Closing the loop: optimizing physicians' operational and strategic behavior.

Clinical databases are essential elements in optimizing medical care. They are no finality by themselves, but essential elements in the generation of knowledge. Optimal medical care starts with optimal care based on existing knowledge. This care continues with the registration of the variability in morbidity, comorbidity, and therapy, but also the registration of the early and late outcome. This should then allow the generation of structured inferences based on this registration and the closure of the loop, by treating patients according to this newly created evidence.

Does arterial revascularization decrease the risk of infarction after coronary artery bypass grafting?

BACKGROUND: This study sought to determine whether extensive arterial grafting reduces the prevalence and consequences of infarct after coronary artery bypass grafting. METHODS: Post-primary coronary artery bypass grafting infarcts and time-related events thereafter were identified by 99.9% complete follow-up of 9,600 patients (1971 to 1992). The contribution of arterial grafting to freedom from infarct was assessed by multivariable hazard function analysis to adjust for other risk factors. RESULTS: Unadjusted 1-month and 10-year freedom from infarction was 97% and 86%. By multivariable analysis, arterial grafting lowered the prevalence of periprocedural (p = 0.005), intermediate term (p = 0.007 and 0.006), and late infarction (arterial grafting to the left anterior descending coronary artery, p = 0.0006). Unadjusted survival after first infarct after coronary artery bypass grafting was 74% and 52% at 1 and 10 years; arterial grafting improved 10-year survival from 48% to 59% (p = 0.002). An additional benefit or cost of extending arterial grafting (n = 1,727) beyond a single one could not be identified (p > 0.1). CONCLUSIONS: Arterial conduits, particularly to the left anterior descending coronary artery, should be used for coronary artery bypass grafting to reduce early and late myocardial infarction and its consequences. However, use of more than a single arterial graft appears to confer no additional benefit.

Left ventricular assistance with the transthoracic 24F Hemopump for recovery of the failing heart.

BACKGROUND: The Hemopump was developed as a more powerful assist device for postcardiotomy support in patients in whom the intraaortic balloon pump is insufficient. METHODS: Over a 2-year period 21 (0.8%) of 2,585 patients undergoing cardiac operations needed a ventricular assist device because of postcardiotomy heart failure unresponsive to pharmacologic and intraaortic balloon support. Sixteen of these patients were assisted with the 24F transthoracic Hemopump left ventricular assist device. The aim of the mechanical support was myocardial recovery as the underlying conditions (age, arterial hypertension, diabetes, vascular and pulmonary disease) excluded heart transplantation. RESULTS: Hemodynamic improvement was apparent with a decrease in left atrial pressure (mean, 18.6 to 9.2 mm Hg), an increase in arterial blood pressure (mean, 54.1 to 70.1 mm Hg), and an increase in cardiac index. Five patients died within the first 24 hours because of low cardiac output. Although the heart was well unloaded (decrease in left atrial pressure of 8 +/- 4.69 mm Hg versus 9.3 +/- 5.51 mm Hg for the other patients), the increase in cardiac index was significantly lower (+0.516 versus +1.377 L.min-1.m-2; p = 0.027). Three of these 5 patients were known to have severe left ventricular hypertrophy. Of the remaining 11 patients, 2 were assisted for 1 week but failed to show recovery of the myocardium, 8 (50%) were weaned, and 4 (25%) were discharged. There were no device-related complications except the thrombosis of a cannula that was left for 10 days. CONCLUSIONS: The transthoracic Hemopump is an easy-to-use and reliable assist device. Left ventricular hypertrophy is a relative contraindication for the use of the Hemopump.

Determinants of early and late results of combined valve operations and coronary artery bypass grafting.

BACKGROUND: Factors determining the outcome of operative correction of valvular abnormalities combined with coronary artery bypass grafting are still incompletely defined. METHODS: Determinants of early and late (more than 90 days) deaths and event-free survival were studied for combined valve operations and coronary artery bypass grafting in 741 patients using multivariate analysis. RESULTS: Ninety-day survival probability was 89% (95% confidence interval, 87% to 92%). Preoperative risk factors for early death were age, female sex, renal failure, New York Heart Association class IV or V, and mitral insufficiency. The operative risk factor was the duration of aortic cross-clamping. Five- and 10-year survival probabilities were 74% (95% confidence interval, 71% to 78%) and 43% (95% confidence interval, 36% to 50%), respectively. Preoperative risk factors for late death were age, preoperative renal failure, New York Heart Association class IV or V, vessel disease, and nonsinus rhythm. Five- and 10-year event-free survival probabilities were 57% (95% confidence interval, 53% to 61%) and 23% (95% confidence interval, 17% to 28%), respectively. Preoperative risk factors for non-event-free survival were age, female sex, reduced left ventricular function, mitral regurgitation, and pacemaker rhythm. CONCLUSION: The demographic factors of age and female sex; the comorbid condition of renal failure; the cardiac conditions of advanced New York Heart Association class, left ventricular function, mitral regurgitation, vessel disease, and cardiac rhythm; and the operative condition of ischemia time are the most important predictors of clinical outcome after combined valve operations and coronary artery bypass grafting.

Left ventricular assist with an axial flow pump (Hemopump): clinical application.

Eighteen patients suffering from acute left heart failure were selected as candidates for Hemopump support. In 6 patients, peripheral atheromatosis prevented insertion of the device. Of the remaining 12 patients, 9 had postcardiotomy shock, 2 had acute rejection after orthotopic heart transplantation, and 1 had acute myocardial infarction complicated by a large postinfarction ventricular septal defect. During Hemopump support, hemodynamics recovered in all patients. Major complications were related to mechanical pump failure, such as fracture of the drive cable and expulsion of the cannula out of the ventricle, or to hemolysis of variable degree. Seven patients (58%) survived and were discharged from the hospital: the 2 patients bridged to heart transplantation and 5 of the 9 postcardiotomy patients, including 1 who could not be weaned but later underwent successful transplantation. The patient with the postinfarction ventricular septal defect died after removal of the device because of hemolysis. These results indicate that the Hemopump is a relatively noninvasive and efficacious left ventricular system of moderate power.

Aorto-enteric fistula as clinical entity.

A 19 year experience (1958-1977) with aortoenteric fistulas is presented. An aorto-enteric fistula is a direct communication between the aortic lumen and the gastro-intestinal tract producing a gastro-intestinal bleeding. The commonest cause of a primary or spontaneous aorto-enteric fistula is aneurysm formation. If there has been an operation on the aorta then the aorto-enteric fistula is called secondary. No primary aorto-enteric fistulas were encountered but thirteen secondary aorto-enteric fistulas are reported on a total of 841 aorto-femoral by-pass operations reviewed. Six hundred and sixty-one of these had an acceptable follow-up: this gives a 2% incidence. Our survival rate is 40%. Four different possible mechanisms are proposed for the formation of the secondary aorto-enteric fistula: anastomotic aneurysm formation, fibrous reaction, intra- or postoperative contamination or a combination of these possibilities. Some etiological factors as type of anastomosis, suture material, prosthesis material, hypertension, end-arterectomy and preoperative aneurysmatic tendency are analysed. A study is made of the different available diagnostic tools and the different possible therapies are discussed.

Anastomotic aneurysms of the femoral anastomosis after aortic bifurcation graft.

A 17 year experience (1958-1975 with anastomotic aneurysms of the femoral anastomosis after aortic bifurcation graft is presented. An anastomotic aneurysm is a progressive dilatation of an anastomosis between an artery and a prosthesis, caused either by a defective suture line or by a wall dilatation. One thousand one hundred and eighty-four femoral anastomoses with a decent follow-up were reviewed and 89 aneurysms were encountered, a per site incidence of 7.5%. Aetiological agents were arterial hypertension, non-infective bad wound healing, type of suture material, defect of the graft and trauma. The therapeutical approach with only 12% recurrences is a segmental interposition. The rate of satisfactory results was 78%. By reducing our bad wound healing from 15 to 10% of the anastomoses over the last five years, we reduced considerably our percentage of anastomotic aneurysms. The use of ultraleight weight prostheses seems to have also reduced the incidence and, in our study that we closed in December 1975, we encountered no aneurysm on Cooley or Milliknit, even with a follow-up of four years. Since the end of the study, however, we encountered one case of bilateral anastomotic aneurysm with Milliknit, one year after the primary operation but with a definite trauma in the anamnesis.

Carotid endarterectomy for cerebrovascular insufficiency. Long term follow-up of 141 patients followed up to sixteen years.

Between 1962 and 1978 one hundred and fifty-nine endarterectomies were performed on 141 patients. The operation was done under general anesthesia with the use of a shunt and hypertension as cerebral protection. The arteriotomy was closed using a dacron patch. The postoperative evolution of every neurological symptom was analysed after a follow-up of up to sixteen years. The patients were divided in three groups following their neurological and anatomical situation. On 43 totally asymptomatic patients (group I), there was one perioperative death, 41 remained totally asymptomatic and one developed a transient ischemic attack on the non operative side. On 25 patients (group II) operated after symptomatic contralateral total occlusion, fifteen became asymptomatic, six improved seriously, one remained unchanged, and one suffered from a stroke with complete recuperation. Two perioperative deaths were encountered in this group. On the 73 patients from group III, there were three perioperative deaths. Fifty-two patients became totally asymptomatic, nine patients had a serious amelioration of their residu. Three remained unchanged. Five patients suffered from a long term deterioration of their neurological condition and one patient developed an anastomotic aneurysm.