Mechanical circulatory support pathways that maximize post-heart transplant survival.

BACKGROUND: Heart transplant (HTx) recipients reach transplantation through increasing numbers of support pathways, including transition from one pathway to another. Outcomes of patients successfully bridged with various support pathways are unknown. We sought to identify mechanical circulatory support pathways that maximize survival after HTx. METHODS: A supplemented United Network Organ Sharing Dataset tracked status 1 HTx outcomes from 2000 to 2010. Recipients were grouped based on support pathway before HTx, including those transitioning from one pathway to another. Multivariable factors for time-related death were sought using Cox proportional hazard regression models. RESULTS: We identified 13,250 status 1 HTx recipients. Initial support pathways were inotropes (n = 7,607), left ventricular assist device (LVAD [n = 4,034]), intraaortic balloon pump (n = 729), biventricular assist device (n = 521), extracorporeal membrane oxygenation (ECMO [n = 316]), and right ventricular assist device (n = 43). Multivariable analysis demonstrated that LVAD use conferred a survival advantage (hazard ratio [HR] 0.71; p < 0.001), whereas all other support pathways, including inotropes (HR 1.1; p = 0.02), right ventricular assist device (HR 1.9; p = 0.01), and ECMO (HR 2.2; p < 0.001) increased the risk of post-HTx death. Support pathway transition (both escalation and reduction) occurred in 2,175 patients. Patients who transitioned from either ECMO or biventricular assist device support at listing to LVAD-only support at HTx had improved post-HTx survival that was comparable to patients who had LVAD-only therapy throughout their course (p = 0.74). CONCLUSIONS: The LVAD supported HTx recipients have better posttransplant survival than patients after all other mechanical support pathways. Survival after HTx is optimized when ECMO or biventricular assist device support can be transitioned to LVAD-only support. Our findings should aid clinical decision making and inform organ allocation policy development intended to maximize societal benefits of HTx.

Left atrial plication for heart transplantation in patients with giant left atrium.

Giant left atrium occasionally occurs in patients undergoing heart transplantation and causes a technical challenge for the surgeon because of the substantial discrepancy in size between the left atrial cuffs of the recipient and donor. We describe a left atrial plication technique that substantially reduces this discrepancy and allows for a standard left atrial anastomosis to be performed without any other modifications in technique.

Impact of single-ventricle physiology on death after heart transplantation in adults with congenital heart disease.

BACKGROUND: Prevalence of univentricular (1V) anatomy over time and whether 1V anatomy is associated with early death after heart transplant (HTx) among recipients with adult congenital heart disease (ACHD) is unknown. We investigated changes in case-mix over time, 1V vs biventricular (2V) status, and the effect of 1V anatomy on death after HTx among ACHD recipients. METHODS: The Nationwide Inpatient Sample (NIS) was used to identify ACHD HTx recipients in the United States aged 14 years or older from 1993 to 2007, divided into era 1 (1993 to 2000) and era 2 (2001 to 2007). In-hospital death was compared among recipients with 1V and 2V anatomy. Multivariable determinants associated with an increased risk of in-hospital death were sought with logistic regression models. RESULTS: From a national estimate of 509 ACHD recipients, 143 were 1V and 366 were 2V. Overall, 1V in-hospital mortality (23%) was higher than for 2V (8%; p<0.001) and remained associated with in-hospital death after adjustment for other factors (odds ratio, 3.9; 95% confidence interval, 1.29 to 11.74; p=0.02). All 1V diagnoses had higher mortality than all 2V diagnoses. Despite minor fluctuations, the proportion of 1V patients did not increase over time (era 1, 36%; era 2, 30%; p=0.46). CONCLUSIONS: Overall case-mix of ACHD recipients (1V vs 2V) has not changed over time. Initial 1V anatomy increases post-HTx death among ACHD recipients, whereas 2V patients have mortality rates similar to non-CHD recipients. National and international transplant registries should include specific CHD diagnoses because this factor plays such a large role in determining early outcomes.

Patient-specific insulin-resistance-guided infusion improves glycemic control in cardiac surgery.

BACKGROUND: Maintenance of appropriate capillary blood glucose in cardiovascular surgery patients has been associated with improved outcomes, including lower mortality. Interpatient variability in insulin resistance can make management difficult, leading to unexpected episodes of hypoglycemia and hyperglycemia. To improve postoperative glucose control at our institution, a patient-specific insulin-resistance-guided (IRG) protocol was developed. METHODS: Prospective data were gathered on 100 consecutive cardiovascular surgery patients managed with our standard insulin infusion protocol and 100 patients managed using the IRG protocol. Clinical characteristics and glycemic indices were analyzed for the two groups. Primary endpoints included (1) percentage of time spent in the target range, (2) number of hypoglycemic and hyperglycemic episodes, (3) time to achievement of target blood glucose, and (4) the total daily dose of insulin required. RESULTS: The IRG protocol resulted in significant improvements, including increased percentage of time spent in the normoglycemic range (82.5% versus 65.8%, p < 0.001), reduced rate of hypoglycemic episodes (0.12 versus 0.99, p < 0.01), reduced rate of hyperglycemic episodes (capillary blood glucose >126 mg/dL: 4.8 versus 8.2, p < 0.01), and a reduced time to the first measurement in the target range. Total daily dose of insulin was mildly increased, but failed to reach statistical significance (92.48 versus 82.64 units, p = 0.32). CONCLUSIONS: Use of the IRG protocol led to improved glycemic indices while reducing episodes of hypoglycemia in both diabetic and nondiabetic patients. The ability to adjust a patient's insulin dosing based upon factors related to their insulin resistance results in improved blood glucose control and safety in cardiovascular surgery patients.

Improved quality and cost-effectiveness of coronary artery bypass grafting in the United States from 1988 to 2005.

OBJECTIVE: This study was undertaken to assess the impact of increasing patient complexity and health care cost on coronary artery bypass grafting quality and cost-effectiveness in the United States over an 18-year period. METHODS: A retrospective study was carried out utilizing the Nationwide Inpatient Sample to track the characteristics and outcomes of 5,549,700 patients having isolated coronary artery bypass grafting in the United States from 1988 to 2005. Expected mortality, risk-adjusted mortality, and hospital charges were tracked over this period. RESULTS: The prevalence of congestive heart failure, pulmonary disease, diabetes, and acute myocardial infarction increased significantly over the study period. Expected mortality increased from 2.57% to 3.66%, reflecting the increasing patient comorbidity burden (P < .0001). Despite this, coronary artery bypass grafting outcomes improved, leading to a decrease in risk-adjusted mortality from 6.20% to 2.12% (P < .0001). Furthermore, when hospital charges were corrected for medical care inflation, hospital charges declined significantly, from $26,210 in 1988 to $19,196 in 2005 (1988 dollars, P < .0001). CONCLUSIONS: Coronary artery bypass grafting surgery is being performed on an increasingly complex, high-risk patient population in the United States. Despite this challenge, risk-adjusted operative mortality has progressively declined. Moreover, hospital charges for coronary artery bypass grafting in relation to other medical care services have been reduced. These findings reflect improved quality and cost-effectiveness of coronary artery bypass grafting in the United States. Ongoing efforts directed at quality improvement should address the risks associated with comorbidities that increasingly accompany the diagnosis of coronary artery disease in patients having coronary artery bypass grafting.

Endoscopic greater saphenous vein harvesting reduces the morbidity of coronary artery bypass surgery.

BACKGROUND: Most coronary artery bypass grafting (CABG) operations still involve the use of greater saphenous vein (GSV) for one or more grafts, even with the increasing use of arterial conduits for coronary revascularization. Wound complications from GSV harvesting are common, and sometimes severe. In order to reduce the morbidity of this procedure, we adopted a technique of endoscopic vein harvesting (EVH). EVH allows nearly complete harvest of the GSV, with excellent visualization, through minimal incisions. At our institution, a physician's assistant routinely performs EVH, usually while a cardiothoracic surgeon harvests an arterial conduit. In 1997, all GSV harvesting was performed by open technique. During a transition period in 1998 and 1999 we used several different endoscopic techniques. By the beginning of 2000, our technique of EVH was standardized and used routinely. METHODS: To determine whether EVH reduced the morbidity associated with conventional open vein harvesting (OVH), we reviewed the charts of all patients having primary coronary artery bypass operations utilizing GSV during the years 1997 and 2000. RESULTS: The two groups were comparable in risk factors for leg incision complications. The year 2000 EVH group had a marked reduction in the number of wound complications compared with the year 1997 OVH group (7.1% versus 26.1%, P < 0.00001). There were no significant differences between the two groups in total operative time (OVH 224 minutes, EVH 223 minutes, number of distal coronary anastomoses (OVH 3.38 +/- 0.90, EVH 3.38 +/- 0.94), or the rate of clinically apparent early graft failure. There was a significant increase in the use of sequential grafting techniques in the 2000 group (OVH 21.9%, EVH 43.6%, P < 0.00001). CONCLUSIONS: EVH reduced the morbidity associated with GSV harvesting. EVH was associated with an increased use of sequential coronary grafting techniques. EVH does not prolong operative time when performed by experienced personnel. We believe EVH should become the standard of care.

Robotic surgery: the computer-enhanced control of surgical instruments.

Robotic procedures are still in a developmental stage. Studies have shown that many operations can be performed safely with computer-enhanced telemanipulators, but distinct advantages of robotic procedures have not been established. Before third-party payors begin paying a premium for the use of a robot, costs will need to decrease or outcomes will need to be sufficiently better. Manufacturers of robotic surgery systems are marketing directly to consumers and promoting their systems to hospitals based on the number of patients that can be attracted by such programs. Only the acceptance of robotics into mainstream surgical practice, however, will prove it to be more than just a niche technology.