Evolution of heart transplant donor characteristics in the 21st century: A United States single center's experience.

Despite a record setting number of heart transplants performed annually, the national donor shortage continues to plague transplant teams across the United States. Here we describe the barriers to adaptation of numerous "non-traditional" orthotopic heart transplant donor characteristics including donors with hepatitis C virus, those meeting criteria for donation after cardiac death, donors with coronavirus disease 19 infection, donors with the human immunodeficiency virus, and grafts with left ventricular systolic dysfunction. Our center's objective was to increase our transplant volume by expanding our donor pool from "traditional" donors to these "non-traditional" donors. We detail how medical advances such as certain laboratory studies, pharmacologic interventions, and organ care systems have allowed our center to expand the donor pool thereby increasing transplantation volume without adverse effects on outcomes.

Use of Extracorporeal Membrane Oxygenation for Primary Graft Dysfunction After Cardiac Transplantation: Results of an A Priori Ventless Approach.

Primary graft dysfunction (PGD) after cardiac transplantation is a devastating complication with increasing frequency lately in the setting of donation after circulatory death (DCD). Severe PGD is commonly treated with extracorporeal membrane oxygenation (ECMO) using central or peripheral cannulation. We retrospectively reviewed the outcomes of PGD after cardiac transplantation requiring ECMO support at our center from 2015 to 2020, focused on our now preferential approach using peripheral cannulation without a priori venting. During the study period, 255 patients underwent heart transplantation at our center and 26 (10.2%) of them required ECMO for PGD. Of 24 patients cannulated peripherally 19 (79%) were alive at 30 days and 17 (71%) 1 year after transplant; two additional patients underwent central ECMO cannulation due to unfavorable size of femoral vessels and concern for limb ischemia. Successful decannulation with full graft function recovery occurred in 22 of 24 (92%) patients cannulated peripherally. Six of them had an indwelling intra-aortic balloon pump placed before the transplantation. None of the other 18 patients received a ventricular vent. In conclusion, the use of an a priori peripheral and ventless ECMO approach in patients with PGD after heart transplant is an effective strategy associated with high rates of graft recovery and survival.

Lower limb amputation following venous cannulation for VA-ECMO: a case report.

Lower limb amputation following arterial cannulation for VA-ECMO has been described in the literature. Limb ischemia however following venous cannulation is very rare and not quite understood. We present a case of limb ischemia following venous cannulation. A combination of venous congestion, compartment syndrome and subsequent arterial insufficiency is the proposed pathophysiology. Shock and use of vasopressors are compounding factors. Limb ischemia can be transient and reversible if diagnosed immediately and treated by early removal of the cannula. Our patient was unstable and ECMO dependent, and removal of the cannula was not an option. This resulted in limb loss and eventual above knee amputation. Use of the smallest appropriate venous cannula and early fasciotomy, in addition to hemodynamic optimization are measures that could help in preventing major amputation.

Initiating a Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Endarterectomy Program Based on a Single Center Experience in Lebanon.

PURPOSE: In 2018, the American University of Beirut Medical Center established the first multidisciplinary Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Endarterectomy program in Lebanon. The study describes the challenges faced in establishing the program and in improving patient referral, evaluation, and perioperative care. METHODS: The program establishment including the preparation phase, clinical evaluation, and team education is discussed. The implementation of the flow of patients referred to the program was established. Education regarding diagnosis and referral were provided to physicians in the community. The initial experience is described in a retrospective analysis of 4 consecutive patients who were diagnosed with CTEPH and underwent PEA. RESULTS: Four patients were diagnosed with CTEPH had PEA performed. The mean age of patients was 64 years. The average CPB and total circulatory arrest times were 244 and 23.9 minutes per side, respectively. No mortalities were encountered perio-operatively. All patients reported significant improvement in functional capacity from NYHA III and IV to a NYHA class of I with an average PASP decrease of 59.5 ± 19.7 mmHg and mPAP drop by 30.2 ± 16.3 mmHg. CONCLUSION: The launch of the first CTEPH and PEA program in Lebanon, with a clear framework, coupled with good surgical outcomes is very encouraging. The program offers a curative solution for CTEPH patients in the region. A clear referral process and an increase in disease and treatment awareness in the community are crucial to the future success of the program, offering a definitive treatment, and avoiding delays to surgery.

Management of a mechanical aortic valve during left ventricular assist device implantation in a previously replaced aortic root.

The use of left ventricular assist device (LVAD) in patients with mechanical aortic valves may result in thromboembolic events due to blood stasis around the valve and intermittent valve opening. Mechanical aortic valves encountered during LVAD implantation are managed by replacement with a tissue valve, or closure of the valve with a patch. Closure of the valve carries the risk of sudden death in cases of LVAD stoppage. Replacing the whole mechanical valve conduit is time consuming and carries a significant risk of bleeding and right ventricular (RV) failure. We describe an alternative technique of replacing a mechanical aortic valve by breaking its inner leaflets and sewing a tissue valve on top of the mechanical valve ring.

Operative strokes after repair of acute type A dissections: predisposing factors and implications.

BACKGROUND: Type A aortic dissection is a surgical emergency with a high morbidity and mortality. Strokes occur in up to 25% and are among the most feared complications. This study aims to evaluate factors linked to stroke development and the implications of strokes on outcomes. METHODS: Patients from 2000-2014 were stratified based on the development of stroke. Factors were compared between the groups using chi-square or Fisher's exact tests for categorical variables, and independent two-group t-tests for continuous variables. Impact on survival at 30 days, 1 and 5 years were evaluated using the life-test method. RESULTS: Two hundred patients were analyzed. Forty (20%) developed a stroke. Preoperative factors associated with stroke were female gender (34% vs. 14% P=0.01), presentation with shock (32% vs. 17%; P=0.035), and history of stroke (64% vs. 17%; P<0.001). Femoral cannulation was the only technical variable associated with stroke (49% vs. 32%; P=0.035). Stroke patients had a higher rate of pneumonia (41% vs. 11%; P<0.001), respiratory failure (36% vs. 7%; P<0.001), hemodialysis requirement (38% vs. 16%; P=0.015), and longer hospital stay (23.9±17.8 days vs. 16.1±13.5 days; P=0.012). Stroke was associated with a lower survival probability at 30 days (0.73 vs. 0.89), 1 year (0.56 vs. 0.78), and 5 years (0.29 vs. 0.70) (P<0.001). CONCLUSIONS: Patients who developed stroke after type A dissection repair had higher complication rates and a higher mortality rate at 30 days, 1 year, and 5 years. Femoral cannulation was the only technical factor associated with a higher rate of strokes.

Transcatheter Aortic Valve Replacement: Comparing Transfemoral, Transcarotid, and Transcaval Access.

BACKGROUND: Despite newer-generation valves using smaller-sized sheaths, 10% to 20% of patients undergoing transcatheter aortic valve replacement (TAVR) require nonfemoral artery access for valve delivery. To avoid a transthoracic procedure, we have used transcarotid (TC) and transcaval (TCav) approaches in these patients. This study compared the results of a contemporary experience with transfemoral (TF), TC, and TCav approaches. METHODS: Between January 2015 and March 2017, 491 patients underwent TAVR at our institution, of which 463 were included in this analysis. Valve delivery was TF in 373 patients, TCav in 58, and TC in 32. Patient characteristics and outcomes, including 1-year survival, were compared. RESULTS: Preoperative demographics and postoperative outcomes were similar for the three groups with several exceptions. TCav patients had higher The Society of Thoracic Surgeons risk score than TF patients (8.0 ± 5.2 vs 6.1 ± 4.3, p = 0.004). Lung disease, cerebrovascular disease, and peripheral vascular disease were more common in TC and TCav patients. Median length of stay was 2 days for TF, 3 days for TC, and 4 days for TCav (TF vs TCav, p = 0.001). Procedural mortality, percentage discharged home, and the 30-day readmission rate were similar for all. Unadjusted Kaplan-Meier survival was also similar at 1 year (TF, 86%; TC, 83%; TCav, 80%). CONCLUSIONS: Patients unsuitable for TF TAVR treated with TC or TCav access had 30-day/in-hospital and 1-year survival similar to a contemporary cohort undergoing TF access. Avoiding surgical entry to the chest may offer procedural and intermediate-term outcomes equivalent to TF TAVR.

Resolution of Mitral Regurgitation With Left Ventricular Assist Device Support.

BACKGROUND: Cardiac valve disease is common in patients with end-stage heart failure undergoing left ventricular assist device implantation (LVAD). The aim of this study was to determine if preoperative mitral regurgitation (MR) affects outcomes and hemodynamics in patients after LVAD implantation. METHODS: From March 2006 through May 2015, 238 consecutive patients underwent LVAD implantation. Patient cohorts included less than moderate to severe MR (< moderate-severe, n = 195) and greater than or equal to moderate to severe MR (≥ moderate-severe, n = 43). Demographics, operative characteristics, postoperative outcomes, hemodynamic and echocardiographic data, and resolution of MR were compared at 30 and 180 days post-LVAD. RESULTS: Significant hemodynamic improvements were seen in central venous pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, cardiac index, left ventricular ejection fraction, and left ventricular end-diastolic diameter, irrespective of preoperative MR severity. Significant resolution of MR occurred across both cohorts, with only 4 of 168 (2.4%) patients with ≥ moderate-severe MR at 180 days post-LVAD. There were no differences in complications or survival between MR severity cohorts postoperatively. CONCLUSIONS: LVAD implantation unloads the left ventricle to promote left ventricle reverse remodeling and correct functional MR across all severity levels. The resolution of MR is sustained at 180 days post-LVAD. These results coupled with no survival difference with uncorrected MR between < moderate-severe MR and ≥ moderate-severe MR makes concomitant mitral valve repair or replacement at the time of LVAD implantation unnecessary.

Impact of Preoperative Atrial Fibrillation on Postoperative Thromboembolic Events After Left Ventricular Assist Device Implantation.

BACKGROUND: The incidence of atrial fibrillation (AF) among patients undergoing left ventricular assist device (LVAD) implantation is high. However, the impact of AF on clinical outcomes has not been clarified. We reviewed our 9-year experience of continuous flow (CF) LVADs to determine the impact of preoperative AF on stroke, device thrombosis, and survival. METHODS: Between March 2006 and May 2015, 231 patients underwent implantation of 240 CF LVADs, 127 (52.9%) as bridge to transplantation and 113 (47.1%) as destination therapy. Effect of AF on postoperative outcomes was assessed by using Kaplan-Meier survival and Cox proportional hazard regression. RESULTS: There were 78 patients (32.5%) with preoperative AF with a mean age of 55.7 ± 11.4 years. A similar incidence of stroke was found in patients with and without AF, 12.8% versus 16.0%, respectively (p = 0.803). Survival was similar, with 1-, 6-, 12-, and 24-month survivals of 96.2%, 91.7%, 84.5%, and 69.2%, respectively, for AF patients, versus 93.1%, 85.0%, 79.4%, and 74.1%, respectively, for non-AF patients (p = 0.424). Preoperative AF was not a significant independent predictor of survival with the use of Cox proportional hazard regression (hazard ratio 1.08, 95% confidence interval: 0.66 to 1.76). CONCLUSIONS: Preoperative AF was associated with a similar incidence of postoperative stroke, device thrombosis, and survival. On the basis of these data, it seems unnecessary to perform a left atrial appendage ligation or to alter postoperative anticoagulation in patients with AF undergoing LVAD implantation.

Socioeconomic disparities affect survival after aortic dissection.

OBJECTIVE: The effect of socioeconomic status (SES) on the course of many disease states has been documented in the literature but has not been studied in aortic dissection. This study evaluated the effect of SES on 30-day and long-term survival of patients after aortic dissection. METHODS: Hospital discharge records were used to identify patients with acute aortic dissection. Patient demographics, insurance status, comorbidities, and 30-day mortality were collected. Home addresses were used to estimate each patient's median household income, and the neighborhood deprivation index, a measure of SES, was determined. Long-term survival was assessed by review of the Social Security Death Index. Associations between demographics, insurance status, comorbidities, and poverty level were investigated to determine their effect on survival. RESULTS: There were 212 aortic dissections; of which, 118 were type A and 94 were type B. Median follow-up was 7.6 years. The neighborhood deprivation index (hazard ratio, 1.43; 95% confidence interval, 1.16-1.78; P = .001) was associated with reduced long-term survival and was also significantly associated with 30-day mortality (hazard ratio, 1.43; 95% confidence interval, 1.05-1.93; P = .02). The mean neighborhood deprivation index score was higher in patients with type B aortic dissections (0.45 ± 0.93) than in those with type A aortic dissections (0.16 ± 0.96; P = .029). CONCLUSIONS: Patients with a lower SES had reduced short-term and long-term survival after aortic dissection. Patients with type B dissection live in lower socioeconomic neighborhoods than patients with type A dissection.

Outcomes on Continuous Flow Left Ventricular Assist Devices: A Single Institutional 9-Year Experience.

BACKGROUND: Continuous-flow left ventricular assist devices (LVADs) have become the standard of care for patients with advanced heart failure. The goal of this study was to review our 9-year institutional experience. METHODS: From March 2006 through May 2015, 231 patients underwent implantation of 240 CF LVADs, HeartMate II LVAD (Thoratec Corp., Pleasanton, CA; n = 205) or HVAD (HeartWare Inc., Framingham, MA; n = 35). Of these, 127 devices (52.9%) were implanted as bridge to transplantation (BTT) and 113 (47.1%) as destination therapy (DT). RESULTS: Mean age was 51.2 ± 11.9 years for BTT patients and 58.2 ± 11.4 years for DT patients (p < 0.001). There was a higher incidence of preoperative diabetes, renal insufficiency, peripheral vascular disease, and previous cardiac operation in DT patients (p < 0.05). Survival was higher for BTT patients, with 1-, 6-, 12-, and 24-month survivals of 91.0%, 90.0%, 88.5%, and 72.1%, respectively, versus 85.3%, 81.1%, 75.6%, and 59.0%, respectively, for DT patients (p = 0.038). Gastrointestinal bleeding was the most common complication (29.6%), followed by right ventricular failure (22.5%) and stroke (15.0%), with a similar incidence for BTT and DT patients. Preoperative liver biopsy (hazard ratio [HR] 2.27, p = 0.036), mechanical support (HR 1.82, p = 0.025), aspartate transaminase (HR 1.07, p = 0.001), and alanine aminotransferase (HR 0.95, p = 0.024) were severe independent predictors of survival in multivariate analysis. CONCLUSIONS: These data indicate excellent survival for BTT and DT patients on long-term LVAD support. However, for LVAD therapy to become a plausible alternative to heart transplantation, we need to further decrease the incidence of postoperative complications.

Should Patients with Hepatic Fibrosis Undergo LVAD Implantation: A Comparative Analysis.

The purpose of our study was to evaluate outcomes in patients with hepatic fibrosis at the time of LVAD implantation. There were five (2.1%) patients with preoperative hepatic fibrosis with a mean age of 51.2 ± 16.8 years. Survival at 180 days was significantly reduced in patients with hepatic fibrosis, 40.0% vs. 88.0%; p = 0.001. Hepatic fibrosis was a significant independent predictor of mortality in multivariate analysis (hazard ratio [HR] 2.27, p = 0.036).

Effect of Body Mass Index on Outcomes in Left Ventricular Assist Device Recipients.

BACKGROUND AND AIM: Obesity is associated with higher mortality following heart transplantation, but there remains no consensus regarding outcomes in left ventricular assist device (LVAD) recipients. We sought to determine the impact of body mass index (BMI) on outcomes in patients undergoing LVAD implantation. METHODS: This was a single-institution retrospective review, including all patients who received a HeartMate II LVAD or HeartWare HVAD between March 2006 and June 2014. Patients were stratified into three groups based on normal (<25 kg/m(2) ), overweight (25-30 kg/m(2) ), and obese (>30 kg/m(2) ) BMI. RESULTS: Two hundred patients were included in the analysis. Mean BMI was 28.3 kg/m(2) , (27% normal, 36% overweight, and 36.5% obese). Obese patients were younger (51.9 years, p = 0.03) and had higher incidence of diabetes (58.9% vs. 24.1%; p < 0.001) and peripheral vascular disease (16.4% vs. 1.9%; p = 0.03). Normal BMI patients were more likely to undergo LVAD implantation as destination therapy compared to the overweight and obese groups (67% vs. 39% vs. 51%; p = 0.01) and had higher incidence of postoperative stroke/transient ischemic attack (22.2% vs. 6.9% vs. 12.3%; p = 0.04) and postoperative bleeding requiring reoperation (27.8% vs. 12.5% vs. 9.6%; p = 0.01). Survival at one, three, and five years was similar across all BMI groups. BMI was not an independent predictor of overall survival. CONCLUSIONS: Appropriately-selected patients at the extremes of BMI can safely undergo LVAD implantation with no difference in survival. BMI should not in itself be considered a contraindication to LVAD placement.

Short and long term outcomes of 200 patients supported by continuous-flow left ventricular assist devices.

AIM: To study the institutional experience over 8 years with 200 continuous-flow (CF) - left ventricular assist devices (LVAD). METHODS: We evaluated our institution's LVAD database and analyzed all patients who received a CF LVAD as a bridge to transplant (BTT) or destination therapy from March 2006 until June 2014. We identified 200 patients, of which 179 were implanted with a HeartMate II device (Thoratec Corp., Pleasanton, CA) and 21 received a Heartware HVAD (HeartWare Inc., Framingham, MA). RESULTS: The mean age of our LVAD recipients was 59.3 years (range 17-81), 76% (152/200) were males, and 49% were implanted for the indication of BTT. The survival rate for our LVAD patients at 30 d, 6 mo, 12 mo, 2 years, 3 years, and 4 years was 94%, 86%, 78%, 71%, 62% and 45% respectively. The mean duration of LVAD support was 581 d (range 2-2595 d). Gastrointestinal bleeding (was the most common adverse event (43/200, 21%), followed by right ventricular failure (38/200, 19%), stroke (31/200, 15%), re exploration for bleeding (31/200, 15%), ventilator dependent respiratory failure (19/200, 9%) and pneumonia (15/200, 7%). Our driveline infection rate was 7%. Pump thrombosis occurred in 6% of patients. Device exchanged was needed in 6% of patients. On multivariate analysis, preoperative liver dysfunction, ventilator dependent respiratory failure, tracheostomy and right ventricular failure requiring right ventricular assist device support were significant predictors of post LVAD survival. CONCLUSION: Short and long term survival for patients on LVAD support are excellent, although outcomes still remain inferior compared to heart transplantation. The incidence of driveline infections, pump thrombosis and pump exchange have declined significantly in recent years.

Effect of Preoperative Albumin Levels on Outcomes in Patients Undergoing Left Ventricular Device Implantation.

Hypoalbuminemia is a well-known predictor of morbidity and mortality in cardiac surgery. Our aim was to establish the impact of serum albumin on outcomes after left ventricular assist device (LVAD) implantation. This was a single-institution retrospective review, including all patients who underwent LVAD implantation between March 2006 and June 2014. Two hundred patients were included in the analysis. Mean serum albumin was 3.27 ± 0.47 g/dl, with 7% in the low albumin group (<2.5 mg/dl), 67.5% in the mid-range (2.5-3.5 mg/dl), and 25.5% in the normal albumin groups (> 3.5 mg/dl). Lower albumin was associated with a significant increase in postoperative renal failure (42.9 vs. 16.5 vs. 17.3%; p = 0.05) and prolonged hospitalization (median 28.5 vs. 16 vs. 15.5 days; p = 0.008). Six month, 1 year, and 5 year survival was 79%, 79%, and 49% with low, 84%, 78%, and 51% with mid-range, and 94%, 88%, and 60% with normal albumin, respectively (p = 0.22). Preoperative hypoalbuminemia is associated with postoperative acute renal failure (ARF) and prolonged hospitalization after LVAD implantation, with no effect on overall survival. Hypoalbuminemia is most likely a marker of advanced disease and should not, in itself, be considered a contraindication to LVAD candidacy.

Outcomes of patients with right ventricular failure on milrinone after left ventricular assist device implantation.

Previous studies have grouped together both patients requiring right ventricular assist devices (RVADs) with patients requiring prolonged milrinone therapy after left ventricular assist device (LVAD) implantation. We retrospectively identified 149 patients receiving LVADs and 18 (12.1%) of which developed right ventricular (RV) failure. We then separated these patients into those requiring RVADs versus prolonged milrinone therapy. This included 10 patients who were treated with prolonged milrinone and eight patients who underwent RVAD placement. Overall, the RV failure group had worse survival compared with the non-RV failure cohort (p = 0.038). However, this was only for the subgroup of patients who required RVADs, who had a 1, 6, 12, and 24 month survival of 62.5%, 37.5%, 37.5%, and 37.5%, respectively, versus 96.8%, 92.1%, 86.7%, and 84.4% for patients without RV failure (p < 0.001). Patients treated with prolonged milrinone therapy for RV failure had similar survivals compared with patients without RV failure. In the RV failure group, age, preoperative renal failure, and previous cardiac surgery were predictors of the need for prolonged postoperative milrinone. As LVADs become a more widely used therapy for patients with refractory, end-stage heart failure, it will be important to reduce the incidence of RV failure, as it yields significant morbidity and increases cost.

Lessons learned from 150 continuous-flow left ventricular assist devices: a single institutional 7 year experience.

Continuous-flow (CF) left ventricular assist devices (LVADs) have become the standard of care for patients with advanced heart failure refractory to optimal medical therapy. The goal of this study was to review our 7 year single institutional experience with CF LVADs. Mean age was 50.4 + 12.5 (17-69) years for bridge-to-transplantation (BTT) patients and 57.6 + 10.4 (31-81) years for destination therapy (DT) patients (p < 0.001). Overall, 38 patients (26%) were female and 58 (41%) were African American. Etiology of heart failure was ischemic in 54 patients (37%) and nonischemic in 93 patients (63%). Overall survival at 30 days, 6 months, 12 months, and 2 years was 93%, 89%, 84%, and 81%, respectively. Gastrointestinal bleeding (GIB) was the most common complication (24%), followed by stroke (18%), right ventricular (RV) failure (18%), ventilator-dependent respiratory failure (10%), reoperation for bleeding (10%), and driveline infection (9%). These data demonstrate excellent survival with low mortality for both BTT and DT patients on long-term LVAD support. However, for LVAD therapy to become the gold standard for long-term treatment of end-stage heart failure and a plausible alternative to heart transplantation, we need to continue to improve the incidence of frequent postoperative complications, such as RV failure, driveline infections, strokes, and GIB.