Sex bias in prediction and diagnosis of cardiac surgery associated acute kidney injury.

BACKGROUND: Female sex has been recognized as a risk factor for cardiac surgery associated acute kidney injury (CS-AKI). The current study sought to evaluate whether female sex is a risk factor for CS-AKI, or modifies the association of peri-operative change in serum creatinine with CS-AKI. METHODS: Observational study of adult patients undergoing cardiac surgery between 2000 and 2019 in a single U.S. center. The main variable of interest was registered patient sex, identified from electronic medical records. The main outcome was CS-AKI within 2 weeks of surgery. RESULTS: Of 58526 patients, 19353 (33%) were female; 12934 (22%) incurred AKI based on ≥ 0.3 mg/dL or ≥ 50% rise in serum creatinine (any AKI), 3320 (5.7%) had moderate to severe AKI, and 1018 (1.7%) required dialysis within 2 weeks of surgery. Female sex was associated with higher risk for AKI in models that were based on preoperative serum creatinine (OR, 1.35; 95% CI, 1.29-1.42), and lower risk with the use of estimated glomerular filtration, (OR, 0.90; 95% CI, 0.86-0.95). The risk for moderate to severe CS-AKI for a given immediate peri-operative change in serum creatinine was higher in female compared to male patients (p < .0001 and p < .0001 for non-linearity), and the association was modified by pre-operative kidney function (p < .0001 for interaction). CONCLUSIONS: The association of patient sex with CS-AKI and its direction was dependent on the operational definition of pre-operative kidney function, and differential outcome misclassification due to AKI defined by absolute change in serum creatinine.

Ninety-Day Risk-Standardized Home Time as a Performance Metric for Cardiac Surgery Hospitals in the United States.

BACKGROUND: Assessing hospital performance for cardiac surgery necessitates consistent and valid care quality metrics. The association of hospital-level risk-standardized home time for cardiac surgeries with other performance metrics such as mortality rate, readmission rate, and annual surgical volume has not been evaluated previously. METHODS: The study included Medicare beneficiaries who underwent isolated or concomitant coronary artery bypass graft, aortic valve, or mitral valve surgery from January 1, 2013, to October 1, 2019. Hospital-level performance metrics of annual surgical volume, 90-day risk-standardized mortality rate, 90-day risk-standardized readmission rate, and 90-day risk-standardized home time were estimated starting from the day of surgery using generalized linear mixed models with a random intercept for the hospital. Correlations between the performance metrics were assessed using the Pearson correlation coefficient. Patient-level clinical outcomes were also compared across hospital quartiles by 90-day risk-standardized home time. Last, the temporal stability of performance metrics for each hospital during the study years was also assessed. RESULTS: Overall, 919 698 patients (age 74.2±5.8 years, 32% women) were included from 1179 hospitals. Median 90-day risk-standardized home time was 71.2 days (25th-75th percentile, 66.5-75.6), 90-day risk-standardized readmission rate was 26.0% (19.5%-35.7%), and 90-day risk-standardized mortality rate was 6.0% (4.0%-8.8%). Across 90-day home time quartiles, a graded decline was observed in the rates of in-hospital, 90-day, and 1-year mortality, and 90-day and 1-year readmission. Ninety-day home time had a significant positive correlation with annual surgical volume (r=0.31; P<0.001) and inverse correlation with 90-day risk-standardized readmission rate (r=-0.40; P <0.001) and 90-day risk-standardized mortality rate (r=-0.60; P <0.001). Use of 90-day home time as a performance metric resulted in a meaningful reclassification in performance ranking of 22.8% hospitals compared with annual surgical volume, 11.6% compared with 90-day risk-standardized mortality rate, and 19.9% compared with 90-day risk-standardized readmission rate. Across the 7 years of the study period, 90-day home time demonstrated the most temporal stability of the hospital performance metrics. CONCLUSIONS: Ninety-day risk-standardized home time is a feasible, comprehensive, patient-centered metric to assess hospital-level performance in cardiac surgery with greater temporal stability than mortality and readmission measures.

Comparison of risk scores for predicting outcomes after isolated tricuspid valve surgery.

BACKGROUND: Risk models play important roles in stratification and decision-making towards cardiac surgery. Isolated tricuspid valve surgery is a high risk but increasingly performed the operation, however, the performance of risk models has not been externally evaluated in these patients. We compared the prognostic utility of contemporary risk scores for isolated tricuspid valve surgery. METHODS: Consecutive patients undergoing isolated tricuspid valve surgery at Cleveland Clinic during 2004-2018 were evaluated in this cohort study. EuroSCORE II, Society of Thoracic Surgeon's tricuspid (STS-TVS) score, and the Model for End-stage Liver Disease (MELD) score were retrospectively calculated, and their performance for predicting operative mortality, postoperative complications, and mortality during follow-up was assessed. RESULTS: Amongst 207 patients studied, the mean age was 54.1 ± 17.9 years, 116 (56.0%) were female, 92 (44.4%) had secondary tricuspid regurgitation, and 151 (72.9%) had a surgical repair. Mean EuroSCORE II, STS-TVS, and MELD scores were 6.3 ± 6.6%, 5.5 ± 6.2%, and 9.8 ± 4.7, respectively. C-statistics (95% confidence intervals) for operative mortality were 0.83 (0.74-0.93) for EuroSCORE II, 0.60 (0.45-0.75) for STS-TVS score, and 0.74 (0.58-0.89) for MELD score, while observed/expected ratios were 0.78 and 0.89 for the first two scores. All three scores were associated with mortality during follow-up and discriminated most postoperative complications. CONCLUSION: EuroSCORE II was superior to STS-tricuspid score for isolated TVS risk assessment. Although surgical risk scores traditionally underestimated operative mortality after isolated tricuspid valve surgery, they did not in our cohort, reflecting the excellent surgical results. The simple MELD score performed similarly to the EuroSCORE II, especially for discriminating morbidities.

Atrial fibrillation rhythm is associated with marked changes in metabolic and myofibrillar protein expression in left atrial appendage.

Atrial fibrillation (AF) is strongly associated with risk of stroke and heart failure. AF promotes atrial remodeling that increases risk of stroke due to left atrial thrombogenesis, and increases energy demand to support high rate electrical activity and muscle contraction. While many transcriptomic studies have assessed AF-related changes in mRNA abundance, fewer studies have assessed proteomic changes. We performed a proteomic analysis on left atrial appendage (LAA) tissues from 12 patients with a history of AF undergoing elective surgery; atrial rhythm was documented at time of surgery. Proteomic analysis was performed using liquid chromatography with mass spectrometry (LC/MS-MS). Data-dependent analysis identified 3090 unique proteins, with 408 differentially expressed between sinus rhythm and AF. Ingenuity Pathway Analysis of differentially expressed proteins identified mitochondrial dysfunction, oxidative phosphorylation, and sirtuin signaling among the most affected pathways. Increased abundance of electron transport chain (ETC) proteins in AF was accompanied by decreased expression of ETC complex assembly factors, tricarboxylic acid cycle proteins, and other key metabolic modulators. Discordant changes were also evident in the contractile unit with both up and downregulation of key components. Similar pathways were affected in a comparison of patients with a history of persistent vs. paroxysmal AF, presenting for surgery in sinus rhythm. Together, these data suggest that while the LAA attempts to meet the energetic demands of AF, an uncoordinated response may reduce ATP availability, contribute to tissue contractile and electrophysiologic heterogeneity, and promote a progression of AF from paroxysmal episodes to development of a substrate amenable to persistent arrhythmia.

Intercostal Blocks with Liposomal Bupivacaine in Thoracic Surgery: A Retrospective Cohort Study.

OBJECTIVE: Assess the efficacy of adding liposomal bupivacaine (LB) to bupivacaine-containing intercostal nerve blocks (ICNBs) to improve analgesia and decrease opioid consumption and hospital length of stay compared with bupivacaine-only ICNBs. DESIGN: This retrospective, observational investigation compared pain intensity scores and cumulative opioid consumption within the first 72 postoperative hours in patients who received ICNBs with bupivacaine plus LB (LB group) versus bupivacaine only (control group) after minimally invasive anatomic pulmonary resection. LB was tested for noninferiority on pain scores and opioid consumption. If LB was noninferior, superiority of LB was tested on both outcomes. SETTING: Academic tertiary care medical center. PARTICIPANTS: Adult patients undergoing minimally invasive anatomic pulmonary resection. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: For the secondary analysis, hospital length of stay was compared through the Cox regression model. Of 396 patients, 178 (45%) received LB and 218 (55%) did not. The mean (standard deviation) pain score was three (one) in the LB group and three (one) in the control group, with a difference of -0.10 (97.5% confidence interval [-0.39 to 0.18]; p = 0.41). The mean (standard deviation) cumulative opioid consumption (intravenous morphine equivalents) was 198 (208) mg in the LB group and 195 (162) mg in the control group. Treatment effect in opioid consumption was estimated at a ratio of geometric mean of 0.94 (97.5% confidence interval [0.74-1.20]; p = 0.56). Pain control and opioid consumption were noninferior with LB but not superior. Hospital discharge was not different between groups. CONCLUSIONS: LB with bupivacaine in ICNBs did not demonstrate superior postoperative analgesia or affect the rate of hospital discharge.

Techniques for Mitral Valve Re-repair.

The emergence of mitral valve repair as the preferred treatment for severe mitral regurgitation (MR) caused by degenerative disease has been accompanied by an increasing number of valve repair failures seen by surgeons. Consequently, the feasibility of valve re-repair vs valve replacement at the time of reoperation has become a valid clinical consideration. In this report we explore the mechanisms of mitral valve repair failure as well as factors that meaningfully influence the likelihood of a successful re-repair. We provide illustrations of techniques for re-repair that we have used with reliable success, informed by the mechanism of repair failure. Lastly, we share our outcomes for mitral valve re-repair over the last 5 years and discuss our experience using the techniques illustrated in this report.

Early failure after non-resectional mitral valve repair with artificial chordae.

Severe recurrent mitral regurgitation within 1 year of mitral valve repair is usually attributed to a technical issue with the original repair procedure. However, when artificial chordae are employed to correct mitral valve prolapse, ventricular remodeling (ie, decreased ventricular size) can lead to recurrent prolapse and valve dysfunction. To illustrate this phenomenon, we present two patients who experienced early failure after undergoing mitral valve repair with artificial chordae.

Primary isolated CABG restrictive blood transfusion protocol reduces transfusions and length of stay.

BACKGROUND: Cardiac surgery accounts for 10-15% of blood transfusions in the US, despite benefits and calls of limiting its use. We sought to evaluate the impact of a restrictive transfusion protocol on blood use and clinical outcomes in patients undergoing isolated primary coronary artery bypass grafting (CABG). METHODS: Blood conservation measures, instituted in 2012, include preoperative optimization, intraoperative anesthesia, and pump fluid restriction with retrograde autologous priming and vacuum-assisted drainage, use of aminocaproic acid and cell saver, intra- and postoperative permissive anemia, and administration of iron and low-dose vasopressors if needed. Medical records of patients who underwent isolated primary CABG from 2009 to 2012 (group A; n = 375) and 2013 to 2016 (group B; n = 322) were compared. RESULTS: CABG with grafting to three or four coronary arteries was performed in 262 (70%) and 222 (69%) patients and bilateral internal thoracic artery grafting in 202 (54%) and 196 (61%) patients in groups A and B, respectively. Mean preoperative and intraoperative hematocrit was 40.3% and 40.7%, 28.9% and 29.4% in groups A and B, respectively. Total blood transfusion was 24% and 6.5%, intraoperative transfusion 11% and 1.2%, and postoperative transfusion 20% and 5.6% (P < .0001 for all) in groups A and B, respectively. Median postoperative length of stay was 5.0 days in group A and 4.5 days in group B (P = .02), with no significant differences in mortality or morbidity. CONCLUSIONS: A restrictive transfusion protocol reduced blood transfusions and postoperative length of stay without adversely affecting outcomes following isolated primary CABG.

Two-Year Outcomes of Surgical Treatment of Severe Ischemic Mitral Regurgitation.

BACKGROUND: In a randomized trial comparing mitral-valve repair with mitral-valve replacement in patients with severe ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI), survival, or adverse events at 1 year after surgery. However, patients in the repair group had significantly more recurrences of moderate or severe mitral regurgitation. We now report the 2-year outcomes of this trial. METHODS: We randomly assigned 251 patients to mitral-valve repair or replacement. Patients were followed for 2 years, and clinical and echocardiographic outcomes were assessed. RESULTS: Among surviving patients, the mean (±SD) 2-year LVESVI was 52.6±27.7 ml per square meter of body-surface area with mitral-valve repair and 60.6±39.0 ml per square meter with mitral-valve replacement (mean changes from baseline, -9.0 ml per square meter and -6.5 ml per square meter, respectively). Two-year mortality was 19.0% in the repair group and 23.2% in the replacement group (hazard ratio in the repair group, 0.79; 95% confidence interval, 0.46 to 1.35; P=0.39). The rank-based assessment of LVESVI at 2 years (incorporating deaths) showed no significant between-group difference (z score=-1.32, P=0.19). The rate of recurrence of moderate or severe mitral regurgitation over 2 years was higher in the repair group than in the replacement group (58.8% vs. 3.8%, P<0.001). There were no significant between-group differences in rates of serious adverse events and overall readmissions, but patients in the repair group had more serious adverse events related to heart failure (P=0.05) and cardiovascular readmissions (P=0.01). On the Minnesota Living with Heart Failure questionnaire, there was a trend toward greater improvement in the replacement group (P=0.07). CONCLUSIONS: In patients undergoing mitral-valve repair or replacement for severe ischemic mitral regurgitation, we observed no significant between-group difference in left ventricular reverse remodeling or survival at 2 years. Mitral regurgitation recurred more frequently in the repair group, resulting in more heart-failure-related adverse events and cardiovascular admissions. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00807040.).

Rate Control versus Rhythm Control for Atrial Fibrillation after Cardiac Surgery.

BACKGROUND: Atrial fibrillation after cardiac surgery is associated with increased rates of death, complications, and hospitalizations. In patients with postoperative atrial fibrillation who are in stable condition, the best initial treatment strategy--heart-rate control or rhythm control--remains controversial. METHODS: Patients with new-onset postoperative atrial fibrillation were randomly assigned to undergo either rate control or rhythm control. The primary end point was the total number of days of hospitalization within 60 days after randomization, as assessed by the Wilcoxon rank-sum test. RESULTS: Postoperative atrial fibrillation occurred in 695 of the 2109 patients (33.0%) who were enrolled preoperatively; of these patients, 523 underwent randomization. The total numbers of hospital days in the rate-control group and the rhythm-control group were similar (median, 5.1 days and 5.0 days, respectively; P=0.76). There were no significant between-group differences in the rates of death (P=0.64) or overall serious adverse events (24.8 per 100 patient-months in the rate-control group and 26.4 per 100 patient-months in the rhythm-control group, P=0.61), including thromboembolic and bleeding events. About 25% of the patients in each group deviated from the assigned therapy, mainly because of drug ineffectiveness (in the rate-control group) or amiodarone side effects or adverse drug reactions (in the rhythm-control group). At 60 days, 93.8% of the patients in the rate-control group and 97.9% of those in the rhythm-control group had had a stable heart rhythm without atrial fibrillation for the previous 30 days (P=0.02), and 84.2% and 86.9%, respectively, had been free from atrial fibrillation from discharge to 60 days (P=0.41). CONCLUSIONS: Strategies for rate control and rhythm control to treat postoperative atrial fibrillation were associated with equal numbers of days of hospitalization, similar complication rates, and similarly low rates of persistent atrial fibrillation 60 days after onset. Neither treatment strategy showed a net clinical advantage over the other. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT02132767.).

Two-Year Outcomes of Surgical Treatment of Moderate Ischemic Mitral Regurgitation.

BACKGROUND: In a trial comparing coronary-artery bypass grafting (CABG) alone with CABG plus mitral-valve repair in patients with moderate ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI) or survival after 1 year. Concomitant mitral-valve repair was associated with a reduced prevalence of moderate or severe mitral regurgitation, but patients had more adverse events. We now report 2-year outcomes. METHODS: We randomly assigned 301 patients to undergo either CABG alone or the combined procedure. Patients were followed for 2 years for clinical and echocardiographic outcomes. RESULTS: At 2 years, the mean (±SD) LVESVI was 41.2±20.0 ml per square meter of body-surface area in the CABG-alone group and 43.2±20.6 ml per square meter in the combined-procedure group (mean improvement over baseline, -14.1 ml per square meter and -14.6 ml per square meter, respectively). The rate of death was 10.6% in the CABG-alone group and 10.0% in the combined-procedure group (hazard ratio in the combined-procedure group, 0.90; 95% confidence interval, 0.45 to 1.83; P=0.78). There was no significant between-group difference in the rank-based assessment of the LVESVI (including death) at 2 years (z score, 0.38; P=0.71). The 2-year rate of moderate or severe residual mitral regurgitation was higher in the CABG-alone group than in the combined-procedure group (32.3% vs. 11.2%, P<0.001). Overall rates of hospital readmission and serious adverse events were similar in the two groups, but neurologic events and supraventricular arrhythmias remained more frequent in the combined-procedure group. CONCLUSIONS: In patients with moderate ischemic mitral regurgitation undergoing CABG, the addition of mitral-valve repair did not lead to significant differences in left ventricular reverse remodeling at 2 years. Mitral-valve repair provided a more durable correction of mitral regurgitation but did not significantly improve survival or reduce overall adverse events or readmissions and was associated with an early hazard of increased neurologic events and supraventricular arrhythmias. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00806988.).

Unrecognized Cardiac Amyloidosis at the Time of Mitral Valve Surgery: Incidence and Outcomes.

OBJECTIVE: It is increasingly recognized that cardiac amyloidosis can occur in patients with severe aortic stenosis undergoing both surgical and transcatheter valve replacements. We aimed to investigate whether unrecognized cardiac amyloidosis may also occur in patients with severe mitral valve disease undergoing surgery. METHODS: The pathology department database at our center was retrospectively analyzed over a 10-year period for cases in which the mitral valve or another type of cardiac tissue removed at the time of mitral surgery demonstrated incidental amyloidosis. Clinical and echocardiographic variables were collected from the electronic medical record and the echocardiographic database. RESULTS: Between 2007 and 2016, a total of 7,733 mitral valve surgical specimens were received. Of these, there were 15 cases in which the mitral valve, or another type of cardiac tissue removed at surgery, demonstrated incidentally detected amyloidosis. The most frequent comorbidities were hypertension (87%) and atrial fibrillation (80%); 13 patients (87%) underwent bioprosthetic mitral valve replacement, and 2 patients (13%) underwent mitral valve repair. Sites of amyloid deposition were the mitral valve (80%), left atrial appendage (33%), and subaortic tissue (7%); 14 patients (93%) had wild-type transthyretin amyloid. The mean duration of follow-up was 1,023 days (range: 29-2,811 days). There were no surgical complications in the follow-up period. CONCLUSIONS: Over a 10-year period, incidentally detected cardiac amyloidosis occurred in 0.2% of the mitral valve surgical cases. The outcomes for these patients undergoing mitral valve surgery were excellent, with no complications or deaths attributable to surgery at a mean follow-up of 1,023 days.

A Comparison of Global Longitudinal, Circumferential, and Radial Strain to Predict Outcomes After Cardiac Surgery.

OBJECTIVE: Myocardial strain measured by speckle-tracking echocardiography detects subtle regional and global left ventricular dysfunction. Myocardial strain is measured in the longitudinal, circumferential, and radial dimensions; however, it is unclear which dimension of strain is the best predictor of postoperative outcomes. DESIGN: A secondary analysis of prospectively collected data from a clinical trial (NCT01187329). SETTING: The cardiothoracic surgical operating rooms of an academic tertiary-care center. PARTICIPANTS: Cardiothoracic surgery patients with aortic stenosis having aortic valve replacement (AVR) with or without coronary artery bypass grafting enrolled in a clinical trial. INTERVENTIONS: Myocardial deformation analysis from standardized investigative transesophageal echocardiographic examinations performed after induction of anesthesia. MEASUREMENTS AND MAIN RESULTS: The authors compared the ability of intraoperative global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) strain to predict adverse postoperative outcomes, including prolonged hospitalization and the need for pharmacologic hemodynamic support after cardiac surgery. The association of GLS, GCS, and GRS with prolonged hospitalization (>7 days) and the need for pharmacologic hemodynamic support, with epinephrine or norepinephrine after cardiopulmonary bypass, were assessed using separate multivariable logistic regression models with adjustment for multiple comparisons. Of 100 patients, 86 had acceptable measurements for GLS analysis, 73 for GCS, and 72 for GRS. Worse GLS was associated with prolonged hospitalization [odds ratio [OR] (98.3% confidence interval [CI]) of 1.21 (1.01-1.46) per-unit worsening in strain (p = 0.01, significance criterion <0.0167)] and the need for inotropic support with epinephrine [OR (99.2% CI) of 1.81 (1.10-2.97) per-unit worsening in strain (p = 0.002, significance criterion <0.0083)], but not norepinephrine. GCS and GRS were not associated with adverse outcomes. CONCLUSION: GLS, but not GCS or GRS, predicts prolonged hospitalization and the requirement for inotropic support with epinephrine after AVR.

Intraoperative assessment of mitral valve repair: Validation of the saline test with nonresectional repair techniques.

BACKGROUND AND AIM: Intraoperative assessment of the repaired mitral valve (MV) by saline testing is a standard maneuver in MV repair. Despite a growing interest in application of nonresectional techniques, the utility of the saline test following repair with neochordae has not been systematically assessed. We sought to determine the accuracy of the saline test following MV repair using nonresectional techniques. MATERIALS AND METHODS: We included 25 adult patients undergoing MV repair for degenerative valve disease between November 2018 and February 2019. The surgical repair was performed using nonresectional techniques with neochordae either through a sternotomy or a robotic approach. RESULTS: Twenty-five patients underwent successful MV repair, all with excellent echocardiographic results. In four patients (16%), the saline test suggested discrete areas of leaflet malcoaptation and leakage, leading to additional repair maneuvers. In 16 patients (64%), the final saline test demonstrated excellent coaptation with little or no leak. In nine patients (36%), the final saline test was inconclusive (ventricle could not be filled) or poor (diffuse leak). Post-repair intraoperative echocardiography demonstrated no or trivial mitral regurgitation in all patients, and no patient required a second pump run. CONCLUSION: After repair with neochordae, a satisfactory saline test indicates a good repair and discrete leaks on the saline test suggest the need for further surgical maneuvers. If the surgeon has employed standard repair techniques using neochordae but the saline test is inconclusive or poor, additional repair maneuvers are generally unnecessary, as intraoperative echocardiography will usually demonstrate a good repair.

Value of perioperative inhaled epoprostenol with low tidal volume ventilation for complex endocarditis surgery.

BACKGROUND AND AIM: To compare outcomes of patients treated with inhaled epoprostenol and low tidal volume ventilation during cardiopulmonary bypass with those who did not receive this medication in the operating room at all, and those who received it as a rescue therapy at the end of the case. METHODS: Retrospective chart review between 2014 and 2017, follow-up included the entire hospital stay. RESULTS: Seventy-one patients were included, and mean age was 54 years. 78.9% of the patients were male. Procedures included 96% (n = 68) aortic valve replacement, 28% (n = 20) reconstruction of the intravalvular fibrosa, and 13% (n = 9) repair of an endocarditis-related intracardiac fistula. Patients who received epoprostenol (iEpo) (treatment and rescue groups), when compared with the control group had more intra-aortic balloon pump placement (23% vs 2.5%, P = .018), open chest after surgery (32% vs 7.5%, P = .012), and duration of mechanical ventilation (8.3 ± 2.7 vs. 2.4 ± 0.4 days, P = 0.01). There was no significant difference between the two groups in terms of extracorporeal circulatory support (6.5% vs 2.5%, P = .577) and hospital death (13% vs 10%, P = .72). In a subanalysis, hospital death and duration of mechanical ventilation were higher in the recue group when compared with the treatment group (P = .004 and .056, respectively). CONCLUSIONS: Prophylactic application of iEpo with low tidal volume ventilation for an anticipated complex endocarditis operation may contribute to favorable outcome when compared with postoperative epoprostenol rescue.

Surgical ablation of atrial fibrillation during mitral-valve surgery.

BACKGROUND: Among patients undergoing mitral-valve surgery, 30 to 50% present with atrial fibrillation, which is associated with reduced survival and increased risk of stroke. Surgical ablation of atrial fibrillation has been widely adopted, but evidence regarding its safety and effectiveness is limited. METHODS: We randomly assigned 260 patients with persistent or long-standing persistent atrial fibrillation who required mitral-valve surgery to undergo either surgical ablation (ablation group) or no ablation (control group) during the mitral-valve operation. Patients in the ablation group underwent further randomization to pulmonary-vein isolation or a biatrial maze procedure. All patients underwent closure of the left atrial appendage. The primary end point was freedom from atrial fibrillation at both 6 months and 12 months (as assessed by means of 3-day Holter monitoring). RESULTS: More patients in the ablation group than in the control group were free from atrial fibrillation at both 6 and 12 months (63.2% vs. 29.4%, P<0.001). There was no significant difference in the rate of freedom from atrial fibrillation between patients who underwent pulmonary-vein isolation and those who underwent the biatrial maze procedure (61.0% and 66.0%, respectively; P=0.60). One-year mortality was 6.8% in the ablation group and 8.7% in the control group (hazard ratio with ablation, 0.76; 95% confidence interval, 0.32 to 1.84; P=0.55). Ablation was associated with more implantations of a permanent pacemaker than was no ablation (21.5 vs. 8.1 per 100 patient-years, P=0.01). There were no significant between-group differences in major cardiac or cerebrovascular adverse events, overall serious adverse events, or hospital readmissions. CONCLUSIONS: The addition of atrial fibrillation ablation to mitral-valve surgery significantly increased the rate of freedom from atrial fibrillation at 1 year among patients with persistent or long-standing persistent atrial fibrillation, but the risk of implantation of a permanent pacemaker was also increased. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00903370.).

Cardiovascular Outcomes Assessment of the MitraClip in Patients with Heart Failure and Secondary Mitral Regurgitation: Design and rationale of the COAPT trial.

BACKGROUND: Patients with heart failure (HF) and symptomatic secondary mitral regurgitation (SMR) have a poor prognosis, with morbidity and mortality directly correlated with MR severity. Correction of isolated SMR with surgery is not well established in this population, and medical management remains the preferred approach in most patients. The Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation (COAPT) trial was designed to determine whether transcatheter mitral valve (MV) repair with the MitraClip device is safe and effective in patients with symptomatic HF and clinically significant SMR. STUDY DESIGN: The COAPT trial is a prospective, randomized, parallel-controlled, open-label multicenter study of the MitraClip device for the treatment of moderate-to-severe (3+) or severe (4+) SMR (as verified by an independent echocardiographic core laboratory) in patients with New York Heart Association class II-IVa HF despite treatment with maximally tolerated guideline-directed medical therapy (GDMT) who have been determined by the site's local heart team as not appropriate for MV surgery. A total of 614 eligible subjects were randomized in a 1:1 ratio to MV repair with the MitraClip plus GDMT versus GDMT alone. The primary effectiveness end point is recurrent HF hospitalizations through 24 months, analyzed when the last subject completes 12-month follow-up, powered to demonstrate superiority of MitraClip therapy. The primary safety end point is a composite of device-related complications at 12 months compared to a performance goal. Follow-up is ongoing, and the principal results are expected in late 2018. CONCLUSIONS: HF patients with clinically significant SMR who continue to be symptomatic despite optimal GDMT have limited treatment options and a poor prognosis. The randomized COAPT trial was designed to determine the safety and effectiveness of transcatheter MV repair with the MitraClip in symptomatic HF patients with moderate-to-severe or severe SMR.

Hyperinsulinemic Normoglycemia during Cardiac Surgery Reduces a Composite of 30-day Mortality and Serious In-hospital Complications: A Randomized Clinical Trial.

BACKGROUND: Hyperinsulinemic normoglycemia augments myocardial glucose uptake and utilization. We tested the hypothesis that hyperinsulinemic normoglycemia reduces 30-day mortality and morbidity after cardiac surgery. METHODS: This dual-center, parallel-group, superiority trial randomized cardiac surgical patients between August 2007 and March 2015 at the Cleveland Clinic, Cleveland, Ohio, and Royal Victoria Hospital, Montreal, Canada, to intraoperative glycemic management with (1) hyperinsulinemic normoglycemia, a fixed high-dose insulin and concomitant variable glucose infusion titrated to glucose concentrations of 80 to 110 mg · dl; or (2) standard glycemic management, low-dose insulin infusion targeting glucose greater than 150 mg · dl. The primary outcome was a composite of 30-day mortality, mechanical circulatory support, infection, renal or neurologic morbidity. Interim analyses were planned at each 12.5% enrollment of a maximum 2,790 patients. RESULTS: At the third interim analysis (n = 1,439; hyperinsulinemic normoglycemia, 709, standard glycemic management, 730; 52% of planned maximum), the efficacy boundary was crossed and study stopped per protocol. Time-weighted average glucose concentration (means ± SDs) with hyperinsulinemic normoglycemia was 108 ± 20 versus 150 ± 33 mg · dl with standard glycemic management, P < 0.001. At least one component of the composite outcome occurred in 49 (6.9%) patients receiving hyperinsulinemic normoglycemia versus 82 (11.2%) receiving standard glucose management (P < efficacy boundary 0.0085); estimated relative risk (95% interim-adjusted CI) 0.62 (0.39 to 0.97), P = 0.0043. There was a treatment-by-site interaction (P = 0.063); relative risk for the composite outcome was 0.49 (0.26 to 0.91, P = 0.0007, n = 921) at Royal Victoria Hospital, but 0.96 (0.41 to 2.24, P = 0.89, n = 518) at the Cleveland Clinic. Severe hypoglycemia (less than 40 mg · dl) occurred in 6 (0.9%) patients. CONCLUSIONS: Intraoperative hyperinsulinemic normoglycemia reduced mortality and morbidity after cardiac surgery. Providing exogenous glucose while targeting normoglycemia may be preferable to simply normalizing glucose concentrations.

Patients at High Risk for Obstructive Sleep Apnea Are at Increased Risk for Atrial Fibrillation After Cardiac Surgery: A Cohort Analysis.

BACKGROUND: Patients with obstructive sleep apnea (OSA) experience intermittent hypoxia, hypercarbia, and sympathetic activation during sleep, which increases risk for paroxysmal atrial fibrillation and other cardiac arrhythmias. Whether patients with OSA experience increased episodes of atrial fibrillation after cardiac surgery is unclear. We examined whether patients at increased risk for OSA, assessed by the STOP-BANG (snoring, tired during the day, observed stop breathing during sleep, high blood pressure, body mass index more than 35 kg/m, age more than 50 years, neck circumference more than 40 cm, and male gender) questionnaire, had a higher incidence of new-onset postoperative atrial fibrillation after cardiac surgery. Because both postoperative atrial fibrillation and OSA increase resource utilization, we secondarily examined whether patients at increased OSA risk had longer duration of postoperative mechanical ventilation and intensive care unit (ICU) length of stay. METHODS: With institutional review board approval, this retrospective observational study evaluated adult patients who underwent elective cardiac surgery requiring cardiopulmonary bypass between 2014 and 2015 with preoperative assessment of OSA risk using the STOP-BANG questionnaire. Patients with a history of atrial fibrillation were excluded. The association between the STOP-BANG score and postoperative atrial fibrillation was examined using a multivariable logistic regression model. Secondarily, we estimated the association between the STOP-BANG score and duration of initial intubation using multivariable linear regression and ICU length of stay using Cox proportional hazards regression. We also descriptively summarized the percentage of patients requiring tracheal reintubation for mechanical ventilation. RESULTS: Of 4228 cardiac surgery patients, 1593 met inclusion and exclusion criteria. An increased STOP-BANG score was associated with higher odds of postoperative atrial fibrillation (odds ratio [95% confidence interval {CI}], 1.16 [1.09-1.23] per-point increase in the STOP-BANG score; P < .001). The STOP-BANG score was not associated with ICU length of stay (estimated hazard ratio [97.5% CI], 0.99 [0.96-1.03] per-point increase in the STOP-BANG score; P = .99) or duration of initial intubation (ratio of geometric means [97.5% CI], 1.01 [1.00-1.04]; P = .03; significance criterion [Bonferroni correction] < 0.025). One percent of patients required reintubation. DISCUSSION: Increasing risk for OSA, assessed by STOP-BANG, was associated with higher odds of postoperative atrial fibrillation, but not prolonged duration of mechanical ventilation or ICU length of stay.

Reduced Left Ventricular Global Longitudinal Strain Predicts Prolonged Hospitalization: A Cohort Analysis of Patients Having Aortic Valve Replacement Surgery.

BACKGROUND: Left ventricular ejection fraction (LVEF) is often preserved in patients with aortic stenosis and thus cannot distinguish between normal myocardial contractile function and subclinical dysfunction. Global longitudinal strain and strain rate (SR), which measure myocardial deformation, are robust indicators of myocardial function and can detect subtle myocardial dysfunction that is not apparent with conventional echocardiographic measures. Strain and SR may better predict postoperative outcomes than LVEF. The primary aim of our investigation was to assess the association between global longitudinal strain and serious postoperative outcomes in patients with aortic stenosis having aortic valve replacement. Secondarily, we also assessed the associations between global longitudinal SR and LVEF and the outcomes. METHODS: In this post hoc analysis of data from a randomized clinical trial (NCT01187329), we examined the association between measures of myocardial function and the following outcomes: (1) need for postoperative inotropic/vasopressor support; (2) prolonged hospitalization (>7 days); and (3) postoperative atrial fibrillation. Standardized transesophageal echocardiographic examinations were performed after anesthetic induction. Myocardial deformation was measured using speckle-tracking echocardiography. Multivariable logistic regression was used to assess associations between measures of myocardial function and outcomes, adjusted for potential confounding factors. The predictive ability of global longitudinal strain, SR, and LVEF was assessed as area under receiver operating characteristics curves (AUCs). RESULTS: Of 100 patients enrolled in the clinical trial, 86 patients with aortic stenosis had acceptable images for global longitudinal strain analysis. Primarily, worse intraoperative global longitudinal strain was associated with prolonged hospitalization (odds ratio [98.3% confidence interval], 1.22 [1.01-1.47] per 1% decrease [absolute value] in strain; P = .012), but not with other outcomes. Secondarily, worse global longitudinal SR was associated with prolonged hospitalization (odds ratio [99.7% confidence interval], 1.68 [1.01-2.79] per 0.1 second(-1) decrease [absolute value] in SR; P = .003), but not other outcomes. LVEF was not associated with any outcomes. Global longitudinal SR was the best predictor for prolonged hospitalization (AUC, 0.72), followed by global longitudinal strain (AUC, 0.67) and LVEF (AUC, 0.62). CONCLUSIONS: Global longitudinal strain and SR are useful predictors of prolonged hospitalization in patients with aortic stenosis having an aortic valve replacement.