Cardiopulmonary bypass copolymer surface modification reduces neither blood loss nor transfusions in coronary artery surgery.

OBJECTIVE: Surface-modifying additives (SMA) have been suggested for improving cardiopulmonary bypass (CPB) circuit biocompatibility, potentially minimizing inflammatory complications and bleeding associated with CPB. The purpose of this prospective, randomized clinical study was to compare a novel copolymer surface-modified CPB circuit (SMARXT; COBE Cardiovascular) against the unmodified circuit. METHODS: We randomized 122 patients with isolated coronary artery disease subjected to first-time surgery on CPB into either the SMA (n = 62) or the control group (n = 60). Exclusion criteria included renal insufficiency, liver disease, coagulopathy, anticoagulation therapy < 6 days preop, carotid artery stenosis > 70 %, and a history of stroke. We collected perioperative clinical data including drainage blood loss, transfusion requirements, duration of mechanical ventilation, and ICU stay. Platelet function was determined pre- and post-CPB. RESULTS: SMA patients received 3.2 +/- 0.9 (SD) grafts during 48 +/- 16 min of aortic cross clamp and 91 +/- 30 min CPB (Control: 3.0 +/- 0.9 grafts; p = 0.33, 46 +/- 14 min AXC; p = 0.36, and 84 +/- 23 min CPB; p = 0.14). In the SMA group, 23 patients (37 %) received red blood-cell transfusions, 9 patients (15 %) fresh frozen plasma, and 3 patients (5 %) received platelets (control: n = 27 [46 %], p = 0.44; n = 10 [17 %], p = 0.91; and n=4 [7 %], p = 0.71, respectively). Platelet count on CPB fell to the same level in both groups. In SMA patients, platelet function decreased from 94.2 +/- 24.9 % pre-CPB to 79.5 +/- 32.8 % post-CPB (p = 0.043) (control: from 87.7 +/- 25.6 % to 69.4 +/- 34.7 %; p = 0.001). Postoperative drainage blood loss, mechanical ventilation duration, and ICU stay were similar in both groups (p > 0.3). One patient of the control group was excluded due to surgical bleeding, and one SMA patient died. CONCLUSIONS: Our results show that the surface-modified CPB circuit decreased neither blood loss nor transfusions despite slightly better platelet function preservation compared to the unmodified circuit. This type of CPB circuit surface modification does not appear to improve clinical outcome in low-risk coronary artery surgery patients.

The significance of oncometry for infusion therapy during pediatric heart surgery.

BACKGROUND: The colloid osmotic pressure (COP) is not routinely assessed during pediatric heart surgery. Two cases of unrecognized hyperoncotic states associated with renal failure have been observed after pediatric heart surgery. We studied the hypothesis that the COP cannot be estimated from the total plasma protein (TPP) or albumin level. METHODS: The course of COP and its correlation to the TPP and albumin level were investigated in 25 children undergoing elective heart surgery. Infusion therapy was performed solely on the basis of clinical parameters and TPP/albumin levels. COP values were determined in a blinded fashion at the end of the study. RESULTS: No correlation between TPP/albumin and the COP could be determined preoperatively. On arrival at the ICU correlation was strong. A weak correlation was observed at 24 hours and 48 hours after surgery. However, the observed wide range of the confidential bands indicates that the COP cannot be estimated correctly, neither from the TPP, nor from the albumin level. Due to colloidal oversubstitution COP was significantly increased compared to preoperative level at 48 hrs following surgery. CONCLUSIONS: As estimation of COP from TPP or albumin level is inaccurate, oncometry should be performed during pediatric heart surgery.

The importance of colloid osmotic pressure measurements to prevent oncotic overdosage during cardiac surgery.

OBJECTIVE: Colloidal infusion therapy during cardiac surgery has changed from the principal use of human albumin to the preference for synthetic colloids. Despite the possible interference of synthetic plasma expanders with the biuret determination of total plasma protein (TPP), perioperative infusion therapy is frequently directed on the basis of TPP and albumin levels. The hypothesis that the level of TPP or albumin does not reflect the plasma colloid osmotic pressure (COP) if synthetic plasma expanders are used was studied. MATERIALS AND METHODS: In 61 patients undergoing elective cardiac surgery the course of COP and its correlation to the TPP and albumin levels were investigated. Natural and artificial colloids were used for colloidal infusion therapy. RESULTS: No correlation between TPP/albumin levels and COP was found preoperatively and on arrival at the ICU, only a weak correlation was observed at 24 hours and 48 hours postoperatively. The wide range of the confidential interval indicates that the COP cannot be estimated correctly neither from the TPP nor the albumin level. The postoperative COP was significantly increased compared to the preoperative levels indicating oncotic overdosage. CONCLUSIONS: In order to avoid oncotic disturbances, indication for colloidal volume replacement during cardiac surgery should be controlled by oncometry if natural and synthetic colloids are administered.

The significance of anticardiolipin antibodies and anti-heart muscle antibodies for the diagnosis of postpericardiotomy syndrome.

Postpericardiotomy syndrome (PPS) is a frequent complication after cardiac surgery. In a recent study, elevated anticardiolipin antibody (ACLA) titres were observed in patients with PPS. The value of anti-heart muscle antibodies (AHA) for the diagnosis of PPS remains controversial. Therefore, a prospective double-blind study was performed to test the sensitivity and specificity of ACLA and AHA for the diagnosis of PPS. ACLA titres (ELISA) and AHA, elevated by immunofluorescence, the clinical course and routine laboratory parameters were assessed in 57 patients before and after elective cardiac surgery. ACLA increased and AHA first appeared after surgery in patients both with and without PPS. The sensitivities of a > or = 1.5-fold increase in IgM-ACLA titres, of a > or = 2-fold increase in IgG-ACLA titres and of the occurrence of AHA > or = 2+ for the diagnosis of PPS were 60%, 20% and 20%. The respective specificities were 43%, 79% and 85%. Thus, after cardiac surgery, increased ACLA titres and the occurrence of AHA, as assessed by immunofluorescence, may only contribute to the diagnosis of PPS to a limited extent.

Budd-Chiari syndrome as the primary manifestation of a fibrolamellar hepatocellular carcinoma.

An 18-year-old female patient was admitted with ascites, right upper abdominal tenderness and peripheral edema. Angiography showed complete occlusion of the vena cava inferior up to the level of the right atrium. By open heart surgery, masses of thrombotic material were pulled out of the v. cava inferior/vv. iliacae which histologically contained tumor cell populations consistent with a hepatocellular carcinoma. Celiacography showed a highly vascularized tumor in the right hepatic lobe. Histologically, it proved to be fibrolamellar subtype hepatocellular carcinoma.

Left hemitruncus in adulthood: diagnostic role of magnetic resonance imaging.

The diagnosis of left hemitruncus and large patent ductus arteriosus was made by magnetic resonance imaging in an adult patient with recurrent haemoptysis and dyspnoea on exertion. Previous cardiac catheterization and echocardiography failed to establish the complete diagnosis. Magnetic resonance imaging using spin-echo and gradient-echo pulse sequences is a useful imaging modality to evaluate anatomical and functional abnormalities in patients with complex congenital heart disease.

Transposition of the great arteries with straddling tricuspid valve. Report of two rare cases with acquired subaortic stenosis after main pulmonary artery banding.

The clinical, hemodynamic, angiocardiographic, and postmortem findings of a previously unreported type of subaortic stenosis are presented in two patients who also had straddling tricuspid valve and transposition of the great arteries. The subaortic stenosis became apparent after banding of the main pulmonary artery and was due to hypertrophy of a probably abnormally positioned moderator band resulting in a double-chambered right ventricle. Fibrous tissue accumulation at the stenotic os infundibuli also contributed to the subaortic obstruction. Both patients had situs solitus of the atria. Patient 1 had ventricular inversion (L-loop ventricles) and atresia of the right-sided mitral valve. Patient 2 had normally positioned ventricles (D-loop) and two atrioventricular valves. The presence of a large left ventricle and a small right ventricle in the angiocardiogram led to the erroneous diagnosis of a single left ventricle with an infundibular outlet chamber in both patients. Consequently, the subaortic obstruction was thought preoperatively to be at the site of a restrictive bulboventricular foramen. Patient 1 died 36 hours after placement of a valved conduit from the left ventricle to the descending aorta. Patient 2 was operated on successfully and the surgical procedures performed are described.

[Form of manifestations and course of brachial plexus lesions following medial sternotomy]. / Manifestationsform und Verlauf von Plexusläsionen nach medianer Sternotomie.

A prospective study is reported of the prevalence, the clinical picture and the course of plexus brachialis lesions following median sternotomy during heart operations. The study comprises 1,585 patients. In 22 patients (1.39%) a lesion of the lower plexus brachialis was found postoperatively. In 12 patients the plexus lesion was combined with an ipsilateral Horner syndrome. The present study suggests that in spite of cautious use of the sternal retractor, the appearance of a postoperative plexus lesion cannot be completely avoided. In contrast to a cranial incision of the retractor, which can be associated with a posterior fracture of the first rib, a caudal placement of the retractor seems to induce a superior luxation of the first rib and local hematoma without concurrent fracture. Re-examinations of the patients demonstrated a good prognosis of these plexus lesions, the Horner syndromes, however, may remain for a longer time period. It is advisable that patients who have to undergo a heart operation with median sternotomy should be informed beforehand about the possible side-effects described here.

Determination of central blood volume and extravascular lung water.

UNLABELLED: In patients undergoing thoracic surgery central blood volume is subject to large variations and extravascular lung water may change critically due to fluid shifts. Therefore, an accurate monitoring of these parameters, in particular under perioperative conditions, seems to be desirable. This study describes an improved method for the measurement of intrathoracic volumes. Experiments were carried our in 9 mongrel dogs under piritramide-N2O anesthesia. In order to produce low cardiac output in combination with uneven distribution of perfusion, measurements were performed under base line conditions and after postural changes. Indicators (cold and indocyanine green dye) were injected into the v. cava and indicator kinetics were recorded from the pulmonary artery and aorta using thermistor-fiberoptic catheters. The transport functions of cold and dye were computed from the corresponding pairs of dilution curves. From the transport functions, the mean transit times of the intravascular (dye) and diffusible (cold) indicator were determined. Central blood volume and extravascular lung thermal volume were calculated from the mean transit times and a thermodilution cardiac output. RESULTS: Under base line conditions, central blood volume was 15.3 +/- 2.5 ml/kg body weight. In orthostasis, a significant and reversible reduction to 11.6 +/- 2.4 ml/kg body weight was found. Cardiac output fell significantly from 3.3 +/- 0.5 to 2.4 +/- 1.1. l/min. In contrast, the slight decrease of extravascular lung thermal volume was not statistically significant. It is concluded that the method presented is sensitive enough to detect even small changes of central blood volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Biology of metastasizing ameloblastoma.

The present report of a malignant metastasizing ameloblastoma and a critical review of literature was undertaken in an attempt to better understand the biological potential and behavior of this rare tumor and thus to facilitate its clinical management. Most of the 26 patients with a proven malignant ameloblastoma including the present case had developed multiple recurrences. The lung was the most frequent metastatic site (88%) followed by regional lymph nodes (27%). Furthermore metastases were observed in some cases in the bone, brain, kidney, small intestine and liver. The interval between diagnosis of tumor and manifestation of metastases was long with a median of 11.1 years. The average survival time was 13.1 years. By contrast, the interval between diagnosis of metastatic disease and death was relatively short (median: 2.6 years). The histologic and cytologic pattern of malignant ameloblastoma and of its metastases was not significantly different from that of non-metastatic ameloblastoma. Because of the lack of morphological criteria of malignancy the biological behavior of ameloblastomas cannot be predicted. It is difficult to be certain which factors are important in the delayed induction of metastases. It is suspected that ameloblastomas possess an inherent low grade malignancy which is stimulated by multiple recurrences. It is further assumed that the metastatic tumor cells have a slow growth rate resulting in late clinical manifestation of metastases. When lung metastases occur we recommend their surgical removal in order to prolong live expectancy or even to obtain a curative effect.

Discrete subaortic stenosis: the value of cross-sectional sector echocardiography in evaluating different types of obstruction.

The value of cross-sectional sector echocardiography in the visualization of discrete subaortic stenosis (DSS) was investigated using an 80 degrees phased-array sector scanner with simultaneously derived M-mode outputs. Thirty-three patients (including 22 postoperative patients) with proven DSS were investigated and divided into two groups: group I--discrete membranous type; and group II--diffuse fibromuscular type. In group I (15 patients), two isolated subaortic ridges were identified as discrete linear echoes in the long axis of the outflow tract in five patients. A single distinct and isolated linear echo was observed in three patients, whereas in another five the ridges appeared to be attached to the ventricular septum and/or to the base of the anterior mitral leaflet. In two patients with mild DSS, a false-negative diagnosis was made. Only 2 out of 12 patients in this group showed a short remnant of the ridge after surgical revision. In group II, a more generalized or long-segment narrowing was present in 18 patients; in 14 of them the ridges were continuous with the walls of the outflow tract. Eight out of ten patients reexamined following resection of fibromuscular tissue still had residual obstruction. Analysis of the simultaneous M-mode recordings revealed that the transient appearance of the ridge in the outflow tract depended on the normal movement of the heart within the chest, on the lengthening of the membrane itself, and on the angle between the ultrasound beam and the membrane during different cardiac cycles. Our study shows that a spectrum of one- and two-dimensional patterns exists depending on the nature of the obstructing lesion. Cross-sectional sector echocardiography provides more direct visualization and characterization of various types of DSS than M-mode echocardiography does.

[Ventricular septal defect as a complication of myocardial infarct]. / Der Ventrikelseptumdefekt als Komplikation des Myokardinfarkts.

Between 1978 and 1982 emergency closure of postinfarction ventricular septal defect was performed in 4 patients (51--74 years) on the 3rd-7th day after acute myocardial infarction. All patients had a large left-to-right shunt and were in intractable acute heart failure; all of them survived the operation (3 patients had additional aortocoronary bypass grafts), and follow-up (0.5--4.5 years) was uncomplicated. The favorable clinical and functional results of surgical therapy indicate that postinfarction ventricular septal defects should be operated on even in patients over 70 years of age.

Quantitative nuclear angiocardiography in valvular heart disease.

A noninvasive method of quantitative nuclear angiocardiography was developed using a camera system and a computer. The investigation, which can be performed on an out-patient basis within 10-15 min, includes the following steps: injection of 10 mCi 99mTc-labelled human serum albumin into a femoral vein, and external recording of the passage of the bolus through the central circulation by a sequence of scintigraphic frames taken during diastole. From time--activity curves over the right ventricle, the pulmonary artery and the left ventricle, peak-to-peak times and mean circulation times were calculated. The method was applied to 424 patients with valvular heart disease proven by heart catherization. The following results were obtained: (1) The method proved to be highly sensitive in stating whether there was a hemodynamically significant valvular disease or not. But differential diagnosis concerning the different forms of valvular disease was not possible. (2) The prolongation of the circulation times correlated with the hemodynamic severity of the disease. (3) The circulation times were directly related to the cardiac index, the enddiastolic volume of the left ventricle and the pressures in the pulmonary vascular system. (4) The method could be used to evaluate the effect of surgery and for follow-up after operation. Quantitative nuclear cardiography may help to fill the gap between the nonquantitative, rather unspecific and the specific but invasive methods of cardiologic investigation.

[Supporting the pumpfunction of the right atrium. A new therapeutic concept after physiological repair of tricuspid atresia (author's transl)]. / Mechanische Unterstützung des rechten Vorhofes. Ein neues therapeutisches Prinzip nach Korrektureingriffen bei Trikuspidalatresie.

A new indication for the External Conterpulsation (ECP) is demonstrated. Due to the venous augmentation a "pulse wave" is created in the V. cava inferior and in the right atrium and the ECP acts as a "peripheral pumpventricle", thus increasing pulmonary blood flow and left ventricular enddiastolic pressure. This new application of ECP is of valve in cases with low output syndrome after physiological repair of tricuspid atresia as demonstreated in a case report.

[Haemodynamics and tolerance to hypoxia of the myocardium under 6%-oxygen ventilation following acute isovolaemic haemodilution in experimental animals (author's transl)]. / Hämodynamisches Verhalten und Hypoxietoleranz des Myokards unter 6%-Sauerstoffmangelbeatmung nach akuter isovolämischer Hämodilution in Tierexperiment

1. In experiments on closed chest dogs in a control group and a group of previous isovolaemic haemodiluted dogs a cardiovascular stress was produced by means of reduction of inspiratory O2 content to 6% O2--2. Under haemodilution only small changes of the heart rate, aortic pressure and dp/dtmax occurred, pointing to a decreased sympathoadrenergic response. Augmentation of LVEDP and pulmonary artery pressure is considered to be related to left ventricular insufficiency.--3. According to haemodynamic changes myocardial O2 demand in the control group during hypoxia is increasedby 120% and in contrast remains unchanged after previous haemodilution.--4. Despite the reduced oxygen content under haemodilution severe arterial hypoxemia affects mean survival time of the animals (18.5 min and 21.5 min respectively) only little. However, there is a greater variation from 11 to 26 min in the haemodiluted animals.

[Haemodynamics, oxygen demand and oxygen uptake of the heart during isovolaemic haemodilution (author's transl)]. / Hämodynamik, Sauerstoffbedarf und Sauerstoffversorgung des Herzens unter isovolämischer Hämodilution

1. In experiments on 5 closed chest dogs an isovolaemic haemodilution with 6% dextran resulted in a drop of haemoglobin content to 6,4g%. Except for a small decrease of arterial pO2 and O2-saturation the body oxygen supply remained undisturbed. -- 2. According to only very small haemodynamic alterations (except compensatory cardiac output increase) myocardial O2-demand increased very little and mainly is caused by moderate augmentation of ventricular wall tension. The decrease of arterial O2 content was fully compensated by an increase of myocardial blood flow. O2 supply to the myocardium was not critically changed. -- 3. In accordance with other investigators it is concluded that in case of coronary insufficiency or increased myocardial O2 demand intentional hemodilution should be avoided. Patients with myocardial insufficiency considered for therapeutic hemodilution should be digitalized preoperatively.

[Functional scintigraphy of the heart: correlations with cardiological parameters]. / Funktionsszintigraphie des Herzens: Korrelation mit kardiologischen Parametern

According to Zierler's theoretical deduction time activity curves obtained from different parts of the central circulation after injection of a bolus of radioactivity are dependent on the volume and the flow. We tried to prove this by experiments and checked simultaneously the quality of the method developed by us using a Gamma Camera and a computer. We correlated the peak to peak time from the right to the left ventricle and the mean transit time of the left ventricle with the cardiac index and the enddiastolic volume of the left ventricle in patients with valvular heart disease. For this purpose patients were selected in whom either the cardiac index or the enddiastolic volume of the left ventricle were in the normal range. Under these conditions there was a highly significant correlation between these parameters. Moreover the mean pressure of the pulmonary artery and the mean pulmonary wedge pressure correlated significantly with the peak to peak time from the right ventricle to pulmonary artery. This may be explained by the correlation between the volume of the pulmonary vascular system and its pressures. As expected, there was no correlation between the time parameters from the nuclear medicine method and the enddiastolic pressure of the left ventricle in patients with valvular heart disease. The results are in good agreement with the diagnostic accuracy of the method in recognizing valvular heart disease as well as with the correlation between the hemodynamic stage in valvular heart disease and the change of the time parameters of the time activity curves.

[Improvement of myocardial blood flow and cardiac hemodynamic by means of intraaortic balloon pumping IABP during experimental heart failure (author's transl)]. / Verbesserung der Koronardurchblutung und Kreislaufstabilisierung durch intraaortale Ballongegenpulsation IABP nach experimenteller Herzschädigung

The influence of the intraaortic balloon pumping (IABP) on the hemodynamic and coronary blood flow under control conditions and after experimental heart failure induced by coronary artery ligature was proved on eight dogs. By timely use of IABP (systolic pressure over 60-70 mmHg), the cardiac hemodynamics can be improved by means of reducing myocardial oxygen demands, and on the other hand by raising the coronary perfusion and oxygen supply.