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O Lund

Publications and source records attributed to O Lund.

At least 55 records · Page 3Linked to original sources

Fourteen-year experience with homovital homografts for aortic valve replacement.

Two hundred seventy-five unprocessed, viable homograft ("homovital") aortic valves were used for aortic valve replacement in patients aged 1.5 to 79 years (mean 45.8 +/- 19 years) with maximum follow-up of a 14-year period (mean 4.8 years). Ninety-two percent (252 patients) had New York Heart Association class III or IV functional status before operation and 25 underwent emergency operation. Valves were harvested under sterile conditions and kept in nutrient medium 199. Freehand (subcoronary) technique was used in 147 patients and freestanding root replacement was used in 128. Cumulative survival rates for the whole group were 92% +/- 2% at 5 years and 85% +/- 3% at 10 years, as compared with 96% +/- 2% and 94% +/- 4%, respectively, for the 98 patients who underwent isolated root replacement. Multivariate analysis determined that root replacement with associated procedures and operation for prosthetic endocarditis were risk factors for death, whereas previous xenograft valve, operation for endocarditis, and operation for aortic regurgitation were risk factors for reoperation. Actuarial rates for freedom from degenerative valve failure diagnosed at operation, by postmortem examination, or by routine echocardiography were 94% +/- 2% at 5 years and 89% +/- 3% at 10 years. Recipient age younger than 30 years and previous xenograft valve were risk factors for late degeneration. We conclude that homovital valves demonstrate good durability, particularly in patients older than 30 years, who had a 10-year freedom from degeneration rate of 97%.

Adolescent↗

Increased adhesion as a mechanism of antibody-dependent and antibody-independent complement-mediated enhancement of human immunodeficiency virus infection.

Enhancement of human immunodeficiency virus (HIV) infection by complement alone or in conjunction with antibodies was studied experimentally and theoretically. Experimental studies showed that while HIV-positive sera neutralize HIV infection, the addition of fresh complement abrogated neutralization and could even cause enhancement. Enhancement was blocked by anti-complement receptor 2 antibodies, and infection under enhancing conditions could be blocked by soluble CD4. Antibody-dependent complement-mediated enhancement (C'ADE) was dependent on the alternative complement activation pathway, as factor B-deficient serum could enhance only after the addition of factor B. The observed enhancement was also antibody dependent, since the addition of antibodies increased the level of enhancement. Under C'ADE conditions, infection reached a plateau within 5 min and was not caused by activation of cells by factors in the human serum. On the contrary, preincubation of cells with complement decreased the level of enhancement. A theoretical model of HIV infection in vitro which exhibited similar enhancement in an antibody- and complement concentration-dependent way was developed. Model studies indicated that the enhanced infection process could be explained by the fact that virions, because of complement deposition on the surface, bind more efficiently to cells. The model also indicated that the saturation of the enhanced infection process seen after a few minutes could be caused by saturation of the complement receptors. The effect of neutralizing antibodies can thus be overcome by the enhancing effect of complement that facilitates the contact between gp120 and CD4. These studies demonstrate that the main features of the complement-dependent enhancement phenomenon can be understood in terms of a simple mathematical model.

CD4 Antigens↗

Right internal mammary artery for myocardial revascularization: early results and indications.

The right internal mammary artery (RIMA) was used for coronary artery bypass grafting in 258 patients from October 1985 to October 1991. The RIMA was inserted as the only graft in 8 patients and in combination with the left internal mammary artery (LIMA) in 231 patients, the right gastroepiploic artery in 19, and autologous vein in 184. The patients received a total of 1 to 8 distal anastomoses (mean number, 3.3). A total of 64% of the RIMAs were anastomosed to the left anterior descending coronary artery. The primary indication for use of the RIMA was small-vessel disease in 86 patients, repeat bypass grafting in 32, varicose or stripped saphenous veins in 61, and "selected routine case" in 79. The early (< or = 30 days postoperatively) mortality rate in these four groups was 8.1%, 6.3%, 0%, and 0%, respectively (p < 0.01). Independent risk factors (logistic regression analysis) for early mortality were small-vessel disease, insufficient grafting, repeat coronary artery bypass grafting, diabetes, history of smoking, age of 60 years or older, and family history of ischemic heart disease. Combined into a risk index, these risk factors identified six risk groups with early mortality of 0% in the four low-risk groups and 5.6% and 58.3% in groups V and VI, respectively (p < 0.0001). No RIMA-related variables were risk factors for significant postoperative myocardial enzyme release. Intraoperative electromagnetic flow measurements revealed no differences between the RIMA and LIMA. Early angiographic patency in 50 patients was 98% for the RIMA and 93% for the LIMA.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Circulation↗

Multiarterial coronary artery bypass grafting with special reference to small vessel disease and results in women.

From 1985 to 1991 a total of 220 patients underwent coronary artery bypass grafting (CABG) with at least two native pedicled artery grafts. Bilateral internal mammary artery (IMA) grafting was performed in 201 patients, IMA combined with gastro-epiploic artery (GEA) grafting in five, and double IMA plus GEA grafting in 14; in addition 156 patients received 1-3 vein grafts. The primary indication for elective multi-arterial CABG was coronary arteries of small calibre (small vessel disease) in 77 patients, repeat CABG in 17 (without small vessel disease), varicose/stripped saphenous veins in 57 (without small vessel disease), while the remaining 69 were routine cases; the distribution differed between women (42, 0, 47, and 11%, respectively) and men (33, 10, 19, and 38%, respectively; P < 0.0001). The women also were older (62 +/- 7 vs 56 +/- 9 years; P < 0.001), and had higher prevalences of systemic hypertension, diabetes mellitus, and hypercholesterolaemia. The number of artery grafts and total number of grafts were, however, similar for women and men. Early mortality (< or = 30 days) was 5.6% in women and 2.4% in men (ns). Early mortalities in relation to primary indications were: 7.8% for small vessel disease, 5.9% for repeat CABG, and 0% for both varicose/stripped saphenous veins and routine cases (P < 0.05). Logistic regression analysis identified small vessel disease, insufficient grafting, age of > = 60 years, a history of smoking, a family history of ischaemic heart disease, and female gender as independent risk factors for early mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Valve replacement for aortic stenosis: the curative potential of early operation.

Concentric hypertrophy of the left ventricular wall is the primary consequence of acquired aortic stenosis (AS). Reduced left ventricular (systolic) function usually returns to normal after aortic valve replacement (AVR) in AS. Afterload mismatch prior to AVR, and not reduced contractility, is thought to be the explanation. Together with "the prosthetic valve disease" the afterload mismatch theory is used conceptually to postpone AVR until severe symptoms prevail. However, latent or manifest myocardial ischaemia/hypoxia is a central abnormality in concentric hypertrophy, also in the absence of coronary artery disease (CAD); impaired left ventricular diastolic function due to both reduced (active) relaxation and passive qualities of hypertrophied muscle is the primary cause of congestive failure symptoms. Reduced systolic function (ejection fraction) develops in succession, and dilation of the ventricle is an end-stage phenomenon. With the present timing of operative intervention significant late excess mortality from congestive heart failure is the rule after AVR in AS. Early functional improvement is probably related to reduced myocardial oxygen demand associated with afterload reduction caused by AVR, irrespective of irreversible myocardial disease. Employing a 22-year surgical series, multivariate predictive models were made for the following effect measures of AVR: early mortality, long term survival, prosthesis related complications, sudden heart related events, recurrence of congestive heart failure, heart pathology at autopsy, and left ventricular systolic and diastolic function 12 years after AVR. A prognostic index was calculated for each patient from variables related to pre-AVR degree of heart disease. A low prognostic index corresponding to operative intervention early in the course of AS predicted an operative mortality approaching zero, a normal sex and age specific long term survival, a normal rate of the quantitatively most important prosthesis related complications, a normal rate of heart related events, complete symptom freedom early after the operation without late return of congestive heart failure, and normal left ventricular function late after the operation. Complete regression of left ventricular hypertrophy was a dominant underlying mechanism. Imparied diastolic function of the left ventricle at late reinvestigation, being related to significant residual hypertrophy, was the sole predictor of fatal congestive heart failure irrespective of (a usually normal) ejection fraction. A policy of consistent coronary artery bypass grafting concomitant with AVR in case of CAD reduced early mortality rate in such patients, including the elderly, to the (low) level of those without CAD. A normal survival can, however, not be anticipated in AS patients with concomitant CAD.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

[Clinical picture of acute pulmonary embolism. Relations to the degree of vascular obstruction].

In 132 consecutive patients treated for pulmonary embolism, duration of symptoms, number of embolic episodes before the diagnosis, circulatory affection (stable circulation (n = 61), reversible shock (n = 60), circulatory collapse (n = 11), electrocardiographic findings and systolic pulmonary pressure (n = 60) were analysed in relation to 1) underlying diseases (orthopedic surgical patients (n = 43), gynecological-abdominal surgical patients (n = 22), preembolic healthy patients (n = 42), miscellaneous medical patients (n = 25)), and 2) the obstruction of the pulmonary vascular bed quantified by a scintigraphic or angiographic score. While embolic score did not differ between the groups of underlying diseases, preembolic healthy patients with deep vein trombosis (n = 30) had longer mean duration of symptoms (14 days), more embolic episodes, (1.7 episode) and higher pulmonary pressure (72 mmHg) than the material on an average with values of 7 days, 0.9 episodes and 57 mmHg, respectively (p less than 0.001). Among patients with reversible shock or circulatory collapse, half had at least one previous embolic episode, one fifth from two to four. Embolic score correlated well with the circulatory affection (p less than 0.001). A high pulmonary pressure correlated with long duration of symptoms and a high number of embolic episodes (p less than 0.002). Sinus tachycardia and electrocardiographic signs of acute right ventricular strain (complete and incomplete right bundle branch block, SIQIIITIII-pattern and inverted T-waves in V2-4) correlated positively to the circulatory affection and inversely to duration of symptoms and number of embolic episodes (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

[Aggressive treatment of acute pulmonary embolism. 132 consecutive patients treated with heparin, streptokinase or embolectomy, 1975-1987].

During 1975-1987, 132 patients were treated for acute pulmonary embolism with heparin (n = 41), streptokinase (n = 52), or embolectomy (n = 39). In 1984, the indications for embolectomy were broadened to include all patients with central emboli, also those who were circulatory stable. The heparin-, streptokinase-, and embolectomy groups differed from each other as regards the degree of circulatory impairment (stable circulation/reversible shock/circulatory collapse: 68/32/0% versus 52/48/0% versus 16/56/28%, p less than 0.0001) and embolic score (20 for complete obstruction; 5.6 +/- 3.4 versus 8.7 +/- 2.8 versus 13.2 +/- 2.4, p less than 0.0001), but were comparable in terms of prognosis (30-day mortality/10-year survival +/- standard error: 7%/61 +/- 9% versus 13%/59 +/- 9% versus 18%/61 +/- 10%). Stable circulation, reversible shock, and circulatory collapse prior to embolectomy resulted in 30-day mortalities of 0%, 9%, and 45% respectively (p less than 0.01). During 1984-1987, no early or late deaths after embolectomy were observed in patients without circulatory collapse (n = 10). In comparable patients (embolic score greater than or equal to 9, symptom duration less than or equal to 7 days, no circulatory collapse), streptokinase treatment (n = 13) and embolectomy (n = 25) resulted in 10-year survival +/- standard error of 46 +/- 16% and 82 +/- 10% respectively (p less than 0.0001) and in an embolic score-reduction (score before minus score after treatment) of 5.7 +/- 2.3 and 10.5 +/- 2.9, respectively (p less than 0.0001). Embolectomy during extracorporeal circulation should be considered the treatment-of-choice in patients with acute central emboli.

Acute Disease↗

[Treatment of spontaneous pneumothorax. Immediate results and cumulative frequency of recurrence].

From 1975 through 1987, 142 patients were treated for their first spontaneous pneumothorax. A total of 745 patient-years (mean 5.2 years, maximum 12.8 years) had been accumulated by June 1988. A total of 32 radiographically verified recurrences were recorded; 72% occurred within the first two years after treatment. The one-, five-, and ten-year cumulative freedoms from recurrence +/- standard error were 88 +/- 3%, 75 +/- 4% and 69 +/- 5%, respectively. The elective duration of tubulation was shortened from 10 to four days; this did not result in a higher complication rate; rather, there was a tendency to a reduced recurrence rate. Placement of the suction tube in 4th-5th intercostal space in anterior axillary line gave a significant greater recurrence rate than placement in 2nd-3rd intercostal space in midclavicular line. Also advanced age, female gender, non-smoking (patients who had never smoked), non-tobaccoabstinence (smokers who did not stop smoking), chronic obstructive lung disease, radiographic emphysema/fibrosis/bullae/blebs and a high height/weight ratio increased the cumulative recurrence rate. The tendency to recurrence after spontaneous pneumothorax showed a characteristic time-related pattern and should be analyzed using an appropriate time-related statistical method. Shortening of elective duration of tubulation may be accomplished without increased complication rate and possibly with a reduction of the cumulative recurrence rate.

Adolescent↗

Thirty-day mortality after valve replacement for aortic stenosis over the last 22 years. A multivariate risk stratification.

Over the last 22 years (1965-86), the 30-day mortality rate (30-DMR) after valve replacement for primary or predominant aortic stenosis (AS, N = 690) fell from 20.0% for the first 100 consecutive patients, via 7.8% for the next 490, to 2.0% for the final 100 (P less than 0.0001). There was, however, a wide scatter in 30-DMR in the 11 consecutive 2-year periods, as well as during later years. The variation in 30-DMR was paralleled by changes in a high risk prognostic index (derived from a logistic regression model) and in a high coronary artery disease (CAD) score. In patients with a high CAD score who died within 30 days, 93% (N = 25) had CAD at autopsy compared with 37% (N = 11) of those with a low CAD score (P less than 0.0001). In 205 patients evaluated by coronary arteriography, the 30-DMR was 4.1% in 122 without CAD, 3.6% (3.8% for triple vessel/left main stem) for 55 with CAD who underwent bypass grafting, and 17.9% for 28 with CAD who did not have bypass grafting (P less than 0.0001). Left ventricular failure (LVF; episodes of pulmonary oedema and/or stasis), age, pronounced hypertrophy/strain in the ECG, and a high CAD score were independent incremental risk factors for 30-DMR. Quantitatively, LVF increased the risk 10 times more than pronounced hypertrophy/strain and a high CAD score. LVF also neutralized the influence of age. Modifying (symptom-masking) digitalis and/or diuretic treatment in functional class II patients (N = 189) increased the 30-DMR from 0.9% to 9.1% (P less than 0.01). The scatter of operative year-specific 30-DMR was related to changes in preoperative prognostic patient profiles and to unrevascularized CAD. Operative intervention in AS patients, even with discrete symptoms, and consistent revascularization of significant CAD, should be strongly advocated.

Acute Kidney Injury↗

Reliability of three computer methods in the analysis of ECG-gated radionuclide left ventriculography: interrecording, interobserver and intraobserver variability.

Three different computer methods for analysis of systolic and diastolic left ventricular function (ejection fraction, peak ejection rate, time to peak ejection rate, peak filling rate, time to peak filling rate, duration of fast filling phase, and fast filling fraction) as derived from ECG-gated radionuclide cardiography were compared in 30 patients with various diseases. The patients had two gamma camera recordings of the left ventricle performed immediately following one another during radionuclide (99mTc) equilibrium (3 x 10(6) counts, 16 frames/cycle, 64 x 64 pixels). Mean ECG R-R interval of the patients remained unchanged from first to second recording. The three computer methods were: (1) end-diastolic (ED) region of interest (ROI) analysis based on manually defined ED-ROI; (2) multi (M) ROI, manually defined ROI for each frame; and (3) semiautomatic (SA) ROI, ROI for each frame defined by an SA edge detection technique. With the 16 frame points as nodes, a 160-point time-activity curve was constructed for each of the three methods by use of a spline function. A tailored multiway analysis of variance showed that the M-ROI method had the highest interindividual range of values of the function parameters and the smallest interrecording, interobserver, and intraobserver variabilities. In theory this implies a better diagnostic sensitivity and specificity for the M-ROI method as compared with the other two methods.

Adult↗

Valve replacement for calcified aortic stenosis in septuagenarians infers normal life-length.

Aortic valve replacement because of pure or predominant stenosis was performed in 1970-1986 on 101 patients aged 70-78 years, including 80 in NYHA function class III or IV. There were 16 deaths within 30 days, and coronary artery disease (unbypassed in all but 1 case) was found in 11 of the 13 with autopsy or preoperative arteriography. None of the 12 patients without significant coronary artery disease at angiography died perioperatively,but one of 12 with combined valve replacement and coronary artery bypass grafting died. Cumulative 1-year survival among the 101 patients/the 85 survivors of the first 30 days and/a normal population matched for sex, age and year of operation was 75/90/96%. Corresponding percentages for 5 years were 64/75/77, for 10 years 43/52/52, and for 15 years 35/42/27. Advanced disease with kidney failure or left ventricular end-diastolic pressure greater than 20 mmHg independently increased the overall mortality rate. The linearized rat of cerebral events (haemorrhage, embolism) was 2.7/100 patient years (age-specific background rate 1.6-1.9/100 patient years). The 30-day mortality among septuagenarians was reduced to 3% in 1988-1989 by routine revascularization in significant coronary artery disease. The patients who survived the first 30 days had normal life expectancy. Early operation may further improve the results.

Aged↗

Prognosis and risk factors in acute, dialysis-requiring renal failure after open-heart surgery.

Of 1988 patients who underwent open-heart surgery from 1980 through 1988, 68 (3.4%) developed postoperative acute renal failure requiring dialysis (2.5% of adult and 8.3% of pediatric patients). Isolated aortocoronary bypass grafting was the operation with lowest incidence of this complication (0.6%). Acute renal failure usually appeared during the first 3 postoperative days. It carried a mortality rate of 63%, with half of the deaths occurring during the first few postoperative days, due to low cardiac output and progressive multiple organ failure. Logistic regression analysis in cases of aortic valve replacement demonstrated that significant independent preoperative risk factors for acute renal failure were renal insufficiency (serum creatinine greater than 110 mumol/l in greater than or equal to 2 samples) and increased cardiothoracic index/left ventricular end-diastolic dimension. Data from the literature indicated no time-related trend towards reduction of acute renal failure incidence or mortality. Prevention of low cardiac output is of major importance in these respects. Operative intervention before development of advanced disease with left ventricular dilatation and secondary kidney failure is advocated.

Acute Kidney Injury↗

Twenty-two-year experience with aortic valve replacement. Starr-Edwards ball valves versus disc valves.

From 1965 through 1986, 817 patients underwent aortic valve replacement at our institution. Six hundred forty-five patients received Starr-Edwards ball valves, including 286 Silastic ball valves (Models 1200/1260), 165 cloth-covered caged-ball prostheses (Models 2300/2310/2320), and 194 track-valve prostheses (Model 2400). In contrast, 172 patients received disc-valve prostheses, including 126 St. Jude Medical aortic bi-leaflet disc valves, 32 Lillehei-Kaster pivoting disc valves, and 14 Björk-Shiley valves (6 convexoconcave and 8 monostrut). With respect to preoperative data, the 2 groups were comparable, with the following differences. The Starr-Edwards group included 1) more men (77% versus 51%; p < 0.0001); 2) a significantly older patient population (59 +/- 10 years versus 56 +/- 15 years; p < 0.0001); 3) more patients in New York Heart Association functional class III or IV (72% versus 65%; p < 0.01); 4) fewer patients with angina pectoris as a limiting symptom (20% versus 36%; p < 0.0001); and 5) patients who tended to receive larger prostheses (26 +/- 2 mm versus 23 +/- 3 mm, p < 0.0001). The overall 10-year survival rate +/- standard error was 59% +/- 2% for patients receiving Starr-Edwards valves and 63% +/- 6% for those with disc valves. The linearized complication rates (expressed as percentage per patient-year +/- standard error) for the Starr-Edwards and disc-valve groups, respectively, were 2.0% +/- 0.2% and 1.4% +/- 0.5% for thromboembolism, 2.1% +/- 0.2% and 3.9% +/- 0.8% for Coumadin-related hemorrhage, 0.5% +/- 0.1% and 0.3% +/- 0.2% for endocarditis, 0.3% +/- 0.1% and 0.7% +/- 0.3% for other prosthesis-related complications, and 4.8% +/- 0.1% and 6.4% +/- 1.0% for all complications together. There were no instances of thrombotic occlusion or mechanical failure. After the 6th postoperative year, no thromboembolic events were encountered in patients with a Silastic ball valve; the 15-year freedom from thromboembolic events was 89%. Cox regression analysis showed that 1) a prosthetic orifice diameter of 15 mm or less was associated with an increased mortality; 2) disc valves entailed an increased rate of hemorrhage and prosthesis-related complications considered as a whole; 3) and Lillehei-Kaster valves led to an increased rate of prosthesis-related complications other than thromboembolism, hemorrhage, and endocarditis. Neither the type of prosthesis nor the size influenced the rate of thromboembolism, endocarditis, or prosthesis replacement. Because of their proven durability and relatively low price, we advocate the continued use of Starr-Edwards Model 1260 Silastic ball valves that have an orifice diameter of 16 mm or more.

Journal Article↗

Independent risk factors for cumulative recurrence rate after first spontaneous pneumothorax.

From 1975 until 1987, 122 patients without (Group I, mean age 34 yrs) and 20 with pre-existing lung disease (Group II, mean age 66 yrs) were treated for their first spontaneous pneumothorax. Mean follow-up was 5.2 yrs (max. 12.8 yrs). There were 32 chest X-ray verified recurrences, 72% occurring during the first 2 yrs. One, 5 and 10 yr cumulative recurrence freedoms +/- standard error in groups I and II combined were 85 +/- 3%, 75 +/- 4% and 69 +/- 5%, respectively. Using Cox regression analysis in groups I and II combined, pulmonary fibrosis, age greater than or equal to 60 yrs, and height/weight ratio were independent predictors of recurrence. Combinations of these risk factors identified four risk strata with 10 yr recurrence freedoms ranging from 83-0%. Independent predictors in group I alone were pulmonary fibrosis, age greater than or equal to 60 yrs, height/weight ratio, and nonsmoking, resulting in four risk strata with 10 yr recurrence freedoms ranging from 98-31%. Recurrences after first-time treated spontaneous pneumothorax showed a distinct time-related pattern and should accordingly be analysed as a time-related event. In both the total patient-population and in the group without pre-existing lung disease, independent predictors of recurrence were identified, which allowed the patients to be substratified into groups with widely different recurrence rates.

Adult↗

[Prosthesis-endocarditis in the aortic position in a 22-year case load. Surgical versus conservative treatment].

During the period 1965-1986, a total of 852 patients underwent isolated aortic valve replacement. With 4,875 patients-years at risk, 24 patients developed prosthetic valve endocarditis (PE; 0.49% per patient-year). The five, ten and fifteen year cumulative freedoms from PE were 98.2%, 95.4% and 93.0%, respectively. PE was unrelated to pre- or intraoperative data. No patients submitted to operation for acute/subacute bacterial endocarditis of the native aortic valve developed PE. Out of the 12 episodes of PE within two years of the operation, seven (58%) were caused by Staphylococcus albus compared with two out of 12 (17%; p less than 0.05) subsequent episodes of PE. Seven of the nine infections with Staphylococcus albus were caused by a highly resistant nosocomial variant. Ten of the PE patients underwent replacement of the prosthesis while 14 were treated conservatively. The two therapeutic groups were comparable, although the surgically treated patients tended to be younger and to have more impaired cardiac status. All surgically treated patients and all patients treated conservatively and in whom post mortem verification was possible had paravalvular defects, annular abscesses and/or vegetations on the prosthesis. The thirty-day, one year and ten year cumulative survivals were 80%, 80% and 50%, respectively, after replacement of the prosthesis and 64%, 21% and 7%, respectively, after conservative treatment (p = 0.02). A Cox regression analysis identified conservative treatment, infection with Escherichia coli or Haemophilus influenzae and the need to intensify digitalis/diuretic treatment for congestive heart failure as independent risk factors. It is concluded that replacement of the prosthesis early in the course of the disease should be considered as the treatment of choice.

Adolescent↗

Long-term prosthesis-related and sudden cardiac-related complications after valve replacement for aortic stenosis.

Predictability of prosthesis-related and sudden cardiac-related complications was examined in 630 patients who were alive 30 days after valve replacement (1965 to 1986) for aortic stenosis. Follow-up totaled 4,072 patient-years. A variety of prosthetic valves, mainly mechanical, were used. The Cox regression model was used to identify independent risk factors and to estimate predicted event-freedoms relative to combinations of these risk factors. There were no risk factors for endocarditis (0.5 +/- 0.1 [number of events per 100 patient-years +/- the standard error]). Except for "other" prosthesis-related complications (0.4 +/- 0.1), adversely influenced by porcine bioprostheses (n = 15) and by the Lillehei-Kaster prosthesis (n = 25), only factors underlying diseased preoperative patient/cardiac status had predictive influence. Predicted 10-year event-freedoms for low-risk versus high-risk estimate were 86% versus 73% for thromboembolism (1.7 +/- 0.2), 95% versus 32% for anticoagulant-related hemorrhage (2.4 +/- 0.2), 69% versus 36% for all prosthesis-related complications (5.0 +/- 0.4), 93% versus 0% for sudden cardiac-related events (myocardial infarction and arrhythmia) (1.8 +/- 0.2), and 66% versus 0.5% for combined prosthesis-related and sudden cardiac-related morbidity and mortality (6.8 +/- 0.4). In 193 patients with coronary arteriography, coronary artery disease was a significant risk factor for each of the complication modalities examined except other prosthesis-related complications, prosthesis replacement, and endocarditis. Deciding to operate early in the course of aortic stenosis might "actively" reduce the rate of these complications.

Adult↗

Improved outcome of coronary arterial bypass surgery in a small center after identification and modification of peroperative risk factors.

By uni- and multivariate analysis, predictors of surgical mortality and postoperative angina were identified retrospectively in 189 patients having had coronary arterial bypass surgery over the period 1978-1984. After modification of these risk factors, surgical outcome was followed up in another 178 patients undergoing operation from 1985 to 1987. The surgical mortality of 7% in the first series was closely associated with postoperative signs of acute myocardial injury. All deaths occurred in patients having at least 3 out of 5 pre- and peroperative risk factors: triple vessel/left main coronary arterial disease, incomplete revascularization, no propranolol treatment, Bretschneider cardioplegia other than "HTP"-solution with blood preperfusion and perioperative vasopressor support. The procedures of cardiac protection were modified. St Thomas multidose potassium cardioplegia and general hypothermia were introduced, perioperative propranolol treatment increased and bypass time decreased. Improved cardiac protection with this regime was seen in the patients operated in 1985-1987 when compared with the first series with regard to perioperative vasopressor support (8 vs 33%, P less than 0.001), spontaneous operative defibrillation (72 vs 52%, P less than 0.001), postoperative arrhythmias (20 vs 43%, P less than 0.001), peak levels of serum enzymes (P less than 0.001), myocardial infarction (7 vs 19%, P less than 0.001) and hospital mortality (2 vs 7%, P less than 0.05). The incidence of freedom from symptoms at 3 months was also increased in the patients undergoing operation from 1985 to 1987 (72 vs 61%, P less than 0.05). Even small centers can improve their surgical outcome by carefully analysing their own results and modifying the identified risk factors.

Angina Pectoris↗