Sternal bone anatomy on preoperative imaging as an independent predictor of deep sternal dehiscence following median sternotomy.

Complications following median sternotomy are associated with morbidity, mortality, and major healthcare costs. With plastic surgeons being increasingly consulted to close complex sternotomy wounds, a more accurate risk stratification tool for this comorbid patient population is warranted. This study examines the association of preoperative radiologic sternal measurements and deep sternal dehiscence, comparing this with other known clinical risk factors. A decreased manubrium sternal thickness relative to body weight (<0.13 mm/kg) and an absolute inferior sternal width ≤13.8 mm had a significant association with the development of deep sternal dehiscence, even with adjustment for known clinical risk factors. With such measurements assisting in further risk stratification, the opportunity to improve risk assessment holds value for plastic and reconstructive surgeons who are consulted to close extensive sternotomy wounds.

Novel use of interosseous absorbable mattress sutures for secondary sternal fixation: A case series.

There is currently no consensus on the treatment of median sternotomy patients presenting secondarily with deep sternal wound infection or symptomatic sternal nonunion. We have developed a novel approach to sternal bone fixation when concerns for open wounds or microbial colonization preclude the use of permanent hardware placement: (1) sternal closure with absorbable interosseous monocortical horizontal mattress sutures followed by (2) multilayered soft tissue closure with pectoralis major advancement or turnover flaps. Benefits of this technique include: closure of retrosternal dead-space, tension offloading of the soft tissue closure, repair of transverse sternal fractures, and preservation of internal mammary artery (IMA) perforators for potential pectoralis turnover flaps. In our early experience, this technique has been successful at promoting functional sternal union - even in secondary closure of high-risk patients contraindicated for permanent hardware placement.

Loss of Independent Living in Patients Undergoing Transcatheter or Surgical Aortic Valve Replacement: A Retrospective Cohort Study.

BACKGROUND: The recommendation for transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) in patients 65 to 80 years of age is equivocal, leaving patients with a difficult decision. We evaluated whether TAVR compared to SAVR is associated with reduced odds for loss of independent living in patients ≤65, 66 to 79, and ≥80 years of age. Further, we explored mechanisms of the association of TAVR and adverse discharge. METHODS: Adult patients undergoing TAVR or SAVR within a large academic medical system who lived independently before the procedure were included. A multivariable logistic regression model, adjusting for a priori defined confounders including patient demographics, preoperative comorbidities, and a risk score for adverse discharge after cardiac surgery, was used to assess the primary association. We tested the interaction of patient age with the association between aortic valve replacement (AVR) procedure and loss of independent living. We further assessed whether the primary association was mediated (ie, percentage of the association that can be attributed to the mediator) by the procedural duration as prespecified mediator. RESULTS: A total of 1751 patients (age median [quartiles; min-max], 76 [67, 84; 23-100]; sex, 56% female) were included. A total of 27% (222/812) of these patients undergoing SAVR and 20% (188/939) undergoing TAVR lost the ability to live independently. In our cohort, TAVR was associated with reduced odds for loss of independent living compared to SAVR (adjusted odds ratio [OR adj ] 0.19 [95% confidence interval {CI}, 0.14-0.26]; P < .001). This association was attenuated in patients ≤65 years of age (OR adj 0.63 [0.26-1.56]; P = .32) and between 66 and 79 years of age (OR adj 0.23 [0.15-0.35]; P < .001), and magnified in patients ≥80 years of age (OR adj 0.16 [0.10-0.25]; P < .001; P -for-interaction = .004). Among those >65 years of age, a shorter procedural duration mediated 50% (95% CI, 28-76; P < .001) of the beneficial association of TAVR and independent living. CONCLUSIONS: Patients >65 years of age undergoing TAVR compared to SAVR had reduced odds for loss of independent living. This association was partly mediated by shorter procedural duration. No association between AVR approach and the primary end point was found in patients ≤65 years of age.

Timing of Blood Transfusions and 30-Day Patient Outcomes After Coronary Artery Bypass Graft Surgery.

OBJECTIVE: Packed red blood cell transfusion during coronary artery bypass graft surgery is known to be associated with adverse outcomes. However, the association of the timing between transfusions in relation to discharge and 30-day postoperative outcomes has not been studied. The study authors investigated the impact of transfusion timing on 30-day surgical outcomes. DESIGN: A retrospective review. SETTING: At a single tertiary-care academic hospital. PARTICIPANTS: A total of 2,481 adult patients underwent primary coronary artery bypass graft surgery between January 2014 and December 2020. MEASUREMENTS AND MAIN RESULTS: The relationship between the timing of packed red blood cell transfusion (intraoperative, postoperative, or both) and 30-day postoperative outcome variables was calculated as an odds ratio. The influence of timing of transfusion on adjusted probability of postoperative complications was plotted against the lowest intraoperative hematocrit. The median age of the population was 67 years (60.0-74.0), body mass index was 28.5 (25.6-32.3) kg/m2, and 497 (20.0%) were female. A total of 1,588 (36%) patients received packed red blood cell transfusions; 182 (7.3%) received intraoperative transfusions, 489 (19.7%) received postoperative transfusions, and 222 (9.0%) received both (intraoperative and postoperative transfusions). Postoperative transfusion was associated with significantly higher odds of readmission (1.83 [1.32-2.54], p = 0.002) and heart failure (1.64 [1.2-2.23], p = 0.008) compared to patients with no transfusions; whereas intraoperative transfusions were not. CONCLUSION: The authors' data suggested that the postoperative timing of transfusion in patients undergoing coronary artery bypass graft surgery may be associated with an increased incidence of 30-day heart failure and readmission. Prospective research is needed to conclusively confirm these findings.

Geometric Indices for Predicting Ischemic Mitral Regurgitation: Correlation of Mitral Valve Coaptation Area With Tenting Height, Tenting Area and Tenting Volume.

OBJECTIVES: Ischemic remodeling of the left ventricle in patients with coronary artery disease (CAD) results in geometric changes of the mitral valve (MV) apparatus, leading to reduced MV leaflet coaptation. Although the calculation of the coaptation area has value in assessing the effects of left ventricular remodeling on the MV, it is difficult and time-consuming to measure. In this study the authors hypothesized that the tenting volume (TV) would have a greater association with coaptation area than tenting height (TH) or tenting area (TA). DESIGN: A retrospective review. SETTING: A single tertiary-care academic hospital. PARTICIPANTS: There were 145 adult patients who underwent coronary artery bypass graft surgery between April 2018 and July 2020. MEASUREMENTS AND MAIN RESULTS: Intraoperative 2- and 3-dimensional transesophageal echocardiographic studies were obtained in the precardiopulmonary bypass period. Offline analysis was used to obtain TH, TA, TV and coaptation area for each patient. Correlation between the coaptation area and the TH, TA, and TV was conducted using Pearson's correlation. The median age of the population was 68.0 years (61.0-73.3), the body mass index was 29.0 kg/m2 (25.7-33.5), and 17.8% were females. Increases in TV were the most reliable predictor of decreases in coaptation area (R2 = 0.75) followed by TA (R2 = 0.48) and TH (R2 = 0.47). CONCLUSION: As a representative of the complete topography of the MV, the authors' study demonstrated that in patients with CAD, TV has a greater negative correlation with coaptation area as compared to TH or TA.

Development of a risk score to predict occurrence of deep sternal dehiscence requiring operative debridement.

OBJECTIVE: Severe deep sternal wound (DSW) complications after cardiac surgery are a source of cost, morbidity, and mortality. Our objective was to develop and validate a clinical risk score for predicting risk of DSW requiring operative bone debridement, the most severe form of sternal dehiscence. METHODS: A retrospective review was conducted of patients who underwent open cardiac surgery at a single institution between October 2007 and March 2019. Primary outcome was DSW requiring sternal bone debridement. Potential risk factors were screened using Least Absolute Shrinkage and Selection Operator (LASSO) and significant covariates were included in a logistic regression prediction model. Interval validation was performed using 10-fold cross-validation. A novel sternal wound dehiscence risk score was derived from the relative parameterization estimates. RESULTS: One hundred thirty-four of 8403 patients (1.6%) were identified as having a DSW. Female sex (odds ratio [OR], 2.75; 95% CI, 2.58-2.93), body mass index (OR, 1.0946; 95% CI, 1.09-1.09), percent glycated hemoglobin (OR, 1.31; 95% CI, 1.28-1.33), peripheral vascular disease (OR, 2.38; 95% CI, 2.2005-2.5752), smoking (OR, 1.66; 95% CI, 1.53-1.79) and elevated creatinine level (OR, 1.20; 95% CI, 1.18-1.22) were independent predictors of DSW. Patients were categorized as minimal risk (0%-1%), low risk (2%-3%), intermediate risk (4%-7%), and high risk (9%-64.0%) on the basis of risk score. CONCLUSIONS: This risk stratification model for DSW requiring operative debridement might provide individualized estimates of risk, and guide counseling and potential risk mitigation strategies.

Intraoperative Oxygen Practices in Cardiac Surgery: A National Survey.

OBJECTIVE: To describe the current nationwide perspectives and practice regarding intraoperative oxygen titration in cardiac surgery. DESIGN: Prospective, observational survey. SETTING: Hospitals across the United States. PARTICIPANTS: Cardiovascular anesthesiologists and perfusionists. INTERVENTIONS: Expert- and consensus-derived electronic surveys were sent to perfusionists and cardiac anesthesiologists to evaluate the current intraoperative practices around oxygen administration. Providers were asked about individual intraoperative oxygen titration practices used at different stages of cardiac surgical procedures. Anonymous responses were collected in the Research Electronic Data Capture (REDCap). MEASUREMENTS AND MAIN RESULTS: A total of 3,335 providers were invited to participate, of whom 554 (317 anesthesiologists and 237 perfusionists) were included in the final analysis (17% response rate). During cardiopulmonary bypass (CPB), perfusionists reported a median (interquartile range [IQR]) target range from 150 (110-220)-to-325 mmHg (250-400), while anesthesiologists reported a significantly lower target range from 90 (70-150)-to-250 mmHg (158-400) (p values <0.0001 and 0.02, respectively). This difference was most pronounced at lower partial pressure of arterial oxygen (PaO2) ranges. The median PaO2 considered "too low" by perfusionists was 100 mmHg (IQR 80-125), whereas it was 60 mmHg (IQR 60-75) for anesthesiologists, who reported for both off and on bypass. The median PaO2 considered "too high" was 375 mmHg (IQR 300-400) for perfusionists and 300 mmHg (IQR 200-400) for anesthesiologists. Anesthesiologists, therefore, reported more comfort with significantly lower PaO2 values (p < 0.0001), and considered a higher PaO2 value less desirable compared with perfusionists (p < 0.0001). CONCLUSIONS: This survey demonstrated there was wide variation in oxygen administration practices between perfusionists and anesthesiologists. Hyperoxygenation was more common while on CPB.

An Algorithmic Approach to the Surgical Management of Sternal Dehiscence: A Single-Center Experience.

BACKGROUND: Deep sternal wound complications following sternotomy represent a complex challenge. Management can involve debridement, flap reconstruction, and rigid sternal fixation (RSF). We present our 11-year experience in the surgical treatment of deep sternal wound dehiscence using a standardized treatment algorithm. METHODS: A retrospective review was conducted of all 134 cardiac patients who required operative debridement after median sternotomy at a single institution between October 2007 and March 2019. Demographics, perioperative covariates, and outcomes were recorded. Univariate and subgroup analyses were performed. RESULTS: One-hundred twelve patients (83.5%) with a deep sternal dehiscence underwent flap closure and 56 (50%) RSF. Of the patients who underwent flap closure, 87.5% received pectoralis advancement flaps. A 30-day mortality following reconstruction was 3.9%. Median length of stay after initial debridement was 8 days (interquartile range: 5-15). Of patients with flaps, 54 (48%) required multiple debridements prior to closure, and 30 (27%) underwent reoperation after flap closure. Patients who needed only a single debridement were significantly less likely to have a complication requiring reoperation (N = 10/58 vs. 20/54, 17 vs. 37%, p = 0.02), undergo a second flap (N = 6/58 vs. 17/54, 10 vs. 32%, p < 0.001), or, if plated, require removal of sternal plates (N = 6/34 vs. 11/22, 18 vs. 50%, p = 0.02). CONCLUSION: Although sternal dehiscence remains a complex challenge, an aggressive treatment algorithm, including debridement, flap closure, and consideration of RSF, can achieve good long-term outcomes. In low-risk patients, RSF does not appear to increase the likelihood of reoperation. We hypothesize that earlier surgical intervention, before the development of systemic symptoms, may be associated with improved outcomes.

Pembrolizumab Improves Survival After Resection of Intracardiac Metastatic Cervical Carcinoma.

Intracardiac metastasis of cervical squamous cell carcinoma (C-SCC) is rare, with historically poor long-term survival. We report the case of a 55-year-old woman with prior metastatic C-SCC who was found to have a right ventricular mass causing functional pulmonic stenosis and multiple pulmonary emboli 19 months after her initial diagnosis. She underwent surgical resection to prevent further embolization and heart failure. Pathology confirmed metastatic C-SCC and she was maintained on adjuvant pembrolizumab. She remained well 32 months later without further disease progression. Surgical resection of intracardiac metastasis of C-SCC combined with pembrolizumab therapy may result in improved postoperative life expectancy.

Carbon monoxide and a change of heart.

The relationship between carbon monoxide and the heart has been extensively studied in both clinical and preclinical settings. The Food and Drug Administration (FDA) is keenly focused on the ill effects of carbon monoxide on the heart when presented with proposals for clinical trials to evaluate efficacy of this gasotransmitter in a various disease settings. This review provides an overview of the rationale that examines the actions of the FDA when considering clinical testing of CO, and contrast that with the continued accumulation of data that clearly show not only that CO can be used safely, but is potently cardioprotective in clinically relevant small and large animal models. Data emerging from Phase I and Phase II clinical trials argues against CO being dangerous to the heart and thus it needs to be redefined and evaluated as any other substance being proposed for use in humans. More than twenty years ago, the belief that CO could be used as a salutary molecule was ridiculed by experts in physiology and medicine. Like all agents designed for use in humans, careful pharmacology and safety are paramount, but continuing to hinder progress based on long-standing dogma in the absence of data is improper. Now, CO is being tested in multiple clinical trials using innovative delivery methods and has proven to be safe. The hope, based on compelling preclinical data, is that it will continue to be evaluated and ultimately approved as an effective therapeutic.

Update: Gender differences in CABG outcomes-Have we bridged the gap?

BACKGROUND: Appreciation of unique presentation, patterns and underlying pathophysiology of coronary artery disease in women has driven gender based risk stratification and risk reduction efforts over the last decade. Data regarding whether these advances have resulted in unequivocal improvements in outcomes of CABG in women is conflicting. The objective of our study was to assess gender differences in post-operative outcomes following CABG. METHODS: Retrospective analyses of institutional data housed in the Society of Thoracic Surgeons (STS) database for patients undergoing CABG between 2002 and 2020 were conducted. Multivariable regression analysis was conducted to investigate gender differences in post-operative outcomes. P-values were adjusted using Bonferroni correction to reduce type-I errors. RESULTS: Our final cohort of 6,250 patients had fewer women than men (1,339 vs. 4,911). more women were diabetic (52.0% vs. 41.2%, p<0.001) and hypertensive (89.1% vs. 84.0%, p<0.001). Women had higher adjusted odds of developing ventilator dependence >48 hours (OR: 1.65 [1.21, 2.45], p = 0.002) and cardiac readmissions (OR: 1.56 [1.27, 2.30], p = 0.003). After adjustment for comorbidity burden, mortality rates in women were comparable to those of age-matched men. CONCLUSION: The findings of our study indicate that despite apparent reduction of differences in mortality, the burden of postoperative morbidity is still high among women.

An Unusual Cause of Functional Mitral Stenosis: A Left Atrial Intimal Sarcoma.

Primary cardiac tumors are rare, with an incidence of <0.1% in postmortem series; sarcomas comprise 75% of these. Cardiac sarcomas may be life-threatening at the time of presentation. We describe a left atrial intimal sarcoma presenting with constitutional symptoms, obstructive shock, and systemic emboli, and treated with proton beam therapy. (Level of Difficulty: Intermediate.).

A Case Report on Papillary Muscle Rupture Following Mitral Valve Replacement in the Setting of Previously Undiagnosed Amyloidosis.

This case describes a patient who underwent mitral valve replacement (MVR) surgery with preservation of the subvalvular apparatus who suffered anterolateral papillary muscle rupture (PMR) postseparation from cardiopulmonary bypass. This patient had no history of coronary artery disease (CAD); subsequent pathology of the papillary muscle showed evidence of amyloid deposition. Although most PMRs are caused by ischemia from CAD, cardiac amyloidosis must be considered in the absence of CAD and worked up appropriately as cardiac involvement of amyloidosis, especially the amyloid light-chain (AL) subtype, is prognostic of increased mortality that can be mitigated with therapy.

Intraoperative Oxygen Concentration and Neurocognition after Cardiac Surgery.

BACKGROUND: Despite evidence suggesting detrimental effects of perioperative hyperoxia, hyperoxygenation remains commonplace in cardiac surgery. Hyperoxygenation may increase oxidative damage and neuronal injury leading to potential differences in postoperative neurocognition. Therefore, this study tested the primary hypothesis that intraoperative normoxia, as compared to hyperoxia, reduces postoperative cognitive dysfunction in older patients having cardiac surgery. METHODS: A randomized double-blind trial was conducted in patients aged 65 yr or older having coronary artery bypass graft surgery with cardiopulmonary bypass. A total of 100 patients were randomized to one of two intraoperative oxygen delivery strategies. Normoxic patients (n = 50) received a minimum fraction of inspired oxygen of 0.35 to maintain a Pao2 above 70 mmHg before and after cardiopulmonary bypass and between 100 and 150 mmHg during cardiopulmonary bypass. Hyperoxic patients (n = 50) received a fraction of inspired oxygen of 1.0 throughout surgery, irrespective of Pao2 levels. The primary outcome was neurocognitive function measured on postoperative day 2 using the Telephonic Montreal Cognitive Assessment. Secondary outcomes included neurocognitive function at 1, 3, and 6 months, as well as postoperative delirium, mortality, and durations of mechanical ventilation, intensive care unit stay, and hospital stay. RESULTS: The median age was 71 yr (interquartile range, 68 to 75), and the median baseline neurocognitive score was 17 (16 to 19). The median intraoperative Pao2 was 309 (285 to 352) mmHg in the hyperoxia group and 153 (133 to 168) mmHg in the normoxia group (P < 0.001). The median Telephonic Montreal Cognitive Assessment score on postoperative day 2 was 18 (16 to 20) in the hyperoxia group and 18 (14 to 20) in the normoxia group (P = 0.42). Neurocognitive function at 1, 3, and 6 months, as well as secondary outcomes, were not statistically different between groups. CONCLUSIONS: In this randomized controlled trial, intraoperative normoxia did not reduce postoperative cognitive dysfunction when compared to intraoperative hyperoxia in older patients having cardiac surgery. Although the optimal intraoperative oxygenation strategy remains uncertain, the results indicate that intraoperative hyperoxia does not worsen postoperative cognition after cardiac surgery.

Cardiopulmonary Bypass Suppresses Forkhead Box O3 and Downstream Autophagy in the Diabetic Human Heart.

BACKGROUND: Autophagy is an integral component of cellular homeostasis and metabolism. The exact mechanism of impaired autophagy in diabetes mellitus is unknown. Forkhead Box O3 (FOXO3α) is a key regulator of oxidative stress-related responses. We hypothesize FOXO3α is a direct upstream regulator of the autophagy pathway, and its upregulation is compromised in diabetic patients during stress of cardiopulmonary bypass (CPB). METHODS: The study enrolled 32 diabetic and 33 nondiabetic patients undergoing a cardiac surgical procedure on CPB. Right atrial tissue and serum samples were collected before and after CPB per protocol. A set of key components were quantitatively assessed and compared by microarray, immunoblotting, and immunohistochemistry studies. Data were analyzed using paired or unpaired student test. A P of <.05 or less was considered significant. RESULTS: Serum microarray showed FOXO3α was upregulated in the diabetic vs nondiabetic group after CPB (P = .033), autophagy-related 4B gene and Beclin 1 gene were greatly upregulated in the nondiabetic group (P = .028 and P = .002, respectively). On immunoblotting, there was upregulation of FOXO3α in the nondiabetic patients after CPB (P = .003). There were increased levels of Beclin-1, Bcl-2, and light chain 3B after CPB in the nondiabetic group only (P = .016, P = .005, P = .002, respectively). Sirtuin 1, Unc-51-like autophagy activating kinase 1 (ULK1), peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α), and mammalian target of rapamycin (mTOR) were not significantly changed in the nondiabetic group after CPB. CONCLUSIONS: Compared with nondiabetic patients, there was no significant upregulation of FOXO3α in diabetic patients, which could possibly explain the lack of upregulation of the autophagy process after CPB. FOXO3α could potentially serve as a therapeutic target to improve cellular homeostasis.

Changes in Care for Acute Pulmonary Embolism Through A Multidisciplinary Pulmonary Embolism Response Team.

BACKGROUND: Optimal management of acute pulmonary embolism requires expertise offered by multiple subspecialties. As such, pulmonary embolism response teams (PERTs) have increased in prevalence, but the institutional consequences of a PERT are unclear. METHODS: We compared all patients that presented to our institution with an acute pulmonary embolism in the 3 years prior to and 3 years after the formation of our PERT. The primary outcome was in-hospital pulmonary embolism-related mortality before and after the formation of the PERT. Sub-analyses were performed among patients with elevated-risk pulmonary embolism. RESULTS: Between August 2012 and August 2018, 2042 patients were hospitalized at our institution with acute pulmonary embolism, 884 (41.3%) pre-PERT implementation and 1158 (56.7%) post-PERT implementation, of which 165 (14.2%) were evaluated by the PERT. There was no difference in pulmonary embolism-related mortality between the two time periods (2.6% pre-PERT implementation vs 2.9% post-PERT implementation, P = .89). There was increased risk stratification assessment by measurement of cardiac biomarkers and echocardiograms post-PERT implementation. Overall utilization of advanced therapy was similar between groups (5.4% pre-PERT implementation vs 5.4% post-PERT implementation, P = 1.0), with decreased use of systemic thrombolysis (3.8% pre-PERT implementation vs 2.1% post-PERT implementation, P = 0.02) and increased catheter-directed therapy (1.3% pre-PERT implementation vs 3.3% post-PERT implementation, P = 0.05) post-PERT implementation. Inferior vena cava filter use decreased after PERT implementation (10.7% pre-PERT implementation vs 6.9% post-PERT implementation, P = 0.002). Findings were similar when analyzing elevated-risk patients. CONCLUSION: Pulmonary embolism response teams may increase risk stratification assessment and alter application of advanced therapies, but a mortality benefit was not identified.

A High Doppler Gradient: Obstruction or No Obstruction?: A Case Report.

The angle correction feature in ultrasound systems is used when there is difficulty accurately aligning the Doppler beam with the flow to be interrogated. The operator can manually "correct" the angle to the actual direction of flow. Subsequently, the machine corrects the peak velocity for the angle. We present a case of aortic valve replacement (AVR) in which falsely high transaortic gradients were obtained immediately after separation from cardiopulmonary bypass (CPB). We recommend that there be a more prominent notification when the angle correction feature is used with machine prompts confirming when a peak velocity is obtained using angle correction.

Decreased PGC-1α Post-Cardiopulmonary Bypass Leads to Impaired Oxidative Stress in Diabetic Patients.

BACKGROUND: The mechanism of mitochondrial dysfunction after cardiopulmonary bypass (CPB) in patients with diabetes mellitus lacks understanding. We hypothesized that impaired beta-oxidation of fatty acids leads to worsened stress response in this patient population after cardiac surgery. METHODS: After Institutional Review Board approval, right atrial tissue samples were collected from 35 diabetic patients and 33 nondiabetic patients before and after CPB. Patients with glycated hemoglobin of 6.0 or greater and a clinical diagnosis of diabetes mellitus were considered to be diabetic. Immunoblotting and microarray analysis were performed to assess protein and gene expression changes. Blots were quantified with ImageJ and analyzed using one-way analysis of variance with multiple Student's t test comparisons after normalization. All p values less than 0.05 were considered significant. Immunohistochemistry was performed for cellular lipid deposition assessment. RESULTS: Diabetic patients had significantly lower levels of PGC-1α before and after CPB (p < 0.01 for both) compared with nondiabetic patients. Several upstream regulators of PGC-1α (SIRT1 and CREB) were significantly higher in nondiabetic patients before CPB (p = 0.01 and 0.0018, respectively). Antioxidant markers (NOX4 and GPX4), angiogenic factors (TGF-ß, NT3, and Ang1), and the antiapoptotic factor BCL-xL were significantly lower in diabetic patients after CPB (p < 0.05). The expression of genes supporting mitochondrial energy production (CREB5 and SLC25A40) and angiogenic genes (p < 0.05) was significantly downregulated in diabetic patients after CPB. Immunohistochemistry results showed significantly increased lipid deposition in diabetic myocardial tissue. CONCLUSIONS: Decreased PGC-1α in diabetic patients may lead to impaired mitochondrial function and attenuated antiapoptotic and angiogenic responses after CPB. Therefore, PGC-1α and upstream regulators could serve as a target for improving beta-oxidation in diabetic patients.

Prevalence and Outcomes of Isolated Tricuspid Valve Surgery Among Medicare Beneficiaries.

We sought to characterize the clinical outcomes and to identify predictors of mortality undergoing isolated tricuspid valve surgery in the United States. We identified 5,164 patients undergoing isolated tricuspid valve surgery from the Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review data between January 2003 and December 2014. The primary outcome was all cause 1-year mortality. A backward elimination method was performed to identify predictors of 1-year mortality. Tricuspid valve repair was performed in 2,494 (48.3%) patients and tricuspid valve replacement was performed in 2,670 (51.7%) patients. Perioperative and 1-year mortality rates were 9.9% and 24.1%, respectively. Predictors of 1-year mortality were age (p <0.001), chronic heart failure (p = 0.001, cirrhosis (p <0.001), carcinoid syndrome (p <0.001), chronic kidney disease (p = 0.001), secondary pulmonary hypertension (p = 0.023), endocarditis (p = 0.005), decubitus ulcer (p <0.001), malnutrition (p <0.001), replacement (p = 0.013), emergency procedure (p <0.001), and preprocedural shock (p <0.001). The C-statistic for 1-year mortality was 0.70 (95% confidence interval, 0.67 to 0.73). In conclusion, isolated tricuspid valve surgery is infrequently performed in the United States, and is associated with high 1-year mortality. Patients at higher risk for mortality can be identified based on the presence of a number of comorbidities at the time of surgery.