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S Mattila

Publications and source records attributed to S Mattila.

At least 37 records · Page 2Linked to original sources
PubMed1996

Abnormal in vivo response to sodium nitroprusside after porcine single lung transplantation.

The chronic increase of pulmonary vascular resistance after lung transplantation is only partly due to an active increase in baseline vasomotor tone, but the nature of the acute pulmonary hypertension after ischemia and reperfusion is not known. We studied the effects of sodium nitroprusside on pulmonary hemodynamics during reperfusion in porcine left lung allotransplants. In twelve pigs (weight: 18 to 24 kg) pulmonary arteries of the native and the transplanted lung were cannulated for right-heart bypass. The total blood flow was 2 L/min. Flow distribution between the lungs was measured at equal mean pulmonary artery pressure, and pulmonary vascular resistance at equal and constant flow-i.e., 1 L/min to each lung. After baseline measurements sodium nitroprusside (1, 3, and 9 microg/kg/min) was administered to six animals (SNP group). The control group (n=6) received an equal amount of the vehicle. After 30 min of discontinuation of the drug infusion, the schedule was repeated. In the transplanted lung, pulmonary vascular resistance decreased in all animals during the first hour of reperfusion. During the second drug infusion pulmonary vascular resistance was significantly lower in the SNP group compared with the control group only at the highest infusion rate of the drug (9 microg/kg/min), which also induced a 44% decrease in systemic vascular resistance. Arterial oxygen tension remained comparable in the two groups throughout the study. Our data suggest that other factors besides active vasoconstriction may contribute to the acute increase of pulmonary vascular resistance after lung transplantation.

Animals↗
PubMed1996

Thromboxane receptor blockade does not attenuate pulmonary pressor response in porcine single lung transplantation.

BACKGROUND: The ischemia-reperfusion lung injury is characterized by increased pulmonary vascular resistance, edema, and subsequent deterioration of oxygenation. Other models of acute lung injury suggest that thromboxane A2 may contribute to the pulmonary hypertension after transplantation. METHODS: We studied the effects of the selective thromboxane A2 receptor antagonist SQ 30741 on pulmonary hemodynamics and gas exchange in porcine single lung transplantation using extracorporeal circulation (right heart bypass) with separate cannulations of the right and left pulmonary arteries. Pulmonary vascular resistance was measured at equal and constant flow to each lung. Flow distribution between the lungs was registered at equal pulmonary artery pressures. Twelve pigs (weight 17 to 23 kg) were studied. At the onset of reperfusion a bolus dose of the drug (5 mg/kg) was injected into both pulmonary arteries followed by an infusion (5 mg/kg/hr) for 1 hour (SQ group, n = 6). The control group (n = 6) received an equal amount of vehicle. The systemic and pulmonary hemodynamics and blood gas values were registered during 2 hours of reperfusion. RESULTS: The pulmonary vascular resistance of the transplanted lung was significantly higher compared with the native lung (p < 0.001). Administration of SQ 30741 failed to ameliorate the pulmonary pressor response of the graft in comparison with the control group. No difference was found in the systemic arterial oxygen tension between the two groups. CONCLUSIONS: Thromboxane does not seem to be among the principal mediators in the pulmonary hypertension after transplantation.

Animals↗
PubMed1996

Cytomegalovirus infection associated accelerated heart allograft arteriosclerosis may impair the late function of the graft.

Cardiac allograft arteriosclerosis is the most important limiting factor of long-term survival of heart transplant recipients. Several clinical studies have suggested the association between CMV infection and heart allograft arteriosclerosis, chronic rejection. To determine the temporal impact of CMV infection on the development of heart allograft arteriosclerosis we quantitated coronary angiograms obtained from 72 heart transplant recipients followed for 1-6 yr post-transplantation. To examine the graft function, echocardiography was evaluated. CMV infection was associated with early development of allograft arteriosclerosis manifested by intense diffuse pruning of the coronary arteries including their smallest branches already after the second post-transplant year. Even 6 yr post-transplantation the magnitude of arteriosclerotic changes was significantly higher in recipients with CMV infection compared with patients without infection (P < 0.02). No difference in echocardiographic parameters including ejection fraction (EF), left ventricular end diastolic diameter (LVEDD) and left ventricular mass (LVM) between recipients with and without CMV infection was recorded early after transplantation. However, when compared to recipients without CMV, the CMV accelerated chronic rejection seen in coronary angiography associated with impaired late graft function as judged by decreased EF in patients with CMV infection 6 yr post-transplantation (P < 0.02). No differences in LVEDD or LVM between the patient groups occurred. Taken together, these results suggest that CMV infection is associated with intense cardiac allograft arteriosclerosis affecting the whole coronary tree soon after transplantation. The intensity and magnitude of these chronic vascular wall changes increase and persist during subsequent years, indicating that the risk for graft loss and death due to chronic rejection is especially high during the first 5 post-transplant years in CMV-infected patients. Echocardiography may not be a sensitive method to distinguish patients with early CMV-accelerated allograft arteriosclerosis but coronary angiography must be performed.

Acute Disease↗
PubMed1995

Results of cardiovascular surgery in the Marfan syndrome. A retrospective study of 49 patients.

To evaluate the outcome of cardiovascular surgery in the Marfan syndrome, the records of 49 patients (median age 35 years) who underwent 60 operations were reviewed. Primary surgery was elective in 39 patients and emergency in ten. Non-dissecting aneurysm with diameter 4-19 cm was present in 34 cases and distal, isolated aneurysm in four. In eight cases there was type A acute aortic dissection with median diameter 5.0 cm. One patient was operated on for mitral valve insufficiency, one for ventricular septal defect and one (acute) for endocarditis. Composite grafts were used for aortic root reconstruction. Operative complications occurred in 24% of the patients. The 30-day survival was 92%. There were five (10%) late deaths. Survival after a median of 8 years postoperatively was 82%. The early and late results of cardiovascular surgery in the Marfan syndrome thus are concluded to be generally favourable. As late reoperation frequently is needed, however, close monitoring is advocated even after successful primary surgery.

Adolescent↗
PubMed1995

Barrett's oesophagus and perforation of gastric tube ulceration into the pericardium: a late complication after reconstruction of oesophageal atresia.

15 years after replacement of atretic segment with a gastric tube, perforation of an intrathoracic gastric tube ulcer into the pericardium, oesophago-pericardial fistula and severe mediastinitis developed in a 17-year-old male after reconstruction of oesophageal atresia using a retrosternal Heimlich-tube with a cervical oesophagogastric anastomosis. For six years he suffered from reflux oesophagitis and had Barrett's metaplasia in the cervical oesophagus. The patient had previously had one unsuccessful attempt to correct the oesophageal atresia at the age of two years using transverse colon. The two stage treatment included subtotal oesophagectomy, pericardiotomy, cervical oesophagostomy, gastrostomy, mediastinal and pericardial irrigation with antibiotics. After healing of the mediastinitis, the continuity of the alimentary tract was restored by using an isoperistaltic subcutaneous ileocolic segment. After a follow-up of five years the patient is well, without any oesophageal symptoms.

Adolescent↗
PubMed1995

Comparison of long-term survival after repair of ruptured and non-ruptured abdominal aortic aneurysm.

Late survival rates were compared and analysed for 1070 patients undergoing repair of ruptured infrarenal abdominal aortic aneurysm (RAAA, n = 364, mean age 70.0 years, male:female ratio 5.6:1) and non-ruptured abdominal aortic aneurysm (AAA, n = 706, mean age 66.6 years, male: female ratio 5.4:1) between January 1970 and July 1992 at the Department of Thoracic and Cardiovascular Surgery of Helsinki University Central Hospital, Finland. There was a statistically significant difference in survival rates between the RAAA and AAA groups during the first three months after repair of abdominal aortic aneurysm. Operative mortality rates were 7.4% for electively repaired abdominal aortic aneurysms and 48.7% for ruptured abdominal aortic aneurysms. For 3-month postoperative survivors there existed no statistically significant difference in late survival rates, nor did these rates differ from those of an age- and sex-matched population. Five-year survival rates for 3-month postoperative survivors were 60% in the RAAA group and 67% in the AAA group. Median survival time was 5.7 years and 7.5 years, respectively. Coronary artery disease, hypertension, chronic obstructive pulmonary disease and renal insufficiency statistically significantly reduced late survival rates after 3 months post-surgery for non-ruptured abdominal aortic aneurysm, whereas these risk factors did not alter late prognosis after successful repair of ruptured abdominal aortic aneurysm. Cerebrovascular disease reduced late survival rates both in AAA (median survival time 6.3 years) and RAAA group (median survival time 4.9 years). Of late deaths 41% were caused by coronary artery disease in the AAA group and 38% in the RAAA group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Frequency of infections and their relation to episodes of acute rejection among heart allograft recipients.

OBJECTIVES: Infections and episodes of acute rejections are major factors affecting allograft survival during the first year after transplantation. The frequency of infections, and the relation of injections to rejection episodes were studied among heart allograft recipients with the follow-up time one year. METHODS: The study population consisted of 58 patients receiving a heart allograft through 1985 to 1990. Low-dose triple-drug therapy was used for immunosuppression, and rejections were treated either with methylprednisolone, antithymocyte globulin, or the combination of methylprednisolone and antithymocyte globulin. The patients received 2 g of vancomycin i.v. 2 days postoperatively, and no further antibacterial prophylaxis was used. The diagnosis of infection was based on clinical symptoms and on microbiological or serological demonstration of an infection. When the correlations between severe infections and rejections were examined, only infections occurring within 1 month from the onset of the rejection were included. Chi-square test was used for statistical analysis. RESULTS: Seventy-nine infections were registered (1.6 +/- 1.4 episodes/patients); 74% of the patients underwent at least one infection episode. Most infections, 61% (49), occurred during the first three posttransplant months, cytomegalovirus and bacterial agents accounting for the most important aetiology. No difference in the overall infection frequency existed between the patients with or without rejections. Twenty seven infection episodes were recorded in 18/50 patients with rejections (p = NS), 11 of them in relation to rejection in 5/18 patients. The frequency of infections after antirejection therapy either with antithymocyte globulin or the combination of methylprednisolone and antithymocyte globulin (7/11) was higher than with methylprednisolone alone (4/20) (p < 0.05). Infections were the primary cause of death in 50%. The rest of deaths were caused by acute rejections. CONCLUSION: There was a typical pattern of infections occurring mainly during the first three months after transplantation, and a significant tendency towards severe infections after intense antirejection therapy with antithymocyte globulin.

Acute Disease↗
PubMed1993

Prosthetic bifurcation grafting in occlusive and aneurysmal aortoiliac disease--a follow-up study.

A comparative clinical study was made of patients undergone prosthetic bifurcation grafting for non-ruptured abdominal aortic aneurysm n = 135 or aortoiliac occlusive disease n = 180 between January 1982 and December 1986. Patients in aneurysmal group were older, predominantly men, had hypertension more often and had better distal run-off at the time of operation. Smoking was over-presented among aortoiliac occlusive disease patients. Patients operated for abdominal aortic aneurysms had better early and late graft patency rates and lower late amputation rates. There were no significant differences in operative mortality rates and late survival rates between occlusive disease and aneurysmal patients. Cardiac mortality mainly reduced early and late survival rates in both patient groups. We should begin to use systematically a reliable and non-invasive method for screening the myocardial status in patients who are going to be operated for abdominal aortic aneurysm or aortoiliac occlusive disease.

Adult↗
PubMed1992

Long-term blood flow potentials in sequential internal mammary artery grafts. Exercise thallium scan for myocardial perfusion study.

In two groups of patients, coronary artery bypass surgery for angina pectoris included internal mammary artery (IMA) sequential grafts (group I) or single grafts (group II). At postoperative angiography all grafts were patent. In addition, the patients received on average 1.8 vein grafts into other coronary arteries. The mean interval to postoperative follow-up was 9.5 years in group I and 9.7 years in group II. The preoperative incidence of acute myocardial infarction was 44% and 45% in groups I and II. Exercise thallium scan at follow-up showed IMA graft-related ischemia in 33% of the patients with sequential graft and in 64% of those with single graft (ns). Our results indicated that sequential IMA grafts functioned at least as well as single grafts and maintained adequate myocardial supply even 10 years postoperatively. Internal mammary arteries are superior graft material and can be recommended both as single and as sequential graft in coronary artery bypass surgery.

Aged↗
PubMed1992

Peripheral excimer laser-assisted angioplasty. Preliminary clinical experience.

A non-thermal Xenon-Chloride excimer laser was used for peripheral arterial recanalization in eight patients with obliterating atherosclerosis of the superficial femoral artery. All patients had a total occlusion with severe claudication or pain at rest. There were three complications, which all led to thrombosis of the irradiated artery. In one, the puncture site in the artery had to be closed operatively. All vessels were followed up radiographically three months after the procedure. In seven patients the vessel was patent. Several investigators have warranted caution in using thermal lasers (continuous wave Nd:YAG or argon) for angioplasty. The non-thermal excimer laser is a viable alternative--although not without problems. Initial experiences with the new device are described.

Aged↗
PubMed1991

Cytomegalovirus myocarditis in transplanted heart verified by endomyocardial biopsy.

Cytomegalovirus infections are common disorders after heart transplantations. Manifestation of the virus without a clinical disease is still more prevalent. Differentiation of clinical infections from cytomegalovirus activations without major pathogenetic importance issues a challenge in the follow-up of patients with cardiac transplants. The case describes a 56-year-old female patient with a multiple organ lethal infection and myocarditis due to cytomegalovirus diagnosed during life with endomyocardial biopsy.

Biopsy↗