Radiotherapy-induced mitral incompetence.

Radiotherapy-induced cardiac disease is a progressive condition with symptoms beginning several years after treatment. The following article reports the case of a 48-year-old woman who had undergone mediastinal radiation therapy for Hodgkin's lymphoma at age of 15 and, more than thirty years later, suffered from congestive heart failure due to fibrotic thickening of the mitral valve. She successfully underwent mitral valve repair with patch augmentation of the anterior leaflet. Long-term cardiac follow-up of patients treated by mediastinal radiation therapy is warranted.

Ex vivo evaluation of a new neonatal/infant oxygenator: comparison of the Terumo CAPIOX Baby RX with Dideco Lilliput 1 and Polystan Safe Micro in the piglet model.

OBJECTIVE: A newly developed neonatal and infant oxygenator with a nonheparin biocompatible polymer coating, low priming volume (43 mL), high oxygen transfer, wide operating range (<1.5 L/min) and low pressure drop represents a promising solution for cardiac surgery in neonates and infants. We compared the new CAPIOX Baby RX, Terumo (BRX) with two commonly used neonatal oxygenators: Dideco Lilliput 1 (DL1) and Polystan Safe Micro (PSM) in a piglet model. METHODS: Fifteen piglets (5.6 +/- 1.3kg) were placed on standardized cardiopulmonary bypass (CPB) for 6 hours using one of the three oxygenators (n = 5 in each group). After 120 min, the system was cooled to 25 degrees C for 60 min and then returned to normothermia. Arterial and venous blood gas data and temperature were recorded continuously by a CDI500 System (Terumo). Pressure drop, FiO2 and gas flow were recorded. Blood samples were taken before CBP, after 10 min, before and after cooling, and at the end. Total blood counts, thrombin-antithrombin complex and plasma-free haemoglobin (PfHb) were measured. RESULTS: All oxygenators showed acceptable performance for the duration of CPB. The BRX had lower mean gas flow (0.33 +/- 0.05 L/min) and FiO2 (0.43 +/- 0.02%) throughout CPB than the DL1 (1.14 +/- 0.25 L/min, p = 0.006 and 0.60 +/- 0.02%, p = 0.009, respectively) or the PSM (1.47 +/- 0.87 L/min and 0.54 +/- 0.08%, p = ns). Pressure drop in the BRX group ranged from 12 to 22 mmHg. This was significantly lower than in the DL1 group (39-65 mmHg, p = 0.005). In the PSM group, values ranged between 24 and 33 mmHg (p = ns). The increase in PfHb at six hours was significantly lower in the BRX (11.3 +/- 4.2 ng/dL) versus the DL1 (42.2 +/- 6.1 ng/dL, p = 0.004) and the PSM (56.7 +/- 15.5 ng/dL, p = 0.045). CONCLUSIONS: The BRX is as safe as the DL1 and the PSM, with superior performance in pressure drop, efficient blood gas management and lower haemolysis. The BRX exhibited the lowest prime, hold-up volume and breakthrough time.

Evaluation of a novel synthetic sealant for inhibition of cardiac adhesions and clinical experience in cardiac surgery procedures.

BACKGROUND: Pericardial adhesions subject patients requiring reoperation to potential injuries to the heart, great vessels, and cardiac grafts during the re-sternotomy. These adhesions can severely complicate re-operations by making re-entry hazardous, impeding orientation and visibility, increasing the amount of blood loss, and prolonging the operation time. The efficacy of an in situ-forming polyethylene glycol (PEG) material, CoSeal surgical sealant (CoSeal), for inhibiting cardiac adhesions in an animal model is reported. It is currently estimated that 10-20% of patients undergoing aortic valve replacement and coronary artery bypass grafting (CABG) will require a second operation later in their lives. Successful clinical experience using CoSeal for sealing suture lines of the aorta and CABGs with the data reported here suggest that CoSeal may have multiple applications in cardiac surgery. METHODS: In rabbits, a sternotomy and pericardiotomy were performed to expose the heart and the epicardium of the left ventricular surface. The epicardium was abraded for five minutes with dry gauze and cotton to develop punctate bleeding. In treated animals, CoSeal(R) or Tissucol(R) was applied directly to the abraded bleeding epicardium while retracting the pericardium. The pericardium was released, and the material over-sprayed to the cut edges of the pericardium. No material was applied in control animals. RESULTS: At necropsy, CoSeal(R) was found to significantly reduce the formation of adhesions, the tenacity of the adhesions, and the percent of the abraded site with adhesions as compared to surgical control and Tissucol. Tissucol showed no significant difference from the surgical control in any adhesion parameter. CoSeal treated hearts showed re-establishment of the mesothelial layer and tissue morphology similar to a normal un-operated heart. During the clinical cardiac procedures, CoSeal was easily mixed and applied to the suture lines of the aorta and coronary artery grafts. No bleeding was found at the suture lines. CONCLUSIONS: In the rabbit cardiac adhesion model, CoSeal significantly reduced the formation of adhesions as compared to surgical control and Tissucol, and demonstrated good biocompatibility. In CoSeal treated patients undergoing cardiopulmonary bypass or vessel repair, sealing was achieved comparable to previous cases using Tissucol fibrin sealant. CoSeal effectively sealed the suture lines of the aorta and coronary artery bypass grafts.

Na(+)/H(+)-exchange inhibition and aprotinin administration: promising tools for myocardial protection during minimally invasive CABG.

OBJECTIVE: Minimally invasive coronary artery bypass grafting (CABG), carried out on the warm beating heart, does not allow conventional myocardial protection. The objective was to investigate the possibility of enhancing tolerance to ischemia during short episodes of coronary artery occlusion, based on a pharmacological approach using a selective Na(+)/H(+)-exchange inhibitor (cariporide) or a serine protease inhibitor (aprotinin). METHODS: Four groups (n=6 in each group) of sheep were subjected to 20 min of normothermic regional ischemia (first lateral branch of the circumflex artery occlusion) followed by 1 h of reperfusion. Regional wall thickening was measured using sonomicrometry, and expressed as the percentage of thickening fraction compared with baseline. Group I was the control with no treatment, group II received cariporide (1 mg/kg administered over 2 min prior to ischemia), group III was treated with aprotinin (2.10(6) kallikrein inactivation units (KIU) load followed by 500.000 KIU/h). Group IV was treated with a combination of cariporide and aprotinin at the same concentrations as in groups II and III, respectively. RESULTS: Wall thickening measurements showed that, compared with control, cariporide was largely able to suppress secondary loss of wall thickening after initial recovery during early reperfusion. Wall thickening in the ischemic/reperfused myocardial area improved from 10+/-31 to 51+/-17% at 1 h of reperfusion (P=0.002). Aprotinin improved wall thickening at the end of 1 h of reperfusion to 70+/-13% (P=0.0001). However, in this group, there was a transient loss of regional contractility similar in amplitude and time course to the one observed in the control group. A combination of cariporide and aprotinin suppressed transient contractile loss and resulted in improved wall thickening at the end of 1 h of reperfusion (65+/-22%, P=0.0002 vs. control). This value was not significantly different from the cariporide (P=0.263) or aprotinin (P=0.704) group. CONCLUSION: These data indicate that both Na(+)/H(+)-exchange inhibition and aprotinin administration are promising tools for cardioprotection during minimally invasive CABG. A combination of both treatments is able to adequately suppress loss of contractility during early reperfusion as a consequence of reperfusion injury, and results in significantly improved wall thickening at the end of 1 h of reperfusion.

Release of cardiac troponin I in antegrade crystalloid versus cold blood cardioplegia.

OBJECTIVE: The purpose of this study was to assess the efficacy of myocardial protection, comparing antegrade crystalloid cardioplegia with cold blood cardioplegia, in patients with preserved left ventricular function who were undergoing elective first coronary artery bypass grafting. Release of cardiac troponin I was used as a marker for the effectiveness of myocardial protection. METHODS: A consecutive series of 62 patients were randomly assigned to receive crystalloid or blood cardioplegia. Cardiac troponin I concentrations were determined in venous blood samples before the operation, immediately after unclamping, at 6, 9, 12, and 24 hours, and daily thereafter for 5 days. RESULTS: Rising levels of troponin I were found in all patients. The time course and peak release were similar in the crystalloid cardioplegia and the blood cardioplegia groups. No patients in either group had electrocardiographic evidence of perioperative myocardial infarction. Cardiac troponin I was able to detect small areas of myocardial damage, not revealed by electrocardiography or creatine kinase MB release. Aprotinin administration was associated with lower cardiac troponin I release in both groups. Cardiac troponin I was lower in patients whose conditions did not require electrical defibrillation after aortic unclamping, irrespective of cardioplegia type. The presence of a main stem lesion was associated with higher cardiac troponin I release only in the crystalloid cardioplegia group. CONCLUSIONS: Antegrade cold blood cardioplegia is equally effective as antegrade crystalloid cardioplegia in a randomized group of patients with preserved left ventricular function who were undergoing elective first coronary artery bypass grafting. Aprotinin administration resulted in lower cardiac troponin I release, whereas electrical defibrillation was related to a higher release irrespective of cardioplegia type. The presence of a main stem lesion resulted in higher cardiac troponin I release in the crystalloid cardioplegia group.

Combined revascularization of coronary and femoral arteries, using the ascending aorta as inflow source.

A patient with severe coronary artery disease and leg ischaemia was successfully treated with a combined revascularization procedure. The coronary arteries were bypassed with three vein grafts, and the bilateral femoral arteries were bypassed with a Dacron graft using the ascending aorta as the source of inflow. The patient recovered well and experienced no angina or claudication two years later.

Obturator bypass: a sixteen year experience with 55 cases.

Fifty-five obturator bypasses were performed over a 16 year period for limb salvage. The indications for the choice of this technique included arterial infection, aneurysm formation or soft tissue skin loss at the groin (26 patients), and extensive atherosclerotic disease of the iliofemoral vessels, precluding their use for inflow or outflow (27 patients). There were five perioperative deaths and the five-year patency rate was 37%. Long-term results after above-knee reconstruction substantially exceeded those for below-knee anastomoses (three year patency rates of 71% and 45% respectively). Due to its morbidity and mortality the decision to perform an obturator bypass should be based upon sound indications such as deep infection at the groin, or extensive multilevel arterial disease. Its usefulness in extensive multilevel arterial disease is not demonstrated.

[Formation of a phytobezoar following surgery of the stomach. Review of the literature]. / Fytobezoar vorming na heelkunde op de maag. Overzicht van de literatuur.

Phytobezoar after partial gastrectomy. An observation on phytobezoar formation after partial gastrectomy, attended by an intestinal obstruction is presented. According to a review of the literature bezoar formation following gastric surgery seems to develop in the stomach after vagotomy, and rather in the small intestine after partial gastrectomy. The etiopathogenesis of this phenomenon is analysed, and the physiopathology, the clinical manifestation, the diagnosis and therapeutic possibilities of this affection are discussed.

[Effect of the hypothalamus on membrane permeability to ionic calcium currents]. / Influence de l'hypothalamus sur la perméabilité membranaire aux courants ioniques calciques.

The hypothalamus contains two distinct zones which affect the activity of myocardial and vascular muscle. The median ventricular nucleus stimulates the liberation of peripheral catecholamines and, by so stimulating the adrenoreceptors, opens up the slow calcium canals. The resulting stimulation of the myocardial and vascular muscle cells causes tachycardia, and an increase in myocardial contraction and in peripheral resistance. The paraventricular nucleus antagonises these effects by inhibiting peripheral catecholamine secretion so blocking or slowing the passage of Ca++ through the slow calcium canals. The study of effective, active concentration of D 600, a powerful calcium antagonist, shows that the paraventricular nucleus is not a direct calcium antagonist like D 600 whose effects are not potentiated, and confirms that it acts indirectly by inhibiting peripheral noradrenaline secretion.

[Effect of stimulation of the hypothalamic paraventricular nucleus on the electrical and contractile characteristics of the myocardium in dogs]. / Influence de l'excitation du noyau paraventriculaire hypothalamique sur les caractéristiques électriques et contractiles du myocarde chez le chien.

Electrical stimulation of the hypothalamic paraventricular nucleus results in bradycardia and hypotension. A direct transtemporal approach was used to implant an insulated electrode in the site of the third ventricle. The bradycardia and hypotension have been studied previously and have been shown to be due to inhibition of the alpha and beta vascular and myocardiac adrenergic receptors. The effects of this inhibition on the electrical appearances and the mechanical and phonocardiographic parameters of myocardial contractility were observed in this present study. The force and velocity of LV isometric contraction were reduced as shown by reduction in dP/dT, the delay in its peak and the reduction of the angle between the upstroke of ventricular contraction with the base line. The onset of left ventricular ejection was delayed. The high frequency (60 and 140 Hz) components of the first heart sound disappeared, confirming their contribution to the intensity of this sound. The ECG rapid QRS phase and AV conduction time were unchanged, but the slow phase of the T wave became more negative as the depressant effect on the myocardium increased.

[Electrocardiographic changes during stimulation of the hypothalamus in the dog]. / Modifications électrocardiographiques au cours de l'excitation hypothalamique: étude expérimentale sur le chien.

Electrical stimulation in the area around the ventro-median nuclei of the hypothalamus of the dog produced changes suggestive of ischaemia in the standard bipolar and epicardial leads, principally over the apical, lateral and diaphragmatic walls of the left ventricle. It is suggested that these changes may be the central expression of orthosympathetic stimulation by released catecholamines on the permeability and membrane potentials of the myocardial cells with respect to ions, especially Ca++.

[Verbal conditioning - analysis of a paradigm]. / Verbales Konditionieren - Analyse eines Paradigmas

In this paper relevant empirical studies of verbal conditioning have been analysed - one of the first examples of the behavior theory of Skinner applied to behavior therapy. Next the verbal conditioning paradigm has been critically evaluated as to: - the formation of a theory, - its consequences to the use of psychological procedures, also in regard to the significance of verbal conditioning in therapy. In conclusion we outlined the advantage of a research strategy that with the aid of categorical observation techniques determines and predicts the transition frequency of verbalizations of the patients as a function of the therapists verbalizations.