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N R Hertzer

Publications and source records attributed to N R Hertzer.

At least 37 records · Page 2Linked to original sources
PubMed1997

Early outcome assessment for 2228 consecutive carotid endarterectomy procedures: the Cleveland Clinic experience from 1989 to 1995.

PURPOSE: Several randomized trials now have established guidelines regarding patient selection for carotid endarterectomy (CEA) that have been widely accepted but have little relevance unless they are considered in the context of perioperative risk. The purpose of this study was to demonstrate the feasibility of early outcome assessment using a computerized database. METHODS: Since 1989 demographic information and in-hospital results for all surgical procedures performed by the members of our department have been entered into a prospective registry. For the purpose of this report, we have analyzed the stroke and mortality rates for 2228 consecutive CEAs (2046 patients), including 1924 that were performed as isolated operations and 304 that were combined with simultaneous coronary artery bypass grafting (CABG). This series incidentally contains a total of 153 reoperations for recurrent carotid stenosis. RESULTS: The respective stroke and mortality rates were 0.5% and 1.8% for all isolated CEAs, 4.3% and 5.3% for all CEA-CABG procedures, and 4.6% and 2.0% for carotid reoperations. According to a multivariable statistical model, the composite stroke and mortality rate for isolated CEA was significantly influenced by female gender (p = 0.050), by the urgency of intervention (p = 0.026), and by carotid reoperations (p = 0.024). Gender (p = 0.030) and urgency (p = 0.040) also were associated with differences in the stroke rate alone; furthermore, the incidence of perioperative stroke was higher in conjunction with synthetic patching (odds ratio, 2.6; 95% confidence interval, 1.2 to 5.3) and was marginally higher with primary arteriotomy closure (odds ratio, 2.7; 95% confidence interval, 0.8 to 9.5) compared with vein patch angioplasty (1.3%). The method used to repair the arteriotomy was the only independent factor that qualified for the multivariable composite stroke and mortality models that were applied to the combined CEA-CABG procedures, but too few patients in this cohort had synthetic patches or primary closure to validate the perceived superiority of vein patching. CONCLUSIONS: Prospective outcome assessment is essential to reconcile the indications for CEA with its actual results, and it may lead incidentally to important observations concerning patient care.

Adult↗
PubMed1997

Carotid endarterectomy in adults 50 years of age and younger: a retrospective comparative study.

PURPOSE: Atherosclerotic carotid artery stenosis (CAS) is the most common cause of stroke in young adults. We retrospectively studied clinical characteristics of premature CAS and the safety and durability of carotid endarterectomy (CEA) in 56 patients 50 years of age or younger (mean, 46.4 years; 34 (60%) males; group I) who underwent primary CEA at the Cleveland Clinic between 1983 and 1993. METHODS: The patients were identified from the Vascular Surgery Registry and were compared with 202 randomly selected patients 60 years of age and older (mean, 69.3 years; group II) who were frequency-matched by gender and the year of primary CEA. Carotid shunting was used routinely, and the arteriotomy was patched in the majority of cases. Patients were followed-up for mean of 47.2 months (group I) and 46.0 months (group II). RESULTS: No significant differences were found in the indications for CEA (symptomatic CAS, 49% in group I vs 48% in group II) or the prevalence of diabetes, coronary diseases, and lower extremity arterial disease. Younger adults were more likely to have a history of smoking (93% vs 76%; p = 0.005), hypertension (71% vs 52%; p = 0.006), premature menopause (57% vs 18%; p < 0.001) and had lower levels of high-density lipoprotein cholesterol (p = 0.03). There were no in-hospital deaths. Perioperative strokes in the distribution of the operated artery occurred within 24 hours in one younger patient (1.8%) and in one older patient (0.5%). This was attributed to early carotid thrombosis in the young patient. Major late postoperative neurologic complications were documented in one young patient (1.8%) and six older patients (3%). Patients in group I were at significantly higher risk for recurrent carotid stenosis (risk ratio, 3.1; 95% confidence interval [CI], 1.3 to 7.3; p = 0.010); younger individuals remained at significantly higher risk for recurrent stenosis even after adjusting for smoking and hypertension (risk ratio, 3.7; 95% CI, 1.5 to 9.4; p = 0.006). By life-table analysis, younger adults tended to have a higher rate of late reoperations (p = 0.065). CONCLUSIONS: CEA can be safely performed in young adults with premature CAS, although younger individuals appear to have higher rates of recurrent carotid stenosis compared with older counterparts.

Adult↗
PubMed1996

Concordance of preoperative clinical risk with angiographic severity of coronary artery disease in patients undergoing vascular surgery.

BACKGROUND: Preoperative clinical indexes to stratify cardiac risk have not been validated angiographically. Our aims were to determine the concordance of clinical risk with severity of coronary stenosis and to develop and validate a preoperative clinical index to exclude the presence of significant coronary stenosis. METHODS AND RESULTS: We carried out a prospective study of 878 consecutive patients (including the derivation and validation sets). "Severe" stenosis was defined as three-vessel (> or = 50% stenosis in each), two-vessel (> or = 50% stenosis in one when the other is > or = 70% stenosis of the left anterior descending), or left main disease (> or = 50%); "critical" stenosis was three-vessel (> or = 70% stenosis in each) and/or left main stenosis > or = 70%. A preoperative clinical index (diabetes mellitus, prior myocardial infarction, angina, age > 70 years, congestive heart failure) was used to stratify patients. A gradient of risk for severe stenosis was seen with increasing numbers of clinical markers. The following prediction rules were developed: The absence of severe coronary stenoses can be predicted with a positive predictive value of 96% for patients who have no (1) history of diabetes, (2) prior angina, (3) previous myocardial infarction, or (4) history of congestive heart failure. The absence of critical coronary stenoses can be predicted with a positive predictive value of 94% for those who have no (1) prior angina, (2) previous myocardial infarction, or (3) history of congestive heart failure. CONCLUSIONS: By reliably identifying a large proportion of patients with a low likelihood of significant stenoses, these prediction rules can help to substantially reduce healthcare costs associated with preoperative cardiac risk assessment for noncardiac surgery.

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PubMed1996

Angiographic correlates of cardiac death and myocardial infarction complicating major nonthoracic vascular surgery.

In a case-control study of 63 patients undergoing major nonthoracic vascular surgery with prior cardiac catheterization, we found total coronary occlusion serving viable myocardium and "nonobstructive" lesions to be the most common proximate cause of perioperative myocardial infarction or death. The extent of coronary disease by several measures was significantly correlated with adverse outcome, and prior bypass surgery appeared to be protective.

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PubMed1996

Vascular surgery in the United States: workforce issues. Report of the Society for Vascular Surgery and the International Society for Cardiovascular Surgery, North American Chapter, Committee on Workforce Issues.

The Committee on Workforce Issues of the Society for Vascular Surgery (SVS) and the North American Chapter, International Society for Cardiovascular Surgery (NA-ISCVS) generated data on the numbers and trends of operations performed and workforce requirements to provide surgical care of patients with vascular disease. Data for analysis were obtained from The National Center for Health Statistics-National Hospital Discharge Survey and questionnaires sent to 2732 vascular surgeons. The data showed that SVS/NA-ISCVS and regional vascular society (RVS) surgeons performed 51% of 583,000 vascular procedures undertaken in the United States in 1992. This represents a 24% increase over the 41% reported in 1985 by similarly defined surgeons. Analysis of 1992 index cases documented that SVS/NA-ISCVS and RVS surgeons accounted for 80% of 31,000 aortoiliofemoral bypasses, 68% of 46,000 aortic aneurysmectomies, 64% of 91,000 carotid endarterectomies, and 72% of 98,000 angioaccess procedures. The mean numbers of vascular operations performed in 1992 by SVS/NA-ISCVS and RVS surgeons were 144 and 100, respectively. These procedures represented 64% and 39% of the total surgical caseload of SVS/NA-ISCVS and RVS surgeons, respectively. American Board of Surgery (ABS)-certified vascular surgeons performed a mean of 171 vascular operations in 1992. Other surgeons, including ABS-certified general surgeons, appear to be performing fewer vascular operations. The latter fact and the increasing incidence of vascular disease in an expanding elderly population supports a continued need for vascular surgery specialists. Evolving technology and new health care delivery systems, however, may lessen the need for surgical care of these patients. Continued assessments of workforce activity will allow better definition of changing vascular surgery needs.

Humans↗
PubMed1996

Influence of gender on cardiac risk and survival in patients with infrarenal aortic aneurysms.

PURPOSE: To determine whether gender distinction influence the cardiac risk or survival rates associated with surgical treatment of infrarenal abdominal aortic aneurysms (AAAs). METHODS: From 1983 to 1988, graft replacement of intact AAAs was performed in 490 men (84%) and in 92 women (16%) who had no history of myocardial revascularization before the discovery of their AAAs. Patients of both genders were comparable with respect to mean age (68 years) and the prevalence of coronary artery disease (CAD) by standard clinical criteria (men, 73%; women, 65%). Preoperative coronary angiography was obtained in 471 of the 582 patients (men, 81%; women, 80%) during this particular study period. Preliminary coronary bypass was warranted on the basis of existing indications in 111 (24%) of these 471 patients (men, 25%; women, 18%), including 104 (31%) of the 337 who had clinical indications of CAD (men, 32%; women, 26%) but only 7 (5.2%) of the 134 who did not (men, 6%; women, 4%). Follow-up data were collected during a mean interval of 53 months (men, 54 months; women, 48 months) and were analyzed by Kaplan-Meier survival analysis and Cox proportional hazards models. RESULTS: Twenty-nine perioperative deaths (5.0%) occurred in conjunction with AAA repair (men, 5.1%; women, 4.3%), and 126 early and late deaths have occurred (men, 22%; women, 22%). Survival rates for the series were found to correlate with age (p < 0.001), the serum creatinine level (p < 0.001), and the coronary angiographic classification (p < 0.001). No significant differences were identified between the gender cohorts. The cardiac mortality rate for AAA resection was only 1.8% in the 111 patients who had preliminary coronary bypass, but five additional perioperative deaths (4.5%) related to renal failure or sepsis occurred in this group. However, 5-year survival rates for patients receiving preliminary bypass (men, 82%; women, 75%) were closely comparable with those for patients found to have only mild to moderate CAD by angiography (men, 86%; women, 82%). CONCLUSION: We conclude that men and women with AAAs have similar cardiac risks and survival rates associated with surgical treatment. Our results also illustrate that the potential benefit of coronary intervention for severe CAD in patients of either gender must be considered in the context of long-term outcome and the early mortality rate of AAA repair.

Aged↗
PubMed1995

Surgical management of infected PTFE hemodialysis grafts: analysis of a 15-year experience.

The records of 52 consecutive patients who underwent surgical treatment for 57 episodes of hemodialysis graft infection (HGI) from 1977 to 1993 were reviewed to determine the mortality and morbidity associated with this complication and to clarify guidelines for its management. The study group consisted of 35 women and 17 men whose mean age was 57 years at initial graft placement. Thirty-three (58%) HGIs involved straight grafts in the upper arm, 12 (21%) straight forearm grafts, 11 (19%) loop forearm grafts, and 1 (2%) a loop groin fistula. All of these grafts were constructed with polytetrafluoroethylene (PTFE). All 57 cases of HGI showed at least local evidence and 41 (72%) caused systemic symptoms. Thirty-seven (65%) HGIs were associated with positive blood cultures. The predominant infecting organism was Staphylococcus, which was isolated alone or in combination with other organisms from 40 (70%) graft or would sites. Seventy-eight percent (31/40) of the staphylococcal infections involved Staphylococcus aureus. The median time from graft implantation to diagnosis of HGI was 7 months (mean 16 months, range 0 to 77 months) and from diagnosis to surgical treatment, 4 days (mean 6 days, range 0 to 26 days). Initial surgical management consisted of complete excision of all prosthetic material in 43 (75%) cases and partial excision in 14. The 30-day mortality rate following the last operation for the treatment of HGI was 12% (6/52) and was not significantly increased by incomplete excision. Six (86%) of the early deaths were related to sepsis and each of these patients had positive blood cultures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Surgical management of infrainguinal arterial prosthetic graft infections: review of a thirty-five-year experience.

PURPOSE: The purpose was to determine the early and late mortality and morbidity rates associated with infrainguinal arterial prosthetic graft infection (IAPGI) and to identify optimal methods of management. METHODS: The study included 53 men and 14 women (mean age, 61 years) in whom a total of 68 IAPGIs developed in the years 1959 to 1993. IAPGI involved 58 femoropopliteal grafts (85%), six femorodistal grafts (9%), and four other grafts or synthetic patches (6%). Graft material was dacron in 36 (53%), polytetrafluoroethylene in 28 (41%), and human umbilical vein in four (6%). Sixteen IAPGIs (24%) involved limbs that had required amputations before IAPGI was diagnosed. Twenty-six (38%) of the 68 grafts were thrombosed, and 14 (88%) of the 16 amputees had occluded grafts. RESULTS: Staphylococcal organisms were isolated from 34 (58%) of the 59 IAPGIs for which culture data were available. The median intervals until IAPGI was diagnosed were 3 months after implantation and 1 month after the last procedure involving the original graft. Initial management consisted of local measures only in 13 (19%), partial removal or in situ graft replacement in 15 (22%), and total graft excision in 40 (59%). Total excision was performed in 15 (94%) of the 16 patients with prior amputations and in only 25 (48%) of the 52 intact limbs. The overall postoperative mortality rate was 18%; seven (58%) of the 12 early deaths were related to sepsis, and all 12 occurred within the group of 51 patients (24%) for whom limb salvage was still being attempted (p = 0.056). IAPGI ultimately led to amputations in 21 (40%) of 52 intact limbs within the first year. Twenty-three (82%) of the 28 IAPGIs managed with incomplete graft removal required subsequent operations for continued sepsis, compared with five (13%) of the 40 treated with complete excision (p < 0.001). The cumulative 5-year survival rate (77%) for 53 patients who survived operation was less than that (89%) for the normal, age-matched U.S. male population. CONCLUSIONS: IAPGI is associated with substantial early mortality and amputation rates. Complete excision of infected graft material results in a significant reduction in the incidence of recurrent sepsis.

Adult↗
PubMed1995

Ten-year experience with abdominal aortic aneurysm repair in octogenarians: early results and late outcome.

PURPOSE: This study was undertaken to determine the mortality and morbidity rates associated with abdominal aortic aneurysm (AAA) repair in octogenarians and to identify factors that may influence survival in this age group. METHODS: One hundred fourteen patients (mean age 83 years) were admitted consecutively with 106 infrarenal and eight juxtarenal AAAs from 1984 through 1993. Ninety-four AAAs were asymptomatic, whereas 20 patients with symptoms had 11 intact and nine ruptured AAAs. The mean AAA diameter was 6.7 cm. Repair consisted of aortic bifurcation grafts in 77 patients (67%), tube grafts in 35 (31%), and extraanatomic procedures in 2 (2%). A total of 29 patients (25%) had undergone previous coronary artery bypass (24 patients) or transluminal coronary angioplasty (five patients) either incidentally or as a preliminary procedure before resection of their AAAs. RESULTS: The 30-day mortality rate for the entire series was 14%, but it declined from 23% (11/48) during the first 5 years to 8% (5/66) during the second 5 years of the study period (p = 0.028). Fatal complications occurred in nine (9.6%) of the 94 patients with asymptomatic AAAs and in seven (35%) of the 20 patients who had symptomatic AAAs (p = 0.008). Considering only patients with asymptomatic AAAs, the early mortality rate in the second 5 years (4%) improved significantly (p = 0.038) in comparison to that (17%) for the first 5 years of the study period. The cumulative 5-year survival rate of 48% for 97 available operative survivors was not quite so good as that (59%) for the normal male population of the United States at the age of 80 years (p < 0.0001). Nevertheless, the 5-year survival rate was 80% for 27 operative survivors who received previous myocardial revascularization compared with 38% for 70 others who did not (p = 0.0077). Multiple Cox-regression analysis identified the perioperative homologous blood requirement (p = 0.03) and a history of previous myocardial revascularization (p = 0.03) as significant independent factors influencing late survival. CONCLUSIONS: Repair of AAAs in properly selected octogenarians is safe and durable. When otherwise indicated, it should not be withheld on the basis of advanced age alone. Prior treatment of severe coronary artery disease is associated with enhanced late survival, but patient selection probably is an important consideration in this respect.

Aged↗
PubMed1994

Autogenous vein grafts for femorofemoral revascularization in contaminated or infected fields.

PURPOSE: The purpose of this study was to determine the indications and the long-term results for femorofemoral revascularization with autogenous vein grafts (AVG) rather than conventional synthetic materials. METHODS: A consecutive series of 13 men and 12 women (mean age 64 years) receiving femorofemoral AVG was collected during a retrospective review of our experience from 1979 to 1992. Sixteen of these 25 patients required revascularization for acute ischemia in the presence of potential groin contamination (group 1), and the remaining nine had frank infections involving previous synthetic grafts (group 2). New grafts were constructed with the greater saphenous vein in 23 patients (92%) and with the cephalic vein in two. RESULTS: One patient in each group (8%) died after operation with patent grafts. Preoperative and postoperative ankle/brachial indexes (ABI) were available for 12 patients in group 1 and for seven patients in group 2. There was significant improvement in the ABI among 11 patients with ischemia in group 1 (mean 0.33 +/- 0.13; p = 0.0001), whereas no change in the ABI occurred in conjunction with the replacement of patent infected grafts among six patients in group 2 (mean 0.04 +/- 0.17; p = NS). One patient from each group sustained a reduction in postoperative ABI for the recipient limb despite a patent AVG. Cumulative 3-year survival and primary patency estimates for all 23 operative survivors were 63% and 75%, respectively. Late results seemed to be comparable in group 1 and group 2, but each contained too few patients for adequate analysis. CONCLUSIONS: Despite their infrequent use, AVG seem to represent a reasonable alternative to synthetic bypass for femorofemoral revascularization in patients having either contaminated wounds or established graft infections.

Adult↗
PubMed1994

Ultrasound-guided compression repair of postcatheterization pseudoaneurysms: results of treatment in one hundred cases.

PURPOSE: The purpose of this report is to describe the indications, technique, and results for ultrasound-guided compression repair (UGCR) of postcatheterization pseudoaneurysms at a large medical center in which catheter-based diagnostic and interventional procedures are frequently used. METHODS: We reviewed the initial series of 100 consecutive patients who underwent UGCR in our noninvasive vascular laboratory from May 1991 through August 1992. Nearly all (n = 95) of these pseudoaneurysms involved the common femoral artery or its major branches, and each was manually compressed with a 5 MHz linear transducer for 10-minute intervals until the pseudoaneurysm was completely occluded or the procedure was considered to be a failure. RESULTS: UCGR was immediately successful in 94 patients, including 30 (86%) of 35 patients who were receiving anticoagulants and 64 (98%) of the 65 who were not (p = 0.019). The average compression time to achieve occlusion was 33 minutes (range 10 to 120 minutes), but was nearly twice as long (51 minutes) for pseudoaneurysms that had been present for more than 14 days. There were no related complications, but recurrent pseudoaneurysms occurred in six (20%) of 30 patients who continued to receive formal anticoagulation, compared with only four (6%) of 64 who did not (p = 0.074). Eight of the 10 recurrences were discovered within 24 hours after primary UGCR, but two others presented at 16 and 35 days, respectively. Eight recurrent lesions were corrected by repeat UGCR, whereas the remaining two required surgical repair. CONCLUSIONS: UGCR provides a reliable alternative to surgical treatment for postcatheterization pseudoaneurysms. Adequate follow-up is important, however, especially in patients for whom continued anticoagulation is necessary.

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