Beating heart surgery reduces mortality in the reoperative bypass patient.

BACKGROUND: Reoperative coronary artery bypass grafting (redo-CABG) has an increased operative morbidity and mortality compared to patients undergoing primary revascularization. In an effort to reduce the hazards of reoperative CABG, we commenced revascularizing selected patients without cardiopulmonary bypass (CPB) as an alternative to conventional approaches. METHODS: From January 1998 to Dec. 2000, 432 patients underwent reoperative CABG, 153 patients (35%) without the aid of CPB. Treatment groups were compared by means of univariate analysis for preoperative risk factors and postoperative complications. Predicted risk and risk-adjusted mortality were determined by the Society of Thoracic Surgeons risk algorithm. RESULTS: There was a significant difference in the preoperative predicted risk scores between the two treatment groups (off pump 6.5% vs. on pump 5.4%, p=0.0343). There was a significant difference in the off pump observed mortality (2.61%) versus the on pump group (9.68%, p=0.0065). Decreased morbidity in the off pump group was evidenced by a reduced need for blood products (25% vs. 67%, p<0.0001), and the incidence of prolonged ventilation (4% vs. 14%, p=0.0032). The off pump group also had shorter hospital stays (6.2 +/- 5.96 days vs. 8.0 +/- 7.82, p=0.0091). No significant differences between the two groups were seen in the prevalence of perioperative myocardial infarction, stroke, renal failure, or reoperation for bleeding. CONCLUSION: Bypass grafting without CPB significantly decreases mortality and morbidity in selected reoperative patients, and should be considered a viable alternative to conventional approaches.

Left mini-thoracotomy for beating heart bypass grafting: a safe alternative to high-risk intervention for selected grafting of the circumflex artery distribution.

BACKGROUND: Progression of disease and bypass graft attrition results in a population of patients who require repeated coronary interventions. Frequently, these patients have patent internal mammary artery grafts and require isolated intervention to the circumflex distribution. As an alternative to high-risk repeated sternotomy and conventional bypass surgery or catheter-based intervention, the circumflex marginal vessels may be approached by thoracotomy. We reviewed our experience in revascularizing the circumflex distribution with off-pump techniques via left mini-thoracotomy. METHODS AND RESULTS: Thirty-two patients underwent off-pump bypass grafting of the circumflex vessels via thoracotomy from December 1995 to April 2000. Twenty-seven patients presented with circumflex disease after having previous bypass grafting. Five patients, who presented with circumflex disease and either nondiseased or ungraftable disease in their other arteries, were revascularized as a primary procedure. There was no observed mortality. Seven patients (22%) required inotropes on leaving the operating room, and 3 patients (9.4%) received transfusion of packed red blood cells. There was 1 reoperation for bleeding and 1 patient with a postoperative neurological deficit. There were no perioperative myocardial infarctions. The average length of stay was 4.8 days from time of surgery to discharge. CONCLUSIONS: Off-pump grafting via thoracotomy provides a safe and effective alternative approach for patients requiring limited revascularization. Potential cardiac injury and danger to viable grafts from repeated sternotomy is minimized, and manipulation of the diseased ascending aorta is avoided. Morbidity, hospital length of stay, and cost are less than for conventional repeated coronary bypass surgery.

Influence of diabetes on mortality and morbidity: off-pump coronary artery bypass grafting versus coronary artery bypass grafting with cardiopulmonary bypass.

BACKGROUND: Myocardial revascularization in diabetic patients is challenging with no established optimum treatment strategy. We reviewed our coronary artery bypass grafting experience to determine the impact of eliminating cardiopulmonary bypass on outcomes in diabetic patients relative to nondiabetic patients. METHODS: From January 1995 through December 1999, 9,965 patients, of whom 2,891 (29%) had diabetes, underwent isolated coronary artery bypass grafting. Diabetic and nondiabetic patients were further divided into groups on the basis of cardiopulmonary bypass use. Twelve percent (346 of 2,891) of diabetic patients and 12% (829 of 7,074) of nondiabetic patients underwent coronary artery bypass grafting without cardiopulmonary bypass; the remainder had coronary artery bypass grafting with cardiopulmonary bypass. Nineteen preoperative variables were compared among treatment groups by univariate analysis. RESULTS: Patients undergoing coronary artery bypass grafting without cardiopulmonary bypass compared with those having coronary artery bypass grafting with cardiopulmonary bypass had higher mean predicted mortalities (diabetic, 3.96% versus 3.72%, p = 0.83; nondiabetic, 3.03% versus 2.86%, p = 0.79). In nondiabetic patients, coronary artery bypass grafting without cardiopulmonary bypass provides an actual and risk-adjusted survival advantage over coronary artery bypass grafting with cardiopulmonary bypass (1.81% versus 3.44%, p = 0.0127; risk-adjusted mortality, 1.79% versus 3.61%, p = 0.007). This survival benefit of coronary artery bypass grafting without cardiopulmonary bypass was not seen in diabetic patients (2.89% versus 3.69%, p = 0.452; risk-adjusted mortality, 2.19% versus 2.98%, p = 0.42). Diabetic patients undergoing coronary artery bypass grafting without cardiopulmonary bypass had fewer complications, including decreased blood product use (34.39% versus 58.4%, p = 0.001), and reduced incidence of prolonged ventilation (6.94% versus 12.10%, p = 0.005), atrial fibrillation (15.90% versus 23.26%, p = 0.002), and renal failure requiring dialysis (0.87% versus 2.75%, p = 0.036). CONCLUSIONS: The survival advantage in nondiabetic patients treated with coronary artery bypass grafting without cardiopulmonary bypass is not apparent in diabetic patients. Coronary artery bypass grafting without cardiopulmonary bypass in diabetic patients is nevertheless associated with a significant reduction in morbidity.

Off-pump bypass grafting is safe in patients with left main coronary disease.

BACKGROUND: Because of a concern about the ability to tolerate beating heart grafting, patients with left main coronary artery stenosis have been excluded from off-pump bypass. We reviewed our experience with off-pump coronary artery bypass grafting for patients with left main coronary artery disease. METHODS: Eight hundred twenty-three patients underwent bypass grafting for left main coronary artery disease from January 1998 to October 1999. One hundred patients were revascularized without the use of cardiopulmonary bypass and compared with a contemporaneous cohort of 723 patients who underwent grafting with the aid of cardiopulmonary bypass. All patients had multivessel grafting performed through a sternotomy. RESULTS: There was one death (1%) in the group undergoing off-pump grafting as compared with a 30-day mortality of 4.7% (p = 0.059) in the on-pump group. Univariate analysis established that patients revascularized without cardiopulmonary bypass were significantly less likely to require postoperative inotropic support (23% versus 62%, p < 0.001) and transfusion (35% versus 67%, p < 0.001). Logistic regression analysis revealed that cardiopulmonary bypass was an independent risk factor for mortality (odds ratio, 7.3; 95% confidence interval, 1.34 to 138.4). CONCLUSIONS: Coronary artery bypass grafting using off-pump techniques are safe and effective in left main coronary artery disease.

Lung cancer. Surgical approaches and incisions.

With the emphasis of current surgical practice being increasingly focused on reducing the invasiveness of procedures, new techniques and concepts are changing the approach to thoracic surgery. Robotics offers the benefits of scaled motion, tremor filtration, and remote telemanipulation. It may be theoretically possible to introduce the concept of telementoring into thoracic surgery. By coupling two consoles, it would be possible for a senior surgeon to guide a junior surgeon through an endoscopic procedure in which the clinicians were in different locations. The use of telepresence surgery would also enable surgeons to perform or assist in operations taking place in remote locations. Robotics has the potential to increase the applicability of endoscopic surgery to an increasing number of patients with technically complex thoracic problems. Given that this technology is in its infancy, it remains too early in the process to determine if robotics will be a significant "value-added" element of cardiothoracic surgery; however, the possibilities continue to be limited only by imagination and ingenuity.

Improved survival rates support left ventricular assist device implantation early after myocardial infarction.

OBJECTIVES: Implantation of left ventricular assist devices (LVADs) early after acute myocardial infarction (MI) has traditionally been thought to be associated with high mortality rates due to technical limitations and severe end-organ dysfunction. At some experienced centers, doctors have refrained from earlier operation after MI to allow for a period of hemodynamic and end-organ stabilization. METHODS: We retrospectively investigated the effect of preoperative MI on the survival rates of 25 patients who received a Thermocardiosystems Incorporated LVAD either <2 weeks (Early) (n = 15) or >2 weeks (Late) (n = 10) after MI. Outcome variables included perioperative right ventricular assistance (and right-sided circulatory failure), hemodynamic indexes, percent transplanted or explanted, and mortality. RESULTS: No statistically significant differences were demonstrated between demographic, perioperative or hemodynamic variables between the Early and Late groups. Patients in the Early group demonstrated a lower rate of perioperative mechanical right ventricular assistance, but had a higher rate of perioperative inhaled nitric oxide use. In addition, 67% of patients in the Early group survived to transplantation and 7% to explantation, findings comparable to those in the Late group (60% and 0% respectively). CONCLUSIONS: This clinical experience suggests that patients may have comparable outcomes whether implanted early or late after acute MI. These data therefore support the early identification and timely application of this modality in post-MI LVAD candidates, as this strategy may also reveal a subgroup of patients for whom post-MI temporary LVAD insertion may allow for full ventricular recovery.

Multivessel coronary bypass grafting without cardiopulmonary support.

Coronary artery bypass grafting without the aid of cardiopulmonary bypass (CPB) continues to gain popularity as an alternative to standard techniques of revascularization. CPB with cardioplegic arrest is associated with complications that may negate an otherwise technically flawless procedure. Experience has identified aspects crucial to the success of off-pump bypass grafting, such as patient selection, anesthetic and operative technique, and grafting sequence. We review recent technical advances and reported results for multivessel bypass grafting without CPB.

Alternative technique of right-sided outflow cannula insertion for right ventricular support.

Right ventricular assist devices are an important part of the armamentarium of cardiac surgeons for the treatment of right-sided circulatory failure after cardiac transplantation or insertion of a left ventricular assist device. However, right ventricular assist device insertion can be technically challenging in the setting of pulmonary hypertension because of a number of concomitant anatomic and physiologic phenomena. We present a technique for the insertion of the right ventricular assist device outflow cannula that is easier and faster to insert, and safer to explant, especially if cardiopulmonary bypass is to be avoided.

Ionic versus nonionic MR imaging contrast media: operational definitions.

An experimental rationale is provided to differentiate between the terms ionic and nonionic for magnetic resonance (MR) imaging contrast media such as gadodiamide and gadopentetate dimeglumine. Four independent types of physical measurements (electric conductivity, osmolality, electrophoresis, and ion exchange) were performed on a range of test compounds, including D-glucose, iohexol, gadopentetate dimeglumine, and gadodiamide. Iohexol, D-glucose, and gadodiamide are shown to be nonionic species at physiologic pH (7.4), not measurably dissociating in solution. A range of gadopentetate salts behave as electrolytes, dissociating into constituent charged ions in aqueous media. Operational definitions for the terms ionic and nonionic are provided, and the terms neutral and net zero charge are compared with nonionic for accuracy. The nomenclature nonionic and ionic is deemed appropriate for differentiating MR imaging contrast media.