Prediction of surgical outcome after aortic valve replacement.

BACKGROUND: Aortic valve replacement has some major adverse outcomes. For these, the predictors need identification. METHODS: This was a retrospective file study of 1000 consecutive patients who underwent AVR for degenerative aortic valve disease. Twenty-five preoperative and 5 peroperative factors were screened by a univariate Fisher-exact analysis. The predictors were identified in a second step by logistic regression multivariate analysis. RESULTS: Five hundred thirty patients were male. The mean age was 75 (71-77) years and 610 also underwent CABG. For hospital mortality, need for urgent aortic valve replacement (p < 0.001) was the dominant predictor. Need for digitalis (p = 0.002) and age > 80 (p = 0.005) followed. For postoperative congestive heart failure, need for urgent aortic valve replacement was also dominant (p <0.001). Atrial fibrillation (p = 0.001,) and ejection fraction < 50% (p = 0.055) were less important. For ventricular arrhythmia, previous infarction (p = 0.025) and ejection fraction < 50% (p = 0.032) were identified. For bleeding, concomitant CABG (p = 0.046) and chronic obstructive pulmonary disease were identified. For thromboembolic events only an ejection fraction < 50% (p = 0.027) was identified. CONCLUSIONS: Need for urgent aortic valve replacement is the dominant predictor for postoperative mortality and congestive heart failure. Once a degenerative aortic valve disease becomes symptomatic, prompt referral could prevent the development for need for urgent surgery, with all its adverse postoperative consequences.

A thousand pericardial valves in aortic position: risk factors for postoperative acute renal function impairment in elderly.

AIM: Postoperative renal dysfunction after aortic valve replacement is a serious complication. To minimize its occurrence, risk factors have to be identified, and if possible eliminated. METHODS: Of 1000 consecutive patients, who underwent AVR, a file study was performed chi(2)nd logistic regression analysis were performed to study the effect of 24 preoperative, 7 peroperative and 7 postoperative factors on the occurrence of 30-day postoperative worsening of renal function. RESULTS: Fifty-three patients had a 30-day postoperative decrease of renal function. Nine of these patients died, which is significantly more than the mortality without this complication (P<0.0001). In those nine patients, another complication (postoperative heart failure, thromboembolism or respiratory failure) was present. Thirteen factors were significant in an univariate analysis: preoperative renal dysfunction (P<0.001), age>80 (P<0.001), atrial fibrillation (P<0.001) , preoperative pulmonary edema (P=0.001), conduction defect (P=0.002), diabetes (P=0.006), myocardial infarction (P=0.006), postoperative heart failure (P=0.007), cross clamp time >75 min (P=0.015), previous coronary artery bypass grafting (CABG) (P=0.018), concomitant CABG (P=0.031), ejection fraction <50% (P=0.033) and CVA (P=0.035). Four factors were identified as independent predictors in a multivariate analysis: renal dysfunction (P<0.001, Odds ratio [OR] 5.5; 95% confidence interval [CI] 2.9-10.4), preoperative atrial fibrillation (P=0.010, OR=2.3, 95% CI=1.2-4.2), age>80 (P=0.014, OR=2.2, 95% CI=1.2-4.1) and myocardial infarction (P=0.022, OR=2.2, 95% CI=1.1-4.4). CONCLUSIONS: Few factors are liable for therapeutic intervention, especially in elderly and patients with comorbidity. In patients with risk factors, shortening of cross clamping time or installation of minimal extracorporeal circulation might be beneficial.

Timing of aortic valve replacement in elderly patients with symptomatic aortic valve disease using outpatient clinical parameters.

OBJECTIVE: To determine by how far worsening outpatient clinical parameters can affect outcome after aortic valve replacement, in patients with preserved left ventricular function and symptomatic aortic valve disease. PATIENTS AND METHODS: Five hundred patients with aortic valve disease underwent aortic valve replacement using a bioprosthesis. In 348 patients, another procedure was added. The preoperative outpatient parameters were investigated for their effect on hospital and long-term mortality. A Fisher exact, Kaplan-Meier univariate and Cox proportional hazard analysis were used. RESULTS: A retrospective follow-up of 2022 patient years was obtained. Five preoperative parameters were found to be more present in patients with a decreased left ventricular function: 1) severity of symptoms, 2) previous myocardial infarction, 3) conduction defects, 4) aortic valve regurgitation and 5) increasing need for medication. In patients with an ejection fraction of 50% or more, logistic regression analysis showed that hospital mortality increased with need for medication (p=0.004), previously performed CABG (0.015), increase in symptoms (p=0.018) and myocardial infarction (p=0.034). A Kaplan-Meier analysis revealed aortic valve regurgitation (p=0.017) and increased need for medication (p=0.012) as significant on long-term survival. Presence of a previous myocardial infarction showed a trend (p=0.062). A Cox' proportional hazard analysis showed for global mortality increased need for medication (p=0.010) and previous myocardial infarction (p=0.018) as independent factors and for long-term mortality, this was aortic valve regurgitation (p=0.001). CONCLUSIONS: Results after aortic valve replacement deteriorate with the presence of valve regurgitation, a preoperative myocardial infarction, increasing need for medication or severity of symptoms, even for an ejection fraction of 50% or more. Anamnesis with special care to the degree of symptoms and increasing need for medication early in the valve disease could lead to early referral, thereby reducing number of patients with severe symptoms and improving postoperative results.

Current status of proximal gastric vagotomy, one hundred years after Pavlov: is it finally history?

One hundred years ago, the role of the vagal nerve in gastric acid production was established. After the second World War, this paradigm served as the basis of treatment of peptic ulcer disease by pharmacological or surgical means. A remarkable parallelism between the developments of both approaches was observed in the 1970s. On the one hand, medication with less side effects became available. On the other hand, vagotomies were becoming more physiologic in nature and produced less postoperative symptoms. The elusive nature of peptic ulcer disease and the inability to cure this by medication were acknowledged. Very few investigators, however, had reported on a possible infectious origin of peptic ulcer disease and those reports were old. After 1984, the role of Helicobacter pylori in the disease was discovered. With this shift in paradigm, the treatment of peptic ulcer disease changed radically, despite attempts in the surgical community to develop simplified operations. This illustrates that neither the most powerful acid reducing drugs on their own, nor the most physiological and least invasive surgical techniques stand the test of time if the underlying paradigm changes. It also illustrates that old ideas should not be overlooked.

Thromboembolic events after aortic valve replacement in elderly patients with a Carpentier-Edwards Perimount pericardial bioprosthesis.

OBJECTIVES: Thromboembolic events after aortic valve replacement with a bioprosthesis were the most frequently occurring complications in elderly patients. Whether this was valve related or dependent on other factors needed further exploration. METHODS: Five hundred patients with a median age of 73 years were followed retrospectively after aortic valve replacement with a pericardial prosthesis for occurrence of thromboembolism. Of these, 348 also underwent coronary artery bypass grafting. Twenty-five factors were investigated for their potential effect by using univariate and multivariate analysis. RESULTS: Univariate analysis revealed 6 significant factors: preoperative endocarditis (P =.0001), preoperative cerebrovascular accident (P =.002), use of postoperative warfarin sodium (Coumadin, DuPont Merck; P =.006), arterial hypertension (P =.023), size of valve prosthesis of 27 mm or larger (P =.023), and hospital thromboembolism (P =.040). There was a trend toward increased fatal thromboembolism in patients without medication. With a multivariate analysis, 4 factors remained significant: preoperative cerebrovascular accident (risk ratio, 4.8; P =.0016), warfarin sodium (risk ratio, 3.0; P =.0028), preoperative endocarditis (risk ratio, 5.6; P =.006), and hospital thromboembolism (risk ratio, 6.1; P =.016). Hypertension had a borderline effect. Age, sex, diabetes, 4 coronary artery factors, 3 other valvular factors, atrial fibrillation, and carotid artery disease had no significant effect. CONCLUSIONS: Some emboli seemed triggered by the valve prosthesis. A proper anticoagulant protocol but also a treatment of hypertension is important in the prevention of thromboembolism after aortic valve replacement with a bioprosthesis. We did not find a significant role of atrial fibrillation and carotid artery disease.

Role of age, gender and association of CABG on long-term results after aortic valve replacement with a Carpentier-Edwards bioprosthesis in the elderly.

AIM: The problem of postoperative sudden death and the effect of age, gender and association of coronary artery bypass grafting were studied after implantation of a bioprosthetic valve in aortic position. DESIGN: retrospective investigation during 13 year. SETTING: general hospital. PATIENTS: 500 mostly symptomatic patients who received this bioprosthesis had a follow-up of 2,022 patient-year for 499 patients. INTERVENTION: aortic valve replacement with a Carpentier-Edwards pericardial prosthesis. MEASURES: hospital complications and mortality, long-term mortality with focus on sudden death and its risk factors, valve related complications and other cardiac events. RESULTS: Within the hospital: atrial fibrillation was the most frequent complication, for which only gender had an effect (p=0.014). The most occurring valve related complications were thrombo-embolic events. Mortality was adversely affected by male gender (p=0.040). Long-term results: thrombo-embolic events were the most important valve related complications. These events and haemorrhage, endocarditis and reoperation rate were not affected by the association of a CABG. Univariate analysis in patients over 73 showed that the need for CABG significantly increased global mortality (p=0.0001), occurrence of cardiac fatality (p=0.0003) and congestive heart failure (p=0.0036). Non-valve related factors seemed most responsible for postoperative sudden death. CONCLUSION: Age, male gender and the association of a CABG remain important determinants for postoperative survival, but not for the occurrence of valve related complications. Sudden death seems not always related to the valve prosthesis, but is as such classified by convention.

The effect of stress on gastric emptying rate measured with a radionuclide tracer.

BACKGROUND/AIMS: Stress can delay gastric emptying rate. This phenomenon has not yet been investigated with a physiological solid test meal or a regional analysis. METHODOLOGY: We investigated the gastric emptying rate in beagle dogs using a radio-labeled solid test meal and a gamma camera. The transport to an unknown environment served as a stress stimulus. This offers the advantage to mimic fairly well the clinical situation just before a diagnostic or therapeutic procedure. Control values were obtained after the third investigation, in which all dogs were accustomed to the environment. RESULTS: Regional analysis of the emptying curves from the whole gastric region revealed that the length of the lag phase increased with stress, but the post-initial emptying rate remained unchanged. Emptying of the fundus changed hardly, but the antropyloral motor activity decreased during stress. CONCLUSIONS: Gastric emptying rate is impeded during stress. It is necessary to limit the unnatural stress-stimuli, in order to mimic the clinical situation. Measurement techniques that influence directly gastric emptying or act as a stress-stimulus by themselves are undesirable. A radionuclide solid test meal is preferable and a regional analysis reveals the impairment of the antral motility as the mechanism of the delay of gastric emptying.

Determinants of survival after aortic valve replacement as treatment for symptomatic aortic valve disease in the elderly.

BACKGROUND AND AIM OF THE STUDY: The effect of concurrent disease and cardiac comorbidity on survival after bioprosthetic valve replacement in elderly patients was assessed retrospectively. Risk factors were categorized as general, non-cardiac (age, diabetes, previously treated carcinoma) and cardiac (LVEF, three-vessel disease, previous CABG or valve replacement, and endocarditis). METHODS: A total of 400 elderly patients (median age 73 years; range: 71-76 years) was studied. Medical history included diabetes, previous CABG or aortic valve replacement (AVR), endocarditis and treatment of previous carcinoma. A left ventricular ejection fraction (LVEF) of <0.66 and presence of three-vessel disease were also investigated. Hospital deaths (and cause) were recorded; survival or date and cause of death after discharge were obtained by questionnaire. Kaplan-Meier univariate and Cox proportional hazards multivariate regression analyses were carried out. RESULTS: Mortality during follow up was 28.3%; hospital mortality was 3.8%. Univariate analysis showed five factors significantly to affect survival: LVEF, history of endocarditis, carcinoma, age and three-vessel disease. Fifteen of 38 patients with history of carcinoma died, 10 due to a malignancy. Of 76 patients with three-vessel disease, 26 died. A history of diabetes and previous CABG did not influence survival significantly. Four of eight patients with preoperative endocarditis died, all in hospital. Six of 11 patients died after redo-AVR, none before 36 months follow up. By Cox regression analysis, LVEF and histories of carcinoma and endocarditis remained significant. CONCLUSION: AVR should be performed before ventricular deterioration occurs. Previous CABG is not a contraindication for AVR. Endocarditis impaired survival. Long-term mortality after redo-AVR in this population was relatively high, but acceptable. AVR should also be performed in elderly patients with aortic valve disease. Since prognosis of symptomatic aortic valve disease is poor in the short term, AVR is indicated in patients treated for carcinoma.

Gastric emptying rate for solid and for liquid test meals in patients with dyspeptic symptoms after partial gastrectomy and after vagotomy followed by partial gastrectomy.

BACKGROUND/AIMS: Gastric emptying rate for solid and for liquid test meals was investigated retrospectively in patients with longstanding epigastric distress after partial gastrectomy, either as primary treatment or after failure of vagotomy for peptic ulcer in order to find an explanation for the postoperative symptoms. METHODOLOGY: Radionuclide-labeled liquid and solid test meals were used to evaluate gastric emptying rate, at least one year after surgery. RESULTS: The lag phase for liquid test meals disappeared in all operated patients. Partial gastrectomy usually lead to fast emptying but this resective procedure, if performed after vagotomy, lead to stasis in a significant number of patients. Gastric emptying rate for solids increased in only a few of these symptomatic patients. In most of them however, there was a normal to decreased emptying rate. If a vagotomy had preceded the resective procedure, gastric emptying rate decreased significantly. CONCLUSIONS: In all these symptomatic patients, gastric emptying had been disturbed for at least one type of test meal. This makes investigation for both meals necessary, especially since there is a lack of correlation. Furthermore, if vagotomy fails to prevent ulcer recurrence, one should carefully consider all options before performing partial gastrectomy since gastric emptying rate after these consecutive procedures worsens considerably.

Comparison of anterior and geometric mean liquid and solid gastric emptying rates in dogs and in patients after partial gastrectomy.

OBJECTIVE: The purpose of this study was to determine if geometrical correction is necessary in the study of gastric emptying rate (GER) for liquids, using a low-energy radionuclide, such as 99mTc. Solid test meals were considered the reference. METHODS: Both solid and liquid GERs were investigated using regional analysis. Anterior data were compared with geometrically corrected values in 15 dogs and 9 partial gastrectomy patients. RESULTS: Anterior and geometrically corrected measurements differed significantly for solid food in the whole gastric region and in the antrum. Geometrically corrected values differed slightly from anterior data after partial gastrectomy. No difference was found for liquid food. Liquids redistributed much faster than solids within the stomach. CONCLUSION: Measurement of GER using a single-phase liquid meal does not require geometrical correction. This is due to the rapid intragastric redistribution of the liquid. Geometrical correction for solid food can be omitted only after partial gastrectomy.

Gastric emptying rate measurement after vertical banded gastroplasty.

BACKGROUND: In vertical banded gastroplasty (VBG), a small proximal gastric pouch is created, which is believed to fill rapidly and to empty slowly. METHODS: In 13 patients who underwent VBG, gastric emptying rate was measured. A radiolabelled solid test meal was used before and 2 weeks after operation. From a region of interest above the whole stomach, the proximal pouch and the distal stomach, half emptying time as well as retention percentage were derived. RESULTS: All patients experienced early satiety and gastric fullness after ingestion of a small test meal. The proximal pouch emptied rapidly. The evacuation of the test meal from the whole gastric region as well as the distal stomach were not altered significantly by the operation. CONCLUSION: VBG is a safe operation which reduced weight significantly. Early satiety, however, induced by this technique, cannot be explained alone by slow emptying of the proximal pouch. The nature of the outlet of the pouch as well as the behavior of its wall must be considered.

Gastric emptying of liquid meals after anterior gastric stapling and posterior truncal vagotomy in beagle dogs: discrepancy with results for solid food.

BACKGROUND/AIMS: Since the development of highly selective vagotomy (HSV), simplified procedures such as posterior truncal vagotomy with anterior gastric wall stapling (PTV-AGS) became available to achieve parietal cell denervation. The purpose of this investigation was to detect possible gastric emptying disturbances due to complete vagotomy of the posterior gastric wall and to stapling of the anterior stomach wall. METHODOLOGY: Six female dogs, undergoing HSV, were compared with six others, in which PTV-AGS was performed. Radionuclide labeled liquid test meals were used to evaluate gastric emptying rate (GER) and results were compared with solid test meal emptying. RESULTS: A small, statistically insignificant fastening of liquid gastric emptying was seen early after HSV, as well as after PTV-AGS, and persisted one year after operation. There proved to be a striking lack of correlation between the GER-results after liquid versus solid meals. CONCLUSION: Just as after HSV, gastric emptying rates of liquid meals after PTV-AGS do not show a statistical difference as compared with preoperative values. Both operations therefore do not induce clinically important gastric motility changes. Separate test meals with liquid and solid food prove to be necessary in order to detect such changes.

Merkel cell carcinoma: the use of surgery and radiotherapy for locoregional control.

Merkel cell tumours are rare skin cancers with an unpredictable clinical course. Correct diagnosis requiring immunohistochemical staining is essential since the treatment differs entirely from that of basalioma. Locally limited disease as well as rapidly fatal course have been observed. In a small series of 5 patients and from literature data, surgery continued with radiotherapy for locoregional control is advocated as optimal approach since this type of tumour can behave differently compared to basal cell carcinomas.

Comparison of radionuclide labelled test meals versus endoscopy in the preoperative assessment of the gastric outlet patency.

A series of 39 patients with peptic ulcer disease is investigated with respect to gastric outlet obstruction. Two diagnostic tools are compared, namely endoscopy and evaluation of radionuclide meal emptying. Endoscopic obstruction was qualified as non passage of a 14 mm gastroscope. Gastric emptying reduction was considered clinically relevant when half emptying times exceeded 60 minutes for solids and 12 minutes for liquids. Comparison of both techniques of radionuclide meal emptying with endoscopy showed a poor correlation (accuracy 15/28), especially when liquid gastric emptying versus endoscopy was concerned.

Pancreatic secretion after anterior gastric wall stapling with posterior truncal vagotomy in dogs.

Anterior gastric stapling with posterior truncal vagotomy has previously been investigated for its effect on canine gastric acid reduction and motility. Posterior truncal vagotomy could, however, induce reduced pancreatic function, which has been observed after total abdominal vagotomy. In this study, pancreatic secretion has been investigated after anterior gastric stapling with posterior truncal vagotomy in a series of canine experiments by means of a stimulation test. On the long term, no significant postoperative reduction of exocrine pancreatic secretion was observed.

Anterior gastric wall stapling combined with posterior truncal vagotomy in the treatment of duodenal ulcer.

Anterior gastric stapling with posterior truncal vagotomy was examined as an alternative to highly selective vagotomy in the treatment of peptic ulcer disease. A clinical series of 32 patients who underwent the combined procedure is presented; gastric acid output was adequately reduced (basal output by 82 per cent, peak by 64 per cent). Motility changes were temporary and mild. Clinical follow-up, using a modified Visick grading, showed good to excellent results in 21 of 25 patients who could be classified. This procedure is suggested as an appropriate alternative to highly selective vagotomy.

Comparison of the effect of conventional highly selective vagotomy and anterior gastric wall stapling with posterior truncal vagotomy on the gastric emptying rate for solid meals in beagle dogs.

Anterior gastric wall stapling combined with posterior truncal vagotomy has been used as a new and adequate gastric acid output-reducing procedure. Severing the posterior vagal trunk as well as stapling the anterior gastric wall could impair gastric emptying. In this study, the gastric emptying rate for solid food, using a radionuclide technique, has been evaluated in 2 series of canine experiments. Compared to the results after conventional highly selective vagotomy, a temporary delay in the gastric emptying rate could be found after this new procedure, however, completely normalizing 1 year later.

Gastric emptying for solids in patients with duodenal ulcer before and after highly selective vagotomy.

In a series of 31 duodenal ulcer patients (23 males and 8 females), who underwent a highly selective vagotomy, gastric emptying characteristics of a solid meal, labeled with [99mTc]stannous colloid, were assessed before, two weeks and six months after operation. The clinical diagnosis was confirmed by endoscopy and x-ray; failure of treatment with H2 antagonists or antacids during 1-18 (mean 5) years was the direct indication for operative treatment. A temporary delay in gastric emptying is noted two weeks after operation (T1/2: 124 vs 57 min). After six months, gastric emptying time has practically normalized. It appears that this is the result of the preservation of the antropyloric vagal nerve supply. In these patients, a 10% recurrence rate is noted, comparable to the results in the literature. Highly selective vagotomy proves to be a safe and effective procedure with few side effects. It does not impair gastric motility.

Gastric emptying of liquids after highly selective vagotomy for duodenal ulcer.

In a group of clinical patients with duodenal ulcer submitted to highly selective vagotomy, gastric emptying studies were performed pre-operatively and 2 weeks and 6 months after surgery. A standard liquid meal labeled with radioactive technetium was used for scanning. In this group of duodenal ulcer patients, no abnormal emptying was noted prior to surgery as compared with controls. After highly selective vagotomy, the gastric emptying time for liquids was statistically shorter as compared with preoperative values. It is concluded that highly selective vagotomy may be the operative treatment of choice for duodenal ulcer patients with respect to acid secretion, but that it alters gastric motility and emptying significantly.