Prophylactic repair of renal artery stenosis is not justified in patients who require infrarenal aortic reconstruction

Purpose: Simultaneous prophylactic repair of asymptomatic renal artery stenosis (ARAS) in patients who require infrarenal aortoiliac reconstruction is controversial. This study documents the natural history of ARAS in patients who require aortic reconstruction. Methods: Two hundred patients who required aortic reconstruction from 1985 to 1990 for indications other than hypertension or renal salvage were identified. ARAS was not repaired. Preoperative angiograms were available for 171 of 200 patients and were reviewed for renal artery stenosis. Patients were assessed for atherosclerotic risk factors, survival, preoperative and follow-up blood pressure, serum creatinine level, antihypertensive medication usage, and need for dialysis. Results: The mean duration of follow-up was 6.3 years. Twenty-four of 171 patients (14%) had preoperative unilateral 70% to 99% diameter reduction ARAS, and eight (5%) had bilateral 70% to 99% ARAS. Clinical features associated with ≥70% ARAS included coronary artery disease, increased age, and a diagnosis of hypertension (p < 0.05). Patients with ≥70% ARAS did not have a decreased 7-year survival rate (66% vs 84%; p = 0.10) but had higher systolic blood pressures (153 ± 25 vs 138 ± 30 mm Hg; p < 0.05) as well as increased numbers of antihypertensive medications at follow-up (1.1 ± 0.2 vs 0.7 ± 1; p < 0.05). The mean serum creatinine level (1.1 ± 0.3 preoperative vs 1.4 ± 0.8 mg/dl; p = NS) was not increased. One patient (0.58%) with polycystic kidney disease and minimal renal artery stenosis required dialysis. Conclusions: High-grade ARAS in patients who are undergoing infrarenal aortic reconstruction is associated at late follow-up with increased systolic blood pressure and a need for increased numbers of antihypertensive medications, but not decreased survival rate, dialysis dependence, or an increase in serum creatinine level. These data do not support renal artery repair in patients with ARAS who undergo infrarenal aortic reconstruction. (J Vasc Surg 1998;28:14-22.)     

Renal endarterectomy vs. bypass for combined aortic and renal reconstruction: Is there a difference in clinical outcome?

Are there differences in the patient characteristics and clinical outcome for transaortic renal endarterectomy vs. bypass grafting when either technique is combined with infrarenal aortic replacement for occlusive or aneurysmal disease? Two common perceptions persist: (1) combined aortic and renal procedures have a high risk and (2) bypass is easier and safer than endarterectomy. To address these controversies we compared 52 consecutive patients undergoing concomitant aortic and renal reconstruction between 1987 and 1991: 26 with bypass and 26 with endarterectomy. Bypass patients were older (70 vs. 64 years,p=0.001),had more extensive plaque extending into the distal renal artery and more severe baseline azotemia (creatinine=2.6 vs 1.7 mg/dl,p=0.01),more clinically evident coronary heart disease (89% vs. 56%,p=0.001),and a greater need for nephrectomy of a small nonfunctional pressor kidney (23% vs. 0%) than endarterectomy patients. In contrast, endarterectomy patients more commonly required aortic replacement for occlusive disease than for an aortic aneurysm (endarterectomy: 65% vs. 35%; bypass: 19% vs 81%,p=0.002)and tended to require more intraoperative technical revisions (12% vs. 4%) than bypass patients. Both groups, however, experienced no operative mortality, had similar cardiorespiratory morbidity, and achieved equal improvement in hypertension (69% vs. 65%). Bypass patients, who already had more severe preoperative azotemia than endarterectomy patients, showed less improvement in the creatinine level (Cr=2.1 vs. 1.4 mg/dl,p=0.01)and had greater need for late dialysis (30% vs. 4%,p=0.01).Only one patient on dialysis had graft occlusion. We conclude that patients requiring bypass are generally at a more advanced stage of both cardiovascular and renal disease and have a greater need for late dialysis than was previously recognized. Transaortic endarterectomy is a safe and effective choice in patients with bilateral orificial renal atheroma and aortic occlusive disease. Both procedures currently carry a lower operative risk than was previously predicted and have equal effectiveness in controlling renovascular hypertension.     

Coronary artery bypass grafting in type II diabetic patients: a comparison between insulin-dependent and non-insulin-dependent patients at short- and mid-term follow-up

Background

Diabetes is a well-established risk factor for coronary artery disease, and it is associated with an increased rate of early and late adverse events after myocardial revascularization by coronary artery bypass grafting.

Methods

A prospective follow-up study was done to evaluate the short-term and mid-term outcomes of type II diabetic patients who had coronary artery bypass grafting at our institution between 1996 and May 1999. A total of 200 patients, 100 insulin-dependent diabetic patients (group I) and 100 non-insulin-dependent diabetic patients (group II), met the inclusion criteria of the study and were included in the clinical follow-up study.

Results

The characteristics of the patients of the two groups were similar for baseline clinical angiographic and operative characteristics. In particular, no significant differences in cardiopulmonary bypass and aortic cross-clamping times were noted between the two groups. The number grafts per patient was similar between the two groups. There were no in-hospital deaths, but postoperative complications were different among the two series. In fact, 33% of patients in group I had at least one major complication compared with 20% in group II (p = 0.037). The cumulative number of complications was 148 in group I and 69 in group II, and the mean number of complications per patient was 4.5 and 3.5 in groups I and II, respectively. The major differences in perioperative complication rates were found in the need for prolonged (> 24 hours) ventilation, occurrence of respiratory or renal insufficiency, and mediastinitis. The mean length of stay in the intensive care unit and for total hospitalization were longer in group I than group II (4.3 ± 2.8 days versus 2.8 ± 2.7 days [p = 0.010] and 11.1 ± 2.2 days versus 7.2 ± 2.4 group II [p < 0.05], respectively). At long-term follow-up, group I patients had a significantly higher mortality rate (29% versus 10%, p < 0.001). Moreover, overall late cardiac and noncardiac complication rates were significantly higher in group I than II (37% versus 22%, p = 0.02). In the multivariate analysis including several preoperative and operative variables, treatment by insulin, advanced age (> 75 years), left ventricular dysfunction (left ventricular ejection fraction < 35%), and complex lesions at coronary angiography (American Heart Association lesion classification type C lesion) were found as independent predictors of increased mortality.

Conclusions

Our data show that patients with insulin-dependent type II diabetes who had coronary artery bypass grafting have a significantly higher rate of major postoperative complications with an extremely unfavorable short- and long-term prognosis. Diabetic patients on insulin treatment should be considered high-risk candidates for coronary artery bypass grafting and require intense perioperative and long-term monitoring. Further studies will be necessary to investigate whether such conclusions may be appropriate for newer surgical strategies such as off-pump operation.     

Increased Incidence of Renal Cysts in Patients with Abdominal Aortic Aneurysms: A Common Pathogenesis?

We have empirically observed that patients with abdominal aortic aneurysms (AAAs) seem to have an increased incidence of renal cysts on computed tomography (CT). In order to evaluate this possible association, a retrospective cohort study was conducted comparing the incidence of renal cysts on CT scan in 100 patients with AAA to 100 patients without AAA (matched by age and gender). Univariate analysis and multiple logistic regression were performed to evaluate the association of AAAs and other risk factors with the presence of renal cysts. Of patients with AAAs, 54% had renal cysts compared to only 30% in the control group (p = 0.0006, relative risk = 2.73). The AAA group had a higher incidence of chronic obstructive pulmonary disease (COPD, 14% vs. 1%), hypertension (76.6% vs. 46.5%), coronary artery disease (38.3% vs. 12%), and hypercholesterolemia (41.5% vs. 9.1%) compared to the non-AAA group. There was a significant linear correlation between renal cysts and COPD (p = 0.011), the presence of AAA (p = 0.0005), and age (p = 0.019), whereas hypercholesterolemia (p = 0.059) and diabetes (p = 0.063) approached significance. On multivariate analysis, there were three independent predictors of renal cysts: COPD (p = 0.051), age (p = 0.01), and AAA (p = 0.028). In conclusion, there is a significantly higher incidence of renal cysts in patients with AAA compared to patients without AAA. To our knowledge, this association has not previously been reported. Future studies are needed to determine whether this correlation is the result of a commonality in the pathogenesis of AAA and renal cysts.     

Utility of clinical pathway and prospective case management to achieve cost and hospital stay reduction for aortic aneurysm surgery at a tertiary care hospital

Purpose: We reviewed our experience with a clinical pathway instituted in December 1993 for all nonurgent abdominal aortic aneurysm (AAA) surgery.Methods: We analyzed a reference group of 49 consecutive pre-pathway AAA patients (group I) and the 44 patients enrolled in the first year of the pathway (group II). On the basis of the interim review of data collected during the first year, pathway modifications were made, and 34 patients enrolled after these modifications (group III) were also analyzed.Results: Comparison of groups I and II showed that institution of the pathway resulted in a marginally significant reduction in mean charges of 14.7% ( p = 0.09), and a slight fall in mean length of stay (LOS) (13.8 vs 13.1 days, NS) and mortality rate (4.1% vs 2.3%, NS). For group II, a significant correlate ( p < 0.05) of increased charges was fluid overload as diagnosed by chest radiograph. This recognition led to active efforts to reduce perioperative fluid administration. Comparison of groups II and III revealed that the practice modifications led to marked reduction in the incidence of fluid overload (73% vs 24%; p < 0.01), mean charges (30.4% reduction; p < 0.05), mean LOS (13.1 vs 10.2 days; p < 0.05), and median LOS (11 vs 8 days). Multiple regression analysis of all pathway patients showed that preoperative renal insufficiency is a significant predictor of both increased LOS ( p < 0.01) and charges ( p < 0.01), but that age, sex, and coronary disease were not predictive. Of the postoperative parameters analyzed, important correlates of increased charges were acute renal failure ( p < 0.01) and fluid overload ( p < 0.01).Conclusions: Institution of a clinical pathway for AAA repair resulted in significant charge reduction and a slight reduction in stay. Practice modifications based on interim data analysis yielded further significant reductions in charges and LOS, with overall per-patient charge savings (group I vs III) of 40.6% ( p < 0.05) and overall LOS reduction of 3.5 days ( p < 0.05). The reduction in actual charges was seen despite an overall increase in the hospital rate structure. Comparing groups I, II, and III, we found no indication of increasing mortality rate. Ongoing analysis has identified correlates of increased charges, potentially permitting identification of high-cost subgroups and more focused cost-control efforts. Rather than restricting management, clinical pathways with periodic data analysis may improve quality of care. (J Vasc Surg 1997;25:84-93.)     

Long-term survival and late complications after repair of ruptured abdominal aortic aneurysms

Purpose:Long-term survival and late vascular complications in patients who survived repair of ruptured abdominal aortic aneurysms (RAAA) is not well known. The current study compared late outcome after repair of RAAA with those observed in patients who survived elective repair of abdominal aortic aneurysms (AAA). Methods:The records of 116 patients, 102 men and 14 women (mean age: 72.5 (8.3 years), who survived repair of RAAA (group I) between 1980 to 1989 were reviewed. Late vascular complications and survival were compared with an equal number of survivors of elective AAA repair matched for sex, age, surgeon, and date of operation (group II). Survival was also compared with the age and sex-matched white population of west-north central United States. Results:Late vascular complications occurred in 17% (20/116) of patients in group I and in 8% (9/116) in group II. Paraanastomotic aneurysms occurred more frequently in group I than in group II (17 vs. 8,p = 0.004). At follow-up, 32 patients (28%) were alive in group I (median survival: 9.4 years) and 53 patients (46%) were alive in group II (median survival: 8.7 years). Cumulative survival rates after successful RAAA repair at 1, 5, and 10 years were 86%, 64%, and 33%, respectively. These were significantly lower than survival rates at the same intervals after elective repair (97%, 74%, and 43%, respectively, p = 0.02) or survival of the general population (95%, 75%, and 52%, respectively,p < 0.001). Coronary artery disease was the most frequent cause of late death in both groups. Vascular and graft-related complications caused death in 3% (3/116) in group I and 1% (1/116) in group II. Cox proportional hazards modeling identified age p = 0.0001), cerebrovascular disease p = 0.009), and number of days on mechanical ventilation p = 0.01) to be independent prognostic determinants of late survival in group I. Conclusions:Late vascular complications after repair of RAAA were higher and late survival rates lower than after elective repair. These data support elective repair of AAA. As two-thirds of the patients discharged after repair of RAAA are alive at 5 years, aggressive management of RAAA remains justified. (J Vasc Surg 1998;27:813-20.)     

Long-term coronary artery outcome after arterial switch operation for transposition of the great arteries

Objective: To analyse the long-term patency of coronary arteries after neonatal arterial switch operation (ASO). Methods: A retrospective study of the operative reports, follow-up and postoperative catheterisation data of 119 patients, who underwent the great arteries (TGA) repair since 1991, has been carried out. Patient population: Among the 133 survivors of the 137 ASOs performed between 1991 and 2007, 119 patients have been studied by routine control cardiac catheterisation and form the study population. Median time between repair and the coronary angiography was 2.9 ± 1.9 years. A comparison between the eight patients (6.7% out of the entire study population), known to have postoperative coronary obstructions (group I) and the rest of the cohort with angiographic normal coronary vessels (group II) was performed by univariate analysis of variance and logistic regression models. One patient had surgical plasty of the left coronary main stem with subsequent percutaneous angioplasty, three patients had primary coronary stent implantation and four patients had no further intervention at all. In group I, all but one patient denied symptoms of chest pain and echocardiography failed to show any difference between the two groups in terms of left ventricular systolic function (ejection fraction group I 61 ± 2% vs 62 ± 6% of group II, p = 1.0). Results: The association of coronary obstruction with complex native coronary anatomy (Yacoub type B to E) was evident at both univariate (62% of group I vs 22% of group II, p = 0.04) and logistic regression (p = 0.007, odds ratio (OR) 8.1) models. The type of coronary reimplantation (i.e., coronary buttons on punch vs trap-door techniques) was similar between the two groups (punch reimplantation in 25% of patients of group I vs 31% of group II, p = 0.1) as was the relative position of the great vessels (aorta anterior in 100% of patients of group I vs 96% of group II; univariate, p = 0.1). Conclusions: The late outcome in terms of survival and functional status after ASO is excellent. Nevertheless, the risk of a clinically silent late coronary artery obstruction of the reimplanted coronary arteries warrants a prolonged follow-up protocol involving invasive angiographic assessment.     

Presentation and patterns of aortic aneurysms in young patients

Purpose: Although aortic aneurysm (AA) is primarily a disease of older age groups, younger (<51 years) patients infrequently are admitted requiring AA surgery. We sought to compare the characteristics of these patients with those of a randomly selected group of older patients with AA.Methods: We identified 26 patients with AA (group I) under age 51 (mean age 44.8) treated surgically between 1977 and 1993, after excluding patients with acute aortic dissection, traumatic pseudoaneurysms, and ascending or arch aneurysms, and compared them with 75 randomly selected patients with AA between the ages of 65 and 75 (mean age 70.3) who were surgically treated during the same time period (group II).Results: Prevalence of hypertension, diabetes, coexisting heart, kidney, or occlusive peripheral vascular disease was similar between the two groups, and familial aneurysm rates and sex distribution did not differ significantly. More patients in group I had symptoms at the time of presentation (46% vs 6.7%, p < 0.001), and they also had larger AAs (6.9 cm vs 6.0 cm, p = 0.01). Definable causes of aneurysmal disease, such as Takayasu's, Cogan's, and Marfan syndromes, were more common among the young patients (23% vs 0%, p = 0.01), but most (77%) young patients did not have an identifiable syndrome associated with their aneurysm disease. Group I had a marked shift toward proximal aneurysms, defined as involvement of juxtarenal, suprarenal, or thoracoabdominal aorta (46% vs 18% in group II, p < 0.01). This difference persisted even when aneurysms associated with the above syndromes were excluded from consideration (p = 0.02). Cigarette smoking was much more common among the young patients (83% vs 51% in group II, p < 0.01). Smoking in group II was associated with more extensive aneurysm disease (p = 0.04).Conclusions: Aneurysmal disease presenting in the young adult is more likely to be symptomatic and associated with more proximal aortic involvement than aneurysmal disease in older patients. Smoking appears to play an important role in the pathogenesis of aneurysmal disease in the young patient and was associated in our study with more proximal aneurysms among older patients. A subgroup of patients at risk for early and aggressive aneurysm disease is suggested by these data. (J VASC SURG 1994;20:880-8.)     

Endovascular Abdominal Aortic Aneurysm Repair Using the AneuRx<Superscript>®</Superscript> Stent Graft: Impact of Excluding Accessory Renal Arteries

The aim of this study was to evaluate clinical sequelae of accessory renal artery exclusion during endo-AAA repair. Medical records and pre- and postoperative CT scans were reviewed from 114 AAA patients treated with the AneuRx^® stent graft between 1996-2001. Thirty-seven accessory renal arteries were identified in 32/114 patients (28%) with 19/32 patients having infrarenally located accessory renal arteries. In group I (11 patients), the stent graft excluded 11 accessory renal arteries. In group II (8 patients), eight accessory renal arteries were not excluded. Average infrarenal neck length was 24.9 mm in group I vs. 30.7 mm in group II (p = 0.07). The average length of device seal was similar in both groups (19.4 vs. 18.5 mm, p = 0.67). There were no perioperative deaths, significant postoperative hypertension, rise in serum creatinine, or postoperative renal infarctions in either group. Three of eight patients (38%) in the non-excluded group developed type I proximal endoleaks whereas none in the excluded patient group did (p = 0.06). Accessory renal arteries may be safely excluded during endovascular AAA repair and may result in a more secure proximal device fixation. Presented at the Annual Meeting of the Southern California Vascular Surgical Society, Carlsbad, CA, April 11-13, 2003     

Improvement in results of repair of type IV thoracoabdominal aortic aneurysms

Purpose: Although management of extensive type I and II thoracoabdominal aortic aneurysms (TAA) remains a formidable challenge, results of repair of TAA originating in the distal thoracic aorta (type IV) appear to have improved significantly. To quantitate this perceived improvement, the following retrospective study was undertaken to examine the results of type IV TAA repair at the Brigham & Women's Hospital over the past 18-year period.Methods: From July 1977 to September 1994, nonruptured atherosclerotic type IV TAAs were repaired in 58 patients. The mean age was 70 years, and associated risk factors included smoking (91%), hypertension (86%), coronary artery disease (52%), and previous aortic surgery (38%). Mean follow-up was 2.4 years (median 2 years).Results: Overall 30-day mortality was 5.3% (two deaths). Morbidity included stroke (3.5%), paraplegia (1.8%), permanent paraparesis (1.8%), myocardial infarction (7%), pneumonia (8.8%), gastrointestinal bleeding (11%), intestinal ischemia (5.3%), wound infection (7.0%), peripheral ischemia (5.3%), in-hospital dialysis (8.8%), and permanent dialysis (1.9%). Overall 5-year survival was 50%. With univariate analysis, survival was positively correlated with more recent year of operation (p = 0.002), smaller volume of intraoperative blood transfusion ( p = 0.02), decreased supraceliac ischemia time ( p = 0.04), and the use of the retroperitoneal approach ( p = 0.09). Multiple regression analysis revealed that the year of operation was the only independent predictor of survival ( p = 0.003). Subgroup analysis of patients who underwent operation between 1977 and 1987 (n = 13) and 1988 and 1994 (n = 45) revealed statistically significant improvements in length of hospital stay (46 + 12 vs 21 + 4 days, p = 0.02), postoperative dysrhythmia (50% vs 16%, p = 0.03), pstoperative maximum serum glutamic oxaloacetic-transaminase (516 + 234 vs 319 + 139 mg%, p = 0.04), incidence of hemorrhage requiring reexploration (33% vs 0%, p = 0.002), 30-day mortality (23% vs 0%, p = 0.009), and in-hospital mortality (39% vs 2.2%, p = 0.002).Conclusions: The modern mortality, morbidity, and survival of surgical repair of type IV TAA in our institution approaches that of infrarenal abdominal aortic aneurysm. (J Vasc Surg 1996;24:74-81.)     

The durability of different reconstructive techniques for atherosclerotic renal artery disease

Purpose: Among various surgical techniques for renal artery reconstruction (RAR), anatomic aortorenal bypass has been the preferred standard. Yet concern regarding origin of the bypass from a diseased aorta and desire to avoid a major aortic operation in these patients who are often at poor risk has led to increasing use of extraanatomic bypass grafting, particularly hepatorenal and splenorenal bypass. This study was conducted to compare the safety and long-term performance of these different techniques of renal artery reconstruction.Methods: We reviewed a 15-year (1976 to 1991) experience with 323 surgical RAR performed in 285 patients with atherosclerotic renovascular disease. Long-term patency and survival rates were analyzed by life-table methods. Variables potentially affecting early failure of the RAR and perioperative and late mortality rates were examined by Cox proportional hazards models.Results: Diffuse atherosclerosis characterized the patients' clinical profile. Clinically evident coronary artery disease was present in 54% of patients, and some degree of renal insufficiency was present in 60%. Ninety-five percent of patients had hypertension with poor control of hypertension seen in 50%. Aortic disease necessitated combined aortic grafting and RAR in 43% of the study group. Various techniques of RAR were used as follows: endarterectomy or patch angioplasty, 8.5%; extraanatomic bypass grafting, 37% (hepatorenal, 62; splenorenal, 52; iliorenal, 7); and aortorenal bypass grafting, 54% (native aorta, 34; combined aortic graft and RAR, 140). Early failure of the RAR occurred in 5% of cases, and the operative mortality rate for the entire cohort was 5.6%. Median follow-up duration was 9.4 years. A comparison of early and late patency for the major types of RAR revealed equivalent ( p = 0.44) performance of aortorenal and extraanatomic bypass grafting. Perioperative complications occurred more frequently ( p < 0.02) in patients undergoing combined operations. The cumulative 5-year survival rate for all patients was 75%.Conclusions: Because extraanatomic bypass grafting can provide long-term results equivalent to aortorenal bypass grafting, the choice among techniques for RAR in patients with diffuse atherosclerosis should be based on both technical and operative safety considerations, rather than adherence to aortorenal bypass grafting as an inherently superior technique. (J V ASC S URG 1994;20:76-87.)     

CORONARY ARTERY DISEASE AMONG DIABETIC AND NON-DIABETIC PATIENTS WITH END STAGE RENAL DISEASE

Cardiovascular disease is the major cause of death among patients with end stage renal disease and accounts for about half the deaths among the dialysis population. Several researchers have reported a high prevalence of coronary artery disease among diabetic patients with renal failure and coronary arteriography is often considered an integral part of the pretransplant evaluation of diabetic patients with end stage renal disease. However, very few reports have addressed the question of coronary disease in non-diabetic patients, and the pattern and prevalence of coronary artery disease in non-diabetic patients with end stage renal disease are not well defined. We evaluated the clinical and coronary angiographic findings in 158 consecutive patients (84 diabetic and 74 non-diabetic) with end stage renal disease. The coronary arteries were divided into 16 segments and each segment was analyzed for the presence of coronary disease, which was defined as the presence of ≥ 50% luminal diameter stenosis. Diabetic patients had more adverse risk factors for coronary artery disease, yet there was no significant difference in the prevalence of coronary artery disease between the diabetic and non-diabetic patients (67% vs. 55%, p = 0.15), or in the number of affected coronary artery segments (2.0 vs. 1.4, p = 0.05). Triple vessel coronary artery disease was however, significantly more common among the diabetic subjects (27% vs. 12%, p = 0.005). Non-diabetic patients with end stage renal disease also have a high prevalence of coronary artery disease and may merit as careful investigation of their coronary status as their diabetic counterparts.     

On-pump beating-heart versus conventional coronary artery bypass grafting for revascularization in patients with severe left ventricular dysfunction: early outcomes

Background

We sought to evaluate the effects of on-pump beating-heart versus conventional coronary artery bypass grafting techniques requiring cardioplegic arrest in patients with coronary artery disease with left ventricular dysfunction.

Methods

We report the early outcomes associated with survival, morbidity and improvement of left ventricular function in patients with low ejection fraction who underwent coronary artery bypass grafting between August 2009 and June 2012. Patients were separated into 2 groups: group I underwent conventional coronary artery bypass grafting and group II underwent an on-pump beating-heart technique without cardioplegic arrest.

Results

In all, 131 patients underwent coronary artery bypass grafting: 66 in group I and 65 in group II. Left ventricular ejection fraction was 26.6% ± 3.5% in group I and 27.7% ± 4.7% in group II. Left ventricular end diastolic diameter was 65.6 ± 3.6 mm in group I and 64.1 ± 3.2 mm in group II. There was a significant reduction in mortality in the conventional and on-pump beating-heart groups (p < 0.001). Perioperative myocardial infarction and low cardiac output syndrome were higher in group I than group II (both p < 0.05). Improvement of left ventricular function after the surgical procedure was better in group II than group I.

Conclusion

The on-pump beating-heart technique is the preferred method for myocardial revascularization in patients with left ventricular dysfunction. This technique may be an acceptable alternative to the conventional technique owing to lower postoperative mortality and morbidity.     

The impact of a short interval (≤1 year) between primary and reoperative coronary artery bypass grafting procedures

Reoperative (redo) coronary artery bypass grafting is an efficient treatment for patients with progressive coronary artery disease and those with conduit failure. Previous studies have demonstrated that a short time interval between primary and redo coronary artery bypass grafting is associated with a significantly higher mortality rate. In the present report this particular group have been specifically evaluated. Between 1 January 1990 and 1 October 1994, 383 consecutive patients underwent redo coronary artery bypass grafting. Thirty-three patients (8.6%) were operated on at ≤1 year (group I) and 350 patients at >1 year after the primary bypass (group II). The main indications for redo in group I were graft failure (58%), incomplete revascularization (39%) and progress of disease (3%); respective values in group II were 26%, 15%, and 23%. In addition, 36% of patients in group II had combinations of complications. Patient characteristics did not differ between groups, except a higher incidence of insulin-dependent diabetes in group I (P < 0.05). There was a higher incidence of left main stem stenosis of >70% in group I (P < 0.05). Group I patients had a longer aortic cross-clamping time and needed thromboendarterectomy and patching of coronary vessels more often than did those in group II (P < 0.05). The internal mammary artery had been more frequently used at the primary coronary artery bypass grafting in group I (P < 0.01). The overall mortality rate was 8.9%; that in group I was 18% and in group II, 8% (P < 0.05). There was a higher incidence of non-fatal myocardial infarction and a need for prolonged ventilatory support (>24 h) in group I. Other postoperative complications did not differ. Significant risk factors for mortality in group I were preoperative Canadian Cardiovascular Society class ≥3, unstable angina, need for urgent operation and left ventricular ejection fraction <40%, and ≥70% left main stem stenosis. In group II, the risk factors were: unstable angina, urgent operation, left ventricular ejection fraction <40%, internal mammary artery not used at primary coronary artery bypass grafting and the need for coronary thromboendarterectomy. The 3-year survival and cardiac event-free survival did not differ between the groups. This study has confirmed that early redo coronary artery bypass grafting (≤1 year from primary bypass) is associated with an increased operative risk. Copyright © 1996 The International Society for Cardiovascular Surgery.     

Neurologic deficit in patients at high risk with thoracoabdominal aortic aneurysms: The role of cerebral spinal fluid drainage and distal aortic perfusion

Purpose: This prospective study evaluated the possible prevention of postoperative neurologic deficit in patients at high risk with thoracoabdominal aortic aneurysms (TAAA), types I and II, by use of perioperative cerebrospinal fluid drainage and distal aortic perfusion. Methods: Between September 18, 1992, and August 8, 1993, 45 consecutive patients underwent TAAA repair (14 type I, 31 type II). Thirty-six were men and nine were women. The median age was 63 years (range 28 to 88). Twenty-four of 45 patients (53%) had dissection and 17 of 45 (38%) had prior proximal aortic replacement. All patients underwent perioperative cerebrospinal fluid drainage and distal aortic perfusion. Median aortic clamping time was 42 minutes. Thirty-five of 45 patients (78%) underwent intercostal artery reattachment. Results: The 30-day survival rate was 96% (43 of 45 patients). Early neurologic deficit occurred in two of 45 patients (4%), and late neurologic deficit also occurred in two of 45 patients (4%). We compared the neurologic deficit of our current group of 45 patients with the data of a previously unpublished study of 112 patients also from this center. Total neurologic deficit for the current group was four of 45 (9%) versus the previous group of 35 of 112 (31%) with a p value of 0.0034 (Pearson chi-square test). Neurologic deficit for patients with type I TAAA was 0 of 14 (0%) versus 15 of 73 (21%) (p = 0.062); for patients with type II TAAA 4 of 31 (13%) versus 20 of 39 (51%) (p = 0.0008). In patients with aortic dissection, neurologic deficit was 3 of 24 (12%) versus 9 of 32 (28%) (p = 0.0304); no dissection was 1 of 21 (5%) versus 26 of 80 (32%) (p = 0.011). For aortic clamp times less than 45 minutes, neurologic deficit was 1 of 24 (4%) versus 14 of 68 (21%) (p = 0.061); for aortic clamp times equal to or greater than 45 minutes, neurologic deficit was 3 of 21 (14%) versus 21 of 44 (48%) (p = 0.0090). Conclusion: Neurologic deficit in patients treated for types I and II TAAA was reduced significantly by perioperative cerebral spinal fluid drainage and distal aortic perfusion. (J VASC SURG 1994;20:434-43.)     

Perirenal Fixation as an Independent Factor in Aortic Remodeling after Endovascular Aortic Aneurysm Repair

The purpose of our study was to evaluate the influence of perirenal fixation of endovascular aortic grafts on the rate of endoleak and aortic sac remodeling. Retrospective analysis of all patients (pts.) after undergoing endovascular aortic aneurysm repair (EVAR) at our institution was performed. Pre- and postoperative aortic dimensions were obtained from CT scans and angiograms. Intraoperative angiograms were reviewed and patients grouped by the proximity of the graft to the lowest renal arteries: group I: flush with the lowest renal artery; group II: 5 mm distal to lowest renal artery; and group III: >5 mm distal to lowest renal artery. Of the 96 grafts placed between 2000 and 2002, 44 were AneuRx (Medtronic, Santa Rosa, CA) and 52 were Ancure (Guidant, Menlo Park, CA) devices. There were 39 pts. in group I, 42 in group II, and 11 in group III (data on 5 pts. were not obtained). At 6 months, the mean decrease in sac diameter for all groups was 0.42 ± 0.08 cm (I: 0.56 ± 0.11 cm; II: 0.38 ± 0.11 cm; III: 0.6 ± 0.15 cm). There was no significant difference between each group. When perirenal fixation (group I) was compared with nonperirenal fixation (groups II and III), there was a significant difference in sac shrinkage at 6 months (p < 0.05, ANOVA). Group I had shorter necks and smaller aneurysms (2.2 ± 0.1 cm and 5.3 ± 0.1 cm) than those of groups II and III (2.7 ± 0.1 cm and 5.7 ± 0.1 cm, p < 0.05, ANOVA). There was no difference in aortic neck diameter or in aortic neck diameter to graft ratio. When controlled for the variables studied (AAA diameter, length of neck, diameter of neck, diameter of neck to graft ratio, and any endoleak by 6 months), logistic regression analysis identified perirenal fixation as the only significant factor in aortic sac shrinkage of >0.4 cm by 6 months (odds ratio = 16, p < 0.01). With the same variables, a linear regression model also identified perirenal fixation as the only predictive factor in aortic shrinkage (regression coefficient = 0.46, p < 0.05). The endoleak-free survival rate with perirenal fixation was 96 ± 5% and without it was 80 ± 7% (Kaplan Meier, p = 0.09, log rank). Perirenal placement of endovascular grafts is associated with a trend toward fewer endoleaks, and improved aortic sac shrinkage independent of aortic neck length, AAA diameter, diameter of neck, and endoleak. Failure to achieve perirenal placement of EVAG increased the likelihood of reduced or failed aortic sac shrinkage in this series.Presented at the Twenty-eighth Annual Meeting of the Peripheral Vascular Surgery Society, Chicago, IL, June 7, 2003.     

Pediatric renovascular hypertension: A thirty-year experience of operative treatment

Purpose: This study was undertaken to characterize the changing operative treatment of pediatric renovascular hypertension and subsequent outcomes in a 30-year experience at a single institution.Methods: Clinical data were analyzed on 57 pediatric patients, 24 girls and 33 boys, ranging in age from 10 months to 17 years, who underwent operations for renovascular hypertension from 1963 to 1993 at the University of Michigan. Renal artery disease included atypical medial - perimedial dysplasia, often with secondary intimal fibroplasia (88%), and inflammatory mural fibrosis (12%). Abdominal aortic narrowings affected 15 patients. Data were categorized into three chronologic eras (I:1963 - 1972, II:1973 - 1980, and III:1981 - 1993) to allow identification of therapeutic trends.Results: Primary surgical procedures were undertaken 74 times. Ex vivo reconstruction was necessary once. Primary operations included aortorenal bypass with autogenous vein grafts (n = 26) or internal iliac artery grafts (n = 7); iliorenal bypass with vein grafts (n = 2); renal artery resection beyond the stenosis and reimplantation into the aorta (n = 10), the main renal artery (n = 2), an adjacent segmental renal artery (n = 3), or the superior mesenteric artery (n = 3); renal artery resection and reanastomosis (n = 3); focal renal arterioplasty (n = 2); operative dilation (n = 7); splenorenal bypass (n = 2); and primary nephrectomy (n = 7). Among 23 primary operations performed in era I, 56.5% were aortorenal bypasses with vein grafts, but in era III this form of revascularization represented only 3% of 33 primary operations. No reimplantations were performed in era I, whereas reimplantations accounted for 51.5% of era III procedures. Thirteen patients underwent staged or concomitant aortic reconstructions with thoracoabdominal aortoaortic bypass grafts (n = 5) or patch aortoplasty (n = 8). Fourteen patients underwent a total of 20 secondary operations, including seven secondary nephrectomies. Operative therapy benefited 98% of these children: hypertension was cured in 45 (79%), improved in 11 (19%), and unchanged in one (2%). There were no operative deaths.Conclusions: Contemporary surgical management emphasizes direct reimplantation of main renal arteries into the aorta, reimplantation of segmental arteries into adjacent renal arteries, patch aortoplasty for associated abdominal aortic coarctations, and single-stage revascularizations. Pediatric patients with renovascular hypertension clearly benefit from carefully executed operative therapy. (J VASC SURG 1995;21:212-27.)     

Chronic Renal Insufficiency and Risk of Early Mortality in Patients Undergoing Carotid Endarterectomy

We compared early outcome after carotid endarterectomy (CEA) in patients (n = 857 with 1,011 CEA interventions) with and without chronic renal insufficiency (CRI). Two groups were compared: a group with normal renal function (n = 909) and a group with CRI (creatinine ≥1.5 mg/dL and clearance of ≤30 mL/min, as well as dialysis and transplant patients, n = 102). Mean age was significantly higher in CRI patients (71.22 vs. 68.33 years, p = 0.001). The incidence of smokers was 53.9% in the non-CRI group vs. 39.2% in CRI patients (p = 0.005). Hypertension (88.2% vs. 75.1, p = 0.003) and cardiac disease (58.8% vs. 47.4%, p = 0.029) were more common in the CRI group. The perioperative mortality rate was significantly higher in CRI patients (3.9% vs. 1.0%, p = 0.013). Multivariate logistic regression analysis showed a significant association between CRI and 30-day death rate (odds ratio = 3.76, p = 0.032). In this series, CRI patients presented an increased mortality. The mortality risk may be related to the increased rates of preoperative hypertension and coronary disease and perioperative myocardial infarction. A more reserved attitude seems indicated in planning CEA for patients with renal dysfunction in combination with a history of coronary artery disease.     

Stroke in surgery of the arteriosclerotic descending thoracic aortic aneurysms: influence of cross-clamping technique of the aorta.

OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms.     

Pararenal aortic aneurysms: the future of open aortic aneurysm repair

PURPOSE: As endovascular stent graft repair of infrarenal abdominal aortic aneurysms (AAAs) becomes more common, an increasing proportion of patients who undergo open operation will have juxtarenal aneurysms (JR-AAAs), which necessitate suprarenal crossclamping, suprarenal aneurysms (SR-AAAs), which necessitate renal artery reconstruction, or aneurysms with associated renal artery occlusive disease (RAOD), which necessitate repair. To determine the current results of the standard operative treatment of these patterns of pararenal aortic aneurysms, we reviewed the outcome of 257 consecutive patients who underwent operation for JR-AAAs (n = 122), SR-AAAs (n = 58), or RAOD (n = 77). METHODS: The patients with SR-AAAs and RAOD were younger (67.5 +/- 8.8 years) than were the patients with JR-AAAs (70.5 +/- 8.3 years), and more patients with RAOD were women (43% vs 21% for JR-AAAs and SR-AAAs). The patient groups were similar in the frequency of coronary artery and pulmonary disease and in most risk factors for atherosclerosis, except hypertension, which was more common in the RAOD group. Significantly more patients with RAOD had reduced renal function before surgery (51% vs 23%). Supravisceral aortic crossclamping (above the superior mesenteric artery or the celiac artery) was needed more often in patients with SR-AAAs (52% vs 39% for RAOD and 17% for JR-AAAs). Seventeen patients (7%) had undergone a prior aortic reconstruction. The most common renal reconstruction for SR-AAA was reimplantation (n = 37; 64%) or bypass grafting (n = 12; 21%) and for RAOD was transaortic renal endarterectomy (n = 71; 92%). Mean AAA diameter was 6.7 +/- 2.1 cm and was larger in the JR-AAA (7.1 +/- 2.1 cm) and SR-AAA (6.9 +/- 2.1 cm) groups as compared with the RAOD group (5.9 +/- 1.7 cm). RESULTS: The overall mortality rate was 5.8% (n = 15) and was the same for all the groups. The mortality rate correlated (P <.05) with hematologic complications (bleeding) and postoperative visceral ischemia or infarction but not with aneurysm group or cardiac, pulmonary, or renal complications. Renal ischemia duration averaged 31.6 +/- 21.6 minutes and was longer in the SR-AAA group (43.6 +/- 38.9 minutes). Some postoperative renal function loss occurred in 104 patients (40.5%), of whom 18 (7.0%) required dialysis. At discharge or death, 24 patients (9.3%) still had no improvement in renal function and 11 of those patients (4.3%) remained on dialysis. Postoperative loss of renal function correlated (P <.05) with preoperative abnormal renal function and duration of renal ischemia but not with aneurysm type, crossclamp level, or type of renal reconstruction. CONCLUSION: These results showed that pararenal AAA repair can be performed safely and effectively. The outcomes for all three aneurysm types were similar, but there was an increased risk of loss of renal function when preoperative renal function was abnormal. These data provide a benchmark for expected treatment outcomes in patients with these patterns of pararenal aortic aneurysmal disease that currently can only be managed with open repair.