Isolated high lactate or low central venous oxygen saturation after cardiac surgery and association with outcome.

OBJECTIVE: To determine if isolated abnormally low central venous oxygen saturation (ScvO2) or elevated lactate levels on admission to an intensive care unit (ICU) are associated with increased morbidity and length of stay (LOS) after cardiac surgery. DESIGN: Retrospective, observational. SETTING: Academic tertiary care hospital. PARTICIPANTS: Six hundred twenty-nine adult, on-pump cardiac surgery patients with ScvO2 and arterial lactate obtained on admission to the ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Comparing outcomes across the isolated low ScvO2 and high lactate categories, no significant differences in ICU/hospital LOS, ICU readmission rate, length of mechanical ventilation, or incidence of major complications were observed in patients with ScvO2<70% and lactate < 2 mmol/L or in those with lactate 2-3.9 mmol/L and ScvO2 ≥ 70%. However, patients with lactate ≥ 4 mmol/L and ScvO2 ≥ 70% exhibited significantly longer median ICU LOS (p = 0.018), hospital LOS (p = 0.032), length of mechanical ventilation (p = 0.0001), and higher incidence of major complications (p = 0.008). Multivariate analysis identified isolated elevated lactate levels ≥ 4 mmol/L as an independent predictor for major complications (OR 4.29, p = 0.0008). CONCLUSIONS: Low ScvO2 with normal lactate or moderately elevated lactate with normal ScvO2 upon ICU admission after cardiac surgery was not associated with increased morbidity or length of stay. Markedly elevated lactate levels in the setting of a normal ScvO2 was associated with significantly higher incidence of major complications and prolonged length of stay. Additionally, a lactate level ≥ 4 mmol/L was an independent predictor of major complications.

Predicting early death after cardiovascular surgery by using the Texas Heart Institute Risk Scoring Technique (THIRST).

Preoperative risk-prediction models are an important tool in contemporary surgical practice. We developed a risk-scoring technique for predicting in-hospital death for cardiovascular surgery patients. From our institutional database, we obtained data on 21,120 patients admitted from 1995 through 2007. The outcome of interest was early death (in-hospital or within 30 days of surgery). To identify mortality predictors, multivariate logistic regression was performed on data from 14,030 patients from 1995 through 2002 and risk scores were computed to stratify patients (low-, medium-, and high-risk). A recalibrated model was then created from the original risk scores and validated on data from 7,090 patients from 2003 through 2007. Significant predictors of death included urgent surgery within 48 hours of admission, advanced age, renal insufficiency, repeat coronary artery bypass grafting, repeat aortic aneurysm repair, concomitant aortic aneurysm or left ventricular aneurysm repair with coronary bypass or valvular surgery, and preoperative intra-aortic balloon pump support. Because the original model overpredicted death for operations performed from 2003 through 2007, this was adjusted for by applying the recalibrated model. Applying the recalibrated model to the validation set revealed predicted mortality rates of 1.7%, 4.2%, and 13.4% and observed rates of 1.1%, 5.1%, and 13%, respectively. Because our model discriminates risk groups by using preoperative clinical criteria alone, it can be a useful bedside tool for identifying patients at greater risk of early death after cardiovascular surgery, thereby facilitating clinical decision-making. The model can be recalibrated for use in other types of patient populations.

Heart failure due to a post-traumatic calcified pericardial hematoma.

Chest-wall trauma can produce bleeding into the pericardium and initiate a process of inflammation, calcification, and scarring that may eventually produce pericardial constriction. Herein, we present an unusual case of a man who experienced chest trauma at age 16 years, and developed heart failure 40 years later secondary to a large, calcified pericardial hematoma. During its prolonged genesis, the pericardial mass became deeply embedded in the myocardium and produced evidence of both constrictive and restrictive cardiomyopathy. Despite attempted surgical resection, the lesion could not be completely removed, nor could its hemodynamic impact be completely resolved.

Outcomes and risk factors in 1,609 carotid endarterectomies.

Severe carotid stenosis is typically treated with carotid endarterectomy (CEA), but there is debate about the safety of this procedure in patients with occlusion of the contralateral artery, previous CEA in the same artery, and other risk factors. To evaluate the association of these factors with outcomes in standard CEA with Dacron patch angioplasty, we examined the records of 1,609 consecutive isolated CEAs performed at our institution over a 10-year period on 1,400 patients (851 men and 549 women; mean age, 69.5 yr) with symptomatic or high-grade asymptomatic carotid lesions. Twenty-three patients (1.4%) had perioperative strokes, of which 2 were fatal. The overall same-admission mortality was 0.2% (4 patients). Same-admission stroke/death was more likely in patients with any history of tobacco use (odds ratio [OR], 4.6; 95% confidence interval [CI], 1.6-13.6), contralat-eral occlusion (OR, 3.3; 95% CI, 1.2-9.1), angina with a Canadian Cardiovascular Society classification of 2 or greater (OR, 3.2; 95% CI, 1.4-7.6), or transient ischemic attack within the 6 weeks before surgery (OR, 2.4; 95% CI, 1.05-5.3). A total of 9 patients (0.6%) died within 30 days of CEA; our multivariate analysis did not reveal any significant predictors of 30-day mortality. We conclude that standard CEA with patch angioplasty is associated with low rates of death and morbidity for most patients, but patients with any history of tobacco use, substantial angina, contralateral occlusion, or preoperative transient ischemic attack may have an elevated risk of adverse outcomes.

Prosthesis-patient mismatch affects long-term survival after mechanical valve replacement.

OBJECTIVE: We sought to examine the relationship between the degree of prosthesis-patient mismatch and long-term survival after mechanical aortic valve replacement. METHODS: Prospectively collected long-term follow-up data from 469 consecutive patients who underwent aortic valve replacement between 1995 and 1998 were reviewed. The indexed effective orifice area was derived from the reference normal values of effective orifice area divided by the patient's body surface area. Outcome was stratified according to the severity of prosthesis-patient mismatch: moderate mismatch was defined as 0.65 to 0.85 cm(2)/m(2) and severe mismatch as less than 0.65 cm(2)/m(2). The Cox proportional-hazards model with propensity score adjustment was used to adjust for the observed differences in baseline characteristics between the mismatch groups. RESULTS: The degree of prosthesis-patient mismatch was minimal in 57% of patients, moderate in 39%, and severe in 4%. Predictors of clinically significant mismatch included small aortic valve sizes (19 and 21 mm), obesity, age greater than 65 years, and class III or IV heart failure. During a median follow-up period of approximately 7.9 years, overall survival was 77% in patients with minimal mismatch, 63% in those with moderate mismatch, and only 47% in those with severe mismatch (P < .001). Moderate or severe mismatch was a significant predictor of poorer survival (hazard ratio, 1.6; 95% confidence interval, 1.4-2.3; P < .01), even after adjustment for all significant clinical predictors (ie, propensity score; hazard ratio, 1.2; 95% confidence interval, 1.0-1.5; P = .05). CONCLUSIONS: In a large aortic valve surgery population, prosthesis-patient mismatch occurred in 43% of patients, and those with significant mismatch had worse long-term outcomes than those with minimal mismatch.

C-ring mitral annuloplasty: 27-year follow-up.

We report the long-term follow-up of a patient with rheumatic mitral valve disease who underwent annuloplasty with a specially developed C-ring (the Cooley C-ring) for mitral valve repair in 1977. The repaired valve remained competent and unobstructed for 27 years before requiring replacement.

Combined endovascular and surgical treatment of infected carotid-carotid bypass graft.

PURPOSE: To present a complex case involving an infected carotid-carotid bypass graft that was successfully treated with a stent-graft and subsequent surgical removal of the infected graft. CASE REPORT: A 75-year-old woman presented with persistent purulent drainage of an infected and exposed carotid-carotid prosthetic bypass graft. Wound cultures revealed methicillin-resistant Staphylococcus aureus. She was treated with appropriate intravenous antibiotic therapy without improvement in wound drainage. Because of her comorbid conditions, a decision was made to pursue endovascular revascularization of her left and right common carotid arteries (CCA), with subsequent surgical removal of the infected prosthetic graft. The patient underwent balloon angioplasty; a 7x18-mm Omnilink stent was deployed in the innominate artery and a 7x18-mm Herculink stent in the ostial left CCA. During the same procedure, the carotid-carotid bypass graft was excluded with deployment of an 8x50-mm Viabahn stent-graft in the right CCA. Several days later, the infected and now thrombosed carotid-carotid bypass graft was surgically removed, and an area of adjacent muscle was used to patch the previously excluded connection of the bypass from the right CCA. A saphenous vein patch was used to repair the defect in the left CCA. Her postoperative course was uneventful. At 1 year, the clinical and duplex examinations revealed satisfactory wound healing and patent left and right CCAs. CONCLUSION: This case indicates that a combined endovascular and surgical approach may be a safe and effective option in the treatment of carotid-carotid bypass graft infection.

Myocardial thievery: the coronary-subclavian steal syndrome.

Coronary-subclavian steal syndrome entails the reversal of blood flow in a previously constructed internal mammary artery coronary conduit, which produces myocardial ischemia. The most frequent cause of the syndrome is atherosclerotic disease in the ipsilateral, proximal subclavian artery. Although coronary-subclavian steal was initially reported to be rare, the increasing documentation of this phenomenon and its potentially catastrophic consequences in recent series suggests that the incidence of the problem has been underreported and that its clinical impact has been underestimated. We review the causes and background of coronary-subclavian steal; methods of preventing, diagnosing, and treating it; and the potential influence of various treatment regimens on long-term survival and the likelihood of late adverse events in patients with coronary-subclavian steal syndrome.

Concomitant brachiocephalic and coronary artery disease: outcome and decision analysis.

BACKGROUND: In patients with coronary artery disease, concomitant brachiocephalic disease may affect outcome and influence decision making regarding operative staging, technique, and choice of conduit. METHODS: Eighty consecutive patients (mean age, 59.3 years; 60.0% male) with concomitant brachiocephalic and coronary artery disease were identified either before (group A, n = 48) or after (group B, n = 32) coronary artery bypass grafting. Patients who had symptomatic brachiocephalic and coronary artery disease before surgery underwent concomitant brachiocephalic reconstruction and coronary artery bypass grafting using either all-vein coronary conduits (n = 41) or vein-and-internal mammary artery conduits (n = 7). Patients who had coronary-subclavian steal syndrome after coronary artery bypass (group B, n = 32) underwent either surgical (n = 5) or endovascular (n = 27) brachiocephalic reconstruction only. RESULTS: All patients were asymptomatic after intervention. Operative mortality was 4.2% for group A and 3.1% for group B. The perioperative stroke rate was 2.1% for group A and 0% for group B. Actuarial 10-year freedom from specific events for group A was as follows: death 59.9 +/- 12.8%, brachiocephalic restenosis 100%, coronary-subclavian steal syndrome 100%, myocardial infarction 83.5 +/- 10.5%, stroke 82.1 +/- 9.9%, redo coronary artery bypass grafting 95.8 +/- 4.1%, other vascular operation 82.2 +/- 8.9%, and adverse cardiac outcome (death, redo coronary artery bypass grafting, or myocardial infarction) 52.9% +/- 13.2% (for patients with all-vein conduits) or 100% (for patients with vein-and-internal mammary artery conduits). At midterm follow-up (mean, 2.92 years), both the surgical and the endovascular treatment subgroups of group B had 100% brachiocephalic patency. CONCLUSIONS: Long-term results in a limited population support continued evaluation of concomitant brachiocephalic reconstruction and coronary artery bypass grafting with use of the internal mammary artery conduit in an attempt to improve late survival in patients with concomitant disease. The excellent midterm brachiocephalic patency after either surgical or endovascular treatment of patients with coronary-subclavian steal syndrome supports continued evaluation of both methods.

Brachiocephalic reconstruction I: operative and long-term results for complex disease.

OBJECTIVES: Complex brachiocephalic disease involves multiple vessels and is frequently associated with multisystem atherosclerosis. We reviewed surgical outcome and examined the impact of this problem on decision making regarding operative staging, technique, and choice of conduit. METHODS: Between 1966 and 2000, 157 consecutive patients (mean age, 54.0 years; 48.4% male) with innominate artery or multivessel brachiocephalic disease underwent operative reconstruction using either a transthoracic approach (group A, n = 113) or a less invasive, extrathoracic approach (group B, n = 44). Reconstruction required multiple distal anastomoses in 70 patients (44.6%), concomitant coronary artery bypass grafting (CABG) in 37 patients (23.6%), and concomitant carotid endarterectomy (CEA) in 26 patients (16.6%). RESULTS: No significant differences were found between group A and group B when operative mortality (2.7% vs 2.3%) and stroke rates (2.7% vs 6.8%) were analyzed. However, 10 years after surgery, freedom from graft failure was significantly better in group A (94.4% +/- 4.4%) than in group B (60.3% +/- 13.4%) ( P = .002). Freedom from graft failure was adversely affected by nonaortic inflow ( P = .002) and axillo-axillary cervical grafts ( P = .0001). Mortality and stroke rates for subgroups having multiple distal anastomoses (2.9%, 2/70 and 4.3%, 3/70), concomitant CABG (5.4%, 2/37 and 0, 0/37), and concomitant CEA (3.8%, 1/26 and 3.8%, 1/26) were similar to those of other patients. For the entire patient group, 10-year rates of actuarial freedom from specific events were death, 68.8% +/- 6.0%; myocardial infarction, 86.7% +/- 4.5%; stroke, 87.0% +/- 4.4%; coronary revascularization, 88.0% +/- 3.6%, and other vascular operation, 79.9% +/- 4.4%. CONCLUSIONS: Transthoracic arch reconstruction for complex brachiocephalic disease can be done with acceptably low morbidity and mortality similar to those of a less invasive, extrathoracic approach. Furthermore, the transthoracic approach is associated with significantly better long-term freedom from graft failure, possibly because it preserves aortic inflow to the great vessels. Nonetheless, the high frequency of late events in this relatively young patient population reflects the presence of multisystem atherosclerosis and suggests the need for close follow-up and lifestyle modification.

Brachiocephalic reconstruction II: operative and endovascular management of single-vessel disease.

OBJECTIVE: Although the surgical management of brachiocephalic disease is well established, evolving endovascular techniques present new options for treatment. We explored the potential benefits and drawbacks of these interventions in terms of outcome. METHODS: From 1966 to 2004, 391 consecutive patients (43.7% male; mean age, 61.9 years) with single-vessel brachiocephalic disease were treated with either operative bypass (group A; n = 229) or percutaneous transluminal angioplasty and stenting (group B; n = 162). RESULTS: All patients were asymptomatic after surgery or endovascular intervention. Group A and group B had similar operative mortality (0.9% vs 0.6%) and stroke (1.3% vs 0%) rates. However, 5 years after the procedure, group A had significantly better freedom from graft or intervention failure (92.7% +/- 2.1%) than did group B (83.9% +/- 3.7%; P = .03, Kaplan-Meier analysis; P = .001, Cox regression analysis). At 10 years, group A had the following rates of actuarial freedom from specific events: death, 73.7% +/- 4.6%; myocardial infarction, 84.2% +/- 3.6%; stroke, 91.4% +/- 3.4%; graft failure, 88.1% +/- 3.3%; coronary revascularization, 69.8% +/- 5.1%; and other vascular operation, 70.7% +/- 4.6%. Endovascular intervention involved less initial cost (mean savings, $8787 per procedure), was less invasive, and did not necessitate general anesthesia. On satisfaction questionnaires, 96.5% of patients receiving an endovascular intervention and 95.1% of patients receiving operative bypass for single-vessel brachiocephalic disease subjectively rated their treatment as "good" or "very good." CONCLUSIONS: Operative bypass and endovascular intervention for single-vessel brachiocephalic disease are both associated with acceptably low operative morbidity and mortality. Operative bypass produces significantly better mid-term freedom from graft or intervention failure than endovascular intervention and produces excellent long-term freedom from failure. Endovascular intervention offers tangible benefits regarding cost, level of invasiveness, and subjective patient satisfaction. Undetermined are the differences between the procedures regarding long-term durability, patterns of failure, efficacy as an adjunct to coronary artery bypass grafting, need for anticoagulation, efficacy as treatment for complex (multivessel) disease, and long-term cost.

Iatrogenic left subclavian artery-to-left brachiocephalic vein fistula: successful repair without a sternotomy.

Subclavian vein catheterization can result in arteriovenous fistula formation--a rare complication that will eventually lead to heart failure if left untreated. The world medical literature describes several subclavian artery-to-subclavian vein fistulas and 2 subclavian artery-to-brachiocephalic vein fistulas, both on the right side. To our knowledge, there have been no reports of an iatrogenic left subclavian artery-to-left brachiocephalic vein fistula. We report a case in which this complication occurred after unsuccessful transvenous pacemaker placement. We treated the fistula with a simple surgical technique that avoided the need for a sternotomy. Although stenting is typically the procedure of choice for such fistulas, our technique is useful when stenting is not indicated.

Surgical treatment of coronary artery anomalies: report of a 37 1/2-year experience at the Texas Heart Institute.

The surgical treatment of coronary artery anomalies continues to evolve. The most common coronary artery anomalies requiring surgical intervention include coronary artery fistulae, anomalous pulmonary origins of the coronary arteries, and anomalous aortic origins of the coronary arteries. The choice of surgical intervention for each type of coronary anomaly depends on several anatomic, physiologic, and patient-dependent variables. As surgical techniques have progressed, outcomes have continued to improve, however, controversy still exists about many aspects of the proper management of patients who have these coronary artery anomalies. We reviewed the surgical treatment of 178 patients who underwent surgery for the above-mentioned types of coronary artery anomalies at the Texas Heart Institute from December 1963 through June 2001. On the basis of this experience, we discuss historical aspects of the early treatment of these anomalies and describe their present-day management.

Rare chronic gastric volvulus associated with left atrial and mediastinal compression.

We report a case of chronic gastric volvulus associated with left atrial compression in a 75-year-old woman who presented with chest pain, shortness of breath, and hypotension after elective hemiarthroplasty of the left hip. The patient's medical history included a paraesophageal hernia and gastric volvulus diagnosed in 1997 but left untreated. The present diagnosis of gastric volvulus was made on the basis of a chest radiograph and subsequent computed tomography. Echocardiography showed the volvulus compressing the left atrium. Surgery to repair the defect was successful, and there were no operative or postoperative complications. A review of the world medical literature revealed that gastric volvulus is rarely reported to cause hemodynamic compromise or compression of the heart and mediastinal structures.

Coronary obstruction by a calcific pericardial ring.

We report the unique case of a 62-year-old man whose left anterior descending artery was intermittently obstructed by a heavily calcified pericardial ring. This is a rare case in which a coronary artery has been compressed because of constrictive pericarditis.

Interrupted aortic arch in an adult single-stage extra-anatomic repair.

Interrupted aortic arch is a rare congenital malformation of the aortic arch that occurs in 3 per million live births. Defined as a loss of luminal continuity between the ascending and descending portions of the aorta, this anomaly entails a very poor prognosis without surgical treatment. To our knowledge, the world medical literature contains only 12 reports of isolated interrupted aortic arch diagnosed in adults. Nine of these patients underwent successful surgical repair, but 1 died during the early postoperative period. We describe a 10th successful surgical repair, which involved a 42-year-old woman who had an asymptomatic type B interrupted aortic arch (characterized by interruption between the left subclavian and left carotid arteries). We performed a single-stage extra-anatomic repair by placing a 16-mm extra-anatomic Dacron graft between the ascending and descending portions of the thoracic aorta and by interposing a 7-mm extra-anatomic Dacron graft between the 16-mm graft and the left subclavian artery. The patient recovered uneventfully and continued to do well 6 months later.

Outcome after simultaneous abdominal aortic aneurysm repair and aortocoronary bypass.

Myocardial infarction remains the leading cause of early and late death after abdominal aortic aneurysm (AAA) repair. Myocardial revascularization is staged either before or concomitant with AAA resection, but results are far from uniform. We retrospectively analyzed our experience with patients who underwent concomitant AAA resection and aortocoronary bypass (ACB) to examine the factors affecting early morbidity/mortality and early results. Forty-two patients (all men; mean age, 67.2 years) underwent simultaneous ACB grafting and AAA repair between 1975 and 1998. All were managed postoperatively in the cardiothoracic intensive care unit (mean stay, 6.1 days). The mean total hospital stay was 17.2 days. Two died in the early postoperative period (4.8%): 1 of sustained myocardial failure following a third ACB, and 1 of coagulopathy after concomitant ACB, aortic valve replacement, and AAA. One patient developed a nonfatal MI on postoperative day 3. The incidence of wound and bleeding complications was higher for patients undergoing both ACB and AAA repair than for patients undergoing AAA resection alone. On follow-up (mean, 10 years; range, 7 months to 15 years), only 2 of 10 late deaths were due to cardiovascular causes. We believe that concomitant myocardial revascularization is warranted in select patients requiring elective or urgent AAA resection in order to decrease perioperative risk and improve late survival. Cardiac failure or ischemia during aortic surgery can be prevented by proper perfusion with or without cardiopulmonary bypass. In patients undergoing simultaneous procedures, the increased risk is related to the severity of the vascular and coronary artery disease and not to the combined operations.

Hypercoagulable state leading to paraplegia in a middle-aged man.

A 37-year-old man presented with an unusual thrombotic disorder characterized by acute paraplegia and the absence of palpable pulses due to extensive arterial thrombosis of the aorta and its distal branches. The patient had an extremely complicated course that necessitated multiple revascularization procedures over a 1.5-year period. This case is unusual not only because of its complexity but also because of the patient's relatively young age, his lack of risk factors for vascular disease, and the presence of a neurologic deficit that improved when circulation was restored. More unusual, however, is the fact that all diagnoses were excluded except for a high lipoprotein(a) level. To our knowledge, this is the 1st reported case in which aortic thrombosis has been related to hypercoagulability.