Tadahisa Sugiura

Effect of obesity on outcomes in patients undergoing implantation of continuous-flow left ventricular assist devices

The purpose of this study was to analyze the effect of obesity on outcomes after continuous-flow left ventricular assist device (CF-LVAD) implantation. A single-center retrospective analysis was performed on 526 chronic heart failure patients who were implanted with the HeartMate II CF-LVAD (nu2009=u2009403) or HeartWare HVAD (nu2009=u2009123) between November 2003 and March 2016. Patients were stratified into 4 groups based on BMI: underweight (<u200918.5xa0kg/m2, nu2009=u200918, 3.4%), normal-weight (18.5–25xa0kg/m2, nu2009=u2009173, 32.9%), overweight (25–30xa0kg/m2, nu2009=u2009182, 30.2%), and obese (>u200930xa0kg/m2, nu2009=u2009153, 33.5%). The underweight group was excluded because of its small sample size. Records were reviewed to determine the incidence of postoperative complications and survival. Survival at 1, 6, 12, and 24 months were similar among normal-weight (91.3, 84.4, 76.3, and 67.6%), overweight (90.4, 80.8, 76.5, and 69.6%), and obese patients (90.7, 74.7, 65.3, and 61.3%, pu2009=u20090.24). Additionally, obesity was not a significant predictor of mortality in Cox proportional hazard models (hazard ratio 0.98, 95% confidence interval 0.766–1.277, pu2009=u20090.13). These findings suggest that appropriately selected obese patients receive similar survival benefit from CF-LVADs compared to non-obese patients, and obesity should not serve as a contraindication to CF-LVAD implantation.

Model of End-Stage Liver Disease-eXcluding International Normalized Ratio (MELD-XI) Scoring System to Predict Outcomes in Patients Who Undergo Left Ventricular Assist Device Implantation

BACKGROUNDnThe use of continuous-flow left ventricular assist devices (CF-LVADs) to treat advanced heart failure is increasing. Although risk scores, such as Model for End-Stage Liver Disease and the HeartMate II Risk Score, require the use of the international normalized ratio, many patients are on anticoagulation before CF-LVAD implantation. This study evaluated the ability of the Model of End-Stage Liver Disease-eXcluding International Normalized Ratio (MELD-XI) scoring system to predict clinical outcomes in patients with advanced heart failure who undergo CF-LVAD implantation.nnnMETHODSnA single-center retrospective review was performed of 524 patients who were implanted with the HeartMate II LVAD (Thoratec Corporation, Pleasanton, CA) or the HeartWare HVAD (HeartWare International Inc, Framingham, MA) between 2004 and 2016. Patients were stratified into two cohorts: those with a MELD-XI score of less than 14 (nxa0= 301) and 14 or higher (nxa0= 223).nnnRESULTSnPatients with the higher-risk MELD-XI score of 14 or higher demonstrated lower survival rates at 1, 3, 6, 12, and 24 months (p < 0.001 for all) and increased risk of early right heart failure and infections compared with patients with MELD-XI score of less than 14. MELD-XI was not significantly inferior at predicting 90-day mortality compared with the HeartMate II Risk Score (pxa0=xa00.92). Patients with elevated MELD-XI scores at follow-up demonstrated higher rates of mortality.nnnCONCLUSIONSnThese findings suggest that a MELD-XI score of 14 or higher was associated with a higher postoperative mortality rate than that seen in patients with a lower MELD-XI score. The MELD-XI scoring system can be used to predict outcomes in patients with advanced heart failure who undergo CF-LVAD implantation.

Left ventricular outflow tract closure during LVAD implantation: 2 cases of patients supported for over 6 years

We previously reported a series of 5 patients with advanced heart failure and aortic insufficiency (AI) who underwent concomitant left ventricular outflow tract (LVOT) closure at the time of continuous-flow left ventricular assist device (CF-LVAD) implantation. Although this technique of treating AI has been shown to be effective in the short term, its long-term durability has not been well studied. Here, we report the long-term outcomes of two patients with severe AI who underwent LVOT closure at the time of CF-LVAD implantation. Each of the two patients survived for more than 6xa0years without any complications related to LVOT closure.

Preoperative Prealbumin Level as a Predictor of Outcomes in Patients Who Underwent Left Ventricular Assist Device Implantation

Malnutrition has been associated with an increased risk of morbidity and mortality in patients who undergo cardiac surgery. However, many measurements of malnutrition have been inadequate prognostic markers. In this study, we sought to determine whether low preoperative serum prealbumin level was associated with morbidity and mortality in patients who underwent continuous-flow left ventricular assist device (CF-LVAD) implantation. From November 2003 to March 2016, 526 patients with chronic heart failure underwent implantation of a CF-LVAD (HeartMate II, nu2009=u2009403; HeartWare HVAD, nu2009=u2009123). Our cohort comprised the 317 CF-LVAD recipients whose records included the preoperative serum prealbumin level. These patients were divided into 2 groups: those with a normal preoperative serum prealbumin level (>17u2009g/dL) and those with hypoprealbuminemia (≤17u2009g/dL). These groups were then compared with regard to preoperative demographics, incidence of postoperative complications, long-term survival rate, and cause of death. Kaplan-Meier survival analysis revealed that patients with a low preoperative prealbumin level had significantly decreased survival rates at 1, 6, 12, and 24 months (pu2009<0.001) after CF-LVAD implantation and higher overall mortality (pu2009=u20090.04) than the patients with a normal prealbumin level, and that exacerbated heart failure made up the majority of this difference within the first 6 months. However, we found no significant correlations between low prealbumin level and postoperative complications. In conclusion, our findings demonstrate that preoperative serum prealbumin levels predict patient outcomes after CF-LVAD implantation.

Device Exchange: THI Technique Involving a Left Subcostal Approach

For patients with end-stage heart failure, continuous-flow left ventricular assist devices (CF-LVADs) have become more widely used, and the average duration of CF-LVAD support has lengthened. For this reason, the incidence of pump dysfunction necessitating pump exchange has increased. If pump dysfunction is due to pump failure or a driveline issue, isolated pump replacement can be performed. We have developed a quick and safe pump-exchange technique that avoids a redo sternotomy and the need for cardiopulmonary bypass. We have used this technique to replace malfunctioning HeartMate II CF-LVAD pumps. The patients are extubated within 3–6 h, and blood loss and transfusion requirements are generally minimal.

Predictive value of preoperative serum albumin levels on outcomes in patients undergoing LVAD implantation

We performed a single‐center retrospective analysis to determine whether preoperative serum albumin levels were associated with postoperative adverse events and short‐ and long‐term survival in patients who underwent continuous‐flow left ventricular assist device (CF‐LVAD) implantation.

Effect of concomitant mitral valve procedures for severe mitral regurgitation during left ventricular assist device implantation

The effect of performing a concomitant mitral valve procedure (MVP) during continuous-flow left ventricular assist device (CF-LVAD) implantation has been reported for patients with moderate-to-severe mitral regurgitation (MR), but moderate MR is less of a clinical concern for CF-LVAD patients. There is a paucity of reports focusing on patients with severe MR. Thus, the purpose of this study was to analyze the effect of performing a concomitant MVP during CF-LVAD implantation in patients with severe preoperative MR. Between November 2003 and March 2016, 526 patients underwent primary implantation of a CF-LVAD at our center. Patients with severe MR who underwent a concomitant MVP were compared to those who did not in regard to overall survival, perioperative complications, postoperative echocardiography data, bridge-to-transplantation success, and CF-LVAD explantation. Of the 108 patients with severe MR, 26 underwent a concomitant MVP and 82 did not. These groups showed no difference in survival (pu2009=u20090.61). Additionally, the two groups had similar rates of postoperative right heart failure (pu2009=u20090.69) and readmissions (pu2009=u20090.42). The 24-month follow-up echocardiography results were also similar. Furthermore, the groups showed no difference in bridge-to-cardiac transplantation success (30.0% vs 25.0%, pu2009=u20090.80) or CF-LVAD explantation rates (0.0% vs 0.0%. pu2009=u20091.0). Our findings suggest that patients with severe MR who undergo a MVP during CF-LVAD implantation do not have superior outcomes to those who do not. However, assessments of other outcomes may show some benefits to performing concomitant MVPs.

HeartMate II implantation technique that spares the sternum and ascending aorta

Left ventricular assist devices (LVADs) have become the standard therapy for patients with end-stage heart failure, and the use of LVADs for long-term support has grown exponentially over the past decade. As the number of LVAD implantations has increased, surgeons have faced more challenging cases, such as those in which the patient has previously undergone a sternotomy. The HeartMate II is one of the most widely implanted LVADs. The standard procedure for HeartMate II implantation is median sternotomy and sewing the outflow graft to the ascending aorta. However, in patients with sternal comorbidities, it can be advantageous to use a less invasive approach that avoids this procedure. We describe the case of a 64-year-old man with a history of end-stage ischemic cardiomyopathy who had previously undergone a median sternotomy and a coronary artery bypass grafting operation and had patent grafts. He required a HeartMate II LVAD (destination therapy), which was implanted via a left subcostal incision; the pump was placed subdiaphragmatically, and the outflow graft was sewed to the descending aorta to avoid a complicated redo cardiac operation via median sternotomy and to minimize the risk of injuring the patent bypass grafts. The patient survived for more than 500xa0days postoperatively. This approach is feasible and could be a safer method for implanting a HeartMate II device in patients with serious comorbidities that preclude the use of the traditional implantation techniques.

Outcomes in patients with advanced heart failure and small body size undergoing continuous-flow left ventricular assist device implantation

Left ventricular assist devices (LVADs) have become a preferred treatment option for patients with end-stage heart failure when used as a bridge to transplant or as a destination therapy. However, the association between small body size and postoperative outcomes for continuous-flow (CF) LVAD recipients is still being studied. We sought to determine whether body surface area (BSA) is associated with patient outcomes after CF-LVAD implantation. The study cohort of our single-center, retrospective review consisted of all patients (nu2009=u2009526) who underwent CF-LVAD implantation (nu2009=u2009403 HeartMate II, nu2009=u2009123 HeartWare) between November 2003 and March 2016 regardless of indication. Patients were stratified into 2 cohorts according to their BSA measurements: small BSA (<1.5xa0m2, nu2009=u200913) and non-small BSA (≥1.5xa0m2, nu2009=u2009513). We compared the survival of the small-BSA cohort with that of the non-small-BSA cohort. Patients with a small BSA had lower survival rates at 1, 6, 12, and 24xa0months (76.9, 61.5, 53.8, and 38.5%, respectively) than did patients with a non-small BSA (90.4, 80.9, 74.7, and 67.6% respectively; overall, pu2009=u20090.004). Cox proportional hazard analysis showed that a small BSA was an independent predictor of postoperative mortality (hazard ratiou2009=u20090.22, 95% confidence intervalu2009=u20090.05–0.97, pu2009<u20090.04). These findings highlight the adverse impact of a small BSA on outcomes after CF-LVAD implantation.

Acute kidney injury after implantation of a left ventricular assist device: a comparison of axial-flow (HeartMate II) and centrifugal-flow (HeartWare HVAD) devices

Continuous-flow left ventricular assist devices (CF-LVADs) are increasingly being used to treat advanced, refractory chronic heart failure. Herein, we sought to determine the incidence of postoperative acute kidney injury (AKI) in axial-flow (HeartMate II; HM-II) and centrifugal-flow (HVAD) CF-LVAD recipients, as well as the effect of AKI on mortality. The study cohort comprised 520 patients who received a HM-II (nu2009=u2009398) or HVAD (nu2009=u2009122) at our center between November 2003 and March 2016. Their records were reviewed to determine the incidence of RIFLE-defined AKI after LVAD implantation. We compared the perioperative characteristics, postoperative complications, and survival rates of the patients with and without AKI and differentiated the outcomes based on device type (HM-II or HVAD). Seventy-five patients (14.4%) developed AKI postoperatively. Patients with AKI after LVAD implantation had significantly reduced survival compared to patients without AKI (pu2009=u20090.01). Cox proportional hazards models showed that AKI was a significant independent predictor of mortality (HRu2009=u20091.54, pu2009=u20090.03). Preoperative mechanical circulatory support and prolonged cardiopulmonary bypass time were independent predictors of AKI. The incidence of AKI was similar for HM-II and HVAD recipients (pu2009=u20090.25). There was no significant difference in AKI rates for the HM-II and HVAD recipients. Developing AKI adversely affected survival.