Rupture of guide wire during percutaneous transluminal coronary angioplasty. Mechanics and management.

Two rare cases of rupture of the guide wire during percutaneous transluminal coronary angioplasty are described. Both patients required emergency surgical retrieval of the retained fragments and myocardial revascularization. The possible mechanics of the event and the options in the management are discussed with a review of the literature on this rare complication of percutaneous transluminal coronary angioplasty.

Intestinal ischemia associated with cardio-pulmonary-bypass surgery: a life threatening complication.

Intestinal ischemia following open heart surgery is rare but nevertheless extremely dangerous and the causes are still unclear. The purpose of this study was to evaluate the factors influencing the occurrence and outcome of patients with this complication. At our institution between 1985 and 1989 1712 patients underwent open heart surgery and 4 female patients suffered from intestinal ischemia. The early mortality was 2.5% for the whole group and 100% for the group with intestinal ischemia. All these 4 patients were elderly and had a history of hypertension and hyperlipoproteinemia. Three of the four patients with intestinal ischemia had various risk factors for thromboembolic events such as pre-existing occlusive arterial disease and cardiac dysrhythmias or had a complicated postoperative course. In two patients an enormous increase in serum lactate to over 10 mmol/l occurred prior to the intestinal ischemia. We therefore consider advancing age, female gender and a susceptibility for thromboembolic events as important risk factors for the development of intestinal ischemia. A serum lactate over 10 mmol/l should lead to an aggressive diagnostic and therapeutic approach including exploratory laparotomy.

[Heart replacement (biventricular assisted circulation) with the ellipsoid heart (E-BVAD) (author's transl)]. / Funktioneller Herzersatz (biventrikuläre assistierte Zirkulation) mit dem Ellipsoidherz (E-BVAD).

At the present time mechanical assisted circulation is indicated in patients with cardiac failure after open heart operations. The results after clinical implantation of the left ventricular assist devices are not encouraging. However, most of these patients suffer from irreversible cardiac failure and no restitution is to be expected. In patients with postoperative cardiac failure, a distinction must be made between isolated left heart failure and total heart failure. In patients with total heart failure - for example with diffuse, marked coronary sclerosis - both left and right ventricle failure exists. In these patients, no left ventricular assist device per se can bring the desired effect, since due to the right heart failure syndrome, the left system does not work adequately. With the biventricular bypass it is possible to maintain complete circulation in cases of cardiac insufficiency. The cannulation concept is biventricular transatrial to the aorta or to the pulmonary artery. The technique is simple and can be carried out very quickly. In cases of clinical emergency this device can be recommended due to the satisfactory haemodynamic effects achieved and the small degree of traumatic haemolysis. It represents an easy and quick implantable system for total functional heart replacement.

[Acute implantation technique of the ellipsoid heart for clinical left ventricular assistance (author's transl)]. / Akute Einsatzform des Ellipsoidherzens zur klinisch assistierten Zirkulation.

The results of the first clinical trials of left ventricular assist devices are not encouraging. The only indication at present is in patients with cardiac failure after cardiac operations. The acute type of ellipsoid heart described in this paper-displays a canulation technique where the inflow canula inserted in the left ventricular cavity via the left atrium and the outflow canula is directly connected to the aortic canula of the cardiopulmonary bypass. The haemodynamic response shows the efficacy of this system. The circulation can be maintained in severe cardiac failure, as well as in ventricular fibrillation and cardiac arrest. On the basis of data obtained in experiments on 7 female calves this system is considered worthy of clinical trial.

Coronary revascularization in DACH: 1991-2002.

BACKGROUND: The changes in coronary revascularization in Europe in general and in the DACH countries (Deutschland, Austria, Switzerland) in particular between 1991 - 2002 were studied. METHODS: The databases of different national surgical societies, registries, and governments and international organizations and collegial responses were analyzed. RESULTS: The population of Europe (excluding Russia, CIS, and Turkey) increased by 2.29 % from 1991 to 521.84 million in 2002 and by 4.7 %, 3.4 %, and 7.4 % in Austria (AT), Germany (DE), and Switzerland (CH), respectively. The DACH countries contributed 18.76 % to the European population in 2002. During this period the cardiac surgery (CS) output increased in Europe, AT, DE, CH by 108 % to 428 477 (821/million population), by 72 % to 7035 (859/million), by 244 % to 125 341 (1521/million), and 61 % to about 8600 (1175/million), respectively. Coronary artery surgery (CAS) output increased by 108 % to 241 567 (463/million), by 83 % to 4559 (557/million), by 159 % to 73 929 (897/million), and by 37 % to about 5000 (684/million), respectively. DACH contributed 34.6 % of CAS volume in Europe in 2002. CAS average volume/center/year rose from 301 in 1991 to 392 in 2002 in Europe, 312 --> 506 in AT, 538 --> 936 in DE, and changed to 331 --> 278 in CH. The percentage of CAS in CS hardly changed from 56.2 % in 1991 to 56.4 % in 2002 in Europe but changed from 61 % --> 64.8 % in AT, 67.5 % --> 58.98 % in DE, and 68.1 % --> 58.2 % in CH. Acceptance of OPCAB remains low at 5 - 18 % of CAS. The increase in percutaneous coronary interventions (PCI) volume was more impressive: the 2002 average of PCI/million was 1244 in Europe, 1659 in AT, 2524 in DE, and 1708 in CH; 36 % of the total number of European PCI was done in DACH. In 2002, coronary stenting was done in 83 % of PCI in Europe: with 1039/million in Europe, 1399/mill (84 %) in AT, 1994/mill (79 %) in DE, and 1435/mill (84 %) in CH. The average European total coronary revascularization activity (PCI + CAS) increased from 1991 by 257 % to 1707/million in 2002; in DACH it increased by 261 % to 3243/million. CONCLUSIONS: Coronary revascularization productivity in Europe during the last decade has continued to grow (mostly in the PCI sector) but has lagged behind that in the USA. The pattern of coronary artery surgery remains fairly consistent in DACH while CAS productivity is far ahead of the rest of Europe despite recent plateauing. The trend towards PCI was equally pronounced in AT, DE, and CH.

[Atypical adenoma of the thyroid gland [author's transl)]. / Atypisches Schilddrüsenadenom.

A total of 2204 nonmalignant goiters surgically removed during the years 1958, 1959, 1960 and 1966 were reexamined. Among them 181 adenomas were found, which were classified as 'atypical' by cytological respectively histological means. Those patients who had been primarily operated on at our hospital were questioned about the clinical course after the operation. Our results show a benign development of atypical thyroid adenomas, which means no recurrence of this type of adenoma nor metastasing in either of the cases during the observation period. The criteria of the WHO (Hedinger u. Sobin, 1974) for malignancy typing (with special emphasis on vascular invasion and caposular penetration and less attention to the histological structure and nuclear polymorphism) are thus verified. With exact histological exclusion of malignity, we believe, that in case of atypical adenoma, thyroidectomy is not necessary. Nevertheless a careful postoperative control of the patient is strictly indicated.

[Carcinoma of the kidney in hairy cell leukemia (author's transl)]. / Nierenkarzinom bei Haarzell-Leukämie.

In a 59-year old man hairy cell leukemia was diagnosed by blood smear, bone marrow smear, and bone marrow cytochemistry 1 year before he died from heart failure. No cytotoxic drugs had been given. Interestingly enough, besides hairy cell leukemia, autopsy revealed a carcinoma of the kidney that had not featured any clinical symptoms.

Artificial blood and extracorporeal circulation (ECC).

To investigate a possible clinical use in ECC of artificial blood (AB) by means of a stroma free, polymerized and pyridoxylated hemoglobin a feasibility study was performed. Group I (5 calves) served as control. Group II (5 calves) received 2000 ml of a mixture of one part AB and one part Ringer's solution, group III (5 calves) 2000 ml of AB as priming solution. Blood samples were taken preoperatively, at 6 h, 24 h and then weekly up to 1 month. All animals survived and could be weaned from the ventilator immediately after the operation. Total hemoglobin was 10.6 before and 9.5 g/dl 12 h after the operation in mean in the group I and 11.5 and 11.9 for group II and III. Aortic mean pressure was increased in group II/III from preoperatively 105/95 mmHg to 124/135 mmHg after the end of cardio pulmonary bypass (CPB). The pulmonary vascular resistance increased in group II/III from 92/52 to 214/264 dyn*s*cm-5 in mean. This could not be observed in group I. Pulmonary resistance correlated with the concentration of free plasma hemoglobin.

Hydraulic driving unit and control system for artificial hearts.

A driving unit for artificial ventricles was constructed in which the power transmission is hydraulic. This avoids the danger of an air embolism, which is characteristic of pneumatic drives in the case of membrane rupture. An electromagnet as a power source drives a rolling membrane pump to move the transmission fluid to the artificial ventricle. This incompressible connection allows direct control of membrane motion and pumped blood volume simply by measuring the armature stroke. The volume-controlled mode is characterized by automatic self-regulation according to Starling's law and self-synchronization when the drive is used as a left (or right) ventricular assist device. Several measures were taken to increase the operational safety. The hemodynamic efficiency of the drive was tested in a number of in vivo experiments. The long-term stability was proven in a 12-month durability test.

Orthotopic heart replacement by nonpulsatile axial blood pumps.

In the last decade, there have been many experiments with nonpulsatile blood pumps to perform functional heart replacement by biventricular assist devices. To determine if life is sustainable with nonpulsatile blood flow, two nonpulsatile blood pumps were implanted in the orthotopic position as an artificial heart after removal of the natural heart in extracorporeal circulation. In three preliminary experiments, the feasibility of total heart replacement with nonpulsatile implantable blood pumps was shown.

[Surgical therapy of coronary disease: aortocoronary bypass. Risks and complications]. / Chirurgische Therapie der koronaren Herzerkrankung: aortokoronarer Bypass. Risken und Komplikationen.

The aorto-coronary bypass surgery is a well established method for treating patients with coronary artery disease. In the last five years at the University Clinic in Innsbruck 417 operations have been performed. The operation letality decreased down to 0.66%, whereby the mean revascularisation rate increased to 2.8. The specific aim of this paper is to show the benefits and the risks of this operation to validate and to verify the benefits in regard to the risks, which could be kept very low.

Early and late results following coronary bypass surgery beyond the age of 75 years.

The indication for coronary bypass surgery in the elderly has been dramatically expanded in recent years. The results, however, are often contradictory. 1,538 consecutive patients undergoing cardiac surgery were divided into two groups by their age at the time of operation: younger than 75 years (n = 1,480) and 75 years and older (n = 58). These groups were compared with regard to influencing factors of early and late mortality, morbidity, and quality of life. Preoperatively, the clinical condition of the group greater than or equal to 75 years was significantly worse than the condition of the group less than 75 years (NYHA IV: greater than or equal to 75 years: 63.8%; less than 75 years: 31.9%). Cerebrovascular diseases occurred more often in the patients greater than or equal to 75 years (stroke or transient ischemic attack: greater than or equal to 75 years: 8.6%; less than 75 years: 2.3%). The necessity of carotid reconstruction prior to coronary surgery was significantly higher in the patients greater than or equal to 75 years: (greater than or equal to 75 years: 5.2%; less than 75 years: 1.5%). Diabetes mellitus could be observed in 19.0% of the patients greater than or equal to 75 years and in 10.1% of the patients less than 75 years. The preoperative ejection fraction was similar in both groups. Cardiopulmonary bypass time and crossclamping time of the aorta did not differ significantly. Both groups received approximately the same number of distal coronary anastomoses. Rethoracotomy due to hemorrhage had been observed more often in the older group (greater than or equal to 75 years: 8.6%; less than 75 years: 4.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

A new hydraulic heart assist device.

For the right drive of a hydraulic biventricular assist device (HBVAD), a new lightweight magnet with a permanent magnetic armature was constructed. A miniature optically incremental position sensor was developed, which is an integral part of the control loop of the driving unit, and was incorporated in the armature. Mock circulation tests proved the stability of the drive and showed the expected sensitivity to the preload pressure. In vivo experiments in calves were carried out in order to test its haemodynamic efficiency on a beating and on a fibrillating heart, and to test the mutual interaction of the left and right hydraulic assist devices (LVAD, RVAD) via the vascular system. Both drives were controlled independently, operating in the volume-controlled mode. For the modelling of a heart disease, the heart was blocked by the administration of verapamil (Isoptin). It could be shown that the HBVAD is able to maintain the circulation. Various tests with the left and/or right drive active showed distinct unloading effects for the natural heart and proved the mutual interaction of both drives via the vascular system. An inherent feature of the hydraulic drive system is its ability to be triggered by a (weakly) beating heart. The preload sensitivity of the HBVAD was tested by the administration of adrenaline. Similar reactions of the drives resulted for a beating and for a fibrillating heart, showing the regulation characteristic according to Starling's law.

[Late complications following Björk-Shiley and Carpentier-Edwards heart valve replacements]. / Spätkomplikationen nach Björk-Shiley- und Carpentier-Edwards-Herzklappenersatz.

Valve related and valve induced, fatal or non fatal complications after Björk-Shiley valve replacement (n = 50) are compared with complications following Carpentier-Edwards valve replacement (n = 113). These patients had been operated upon between 1976 and 1982 and were followed up until 1985. Estimated actuarial cumulative survival following Carpentier-Edwards valve replacement (53 +/- 12% after a 100-month period) did not differ significantly from the estimate following Björk-Shiley valve replacement (80 +/- 6% after a 100-month-period), and subgroups of the cohort did not differ in survival after Carpentier-Edwards or Björk-Shiley valve replacement either. However, the estimate of actuarial cumulative event-free survival following Carpentier-Edwards valve replacement in patients under 40 years of age (46 +/- 14% after a 92-month period) was significantly worse (p less than 0.05) than with Björk-Shiley valves (100 +/- 0% after a 92-month period), (n = 30). The leading cause of clinical complications following Carpentier-Edwards valve replacement was a demonstrable degeneration of the bioprosthesis in 12 cases. The diagnosis of degeneration was established a mean of 73 months postoperatively (range 42-101 months).