Search PubMed⌕ Search

Biomedical subjects

S Mattila

Publications and source records attributed to S Mattila.

At least 91 records · Page 5Linked to original sources
PubMed1985

Effects of synthetic blood and crystalloid cardioplegic solutions on coronary endothelium: an experimental scanning electron microscope study.

In an experimental study the effects of Fluosol DA (added with potassium chloride) on the vascular interface and endothelial cells were compared to those of crystalloid potassium cardioplegic solution using scanning electron microscope. Twenty rabbits (10 in each group) were sacrificed, the hearts with ascending aorta were immediately excised, and cold oxygenated solution was infused via a cannula inserted into the cross-clamped aorta. The hearts were left immersed in the perfusion medium for 2 hr. In the Fluosol DA group endothelial cover and endothelial cells were normal or minimal changes were seen in seven cases. Occasional breaking of intercellular attachments, small areas of denuded flow surface, and disappearance of microvilli were seen in three cases. In the crystalloid potassium cardioplegic group 7 of the 10 cases showed moderate or severe damage with large areas of denuded flow surface. The present experimental protocol represented an extreme situation where no collateral coronary blood was present. The coronary endothelial damage was obvious after the crystalloid potassium cardioplegic solution. Similar damage was not found following Fluosol DA infusion.

Animals↗
PubMed1985

Pacemaker infections--treatment with total or partial pacemaker system removal.

During the years 1977 to 1983, 1,458 pacemakers were implanted or reimplanted in our clinic. Seventy-nine patients were treated during the same period for pacemaker system infections. The time interval between the preceding surgical maneuver and the manifest infection was 11.9 +/- 10.2 months in the catheter fistulas and 12.2 +/- 11.5 months in the pacemaker pocket infections. Forty-one of 79 infections (52%) occurred following the first generator implantation. In 33/43 (76.7%) patients with partial pacemaker system removal, recurrent infection occurred 19.6 +/- 17.2 months later. The infection was treated with similar surgical maneuvers resulting in subsequent infections in 9 patients after 9.8 +/- 7.2 months. In the patients with total pacemaker system removal infection developed in 2/25 (8%). The infection resulted in septicemia in 9 patients. Major surgical intervention was necessary for removal of the infected endocardial electrode in 7 patients. According to our experience there are no grounds for partial removal of the pacemaker system if infection occurs. The primary results may be satisfactory but re-infection will appear in the majority of the patients after a period of several months.

Follow-Up Studies↗
PubMed1985

Auscultatory and echophonocardiographic characteristics of the normally functioning Medtronic-Hall aortic valve prosthesis.

We recorded auscultatory and echophonocardiographic findings in 30 patients who had a normally functioning Medtronic-Hall (M-H) tilting disc valve prosthesis in the aortic position. The opening and closing sounds were invariably audible. Echophonocardiography showed that a typical opening sound consisted of 2 or 3 sharp clicks which were related to the onset and termination of the disc opening excursion. The closing sound comprised at least 2 separate clicks which coincided with the onset and completion of the valve closure. An early systolic ejection type murmur was heard in 25 patients and a faint early diastolic murmur in 2. The disc motion could be recorded echocardiographically in 27 patients. The opening amplitude of the disc varied from 3 to 11 mm. The intervals from the Q wave and the first heart sound to the onset of valve opening measured 116 +/- 20 ms (mean +/- standard deviation) and 54 +/- 14 ms, respectively. The opening and closing velocities of the disc were also easily measurable but showed a wide patient-to-patient variation. In 5 patients, the examination was repeated after 8 to 12 months. The reproducibility was excellent for the auscultatory findings and fair for the echophonocardiographic time intervals and disc opening amplitude, but poor for the disc velocities. Familiarity with these normal findings should help clinicians to determine whether an aortic M-H valve functions normally or not.

Adult↗
PubMed1985

Removal of monofilamental and multifilamental temporary pacing leads following open-heart surgery: occurrence of arrhythmias.

This study compared multifilamental and monofilamental temporary pacing leads in a clinical series of 83 patients who underwent valve replacement or coronary artery bypass grafting. The leads were used in the bipolar mode and were implanted into the outer layers of the right ventricular myocardium. The force required for wire removal (newtons), and the arrhythmias which occurred during removal were monitored. During electrode removal, 48% of the patients had transient arrhythmias (46% with monofilamental and 51% with multifilamental leads). The most common was a single ventricular premature contraction. In one case, wire removal caused non-sustained ventricular tachycardia. All the arrhythmias subsided spontaneously. There was no statistical difference between results of the two leads. The force needed for removal was monitored directly by applying force via a graduated spring; they were equal in both groups (2.6 newtons). Both electrode types behaved similarly during wire removal, and the spiral tail of the monofilamental lead did not provoke arrhythmias.

Adult↗
PubMed1985

Combined heart and lung autotransplantation and regulation of breathing.

The effects of en bloc autotransplantation of the heart and both lungs on the regulation of breathing were studied in four mongrel dogs. Tidal volume, respiratory rate, airflow, airway pressure and electromyograms from the intercostal muscles and diaphragm were recorded before and after the transplantation. The dogs breathed air or a mixture of 5% CO2 and air. Airway closure at functional residual capacity (FRC) level and after insufflation of 200 ml air was used as a mechanical stimulus. The following observations were made. 1) Stimulation by 5% CO2 after the transplantation increased the ventilatory minute volume by increasing the tidal volume while the respiratory rate remained unaltered. Before transplantation, both tidal volume and respiratory rate increased in response to CO2 stimulation. 2) After transplantation, stretching of the airways did not cause apnea (Hearing-Breuer reflex abolished) as it did preoperatively. 3) CO2 inhalation increased the efficiency of the respiratory muscles as expressed by the ratio of mechanical work (tidal volume or pressure impulse) to electrical activities of the respiratory muscles. This was most obvious in the dogs with transplant when the airways were closed at FRC level. Elimination of the afferent impulses due to en bloc transplantation of the heart and both lungs therefore modified the efferent impulses to the respiratory muscles. This effect was seen after both chemical and mechanical stimuli.

Animals↗
PubMed1985

Cardioplegic protection with hypothermic K-Fluosol DA and K/Mg-Fluosol DA solutions.

Oxygenated fluorocarbon cardioplegic solution was tested in 20 isolated rabbit hearts. In 10 of the hearts, 150 ml of solution (Fluosol DA) with addition of 20 mmol/l potassium, 4 degrees C, was infused during 3 min into the aortic root (infusion pressure 60-80 mmHg). The other 10 hearts were perfused with Fluosol DA containing 20 mmol/l potassium and 15 mmol/l magnesium. The hearts were left immersed in the perfusion solution for 2 hours. Myocardial biopsies were performed while the hearts were still beating, immediately after completion of the cardioplegic infusion and 60 and 120 min later. Transmission electron microscopy showed progressive, time-related deterioration of the myocardial cells, characteristic of myocardial ischaemia, in both groups. The changes, however, were clearly less pronounced in the K/Mg-Fluosol DA group. Myocardial capillaries remained patent in both groups throughout the observation period, but the capillary endothelium was better preserved in the K/Mg-Fluosol DA group. The study thus indicated that K/Mg-Fluosol DA was superior to K-Fluosol DA as a cardioplegic agent in terms of ultrastructural preservation of the myocardial cells and the endothelial lining of the myocardial capillaries.

Animals↗
PubMed1985

Repair of ventricular septal defect in adults.

To evaluate the outcome of ventricular septal defect (VSD) with long duration of haemodynamic derangement, a retrospective study was made of 42 consecutive patients who underwent closure of VSD as adults (age range 15-48, mean 27 years). The mean systolic pulmonary arterial pressure was 53 mmHg, mean pulmonary vascular resistance 2.5 Wood units and mean pulmonary/systemic flow ratio 2.4. VSD was complicated by aortic regurgitation in 12 cases, mitral regurgitation in 4, and sinus of Valsalva fistula in 6 cases. There were 15 supracristal, 24 infracristal and 3 muscular VSDs. In addition to VSD closure, surgery included aortic valve replacement (7 cases), mitral valve replacement (2), valve repair by suture (7) and repair of Valsalva sinus fistula (6 cases). Two patients died in the early postoperative period and two during follow-up (1-10, mean 4.5 years). The early and the late mortality were related to large infracristal VSD, pulmonary hypertension and irreversible pulmonary vascular changes which could not be anticipated on the basis of high calculated shunt flow at preoperative catheterization. No patient with supracristal VSD died. Recurrent VSD was diagnosed in five patients, three of whom needed reoperation and recovered uneventfully. Reduction of heart size and improved exercise tolerance were the most pertinent follow-up findings. The results suggest that large supracristal VSD with aortic valve involvement can be successfully closed in adults, but that the prospect for large infracristal VSD is less favourable if correction is postponed until adulthood.

Adolescent↗
PubMed1985

Combined multiple-valve procedures. Factors influencing the early and late results.

The early and late results were retrospectively evaluated in 57 cases of double or triple valve replacement or repair performed in 1970-1983. The causes of the valvular lesions were rheumatic fever (43 cases), bacterial endocarditis (6), syphilis (1) and unknown (7 cases). The preoperative NYHA classification was III in 29 patients and IV in 28, due mainly to dyspnea of effort. Cardiomegaly (mean radiologic volume 880 cm3/m2) and atrial fibrillation were the dominant clinical findings. Surgery was on emergency indications in five cases. Cold cardioplegia combined with external cardiac cooling has been used for myocardial protection since 1977. The valve replacements were 56 aortic, 50 mitral and 2 tricuspid. In addition there were three closed and two open mitral commissurotomies, two mitral plastic repairs, three tricuspid valve anuloplasties (DeVega) and one aortic anuloplasty. Follow-up (0.3-13, mean 3.5 years) was supplemented with a check-up including two-dimensional echophonocardiography and hematologic tests. The operative mortality (10/57 patients) fell from 26% in 1970-1976 to 12% in 1977-1983. The causes of death were low cardiac output in preoperatively ill patients (5), myocardial infarction (2), technical failure (2) and sepsis (1 case). There were 11 late deaths (6.7/100 patient-years of observation), the commonest cause (5 patients) being congestive heart failure. The respective incidences of thromboembolism, paravalvular leak and postoperative endocarditis were 2.1, 4.2 and 2.1 episodes/100 patient-years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Experience with single photon emission computerized tomography (SPECT) in follow-up of sternotomy healing.

Single photon emission computerized tomography (SPECT) was performed thrice in ten patients undergoing open-heart surgery--preoperatively and 2 and 12 weeks postoperatively. The operations were done for ischemic heart disease (5), aortic valvular stenosis (2), aortic valvular insufficiency (1), leaking mitral prosthetic valve (1) and combined aortic and mitral valvular stenosis and insufficiency (1). The healing process in the longitudinally divided sternum was evaluated from the SPECT study. Four conventional static images in two dimensions were registered in anteroposterior, posteroanterior and left and right lateral projections. A tomographic study was done. Quantitative analyses were performed. The ratio of the sternal counts to the counts from a thoracic vertebra was calculated for use as a reference. The activity ratios showed a similar pattern in six cases, with initial increases and at 12 weeks slight decrease compared with the preoperative values. In two cases the activity was still increasing after 12 postoperative weeks. One patient, with sternotomy also one year previously, showed only slightly increased activity. The activity at the areas of the sternal wires was increased in six cases. The study thus revealed differing patterns of isotope uptake, although recovery was uneventful in all patients. The differences may reflect the possibility that the operative course and the preoperative clinical status can influence the healing mechanisms.

Adult↗
PubMed1985

Results of surgical treatment of synchronous multiple primary lung carcinomas.

Four male patients with synchronous multiple lung carcinoma were operated on. In one patient both tumours were adenocarcinomas; both were bronchioloalveolar carcinomas in a second patient. In a third patient the tumours were adenocarcinoma and bronchioloalveolar carcinoma while in the fourth patient an adenocarcinoma and a squamous cell carcinoma were present. One patient was asymptomatic and free from carcinoma at follow-up examination 11 years and 7 months after the operation. The other three died of pulmonary carcinoma 11 months, 1 year 3 months and 9 years 8 months postoperatively.

Adenocarcinoma↗
PubMed1985

Tumour growth rate and its relationship to prognosis in bronchiolo-alveolar and pulmonary adenocarcinoma.

Tumour growth rates and their effects on the survival of 26 patients with bronchioloalveolar or pulmonary adenocarcinomas were analysed following surgery. Twelve of the tumours were classified as bronchioloalveolar carcinomas, 7 were classed as mixed forms of bronchioloalveolar carcinoma and 7 were classed as adenocarcinomas. The mean doubling time was 300.1 days for the bronchioloalveolar carcinomas, 288.4 days for the mixed forms of bronchioloalveolar carcinoma and 224.6 days for the adenocarcinomas. The mixed forms of bronchioloalveolar carcinoma had poorer prognoses than bronchioloalveolar carcinomas. They also differed from adenocarcinomas in that metastases were more frequent. No correlation between tumour doubling times and patient survival was established in the present series, nor did tumour doubling times correlate with the occurrence of metastases in regional lymph nodes. The actual survival times were similar to, or shorter than, predicted survival times in most of the patients who died from their pulmonary carcinoma. In contrast, they were considerably longer than predicted survival times in long-term survivors and in half of the patients who did not die from pulmonary carcinoma. This finding indicates that predicted survival times could allow more objective evaluation of the results of treatment of pulmonary carcinoma.

Adenocarcinoma↗
PubMed1985

Surgical treatment of metachronous primary lung carcinomas.

Eleven patients were operated on for metachronous primary lung carcinomas. Most patients were heavy smokers. The incidence of primary metachronous carcinomas suitable for the operation was 0.45% of primary lung malignancies operated on during the same period. The mean interval between the first and second operations was 47.3 months. Surgical mortality was 0 after the first operation and 18% (2 out of 11 patients) after the second operation. The second primary malignant tumours were more advanced than the first ones. Two patients were alive at the follow-up 9 and 52 months after the second operation. The cause of the death was pulmonary carcinoma in five patients and respiratory and renal failure in one patient and respiratory insufficiency in one patient. Our findings suggest that reoperation for second primary lung malignant tumours should only be performed if the diagnosis is established early enough and if the primary operation was considered to be radical.

Adenocarcinoma↗
PubMed1985

Effects of mitral valve replacement on ventilation, volumes, diffusing capacity and regional perfusion of lungs in patients with mitral valve disease.

The effects of mitral valve replacement on ventilation, lung volumes, diffusing capacity and regional perfusion of the lungs were studied in eight patients with long-standing mitral valve disease. Eight patients of the same age with coronary artery disease who underwent coronary bypass operation were tested as controls. Preoperatively, the patients with mitral valve disease had significantly higher perfusion of the upper lung fields and the ratio of residual volume to total lung capacity than the control patients. Vital capacity, forced expiratory volume in one second and maximal expiratory flow at 50% of vital capacity were lower in comparison with the control group. Seven days after open heart surgery the values of all the parameters mentioned above had decreased significantly from the preoperative levels in both groups. Three months post-operatively, the values returned to preoperative levels. The abnormal overperfusion of the upper lung fields and other derangements in the ventilatory pattern did not subside even though cardiac haemodynamics were corrected by mitral valve replacement.

Adult↗
PubMed1985

Neurological events in cardiac surgery.

Fifty consecutive coronary artery bypass grafting (Group I) and 50 single valve replacement (Group II) procedures were compared with 50 coronary artery bypass grafting with valve replacement (Group III) procedures and 50 multi-valve procedures (Group IV) to determine the frequency of neurological complications after cardiopulmonary bypass (CPB). The possible risks and aetiological implications were studied. The overall surgical mortality rate was 7.5%, being 0%, 4%, 6% and 20%, respectively for the different groups. The neurological event was not the primary cause of death in any of the patients. After CPB, neurological manifestations occurred in 4% of the patients in Gr. I, in 6% in Gr. II, in 4% in Gr. III, and in 8% in Gr. IV. Three patients had peripheral nerve paresis. The age of the patients and the duration of the CPB operation were not factors in the risk of neurological complications. Previous neurological events seemed to increase the frequency of postoperative neurological disorders, whereas combined procedures were no more dangerous in this respect.

Adolescent↗
PubMed1984

Endothelial cell damage following crystalloid cardioplegic solution infusion. Scanning electron microscope study of coronary bypass grafts.

Scanning electron microscope studies of coronary bypass grafts were carried out in six routine bypass operations. Infusion of the initial crystalloid cardioplegic medium into the aortic root after aortic cross clamping was performed in every case. In two cases, pieces of aorta below and above the cross-clamped site, le, having and not having had contact with the crystalloid cardioplegic medium, were studied. The endothelial lining of the veins showed normal structure following distention with blood. Following infusion with a crystalloid cardioplegic solution, the endothelial cells had almost completely vanished and the flow surface was composed mainly of collagen fibers. The aortic samples taken from below the cross-clamp site showed similar destruction of the endothelium that was observed in vein grafts after crystalloid cardioplegic solution infusion, whereas the aortic samples taken from above the cross-clamp site disclosed normal endothelium.

Aorta↗
PubMed1984

Cardiac tamponade and different modes of artificial ventilation.

Cardiac tamponade after open-heart surgery often occurs in a situation when the patient is still mechanically ventilated and needs circulatory support with catecholamines. To evaluate the effects of different modes of artificial ventilation and dopamine on cardiac tamponade, an experimental study was carried out in seven mongrel dogs. In pentobarbital - N2O anaesthesia, a cardiac tamponade of 20 mmHg was produced by injecting 120-200 ml of normothermic saline into the pericardium. Intermittent positive pressure ventilation (IPPV) and positive end-expiratory pressure (PEEP) ventilation with frequencies of 12 and 20 were tested before and after producing the tamponade. Cardiac tamponade produced a significant fall in arterial pressure and cardiac output, a significant rise in central venous pressure and only a slight increase in pulmonary arterial pressure. PEEP with the slower ventilation frequency of 12 produced additional, significant falls in cardiac output and systemic arterial pressure, which were not noted with the ventilation frequency of 20 and PEEP. Dopamine infusion increased the cardiac output by increasing the heart rate during tamponade. It is concluded that PEEP ventilation with a slow frequency should not be used if cardiac tamponade is suspected after open-heart surgery, and that dopamine has a favourable effect on haemodynamics even in the presence of a severe cardiac tamponade.

Animals↗