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Few studies of learning in the health care sector have analyzed measures of process, as opposed to outcomes. We assessed the learning curve for a new cardiac surgical center using precursor events (incidents or circumstances required for the occurrence of adverse outcomes).Intraoperative precursor events were recorded prospectively during major adult cardiac operations, categorized by blinded adjudicators, and counted for each case (overall and according to these categories). Trends in the number of precursor events were analyzed by hospital and by defining 10 equal-sized groups across time, as were trends in outcomes obtained from institutional databases. Results from the first 101 cases performed at a new cardiac surgical site (hospital A) were compared with 2 established centers.A steep reduction in the total number of precursor events over time was observed in the early experience of hospital A (9.2 +/- 4.9 to 2.0 +/- 1.2 events per case, from first to last decile of time, P(trend).0001) compared with qualitatively stable levels in the other hospitals; this reduction was driven largely by decreases in the minor severity (P(trend).0001), compensated (P(trend).0001), and environment (P(trend).0001) categories of precursor events. No detectable changes over time were observed in postoperative mortality and complications. No significant improvement was observed in patient comorbid conditions or medical status over time to explain the trend in hospital A.Analyzing and targeting specific kinds of process-related failures (precursor events) may provide a novel and sensitive means of tracking, deconstructing, and optimizing organizational learning in medicine.

OBJECTIVE: To determine whether near infrared spectroscopic measurement of tissue pH and Po2 has sufficient accuracy to assess variation in tissue perfusion resulting from changes in blood pressure and metabolic demand during cardiopulmonary bypass. DESIGN: Prospective clinical study. SETTING: Academic medical center. SUBJECTS: Eighteen elective cardiac surgical patients. INTERVENTION: Cardiac surgery under cardiopulmonary bypass. MEASUREMENTS AND MAIN RESULTS: A near infrared spectroscopic fiber optic probe was placed over the hypothenar eminence. Reference Po2 and pH sensors were inserted in the abductor digiti minimi (V). Data were collected every 30 secs during surgery and for 6 hrs following cardiopulmonary bypass. Calibration equations developed from one third of the data were used with the remaining data to investigate sensitivity of the near infrared spectroscopic measurement to physiologic changes resulting from cardiopulmonary bypass. Near infrared spectroscopic and reference pH and Po2 measurements were compared for each subject using standard error of prediction. Near infrared spectroscopic pH and Po2 at baseline were compared with values during cardiopulmonary bypass just before rewarming commenced (hypotensive, hypothermic), after rewarming (hypotensive, normothermic) just before discontinuation of cardiopulmonary bypass, and at 6 hrs following cardiopulmonary bypass (normotensive, normothermic) using mixed-model analysis of variance. Near infrared spectroscopic pH and Po2 were well correlated with the invasive measurement of pH (R2 =.84) and Po2 (R 2 =.66) with an average standard error of prediction of 0.022 +/- 0.008 pH units and 6 +/- 3 mm Hg, respectively. The average difference between the invasive and near infrared spectroscopic measurement was near zero for both the pH and Po2 measurements. Near infrared spectroscopic Po2 significantly decreased 50% on initiation of cardiopulmonary bypass and remained depressed throughout the bypass and monitored intensive care period. Near infrared spectroscopic pH decreased significantly during cardiopulmonary bypass, decreased significantly during rewarming, and remained depressed 6 hrs after cardiopulmonary bypass. Diabetic patients responded differently than nondiabetic subjects to cardiopulmonary bypass, with lower muscle pH values (p =.02). CONCLUSIONS: Near infrared spectroscopic-measured muscle pH and Po2 are sensitive to changes in tissue perfusion during cardiopulmonary bypass.

Mechanical coronary artery occlusion is required for minimally invasive direct coronary artery bypass and off-pump coronary artery bypass surgery. It is important that the method of occlusion be minimally traumatic. Chronic effects of these methods have never been studied. Temporary occlusion of coronaries utilizing suture snare, silastic loop snare, and bulldog clamp was carried out in 12 Yucatan pigs. Three animals each were sacrificed acutely and at 3, 6, and 12 months. The area of occlusion of each vessel was examined by light microscopy and the degree of damage recorded. In the animals sacrificed acutely, there was more damage using the suture snare than with the other 2 methods, but there was minimal damage at longer intervals. There was slight damage acutely and chronically with the bulldog technique. No damage was seen acutely with the silastic loop technique, but some late damage was found. The techniques of coronary artery dissection and occlusion used for minimally invasive and off-pump bypass surgery may contribute to early postoperative graft occlusion.

Objectives The study was done to derive the optimum definition of complete revascularization in coronary artery bypass surgery. Background “Complete revascularization” has been considered the goal of coronary artery bypass operations, but various definitions of completeness exist. Methods We evaluated the Bypass Angioplasty Revascularization Investigation (BARI) surgical results in the seven years after operation. Different definitions of completeness of revascularization were retrospectively applied to the 1,507 patients in the combined randomized/registry group to derive the definition of complete operative revascularization with the best discrimination in long-term results between those with and without complete revascularization as defined. Four definitions were evaluated: 1) traditional complete revascularization with one graft to each major diseased artery system; 2) functional complete revascularization with one graft to all diseased major or primary segmental vessels; 3) number of distal anastomoses greater than, equal to or less than the number of diseased coronary segments; and 4) number of distal anastomoses to the major coronary systems equal to 1 or greater than 1. Results No independent survival advantage existed for traditional or functional complete revascularization as compared with incomplete revascularization. No survival advantage existed for any of the three arms of definition 3. For definition 4, seven-year death/myocardial infarction was highest (32.9%) when more than one anastomosis was constructed to any non-left anterior descending coronary artery (LAD) system (relative risk 1.37, p = 0.03). No increased risk was associated with constructing more than one anastomosis into the LAD system. Conclusions The construction of more than one graft to any system other than the LAD appears to confer no long-term advantage, and may actually be deleterious.

Atrial fibrillation (AF) is common after cardiac surgery and adds significant cost and morbidity. The use of prophylactic pacing strategies to prevent post-operative AF has been controversial. We previously performed a pilot study which suggested that the combination of beta-blockers and bi-atrial pacing (BAP) may reduce AF after cardiac surgery.

Study objectives: To evaluate the safety and efficacyof smaller-caliber drains in patients undergoing open heartsurgery. Design: A retrospective analysis of themedical records and chest radiographs assembled data on total amount ofdrainage, number of days of drainage, length of postoperative stay, appearance of postoperative chest radiographs, and need for furtherdrainage from either the pleural or pericardial spaces. Setting: A large university-based teaching hospital, where>800 open-heart procedures are performed yearly. Patientsand interventions: A total of 202 patients underwent standardopen heart surgery by one surgeon, and postoperative pleural andpericardial decompression was undertaken using small caliber, moreflexible drains connected to bulb suction. Results: Tubes were left in an average of 2.4 days, with a mean of 826.7 m, Lcollected during that time. The average postoperative length of staywas 6.7 days (median, 5 days). At or before 6-week follow-up, chestradiographs revealed moderate or large effusions in 19 patients (9.4%)in a pleural space that had been drained postoperatively. Twelvepatients (5.9%) required an additional postoperative procedure forpleural drainage (eight thoracenteses, four tube thoracostomies). Fourpatients (2.0%) required reexploration of the pericardium fortamponade. Conclusions: Use of smaller-caliber drainshave been found at our institution to be an adequate means ofdecompression of the pleural and pericardial spaces following openheart surgery, with patients rarely having clinically significantpleural effusions at 6-week follow-up.

Primary tumors of the heart, with the exception of atrial myxomas, occur rarely; tumors metastatic to or directly invasive of the heart are far more common. About 75% of primary tumors are benign, and 75% of these are atrial myxomas. The benign tumors include rhabdomyomas, fibromas, papillary fibroelastomas, hemangiomas, pericardial cysts, lipomas, hamartomas, teratomas, mesotheliomas, and paragangliomas or pheochromocytomas. The last 3 may also be malignant. The malignant tumors consist of various sarcomas: myxosarcoma, liposarcoma, angiosarcoma, fibrosarcoma, leiomyosarcoma, osteosarcoma, synovial sarcoma, rhabdomyosarcoma, undifferentiated sarcoma, reticulum cell sarcoma, neurofibrosarcoma, and malignant fibrous histiocytoma. Cardiac tumors produce a large variety of symptoms through any of 4 mechanisms. Their mass can obstruct intracardiac blood flow or interfere with valve function. Local invasion can lead to arrhythmias or pericardial effusions with tamponade. Bits of tumor can embolize, causing systemic deficits when the tumors are on the left side of the heart. Finally, the tumors may cause systemic or constitutional symptoms. Some tumors, of course, produce no symptoms and become evident as incidental findings. The most useful diagnostic tool is the echocardiogram, which in almost all cases precisely locates the tumor and defines its extent. The echocardiographic appearance may also allow quite accurate prediction of the tumor type and whether it is malignant or benign. Magnetic resonance imaging serves as the next most important test where the density of T1 and T2 images may allow tumor cell type identification. With few exceptions, these tumors require operative excision. Most benign tumors can be resected completely; a few, because of their large size, cannot be, and only tumor debulking may be possible. Heart transplantation should be considered for these patients. Many of the malignant tumors cannot be resected completely, either because of the extent of local spread and invasion or because of the frequent distant metastases. Transplantation may also be an option for those with extensive local disease. The long-term results for resected benign tumors are excellent; the long-term results for sarcomas are very poor, and there are few survivors. For patients with unresectable sarcomas, radiation and chemotherapy may be used, but without great expectation of successful results.

Hematocrit (Hct), the volume percent of red cells in blood, is monitored routinely for blood donors, surgical patients, and trauma victims and requires blood to be removed from the patient. An accurate, noninvasive method for directly measuring hematocrit on patients is desired for these applications. The feasibility of noninvasive hematocrit measurement by using near-infrared (NIR) spectroscopy and partial least-squares (PLS) techniques was investigated, and methods of in vivo calibration were examined. Twenty Caucasian patients undergoing cardiac surgery on cardiopulmonary bypass were randomly selected to form two study groups. A fiber-optic probe was attached to the patient's forearm, and NIR spectra were continuously collected during surgery. Blood samples were simultaneously collected and reference Hct measurements were made with the spun capillary method. PLS multivariate calibration techniques were applied to investigate the relationship between spectral and Hct changes. Single patient calibration models were developed with good cross-validated estimation of accuracy (∼ 1 Hct%) and trending capability for most patients. Time-dependent system drift, patient temperature, and venous oxygen saturation were not correlated with the hematocrit measurements. Multi-subject models were developed for prediction of independent subjects. These models demonstrated a significant patient-specific offset that was shown to be partially related to spectrometer drift. The remaining offset is attributed to the large spectral variability of patient tissue, and a significantly larger set of patients would be required to adequately model this variability. After the removal of the offset, the cross-validated estimation of accuracy is 2 Hct%.

OBJECTIVES The purpose of this study was to determine if atrial pacing is effective in reducing postoperative atrial fibrillation (AF). BACKGROUND Atrial fibrillation after coronary artery bypass grafting (CABG) is a common problem for which medical management has been disappointing. Atrial-based pacing has become an attractive nonpharmacologic therapy for the prevention of AF. METHODS Sixty-one post-CABG patients (mean age = 65 years) were randomized to one of three groups: no atrial pacing (NAP), right atrial pacing (RAP) or biatrial pacing (BAP). Each patient had one set of atrial wires attached to both the right and left atria, respectively, at the conclusion of surgery. Patients in the RAP and BAP groups were continuously paced at a rate of 100 pulses per minute for 96 h or until the onset of sustained AF (>10 min). All patients were monitored with Holter monitors or full disclosure telemetry to identify the onset of AF. The primary end point of the study was the first onset of sustained AF. RESULTS There was no significant difference in the proportion of patients developing AF in the three groups (NAP = 33%; RAP = 29%; BAP = 37%; p > 0.7). However, for the subset of patients on beta-adrenergic blocking agents after CABG, there was a trend toward less AF in the paced groups. There were no serious complications related to pacing, although in three patients the pacemaker appeared to induce AF by pacing during atrial repolarization. CONCLUSIONS Continuous right or biatrial pacing in the postoperative setting is safe and well tolerated. We did not find that post-CABG pacing prevented AF in this pilot study; however, the role of combined pacing and beta-blockade merits further study.

Background . Video-assisted lobectomy lacks vascular control and presents the potential for serious hemorrhage in a closed cavity. The use of a lighted, flow-directed balloon catheter in the pulmonary artery as an endovascular control device was evaluated. Methods . A modified light-bearing Swan-Ganz catheter was placed in the left or right pulmonary artery using fluoroscopy. The lit catheter was identified easily through the arterial wall at thoracoscopy. Its inflation allowed the control of proximal blood flow as required. Fully thoracoscopic lobectomy was carried out by isolating and dividing the lobar branches of the pulmonary artery, the pulmonary vein, and the bronchus in anesthetized swine. Results . Forty-two video-assisted anatomic lobectomies were completed in 30 pigs with balloon catheter control of the pulmonary artery. The balloon effectively controlled experimental hemorrhage caused by puncturing arterial branches ( n = 4). It allowed the transection of unlooped lobar arteries ( n = 42) and the main interlobar pulmonary artery ( n = 3). Catheter displacement back to the heart occurred in 5 animals and balloon catheter technical failures occurred in 3. Conclusions . The lighted, flow-directed balloon catheter was an effective means of avoiding acute hemorrhage and achieving vascular control in a swine lobectomy model.

Excessive postoperative bleeding after heart operations continues to be a source of morbidity. This prospective double-blind study evaluated epsilon-aminocaproic acid as an agent to reduce postoperative bleeding and investigated its mode of action. One hundred three patients were randomly assigned to receive either 30 gm epsilon-aminocaproic acid (51 patients) or an equivalent volume of placebo (52 patients). In a subset of these patients (14 epsilon-aminocaproic acid, 12 placebo), tests of platelet function and fibrinolysis were performed. Results: By multivariate analysis, three factors were associated with decreased blood loss in the first 24 hours after operation: epsilon-aminocaproic acid versus placebo (647 ml versus 839 ml, p = 0.004), surgeon 1 versus all other surgeons (582 ml versus 978 ml, p = 0.002), and no intraaortic balloon versus intraaortic balloon pump use (664 ml versus 1410 ml, p = 0.02). No significant differences in platelet function could be demonstrated between the two groups. Inhibited fibrinolysis, as reflected by less depression of the euglobulin clot lysis and no rise in d-dimer levels, was significant in the epsilon-aminocaproic acid group compared with the placebo group. Conclusion: The intraoperative use of epsilon-aminocaproic acid reduces postoperative cardiac surgical bleeding. (J T HORAC C ARDIOVASC S URG 1996;112:1098-107)

Although both mitral leaflets contribute equally to the preservation of left ventricular function after mitral valve replacement, most surgeons routinely excise the anterior mitral leaflet. Possible disadvantages of leaflet retention are left ventricular outflow tract obstruction and interference with prosthetic valve motion. In 31 patients undergoing mitral valve replacement, all mitral valvular and subvalvular tissue was completely retained using a technique that involved reefing the native leaflets into the valve sutures. Fifteen Carpentier-Edwards porcine and 16 St. Jude Medical valves were implanted. Two patients died of causes unrelated to this technique. In the others, echocardiography demonstrated either no or an insignificant left ventricular outflow tract gradient, and, in most, no valvular tissue could be seen in the left ventricular outflow tract. No interference with prosthetic leaflet mobility occurred. The salutary results of mitral valve replacement with complete leaflet retention recommend its use.

Splenic abscess is a rare clinical entity that is most commonly associated with infective endocarditis. Valve replacement in the setting of an unaddressed splenic abscess is associated with a high incidence of prosthetic valve infection and death. We describe 2 patients with infective endocarditis and splenic abscess treated by laparoscopic splenectomy followed by valve replacement.

Objective Most cardiac surgeons routinely perform bicaval venous cannulation for mitral valve operations. We describe the technique and advantage of a single-venous cannulation strategy. Methods/Results Single venous cannulation with a 29-French small-bore cannula (facilitated by vacuum-assisted venous drainage) yields reliable decompression of the right heart and affords outstanding exposure of the mitral valve. Conclusions We recommend and use this technique for all mitral valve operations not requiring opening the right atrium.

The ability of retrograde cardioplegia to protect the right ventricle has been questioned. Canine myocardial circulation was assessed by infusing colored microspheres through the coronary sinus. The relative flow index (RFI), a normalized measure of tissue blood flow, was determined for 76 sections of myocardium. Three distinct flow regions were evident from these measurements. A paucity of blood flow through some basal sections of the right ventricle (RFI = 0.23 +/- 0.19) was found to be significantly different (p0.005) from regions of the heart with normal flow (RFI = 1.12 +/- 0.06). Sections from the right ventricular apex demonstrated augmented flow (RFI = 3.72 +/- 1.18). These data indicate that retrograde coronary perfusion provides nonuniform flow and under some conditions may provide inadequate perfusion to portions of the right ventricle.

Bleeding from an aortic suture line or cannula site may be difficult to control, especially in the patient with a fragile or dilated aorta. This method of wrapping a vascular graft around the aorta to relieve tension on the suture line and control bleeding is simple and effective, and it facilitates obtaining the proper tension of the wrapped graft.

Background Few studies have reported long-term outcomes of surgical atrial fibrillation (AF) correction. We perform the Cox-Maze III lesion set with argon-powered cryoenergy (CryoMaze procedure) on all patients with AF presenting for cardiac operations. This study reports long-term clinical results and heart rhythm status. Methods Between July 2002 and November 2005, 119 consecutive patients underwent surgical AF correction with the CryoMaze procedure. Mitral valve disease was the primary indication for operation in 66%. AF was continuous in 65%. Rhythm assessment was with 2-week continuous electrocardiographic (ECG) monitoring in 75% of patients and by noncontinuous ECG in the remainder. Median follow-up was 3.2 years and was 98% complete. Results There was one hospital (0.8%) death. Survival at 3 years was 84%. One perioperative stroke resolved completely. No late strokes occurred. In 4 of 119 patients (4 (3.4%), pacemakers were inserted during the index hospitalization. Median length of stay was 7 days. Overall freedom from AF more than 3 years after operation was 60%. Among patients with preoperative intermittent AF, 85% (28 of 33) were in normal sinus rhythm, and 47% (27 of 58) with continuous AF were in normal sinus rhythm ( p Conclusions CryoMaze AF correction is safe and is associated with a very low risk of stroke. Rates of normal sinus rhythm at more than 3 years postoperatively were high for patients with intermittent AF and acceptable for those with continuous AF. This experience supports wider application of the CryoMaze to all patients with AF who need cardiac operations.

Background Although extensive study has been directed at the influence of patient factors and comorbidities on cardiac surgical outcomes, less attention has been focused on process. We sought to examine the relationship between intraoperative precursor events (those events that precede and are requisite for the occurrence of an adverse event) and adverse outcomes themselves. Methods Anonymous, prospectively collected intraoperative data was merged with database outcomes for 450 patients undergoing major adult cardiac operations. Precursor events were categorized by type, person most affected, severity, and compensation. Number and categories of precursor events were analyzed as predictors of a composite outcome combining death or near miss complications (DNM), using logistic regression. Results Precursor events occurred more frequently in cases with a DNM outcome than in those with no adverse event (2.7 ± 2.4 vs 2.0 ± 2.3/procedure, P = .005). After adjustment for other patient characteristics, the number of precursor events remained an independent predictor of DNM (RR, 1.14 per event [1.04 to 1.24]). Of 990 events, 35.6% related to management, 28.8% were technical, and 22.8% were environment-related. The surgeon was most affected in 40.8%, and 16.5% were of major severity. When categories of precursor events were analyzed, major severity events and those most affecting the surgeon were independent predictors of DNM. Conclusions More detailed study of process in complex operations may lead to improved quality of care and patient safety. Special attention must be paid particularly to high risk patients and high risk precursor events.

Objective: Increasing attention has been afforded to the ubiquity of medical error and associated adverse events in medicine. There remains little data on the frequency and nature of precursor events in cardiac surgery, and we sought to characterize this. Methods:Detailed, anonymous information regarding intraoperative precursor events (which may result in adverse events) was collected prospectively from six key members of the operating team during 464 major adult cardiac surgical cases at three hospitals and were analyzed with univariable statistical methods. Results:During 464 cardiac surgical procedures, 1627 reports of problematic precursor events were collected for an average of 3.5 and maximum of 26 per procedure. 73.3% of cases had at least one recorded event. One-third (33.3%) of events occurred prior to the first incision, and 31.2% of events occurred while on bypass. While 68.0% of events were regarded as minor in severity (e.g., delays and missing equipment), a substantial proportion (32.0%) was considered major and included anastomotic problems, pump failure, and drug errors. Most problems (90.4%) were reported as being compensated for, although many (30.9%) were never discussed among the team. Major events were more likely to be discussed (p < 0.0001) and less likely to have been previously encountered (p = 0.0005). Perceptions of the severity and compensation of events varied acrosstheteam,asdidtemporalpatternsofreporting(p < 0.0001).Conclusions:Awiderangeofproblematicprecursoreventsoccursduringthe majority of cardiac surgery procedures. Attention to causes and ways of preventing these precursor events could have an impact on the rate of significant errors and improve the safety of cardiac surgery.

Deep sternal wound infections continue to be an uncommon but potentially devastating complication of cardiac surgical procedures. Numerous risk factors have been identified but only a few can be characterized as modifiable. These risk factors and their modifications are reviewed in the following article.

Objectives: The objective of this study was to characterize a multiparameter fiber optic sensor for detection of changes in intramyocardial perfusion and to demonstrate a method of determining critical values for pH, PCO2, and PO2 to indicate onset of anaerobic metabolism. Methods: Six swine underwent a 20-minute occlusion of the left anterior descending coronary artery (LAD). Myocardial pH, PCO2, and PO2 were measured continuously in the LAD and left circumflex coronary artery (CFX) territories. Critical values for each parameter were calculated from these data. Results: During occlusion LAD myocardial pH declined from 7.36 ± 0.04 to 6.85 ± 0.04; PCO2 rose from 57.0 ± 2.9 to 154.0 ± 18.0 torr, PO2 fell from 78 ± 20 to 6 ± 5 torr. No myocardial pH or PCO2 changes were observed in the CFX region, however, CFX PO2 was affected in some animals during LAD occlusion and release. Methods for determining the ischemic threshold from these sensor data are presented. Conclusions: Multiparameter fiber optic sensors reliably respond to coronary occlusion and thus have the potential to help guide myocardial protection strategies for both on- and off-pump cardiac surgery. (J Card Surg 2004;19:167-174)

Two new techniques effectively control local bleeding from the heart during heart operations. Both act by achieving local tamponade of the bleeding but through different mechanisms. In the first, a glove containing a sponge is placed against the bleeding site to provide local pressure. In the second, application of focal, high vacuum suction causes forceful apposition of adjacent soft tissue. These methods have stopped bleeding in 7 patients in whom conventional methods failed.

The study was done to derive the optimum definition of complete revascularization in coronary artery bypass surgery."Complete revascularization" has been considered the goal of coronary artery bypass operations, but various definitions of completeness exist.We evaluated the Bypass Angioplasty Revascularization Investigation (BARI) surgical results in the seven years after operation. Different definitions of completeness of revascularization were retrospectively applied to the 1,507 patients in the combined randomized/registry group to derive the definition of complete operative revascularization with the best discrimination in long-term results between those with and without complete revascularization as defined. Four definitions were evaluated: 1) traditional complete revascularization with one graft to each major diseased artery system; 2) functional complete revascularization with one graft to all diseased major or primary segmental vessels; 3) number of distal anastomoses greater than, equal to or less than the number of diseased coronary segments; and 4) number of distal anastomoses to the major coronary systems equal to 1 or greater than 1.No independent survival advantage existed for traditional or functional complete revascularization as compared with incomplete revascularization. No survival advantage existed for any of the three arms of definition 3. For definition 4, seven-year death/myocardial infarction was highest (32.9%) when more than one anastomosis was constructed to any non-left anterior descending coronary artery (LAD) system (relative risk 1.37, p = 0.03). No increased risk was associated with constructing more than one anastomosis into the LAD system.The construction of more than one graft to any system other than the LAD appears to confer no long-term advantage, and may actually be deleterious.

We report the case of a 47-year-old man with AIDS who underwent a successful quadruple coronary artery bypass operation. The improving prognosis of patients with HIV/AIDS, in addition to the reported incidence of plasma lipid abnormalities in patients receiving protease inhibitors, are laying the groundwork for a larger population in which premature coronary artery disease develops. Operative risk, immunosuppressive effect of cardiopulmonary bypass, and practical considerations in the care of these patients are discussed.

Near infrared spectra and hematocrit reference measurements were collected from 37 cardiac and vascular surgery patients and calibration models developed using partial least squares analysis. Factors which influence the development of accurate models are discussed.

Prolonged cardiopulmonary bypass requiring femoral arterial cannulation may lead to ipsilateral leg ischemia. A technique described of femoral cannulation via an end-to-side femoral artery graft allows distal femoral perfusion and eliminates the complication of leg ischemia.

Warm continuous retrograde cardioplegia is thought to prevent myocardial ischemia. We tested this hypothesis by subjecting canine hearts to 2 hours of either antegrade or retrograde perfusion with normothermic blood cardioplegia. Ischemie alterations were evaluated through the measurement of myocardial pH, tissue levels of adenosine triphosphate and lactate, and the preservation of left ventricular contractility. Antegrade perfusion resulted in uniformly positive changes in the myocardial pH in both ventricles, preserved levels of adenosine triphosphate, and small increases in the myocardial lactate levels. In contrast, retrograde perfusion caused the myocardial pH to decrease, especially in the right ventricle. Tissue lactate levels rose to a significantly greater extent during retrograde perfusion and adenosine triphosphate levels declined, although not to a statistically significant degree. Finally, myocardial function, as assessed by the preload recruitable work area, was preserved (103% ± 20% of baseline) in the antegrade group but was markedly diminished (33% ± 6%) in retrogradely perfused left ventricles 35 minutes after the aortic cross-clamp was removed. These data suggest that ischemie metabolism and the subsequent alteration of myocardial function take place despite continuous retrograde perfusion with normothermic blood cardioplegia.

The results of surgical therapy performed in 51 consecutive patients with ventricular tachycardia were reviewed to determine short- and long-term predictors of success of such therapy in preventing recurrences of life-threatening ventricular arrhythmias. Of 41 patients (80%) who survived surgery, 40 had postoperative programmed stimulation and, of these patients, 78% ( n = 31) had no inducible ventricular tachycardia on no antiarrhythmic therapy. This group had a very low incidence of arrhythmia recurrence, with only one nonfatal episode of ventricular tachycardia after a mean follow-up of 41 ± 30 months. In contrast, two of the nine patients (22%) who had inducible arrhythmias postoperatively had cardiac arrest ( p = 0.12). Multivariate analysis identified two significant predictors of perioperative mortality in our patients: increased duration of cardiopulmonary bypass time and increased baseline pulmonary capillary wedge pressure. It is concluded that (1) patients who do not have inducible ventricular tachycardia after arrhythmia surgery have a very low incidence of recurrent arrhythmia and (2) prolonged time of cardiopulmonary bypass and increased pulmonary capillary wedge pressure are predictive of perioperative mortality.

A 30-year-old woman with Ebstein's anomaly presented with a sustained, wide QRS complex tachycardia exhibiting a left bundle branch block morphology. Serial electrophysiological studies revealed right and left bundle branch reentry tachycardias refractory to many conventional antiarrhyfhmic drugs, Radiofrequency and direct current catheter ablation of the right bundle branch failed to control the tachycardias. The patient subsequently underwent extensive endocardial cryoablation to the right bundle branch resulting in cure of her arrhythmia.

The effects of long-term amiodarone therapy on the defibrillation thresholds and the rate of shocks were evaluated in 62 patients who had implantation of an automatic cardioverter-defibrillator ( n = 53) or prophylactic implantation of patch electrodes ( n = 9) who were survivors of sudden cardiac death ( n = 34) or had refractory rapid ventricular tachycardia ( n = 28). There were 53 men and 9 women, with ages ranging from 18 to 76 years (mean ± SD, 60 ± 12). Coronary artery disease occurred in 50 patients (80.6%), cardiomyopathy occurred in six (9.7%), valvular heart disease developed in two (3.2%), primary electrical disease developed in two (3.2%), hypertensive heart disease materialized in one (1.6%), and Ebstein's anomaly occurred in one (1.6%). The left ventricular ejection fraction varied from 10% to 75% (mean, 37 ± 17%). All patients had falled a mean of 3.9 ± 1.6 antiarrhythmic drugs prior to implantation of the device. Twenty-eight patients (45%) were taking amiodarone up to the time of surgery, with a mean daily dose of 406 ± 147 mg (range 200 to 800) and for a mean duration of 6.0 ± 6.7 months (range 1 to 36 months). The mean defibrillation threshold (DFT) was 12.0 ± 4.4 joules (range 5 to 20) in the group taking amiodarone and was not significantly different from that of the group not taking amiodarone ( n = 32) (mean DFT 12.3 ± 5.5 joules, range 5 to 30; p = 0.77). After discharge from the hospital, 53 patients were followed for a mean of 17.8 ± 14.4 months (range 1 to 63), and 25 (47%) of them were continued on a regimen of amiodrone with a mean daily dose of 344 ± 122 mg (range 100 to 600). A total of 179 presumably appropriate shocks were registered in 8 of 25 patients (32%) taking amiodarone and 126 appropriate shocks were given in 8 of 28 patients (29%) who were not taking amiodarone. This study suggests that (1) long-term amiodarone therapy does not increase the defibrillation thresholds in patients undergoing implantation of an automatic cardioverter-defibrillator and (2) a significant number of patients receiving long-term amiodarone therapy continue to suffer from ventricular tachyarrhythmias and require repeated shocks from the device.

A 34-year-old man suffered simultaneous tears of his distal ascending and mid-descending thoracic aorta secondary to blunt trauma. Repairs of both injuries were performed via a median sternotomy approach followed by a left lateral thoracotomy using two separate methods of cardiopulmonary bypass.

• Transatrial placement of a Greenfield filter at the time of cardiac surgery was performed on three patients with recent femoral venous thrombosis and unstable angina, and at the time of pulmonary embolectomy on four others. The filter carrier was passed through the right atrial cannulation site under fluoroscopic guidance into the inferior vena cava. A preliminary vena-cavogram was performed through the carrier or a previously placed angiographic catheter. Two complications were encountered: the first was misplacement of a filter in the right renal vein before routine venacavography was employed; the second was caudal displacement of a filter by a right atrial venous drainage cannula that projected into the inferior vena cava. The latter complication can be prevented by the use of a right atrial "sump" drain that does not protrude into the inferior vena cava. ( Arch Surg . 1990;125:1222-1223)

The high cost of medical care prompted us closely to evaluate our practice of keeping all coronary artery bypass patients in the postoperative intensive care unit a minimum of 2 days. Thirty-seven patients were randomly assigned to a 1 or 2 day postoperative stay in the intensive care unit after routine bypass grafting. Nineteen patients in Group I stayed 1 day and 18 in Group II stayed 2 days. Eighteen Group I and 17 Group II patients were evaluated. No differences in type or rate of complications occurred in either group. No deaths occurred. Total hospital costs were $340 less for Group I (not statistically significant, p > 0.4), room costs were $361 less for Group I (p 0.5), and costs for arterial blood gases were $325 less for Group I (p

Two groups of elective coronary artery bypass graft (CABG) patients were compared with respect to a single variable: method of cardioplegia administration. All patients had saphenous vein grafts and all distal anastomoses were done with continuous aortic occlusion and intermittent administration of a 4° C cardioplegic solution. One hundred patients in Group I had the distal anastomoses performed before the proximal anastomoses with cardioplegic solution administered only via the aortic root. One hundred patients in Group II had the proximal anastomoses performed first so that cardioplegic solution also perfused beyond coronary obstructions as each subsequent distal anastomosis was completed. Aortic occlusion averaged 6 minutes longer in Group II (46.5 minutes) than in Group I (40.3 minutes) (p

Described is a simplified method for the insertion of separate atrial and ventricular permanent pacing electrodes. A single subclavian catheter may be used to pass both electrodes, thus facilitating the procedure.

Four groups of 12 dogs each had ligation of the left anterior descending coronary artery (LAD) with subsequent release of the ligature and confirmed reperfusion. After 24 hours of reperfusion, the hearts were removed, sliced at 1 cm intervals along the transverse axis, and stained with triphenyltetrazolium chloride. Measurements of the infarct size as a percentage of the left ventricular area (I) and of hemorrhage as a percentage of infarct size (H) were made. The duration of ligation was 3 hours in Group I, 6 hours in Group II, 18 hours in Group III, and 30 hours in Group IV. No significant difference in infarct size was found among the groups. Percent hemorrhage was 25.2% of infarct area in Group I, 28.3% in Group II, 18.1% in Group III, and 0.7% in Group IV. If reperfusion hemorrhage into an acute myocardial infarct is deleterious, these data suggest that danger to be decreased at 18 hours and absent at 30 hours after acute coronary occlusion.

In a thymoma, with lymphocytic predominance, we characterized the lymphocytes using a battery of monoclonal antibodies. The T lymphocytes had a phenotype most characteristic of cortical thymocytes (T3+, T4+, T6+, T8+, T11+, TdT+, PNA+).