Number and Type of Blood Products Are Negatively Associated With Outcomes After Cardiac Surgery.

BACKGROUND: The association between blood transfusion and adverse outcome is documented in cardiac surgery. However, the incremental significance of each unit transfused, whether red blood cell (RBC) or non-RBC, is uncertain. This study examined the relationship of patient outcomes with the type and number of blood product units transfused. METHODS: Statewide data from 24 082 adult cardiac surgery patients were included. The relationship with blood transfusion was assessed for morbidity and 30-day mortality using total number of RBC and non-RBC units transfused, specific type of non-RBC units, and different combinations of transfusion (only RBC, only non-RBC, RBC + non-RBC). Multivariable logistic regressions examined these associations. RESULTS: Median age was 66 years (30% female patients), and 51% of patients received a transfusion (31%-66% across hospitals). Risk-adjusted analyses found each blood product unit was associated with 9%, 7%, and 4% greater odds for 30-day mortality, major morbidity, and minor morbidity, respectively (all P < .001). Odds for 30-day mortality were 13% greater with each RBC unit (P < .001) and 6% greater for each non-RBC unit (P < .001). Each unit of fresh frozen plasma (P < .001) and platelets (P < .001) increased the odds for 30-day mortality, but no effect was found for cryoprecipitate (P = .725). Odds for 30-day mortality were lower for non-RBC-only (odds ratio, 0.52; P = .030) and greater for RBC + non-RBC (odds ratio, 2.98; P < .001) compared with RBC-only transfusion. CONCLUSIONS: Independent of center variability on transfusion methods, each additional unit transfused was associated with increased odds for complications, with RBC transfusion carrying greater risk compared with non-RBC. Comprehensive evidence-based clinical approaches and coordination are needed to guide each blood transfusion event after cardiac surgery.

The long-term safety and efficacy of concomitant Cox maze procedures for atrial fibrillation in patients without mitral valve disease.

OBJECTIVE: Newly published guidelines made the highest level recommendation for surgical treatment for atrial fibrillation. However, the number of patients without a mitral valve procedure with atrial fibrillation who are treated with concomitant surgical ablation is still low (15%-25%), because surgeons are reluctant to perform procedures in patients who would not otherwise require left atriotomy. The purpose of this study was to compare the outcomes of concomitant Cox maze with and without mitral valve procedures. METHODS: Patients who underwent concomitant Cox maze procedures were prospectively followed since September 2005. Of the 711 patients, 238 did not receive mitral valve surgery. Propensity score matching was conducted to balance preoperative characteristics between patients with and without mitral valve procedures (164/group after matching). RESULTS: Before matching, patients in the mitral valve group were younger (65 vs 67 years, P = .047) and had higher euroSCORE II (European System for Cardiac Operative Risk Evaluation; 3.2% vs 2.6%, P = .002), larger mean left atrial size (5.3 vs 4.8 cm, P < .001), and shorter median atrial fibrillation duration (19 vs 25 months, P = .064). Early outcomes were similar for the matched groups. Cumulative 5-year freedom from stroke did not differ between matched mitral valve and non-mitral valve groups (96.1% vs 96.6%, P = .667). At each time point, the proportion in sinus rhythm off antiarrhythmic medications was similar for the matched groups, including 5 years after surgery (68% vs 63%, P = .492). CONCLUSIONS: The Cox maze procedure is safe and effective with comparable outcomes when performed concomitant to mitral valve or non-mitral valve surgery. Surgeons should base the decision to perform surgical ablation procedures on atrial fibrillation pathophysiology and the benefit to patients, not on the type of concomitant procedure.

Long-term outcome following concomitant mitral valve surgery and Cox maze procedure for atrial fibrillation.

OBJECTIVE: Atrial fibrillation (AF) is associated with increased early and long-term morbidity/mortality following valve surgery. This study examined long-term influence of concomitant full Cox maze (CM) and mitral valve procedures on freedom from atrial arrhythmia and stroke. METHODS: This sample comprised patients who underwent CM with a mitral valve procedure (N = 473). Data on rhythm, medication status, and clinical events captured according to Heart Rhythm Society guidelines at 6, 9, 12, 18, and 24 months and yearly thereafter up to 7 years. RESULTS: Mean age was 65 years, mean left atrium size was 5.3 cm, and 15% had paroxysmal AF. Perioperative stroke occurred in 2 patients (0.4%) and operative mortality was 2.7% (n = 13). Return to sinus rhythm regardless of antiarrhythmic drugs at 1, 5, and 7 years was 90%, 80%, and 66%. Sinus rhythm off antiarrhythmic drugs at 1, 5, and 7 years was 83%, 69%, and 55%. Freedom from embolic stroke at 7 years was 96.6% (0.4 strokes per 100 patient-years) with a majority of patients off anticoagulation medication. Greater odds of atrial arrhythmia recurrence during 7 years was associated with longer AF duration (odds ratio [OR], 1.07; P = .001), whereas lower odds were associated with cryothermal energy only (OR, 0.64; P = .045) and greater surgeon experience (OR, 0.98; P = .025). CONCLUSIONS: This study suggests that the addition of CM to mitral valve procedures, even with a high degree of complexity, did not increase operative risk. In long-term follow-up, the CM procedure demonstrated acceptable rhythm success, reduced AF burden, and remarkably low stroke rate. Individual surgeon experience and training may notably influence long-term surgical ablation for AF success.

The use of del Nido cardioplegia in adult cardiac surgery: A prospective randomized trial.

OBJECTIVES: The del Nido cardioplegia solution has been used extensively in congenital heart surgery for more than 20 years and more recently for adults. This randomized controlled trial examined whether expanding this technique to adult cardiac surgery confers benefits in surgical workflow and clinical outcome compared with blood-based cardioplegia. METHODS: Adult first-time coronary artery bypass grafting (CABG), valve, or CABG/valve surgery patients requiring cardiopulmonary bypass (CPB) were randomized to del Nido cardioplegia (n = 48) or whole blood cardioplegia (n = 41). Primary outcomes assessed myocardial preservation. Troponin I was measured at baseline, 2 hours after CPB termination, 12 and 24 hours after cardiovascular intensive care unit admission. Alpha was set at P < .001. RESULTS: Preoperative characteristics were similar between groups, including age, Society of Thoracic Surgeons risk score, CABG, and valve procedures. There was no significant difference on CPB time (97 vs 103 minutes; P = .288) or crossclamp time (70 vs 83 minutes; P = .018). The del Nido group showed higher return to spontaneous rhythm (97.7% vs 81.6%; P = .023) and fewer patients required inotropic support (65.1% vs 84.2%; P = .050), but did not reach statistical significance. Incidence of Society of Thoracic Surgeons-defined morbidity was low, with no strokes, myocardial infarctions, renal failure, or operative deaths. For del Nido group patients, troponin levels did not increase as much as for control patients (P = .040), but statistical significance was not reached. CONCLUSIONS: Evidence from this study suggests del Nido cardioplegia use in routine adult cases may be safe, result in comparable clinical outcomes, and streamline surgical workflow. The trend for troponin should be investigated further because it may suggest superior myocardial protection with the del Nido solution.

Does Surgical Ablation Energy Source Affect Long-Term Success of the Concomitant Cox Maze Procedure?

BACKGROUND: The Cox maze (CM) procedure is routinely performed using surgical ablation technology. Reports are scarce on long-term outcomes of CM, especially for a large series of patients. This study examined the potential impact of surgical ablation energy source on safety and long-term efficacy of concomitant CM procedures. METHODS: The study sample consisted of 709 concomitant CM-treated patients operated on with cryothermal energy only (group 1; n = 386) or combination of cryothermal and bipolar radiofrequency (group 2; n = 323). Data were collected prospectively on perioperative outcomes, rhythm status, survival, and clinical events. Propensity score matching conducted by energy source resulted in 298 patients per group. RESULTS: Perioperative outcomes included stroke (n = 4), reoperation for bleeding (n = 23), renal failure requiring temporary dialysis (n = 18), readmissions before 30 days (n = 86), and operative death before 30 days (n = 16; ratio of observed to expected mortality [O/E ratio], 0.50). Independent predictors for 1-year and 5-year rhythm success were a shorter history of atrial fibrillation (1-year odds ratio [OR], 0.93, p = 0.001; 5-year OR, 0.93, p = 0.042) and cryothermia alone (1-year OR=1.77, p = 0.020; 5-year OR = 2.29, p = 0.009). After matching, group 1 had significantly higher sinus rhythm without antiarrhythmic drugs at 6 months (79% vs 70%; p = 0.016), 36 months (81% vs 69%; p = 0.010), and 60 months (75% vs 57%; p = 0.008). Stroke incidence was lower for group 1 (0.7% vs 3%; p = 0.033), with no difference in major bleeding (10% vs 11%; p = 0.597). Groups had similar survival rates (log rank, 0.6; p = 0.452). CONCLUSIONS: Concomitant CM procedures performed with cryothermal energy alone or combined with bipolar radiofrequency ablation are safe and exceedingly effective. The association of cryothermal energy alone with higher rates of sinus rhythm and stroke reduction should be investigated further.

Outcomes of Patients Receiving Temporary Circulatory Support Before Durable Ventricular Assist Device.

BACKGROUND: Temporary circulatory support (TCS) is used to stabilize patients in critical cardiogenic shock and bridge patients to a durable ventricular assist device (VAD). Whether TCS confers increased risk at the time of VAD implant is unknown. METHODS: Prospectively collected data from five institutions was retrospectively reviewed. All profile 1 through profile 3 patients implanted with a continuous-flow VAD (n = 804) were categorized into three groups: TCS (n = 68); non-TCS profile 1 (n = 70); and non-TCS profile 2-3 (n = 666). RESULTS: End-organ function and hemodynamics were worse before TCS than in non-TCS profile 1 patients: creatinine (1.7 ± 0.1 mg/dL versus 1.3 ± 0.06 mg/dL, p = 0.003); and right atrial pressure (16 ± 0.8 mm Hg versus 13 ± 1.1 mm Hg, p = 0.048). The TCS restored cardiac output before durable VAD (4.9 ± 0.2 L/min), and was comparable to profile 2-3 patients (4.3 ± 0.05 L/min) and better than profile 1 patients (4.0 ± 0.2 L/min, p = 0.002). Markers of hepatic function such as bilirubin were impaired before VAD in TCS and profile 1 patients (2.0 ± 0.2 mg/dL) compared with profile 2 and 3 patients (1.1 ± 0.03, p < 0.001). The incidence of postoperative right ventricular failure necessitating a right VAD was 21% for TCS patients and non-TCS profile 1 patients compared with 2% for profile 2-3 patients (p < 0.001). Profile 1 and TCS patients had similar 1-year survival (70% and 77%, p = 0.57), but inferior survival as compared with profile 2 and 3 patients (82%, p < 0.001). On multivariable analysis, TCS increased the hazard of death twofold. CONCLUSIONS: Temporary circulatory support restores hemodynamics and reverses end-organ dysfunction. Nevertheless, these patients have high residual risk with postoperative morbidity and mortality that parallels profile 1 patients without TCS. Caution is suggested in downgrading risk for TCS patients with improved hemodynamic stability.

The Effect of Initiation of a Transcatheter Aortic Valve Replacement Program in the Treatment of Severe Aortic Stenosis.

We assessed the effect of a transcatheter aortic valve replacement (TAVR) program and Heart Team concept on our approach to severe isolated symptomatic aortic stenosis (AS) with regard to surgical practice, patient selection, perioperative outcomes, 1-year survival, and AVR volume. TAVR program began in August 2011. Patients having isolated surgical AVR between January 2008 and August 2011, when the program began (n = 282, 42 months), were compared with those after the program began until February 2015 (n = 344, surgical AVR and n = 126, TAVR, 42 months). Isolated surgical AVR accounted for 21% of all valve procedures (isolated and concomitant) before and after the TAVR program. However, the volume of all isolated AVR (surgical and transcatheter) increased to 27% of all valve procedures (isolated and concomitant) after the TAVR program implementation. Mean Society Of Thoracic Surgeons (STS)-predicted mortality risk was similar among patients who had surgical AVR pre-TAVR and post-TAVR implementation (2.3% vs 2.1%, P = 0.227), but addition of patients who had TAVR (STS risk = 7.1%) increased STS-predicted risk for all isolated AVR (surgical and transcatheter) procedures (2.3% vs 3.4%, P < 0.001). A similar trend was found for age, including a slight decrease in octogenarians for surgical AVR post-TAVR (18% vs 13%, P = 0.084). Operative mortality for isolated surgical AVR was similar in pre-TAVR and post-TAVR (2.1% vs 1.8%, P = 0.798), as were observed/expected (O/E) ratios (0.91 vs 0.82). For all isolated AVR, O/E ratio was 0.91 pre-TAVR and 0.82 post-TAVR (n = 470), including O/E = 0.79 for patients who had TAVR. No changes were found in proportion of isolated surgical AVR cases or patient risk and outcomes after introduction of TAVR program and Heart Team. However, volume of patients with severe AS treated increased significantly post-TAVR. Our results reflect growing awareness of TAVR availability and accompanying increases in patients referred to our Heart Team for AS treatment.

Practice changes in blood glucose management following open heart surgery: from a prospective randomized study to everyday practice.

OBJECTIVES: Targeted blood glucose (BG) levels following cardiac surgery continues to be debated. According to the Society of Thoracic Surgeons (STS) guidelines, BG should be kept <180 mg/dl following cardiac surgery. However, our practice and others shifted to a stricter BG control (90-110 mg/dl) based on data suggesting an association with improved outcome. Recently, we conducted a randomized control study that demonstrated no added value to stricter control over liberal control (120-180 mg/dl). As a result, we shifted our management accordingly. The purpose of this study was to evaluate the impact that this change to a more liberal BG management (BGM) had on patient outcomes at our centre. METHODS: BGM was changed in June 2011 from strict (90-110 mg/dl) to liberal (120-180 mg/dl). Insulin drips, managed through a computerized algorithm, controlled BG for the first 72 h post surgery. Consecutive cardiac surgery patients operated on throughout 1 year prior to BGM change (n = 934) were propensity score matched to patients operated on throughout 1 year after the change (n = 927). RESULTS: After matching, there were 846 patient pairs. There was no difference between cohorts for length of stay and perioperative complications, and both cohorts achieved acceptable outcomes. Incidence of perioperative renal failure (P = 0.02) and renal failure requiring dialysis (P = 0.004) were better for the cohort with liberal BGM. One-year cumulative survival did not differ between cohorts (log-rank = 0.70, P = 0.40). CONCLUSIONS: Implementation of glycaemic control of 120-180 mg/dl into clinical practice was not associated with increased morbidity. The present results confirm our prior findings that a more liberal glycaemic control strategy to maintain BG is equal to a stricter target range. These findings are important for patient care and demonstrate the safety and efficacy of practice change for all patients following a successful randomized controlled trial.

Potential Impact of Modifiable Clinical Variables on Length of Stay After First-Time Cardiac Surgery.

BACKGROUND: Recent financial challenges highlight the importance of accurate prediction of length of hospital stay (LOS). We assessed reliability of The Society of Thoracic Surgeons (STS) risk prediction for extended and shorter LOS and examined whether modifiable clinical variables are associated with LOS in first-time cardiac surgery patients. METHODS: Isolated aortic valve, mitral valve, and coronary artery bypass graft surgery patients since 2008 were included (n = 3,472). Multivariate regression was used to evaluate nonmodifiable and potentially modifiable (preoperative hematocrit, hemoglobin A1c, body mass index, current smoker, major perioperative morbidity, and blood product transfusion) predictors of LOS in days. RESULTS: Mean age was 63.9 ± 11.2 years, 76% were males, and mean STS mortality risk was 1.9% ± 3.2%. Median (interquartile range) LOS was 4 (3 to 6) days. Predicted STS risk was 6.2% ± 7.1% for extended LOS (>14 days) and 48.3% ± 20.2% for short LOS (<6 days). Extended LOS was observed in 5.2% of patients (observed versus expected, 0.84; p = 0.019). Observed short LOS was better than predicted (67.8%; observed versus expected, 1.40; p < 0.001). Inclusion of modifiable variables in the LOS prediction model was significant (p < 0.001). Significant modifiable predictors were lower hematocrit, higher hemoglobin A1c, major morbidity, and transfusion. Longer predicted LOS from the model correlated with longer actual LOS (rs = 0.63; p < 0.001). Applying the prediction equation from the model to a hypothetical average patient, predicted LOS was 4.6 days. CONCLUSIONS: The STS risk model was reliably predictive of short and extended LOS but did not allow prediction of exact LOS in days. Accounting for potentially modifiable clinical variables, such as low hematocrit and blood transfusion, especially in elective patients, should lead to shorter LOS, higher satisfaction, and reduced financial burden.