Barry A. Boilson

Readmissions after implantation of axial flow left ventricular assist device.

OBJECTIVES The purpose of this study was to determine the occurrence and causes of readmissions after implantation of axial flow left ventricular assist device (LVAD). BACKGROUND Based on the REMATCH (Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure) study experience, readmissions after LVAD implantation are thought to be frequent. METHODS We retrospectively analyzed admissions to our facility in a cohort of 115 patients implanted between January 2008 and July 2011 with the HeartMate II axial flow LVAD, of whom 42 were bridged to transplant. To account for repeated events, Andersen-Gill models were used to determine possible predictors. RESULTS The patients were followed for 1.4 ± 0.9 years. There were 224 readmissions in 83 patients. The overall readmission rate was 1.64 ± 1.97 per patient-year of follow-up. The readmission rate for the first 6 months was 2.0 ± 2.3 and decreased to 1.2 ± 2.1 during subsequent follow-up. Leading causes were bleeding (66 readmissions in 34 patients), mostly gastrointestinal bleed (51 in 27 patients), cardiac (51 in 36 patients, most for HF or arrhythmia), infections (32 in 25 patients) of which 6 were pump related, and thrombosis (20 in 15 patients) including 13 readmissions due to hemolysis. Preoperative variables associated with (fewer) readmissions in a multivariate model include residence within our hospital-extended referral zone of Minnesota and the neighboring states (hazard ratio: 0.66; 95% confidence interval: 0.48 to 0.91; p = 0.011), hemoglobin (hazard ratio: 0.91, 95% confidence interval: 0.84 to 0.99; p = 0.027) and N-terminal pro-B-type natriuretic peptide (hazard ratio: 0.98; 95% confidence interval: 0.96 to 1.0 per 1,000-unit increase, p = 0.022). C-statistic for the model: 0.63. CONCLUSIONS Readmission rates after axial flow LVAD implantation decrease during the first 6 months and then stabilize. The leading causes are bleeding, cardiac (heart failure and arrhythmia), infections, and thrombosis.

Palliative Medicine Consultation for Preparedness Planning in Patients Receiving Left Ventricular Assist Devices as Destination Therapy

OBJECTIVE To assess the benefit of proactive palliative medicine consultation for delineation of goals of care and quality-of-life preferences before implantation of left ventricular assist devices as destination therapy (DT). PATIENTS AND METHODS We retrospectively reviewed the cases of patients who received DT between January 15, 2009, and January 1, 2010. RESULTS Of 19 patients identified, 13 (68%) received proactive palliative medicine consultation. Median time of palliative medicine consultation was 1 day before DT implantation (range, 5 days before to 16 days after). Thirteen patients (68%) completed advance directives. The DT implantation team and families reported that preimplantation discussions and goals of care planning made postoperative care more clear and that adverse events were handled more effectively. Currently, palliative medicine involvement in patients receiving DT is viewed as routine by cardiac care specialists. CONCLUSION Proactive palliative medicine consultation for patients being considered for or being treated with DT improves advance care planning and thus contributes to better overall care of these patients. Our experience highlights focused advance care planning, thorough exploration of goals of care, and expert symptom management and end-of-life care when appropriate.

Changes in renal function after implantation of continuous-flow left ventricular assist devices.

OBJECTIVES The aim of this study was to determine renal outcomes after left ventricular assist device (LVAD) implantation. BACKGROUND Renal dysfunction before LVAD placement is frequent, and it is unclear whether it is due to primary renal disease or to poor perfusion. METHODS A retrospective single-center analysis was conducted in 83 consecutive patients implanted with HeartMate II continuous-flow LVADs (Thoratec Corp., Pleasanton, California). Calculated glomerular filtration rate (GFR) was assessed on admission and 1, 3, and 6 months after implantation. To define predictors for improvement in GFR, clinical variables were examined in patients with decreased renal function (GFR <60 ml/min/1.73 m(2)) before LVAD, surviving and dialysis-free at 1 month (n = 44). RESULTS GFR significantly increased from admission (53.2 ± 21.4 ml/min/1.73 m(2)) to 1 month after LVAD implantation (87.4 ± 27.9 ml/min/1.73 m(2)) (p < 0.0001). Subsequently, at 3 and 6 months, GFR remained significantly (p < 0.0001) above pre-LVAD values. Of the 51 patients with GFRs <60 ml/min/1.73 m(2) before LVAD surviving at 1 month, 34 (67%) improved to GFRs >60 ml/min/1.73 m(2). Univariate pre-operative predictors for improvement in renal function at 1 month included younger age (p = 0.049), GFR improvement with optimal medical therapy (p < 0.001), intra-aortic balloon pump use (p = 0.004), kidney length above 10 cm (p = 0.023), no treatment with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (p = 0.029), higher bilirubin (p = 0.002), higher Lietz-Miller score (p = 0.019), and atrial fibrillation (p = 0.007). Multivariate analysis indicated pre-operative improved GFR (slope = 0.5 U per unit improved; 95% confidence interval: 0.2 to 0.8; p = 0.003), atrial fibrillation (slope = 27; 95% confidence interval: 8 to 46; p = 0.006), and intra-aortic balloon pump use (slope = 14; 95% confidence interval: 2 to 26; p = 0.02) as independent predictors. CONCLUSIONS In most patients with end-stage heart failure considered for LVAD implantation, renal dysfunction is reversible and likely related to poor renal perfusion.

Bilateral Internal Thoracic Artery Harvest and Deep Sternal Wound Infection in Diabetic Patients

BACKGROUND Coronary artery bypass graft surgery is superior to percutaneous intervention in diabetic patients with multivessel disease. The use of bilateral internal thoracic arteries (BITA) may provide better long-term graft patency, but the risk of postoperative deep sternal wound infection has limited its use in diabetic patients. However, studies have reported conflicting results, and require systematic evaluation. METHODS MEDLINE, EMBASE, World of Science, and the Cochrane library were searched for randomized controlled trials and observational studies comparing the incidence of deep sternal wound infection in diabetic patients undergoing either left internal thoracic artery (LITA) or BITA harvest. We used random effect models to compare risk ratios within groups. RESULTS One randomized controlled trial and 10 observational studies (126,235 diabetic patients: 122,465 LITA, 3,770 BITA) met inclusion criteria. Deep sternal wound infection occurred in 3.1% and 1.6% for the BITA and LITA cohorts, respectively. The risk ratio for deep sternal wound infection development was 1.71 (1.37 to 2.14) for BITA compared with LITA. Patients who underwent skeletonized BITA harvest had a similar risk of deep sternal wound infection compared with LITA (0.9 [0.42 to 2.09]), although pedicled harvest demonstrated increased risk (1.77 [1.4 to 2.23]). Early mortality was comparable in the LITA cohort (2.5%) and the BITA cohort (2.3%; p = 0.8). CONCLUSIONS The risk of deep sternal wound infection can be minimized in diabetic patients undergoing coronary artery bypass graft surgery by performing ITA harvested in a skeletonized manner with meticulous attention to preserving sternal blood flow. Pedicled harvest is to be discouraged when utilizing both ITA owing to a significant increase in the risk of postoperative deep sternal wound infection.

Sirolimus as Primary Immunosuppression Attenuates Allograft Vasculopathy With Improved Late Survival and Decreased Cardiac Events After Cardiac Transplantation

Background— We retrospectively analyzed the potential of sirolimus as a primary immunosuppressant in the long-term attenuation of cardiac allograft vasculopathy progression and the effects on cardiac-related morbidity and mortality. Methods and Results— Forty-five cardiac transplant recipients were converted to sirolimus 1.2 years (0.2, 4.0) after transplantation with complete calcineurin inhibitor withdrawal. Fifty-eight control subjects 2.0 years (0.2, 6.5 years) from transplantation were maintained on calcineurin inhibitors. Age, sex, ejection fraction, and time from transplantation to baseline intravascular ultrasound study were not different (P>0.2 for all) between the groups; neither were secondary immunosuppressants and use of steroids. Three-dimensional intravascular ultrasound studies were performed at baseline and 3.1 years (1.3, 4.6 years) later. Plaque index progression (plaque volume/vessel volume) was attenuated in the sirolimus group (0.7±10.5% versus 9.3±10.8%; P=0.0003) owing to reduced plaque volume in patients converted to sirolimus early (<2 years) after transplantation (P=0.05) and improved positive vascular remodeling (P=0.01) in patients analyzed late (>2 years) after transplantation. Outcome analysis in 160 consecutive patients maintained on 1 therapy was performed regardless of performance of intravascular ultrasound examinations. Five-year survival was improved with sirolimus (97.4±1.8% versus 81.8±4.9%; P=0.006), as was freedom from cardiac-related events (93.6±3.2% versus 76.9±5.5%; P=0.002). Conclusions— Substituting calcineurin inhibitor with sirolimus as primary immunosuppressant attenuates long-term cardiac allograft vasculopathy progression and may improve long-term allograft survival owing to favorable coronary remodeling. Because of the lack of randomization and retrospective nature of our analysis, the differences in outcome should be interpreted cautiously, and prospective clinical trials are required.

Dual anti-platelet therapy after coronary artery bypass grafting: Is there any benefit? A systematic review and meta-analysis

Anti‐platelet therapy is an important component of medical therapy post coronary artery bypass grafting (CABG). While aspirin administration is a Class I indication after CABG, the benefit of concomitant clopidogrel is a controversial issue.

Echocardiographic Variables After Left Ventricular Assist Device Implantation Associated With Adverse Outcome

Background— Operative mortality after left ventricular assist device (LVAD) implantation is heavily influenced by patient selection and the technical difficulty of surgery. However, how we treat our patients and LVAD setting may affect the patient outcome beyond this period. We postulated that the presence of echocardiographic variables 1 month after surgery suggesting appropriate degree of LV unloading and an adequate forward flow would be important in determining clinical outcomes after the initial successful LVAD implantation. Methods and Results— We retrospectively analyzed various variables in echocardiographic examinations performed 30 days after LVAD implant in 76 consecutive patients receiving continuous flow device for their association with a compound end point (90-day mortality, readmission for heart failure, or New York Heart Association class III or higher at the end of the 90-day period). The echocardiographic associations examined included estimated LVAD flow, with and without native LV contribution, interventricular septal position, the status of aortic valve opening, an estimated left atrial pressure (ELAP), the mitral flow E-wave deceleration time, and the ratio of deceleration time to E-wave velocity (mitral deceleration index [MDI]). Four patients died during the 30- to 90-day period, 6 patients were readmitted for heart failure, and 25 patients were considered to have New York Heart Association class III or higher at the end of the 90-day period. Variables associated with adverse outcome included increased ELAP (odds ratio, 1.30 [1.16–1.48]; P<0.0001), MDI <2 ms/[cm/s] (odds ratio, 4.4 implantation [1.22–18]; P=0.02) and decreased tricuspid lateral annulus velocity (odds ratio, 0.70 implantation [0.48–0.95]; P=0.02). A leftward deviation of interventricular septum was associated with a worse outcome (odds ratio, 3.03 implantation [1.21–13.3]; P=0.01). Conclusions— Mortality and heart failure after LVAD surgery appear to be predominantly determined by echocardiographic evidence of inefficient unloading of the left ventricle and persistence of right ventricular dysfunction. Increased estimated LA pressure and short MDI are associated with worse mid term outcome. Leftward deviation of the septum is associated with worse outcome as well.Background —Operative mortality following LVAD implantation is heavily influenced by patient selection and the technical difficulty of surgery. However, how we manage our patients and LVAD setting may affect the patient outcome beyond this period. We postulated that the presence of echocardiographic variables one month after surgery suggesting appropriate degree of LV unloading and an adequate forward flow would be important in determining clinical outcomes following the initial successful LVAD implantation. Methods and Results —We retrospectively analyzed various variables in echocardiographic examinations performed 30 days after LVAD implant in 76 consecutive patients receiving continuous flow device (Heart Mate II) for their association with a compound endpoint (90 day mortality, re-admission for heart failure, or NYHA≥III at the end of the 90 day period). The echocardiographic associations examined included estimated LVAD flow, with and without native LV contribution, inter-ventricular septal position, the status of aortic valve opening, an estimated left atrial pressure (ELAP), the mitral flow E wave deceleration time and the ratio of deceleration time to E wave velocity (mitral deceleration index [MDI]). Four patients died during the 30-90 day period, six patients were re-admitted for heart failure, and 25 patients were considered to have NYHA≥III at the end of the 90 day period. Variables associated with adverse outcome included increased ELAP (Odds Ratio (OR) 1.30(1.16-1.48); p<0.0001), MDI<2 ms/ [cm/s] (OR 4.4(1.22-18); P=0.02) and decreased tricuspid lateral annulus velocity (OR 0.70(0.48-0.95); P=0.02). A leftward deviation of inter-ventricular septum was associated with a worse outcome (OR 3.03(1.21-13.3); P=0.01). Conclusions —Mortality and heart failure after LVAD surgery seem to be predominantly determined by echocardiographic evidence of inefficient unloading of left ventricle and persistence of RV dysfunction. Increased estimated LA pressure and short MDI are associated with worse mid term outcome. Leftward deviation of the septum is associated with worse outcome as well.

Echocardiographic predictors of adverse outcomes after continuous left ventricular assist device implantation.

OBJECTIVES The purpose of the study was to identify echocardiographic predictors of adverse outcome in patients implanted with continuous-flow left ventricular assist devices (LVAD). BACKGROUND Continuous flow LVAD have become part of the standard of care for the treatment of advanced heart failure. However, knowledge of echocardiographic predictors of outcome after LVAD are lacking. METHODS Overall, 83 patients received continuous-flow LVAD (HeartMate II, Thoratec Corporation, Pleasanton, California) from February 2007 to June 2010. The LVAD database, containing various echocardiographic parameters, was examined to analyze their influence on in-hospital mortality, a compound cardiac event (in-hospital mortality or acute right ventricular [RV] dysfunction), and long-term mortality. RESULTS Eight patients died before discharge (operative mortality 9.6%), and another 15 patients were considered to have acute RV dysfunction immediately after surgery. Patients with relatively small left ventricular end-diastolic diameters (<63 mm) had significantly higher risk for in-hospital mortality (odds ratio [OR]: 0.9; 95% confidence interval [CI]: 0.83 to 0.99; p = 0.04) or occurrence of the compound cardiac event (OR: 0.89; 95% CI: 0.84 to 0.95; p < 0.001). The most significant predictor of outcome was the decreased timing interval between the onset and the cessation of tricuspid regurgitation flow corrected for heart rate (TRDc), a surrogate for early systolic equalization of RV and right atrial pressure. Short TRDc predicted in-hospital mortality (OR: 0.85; 95% CI: 0.74 to 0.97; p = 0.01) and the compound cardiac event (OR: 0.83; 95% CI: 0.74 to 0.91; p < 0.0001). Multivariate analysis based on a logistic regression model demonstrated that the accuracy of predicting the 30-day compound adverse outcome was improved with the addition of echocardiographic variables when added to the commonly used hemodynamic or clinical scores. TRDc predicted long-term survival, with adjusted risk ratios of 0.89 for death from any cause (95% CI: 0.83 to 0.96; p = 0.003) and 0.88 for cardiac-related death (95% CI: 0.77 to 0.98; p = 0.03). CONCLUSIONS The presence of either a relatively small left ventricle (<63 mm) or early systolic equalization of RV and right atrial pressure (short TRDc) demonstrated by echocardiography is associated with increased 30-day morbidity and mortality. Prediction of early adverse outcomes by echocardiographic parameters is additive to laboratory or hemodynamic variables.

Echocardiographic Variables Post LVAD Associated with Adverse Outcome

Background— Operative mortality after left ventricular assist device (LVAD) implantation is heavily influenced by patient selection and the technical difficulty of surgery. However, how we treat our patients and LVAD setting may affect the patient outcome beyond this period. We postulated that the presence of echocardiographic variables 1 month after surgery suggesting appropriate degree of LV unloading and an adequate forward flow would be important in determining clinical outcomes after the initial successful LVAD implantation. Methods and Results— We retrospectively analyzed various variables in echocardiographic examinations performed 30 days after LVAD implant in 76 consecutive patients receiving continuous flow device for their association with a compound end point (90-day mortality, readmission for heart failure, or New York Heart Association class III or higher at the end of the 90-day period). The echocardiographic associations examined included estimated LVAD flow, with and without native LV contribution, interventricular septal position, the status of aortic valve opening, an estimated left atrial pressure (ELAP), the mitral flow E-wave deceleration time, and the ratio of deceleration time to E-wave velocity (mitral deceleration index [MDI]). Four patients died during the 30- to 90-day period, 6 patients were readmitted for heart failure, and 25 patients were considered to have New York Heart Association class III or higher at the end of the 90-day period. Variables associated with adverse outcome included increased ELAP (odds ratio, 1.30 [1.16–1.48]; P<0.0001), MDI <2 ms/[cm/s] (odds ratio, 4.4 implantation [1.22–18]; P=0.02) and decreased tricuspid lateral annulus velocity (odds ratio, 0.70 implantation [0.48–0.95]; P=0.02). A leftward deviation of interventricular septum was associated with a worse outcome (odds ratio, 3.03 implantation [1.21–13.3]; P=0.01). Conclusions— Mortality and heart failure after LVAD surgery appear to be predominantly determined by echocardiographic evidence of inefficient unloading of the left ventricle and persistence of right ventricular dysfunction. Increased estimated LA pressure and short MDI are associated with worse mid term outcome. Leftward deviation of the septum is associated with worse outcome as well.Background —Operative mortality following LVAD implantation is heavily influenced by patient selection and the technical difficulty of surgery. However, how we manage our patients and LVAD setting may affect the patient outcome beyond this period. We postulated that the presence of echocardiographic variables one month after surgery suggesting appropriate degree of LV unloading and an adequate forward flow would be important in determining clinical outcomes following the initial successful LVAD implantation. Methods and Results —We retrospectively analyzed various variables in echocardiographic examinations performed 30 days after LVAD implant in 76 consecutive patients receiving continuous flow device (Heart Mate II) for their association with a compound endpoint (90 day mortality, re-admission for heart failure, or NYHA≥III at the end of the 90 day period). The echocardiographic associations examined included estimated LVAD flow, with and without native LV contribution, inter-ventricular septal position, the status of aortic valve opening, an estimated left atrial pressure (ELAP), the mitral flow E wave deceleration time and the ratio of deceleration time to E wave velocity (mitral deceleration index [MDI]). Four patients died during the 30-90 day period, six patients were re-admitted for heart failure, and 25 patients were considered to have NYHA≥III at the end of the 90 day period. Variables associated with adverse outcome included increased ELAP (Odds Ratio (OR) 1.30(1.16-1.48); p<0.0001), MDI<2 ms/ [cm/s] (OR 4.4(1.22-18); P=0.02) and decreased tricuspid lateral annulus velocity (OR 0.70(0.48-0.95); P=0.02). A leftward deviation of inter-ventricular septum was associated with a worse outcome (OR 3.03(1.21-13.3); P=0.01). Conclusions —Mortality and heart failure after LVAD surgery seem to be predominantly determined by echocardiographic evidence of inefficient unloading of left ventricle and persistence of RV dysfunction. Increased estimated LA pressure and short MDI are associated with worse mid term outcome. Leftward deviation of the septum is associated with worse outcome as well.

Circulating CD34+ Cell Subsets in Patients with Coronary Endothelial Dysfunction

Background Endothelial dysfunction is an early manifestation of atherosclerotic disease. Circulating cells that express CD34, including endothelial and hematopoietic progenitor cells, might play a part in the development and progression of atherosclerosis. The aim of this study was to evaluate the association between coronary endothelial dysfunction and concentrations of circulating CD34+ cell subsets.Methods Intracoronary acetylcholine challenge was used to test for coronary endothelial dysfunction in 57 consecutive patients scheduled to undergo diagnostic coronary angiography and with no signs of substantial obstructive lesions. Mononuclear cells were extracted from whole blood samples taken from all patients, analyzed by flow cytometry for CD14, CD34, CD133, CD45, and vascular endothelial growth factor receptor 2 (VEGFR2), and cultured for functional analysis.Results Compared with patients with normal coronary endothelial function, in those with coronary endothelial dysfunction, the number of circulating CD34+/CD45dim/VEGFR2− cells, CD34+/CD45dim/CD133+/VEGFR2− cells and colony-forming units were reduced. Concentrations of CD34+/CD45−/VEGFR2+ cells did not differ between groups.Conclusions Regulation of CD34+ cell subsets seems to differ between patients with coronary endothelial dysfunction and those with normal coronary endothelial function. Changes in specific circulating progenitor cell subsets might, therefore, be an early manifestation of atherosclerosis.