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Background Left ventricular assist device (LVAD) failure and malfunction rates are critical gauges for establishing LVADs as a long-term therapy for end-stage heart failure patients. These device performance measures, however, have been inadequately characterized in the bridge-to-transplantation literature. Methods REMATCH is a randomized trial that compares optimal medical management with LVAD implantation for patients with end-stage heart failure. An independent committee adjudicated patient outcomes. The primary endpoint—survival—was analyzed by intention to treat using the log-rank statistic. Frequency of event occurrence was analyzed by Poisson regression. The time to first event was analyzed by the product limit method. Device performance was disaggregated into confirmed malfunctions and system failures. The latter were events in which patients could not be rescued with backup circulatory support measures. Results The 1-year survival rate was 52% (95% confidence limit [CL]; 40%–63%) for LVAD patients versus 28% (95% CL; 17%–39%) for medical patients and the 2-year survival rate was 29% (95% CL; 19%–40%) for LVAD patients versus 13% (95% CL; 5%–22%) for medical patients. System failure was 0.13 per patient per year and the confirmed LVAD malfunction rate was 0.90. Freedom from device replacement was 87% at 1 year and 37% at 2 years. Conclusions Despite the observed rates of device malfunction and replacement, LVAD implantation confers clinically significant improvement with regard to survival as compared with medical management. Device modifications and innovations for infection management exhibit great promise of improving device performance in the near future.

Background . Most of our patients with coronary artery disease have undergone bypass exclusively with purely internal thoracic artery grafts (PITA). Our goal has been to lengthen the time a patient benefits from coronary bypass operations. The present report describes an 8.5-year study of outcomes including mortality and the need for reintervention in patients who have undergone bypass with PITA. Methods . We studied 897 patients who underwent PITA with a total of 3,784 internal thoracic artery (ITA) grafts (4.2 grafts per patient). Connecting ITA to ITA along with sequential anastomosis made the procedure possible. Results . Early mortality for the group was 2.3%. Freedom from death was 86% and freedom from reintervention was 94% at 5 years after the operation. Conclusions . The acceptable early and late mortality and the 94% freedom from reintervention as long as 8.5 years after operation in this group of patients inspire us to continue choosing PITA for patients with three-vessel coronary artery disease.

Background . Safe transition from cardiopulmonary bypass to the HeartMate left ventricular assist device without periods of low output, air emboli, or injury to the right ventricle is vital to its successful implantation. A right atrial-to-left ventricular shunt has been developed to purge quickly and completely all air from the system and prevent its reentry, as well as to assist the right ventricle during the transition from cardiopulmonary bypass to the HeartMate. Methods . From January 1994 through July 1996, we used an extracorporeal membrane oxygenation right atrial-to-left ventricular shunt during 17 HeartMate implantations in 16 patients. The shunt consists of the existing right atrial two-stage cannula, the bypass circuit, and a separate aortic line that fills the left ventricle using a 21F cannula in the lateral ventricular wall. Air is monitored in the heart and aorta using transesophageal echocardiography. Results . Ten of the 16 patients are living and 8 have undergone transplantation. Two patients are still using the device and are awaiting transplantation. None of the patients have experienced postoperative neurologic events suggestive of air emboli. Conclusions . The extracorporeal membrane oxygenation right atrial-to-left ventricular shunt is simple and inexpensive to construct. It provides for a smoother and safer transition from cardiopulmonary bypass to the HeartMate left ventricular assist device.

Selection of the bypass graft that the patient has demonstrated will remain patent and free from critical atherosclerosis is a most important part of coronary artery bypass reoperations. Sixteen patients in whom a patent left internal thoracic artery—left anterior descending coronary artery bypass graft and obstructed or closed saphenous vein grafts to other coronary arteries were visualized underwent reoperation. To reach the inadequately perfused circumflex and right coronary arteries, the right internal thoracic artery was anastomosed to the left internal thoracic artery as a T graft and then was attached to the circumflex and right coronary artery branches. All patients survived the procedure and are free from angina. There were no perioperative myocardial infarctions, and there was no suggestion of hypoperfusion by the grafts. We believe this technique may reduce the incidence of graft failure in patients undergoing reoperative coronary artery bypass grafting.

Background Given the large number of patients undergoing cardiac operations annually, it is important to identify populations at high risk for adverse outcomes. This observational study was conducted to determine the incidence of preoperative heparin-platelet factor 4 (HPF4) antibodies and to assess the associated risk of postoperative adverse outcomes in a nonselected cardiac surgery patient population. Methods Between March 2002 and December 2004, 1114 (92%) of 1209 patients undergoing cardiac surgery with heparin were tested in an unselected manner for HPF4 antibodies. Main outcome measures were HPF4 antibody seropositivity and fatal and nonfatal adverse clinical outcomes after cardiac surgery. Results Of those screened, 60 (5.4%) of 1114 had positive HPF4 antibodies preoperatively. These patients had longer mean postoperative length of stay (14.0 days versus 9.8 days, p = 0.05), a higher incidence of prolonged (≥96 hours) mechanical ventilation (20.3% versus 9.2%, p = 0.02), acute limb ischemia (5.1% versus 0.9%, p = 0.03), renal complications including dialysis (20.3% versus 10.5%, p = 0.03), and gastrointestinal complications (15.3% versus 5.9%, p = 0.01). Stepwise logistic regression analysis showed positive HPF4 antibody status to be an independent predictor for adverse outcome and was associated with a higher risk for renal complications, including dialysis (adjusted odds ratio 2.2; 95% confidence interval, 1.1 to 4.3), than was diabetes. Conclusions In this large patient series, the presence of HPF4 antibodies before surgical heparin administration was an independent and clinically significant risk factor for postoperative adverse events after cardiac surgery. An optimal preoperative cardiac surgery risk profile should include HPF4 antibody status.

Initially, the internal mammary artery (IMA) was implanted into the myocardium, and 10 years later it was anastomosed directly to coronary arteries. Our experience with the IMA started with single attached grafts. To reduce injury to the pedicle and improve anastomotic accuracy, magnification, microsurgical techniques, and cardioplegia were introduced. After establishing excellent long-term patency of the IMA and knowing of the high incidence of obstruction in saphenous vein grafts 7 to 10 years after operation, we hypothesized that multiple IMA coronary anastomoses could improve the long-term results of coronary artery bypass grafting. Bilateral IMA, sequential IMA, and IMA Y-grafts were used to increase the number of mammary coronary anastomoses to 3.1 per patient. Early clinical results and patency evaluations are encouraging. In our experience, the IMA has evolved from being implanted into the myocardium, to a single bypass graft to the left anterior descending coronary artery, and finally to being the bypass conduit of choice supplying blood to three or more obstructed coronary arteries or their branches.

Long-term patency of the internal mammary artery graft surpasses that of all other bypass conduits. The use of multiple internal mammary artery grafts should improve the long-term results following coronary artery bypass grafting. Technical factors used in mobilizing, preparing, and anastomosing the internal mammary artery are discussed in this article. Fifty-three patients received sequential attached left internal mammary artery grafts from April, 1982, to August, 1983. In 6 of these patients, the right internal mammary artery was anastomosed to a circumflex marginal branch. There were no operative deaths or instances of low cardiac output. One patient suffered anastomotic narrowing that possibly could have been prevented by excision of excess tissue from the internal mammary artery pedicle. Multiple internal mammary artery grafting should have a profound influence on the results of coronary artery bypass grafting.

The internal mammary artery (IMA) was used as a graft in 298 patients undergoing coronary bypass procedures. Two patients died during the operative period and 2 others died one year later. Most of the survivors are free of angina. Of the IMAs restudied 9 to 24 months postoperatively, 95% were patent. This group included nearly all the patients having angina after operation. There are some situations in which the IMA may have inadequate flow in comparison to the vein graft. These results suggest the IMA is an excellent graft in most coronary bypass procedures.

Data from three large groups of patients undergoing aorta-to-coronary artery saphenous vein bypass grafting with follow-up angiograms between 0 and 32 months and postoperative clinical evaluation for up to 46 months enable us to say there is an early saphenous vein closure rate of 9%. These closures are probably related to technical judgment difficulties and lend themselves to improvement in results. The documented late closure rate in 92 patients followed a mean of 31.7 months was 13%. This is a rate of one late closure per 171 patient-months. Of the 92 patients, 80 had some effective vein graft functioning in this follow-up period. Histological evaluation has revealed subintimal fibrous hyperplasia to be the predominant factor involved in late closure of the vein bypass. Its manifestations are variable, and the multifactorial etiology is as yet unclear. Since 5% of vein grafts have some significant subintimal fibrous hyperplasia at the time of insertion, only close follow-up with correlation of operative, angiographic, and histological data will provide the answers to the question of etiology of late vein graft closure. Studies on the effect of trauma, vascularity, and nutrition of vein grafts are necessary. The answer to this problem will be necessary to set the coronary vein bypass procedure on a firm footing in the treatment of coronary artery disease.

The results of combined valve replacement and coronary artery bypass in 13 patients are presented. The importance of preoperative coronary visualization in all adult patients undergoing valve replacement is emphasized. The techniques by which we have been able to carry out perfusion of the coronary arteries in these patients with coronary atherosclerosis is also demonstrated. The combined attack on both these problems should, with increasing skill, improve the results in patients with combined valve and coronary artery disease.

Ideally, autotransfusion after cardiac surgical procedures should offer the protection of underwater-seal drainage and involve additional cost to the patients only if their blood is reinfused. A technique of returning the patient's postoperatively drained blood that employs these features and that we have found to be safe, simple, and cost-effective is presented.

Three patients undergoing coronary artery bypass operation at this institution over a two-month period were found to have significant atherosclerotic disease involving the internal mammary artery. All 3 patients were relatively young men with hypertension and severe three-vessel coronary involvement. Continuing experience with the internal mammary artery plus subsequent extensive postmortem dissections have supported our impression that atherosclerosis involving the internal mammary artery is much more prevalent than previously implied. Techniques for evaluating this vessel both preoperatively and intraoperatively are discussed.

The transverse sinus route for bypassing high marginal circumflex coronary arteries facilitates the operation and obviates potential kinking sites at the left atrial appendage and pericardial reflection over the pulmonary veins. The vein bypass emerges from the transverse sinus and closely parallels the marginal circumflex coronary vessels.

To better evaluate the incidence of atherosclerosis in the internal mammary artery (IMA), 215 IMA segments from routine postmortem examinations were evaluated microscopically. Significant atherosclerotic narrowing was seen in 9 patients (4.2%). No patient had more than a 50% reduction in lumen diameter. The degree of incipient atherosclerosis correlated well with age, hypertension, diabetes, and peripheral vascular disease.

A one-year series of 196 consecutive patients who underwent coronary artery bypass operation without a hospital death is presented; included are patients who had associated intracardiac procedures. Many patients had impairment of one or more portions of their left ventricular wall. Of the 196 patients, 194 (99%) have been followed up by questionnaire 6 to 18 months postoperatively. Grading of results has been according to degree of symptom relief and level of postoperative activity. Ninety-five percent of the 194 have improved after operation, and 89% are experiencing good or excellent results. There have been 5 late deaths. The factors pertaining to the management of these patients in the preoperative, operative, and postoperative periods that have made these results possible are indicated. The criteria used in our attempt to properly select patients with ventricular impairment are also cited. Most of the patients who had a less than optimal outcome following the operative procedure were noted at operation to have severe diffuse coronary atherosclerosis.

Ten of 11 patients were successfully operated upon for severely symptomatic idiopathic hypertrophic subaortic stenosis (IHSS). The operative techniques utilized were myotomy in 9 patients, myotomy and mitral valve replacement in 1 patient, and mitral valve replacement alone in 1 patient. Intraoperative and late postoperative measurement of gradients have shown abolition of or a marked decrease in gradients in 8 patients studied. With 1 exception, all 10 survivors are now in N.Y.H.A. Functional Class I or II. One patient suffers from persistent left heart failure and remains in Class IV. Significant mitral insufficiency was abolished by operation in all but 1 patient. Myotomy is an effective and safe operative technique in the treatment of IHSS. Mitral valve replacement should be undertaken if myotomy does not relieve obstruction.

The diagnosis of perioperative myocardial infarction (PMI) in our patients was based upon electrocardiography, vectorcardiography, and postoperative enzyme changes. A group of 303 patients operated on between January and September, 1972, formed the basis of this study. Three groups were identified from among these patients. Group A was composed of 90 consecutive patients in whom MI was excluded by all criteria. Group B comprised 25 patients with proved MI and yielded the 8% incidence of MI among our patients. Group C included 34 patients with triple-vessel disease who did not sustain MI. Significantly more patients sustaining MI had preinfarction angina and severe coronary artery disease. The incidence of MI was also higher in patients with diffuse disease and those in whom the lesions could not be totally bypassed. A statistical correlation with longer pump runs and periods of anoxia was obtained. There was some suggestion that the preoperative location of the hypokinetic segment determined the site of MI in patients.