Splanchnic Nerve Modulation Effects on Surrogate Measures of Venous Capacitance.

Background Splanchnic nerve modulation (SNM) is an emerging procedure to reduce cardiac filling pressures in heart failure. Although the main contributor to reduction in cardiac preload is thought to be increased venous capacitance in the splanchnic circulation, supporting evidence is limited. We examined changes in venous capacitance surrogates pre- and post-SNM. Methods and Results This is a prespecified analysis of a prospective, open-label, single-arm interventional study evaluating the effects of percutaneous SNM with ropivacaine in chronic heart failure with elevated filling pressures at rest and with exercise. Patients underwent cardiopulmonary exercise testing with invasive hemodynamic assessment pre- and post-SNM. Blood pressure changes with modified Valsalva maneuver and hemoconcentration, pre- and post-SNM were compared using a repeated measures model. Inferior vena cava diameter and collapsibility (>50% decrease in size with inspiration), and presence of bendopnea pre- and post-SNM were also compared. Fifteen patients undergoing SNM (age 58 years, 47% women, 93% with left ventricular ejection fraction ≤35%) were included. After SNM, changes in systolic blood pressure during Valsalva (peak-to-trough) were greater (41 versus 48 mm Hg, P=0.025). Exercise-induced hemoconcentration was unchanged (0.63 versus 0.43 g/dL, P=0.115). Inferior vena cava diameter was reduced (1.59 versus 1.30 cm, P=0.034) with higher collapsibility (33% versus 73%, P=0.014). Bendopnea was less (47% versus 13%, P=0.025). Conclusions SNM resulted in increased venous capacitance, associated decreased cardiac preload, and decreased bendopnea. Minimally invasive measures of venous capacitance could serve as markers of successful SNM. Long-term effects of SNM on venous capacitance warrant further investigation for heart failure management. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03453151.

Health care resource utilization and clinical outcomes for adult heart transplant recipients with primary graft dysfunction.

INTRODUCTION: The advent of new technologies to reduce primary graft dysfunction (PGD) and improve outcomes after heart transplantation are costly. Adoption of these technologies requires a better understanding of health care utilization, specifically the costs related to PGD. METHODS: Records were examined from all adult patients who underwent orthotopic heart transplantation (OHT) between July 1, 2013 and July 30, 2019 at a single institution. Total costs were categorized into variable, fixed, direct, and indirect costs. Patient costs from time of transplantation to hospital discharge were transformed with the z-score transformation and modeled in a linear regression model, adjusted for potential confounders and in-hospital mortality. The quintile of patient costs was modeled using a proportional odds model, adjusted for confounders and in-hospital mortality. RESULTS: 359 patients were analyzed, including 142 with PGD and 217 without PGD. PGD was associated with a .42 increase in z-score of total patient costs (95% CI: .22-.62; p < .0001). Additionally, any grade of PGD was associated with a 2.95 increase in odds for a higher cost of transplant (95% CI: 1.94-4.46, p < .0001). These differences were substantially greater when PGD was categorized as severe. Similar results were obtained for fixed, variable, direct, and indirect costs. CONCLUSIONS: PGD after OHT impacts morbidity, mortality, and health care utilization. We found that PGD after OHT results in a significant increase in total patient costs. This increase was substantially higher if the PGD was severe. SUMMARY: Primary graft dysfunction after heart transplantation impacts morbidity, mortality, and health care utilization. PGD after OHT is costly and investments should be made to reduce the burden of PGD after OHT to improve patient outcomes.

Predictive capabilities of the European registry for patients with mechanical circulatory support right-sided heart failure risk score after left ventricular assist device implantation.

OBJECTIVES: The prediction of right heart failure (RHF) after left ventricular assist device (LVAD) implantation remains a challenge. Recently, risk scores were derived from analysis of the European Registry for Patients with Mechanical Circulatory Support (EUROMACS) data, the EUROMACS-RHF, and the modified postoperative EUROMACS-RHF. The authors assessed the performance characteristics of these 2 risk score formulations in a continuous-flow LVAD cohort at their institution. DESIGN: A retrospective, observational study. SETTING: At a tertiary-care academic medical center. PARTICIPANTS: Adult patients who underwent durable LVAD implantation between 2015 and 2018. INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: Early post-LVAD RHF was defined as follows: (1) need for right ventricular assist device, or (2) inotropic or inhaled pulmonary vasodilator support for ≥14 postoperative days. The authors used logistic regression and examined receiver operating characteristic (ROC) curves to evaluate the ability of the 2 risk scores to distinguish between outcome groups. A total of 207 patients met the inclusion criteria. Of the patients, 16% developed RHF (33/207). The EUROMACS-RHF score was not predictive of RHF in the authors' cohort (odds ratio [OR] 1.25; 95% CI [0.99-1.60]; p = 0.06), but the postoperative EUROMACS-RHF CPB score was significantly associated (OR 1.38; 95% CI [1.03-1.89]; p = 0.03). The scores had similar ROC curves, with weak discriminatory performance: 0.601 (95% CI [0.509-0.692]) and 0.599 (95% CI [0.505-0.693]) for EUROMACS-RHF and postoperative EUROMACS-RHF, respectively. CONCLUSIONS: In the authors' single-center retrospective analysis, the EUROMACS-RHF risk score did not predict early RHF. An optimized risk score for the prediction of RHF after LVAD implantation remains an urgent unmet need.

Surgical Management of Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension is a progressive disease, which may lead to severe right ventricular dysfunction and debilitating symptoms. Pulmonary thromboendarterectomy (PTE) provides the best opportunity for complete resolution of obstructing thromboembolic disease and functional improvement in appropriately selected patients. In this article, the authors review preoperative workup, patient selection, operative technique, postoperative care, and outcomes after PTE.

A clinical investigation into the benefits of using charge codes in perioperative and critical care epidemiology: A retrospective cohort database study.

CONTEXT: Epidemiologic studies in critical care routinely rely on the codes listed in International Classification of Diseases (ICD) manuals which are primarily intended for reimbursement of claims to payers. Standardized billing codes may minimize the measurement error when used in conjunction with ICD codes. AIMS: The aim was to examine the impact of using charge codes in addition to ICD codes for ascertaining two common procedures in surgical intensive care unit (ICU) settings: hemodialysis (HD) and red blood cell (RBC) transfusions. SETTINGS AND DESIGN: This was a retrospective cohort study of Premier Inc. Database. SUBJECTS AND METHODS: Elective surgical patients aged >18 years treated in the ICU postoperatively were included in this study. This includes the ascertainment of HD and RBC transfusions in the population using a standard "ICD code" versus an "either ICD code or charge code" approach. STATISTICAL ANALYSIS USED: Descriptive analysis using t-tests, Chi-square tests as appropriate was used. RESULTS: A total of 40,357 patients were identified as having undergone elective surgery, followed by admission to an ICU across 520 US hospitals. The use of "ICD codes only" uniformly underestimated rates of HD or RBC transfusions when compared to "Charge Codes only" and "ICD Codes or Charge Codes" (% increase of 15.4%-45.6% and 50.8%-93.1%, respectively). Differences varied with specific surgical populations studied. Patients identified using the "ICD code" approach had more comorbidities, were more likely to be female, and more likely to be Medicare beneficiaries. CONCLUSIONS: Epidemiologic studies in critical care should consider using multiple independent data sources to improve ascertainment of common critical care interventions.

Association between primary graft dysfunction and acute kidney injury after orthotopic heart transplantation - a retrospective, observational cohort study.

Acute kidney injury (AKI) and primary graft dysfunction (PGD) are serious complications after heart transplantation (HT). The relationship between AKI and PGD is poorly understood. We sought to examine the incidence of AKI and identify risk factors associated with AKI. We hypothesized that PGD is one of the risk factors independently associated with post-HT AKI. We gathered data for all adult patients who underwent HT between 2009 and 2014. AKI was defined by the KDIGO criteria. PGD was categorized using ISHLT criteria. We assessed univariable and multivariable logistic regression to identify risk factors independently associated with post-HT AKI. Out of 316 patients, postoperative AKI occurred in 273 (86%) patients: 188 (68%) stage I, 44 (16%) stage II, and 41 (15%) stage III. Stage II/III AKI was associated with increased risk of mortality at 1 year. There was significant association between severe PGD and stage II/III AKI (P = 0.001, OR 3.63, 95% CI: 1.69-7.94). Other clinical factors significantly associated with stage II/III AKI included longer donor brain death duration and lower recipient baseline creatinine. We found that stage II/III AKI is common and independently associated with severe PGD. Another potentially modifiable risk factor is donor brain death duration.

Planned right ventricular support for combined heart-liver transplantation.

Right ventricular dysfunction post heart transplantation (HTx) is a common problem and its likelihood to occur after combined heart-liver transplantation is even higher. The placement of an extracorporeal planned right ventricular assist device following the HTx during liver transplantation may assist in preventing this complication.

Functional Tricuspid Regurgitation in Mitral Valve Disease.

Functional tricuspid regurgitation is a common finding in patients with left-sided heart disease. If left untreated, it may reduce survival, limit functional capacity and cause end-organ dysfunction. Annulus dilation and leaflet tethering due to right ventricle remodeling are 2 major pathophysiologic mechanisms in functional tricuspid regurgitation. Even if surgical treatment remains the gold standard, indication and timing of surgical interventions remain the object of debate in the medical community. More recently, numerous transcatheter therapies have been developed in order to offer less invasive options to patients who otherwise would have a high risk of mortality and morbidity with surgical interventions.

Outcomes in Patients Undergoing Cardiac Surgery Who Decline Transfusion and Received Erythropoietin Compared to Patients Who Did Not: A Matched Cohort Study.

BACKGROUND: Erythropoiesis-stimulating agents, such as erythropoietin (EPO), can be used to treat preoperative anemia. Some studies suggest an increased risk of mortality and thrombotic events, and use in cardiovascular surgery remains off-label. This study compares outcomes in cardiac surgery patients declining blood transfusion who received EPO with a matched cohort who did not. METHODS: After institutional review board approval, we conducted a retrospective review of all patients who decline blood transfusion who underwent cardiac surgery and received EPO between January 1, 2004, and June 15, 2015, at a single institution. Control patients who did not receive EPO and were not transfused allogeneic red blood cells perioperatively were identified during the same period. Two controls were matched to each EPO patient using an optimal matching algorithm based on age, date of surgery, gender, operative procedure, and surgeon. The European System for Cardiac Operative Risk Evaluation (EuroSCORE) and baseline characteristics remaining unbalanced in the matched cohorts were controlled for in assessing patient outcomes. The primary outcome was a composite of mortality and thrombotic events, and secondary outcomes included change in hemoglobin (Hb) from baseline to discharge, acute kidney injury (AKI), sternal wound infection, atrial fibrillation, time to extubation, intensive care unit, and hospital length of stay (LOS). RESULTS: Fifty-three patients who decline transfusion and received EPO were compared to 106 optimally matched control patients who did not receive EPO or red blood cell transfusion in the perioperative period. The median additive EuroSCORE was similar between the EPO and control group [6 (4, 9) vs 5 (3, 7), respectively; P = .39]. There was no difference in the primary outcome (P = .12) and mortality was zero in both groups. The EPO group had a higher mean preoperative Hb (13.91 g/dL vs 13.31; P = .02) and a smaller change in Hb from baseline (-2.65 vs -3.60; P = .001). The incidence of AKI (47.17% vs 41.51%; P = .49) was similar and there was no significant difference in all other outcomes, including time to extubation, hospital LOS, or intensive care unit LOS. CONCLUSIONS: In this retrospective matched cohort study of patients declining transfusion and receiving EPO matched to control patients, there were no clinically meaningful differences in the outcomes.

Intraoperative vasoplegia: methylene blue to the rescue!

PURPOSE OF REVIEW: To evaluate the efficacy, dosing, and safety of methylene blue (MTB) in perioperative vasoplegic syndrome (VS). RECENT FINDINGS: Vasoplegic syndrome is a state of persistent hypotension with elevated cardiac output, low filling pressures, and low systemic vascular resistance (SVR). It occurs in up to 25% of patients undergoing cardiac surgery with cardiopulmonary bypass, can last up to 72 h, and is associated with a high mortality rate. MTB has been found to increase SVR and decrease vasopressor requirements in vasoplegic syndrome by inhibiting nitric oxide synthase, thus limiting the generation of nitric oxide, while inhibiting activation of soluble guanylyl cyclase and preventing vasodilation. MTB has been used in postgraft reperfusion during liver transplantation and anaphylaxis in a limited number of cases. Additionally, this medication has been used in septic shock with promising results, but similar to the cardiac surgical population, the effects of MTB administration on clinical outcomes has yet to be elucidated. SUMMARY: MTB should be considered during vasoplegic syndrome in cardiac surgery with cardiopulmonary bypass and usage may be more effective in an early critical window, prior to end-organ hypoperfusion. Other perioperative scenarios of MTB use show promise, but additional studies are required to develop formative conclusions.

Long-term outcomes and management of the heart transplant recipient.

Cardiac transplantation remains the gold standard in the treatment of advanced heart failure. With advances in immunosuppression, long-term outcomes continue to improve despite older and higher risk recipients. The median survival of the adult after heart transplantation is currently 10.7 years. While early graft failure and multiorgan system dysfunction are the most important causes of early mortality, malignancy, rejection, infection, and cardiac allograft vasculopathy contribute to late mortality. Chronic renal dysfunction is common after heart transplantation and occurs in up to 68% of patients by year 10, with 6.2% of patients requiring dialysis and 3.7% undergoing renal transplant. Functional outcomes after heart transplantation remain an area for improvement, with only 26% of patients working at 1-year post-transplantation, and are likely related to the high incidence of depression after cardiac transplantation. Areas of future research include understanding and managing primary graft dysfunction and reducing immunosuppression-related complications.

Use of Adjuncts Reduces Cardiopulmonary Bypass Time During Minimally Invasive Aortic Valve Replacement.

BACKGROUND: Minimally invasive aortic valve replacement (MIAVR) through a mini-thoracotomy is comparable to AVR through a sternotomy, but may have increased surgical times. The development of adjuncts such as the automatic knot fastener and percutaneous coronary sinus (CS) catheter may reduce this disadvantage. METHODS: A retrospective review conducted between 2002 and 2015 at a single institution revealed 78 patients who underwent MIAVR with adjuncts. The automatic knot fastener was used on all patients, and a successful CS catheter was placed and confirmed by echocardiography in 67 patients (86%). Patients were propensity matched against those who had MIAVR without adjuncts (n = 78) and through a median sternotomy (n = 78) for assessment of major morbidity. Variables were compared using an unpaired t-test, Wilcoxon rank sum test, chi-squared and Fisher's exact test where appropriate. RESULTS: Patients who underwent MIAVR with adjuncts had shorter cross-clamp times (70.5 versus 108.1 and 84.4 min; p <0.0001) and cardiopulmonary bypass (CPB) times (101.1 versus 166.12 and 127.7 min; p <0.0001) than those who underwent MIAVR without adjuncts or through a median sternotomy. Patients who underwent MIAVR received fewer blood transfusions compared to those undergoing AVR via a median sternotomy (0.6 and 1.2 versus 2.5; p <0.012). Patients who underwent MIAVR with adjuncts had similar rates of new-onset atrial fibrillation (AF) than those undergoing MIAVR without adjuncts (33% versus 22%; p = 0.11), but had higher rates of AF compared to the sternotomy group (33% versus 17%; p = 0.02). Rates of in-hospital morbidity and mortality were similar between all groups. CONCLUSIONS: The use of adjuncts during MIAVR led to a significant shortening of cross-clamp and CPB times, and to a requirement for fewer blood transfusions. Morbidity and mortality rates after MIAVR were similar to those in patients undergoing a median sternotomy.

Mitral Regurgitation After Orthotopic Lung Transplantation: Natural History and Impact on Outcomes.

OBJECTIVE: Progression of mitral regurgitation (MR) after orthotopic lung transplantation (OLT) may be an underrecognized phenomenon due to the overlapping symptomatology of pulmonary and valvular disease. Literature evaluating the progression of MR after OLT currently is limited to case reports. Therefore, the hypothesis that MR progresses after OLT was tested and the association of preprocedure MR with postoperative mortality was assessed. DESIGN: A retrospective cohort. SETTING: A tertiary-care hospital. PARTICIPANTS: Patients who underwent OLT between January 1, 2003 and February 4, 2012. INTERVENTIONS: After receiving institutional review board approval, a preprocedure transesophageal echocardiogram was compared with a postoperative transthoracic echocardiogram (TTE) to determine the progression of MR. Univariate and multivariate association between preprocedure MR grade and 1- and 5-year mortality was assessed. A p value of<0.05 was considered statistically significant. MEASUREMENTS AND MAIN RESULTS: From 715 patients who underwent OLT, 352 had a postoperative TTE and were included in the evaluation of progression of MR. Five patients had progression of MR postoperatively, and the mean change in MR score of -0.04 was found to be nonsignificant (p = 0.25). Mortality data were available for 634 of the 715 patients. After covariate adjustment, there was no significant association between MR grade and 1-year mortality (p = 0.20) or 5-year mortality (p = 0.46). CONCLUSIONS: This study rejected the hypothesis that primary and secondary MR progresses after OLT and found that preprocedure MR was not associated with increased postoperative mortality. Despite the findings that MR does not progress in all patients, there is a subset of patients for whom MR progression is clinically significant.