Percutaneous Intervention in External Outflow Graft Obstruction of Magnetically Levitated Left Ventricular Assist Device: Long-Term Follow-Up and Quality of Life.

Mechanical circulatory support: Technical tips for the implantation of a right ventricular assist device

Left ventricular assist devices (LVADs) are an established treatment for patients with end-stage heart failure as either a bridge to cardiac transplantation1 or as lifelong support, also known as destination therapy.2 The HeartMate II (HM II) LVAD (Thoratec Corporation, Pleasanton, CA) is a continuous-flow device that was approved by the US Food and Drug Administration in 2008, after a pivotal trial in 133 patients awaiting transplantation.3 More patients have been implanted with the HM II than any other durable LVAD. Actuarial survival with continuous-flow LVADs has improved to 80% at 1 year and 70% at 2 years, leading to a growing population of patients with heart failure living with long-term mechanical circulatory support.4 The HM II titanium axial flow rotary pump is placed in the abdominal musculature or within a preperitoneal pocket in the left upper quadrant. Blood enters the LVAD via an inflow cannula at the LV apex and exits through an outflow cannula connected via a graft to the ascending aorta. The outflow bend relief is a polytetrafluoroethylene tube at the junction of the outflow cannula and the pump housing designed to prevent kinking of the outflow cannula. In February 2010, Thoratec modified the outflow cannula bend relief with a snap ring design that allowed disconnection of the bend relief to facilitate assessment of the underlying cannula for bleeding or malposition. Between February 2010 and February 2012, the manufacturer distributed >3800 modified outflow cannula bend reliefs to 226 hospitals and distributors worldwide. In April 2012, the US Food and Drug Administration issued a class I recall for the HM II LVAD after reports of disconnection of the bend relief from the outflow grafts.5 The initial reported worldwide incidence of disconnected outflow graft bend reliefs was 0.75% (29 of 3852 patients), with 1 death …

Background: Innovations in left ventricular assist device (LVAD) technology have led to improved survival with less complications, however external outflow graft obstruction (EOGO) has been recognized as a new complication. EOGO occurs when fibrinous materials collect between the LVAD outflow graft, due to its porous nature, and bend relief cover. This collection compresses the graft and can cause low flow alarms and worsening heart failure. Consensus on management of EOGO has not been established. For patients with suspected EOGO, what diagnostic modalities should be utilized and what interventions should be considered? Description of case: A 54-year-old man with an LVAD was admitted for recurrent low flow alarms. Transthoracic echocardiogram (TTE) demonstrated a dilated left ventricle (LV) at 6cm, and ejection fraction of 21%. Computed tomography angiogram (CTA) showed stenosis in the proximal outflow graft near the pump housing. Endovascular approach, LVAD exchange, and graft repair were all considered, however he was listed for heart transplant. Prior to transplant, he developed cardiogenic shock with persistent low flow alarms. Repeat CTA showed extension of the outflow obstruction. He underwent mini thoracotomy, the space between the outflow graft and bend relief was fenestrated, and a yellow proteinaceous material gushed out. The outflow graft immediately expanded with improvement of LVAD flows. Discussion: EOGO should be considered in LVAD patients with recurrent low flow alarms. Multimodality imaging is vital to determine etiology and location of obstruction. On TTE, obstruction should be suspected if there is worsening LV dilation and mitral regurgitation. CTA is recommended as it allows visualization and localization of outflow graft obstruction. If obstruction is distal to the LVAD pump (near the aorta) endovascular approaches (stenting or balloon angioplasty) can be considered. If proximal to the pump housing, endovascular approaches may pose higher risk and surgery should be considered. Surgical interventions include relief of the obstruction by fenestrations in the bend relief, pump exchange, or even heart transplant. Given our patient's EOGO was proximal to the pump housing, endovascular approaches were not attempted. In summary, EOGO can be thoroughly evaluated with multimodality imaging including echocardiogram and CTA. CTA is imperative to evaluate severity and location of obstruction, guiding appropriate treatments strategies.

Long-Term Quality of Life (QOL) After Chemo-IMRT for Locally Advanced Oropharyngeal Cancer (OPC): A Prospective Longitudinal Study

Second INTERMACS annual report: More than 1,000 primary left ventricular assist device implants

In 2019, a 42-year-old man underwent implantation of a HeartMate 3 left ventricular assist device (LVAD) as a bridge to transplantation for end-stage heart failure. In January 2023, he complained of occasional lightheadedness. Left ventricular assist device parameters were stable with a rate of 5,500 rpm, flow of 4.1 L/m, pulse index of 5.6, and power of 4 W. Echocardiography showed mild aortic regurgitation with stable ventricular dimensions. Computed tomography (CT) angiography was performed to evaluate the inflow and outflow graft. Outflow graft stenosis (OGS) causing approximately 45% obstruction was noted (Figure 1), probably due to external compression of the outflow graft in the “bend relief,” which is a stiff polytetrafluoroethylene covering. Given the mild severity of symptoms and normal LVAD parameters, watchful waiting was continued. CT angiography repeated 6 months later showed no change in stenosis severity. In March 2024, the patient underwent heart transplantation with LVAD explantation. Close examination of the outflow graft revealed OGS due to fibrofatty material within the bend relief (Figure 2). Microscopic evaluation of the material on hematoxylin–eosin (H&E)–stained slides was consistent with the deposition of an extensive amount of amorphous eosinophilic material without the prominent presence of inflammatory cells (Figure 3).Figure 1.: A: A CT angiography image showing a horizontal section of the outflow graft with stenosis due to biological material accumulation between the graft and the bend relief. B: Sagittal section of the outflow graft showing partial luminal stenosis. CT, Computed tomography.Figure 2.: A: Horizontal section of the outflow graft showing accumulation of biological material between the outflow graft and the bend relief. B: Dissection of the bend relief shows extensive accumulation of biological material covering the graft. C: Both the outflow graft and the bend relief are dissected and deformation of the lumen due to external compression of the biologic material is seen. D: Lateral view of the graft shows the accumulated fibrofatty biologic material and aneurysmal dilatation of the bend relief at the site of the accumulated biologic material.Figure 3.: A: The material shows amorphous homogeneous eosinophilic staining in H&E stain and does not contain prominent aggregates of inflammatory cells. B: Higher magnification shows rare inflammatory cells including lymphocytes (arrowhead) and histiocytes (arrow). H&E, hematoxylin–eosin.Outflow graft stenosis is a newly recognized serious complication of permanent LVAD support with HeartMate 3. A recent multicenter study reported an increasing incidence of OGS from 0.6% at 1 year to 9.1% at 5 years. Outflow graft stenosis may develop due to intraluminal formation of amorphous protein-like material with subsequent external obstruction, probably due to chronic organic material leaking through the graft and accumulating between the graft and the bend relief.1 The management approach is not yet established, but asymptomatic patients with <50% stenosis could be followed closely, while intervention should be considered in symptomatic cases with OGS >50% to 75%.2 Percutaneous stenting seems to be preferable to surgical approaches.3

Intraoperative Use of Vascular Ultrasound to Localize Thrombus in Left Ventricular Assist Device Exchange.

LVAD Outflow Graft Stenosis

Thrombus detected in computed tomography angiography images of HeartMate II outflow graft: A cautionary tale

The benefits of left ventricular assist device (LVAD) therapy in advanced heart failure are clear—device implantation can prolong patient survival, enhance functionality, and improve quality of life.1 Since US Food and Drug Administration approval of the first continuous-flow LVAD in 2008, utilization has grown rapidly, and now, >2500 devices are placed annually.1 Given the current epidemic of heart failure, this volume may only be scratching the surface. Current estimates suggest that there are upwards of 250 000 to 300 000 potential LVAD candidates in the United States alone.2 Despite technological and design advances, broader application of LVAD therapy remains limited in part by its relatively high rate of adverse events (AEs). Six-month freedom from rehospitalization is only 40%, whereas 70% of patients will experience an AE within the first year of support.1 See Article by Levin et al In this issue of Circulation : Heart Failure , Levin et al retrospectively described hemolytic events of HeartMate II (St. Jude Medical, Pleasanton, CA) patients at 2 large academic medical centers. Specifically, they compared outcomes for patients with hemolysis managed with surgical versus medical therapy, to determine the most effective strategy.3 Their findings were humbling. One-year freedom from stroke or death was 87.5% and 49.5% in the surgical and medical cohorts, respectively. Resolution of primary hemolysis without stroke, death, or recurrent hemolysis was only 44% in patients treated with medical therapy, compared to 63% in patients treated operatively. Even more sobering is the realization that the surgical cohort first failed medical therapy, and thus, the true treatment response to medical therapy alone was a paltry 29%. In summary, the principal finding was that for patients meeting the author’s definition of hemolysis, a surgical strategy (after failed medical intervention) resulted in less death or stroke than a medical strategy alone, …

A multicenter evaluation of external outflow graft obstruction with a fully magnetically levitated left ventricular assist device

Background: The HeartMate 3 (HM3, Abbott) left ventricular assist device (LVAD) is the only commercially available option considered suitable for long-term circulatory support. External compression of the outflow graft causing obstruction (eOGO) is a serious adverse event affecting patients on long-term support. The obstruction occurs due to the accumulation of gelatinous substance between the bend relief and outflow graft. This systematic review evaluated all available studies with regard to the diagnosis and therapy of eOGOs. Methods: A systematic literature review and analysis of individual patient data was performed using MEDLINE/PubMed following PRISMA guidelines. Original works dating up to 31 October 2024 were considered. Results: Twenty-four publications that met the inclusion criteria were identified, providing individual data from 113 patients with a median support time to eOGO diagnosis of 809 days [588, 1095] and follow-up after treatment of 365 days [33, 605]. eOGO severity classification was performed on 108 patients according to our grading system. For treatment, most patients underwent surgery (n = 38) or stenting (n = 29). A hazard ratio of 0.75 [0.28, 2.03] was calculated for the surgical group versus the stenting group (p = 0.570). Conclusions: Concerning 30-day mortality, we did not find a significant difference between the eOGO severity of survivors and non-survivors. We found no significant differences in outcome between patients with differing eOGO severity and treatment strategy, namely stenting and surgery. Due to an increase in eOGO incidence after one year of support, we propose that clinicians monitor their patients for this complication when support time surpasses one year.

Injury is a leading cause of death and preventable morbidity in adolescents. Little is known about long-term quality of life (QoL) outcomes in injured adolescents. The objectives of the present report are to describe long-term QoL outcomes and compare posttrauma QoL to national norms for QoL in uninjured adolescents from the National Health Interview Survey (NHIS). In all, 401 trauma patients aged 12 to 19 years were enrolled in the study. Enrollment criteria excluded spinal cord injury. QoL after trauma was measured using the Quality of Well-being (QWB) scale, a sensitive and well-validated functional index (range: 0 = death to 1.000 = optimum functioning). Patient outcomes were assessed at discharge, and 3, 6, 12, 18, and 24 months after discharge. NHIS data were based on 3 survey years and represent a population-based U.S. national random sample of uninjured adolescents. Major trauma in adolescents was associated with significant and marked deficits in QoL throughout the 24-month follow-up period, compared with NHIS norms for this age group. Compared with NHIS norms for QoL in uninjured adolescents aged 12 to 19 years (N = 81,216,835; QWB mean = 0.876), injured adolescents after major trauma had striking and significant QoL deficits beginning at 3-month follow-up (QWB mean = 0.694, p < 0.0001), that continued throughout the long-term follow-up 24 months after discharge (6-month follow-up QWB mean = 0.726, p < 0.0001; 12-month follow-up QWB mean = 0.747, p < 0.0001; 18-month follow-up QWB mean = 0.758, p < 0.0001; 24-month follow-up QWB mean = 0.766, p < 0.0001). QoL deficits were also strongly associated with age (>or=15 years) and female sex. Other significant risk factors for poor QoL outcomes were perceived threat to life, pedestrian struck mechanism, and Injury Severity Scores >16. Major trauma in adolescents is associated with significant and marked deficits in long-term QoL outcomes, compared with U.S. norms for healthy adolescents. Early identification and treatment of risk factors for poor long-term QoL outcomes must become an integral component of trauma care in mature trauma care systems.

68 Background: High-dose conformal proton radiation for localized prostate cancer results in favorable clinical outcomes and low toxicity rates. Here, we report long-term quality of life (QOL) outcome for men treated with conformal protons. Methods: Serial QOL questionnaires were administered to men who received proton radiation. Long-term questionnaires (minimum 2 years) were completed by 72 patients. Men were stratified into functional groups from their baseline questionnaires (normal, intermediate or poor function) for each symptom domain. Symptom scores were calculated at baseline and long-term follow-up and expressed as mean values. QOL changes were assessed overall and within functional groups in a paired fashion using the Student's t-test. Results: The median age at treatment and follow-up were 66 years and 44 months, respectively. The median dose was 82 GyE (range 74-82 GyE). For all 72 patients, there were increased scores for incontinence (ID) (3.2 baseline vs. 9.9 long-term, p=&lt;0.001), obstructive/irritative voiding (OID; 20 vs. 24, p=0.028), bowel (BD; 4.4 vs. 8.0, p=0.001) and sexual dysfunction (SD; 25 vs. 48, p&lt;0.001). When stratified by functional category, more specific estimates were possible. For ID, only normal function was associated with a significant increased score (0 vs. 8.4 at baseline and long-term, p=&lt;0.001); for OID, only the group with normal baseline function showed a significant increased score (12 vs. 17, p=0.01); similarly for BD, only men with normal function had a significant increased score (0 vs. 5.4, p&lt;0.001). For SD, the score increased in men with normal (1.4 vs. 30, p&lt;0.001) and intermediate function (17 vs. 46, p&lt;0.001). Conclusions: Patient reported outcomes are sensitive indicators of treatment related sequelae and here quantitate, for the first time, the long-term consequences of proton monotherapy for prostate cancer. Analysis by baseline functional category is a useful means of predicting long-term QOL scores for an individual patient. High-dose proton radiation was associated with small increases in bowel dysfunction, obstructive/irritative voiding dysfunction and incontinence. With long term follow-up, sexual dysfunction increased more than any other symptom domain. No significant financial relationships to disclose.

Left Ventricular Assist Device Outflow Graft Compression: Incidence, Clinical Associations and Potential Etiologies