Daniel J. Char

Modeling Stroke Risk After Coronary Artery Bypass and Combined Coronary Artery Bypass and Carotid Endarterectomy

Background and Purpose— The goals of this study were to compare the ability of statewide and institutional models of stroke risk after coronary artery bypass (CAB) to predict institution-specific results and to examine the potential additive stroke risk of combined CAB and carotid endarterectomy (CEA) with these predictive models. Methods— An institution-specific model of stroke risk after CAB was developed from 1975 consecutive patients who underwent nonemergent CAB from 1994 to 1999 in whom severe carotid stenosis was excluded by preoperative duplex screening. Variables recorded in the New York State Cardiac Surgery Program database were analyzed. This model (model I) was compared with a published model (model II) derived from analysis of the same variables using New York statewide data from 1995. Predicted and observed stroke risks were compared. These formulas were applied to 154 consecutive combined CAB/CEA patients operated on between 1994 and 1999 to determine the predicted stroke risk from CAB alone and thereby deduce the maximal added risk imputed to CEA. Results— Risk factors common to both models included age, peripheral vascular disease, cardiopulmonary bypass time, and calcified aorta. Additional risk factors in model I also included left ventricular hypertrophy and hypertension. Risk factors exclusive to model II included diabetes, renal failure, smoking, and prior cerebrovascular disease. Our observed stroke rate for isolated CAB was 1.7% compared with a rate predicted with model II (statewide data) of 1.56%. The observed stroke rate for combined CEA/CAB was 3.9%. When the Stony Brook model (model I) based on patients without carotid stenosis was used, the predicted stroke rate was 2.8%. When the statewide model (model II), which included some patients with extracranial vascular disease, was used, the predicted stroke rate was 3.4%. The differences between observed and predicted stroke rates were not statistically significant. Conclusions— Estimation of stroke risk after CAB was similar whether statewide data or institution-specific data were used. The statewide model was applicable to institution-specific data collected over several years. Common risk factors included age, aortic calcification, and peripheral vascular disease. The observed differences in the predicted stroke rates between models I and II may be due to the fact that carotid stenosis was specifically excluded by duplex ultrasound from the patient population used to develop model I. Modeling stroke risk after CAB is possible. When these models were applied to patients undergoing combined CAB/CEA, no additional stroke risk could be ascribed to the addition of CEA. Such models may be used to identify groups at increased risk for stroke after both CAB and combined CAB/CEA. The ultimate place for CEA in patients undergoing CAB will be defined by prospective randomized trials.

Combined coronary artery bypass and carotid endarterectomy: long-term results.

PURPOSE We determined late survival, freedom from late stroke, and freedom from late cardiac events in patients treated by combined coronary artery bypass and carotid endarterectomy (CAB/CEA). METHODS All patients who underwent CAB/CEA in our institution between January 1994 and December 1999 were identified. Follow-up data were obtained from office records and telephone interviews. Endpoints included death from any cause, stroke, and non-fatal cardiac events (MI, CHF, percutaneous transluminal angioplasty with stenting, redo CAB). Data were expressed in life table format. RESULTS Over a 6-yr period 154 patients had combined CAB/CEA with a 3.9% postoperative stroke rate. Six patients (3.9%) died, leaving 148 patients for follow-up. Average follow-up was 38 +/- 23 months (range: 1-82 months). During the follow-up period two patients (1.4%) had late strokes and 17 patients (11%) had late non-fatal cardiac events. The late mortality rate was 13% (19 patients). Of the late mortalities, four were related to cardiac disease and one to stroke. Using Kaplan-Meier analysis, the 5-yr survival probability was 80 +/- 4.3%. The freedom from late ipsilateral neurologic events was 98 +/- 1.3% at 5 yr. The freedom from late cardiac events was 82 +/- 4.6% at 5 yr. CONCLUSIONS The large majority of patients with combined coronary and carotid artery disease can be expected to live for greater than 5 yr. Therefore, these patients should be considered candidates for prophylactic CEA for stroke prevention, even when their carotid lesions are asymptomatic. Successful CAB/CEA provides good long-term survival and freedom from late cardiac events, as well as excellent freedom from late stroke. Further reduction in perioperative events will make this operative approach even more attractive in patients with combined disease.

Surgical Intervention for Acute Intestinal lschemia: Experience in a Community Teaching Hospital

The aim of this study was to evaluate the current management of acute mesenteric ischemia secondary to thrombotic or embolic occlusion of visceral vessels in a community teaching hospital. Between October 1997 and July 2000, a review of all hospital discharges revealed 83 patients with a discharge diagnosis of “acute vascular insufficiency-intestine.” Among these 83 patients, 22 cases of acute mesenteric ischemia were confirmed. Management of these 22 patients was divided into 2 groups for analysis. In Group A, 14 patients were aggressively treated with visceral angiography (n = 10), visceral artery bypass (n = 8), visceral embolectomy (n = 4), and bowel resection (n = 7). In 8 of 14 of these patients, surgical intervention occurred in less than 24 hours from presentation. In Group B, 8 patients were managed with supportive care because of advanced age (mean age = 86 ±7 years), comorbid conditions, or patient and family preference. Postoperative morbidity in Group A consisted of cardiac events (n = 3), pulmonary insufficiency (n = 5), and prolonged gastrointestinal tract dysfunction (n = 3). Twelve of 14 patients in Group A survived and were discharged, whereas only 2 of 8 patients in Group B survived and were discharged from the hospital. Although the literature suggests that there can be a significant delay in the diagnosis and treatment of acute mesenteric ischemia, the early recognition and aggressive treatment of acute mesenteric ischemia resulted in a good survival rate. Supportive management of very elderly and debilitated patients needs to be considered on a case-by-case basis. Although the outlook for such patients is dismal, survivors are possible as demonstrated by this series.

Chronic mesenteric ischemia: diagnosis and treatment.

Chronic mesenteric ischemia is an uncommon manifestation of atherosclerotic disease. The presentation of chronic mesenteric ischemia is often confusing and the diagnosis is usually not made until late in the course of the disease. Selective angiography is considered the gold standard for establishing the diagnosis of chronic mesenteric ischemia. The treatment options for patients presenting with symptomatic chronic mesenteric ischemia include various surgical approaches to revascularization and catheter-based interventions.

Endovascular repair of an arteriovenous fistula from a ruptured hypogastric artery aneurysm--a case report.

A spontaneous ilioiliac arteriovenous fistula secondary to rupture of a hypogastric artery aneurysm is an unusual occurrence. A case of an endovascular repair of this challenging problem is reported.