maintenance of sinus rhythm: duration of atrial fibrillation (6.7 +/- 7.3 vs 2.0 +/- 2.4 months; p < 0.005); LA length (6.2 +/- 0.7 vs. 5.5 +/- 1.0 cm; p < 0.008); width (5.1 +/- 0.5 vs. 4.5 +/- 0.7 cm; p < 0.002); size (26.4 +/- 5.0 vs 19.8 +/- 6.5 cm2; p < 0.0005); annulus size (4.0 +/- 0.2 vs 3.7 +/- 0.3 cm; p < 0.0005); presence of LA spontaneous contrast (13 [62%] vs 4 [14%]; p < 0.002), and LA appendage flow (19 +/- 8 vs 36 +/- 15 cm/s; p < 0.0005). In multivariate logistic regression analysis, LA annulus size, but especially LA appendage flow, were significantly associated with maintenance of sinus rhythm. Thus, in TEE-guided electrical cardioversion of atrial fibrillation, variables often used to assess thromboembolic risk may also be used to predict 1-year outcome of cardioversion.     

Dimension and related anatomical distance of Koch's triangle in patients with atrioventricular nodal reentrant tachycardia

INTRODUCTION: The dimension of Koch's triangle in patients with AV nodal reentrant tachycardia has not been well described. Understanding the dimension and anatomical distance related to Koch's triangle might be useful in avoiding accidental AV block during ablation of the slow pathway. The purposes of this study were to define the dimension of Koch's triangle and its related anatomical distance and correlate these parameters with the successful ablation sites in patients with AV nodal reentrant tachycardia. METHODS AND RESULTS: We studied 218 patients with AV nodal reentrant tachycardia. The distance between the presumed proximal His-bundle area and the base of the coronary sinus orifice (DHis-OS) measured in the right anterior oblique view was used to define the dimension of Koch's triangle. The distance of the proximal His-bundle recording site from the successful ablation site (DHis-Ab) and the distance as a fraction of the entire length of Koch's triangle (DHis-Ab/DHis-Os) were determined. The mean DHis-Os and DHis-Ab were 25.9 +/- 7.9 and 13.4 +/- 3.8 mm, respectively. DHis-Os negatively correlated with patient age (r = -0.41, P < 0.0001) and body mass index (r = -0.18, P = 0.004). Among the patients with successful ablation sites in the medial area, DHis-Os was longer (27.2 +/- 6.6 vs 24.6 +/- 8.4 mm, P < 0.005), DHis-Ab was similar (12.9 +/- 3.1 vs 13.9 +/- 4.0, P > 0.05) and DHis-Ab/DHis-Os was smaller (0.48 +/- 0.04 vs 0.74 +/- 0.11, P < 0.05). Furthermore, the patients with successful ablation sites in the medial location needed more radiofrequency pulse numbers than those in the posterior location (6 +/- 4 vs 4 +/- 3, P < 0.05). CONCLUSION: The site of successful slow pathway ablation was consistently about 13 mm from the site recording the proximal His-bundle deflection in patients with AV nodal reentrant tachycardia despite marked variability in the dimensions of Koch's triangle; therefore, patients with large triangles required ablation in the medial region rather than the posterior region. Care should be taken when delivering radiofrequency energy to the posteroseptal area in patients with shorter DHis-Os to avoid injury to AV node.     

Energy requirements and physical activity in free-living older women and men: a doubly labeled water study

Determinants of daily energy needs and physical activity are unknown in free-living elderly. This study examined determinants of daily total energy expenditure (TEE) and free-living physical activity in older women (n = 51; age = 67 +/- 6 yr) and men (n = 48; age = 70 +/- 7 yr) by using doubly labeled water and indirect calorimetry. Using multiple-regression analyses, we predicted TEE by using anthropometric, physiological, and physical activity indexes. Data were collected on resting metabolic rate (RMR), body composition, peak oxygen consumption (VO2 peak), leisure time activity, and plasma thyroid hormone. Data adjusted for body composition were not different between older women and men, respectively (in kcal/day): TEE, 2,306 +/- 647 vs. 2,456 +/- 666; RMR, 1,463 +/- 244 vs. 1,378 +/- 249; and physical activity energy expenditure, 612 +/- 570 vs. 832 +/- 581. In a subgroup of 70 women and men, RMR and VO2 peak explained approximately two-thirds of the variance in TEE (R2 = 0.62; standard error of the estimate = +/-348 kcal/day). Crossvalidation of this equation in the remaining 29 women and men was successful, with no difference between predicted and measured TEE (2,364 +/- 398 and 2,406 +/- 571 kcal/day, respectively). The strongest predictors of physical activity energy expenditure (P < 0.05) for women and men were VO2 peak (r = 0.43), fat-free mass (r = 0.39), and body mass (r = 0.34). In summary, RMR and VO2 peak are important independent predictors of energy requirements in the elderly. Furthermore, cardiovascular fitness and fat-free mass are moderate predictors of physical activity in free-living elderly.     

Penetrating aortic ulcer: clinical and angiographic characteristics

BACKGROUND: "Penetrating aortic ulcer", an atherosclerotic lesion with ulceration that penetrates the internal elastic lamina and allows haematoma formation within the aortic wall, is rarely considered in the differential diagnosis of patients with sudden onset of severe chest or back pain. It has been suggested that it is a pathologic process that involves elderly hypertensive patients with severe atherosclerosis and rarely has been observed in the ascending aorta. METHODS: To determine the characteristics of this process, 11 clinical, 2 hemodynamic, 3 angiographic and 4 surgical variables were compared between 10 consecutive patients with penetrating aortic ulcers and 20 matched patients with classic acute aortic dissection. RESULTS: Clinical and hemodynamic variables were similar in both compared groups. In the group of patients with penetrating ulcer mean age was 58 +/- 6 years, previous hypertension was observed in 6 patients and the penetrating ulcer was located in the ascending aorta in 6 cases. In comparison to patients with aortic dissection, more angiographic projections were necessary to obtain the diagnosis in the group of patients with penetrating ulcer (2.4 +/- 0.8 vs 1.7 +/- 0.6; p < 0.05). In addition, the presence of angiographic aortic valve regurgitation was only observed in the group of patients with acute dissection (60% vs 0%; p < 0.001). Severe atherosclerosis was not present angiographically in any patient with penetrating ulcer. CONCLUSIONS: Penetrating aortic ulcer can also affect middle age patients without severe atherosclerosis and is frequently observed in the ascending aorta. Its form of presentation and clinical characteristics are similar to classic aortic dissection. The lack of angiographic confirmatory evidence of dissection with suggestive clinical history, should raise the possibility of penetrating aortic ulcer.     

Quantitative assessment of the operative results after extended myectomy and surgical reconstruction of the subvalvular mitral apparatus in hypertrophic obstructive cardiomyopathy using dynamic three-dimensional transesophageal echocardiography

OBJECTIVES: The aim of this study was to examine the value of dynamic three-dimensional (3D) transesophageal echocardiography (TEE) for the postoperative evaluation after extended myectomy and surgical reconstruction of the subvalvular mitral valve apparatus in patients with hypertrophic obstructive cardiomyopathy (HOCM). BACKGROUND: Two-dimensional imaging techniques such as echocardiography, computed tomography and magnetic resonance imaging have not been able to precisely quantify the effects of surgical therapy on the morphology of the left ventricular outflow tract (LVOT). METHODS: Multiplane TEE with 3D reconstruction was performed in 11 patients before and after the operation and in 16 normal control subjects for comparison. The preoperative maximal systolic pressure gradient in the LVOT was 69 +/- 59 mm Hg. The following variables were measured within the dynamic 3D data set: depth, width, length and cross-sectional area (CSA) gain caused by the myectomy trough, minimal CSA of the LVOT at each time point and its cyclic changes and maximal mitral leaflet deviation during systole. RESULTS: Functional class improved from 3.0 +/- 0.2 before the operation to 1.5 +/- 0.6 after it. The maximal systolic pressure gradient in the outflow tract decreased to 26 +/- 21 mm Hg postoperatively (p < 0.001). Minimal CSA of the outflow tract increased from 1.1 +/- 1.2 to 3.8 +/- 1.9 cm2 postoperatively (p < 0.001), similar to the value of the control group (4.2 +/- 1.5 cm2, p = NS). The area gain due to the myectomy trough was 1.3 +/- 1.0 cm2, corresponding to 48 +/- 12% of the total operative area difference. Maximal systolic depth of the myectomy was 7 +/- 2 mm, maximal width was 20 +/- 8 mm and length was 28 +/- 7 mm. Maximal deviation of the mitral leaflets fell from 15 +/- 7 to 6 +/- 7 mm postoperatively (p < 0.01). In five patients mass measurements of the intracavitary portion of the papillary muscle (PM) revealed an increase from 7.3 +/- 1.0 to 12.1 +/- 2.5 g due to surgical mobilization of PMs (p < 0.01). CONCLUSIONS: 3D TEE quantifies the differences in outflow tract morphology before and after surgery for HOCM. This technique may have an impact on the planning of operative interventions and allow for the evaluation of its results.     

Aortic rupture after blunt chest trauma. Rapid diagnosis using transesophageal echocardiography when radiographic and computed tomographic findings are unclear

HISTORY AND CLINICAL FINDINGS: A 37-year-old woman who was not wearing a seat-belt while driving a car had a head-on collision at 70 km/h. On arrival of the emergency physician she was awake and responsive but complained of pain with bruising over the sternum and the epigastrium. Pressure on the sternum was painful. Arterial pressure was 95/60 mm Hg, heart rate 112/min. On admission the heart sounds were unremarkable and peripheral pulses normal. Vesicular sounds were heard over both lungs. In addition to multiple facial abrasions voluntary movements were impaired and the right knee-joint was swollen. INVESTIGATIONS: The ECG showed sinus tachycardia (103 beats/min) with left axis deviation, but was otherwise unremarkable. Initially the haemoglobin was 12.6 g/dl with normal white cell and platelet counts. Clotting tests, serum transaminases, creatine kinase, lactate dehydrogenase and other routine laboratory tests were within normal limits. TREATMENT AND COURSE: Because the haemoglobin level had fallen to 7.7 g/dl within the first 4 hours erythrocytes concentrate was infused. The chest radiogram and subsequent computed tomography showed a mediastinal and paraaortic haematoma of unclear origin. Transoesophageal echocardiography (TEE) demonstrated rupture of the descending aorta with free floating intraluminal parts of the intima in the isthmal region, just distal to the origin of the left subclavian artery, which was not occluded. Colour Doppler echocardiography revealed abnormal flow into mediastinal and paraaortic tissues. At operation the echocardiographic findings were confirmed and part of the descending aorta was replaced by a 3 cm dacron tube during an aortic crossclamping time of 37 min. The patient was discharged after a postoperative stay of average length, during which her other injuries were treated. CONCLUSION: After blunt thoracic or deceleration trauma earliest possible TEE is indicated, because it can at once provide details of extent and degree of injury to heart and/or aorta.     

Stent placement compared with balloon angioplasty for obstructed coronary bypass grafts. Saphenous Vein De Novo Trial Investigators

BACKGROUND: Treatment of stenosis in saphenous-vein grafts after coronary-artery bypass surgery is a difficult challenge. The purpose of this study was to compare the effects of stent placement with those of balloon angioplasty on clinical and angiographic outcomes in patients with obstructive disease of saphenous-vein grafts. METHODS: A total of 220 patients with new lesions in aortocoronary-venous bypass grafts were randomly assigned to placement of Palmaz-Schatz stents or standard balloon angioplasty. Coronary angiography was performed during the index procedure and six months later. RESULTS: As compared with the patients assigned to angioplasty, those assigned to stenting had a higher rate of procedural efficacy, defined as a reduction in stenosis to less than 50 percent of the vessel diameter without a major cardiac complication (92 percent vs. 69 percent, P<0.001), but they had more frequent hemorrhagic complications (17 percent vs. 5 percent, P<0.01). Patients in the stent group had a larger mean (+/-SD) increase in luminal diameter immediately after the procedure (1.92+/-0.30 mm, as compared with 1.21+/-0.37 mm in the angioplasty group; P<0.001) and a greater mean net gain in luminal diameter at six months (0.85+/-0.96 vs. 0.54+/-0.91 mm, P=0.002). Restenosis occurred in 37 percent of the patients in the stent group and in 46 percent of the patients in the angioplasty group (P=0.24). The outcome in terms of freedom from death, myocardial infarction, repeated bypass surgery, or revascularization of the target lesion was significantly better in the stent group (73 percent vs. 58 percent, P = 0.03). CONCLUSIONS: As compared with balloon angioplasty, stenting of selected venous bypass-graft lesions resulted in superior procedural outcomes, a larger gain in luminal diameter, and a reduction in major cardiac events. However, there was no significant benefit in the rate of angiographic restenosis, which was the primary end point of the study.