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We report a neutron-scattering investigation on the structure and dynamics of a single-component nanocomposite based on SiO_{2} particles that were grafted with polyisoprene chains at the entanglement limit. By skillful labeling, we access both the monomer density in the corona as well as the conformation of the grafted chains. While the corona profile follows a r^{-1} power law, the conformation of a grafted chain is identical to that of a chain in a reference melt, implying a high mutual penetration of the coronas from different particles. The brush crowding leads to topological confinement of the chain dynamics: (i) At local scales, the segmental dynamics is unchanged compared to the reference melt, while (ii) at the scale of the chain, the dynamics appears to be slowed down; (iii) by performing a mode analysis in terms of end-fixed Rouse chains, the slower dynamics is tracked to topological confinement within the cone spanned by the adjacent grafts; (iv) by adding 50% matrix chains, the topological confinement sensed by the grafted chain is lifted partially and the apparent chain motion is accelerated. We observe a crossover from pure Rouse motion at short times to topological confined motion beyond the time when the segmental mean squared displacement has reached the distance to the next graft.

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Fractures of the humeral shaft are less frequent than those of the proximal humerus. The formerly recommended treatment of humeral shaft fractures was conservative according to Böhler. This still remains an adequate concept of treatment but according to a change in the technical possibilities and the demands of patients and physicians on fast restoration of function and low pain, there is a trend towards surgical stabilization of humeral shaft fractures. The implant of choice is discussed controversially and consists of various types of nails versus plating. The technique of nailing is antegrade or retrograde and depends on the localization of the fracture. In our opinion good indications for plating are combined fractures of the proximal humerus and the shaft as well as very distal humeral shaft fractures. A primary lesion of the radial nerve is no imperative indication for exploration and different studies have shown the same results for exploration after 2 or 3 months if there is no spontaneous remission.

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Clavicle fractures, especially of the mid third, are an injury commonly seen in clinical practice, therefore, there is constant earnest discussion of the optimal approach to therapy. Until recently clavicle fractures were solely the domain of non surgical management. Even displaced fractures have been successfully managed without surgery. However, complications have been reported after non surgical treatment, the most frequent being post-traumatic shortening of the clavicle with varying functional consequences for the shoulder joint and range of arm motion as well as pseudarthrosis, especially after more severely displaced fractures. Recent studies have now shown that outcomes after non surgical management of displaced fractures or shortening of the clavicle are worse than had been previously assumed. Surgical techniques for the stable fixation of clavicle fractures have been improved and a wider selection of implants for osteosynthesis of these fractures has become available. Although there is widespread consensus that undisplaced or minimally displaced clavicle fractures respond well to non surgical management, optimal treatment of displaced fractures or severe shortening is under scrutiny with regard to both the basic choice between non surgical or surgical management and implant selection. According to current research findings, surgical management of displaced clavicle fractures has advantages and appears to be superior to non surgical management. Intramedullary nailing has proven suitable for simple straight fractures, and plate fixation for multifragmentary fractures.

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Today sonography is the first line imaging method for diagnosing acute appendicitis. Experienced investigators will have an accuracy of more than 90%. Sonography can diagnose many conservatively managed diseases. The most important differential diagnoses are infectious ileocoecitis, right sided diverticulitis, appendagitis, adnexitis, ruptured or torque ovarian cysts, ectopic pregnancies. Ureterolithiasis, cholecystitis, haematomas in the psoas muscle or in the rectus muscle are rarer causes of right lower quadrant pain. Sonography can reduce the high rate of false positive clinical examinations concerning acute appendicitis. It has to be stated that an exclusion of appendicitis can only be made sonographically if the normal appendix can be seen in its full length and/or an other differential diagnosis can be depicted that explains the clinical symptoms. Mucoceles are rare cystoid lesions of the appendix. They exhibit a typical onion skin sign structure caused by different mucus viscosities. In large mucoceles a tumor causes this lesion.

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Sonography is the primary diagnostic method in the painful left lower quadrant. Experienced investigators can diagnose an acute diverticulitis in more than 90%. In unclear cases or when complications are suspected, CT should be performed. Sonography can diagnose most differential diagnosis of the painful left lower quadrant as colitis, appenagitis or haematomas.

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AIM: To evaluate axillary sentinel lymph-node (SLN) identification and localisation with gamma probe-assisted sonography. PATIENTS AND METHODS: The study comprises 42 patients. Sonographically guided peri-lesional injection of the radiopharmacon was performed on 40 breasts. Two patients with melanoma of the upper extremity underwent intracutaneous injection. After the acquisition of images with the gamma camera, the delineated lymph nodes were marked on the skin. A high-frequency transducer with an adapted gamma probe was then used to identify the SLN. Before surgery, the SLN was localised with a hook-wire. Node activity was controlled intraoperatively. RESULTS: In two out of 42 cases, lymphatic mapping did not reveal SLNs. Multiple SLNs at different sites, all with similar activity, were demonstrated in one patient, while in another patient the sonographically visible lymph nodes were too small for exact correlation. Hook-wire localisation of the SLN was performed in the remaining 38 axillary spaces. Gamma probe-assisted sonography allowed for correct localisation of SLNs in 35/38 patients (92 %). Localisation was not correct in 3 patients (8 %), but in all cases the hook-wire was located next to the SLN. CONCLUSION: Preoperative identification and correct localisation of the SLN is possible in a high percentage of cases. This method allows rapid intraoperative detection of the SLN and could be used for exact correlation of sonographic appearance and histopathological results.

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Due to their superficial position, the parotid, the submandibular, and the sublingual glands can be imaged with high-resolution transducers. In acute inflammatory diseases sonography can differentiate between obstructive or non-obstructive sialoadenitis. Abscess formations may be detected and the maturation of the colliquation may be controlled. Abscesses may be punctured under US guidance. In Sjögren's syndrome the sonographic changes correlate with the histological destruction, and in acute forms hypervascularization is found in color Doppler. In fibrotic cases the stimulation-induced hyperemia is impaired. In sialoadenosis inflammatory and tumorous lesions can be ruled out by sonography. Tumors of the salivary glands can be visualized with high sensitivity. Like other imaging methods the specificity in assessment of the histology of a tumor is low. Multilocular lesions, such as sarcoidosis, lymphoma, metastases, or cystadenolymphoma, are discussed. In deep located, malignant tumors or when the tumor cannot be delineated completely, MR or CT are obligatory to delineate the tumor. Sonography enables the diagnosis of cysts or ranulae. The accuracy of sonography in assessment of sialolithiasis is approximately 90%. Non-opaque stones can be visualized, too; however, small stones of less than 2 mm are difficult to detect since the posterior shadow may be missing. The concrements can be differentiated into intraductal or intraglandular stones. Indirect signs, such as ductal dilatations or inflammatory changes, may be found. Pseudotumorous lesions, such as hypertrophy of the masseter muscle, tuberculosis, sarcoidosis, or lymphoepithelial lesions in AIDS, are discussed. In children the main differential diagnosis of salivary gland pathologies are addressed. In many diseases sonography is the first-line imaging modality in assessment of salivary glands.

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AIM: To investigate the sonographic signs of epiploic appendagitis in a larger number of patients and to add new details. PATIENTS AND METHODS: Over a period of approximately 8 years 28 patients were sonographically diagnosed to have epiploic appendagitis. The following sonographic signs were investigated: echogenicity of the lesion; compressibility; shape of the lesion; adherence to the anterior abdominal wall; peripheral rim; central hypoechoic line; thickening of the colonic wall. In 11 of these patients colour Doppler sonography was performed. In addition all 28 patients underwent CT. RESULTS: In 28/28 cases (100 %) a moderately hyperechoic, ovoid, non-compressible mass adjacent to the colon was demonstrated. The mass was surrounded by a hypoechoic rim in 20 cases (71 %) and was fixed to the abdominal wall in 26/28 cases (93 %). Five cases (18 %) revealed a central hypoechoic line, and slight thickening of the colonic wall was visible in 2 cases (7 %). In those cases where colour Doppler sonography was performed, colour flow was absent in the central part of the lesion. In the peripheral zone slightly increased colour flow was demonstrable in 9/11 cases. CONCLUSION: Epiploic appendagitis has a characteristic sonographic appearance with a moderately hyperechoic, ovoid, non-compressible lesion adjacent to the colon and adherent to the abdominal wall. The mass is frequently surrounded by a hypoechoic rim. Colour Doppler sonography shows a central avascular area and slightly increased colour flow in the peripheral zone.

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AIM: To investigate the ability of sonography to diagnose diverticulosis and to demonstrate the typical appearance of normal diverticula. PATIENTS AND METHODS: Sixty consecutive patients underwent sonography for prospective evaluation of the presence of diverticulosis of the left hemicolon. Diverticula were assessed for number, diameter, echogenicity, and wall thickness. Sonographic results were compared with those of endoscopy. RESULTS: Sonography yielded positive results in 28/33 patients (85 %) with endoscopically proven diverticulosis. Sonography on average could demonstrate less diverticula per patient than endoscopy. Two sonographic results were false positive. Diverticula had a maximum average diameter of 8.7 mm and the diverticular wall measured 1 mm at most. In many cases the diverticular wall could not be demonstrated by sonography. All diverticula except for one were hyperechoic. In 39 % of patients with diverticulosis one or more diverticula showed clear acoustic shadowing indicative of a faecalith. The maximum diameter of the colonic wall was 3.3 mm on average. Sonography could demonstrate the descending colon in all cases. The sigmoid colon was not visible in 3 cases and could rarely be evaluated in its entire length. CONCLUSION: Sonography can diagnose diverticulosis of the left hemicolon in most cases. Normal diverticula present as hyperechoic protuberances of the colonic wall with acoustic shadowing of varying intensity. The diverticular wall is thin and often not demonstrable at sonography.

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Knowledge about the effects of cardiopulmonary bypass on malarial patients is scant. Malaria-induced hemolysis can exercerbate by performing extracorporeal circulation on a patient infected with Plasmodium and may, therefore, lead to a critical hemolysis jeopardizing the clinical outcome. A 52-year-old patient suffering from malaria and endocarditis was scheduled for urgent aortic valve replacement. During extracorporeal circulation, free hemoglobin showed an increase to maximum of 392.5 mg/L (normal range < 50 mg/L), while haptoglobin decreased to the lowest value of 0.56 g/L (normal range 0.3-2.0 gL). Although hemolysis increased, pump run, weaning, and the postoperative course were uneventful.

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Isolated anterior mitral leaflet prolapse, unlike posterior prolapse, is a difficult lesion to repair and may become a demanding surgical procedure. We report our experience with a technique of a triangular resection of the anterior leaflet to repair isolated segmental anterior leaflet prolapse in 18 patients. This technique simplifies the repair procedure and is a safe and rapid procedure which allows excellent results.

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OBJECTIVES: Modified ultrafiltration (MUF) significantly reduce blood loss and transfusion requirements in pediatric cardiac surgery presumably by a reduction in inflammatory mediators which decrease the inflammatory axes and decrease the cross-activation of fibrinolysis and thrombosis. The influence of MUF on blood loss and homologous blood transfusion in adult cardiac surgery has not yet been determined. Furthermore, data about the influence on routine coagulation tests, platelet activation as well as the coagulation and fibrinolytic systems are limited. METHODS: In a prospective randomized study 48 patients scheduled for elective myocardial revascularization were randomized into a control group (n=16), a conventional ultrafiltration (CUF) group (n=16) and a MUF group (n=16). Perioperatively, serial blood samples were drawn at specific intervals to evaluate coagulation, fibrinolysis, and platelet function. RESULTS: Neither the coagulation nor the fibrinolytic system was positively influenced by MUF or CUF. The routine clotting tests were comparable except for a significantly higher antithrombin III activity after MUF compared to the CUF control group persisting 24 h postoperatively. Platelet factor 4 activity and platelet counts showed no differences among the groups. MUF considerably reduced the postoperative blood loss (MUF, 6.4+/-1.7 ml/kg bw per 24 h vs. CUF, 9.2+/-2.5 ml/kg bw per 24 h (P=0.003) vs. control, 8.9+/-2.2 ml/kg bw per 24 h (P=0.008)) and allogeneic blood transfusion (MUF, 2.0+/-3.4 ml/kg bw per 24 h vs. CUF, 6.9+/-5.1 ml/kg bw per 24 h (P=0.034) vs. control, 7.0+/-6.3 ml/kg bw per 24 h (P=0.029)). CONCLUSIONS: MUF in adult cardiac surgery significantly reduces postoperative blood loss and transfusion requirements. The mechanism for reduced blood loss could not be elucidated in this study.

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BACKGROUND: Ischemic mitral regurgitation (MR), when ischemia/infarction has resulted in fibrotic degeneration and elongation of papillary muscles, carries a high risk for the patient and a technical challenge for the surgeon. We have developed a papillary-shortening plasty for this specific pathology. METHODS: Papillary muscle repair was performed in 88 patients (7.2%) where degenerated and fibrotic elongated papillary muscles were found, which resulted in a prolapse of one or more parts of the mitral valve leaflets (MR III-IV). All patients had a papillary muscle-shortening plasty using a pericardium pledged-reinforced polytetrafluoroethylene suture and a ring annuloplasty. Because the cause of regurgitation in this specific group of patients was ischemic, concomitant coronary bypass grafting was required in all patients, with 2.2 grafts/patient. RESULTS: There were five hospital deaths (5.7%). Postoperative mitral valve function was satisfactory in all patients: no residual mitral regurgitation (MR 0) was found in 80 patients (90.9%), mild regurgitation (MR I) in 5 patients (5.7%), and moderate regurgitation (MR I-II) was observed in 3 patients (3.4%). Within a short mean follow-up period of 18.6 months (3 to 40 months), there was one late death (1.2%). The actuarial freedom from reoperation and thromboembolic complications was 100%, but there were two anticoagulation-induced gastric bleeding complications (2.3%). All patients were in New York Heart Association functional class I or II at the time of follow-up. CONCLUSIONS: Our data show that careful assessment of papillary muscle pathology is mandatory, and that a papillary muscle-shortening plasty is a simple but valuable surgical tool to repair the mitral valve in this specific group of high-risk patients with ischemic mitral regurgitation.

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BACKGROUND: Performing subclavian artery cannulation in patients with an atherosclerotic ascending aorta or acute aortic dissection is of growing interest. To increase knowledge about pressure and flow distribution in the arch vessels, we investigated the in vitro perfusion characteristics in right subclavian artery cannulation. METHODS: Pressures and flow rates in the arch vessels of an aortic arch model were measured during perfusion through the right subclavian artery with different geometries and varying flow rates. Flow visualization was performed by laser light. RESULTS: In normal subclavian artery geometries, pressure and flow showed a significant increase in only the right common carotid artery (8 mm Hg and 25.5 mL/min, respectively, at 5.5 L/min pump flow). In cases of 50% stenosis at the right subclavian artery origin, a reduction of pressure and flow (6 mm Hg and 22.5 mL/min, respectively, at 5.5 L/min pump flow) in the right carotid artery caused by a suction effect was observed. CONCLUSIONS: Right subclavian artery cannulation provides a valuable alternative for ascending aortic cannulation, enabling nearly balanced arch vessel perfusion. Stenosis at the right subclavian artery origin carries the potential risk of slightly reduced perfusion of the right common carotid artery with questionable clinical relevance.

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OBJECTIVE: During extracorporeal circulation design and orientation of aortic cannulae tips mainly determine flow pattern in the aortic arch and arch vessels which is the objective of this in vitro study, comparing single versus multiple stream cannulae. METHODS: In an aortic arch glass model, jet streams of 21-24 French aortic cannulae which were inserted in the ascending aorta were directed alternatively at the different arch vessels. Flows and pressures in the arch vessels were measured at pump flows of 3-6 l/min. RESULTS: With optimal orientation of the jet stream in the aortic arch, no preferential flow in the arch vessels was seen. In the single jet stream aortic cannulae group a significant parallel increase in flow and pressure in the jet streamed arch vessels compared to the non-jet streamed arch vessels occurred (P < 0.05). With the jet stream directed on vessel 2 (left carotid vessel) there was a significant pressure and flow difference comparing the two non-jet streamed vessels with each other (P < 0.03). In the single stream 24 French cannulae the highest vessel pressure of 168 mmHg and an increase in flow of 186 ml/min was measured in the jet streamed left carotid artery at 6 l/min pump flow. The multiple stream cannulae provoked the highest vessel pressure of 106 mmHg in the corresponding jet streamed vessel and an increase in flow of 20 ml/min. CONCLUSION: Tip design of aortic cannulae and the orientation of its jet stream are potential sources of remarkable imbalance of arch vessel perfusion especially with single jet stream cannulae. These effects are more pronounced with single jet stream cannulae. These results may have important clinical implications regarding perfusion of arch vessels during extracorporeal circulation.

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OBJECTIVES: Several studies documented higher complication rates after cardiac surgery in patients with splanchnic hypoperfusion. Although it is prone to errors, gastric tonometry probably is the method of choice for detecting splanchnic hypoperfusion. While there are many reasons for splanchnic hypoperfusion, low cardiac output because of hypovolemia is one of the important ones in cardiac surgery. Thereby endogenous vasoactive substances, such as angiotensin II and the kinins, might be of special interest. METHODS: Following approval from the local ethics committee, 40 patients undergoing elective cardiac surgery were studied. Every patient received a TRIP NGS Catheter (Tonometrics Division Instrumentarium Corp., Helsinki, Finland). Using radioimmunoassays and chromatography angiotensin II and bradykinin was measured before, during and immediately after cardiopulmonary bypass. Using saline tonometry gastric mucosal CO2 was measured ten times perioperatively. Patients were shifted into two groups by dichotomization at the median of gastric mucosal pH (pHi) and the pCO2 gap (gastric mucosal pCO2-arterial pCO2) before surgery. Volume substitution, use of vasoactive drugs, haemodynamic instability and time of extubation were documented. RESULTS: During cardiopulmonary bypass group I (pHi < 7.32 and CO2 gap > 3.85 mmHg) showed higher expression of angiotensin II and lower expression of bradykinin then group II (pHi > 7.32 and CO2 gap < 3.85 mmHg). The most significant difference was found on bypass. Immediately post bypass there was still a difference in the bradykinin expression. Before bypass no differences was found. In group I significantly more volume had to be substituted for haemodynamic stabilisation. These patients needed more often vasoactive drugs and in tendency were extubated later. At the time of extubation no group-difference was found as in the pHi as in the CO2 gap as in the amount of substituted volume. Patients with previous high pHi and low CO2 gap had lowest respectively highest values at the time, when fluid-balance was most negative. CONCLUSIONS: Splanchnic hypoperfusion in cardiac surgery probably correlates with hypovolemia and therefore leads to vasoconstriction, wich is shown in higher expression of angiotensin II and lower of bradykinin. Gastric mucosal tonometry in cardiac surgery probably detects hypovolemia and therefore predicts haemodynamic instability. Therefore gastric mucosal tonometry could probably be used as a therapeutical sign for a sufficient cardiac output and therefore for tissue oxygenation in general.

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BACKGROUND: Precise labeling of sizer and valve diameters is crucial for optimal valve selection especially in the small aortic root. This study examines the accuracy of manufacturers' markings on small aortic prostheses and sizers. METHODS: Sizer and valve dimensions of 22 different mechanical aortic prostheses (19 to 23 mm) were evaluated by caliper micrometer measurements. RESULTS: Nearly all sizers exceeded their marked dimensions by up to 1.0 mm. Measured tissue annulus diameters for 19-mm-labeled valves varied between 18.3 and 19.6 mm, for 21-mm valves from 20.5 to 21.6 mm, and for 23-mm valves from 22.4 to 23.5 mm, respectively. The orifice areas ranged from 1.5 to 2.06 cm2 for 19-mm valves, from 2.0 to 2.55 cm2 for 21-mm valves, and from 2.4 to 3.09 cm2 for 23-mm valves, respectively. CONCLUSIONS: Actual sizer dimensions and tissue annulus diameters of various small mechanical aortic prostheses varied considerably from their marked diameters. These differences should be considered to ensure the optimal prosthesis selection for each patient.

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The clinical relevance of transcranial Doppler sonography for the evaluation of cerebral perfusion and cerebrovascular regulatory mechanisms, as well as for the registration of embolic events, has increased considerably as a technique of non-invasive monitoring. The continuous measurement of blood flow velocities in two different vessel segments, either ipsilateral or contralateral, is limited by intricate probe fixation and positioning for optimal insonation of the vessel on the one hand. On the other hand probes are displaced frequently during anaesthesiological measures, so that continuous registration during induction of anaesthesia is not always guaranteed. In view of these limitations, a new probe-positioning and holding device has been developed and tested in a clinical study of patients undergoing cardiac surgery (n = 22). The newly designed probe-positioning and holding device allowed the unilateral adjustment and continuous measurement of the blood flow velocity in the middle cerebral artery (Vmca) from anaesthesia induction to endotracheal intubation in all patients (n = 9). This was possible in only 61.5% (n = 8) of the patients who were monitored via conventional mode of probe fixation (n = 13). The new method rendered possible the positioning, insonation and measurement in two vessel segments in 77.8% of the patients, in contrast to 53.8% of the patients where the conventional technique was used. The newly designed probe holding device meets all standard requirements from the anaesthesiological viewpoint, and facilitates the perioperative application of transcranial Doppler sonography for non-invasive monitoring.

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The authors describe their experience, in a prospective survey, with the prevalence rates of intestinal parasites in patients with hepatic cirrhosis admitted to the Gastroenterology Unit of University Hospital of Federal University in Juiz de Fora, Brazil, whose fresh stools were examined by Hoffman-Pons-Janner, Baermann-Moraes and Willis methods. They compare the results of stool exams with two control groups and look for a relation with cirrhosis' etiology. A higher prevalence of some parasites was observed in cirrhosis than in people with other digestive diseases (group I). mainly for the Strongyloides stercoralis, found in 40.2%, chiefly in alcoholic cirrhosis. Oddly no one of the group I admitted in the same period had strongyloidiasis. Another group including all the people who had stool samples examined in the same period at the hospital had 1.91% of that helmintic infection (group II). A comparison is also made with the prevalence in schoolchildren between the ages of 7 and 14 studies eight years before (13.16%). Other parasites were also observed in different incidence between those with cirrhosis and the other groups and the results are presented. They conclude that hepatic cirrhosis must be included in the list of conditions which increases the risk of Strongyloides stercoralis infection.

PIP: In a prospective study conducted between July 1995 and June 1996 the prevalence of intestinal parasites is described in 35 (32 male, 3 female) patients with hepatic cirrhosis, aged 13-77 years, who had been admitted to the gastroenterology unit of the Federal University in Juiz de Fora, Brazil. The causes of cirrhosis were: alcohol (19 cases), hepatitis B virus (HBV) (3 cases), hepatitis C virus (HCV) (5 cases), HBV and HCV (2 cases), cryptogenetics (3 cases), Wilson's disease (1 case), biliary cirrhosis (1 case), and Gaucher's disease (1 case). Another 45 patients who were hospitalized during this period served as controls (Group I). Group II was comprised of 1411 persons who underwent parasitological tests during December 1995 and May 1996. Comparison was also made with 7371 tests performed in children aged 7-14 years who had been studied in 1988. Stools were examined by the Hoffman-Pons-Janner, Baermann-Moraes, and Willis methods. The results of stool exams were compared with those of the two control groups. A higher prevalence of some parasites was observed in cirrhosis patients than in patients with other digestive diseases (Group I). Of the 35 cirrhosis patients, 19 presented with positive parasite tests. Strongyloides stercoralis was found in 40.2%, chiefly in alcoholic cirrhosis patients, which was significant when compared to the other two control groups, but not significant when compared to the patients with nonalcoholic cirrhosis (4 cases of strongyloidiasis out of 16 patients). None of the 45 patients in Group I had strongyloidiasis. Group II (including all the people who had stool samples examined during the same period in the hospital) had a 1.91% rate of helminthic infection. A rate of 13.16% was found in the children's group.

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OBJECTIVE: To assess the impact of a dynamic cardiomyoplasty on failing hearts, it is essential to estimate the contraction force of the skeletal muscle and how its contraction is synchronized with the heart cycle. METHODS: In a 6-month study a small fluid-filled, balloon-mounted catheter was placed between the myocardium and the muscular wrap in five adult female Boor goats and two female domestic pigs. The catheter was connected to a subcutaneous measuring chamber whereby pressure monitoring could be accomplished. Distinct pressure signals as a result of function of the dynamic cardiomyoplasty and the heart were detected initially in all animals. RESULTS: Maximal relative pressure from the dynamic cardiomyoplasty was calculated as 336.2% +/- 69.4% on day 24 +/- 6.1 (n = 7) and end-stage pressure as 59.8% +/- 9.7% on day 174.6 +/- 13.1 (n = 4). A functional loss of pressure signals from the dynamic cardiomyoplasty was correlated to severe histologic muscle damage (n = 3). Pressure signals transferred from the contracting myocardium to the catheter showed defined segments of contraction, ejection, and filling periods, allowing a mechanical synchronization of the dynamic cardiomyoplasty to the heart cycle. CONCLUSIONS: This monitoring catheter enabled the assessment of the functional state of the dynamic cardiomyoplasty and allowed a synchronization to the heart cycle. It will promote understanding and might help to avoid muscle damage in dynamic cardiomyoplasty for an improved outcome of the surgical treatment of end-stage heart failure.

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