Post-heart transplant survival is inferior at low-volume centers across all risk strata.

BACKGROUND: Previous studies have demonstrated a relationship between increasing center volume and cardiac transplant outcomes. The purpose of this study was to confirm a relationship between post-heart transplant outcomes and center experience and to determine whether this relationship persists among low- and high-risk heart transplant recipient-donor pairs. METHODS AND RESULTS: The United Network for Organ Sharing (UNOS) provided deidentified patient-level data. Analysis included 8029 heart transplant recipients aged ≥18 years and transplanted between January 1, 2001 and December 31, 2006 with follow-up available through February 3, 2009. The primary outcome was observed 1-year posttransplant graft survival. Multivariable logistic regression was used to calculate expected 1-year survival for recipients. Threshold analysis identified 3 discrete risk groups of transplant recipients: high-risk, moderate-risk, and low-risk. Three discrete risk strata for center volume: low (<10.5 recipients/yr), intermediate (10.5 to 47 recipients/yr), and high (>47 recipients/yr) were also identified. χ(2) test was used to compare 1-year survival at low- and intermediate- with high-volume centers. In multivariable logistic regression analysis, annual center volume was significantly associated with posttransplant graft survival at 1 year (odds ratio [OR]=0.995, 0.992 to 0.999; P=0.010) and primary graft failure (OR=0.985, 0.972 to 0.997; P=0.015), but not stroke (OR=0.996, 0.990 to 1.003; P=0.295), infection (OR=1.001, 0.998 to 1.003; P=0.613), or dialysis (OR=1.001, 0.997 to 1.005; P=0.522). Log-rank test demonstrated significant difference in survival between volume groups with respect to high-risk (P=0.0032) and low-risk (P=0.00415), but not moderate-risk (P=0.128) patients. CONCLUSIONS: A direct relationship existed between increasing center volume and improved graft survival. Across all recipient-donor pair risk strata, posttransplant graft survival at 1 year was significantly lower at low-volume centers. The volume-outcomes relationship was strongest in the highest-risk recipient-donor category.

Designing a stentless valve conduit for use in a biological Bentall procedure.

Various modifications of the Bentall procedure have been described using mechanical valve conduits. A further modification, using a bioprosthetic valve, has grown in popularity as this prevents the need for lifelong anticoagulation. Additional innovation using a stentless bioprosthetic valve has the theoretical advantages of allowing for a larger bioprosthesis and an improved durability. The technical aspects involved in designing a stentless valve conduit for use in a biological Bentall procedure are described.

Stent Thrombosis Risk Over Time on the Basis of Clinical Presentation and Platelet Reactivity: Analysis From ADAPT-DES.

OBJECTIVES: The aim of this study was to determine the risk period for increased stent thrombosis (ST) after percutaneous coronary intervention (PCI) in patients with acute coronary syndromes (ACS) and whether this increased risk is related to high platelet reactivity (HPR). BACKGROUND: ST risk after PCI is higher among patients with ACS than those with stable ischemic heart disease. When ST risk is highest in patients with ACS and how that is affected by HPR is unknown. METHODS: Using the ADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) registry, ST rates during 2-year follow-up post-PCI with drug-eluting stents were compared among patients presenting with ACS (myocardial infarction [MI] or unstable angina) or stable ischemic heart disease (non-ACS). Landmark analyses were done at 30 days and 1 year post-PCI. Platelet reactivity on aspirin and clopidogrel post-PCI was assessed using VerifyNow assays. RESULTS: Of 8,582 patients, 2,063 presented with MI, 2,370 with unstable angina, and 4,149 with non-ACS. Incidence rates of HPR were 48.0%, 43.3%, and 39.8%, respectively (p < 0.001). Within the first 30 days post-PCI, patients presenting with MI had increased ST risk compared with patients with non-ACS (hazard ratio [HR]: 4.52; 95% confidence interval [CI]: 2.01 to 10.14; p < 0.001). After 30 days, relative ST risks were progressively lower and no longer significant between groups (31 days to 1 year post-PCI: HR: 1.97; 95% CI: 0.80 to 4.85; >1 year post-PCI: HR: 0.89; 95% CI: 0.27 to 2.92). The elevated ST risk in patients with MI within 30 days was largely confined to those with HPR on clopidogrel (HR: 5.77; 95% CI: 2.13 to 15.63; p < 0.001). CONCLUSIONS: Among patients undergoing PCI, rates of ST during 2-year follow-up were highest in those with MI and lowest in those with non-ACS. Increased ST risk in patients with MI was greatest in the first 30 days post-PCI and was observed predominantly among those with increased HPR on clopidogrel. These findings emphasize the importance of adequate P2Y12 inhibition after MI, especially within the first 30 days after stent implantation.

The evolution of minimally invasive cardiac surgery: from minimal access to transcatheter approaches.

The field of minimally invasive cardiac surgery has undergone rapid transformation over recent years. In this review, we provide a summary of the most current evidence supporting the use of minimally invasive aortic and mitral valve replacement techniques, as well as transcatheter approaches for aortic and mitral valve disease. As an adjunct, the use of robotically assisted coronary bypass surgery and hybrid coronary revascularization procedures is discussed. In order to obtain optimal patient outcomes, a collaborative, heart-team approach between cardiac surgeons and interventional cardiologists is necessary.

Low-Dose Donor Dopamine Is Associated With a Decreased Risk of Right Heart Failure in Pediatric Heart Transplant Recipients.

BACKGROUND: Previous studies in adults have suggested that donor dopamine treatment may improve recipient outcomes in organ transplantation; in this analysis, we aimed to determine if donor dopamine reduces the incidence of postoperative right heart failure (RHF) in pediatric heart transplant recipients. METHODS: Data for recipients aged 18 years or younger transplanted at our institution between January 1, 2000, and June 15, 2011, and their respective donors were obtained. The presence of postoperative RHF was assessed for in all subjects. Donor dopamine dose was stratified into 3 groups: none, low-dose (≤5 µg/kg per minute), and high-dose (>5 µg/kg per minute). Logistic regression was used to assess the relationship between donor dopamine dose and recipient RHF. RESULTS: Of 192 recipients, 34 (18%) experienced postoperative RHF. There was no difference in baseline demographics between recipients with and without RHF. When controlling for pulmonary vascular resistance index, graft ischemic time, and cardiopulmonary bypass time, donor low-dose dopamine was independently associated with a decreased risk of RHF (odds ratio, 0.16; 95% confidence interval, 0.04-0.70; P = 0.02); however high-dose dopamine was neither associated with, nor protective of, RHF (odds ratio, 0.31; 95% confidence interval, 0.06-1.6; P = 0.16). CONCLUSIONS: Despite advances in perioperative care of the recipient, RHF persists as a complication of pediatric heart transplantation. In this study, donor pretreatment with low-dose dopamine is associated with a decreased risk of postoperative RHF in pediatric heart recipients. Further studies into this association may be useful in determining the utility of empiric donor pretreatment with low-dose dopamine.

Comparative effectiveness of minimally invasive versus traditional sternotomy mitral valve surgery in elderly patients.

OBJECTIVES: This study assessed comparative effectiveness of minimally invasive versus traditional sternotomy mitral valve surgery in elderly patients. METHODS: From January 1, 2000, to December 31, 2008, 1005 patients underwent isolated mitral valve surgery at our institution. Patients ≥ 75-years-old were included in analysis (sternotomy, n = 105; minimally invasive, n = 70). Clinical outcomes included bypass and crossclamp time, length of hospitalization, morbidity, and mortality. To assess resource use, total hospital costs and discharge location were analyzed. Three standardized inpatient functional status outcomes were also assessed. RESULTS: The minimally invasive approach was associated with a 9.2-minute longer crossclamp time (P = .037) and a 25.2-minute longer bypass time (P < .001). Minimally invasive surgery was associated with a 3.1-day shorter hospitalization (P = .033). There were no significant differences in rate of major postoperative complications (P = .085) or long-term survival (P = .60). Minimally invasive approach was associated with a $6721 lower median cost of hospitalization (P = .007) and more common discharge to home, routinely or with a health aide, rather than to rehabilitation (P = .021). Minimally invasive patients achieved faster rates of independent ambulation (P = .039) and independent sit-to-stand activity (P = .003), although there were no differences in time to independent stair climbing (P = .31). CONCLUSIONS: Among elderly patients, minimally invasive mitral valve surgery is associated with slightly longer crossclamp and bypass times but with equivalent morbidity and mortality and shorter hospitalization, decreased resource use, and improved postoperative functional status.

Quantifying the incremental cost of complications associated with mitral valve surgery in the United States.

OBJECTIVE: The goal of this study was to quantify the net increase in resource use associated with complications after isolated mitral valve surgery. METHODS: Deidentified patient-level claims data on a random sample of mitral valve operations performed in the United States from January 1, 2006, to December 31, 2007, were obtained from the National Inpatient Sample (n = 16,788). Patients with major concomitant cardiac procedures were excluded from the analysis for a net sample size of 6297 patients. Risk-adjusted median total hospital costs and length of stay were analyzed by major complications, including pneumonia, sepsis, stroke, renal failure requiring hemodialysis, cardiac tamponade, myocardial infarction, gastrointestinal bleed, and venous thromboembolism. RESULTS: There were a total of 1323 complication events that occurred in 1089 patients. The most common complication was pneumonia (n = 346, 5.5%), which was associated with a $29,692 increase in hospital costs and a 10.2-day increase in median length of stay (P < .001). The most costly complication was cardiac tamponade, which resulted in an increase in hospital cost of $56,547 and an increase in length of stay of 19.3 days (P < .001). There was a stepwise association between the hospital costs and length of stay and the number of complications per patient (P < .001). There was also a significant association between the discharge location and the occurrence of a complication, with 25% more patients who underwent routine home discharge when there were no complications (P < .001). CONCLUSIONS: In patients undergoing isolated mitral valve surgery, postoperative complications were associated with significant increases in mortality, hospital costs, and length of stay, as well as with discharge location. With growing national attention to improving quality and containing costs, it is important to understand the nature and impact of complications on outcomes and costs.

Evolution of cannulation techniques for minimally invasive cardiac surgery: a 10-year journey.

OBJECTIVE: For minimally invasive cardiac surgery (MICS) procedures requiring cardiopulmonary bypass (CPB), cannulation techniques vary and seem to be important determinants of technical difficulty and clinical outcomes. Over 10 years of MICS, we have modified our techniques substantially, and the present report outlines the evolution of our current cannulation platform. METHODS: From October 2000 to November 2010, 1087 minimally invasive cardiac procedures were performed at our institution; of these, 165 were done without CPB and were excluded. Methods of arterial and venous cannulation and aortic occlusion were retrospectively reviewed. Outcomes of interest included CPB and aortic cross-clamp time, as well as rates of in-hospital stroke, myocardial infarction, and short- and long-term mortality. RESULTS: The mean age of the study population was 57 ± 15 years, with 50% being men. The MICS procedures included mitral valve surgery, atrial septal defect repair, atrial fibrillation ablation, and cardiac tumor resections. Over the study period, peripheral arterial cannulation was replaced by central aortic cannulation, which was used in 33% of patients in 2000-2001 and 93% in 2008-2010. Venous cannulation strategies also evolved over time, from percutaneous neck and femoral (78% of cases from 2000-2005), to direct superior vena cava and percutaneous femoral (67% in 2006-2007), to percutaneous dual-stage femoral (51% in 2008-2010). Aortic occlusion was achieved by endoaortic balloon in 33% of cases in 2000-2001 but, by 2002, was replaced by transaxillary clamp occlusion and direct antegrade/retrograde cardioplegia. In the post-endoballoon era, CPB and cross-clamp times have remained consistent. Overall, there were nine strokes (<1.0%), no myocardial infarctions, and 18 deaths (2.0%) within 30 days of surgery, and the incidence of these outcomes has not changed over time. CONCLUSIONS: Over 10 years, our cannulation strategy for MICS has evolved to favor central aortic over femoral arterial cannulation, percutaneous femoral dual-stage bicaval venous drainage over percutaneous neck access, and transaxillary clamping over endoaortic balloon occlusion of the aorta. In our experience, this approach has resulted in low complication rates and a reliable platform for a variety of MICS procedures.

Aortic root and right ventricular outflow tract reconstruction using composite biological valved conduits after failed Ross procedure.

The Ross procedure or pulmonary autograft has been frequently used for surgical treatment of aortic valve disease. One considerable disadvantage of the Ross procedure is the involvement of two valves (aortic and pulmonary) in treatment of single (aortic) valve disease. Both the aortic and pulmonary valves are at risk for future degeneration. Concurrent failure of both valves after a Ross procedure is rare but presents a significant technical challenge when reoperation is necessary. We describe a novel approach to this complication using composite biological valved conduits comprised of stentless bioprosthetic valves and polyester grafts.

Integrating economic evaluation methods into clinical and translational science award consortium comparative effectiveness educational goals.

With the ongoing debate over health care reform in the United States, public health and policy makers have paid growing attention to the need for comparative effectiveness research (CER). Recent allocation of federal funds for CER represents a significant move toward increased evidence-based practice and better-informed allocation of constrained health care resources; however, there is also heated debate on how, or whether, CER may contribute to controlling national health care expenditures. Economic evaluation, in the form of cost-effectiveness or cost-benefit analysis, is often an aspect of CER studies, yet there are no recommendations or guidelines for providing clinical investigators with the necessary skills to collect, analyze, and interpret economic data from clinical trials or observational studies. With an emphasis on multidisciplinary research, the Clinical and Translational Science Award (CTSA) consortium and institutional CTSA sites serve as an important resource for training researchers to engage in CER. In this article, the authors discuss the potential role of CTSA sites in integrating economic evaluation methods into their comparative effectiveness education goals, using the Columbia University Medical Center CTSA as an example. By allowing current and future generations of clinical investigators to become fully engaged not only in CER but also in the economic evaluations that result from such analyses, CTSA sites can help develop the necessary foundation for advancing research to guide clinical decision making and efficient use of limited resources.

The golden age of minimally invasive cardiothoracic surgery: current and future perspectives.

Over the past decade, minimally invasive cardiothoracic surgery (MICS) has grown in popularity. This growth has been driven, in part, by a desire to translate many of the observed benefits of minimal access surgery, such as decreased pain and reduced surgical trauma, to the cardiac surgical arena. Initial enthusiasm for MICS was tempered by concerns over reduced surgical exposure in highly complex operations and the potential for prolonged operative times and patient safety. With innovations in perfusion techniques, refinement of transthoracic echocardiography and the development of specialized surgical instruments and robotic technology, cardiac surgery was provided with the necessary tools to progress to less invasive approaches. However, much of the early literature on MICS focused on technical reports or small case series. The safety and feasibility of MICS have been demonstrated, yet questions remain regarding the relative efficacy of MICS over traditional sternotomy approaches. Recently, there has been a growth in the body of published literature on MICS long-term outcomes, with most reports suggesting that major cardiac operations that have traditionally been performed through a median sternotomy can be performed through a variety of minimally invasive approaches with equivalent safety and durability. In this article, we examine the technological advancements that have made MICS possible and provide an update on the major areas of cardiac surgery where MICS has demonstrated the most growth, with consideration of current and future directions.

A minimally invasive approach is more cost-effective than a traditional sternotomy approach for mitral valve surgery.

OBJECTIVE: The aim of this study was to compare the cost and effectiveness of a minimally invasive (MI) versus traditional sternotomy (ST) approach for mitral valve surgery (MVS). METHODS: From January 1, 2003, to December 31, 2008, a total of 847 patients underwent isolated MVS at our institution. Propensity matching on 22 clinical variables was carried out to generate a study cohort of 434 patients (217 matched pairs). Direct and indirect costs from the hospital perspective were retrospectively obtained from our finance department. Total hospital costs were further stratified into 13 standardized institutional billing categories. In addition, data on morbidity, mortality, discharge location, hospital readmissions within 1 year, and freedom from reoperation were obtained. RESULTS: Compared with ST, MIMVS was associated with a $9054 ± $3302 lower mean total hospital cost (P = .006), driven largely by a reduction in direct (P = .003) versus indirect costs (P = .06). Among the 13 billing categories, MIMVS was associated with a significant reduction in costs of cardiac imaging (P = .004), laboratory tests (P = .005), boarding and nursing (P = .001), and radiology (P = .002). More patients in the ST group required intubation for more than 72 hours (P = .019); however, there were no differences in morbidity or long-term survival (P = .334). A higher proportion of MI patients were discharged home with no nursing services (P = .018), and a higher proportion of ST patients required readmission within 1 year (P = .023). There were no differences in freedom from reoperation between groups (P = .574). CONCLUSIONS: With equivalent efficacy across a range of measures and lower costs compared with ST, MIMVS represents a cost-saving strategy for MVS.

Should heart transplant recipients with early graft failure be considered for retransplantation?

BACKGROUND: The purpose of this study was to determine if orthotopic heart transplantation performed within 90 days of an initial heart transplant (re-Tx) should be a contraindication to retransplantation based on inferior outcomes when compared with primary orthotopic heart transplantation recipients (control). METHODS: De-identified data were obtained from the United Network for Organ Sharing. The study population included all adult heart transplant recipients greater than 18 years old from 1995 to 2008 (n=26,804). Multivariable regression was performed in order to assess the simultaneous effect of multiple risk factors on posttransplant graft failure (PTGF) at 90 days. Secondary outcomes of interest included infection, stroke, and dialysis during the transplant hospitalization as well as primary nonfunction of the graft at 90 days. RESULTS: Among the study cohort, there were 90 (0.34%) re-Tx patients. Median survival in this group was 1.6 years compared with 10.5 years for controls. Unadjusted PTGF, infection, dialysis, and primary nonfunction were significantly higher (p<0.001) in the re-Tx group. After risk adjustment, however, PTGF (p=0.545), infection (p=0.696), dialysis (p=0.664), stroke (p=0.115), and primary nonfunction (p=0.531), did not differ significantly between the 2 groups. CONCLUSIONS: When controlling for pretransplant recipient characteristics, retransplantation within 90 days of a previous transplant is not associated with increased morbidity or mortality. However, unadjusted overall survival was significantly worse in the re-Tx group. This suggests that although retransplantation at 90 days alone is not a risk factor for inferior outcomes, given the significant comorbidities of these patients, the indications for retransplantation within 90 days are rare and must be critically examined.

Retroperitoneal hematoma with abdominal compartment syndrome during minimally invasive mitral valve replacement.

Although retroperitoneal hematomas most often occur secondary to trauma, they are a reported complication of ruptured aneurysms, anticoagulation therapy, and femoral vascular access. In the cardiovascular literature, retroperitoneal hematomas have occurred after percutaneous coronary interventions; however, these hematomas rarely bleed to the extent that they cause abdominal compartment syndrome. The present report describes the case of an adult patient who had a retroperitoneal hematoma develop during minimally invasive mitral valve replacement with intraoperative abdominal compartment syndrome requiring emergent surgical decompression.

Minimally invasive versus sternotomy approach for mitral valve surgery: a propensity analysis.

BACKGROUND: Over the past decade, minimally invasive (MI) mitral valve surgery has grown in popularity. The purpose of this study was to compare both short- and long-term outcomes of mitral valve repair and replacement performed through a MI versus traditional sternotomy (ST) incision using a propensity analysis approach to account for differences in baseline risk. METHODS: From January 2000 to December 2008, a total of 1,121 isolated mitral valve operations were performed at our institution (548 ST, 573 MI). Data were retrospectively collected on all patients, and a logistic regression model was created to predict selection to a MI versus ST approach. Propensity scores were then generated based on the regression model and matched pairs created using 1:1 nearest neighbor matching. There were 382 matched pairs in the analysis for a total sample size of 764, or 68.2% of the original cohort. Major outcomes of interest included cardiopulmonary bypass time, cross-clamp time, hospital length of stay, major in-hospital complications, and both short- and long-term survival. RESULTS: Cardiopulmonary bypass time was 117.1 ± 2.0 minutes in the ST group and 139.7 ± 2.6 minutes in the MI group (p < 0.0001), and cross-clamp time was 79.6 ± 1.5 minutes in the ST group and 83.7 ± 1.9 in the MI group (p = 0.106). The average hospital length of stay was 9.81 ± 0.61 days among ST patients and 7.76 ± 0.37 days among MI patients (p = 0.0043). There was no significant difference in the frequency of major in-hospital complications between groups. The mean duration of survival follow-up was 4.2 ± 2.4 years. There was no significant difference in mortality at 30 days (p = 0.622) or 1 year (p = 0.599). In addition, there was no significant difference in long-term survival between groups (p = 0.569). CONCLUSIONS: Although minimally invasive mitral valve surgery required a slightly longer cardiopulmonary bypass time, there was no difference in cross-clamp time, morbidity, or mortality, and hospital length of stay was significantly shorter when compared with matched sternotomy control patients.

Long-term outcomes with a minimally invasive approach for resection of cardiac masses.

BACKGROUND: Minimally invasive cardiac surgery has been used with increased frequency in all areas of cardiac surgery. The purpose of this study was to compare the effectiveness of a minimally invasive (MI) versus traditional sternotomy approach for the resection of cardiac masses. METHODS: From January 1, 2000 to December 31, 2007, 74 patients (36 traditional sternotomy, 38 MI) underwent surgery for isolated resection of a cardiac mass. Major outcomes of interest included cardiopulmonary bypass time, cross-clamp time, conversion to full median sternotomy, final pathologic diagnosis, tumor-free margins of specimen, length of stay, major in-hospital complications (stroke, renal failure, respiratory failure, reoperation, and infection), and survival. Mean follow-up time was 4.8 years. RESULTS: There was no significant difference in cardiopulmonary bypass time or cross-clamp time between groups. No MI cases required conversion to a full median sternotomy, and there was no evidence of new valvular insufficiency on postoperative transesophageal echocardiogram. There was also no difference between traditional sternotomy and MI groups with regard to margins of the resected specimen, nor was there a difference in the size of the resected specimen between groups. Length of stay was shorter in the MI group by 2.2 days (p = 0.044), and the proportion of strokes was also lower in the MI group (p = 0.023). There was no difference in morbidity or mortality between groups. CONCLUSIONS: A minimally invasive approach for cardiac mass resections is equally safe and effective compared with the traditional sternotomy approach. Limited surgical exposure did not compromise tumor resection margins, and the MI approach was associated with reduced hospital length of stay.