Incidence, risk factors, and prognostic impact of re-exploration for bleeding after cardiac surgery: A retrospective cohort study.

BACKGROUND: Postoperative re-exploration for bleeding (RB) is a frequent complication following cardiac surgery. We aim to assess incidence, risk factors, and prognostic significance of RB in a large cohort of cardiac patients. MATERIALS AND METHODS: We reviewed prospectively collected data for all patients who underwent cardiac surgery at our institution from 2007 to 2015. Logistic regression analysis was used to identify independent predictors of RB and specific outcomes. Propensity matching using a 1:1-ratio compared outcomes of patients who had RB with patients who did not. RESULTS: During the study period, 7381 patients underwent cardiac operations. Of them, 189 (2.6%) underwent RB. RB was an independent predictor of in-hospital mortality (Odds Ratio (OR):2.62 Confidence Interval (CI):1.38-4.96; p = 0.003), major adverse events (OR:3.94, CI:2.79-5.62; p < 0.001), gastrointestinal events (OR:3.54 CI:1.73-7.24), renal failure (OR:2.44, CI:1.23-4.82), prolonged ventilation (OR:3.83, CI:2.60-5.62, p < 0.001), and sepsis (OR:2.50, CI:1.03-6.04, p = 0.043). Preoperative shock (OR:3.68, CI:1.66-8.13; p = 0.001), congestive heart failure (OR:1.70 CI:1.24-2.32; p = 0.001), and urgent and emergent status (OR:2.27, CI:1.65-3.12 and OR:3.57, CI:1.89-6.75; p < 0.001 for both) were predictors of RB operative mortality. Operative mortality, incidence of major adverse events, gastrointestinal events, and respiratory failure were all significantly higher in the propensity matched RB group (p = 0.050, p < 0.001, p = 0.046, and p < 0.001 respectively). CONCLUSIONS: RB significantly increases in-hospital mortality and morbidity after cardiac surgery.

Usefulness of preoperative exercise tolerance to predict late survival and symptom persistence after surgery for chronic nonischemic mitral regurgitation.

Exercise duration during exercise treadmill testing (ETT) predicts long-term outcome among asymptomatic patients with mitral regurgitation. However, the prognostic value of preoperative exercise duration in patients who undergo mitral valve surgery is unknown. We examined findings among 45 prospectively followed (average 9.2 ± 4.3 years) patients (aged 54.8 ± 12.0 years, 45% men) with chronic isolated severe MR who underwent ETT before mitral valve surgery to test the hypotheses that exercise duration predicts long-term postoperative survival and persistent symptoms within 2 years after operation. During follow-up, 11 patients died; of these, 8 had persistent symptoms. Among patients who exercised >7 minutes, average annual postoperative all-cause and cardiovascular mortality risks were 0.75% (both endpoints) versus 5.4% and 4.8%, respectively, versus those who exercised ≤7 minutes (p = 0.003 all-cause, p = 0.007 cardiovascular). Exercise duration predicted postoperative deaths (p <.02 all cause, p <.04 cardiovascular) even when analysis was adjusted for preoperative variations in age, gender, medications, history of atrial fibrillation, and peak exercise heart rates. Other ETT, echocardiographic, and clinical variables were not independently associated with these outcomes when exercise duration was considered in the analysis. Preoperative exercise duration also predicted postoperative (New York Heart Association functional class ≥II) symptom persistence (p = 0.012), whereas other ETT, echocardiographic and clinical variables did not (NS, all). In conclusion, among patients who undergo surgery for chronic nonischemic mitral regurgitation, preoperative exercise duration, unlike many commonly used descriptors, is useful for predicting postoperative mortality and symptom persistence. Future research should determine whether interventions to improve exercise tolerance before mitral valve surgery can modify these postoperative outcomes.

Nonischemic mitral regurgitation: prognostic value of nonsustained ventricular tachycardia after mitral valve surgery.

BACKGROUND: Nonsustained ventricular tachycardia (VT), frequent in unoperated severe mitral regurgitation (MR), confers mortality risk [sudden death (SD) and cardiac death (CD)]. The prognostic value of VT after mitral valve surgery (MVS) is unknown; we aimed to define this prognostic value and to assess its modulation by left (LV) and/or right (RV) ventricular ejection fraction (EF) for mortality after MVS. METHODS: In 57 patients (53% females, aged 58 ± 12 years) with severe MR prospectively followed before and after MVS, we performed 24-hour ambulatory electrocardiograms approximately annually. LVEF and RVEF were determined within 1 year after MVS by radionuclide cineangiography. RESULTS: During 9.52 ± 3.49 endpoint-free follow-up years, late postoperative CD occurred in 11 patients (7 SD, 4 heart failures). In univariable analysis, >1 VT episode after MVS predicted SD (p < 0.01) and CD (SD or heart failure; p < 0.04). Subnormal postoperative RVEF predicted CD (p < 0.04). When adjusted for preoperative age, gender, etiology or antiarrhythmics, both postoperative VT and RVEF predicted CD (p ≤ 0.05). When postoperative VT and RVEF were both in the multivariable model, only subnormal RVEF predicted CD (p < 0.04). Among those with normal RVEF, VT >1 episode predicted SD (p = 0.03). CONCLUSION: Postoperative VT and subnormal RVEF predict late postoperative deaths in nonischemic MR. Their assessment may aid patient management.

Intravenous leiomyomatosis with intracardiac extension: a single-institution experience.

OBJECTIVE: The aim of this study was to outline the surgical management and outcomes for patients diagnosed with intravenous leiomyomatosis with intracardiac extension at a single institution. STUDY DESIGN: This was a retrospective review of patients diagnosed with intravenous leiomyomatosis with intracardiac extension between 2002-2008. RESULTS: Four patients were identified. The surgical approach in 3 (75%) patients was a single-stage operation. Four (100%) patients presented with cardiac symptoms: 3 (75%) with syncope and 1 (25%) with an abnormal electrocardiogram. Mean age at presentation was 48 years (range, 42-58 years). Complete resection of tumor was obtained in 1 (25%) patient and 3 (75%) patients experienced incomplete resection. Mean follow-up, including surveillance imaging, was 25.5 months (range, 8-57 months) and all 4 patients (100%) are currently free of recurrence. CONCLUSION: Surgical excision remains an effective therapy for treating patients with benign metastasizing leiomyomatosis. Incomplete surgical resection may result in favorable response.

Low-dose spironolactone: effects on artery-to-artery vein grafts and percutaneous coronary intervention sites.

The efficacy of vein grafts used in coronary and peripheral artery bypass is limited by excessive hyperplasia and fibrosis that occur early after engraftment. In the present study, we sought to determine whether low-dose spironolactone alleviates maladaptive vein graft arterialization and alters intimal reaction to coronary artery stenting. Yorkshire pigs were randomized to treatment with oral spironolactone 25 mg daily or placebo. All animals underwent right carotid artery interposition grafting using a segment of external jugular vein and, 5 days later, underwent angiography of carotid and coronary arteries. At that time, a bare metal stent was placed in the left anterior descending artery and balloon angioplasty was performed on the circumflex coronary artery. Repeat carotid and coronary angiograms were performed before euthanasia and graft excision at 30 days. Angiography revealed that venous grafts of spironolactone-treated animals had lumen diameters twice the size of controls at 5 days, a finding that persisted at 30 days. However, neointima and total vessel wall areas also were 2- to 3-fold greater in spironolactone-treated animals, and there were no differences in vessel wall layer thicknesses or collagen and elastin densities. In the coronary circulation, there were no differences between treatment groups in any vessel wall parameters in either stented or unstented vessels. Taken together, these observations suggest that low-dose spironolactone may exert a novel protective effect on remodeling in venous arterial grafts that does not depend on the reduction of hyperplastic changes but may involve dilatation of the vessel wall.

Acceptability and psychometric properties of the Minnesota Living With Heart Failure Questionnaire among patients undergoing heart valve surgery: validation and comparison with SF-36.

BACKGROUND: Health-related quality of life (HQOL) enhancement is a major objective of valvular surgery (VS), but assessments have been limited primarily to generic measures that may not be optimally responsive to intervention. Disease-specific instruments have been used in heart failure (HF), commonly associated with valve disease, but have been neither validated nor routinely applied among patients undergoing VS. METHODS AND RESULTS: We administered the Minnesota Living with Heart Failure (MLHFQ) and SF-36 questionnaires preoperatively (T(0)) to 50 patients undergoing VS and at 1 (T(1)) and 6 months (T(2)) after VS. Performance of MLHFQ was evaluated and compared with SF-36. MLHFQ completion rates were >98% (NS vs. SF-36); Cronbach's alpha was > or = 0.9 (total score, dimensions), supporting internal reliability. Confirmatory factor analysis verified good model fit for physical/emotional domain items (relative chi-squares < 3.0, critical ratios > 2.0, both instruments), supporting structural validity. Spearman coefficients correlating MLHFQ with parallel SF-36 domains were moderate to high (0.6-0.9; P < or = .001: T(0)-T(2)), supporting convergent validity. Baseline HQOL was poorest in patients with HF (P < or = .05 [both instruments]), supporting criterion validity. Responsiveness (proportional HQOL change scores: T(0) vs. T(2)) to VS was greater with MLHFQ vs. SF-36 (P < or = .002). CONCLUSIONS: Among patients undergoing VS, the MLHFQ is highly acceptable and maintains good psychometric properties, comparing favorably with SF-36. These findings suggest its utility for measuring disease-specific HQOL changes after VS.

Cardiac surgery in select nonagenarians: should we or shouldn't we?

BACKGROUND: Patients aged 90 years and older represent a rapidly growing subset of the population, many of whom are functionally limited by cardiovascular disease. Clinical decision making about cardiac surgical intervention in nonagenarians is hindered by a paucity of data examining survival outcomes in this population. METHODS: A consecutive series of nonagenarians who underwent cardiac operations between 1995 and 2004 were retrospectively reviewed. Data collection included baseline preoperative clinical status, intraoperative characteristics, and perioperative course. Area under the Kaplan-Meier survival estimate method was used to calculate mean survival. RESULTS: Cardiac surgical procedures were done in 49 patients (51% male); their mean age was 91.9 years (range, 90 to 97 years). Operative mortality was 8% (n = 4). Multivariate Cox proportional hazards models found preoperative chronic renal insufficiency (hazard ratio [HR], 4.88; 95% confidence interval [CI], 1.53 to 15.55; p = 0.007) and ejection fraction (HR, 0.96; 95% CI, 0.93 to 1.00; p = 0.033) were independently associated with death. Overall mean survival was 5.1 +/- 0.5 years (median, 5.2 years). Quality of life outcomes were similar to that of two related norm-based populations based on age and disease process. CONCLUSIONS: Cardiac surgical procedures can be performed safely and with therapeutic benefit in carefully selected nonagenarians. We consider physiologic indicators, social factors, and patient preferences to be the main determinants in the patient selection process. Our results support the need for more proactive intervention in symptomatic nonagenarian patients as it relates to earlier consideration of elective, rather than emergency cardiac operations.

Improvement of outcomes after coronary artery bypass II: a randomized trial comparing intraoperative high versus customized mean arterial pressure.

BACKGROUND AND AIM OF THE STUDY: The objective of this randomized trial was to compare the efficacy of two strategies of hemodynamic management during cardiopulmonary bypass (CPB) on morbidity, mortality, cognitive complications and deterioration in functional status. METHODS: Patients scheduled to undergo primary elective CABG were eligible. In one group, mean arterial pressure target during CPB was 80 mmHg ("high" MAP group); in the other group, MAP target was determined by patients' pre-bypass MAP ("custom" MAP group). The principal outcomes were mortality, major neurologic or cardiac complications, cognitive complications or deterioration in functional status. RESULTS: Of 412 enrolled patients, 36% were women, with overall mean age of 64.7 +/- 12.3 years. Duration of bypass was identical for the two randomization groups. Overall complication rates were similar: 16.5% of the high group and 14.6% of the custom group experienced one or more neurologic, cardiac or cognitive complications. When only cardiac and neurologic morbidity and mortality were considered, the rates were 11.7% and 12.6%, in the high and custom groups, respectively. The aggregate outcome rate, including functional deterioration, was 31.6% in the high group and 29.6% in the custom group. CONCLUSIONS: There were no statistically significant differences between the high MAP group and the custom MAP group for the combined outcome of mortality cardiac, neurologic or cognitive complications, and deterioration in the quality of life.

Reoperations on the ascending aorta and aortic root in patients with previous cardiac surgery.

BACKGROUND: First time operations on the ascending aorta are performed with low mortality, few complications, and excellent long-term results. Reoperations for aortic pathology in patients with previous cardiac surgery carry significantly more risk. Technical issues during the procedure, as well as age, preoperative New York Heart Association class, and perioperative renal dysfunction, have been shown to contribute heavily to worse outcomes. We analyzed our results with aortic reoperations with the intent of further reducing surgical risk through alterations in surgical technique or patient selection. METHODS: From July 1997 until October 2005, 147 patients having previous cardiac surgery presented with aneurysm or dissection of the ascending aorta or root. Perioperative data were retrospectively analyzed. Morbidity, mortality, and risk factors for these events were calculated. RESULTS: Eight patients expired (5.4%) after their reoperation. Significant (p < 0.05) univariate risk factors for mortality included age greater than 75 years (< 0.001), previous coronary artery bypass grafting (CABG) (< 0.008), cardiopulmonary bypass greater than 240 minutes (< 0.01), need for intraaortic balloon pump support (< 0.001), need for new CABG (< 0.007), postoperative cerebrovascular accident (< 0.032), and tracheostomy (< 0.003). Age 75 years or older (p < 0.025) was the only significant variable for death by multivariate analysis. A majority of patients (n = 87, 60%) required circulatory arrest to complete their procedure. However, neither arch involvement nor type of aortic root procedure was predictive of perioperative mortality. CONCLUSIONS: Surgery on the ascending aorta and root in patients who have had previous cardiac surgery can be performed with low mortality. Advanced age and significant coronary disease may negatively influence surgical results.

Epicardial beating heart cryoablation using a novel argon-based cryoclamp and linear probe.

OBJECTIVE: Epicardial, beating heart cryoablation for the treatment of atrial fibrillation may be limited by heat from intracardiac blood flow. We therefore evaluated the ability to create cryolesions using an argon-based cryoclamp device, which temporarily occludes blood flow and facilitates transmurality. METHODS: Six mongrel dogs underwent sternotomy. A clamp employing a 10-cm argon-based linear cryoablation device was used epicardially to isolate the pulmonary veins and left atrial appendage. After clamping of lesions, the probe was removed from the cryoclamp device, and the remaining linear lesions, analogous to the Cox maze III, were performed. Pulmonary vein stenosis was evaluated with the use of magnetic resonance imaging. Left atrial function and pulmonary venous flow velocities were assessed with transesophageal echocardiography. Transmurality was confirmed both electrically and histologically. Animals were then put to death at 30 days. RESULTS: All acute and chronic cryoclamp lesions produced conduction block. There was no change in right (RPV) or left pulmonary vein (LPV) diameter on the basis of magnetic resonance imaging at baseline and at planned death (RPV-1, 19.6 +/- 2.9 mm vs 16.9 +/- 2.8 mm, P = .22; RPV-2, 13.2 +/- 2.0 mm vs 11.8 +/- 1.6 mm, P = .22; and LPV, 12.2 +/- 2.4 mm vs 11.2 +/- 1.9 mm, P = .30). Left atrial function and pulmonary venous flow velocities were unchanged. Tissue sections determined transmurality in 93% of cryoclamp lesions and 84% of linear ablations performed with the 10-cm malleable probe. CONCLUSIONS: Epicardial application of this cryoclamp device on the beating heart produced transmural lesions, which persisted 30 days. Linear epicardial cryoablation was not as effective as the cryoclamp device at producing consistent transmural lesions. This novel, versatile device may be useful in treating patients with atrial fibrillation on the beating heart without cardiopulmonary bypass.

Heparin sensitivity test for patients requiring cardiopulmonary bypass.

Anticoagulation for the open heart surgery patient undergoing cardiopulmonary bypass (CPB) is achieved with the use of heparin. The industry standard of activated clotting time (ACT) was used to measure the effect of heparin. The commonly acceptable target time of anticoagulation adequacy is 480 seconds or greater. Some patients, however, exhibit resistance to standard dosing of heparin and do not reach target anticoagulation time (480 seconds). Antithrombin III deficiency has been previously cited as the cause of heparin resistance. Early detection of heparin resistance (HR) may avoid both the delayed start of CPB and inadequate anticoagulation, if emergency bypass is required. An anticoagulation sensitivity test (AST) was developed by adding 12 units of porcine mucosa heparin to the ACT tube (International Technidyne, celite type). Before anticoagulation, 4 mL of blood was drawn from the patient arterial line. Following the manufacturer's instructions, 2 mL of blood was added to each tube (ACT-baseline and ACT-AST). Three minutes after anticoagulation with 4 mg heparin/kg body weight, a second sample (ACT-CPB) was taken to determine anticoagulation adequacy. The ACT times of each sample were recorded for 300 procedures occurring during 2004 and were retrospectively reviewed. Heparin resistance occurred in approximately 20% of the patients (n = 61). In 54 patients, heparin resistance was predicted by the ACT-AST. This was determined by the presence of an ACT-AST time and an ACT-CPB that were both < 480 seconds. The positive predictive value was 90%, with a false positive rate of 3%. Heparin resistance occurs in patients undergoing CPB. We describe a simple and reliable test to avoid the delays of assessing anticoagulation for CPB (90% positive predictive value). Depending on program guidelines, patients can be given additional heparin or antithrombin III derivatives to aid in anticoagulation. An additional ACT must be performed and reach target times before CPB initiation. Testing of patient blood before the time of incision for sensitivity to heparin is a way to avoid a delay that can be critical in the care of the patient. Commercial tests are available, but efficacy data are limited, and they lead to added inventory expense. This method of titrating a diluted heparin additive, mixed with patient blood in a familiar ACT test, has proven to be an inexpensive and reliable test to predict patient's sensitivity to heparin.

No-clamp technique for valve repair or replacement in patients with a porcelain aorta.

BACKGROUND: Patients requiring valvular heart surgery may have circumferential calcification of the ascending aorta. A variety of creative procedures have been described for managing this "porcelain aorta." We describe a technique based on replacement of the ascending aorta and proximal arch under profound hypothermic circulatory arrest, followed by the valve procedure. METHODS: Twenty-five consecutive patients with a porcelain aorta were referred for heart valve surgery. In every case the aorta was replaced under circulatory arrest before the valve procedure. Postoperative morbidity, mortality, and univariate risk factors for death were calculated. Fisher's exact test defined significant perioperative variables with a p value less than 0.05. RESULTS: Of 25 patients, 23 (92%) survived the surgery to hospital discharge. One patient had a stroke (4%) and 2 patients (8%) required reexploration for bleeding. Risk factors for perioperative death by univariate analysis included age more than 78 years (p < 0.009), cardiopulmonary bypass time longer than 200 minutes (p < 0.0001), reexploration for bleeding (p < 0.02), need for intra-aortic balloon pump support (p < 0.001), and postoperative gastrointestinal complications (p < 0.001). CONCLUSIONS: Valve replacement or repair in the patient with a porcelain aorta can be safely accomplished with a technique based on aortic replacement under circulatory arrest. Elderly patients requiring extensive procedures and prolonged periods on bypass have a substantially increased risk for postoperative complications and death.

Surgical treatment of atrial fibrillation using argon-based cryoablation during concomitant cardiac procedures.

BACKGROUND: The development of ablative energy sources has simplified the surgical treatment of atrial fibrillation (AF) during concomitant cardiac procedures. We report our results using argon-based endocardial cryoablation for the treatment of AF in patients undergoing concomitant cardiac procedures. METHODS AND RESULTS: Sixty-three patients with AF who were undergoing concomitant cardiac procedures had the same left atrial endocardial lesion set using a flexible argon-based cryoablative device. Mean age was 65.1+/-1.3 years. Sixty-two percent had permanent AF, whereas 38% had paroxysmal AF. Mean duration of AF was 30.5+/-4.8 months. Mean left atrial diameter was 5.5+/-0.1 cm. Mean ejection fraction was 45+/-1.4%. All endocardial lesions were performed for 1 minute once tissue temperature reached -40 degrees C. Follow-up echocardiograms were obtained to determine freedom from AF. Kaplan-Meier analysis demonstrated an 88.5% freedom from AF rate at 12 months. Ablation time was 16.8+/-0.6 minutes. There were no in-hospital deaths and no strokes. Twelve patients (19%) required postoperative permanent pacemaker placement. CONCLUSIONS: Cryoablation using this flexible argon-based device for the treatment of AF during concomitant cardiac procedures was safe and effective, with 88.5% of patients free from AF at 12 months.

Comparison of open versus bedside percutaneous dilatational tracheostomy in the cardiothoracic surgical patient: outcomes and financial analysis.

BACKGROUND: The clinical and financial outcomes of a change in practice from traditional tracheostomy (open) to bedside percutaneous dilatational tracheostomies (PDT) was evaluated in patients who underwent cardiothoracic surgery. METHODS: During 3 years, 86 tracheostomies were performed in more than 4,000 patients who underwent cardiac surgery, 59 open and 27 PDT. A retrospective analysis was performed comparing clinical and financial outcomes of the two groups. RESULTS: There were no significant differences in demographics, medical histories, operations, or complications between open and PDT except the open group experienced more postoperative arrhythmias (70% [41 of 59] versus 44% [12 of 27], p < 0.05). Total savings associated with 1 year of PDT was $84,000, for a projected discounted savings of $283,000 during the study period. A sensitivity analysis of critical economic variables (number of tracheostomies per year, cost of operating room per minute, cost of intensive care unit bed per day) was included to evaluate the impact on cost savings. The net present value analysis, which discounts future savings by an appropriate interest rate, yielded a range of projected savings of PDT more than 5 years of $73,000 to $541,000 with a best estimate of $304,000 using figures established from our 3-year experience with PDT. Sensitivity analysis of the net present value for each critical variable was $227,000 per day of reduced intensive care unit length of stay, $180,000 per cost of operating room avoidance, $100,000 per intensive care unit bed cost per day, and $11,000 per additional tracheostomy per year. CONCLUSIONS: There were no significant clinical differences between open and PDT in cardiac surgery patients during the 3-year study period; however, PDT offered significant cost savings.

Does cross-clamping the arch increase the risk of descending thoracic and thoracoabdominal aneurysm repair?

BACKGROUND: Descending thoracic and thoracoabdominal aortic aneurysms may arise in the distal aortic arch. Repair of these aneurysms has been associated with increased morbidity and operative mortality. Complex surgical and endovascular techniques have reduced the risks for this cohort. We examined outcomes utilizing an approach based on simple cross-clamping of the arch. METHODS: From July 1997 to January 2004, 272 consecutive patients had aneurysm repair through the left chest. Twenty-nine requiring profound hypothermic circulatory arrest (PHCA) were excluded. Two hundred and forty-three were divided into two groups: group I (n = 60) had distal arch involvement and required cross-clamping proximal to the left subclavian artery. Group II (n = 183) were cross-clamped distal to the subclavian. Adjuncts for neurologic and renal protection were utilized as needed. RESULTS: In-hospital mortality for all 243 patients was 3.7%. There was no difference in mortality between groups (I, 3.3% vs II, 3.8%). Group I patients also had similar rates of paraplegia (I, 0% vs II, 2.2%), stroke (I, 1.2% vs II ,1.1%), and renal failure (I, 1.7% vs II, 5.5%). Group I patients had significantly more recurrent nerve palsies (I, 33% vs II, 4.9%) although this did not translate into a higher incidence of respiratory failure. CONCLUSIONS: Repair of thoracic aneurysms arising in the distal arch can be repaired with a technique based on simple cross-clamping without an increase in mortality or major neurologic injury. Recurrent nerve palsy is much more common with this approach but is well-tolerated without increasing the need for tracheostomy.

Management strategies for type A dissection complicated by peripheral vascular malperfusion.

BACKGROUND: End-organ malperfusion is a dreaded complication of type A aortic dissections. Different strategies have been proposed to manage this complex cohort of patients. Ideal management includes the rapid restoration of organ perfusion while avoiding catastrophic rupture and tamponade. We present our experience with primary aortic repair as the optimal method of patient management. METHODS: From July 1997 until April 2003, 101 patients underwent dissection repair and were assessed for malperfusion of the central nervous system, renal, visceral or extremity circulation. Patients with coronary artery malperfusion were analyzed separately. Aortic repair was performed expeditiously utilizing femoral bypass, circulatory arrest, and antegrade perfusion after completion of the distal anastomosis. Persistent malperfusion led to additional procedures. In-hospital morbidity, end-organ salvage, and mortality were determined. Chi-square analysis defined variables contributing significantly to outcome. RESULTS: Twenty-three patients presented with malperfusion. The operative mortality for the entire cohort with malperfusion, 4.4% (n = 1), was not greater than those without it, 5.1% (n = 4). Five patients required additional procedures following aortic repair, a majority in patients with persistent extremity ischemia. All deficits resolved except for one patient with spinal ischemia and one with visceral ischemia. Visceral malperfusion was highly lethal with a mortality of 33% (n = 1). All other patients presenting with malperfusion survived to discharge. CONCLUSIONS: Patients with malperfusion in the setting of acute type A dissection should undergo immediate aortic reconstruction as the primary means of reestablishing end-organ perfusion. Early postoperative intervention for persistent deficits leads to a gratifyingly high rate of end-organ salvage.

Outcomes of cardiac surgery in nonagenarians: a 10-year experience.

BACKGROUND: With an increasing awareness of health issues and greater emphasis on preventive medicine, the general population is living longer and healthier lives than ever before. Physicians are taking care of older patients, many of whom may require cardiac surgical procedures. Improving cardiopulmonary bypass technology allows for safer procedures with reduced morbidity and mortality even in older patients. METHODS: We have performed a retrospective analysis of 42 consecutive nonagenarian patients who underwent open-heart procedures over a 10-year period (1993 to 2002) at our institution. Their demographic profiles, operative data, perioperative results, and long-term outcomes were recorded and analyzed. RESULTS: Twenty-two women and 20 men with an age range of 90 to 97 years (mean, 91.4 years) had open-heart surgery over the study period. The complication rate was 67% overall, consisting of 7% respiratory (pneumonia, respiratory failure, reintubation), 7% hemorrhagic or embolic (postoperative bleeding, cerebral vascular accident), 12% infectious (wound infection, sepsis), and 31% new arrhythmia (atrial fibrillation, atrial flutter, ventricular tachycardia, ventricular fibrillation). Despite these complication rates, average hospital stay was 17.5 days (median, 11 days), with an intensive care unit stay of 12.0 days (median, 5 days). Thirty-day survival was 95% and survival to discharge was 93% (three deaths total; one cardiac arrest at hospital day 134 and two perioperative deaths; one ventricular arrhythmia, one cerebral vascular accident). The only statistically significant risk factor of mortality was emergency surgery. Currently, 81% are still alive an average of 2.53 years since surgery (range, 0.16 to 7.1 years). CONCLUSIONS: With improving techniques and greater attention to detail, the select nonagenarian can safely undergo cardiac surgery.

Diagnosis and treatment of heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a major side effect secondary to the administration of heparin. This syndrome is serious and potentially life threatening. This response is the result of antibodies formed against the platelet factor 4 (PF4)/heparin complex. The incidence of this immune-mediated syndrome has been estimated to be 1-3% of all patients receiving heparin therapy. The occurrence of HIT in patients requiring full anticoagulation for cardiopulmonary bypass (CPB), therefore, presents a serious challenge to the cardiac surgery team. The diagnosis of HIT should be based on both clinical and laboratory evidence. While functional assays, platelet aggregation tests, and the serotonin release assay can be used to support the diagnosis, the negative predictive value of these tests is generally less than 50%. In contrast, although non-functional antibody detection assays are more sensitive, they have a low specificity. HIT can be treated in several ways, including cessation of all heparin and giving an alternative thrombin inhibitor, platelet inhibition followed by heparin infusion, and the use of low molecular weight heparins. In this presentation, the pathology and current diagnostic tests, as well as the successful management of patients with HIT undergoing CPB at New York Presbyterian Hospital, are reviewed.

Negative fluid displacement: an alternative method to assess patency of arterial line cannulation.

Optimal flow rate with minimal pressure gradient is the goal of arterial cannulation for cardiopulmonary bypass (CPB). Misplacement of the arterial cannula or vascular pathology can lead to hemolysis or intimal damage with subsequent aortic dissection. The risk of dissection with aortic cannulation is low, 0.04-0.2% for ascending aortic cannulation and 0.2-3% for femoral cannulation. However, dissection-related mortality is significant. Common methods for assessing adequacy of arterial cannulation include minimal pressure when injecting 100-mL boluses and the presence of pulsation in the cannula. Using these techniques, misplacement of the cannula can be masked due to the small amount of volume that is transfused during the assessment. Displacement of fluid into a cannula that is in a false lumen or close to the intimal surface may not indicate a misplaced arterial cannula. Negative fluid displacement is an alternative method of evaluating the integrity of arterial cannulation. During retrograde arterial priming (RAP), fluid is drained from the arterial cannula into a collection bag. Absence of fluid return or a flow < 500 mL/minute is indicative of either arterial line occlusion or cannula misplacement. At this point, the arterial cannula can be repositioned prior to instituting CPB. Since using this technique in over 13000 bypass procedures, we have had only one dissection. This one event occurred during partial occlusion clamping of the ascending aorta. With increased use of femoral cannulation for minimally invasive cardiac surgical procedures, this RAP technique can enhance the perfusionist's and the surgeon's ability to safely perform bypass in the presence of higher dissection risk.

Ruptured descending and thoracoabdominal aortic aneurysms.

BACKGROUND: Advances in end-organ protection have dramatically reduced the incidence of the life-threatening complications associated with the elective repair of thoracoabdominal and descending thoracic aortic aneurysms. However, in the setting of a ruptured thoracic aneurysm, one may not have the luxury of complex end-organ support. We analyzed our experience with ruptured thoracic aneurysms to define morbidity and mortality in the present era. METHODS: One hundred seventy-two patients with thoracoabdominal or descending thoracic aneurysms were operated on between July 1997 and October 2001. Forty presented with either a contained or free rupture. Three techniques were used for aortic reconstruction: clamp and sew, left heart bypass, and hypothermic circulatory arrest. Adjuncts for neurologic and renal support were used when circumstances and anatomy permitted. RESULTS: Seven of 40 patients died in the hospital (17.5%). Four patients died intraoperatively, all of acute myocardial infarction. Five of the seven deaths were in patients who presented in shock. Two patients (5%) experienced paraplegia, 3 (7.5%) had renal failure requiring hemodialysis, 8 (20%) required a tracheostomy, and 6 (15%) had recurrent nerve palsies. There was one stroke (2.6%). Mean diameter of ruptured aneurysms was 8.5 cm. CONCLUSIONS: Ruptured thoracic aneurysms can be repaired with a gratifying rate of salvage. Rapid diagnosis and triage for repair is necessary to avoid progressive deterioration into shock. The incidence of myocardial infarction, and the mortality associated with this event, underscores the need for aggressive cardiac evaluation in the elective thoracic aneurysm patient. The size at rupture also emphasizes the need for earlier referral for elective aneurysm repair.