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J J Defauw

Publications and source records attributed to J J Defauw.

At least 37 records · Page 2Linked to original sources
PubMed1994

Risk assessment of acute renal failure after thoracoabdominal aortic aneurysm surgery.

OBJECTIVE: The authors sought a statistical model that permits the calculation of the chance of postoperative dialysis in patients undergoing thoracoabdominal aortic aneurysm repair. The preoperative risk of each individual patient was assessed. SUMMARY BACKGROUND DATA: Acute renal failure requiring dialysis after thoracoabdominal aortic aneurysm surgery is a common complication. Despite modern intensive care facilities, it continues to be associated with high morbidity and mortality. METHODS: The authors studied the influence of preoperative and intraoperative variables thought to be important clinically in the development of serious acute renal failure in 88 consecutive patients. Simple cross-clamping was used with the Crawford's graft inclusion technique without shunts or heparin. Statistical methods used include univariate and multivariate analysis (stepwise logistic regression analysis and Cox proportional hazard model). RESULTS: The hospital mortality was 11.4% (n = 10). Long-term survival at 2 years was 78% (+/- 4.4), and at 5 years was 54% (+/- 5.3). A logistic regression model with only two explanatory variables to predict postoperative dialysis showed an almost perfect fit (chi 2 = 4.2, p = 0.84): the risk factors of postoperative dialysis were age (p = 0.003) and the preoperative serum creatinine level (p = 0.04). As determined by stepwise Cox regression analysis, postoperative dialysis also was a significant risk factor for late death (p = 0.002). CONCLUSIONS: Using this statistical model, the chances of postoperative dialysis can be estimated exactly before operation; age and preoperative serum creatinine level are the only variables predictive for postoperative dialysis.

Acute Kidney Injury↗
PubMed1994

Long-term results of the corridor operation for atrial fibrillation.

OBJECTIVE: To investigate the long-term results of the corridor operation in the treatment of symptomatic atrial fibrillation refractory to drug treatment. BACKGROUND: The corridor operation is designed to isolate from the left and right atrium a conduit of atrial tissue connecting the sinus node area with the atrioventricular node region in order to preserve physiological ventricular drive. The excluded atria can fibrillate without affecting the ventricular rhythm. This surgical method offers an alternative treatment when atrial fibrillation becomes refractory to drug treatment. PATIENTS: From 1987 to 1993, 36 patients with drug refractory symptomatic paroxysmal atrial fibrillation underwent surgery. The in hospital rhythm was followed thereafter by continuous rhythm monitoring and with epicardial electrograms. After discharge Holter recording and stress testing were regularly carried out to evaluate the sinus node function and to detect arrhythmias; whereas Doppler echocardiography was used to measure atrial contraction and size. MAIN OUTCOME MEASURES: Maintained absence of atrial fibrillation without drug treatment after operation; preservation of normal chronotropic response in the sinus node. RESULTS: The corridor procedure was successful in 31 (86%) of the 36 patients. After a mean (SD) follow up of 41 (16) months 25 (69%) of the 36 patients were free of arrhythmias without taking drugs (mean (SE) actuarial freedom at four years 72 (9)%)). Paroxysmal atrial fibrillation recurred in three patients; paroxysmal atrial flutter (two patients) and atrial tachycardia (one patient) developed in the corridor in three others. Among the 31 patients in whom the operation was successful sinus node function at rest and during exercise remained undisturbed in 26 and 25 patients respectively (mean (SE) actuarial freedom of sinus node dysfunction at four years (81(7)%)). Pacemakers were needed in five (16%) of the 31 patients for insufficient sinus node rhythm at rest only. Doppler echocardiography showed maintenance of right atrial contribution to right ventricle filling in 26 of the 31 patients after operation in contrast to the left atrium, which never showed such contribution. His bundle ablation was performed and a pacemaker implanted in the five patients in whom the corridor operation was unsuccessful. CONCLUSION: These results substantiate the idea of this surgical procedure. Modification of the technique is, however, needed to achieve a reliable isolation between left atrium and corridor, which would make this experimental surgery widely applicable in the treatment of drug refractory atrial fibrillation.

Atrial Fibrillation↗
PubMed1994

Surgical treatment of thoracoabdominal aortic aneurysms by simple crossclamping. Risk factors and late results.

Between 1981 and 1987, 88 consecutive patients were operated on for a thoracoabdominal aortic aneurysm by simple crossclamping and a graft inclusion technique (without shunts or heparin). This article presents an analysis of the operative outcome and long-term follow-up. Patient- and operation-related variables are age (mean 64.3 years, range 28 to 82 years), sex (82% men), rupture (20.5%), diabetes (2.3%), renal insufficiency (34.1%), chronic obstructive pulmonary disease (27.3%), previous aortic operation (31.8%), arterial hypertension (66%), postdissection (18.2%) versus degenerative (80.7%) origin, preoperative shock (11.4%), ischemic cerebrovascular (12.5%) or ischemic heart (17%) disease, peripheral vascular disease (14.8%), renal (mean 48 minutes, range 0 to 83 minutes) and lower spinal cord (mean 21 minutes, range 0 to 68 minutes) ischemic time, number of reattached intercostals, blood loss, and extent of the aneurysm (Crawford classification: type I, 16 patients [18.2%]; type II, 21 patients [23.8%]; type III, 29 patients [33%]; and type IV, 22 patients [25%]. Intraoperative mortality is 1.1% (n = 1). Thirty-day mortality is 5.9% (n = 5). Hospital mortality is 11.4% (n = 10): 7% for elective cases and 28% for ruptured aneurysms (p = 0.014). The survival at 2 years is 78% +/- (4.4%) and at 5 years 54% +/- (5.3%). Postoperative spinal cord injury occurred in 12 patients (13.8%) (5 had paraplegia and 7 had paraparesis) and postoperative renal dysfunction necessitating dialysis in 12 patients (14.1%). Risk stratification for hospital death, late death, renal failure, and spinal cord dysfunction was performed by means of multivariate logistic regression and Cox proportional hazard regression as appropriate. The best fitting model to predict hospital death includes preoperative shock (p = 0.02), female sex (p = 0.06), preoperative elevated serum creatinine level (p = 0.06), and preoperative myocardial infarction (p = 0.08). Variables predictive for late death are postoperative dialysis (p = 0.002), age (p = 0.008), and rupture (p = 0.04). The risk factors of postoperative dialysis are age (p = 0.003) and preoperative serum creatinine level (p = 0.04). The risk of postoperative spinal cord dysfunction increases with longer lower spinal cord ischemic time (p = 0.02) and with the presence of preoperative shock (p = 0.06).

Adult↗
PubMed1993

Age thresholds for prophylactic replacement of Björk-Shiley convexo-concave heart valves. A clinical and economic evaluation.

BACKGROUND: Björk-Shiley convexo-concave heart valves have an increased risk of mechanical failure. One might consider prophylactic rereplacement as a preventive measure to avert the disastrous consequences of these failures. We investigated the effect that prophylactic rereplacement has on survival of individual patients and on the medical costs. METHODS AND RESULTS: Quantitative estimates for the surgical risks of prophylactic replacement of Björk-Shiley valves, long-term survival, and the risk of outlet strut fracture were derived insofar as possible from a detailed analysis of a follow-up study conducted in The Netherlands, including 2303 patients with a mean follow-up of 6.6 years. On the basis of these estimates, we calculated life expectancy with and without prophylactic replacement. For the various valve types, age thresholds were determined below which rereplacement prolongs (discounted quality-adjusted) life expectancy. We also calculated the cost per year of life gained as a function of age. The age thresholds below which prophylactic rereplacement increases life expectancy (expressed in simple future years of life) for male patients without comorbidity, if the surgical mortality after rereplacement is equivalent to that of primary replacement, are 27, 48, 51, and 65 years for small and large 60 degrees and for small and large 70 degrees mitral valves, respectively. For aortic valves, these age thresholds lie somewhat higher: 39, 52, 56, and 76 years, respectively. Repeat analyses indicated that for women, all age thresholds lie about 1 or 2 years higher. These age thresholds decrease considerably if the surgical mortality after rereplacement is considered to be higher after prophylactic rereplacement than after primary replacement or if comorbidity is present. The costs per discounted and quality-adjusted year of life gained depend on type and position of the Björk-Shiley convexo-concave heart valve and rise steeply as the patient's age approaches the threshold for rereplacement. CONCLUSIONS: The results of the Dutch follow-up study allow guidance for prophylactic replacement of the Björk-Shiley convexo-concave valve on an individual basis. Rereplacement compares favorably with expectant management in some patient subgroups with both 60 degrees and 70 degrees valves. Age thresholds may serve as a first step in identifying patients in whom rereplacement might be beneficial.

Adult↗
PubMed1992

Initial and long-term results of percutaneous transluminal coronary angioplasty in patients 75 years of age and older.

In 212 patients aged 75 years and older the immediate and long-term results of percutaneous transluminal coronary angioplasty (PTCA) were assessed. For 293 stenoses the primary angiographic success rate was 96% and the overall clinical success rate was 90.6%. Angioplasty caused a myocardial infraction in 7 patients (3.3%), 2 patients (0.9%) needed emergency aorto coronary bypass surgery, and 4 patients (1.9%) died following the procedure. Actuarial 7 year survival was calculated at 69.3% with a standard deviation (SD) of 8%. Actuarial cardiac survival at 7 years was 92.1% (SD 3%), whereas non-cardiac survival at 7 years was 75.3% (SD 9%). Actuarially, at 7 years 98.5% (SD 1%) were estimated to remain free from myocardial infarction in the angioplasty-related area, 95.7% (SD 2%) to remain free from any myocardial infarction, 93.9% (SD 2%) to remain free from re-PTCA because of a recurrence, 84.7% (SD 5%) to remain free from any re-PTCA, and 97.1% (SD 2%) to remain free from (re)-operation. Fifty-two point three percent (SD 8%) were estimated to remain free from any cardiac event. If recurrence of angina is taken into account, only 25.8% (SD 13%) remain asymptomatic during 7 years follow-up. After successful angioplasty in patients aged 75 and older the chance of remaining free from any event or angina at 7 years actuarial follow-up gets as low as 15.7% (SD 9%). We conclude that in selected elderly patients angioplasty can be performed with a high success rate, although the periprocedural mortality and morbidity appear to be higher than in the younger age group. During long-term follow-up, most of the patients remain free of cardiac events and survival appears to be largely dependent on noncardiac factors. However, long-term relief from angina is probably less than in younger patients.

Actuarial Analysis↗
PubMed1992

Synchronous operation for ischemic cardiac and cerebrovascular disease: early results and long-term follow-up.

The late follow-up of 230 patients who underwent synchronous operation for extensive, obstructive extracranial and coronary artery disease from 1974 to 1989 was analyzed. Mean age at operation was 62.5 years; 161 patients (70%) were in New York Heart Association class III or IV, 185 (80%) had triple-vessel disease, and 67 (29%) had left main stem lesions of 50% or more. Previous myocardial infarctions were present in 132 patients (57%). Only 78 had normal left ventricular function. Included were 16 patients undergoing coronary reoperations, 17 patients with additional cardiac procedures, and 3 with synchronous pulmonary procedures. Symptomatic extracranial vascular disease or stabilized neurological deficits were present in 108 patients. Bilateral hemodynamically significant carotid disease was present in 91 patients and arch vessel lesions in 37. The hospital mortality in 8 patients (3.5%) was due to cardiac (n = 4), neurological (n = 1), or multiorgan failure (n = 3). Operative morbidity was mainly neurological (n = 20, 8.7%): 7 reversible deficits and 7 major strokes occurred, 2 reversible and 5 major strokes were related to the operated side(s), and 4 postoperative myocardial infarctions occurred. Actuarial survival at 5 years was 74% (+/- 3.3), at 10 years 54% (+/- 4.9), and at 15 years, 35% (+/- 6.6). This was mainly determined by late cardiac death (41/66). Late morbidity was mainly attributable to cardiac causes rather than neurological causes. At 5 and 10 years, respectively, 72% and 44% of the patients were free of major cardiac and neurological events or death. Synchronous revascularization can be performed relatively safely. The long-term outcome is determined by the extent and severity of the cardiovascular disease.

Adult↗
PubMed1992

Surgical therapy of paroxysmal atrial fibrillation with the "corridor" operation.

Patients with paroxysmal atrial fibrillation may be extremely disabled despite medical therapy. Based on recent concepts of atrial fibrillation, a surgical open heart procedure was designed to isolate a "corridor" from the right and the left atrium. The corridor consists of the sinus node area, the atrioventricular nodal junction, and the connecting right atrial mass, small enough to prevent atrial fibrillation. Between 1987 and 1990, 20 patients with severely disabling symptoms due to frequent paroxysmal atrial fibrillation underwent the corridor operation, with permanent success in 16 patients. In 8 patients, left atrium to corridor conduction reappeared shortly after the procedure. Reoperation was performed in these patients without extracorporeal circulation. The site of persistent conduction between the left atrium and the corridor could consistently be localized adjacent to the coronary sinus. Nevertheless, reoperation failed to isolate permanently the corridor in 4 patients. During a mean follow-up of 20 months, atrial fibrillation dominating the ventricles was never observed nor inducible in the corridor in the 16 patients with a successful operation. In all cured patients, sinus node function remained undisturbed. Paroxysmal atrial flutter inside the corridor arose in 1 patient and a paroxysmal focal tachycardia in another. All 16 cured patients experienced a clear improvement in quality of life. Refinement of the surgical technique to obtain persistent isolation between the left atrium and the corridor is needed. These results demonstrate that the concept of the corridor operation is sound and justify its use in the treatment of drug-refractory paroxysmal atrial fibrillation.

Adult↗
PubMed1992

Completion pneumonectomy after bronchial sleeve resection: incidence, indications, and results.

During the years 1960 through 1989, 145 patients underwent sleeve lobectomy or sleeve resection of a main bronchus. Completion pneumonectomy was performed in 19 patients (13.1%). Indications were bronchostenosis without malignancy in 10 patients, positive resection margins in 3, recurrent tumor in 5, and anastomotic dehiscence in 1. Mean age at sleeve operation was 59.3 years. In 18 patients the histology was squamous cell carcinoma and in 1 patient, carcinoid tumor. The mean interval between sleeve resection and completion pneumonectomy was 5.7 months (range, 3 to 16 months) for the patients with stenosis and 6.6 months (range, 1 to 17 months) for the others. There were 3 operative deaths (15.8%). The mean follow-up was 53.2 months. Five-year and 10-year survival rates after completion pneumonectomy for the patients with stenosis were 54% and 41%, respectively, and for the others, 52% and 52%.

Adult↗
PubMed1992

Increased dispersion of "refractoriness" in patients with idiopathic paroxysmal atrial fibrillation.

The average interval between local depolarizations during atrial fibrillation, the so-called atrial fibrillation interval, was used as an index for local "refractoriness." This was based on the assumption that during fibrillation, cells are reexcited as soon as their refractory period ends. A very good correlation was found between refractory periods determined with the extrastimulus technique at a basic cycle length of 400 ms and atrial fibrillation intervals measured at the same epicardial sites of the right atrium. This new technique was used to assess dispersion in atrial fibrillation intervals in 10 patients with idiopathic paroxysmal atrial fibrillation and in a control group of 6 patients who were undergoing cardiac surgery. After a routine median sternotomy a multiterminal grid with up to 40 electrodes was placed over the right atrium, and atrial fibrillation was induced by premature stimulation. The average fibrillation interval in the test group, recorded at 247 sites, was 152 +/- 3 ms and that in the control group, recorded at 118 sites, was 176 +/- 8.1 ms (p less than 0.05). Dispersion in atrial fibrillation intervals, defined as the variance of the fibrillation intervals at all the recording sites, was three times larger in the group with paroxysmal atrial fibrillation than in the control group. This study suggests that both a shorter refractory period and a larger dispersion in refractoriness are responsible for the recurrence of atrial fibrillation.

Atrial Fibrillation↗
PubMed1992

Endocarditis on a left atrial myxoma.

A 55-year-old woman presented with fever and malaise. Three blood cultures were positive for Streptococcus sanguis. A diagnosis of endocarditis was made and the patient was treated with intravenous penicillin and gentamicin. Endocardiography revealed a large left atrial tumour. At operation a myxoma covered by deposits of fibrin was excised. Microscopy revealed massive infiltrates of neutrophils and remnants of bacteria, indicating that this myxoma was a nest for infection.

Endocarditis, Bacterial↗
PubMed1992

Second primary lung cancer after bronchial sleeve resection. Treatment and results in eleven patients.

During the years 1960 to 1989, 145 patients underwent sleeve lobectomy or sleeve resection of a main bronchus. Follow-up was complete except for one patient, who was no longer available for follow-up 4 years after operation. Eleven patients (7.6%) had a second primary cancer in the lung; 10 of these patients (90.9%) were men. Mean age at sleeve operation was 61.2 +/- 11.6 years. Mean interval between sleeve operation and development of second primary cancer was 53.8 months (range, 6 to 197 months). All second primary cancers occurred on the contralateral side. In five cases there was squamous cell carcinoma, in two there was adenocarcinoma, in one there was adenosquamous carcinoma, in two there was small cell carcinoma, and in one patient no definite histologic type could be established. Five patients had different histologic type from the initial, resected primary tumor. Seven patients (64%) were operated on: five underwent lobectomy and two underwent segmentectomy. In one patient the tumor was judged to be unresectable. Chemotherapy was given to the two patients with small cell carcinoma and radiotherapy was given to one patient with bone metastases. Follow-up was complete for these 11 patients. Data were calculated from detection of second primary cancer. There was one postoperative death from myocardial infarction. Eight other patients died during follow-up: five died of recurrent tumor or metastases, two died of acute cardiac failure, and one died of a perforated ulcer. The 1- and 4-year actuarial survivals were 41% and 30%, respectively. For the patients operated on, 1- and 4-year survivals were 57% and 43%, respectively. There were no survivors at 5 years. Sleeve resection is a valuable method of preserving functional lung tissue. It offers a chance of subsequent resection in patients who have second primary cancer, with acceptable results.

Actuarial Analysis↗
PubMed1991

TNM staging and long-term follow-up after sleeve resection for bronchogenic tumors.

From 1960 to 1989, 145 patients (132 men and 13 women) with a mean age of 60.3 years underwent sleeve lobectomy or sleeve resection of a main bronchus for a bronchogenic tumor. Squamous cell carcinoma was predominantly found (116 patients, 80.0%), followed by carcinoid tumor in 13 patients (9.0%). Postoperative staging was: stage I, 61 patients (42.1%); stage II, 47 (32.4%); stage IIIA, 33 (22.8%); and stage IIIB, 4 (2.7%). Thirty-day mortality was 4.8% (7 patients). Follow-up was complete except for 1 patient who was lost to follow-up 4 years after operation. For the whole group, 5-, 10-, and 15-year survival rates were 49%, 37%, and 18%, respectively. Better survival was noted in patients with carcinoid tumor and squamous cell carcinoma. Considering 112 patients with T2 and T3 squamous cell carcinoma, 5- and 10-year survival rates for N0 disease (52 patients) were 59% and 47%, for N1 disease (51 patients) 21% and 0%, and for N2 disease (9 patients) 44% and 0%. Differences between N1 and N2 disease were not statistically significant. Survival after sleeve resection is best for carcinoid tumors and squamous cell carcinoma with negative nodes. Presence of N1 or N2 disease significantly worsens prognosis, with no 10-year survivors and no difference between N1 and N2 status.

Carcinoma, Bronchogenic↗
PubMed1991

Macroreentry in the infarcted human heart: the mechanism of ventricular tachycardias with a "focal" activation pattern.

Endocardial mapping of electrical activity was carried out in 150 patients to guide antiarrhythmic surgery for drug-resistant ventricular tachycardia in the chronic phase of myocardial infarction. In 20 of these patients, the activation pattern of 27 distinct tachycardias was focal and diastolic potentials were recorded at three or more sites. In 26 tachycardias, the sequence of diastolic potentials progressed from the area of latest activation of one cycle toward the "origin" of the next cycle. In two patients, the heart was stimulated during tachycardia, resulting in entrainment of the tachycardia in both. Late potentials were recorded during entrainment at sites where diastolic potentials occurred during tachycardia. In 11 of the 20 patients, endocardial mapping was performed during sinus rhythm. In four of these, late potentials were observed during sinus rhythm at sites where diastolic potentials were recorded during tachycardia. In two patients without late potentials during sinus rhythm, late potentials were observed during stimulation and induced ectopic beats. The results support the concept that the mechanism of several of these tachycardias is based on reentry in a macrocircuit comprising a tract of surviving tissue traversing the infarct and the remaining healthy tissue. They also indicate that the absence of late potentials during sinus rhythm does not guarantee the absence of arrhythmogenic pathways.

Cardiac Catheterization↗
PubMed1990

[10-year experience with the surgical treatment of ventricular tachycardia following acute myocardial infarction].

From 1980 to 1988 direct arrhythmia surgery was performed in 121 patients suffering from postinfarction drug-refractory ventricular tachycardia (VT). By 1986 the initially high in-hospital mortality of 26% (18 of 69 patients) had decreased to 1.9% (1 of 52 patients). The 3-year actuarial survival of patients operated since 1986 is 90%. From 1985 the results of surgical therapy of VT have improved: 86% of the patients remained arrhythmia-free without drugs; none died suddenly. Residual left ventricular function was related to the prognosis, but the interval between the last myocardial infarction and time of surgery or the surgical technique were not. These results demonstrate that direct surgery has become a valuable method in the treatment of postinfarction VT, at least in patients with sufficient residual left ventricular function.

Adult↗
PubMed1989

[The surgical treatment of aneurysms of the descending thoracic aorta].

Between June 1983 and December 1987, 52 patients underwent resection of a thoracic descending aortic aneurysm. Thirty-day mortality was 11.5%; 4.8% for elective cases and 36.5% for patients operated upon in emergency. Spinal cord injury was present in two patients (4%). One patient was paraplegic, the other showed mild paraparesis, which was completely resolved. Both patients were operated for ruptured aneurysms. Severe postoperative renal dysfunction was present in 4 patients (7.5%) and was strongly related to intraoperative hypotension. The cumulative proportional survival rate was 81% at one year and 66% at two years of the total group, 85% at one year and 72% at two years for the patients presenting with nonruptured aneurysms. Aneurysms of the thoracic descending aorta can be resected with an acceptable mortality and morbidity. Just as in abdominal aneurysms, surgery definitely improves the outcome for these patients, who have a rather poor prognosis if left untreated.

Acute Kidney Injury↗