Outcomes of modular cable exchange in HeartMate 3 patients versus conventional driveline repair in HeartMate II patients.

BACKGROUND: Driveline (DL) damages are a common difficulty among ventricular assist devices (VAD). Repairing the electrical fibers inside the DL on a running pump is hazardous and requires technical expertise, which is not easily available on site. A new feature of the HeartMate3 (Abbott, U.S.A.) LVAD is a modular driveline that allows an easy exchange of the DL cord. In this report we analyze our experiences with this feature. METHODS: We performed a retrospective analysis of 302 patients who underwent either HeartMate II or HeartMate 3 implantation between February 2004 and September 2021. Patients were screened for driveline faults and need for exchange or repair of driveline or VAD exchange. Documented were baseline characteristics, reasons for DL or VAD exchange, and complications. Follow-up was three months after the procedure. RESULTS: We present a cohort of 302 patients who underwent either HMII (n = 107;35.4%) or HM 3 (n = 195; 64.5%) implantation. Out of those, 40 patients (40/302; 13.2%) required driveline repair (DLRe) or exchange (DLEx). Out of 107 HMII patients, 9 showed severe DL damages (9/107; 8.4%). Six patients (6/9; 66.6%) underwent DLRe, two patients (2/6; 33.3%) required VAD exchange after DLRe, one patient (1/2;50%) experienced emergency VAD exchange after pump stop. The DLRe procedure in the other four patients (4/6; 66.6%) was successful. Due to damage to the internal driveline two patients (2/9; 22.2%) underwent emergency device exchange and one patient (1/9;11.1%) was listed for transplantation. 31 out 195 HM3 patients underwent exchange of the modular DL. In none of the cases, damages of the internal fibers were the reasons for the exchange. In 100% of the cases, damages of the external coating were the reason for DL exchange. In none of the cases, complications occurred after the exchange procedure. CONCLUSIONS: Driveline damages are a habitual, recurrent complication in VAD patients. The exchange of the modular driveline cable of the HM3 is feasible and safe compared to the conventional DL repair in HMII patients. Risky repair attempts and surgical LVAD exchange due to major damages of the electrical fibers can be avoided successfully by the new feature of HM3 driveline.

Is there a sex gap in outcomes of comparable patients supported with left ventricular assist devices?

OBJECTIVES: Historically, females were described as suffering from worse outcomes after left ventricular assist device (LVAD) implantation. However, females' preoperative conditions are unique, making direct comparisons with males challenging. This study aimed to select through propensity score (PS) matching two preoperatively comparable populations of females and males and test if any real sex-related difference exists regarding survival and adverse events after LVAD implantation. METHODS: This retrospective single-center observational study investigated patients who received LVAD implantation between 2010 and 2018. PS matching was applied to balance preoperative heterogeneity between males and females. Primary endpoint was survival at follow-up. Secondary endpoints included perioperative outcomes and LVAD-related adverse events. RESULTS: 92 fully comparable females(n = 46) and males(n = 46) were selected after PS matching (median age:57 years, min-max:18-75). 26.1% of patients required preoperative mechanical circulatory support. Females needed more intraoperative fresh frozen plasma (p < 0.001) and platelets transfusions (p = 0.008) compared to males, but postoperative outcomes were comparable between groups. In-hospital, 1 and 2-year survival were 78.3%, 69.6% and 65.2%, respectively, with no differences between groups. Survival probability remained comparable up to 8 years of follow-up (p = 0.35). Overall, females showed a higher rate of strokes (p = 0.039) compared to males in the follow-up time. CONCLUSIONS: After reducing preoperative heterogeneity between females and males, survival after LVAD implantation does not differ based on sex. However, differences might exist in terms of higher transfusions and strokes in females. Reducing preoperative sex disparities and developing intraoperative and anticoagulation strategies which acknowledge sex-related variations might help abolishing differences in LVAD outcomes.

Left ventricular assist device implantation in patients with left ventricular thrombus.

An intra-cavitary left ventricular (LV) thrombus is a relative contraindication to LV assist device (LVAD) implantation based on increased thromboembolic risks. Herein, we present our experience with LVAD patients with or without preoperative diagnosis of LV-thrombus. We retrospectively investigated 563 patients who received LVAD implantation between 2004 and 2018. Diagnosis of LV-thrombus was verified with computed tomography scan, magnetic resonance imaging, echocardiography, or intraoperative LV inspection. The primary endpoint was 30-day survival free of stroke and pump thrombosis. Overall, 72 patients (12.8%) had a diagnosis of LV-thrombus. They were younger (51 years; IQR:41-59), affected by severely reduced ejection fraction (15%; IQR:10-20), more often presenting with dilated cardiomyopathy (61.8%) and INTERMACS profile 1 (33.3%). Preoperative atrial fibrillation was frequent in patients without LV-thrombus (38.9%). Conventional sternotomy was the preferred approach in LV-thrombus patients (77.8%), based on more HMII implantations in these patients (41.7%). Survival free of strokes and pump thrombosis at 30 days was comparable (P = .5751) between patients with (83.3%) or without LV-thrombus (80.9%). LVAD implantation in patients with preoperative LV-thrombus is safe and feasible. When managed through correct diagnostic and intraoperative strategies including accurate inspection of the LV cavity, these patients show similar 30-day outcomes compared to patients without LV-thrombus.

Prophylactic mechanical circulatory support for protected ventricular tachycardia ablation: A meta-analysis of the literature.

Acute hemodynamic decompensation (AHD) during ventricular tachycardia (VT) ablation occurs in about 11% of cases. Prophylactic use of temporary mechanical circulatory support (pro-tMCS) has been applied to prevent AHD during VT ablation, but evidence supporting this practice is still lacking. This systematic review and meta-analysis assessed the procedural characteristics and outcomes of pro-tMCS for VT ablation. PubMed/Medline was screened until February 2020. Articles including adults receiving pro-tMCS for VT ablation were included, and a meta-analysis to compare proMCS and no-tMCS was performed. Primary outcome was in-hospital/30-day mortality. Five observational studies presenting 400 procedures (pro-tMCS: n = 187; no-tMCS: n = 213) were included. Baseline characteristics were comparable between groups. Impella and TandemHeart were used in 86.6% and 13.4% of cases, respectively. In the pro-tMCS group, more VTs were induced (mean difference: 0.52, confidence interval [CI]: 0.26-0.77, P < .0001), and patients remained in VT on average for 24.04 minutes longer (CI: 18.28-29.80, P < .00001). Procedural success was comparable between groups, as was VT recurrence. Pro-tMCS patients had an odds ratio of 0.55 (CI: 0.28-1.05, P = .07) for in-hospital/30-day mortality and 0.55 (CI: 0.32-0.94, P = .03) for mortality at follow-up. Sixty-four percent of no-tMCS patients received rescue tMCS. The most common tMCS-related complications were bleeding events. Pro-tMCS allowed for a prolonged time on VTs and the induction of more VTs. Although these advantages were not associated with differences in procedural success, VT recurrence, or in-hospital/30-day mortality in the overall population, pro-tMCS might improve long-term survival. Further prospective studies are urgently needed to confirm these results.

Flying after left ventricular assist device implantation.

Literature on the air travel activities of patients supported by permanent mechanical assist devices is rare. To the best of our knowledge, no air travel guidelines or fitness prerequisites exist on whether and when ventricular assist device (VAD) patients are allowed to travel by plane after device implantation. In this study, we evaluated the topic of air travel after VAD implantation. This working group aimed to produce a report on air travel passengers supported by VADs, regarding their fitness to fly. Fifty left ventricular assist device (LVAD) patients were surveyed in a worldwide multicenter study. The single survey was performed with a multimethod design, including interviews conducted face-to-face, online, and on phone. Out of 50 patients, 97% described their traveling by aircraft as perfect and uneventful during the flight. Eighty-five percent of the study participants consulted their medical practitioner before the flight. No patient reported the occurrence of a severe condition associated with flying. LVAD alarms, especially low flow alarms, did not occur in any of the devices. Thirty-five percent of the surveyed patients, however, stated a major problem pertaining to the security check procedures at the airport. The results of this study suggest that commercial air travel is safe for stable patients on permanent VAD support and traveling can be resumed securely after VAD implantation. Conscientious preparation by packing necessary devices, fluids, medications, and careful preparation for the airport security check is recommended.

Out of hospital management of LVAD patients during COVID-19 outbreak.

Coronavirus disease 2019 (COVID-19) is a pandemic touching thousands of people all around the world. Patients supported with left ventricular assist devices (LVADs) are affected by long-standing cardiovascular diseases and subjected to variations of the normal cardiovascular physiology, thus requiring an even closer monitoring during the COVID-19 outbreak. Nevertheless, the COVID-19 pandemic led to a drastic reduction in routine clinical activities and a consequent risk of looser connections between LVAD patients and their referring center. Potential deleterious effects of such a situation can be a delayed recognition of LVAD-related complications, misdiagnosis of COVID-19, and impaired social and psychological well-being for patients and families. As one of the largest LVAD programs worldwide, we designed a sustainable and enforceable telemonitoring algorithm which can be easily adapted to every LVAD center so as to maintain optimal quality of care for LVAD patients during the COVID-19 pandemic.

Driving After Left Ventricular Assist Device Implantation.

Literature on driving capacities of ventricular assist device patients is rare and driving restrictions differ from center to center. Currently, no guidelines exist on whether and when left ventricular assist device (LVAD) patients are allowed to begin driving cars after device implantation. In this study, we assess the driving abilities of patients after LVAD implantation. Three hundred and ninety LVAD patients have been surveyed in a worldwide, multicenter study. The single survey followed a multi-method design, including online, phone, and face-to-face interviews. Out of 390 patients, 72% are still driving and 28% did not continue driving after LVAD implantation. Reasons for discontinuation were capability (24%), insecurity (17%), and disapproval by family members (9%) or doctors (5%). Ninety percent of the patients describe their ability to drive as perfect or adequate. Sixty-nine percent state that they are not restricted in their general driving capacity. Forty-nine percent report not to be restricted in agility to drive by the device equipment. The majority of patients have not been involved in car accidents or major complications (94%). Eight accidents were reported (3%). Out of those, all were minor collisions. No patient reported the occurrence of a fatal accident or casualties. LVAD alarms did occur in six incidents (2%) with the majority being low battery alarms. The results of this study suggest that driving with a left ventricular assist device is safe for stable patients and driving can be resumed 3 months after LVAD implantation after careful patient assessment.

In Vitro Evaluation of Inflow Cannula Fixation Techniques in Left Ventricular Assist Device Surgery.

The therapy of terminal heart failure with left ventricular assist devices has become a standard in cardiac surgery. Yet the surgical implantation technique is not standardized and differs from center to center. Complications associated with left ventricular assist device (LVAD) inflow cannula placement are thrombosis, suction events, and flow disturbances. Within this in vitro study we aimed to investigate if the fixation technique of the sewing ring has an impact on the position of the inflow cannula. For this in vitro study the HeartMate III LVAD (Thoratec Corporation, Pleasanton, CA, USA) was used. In five sessions, two approaches were considered for coring of the ventricle for LVAD inflow cannula insertion: "sew-then-core" and "core-then-sew." In the "sew-then-core" technique, the sewing cuff is first affixed to the heart, usually with 8-16 interrupted pledgeted mattress sutures. Subsequently, a cylindrical knife is used to resect a cylindrical core of myocardium to permit cannula insertion. In the "core-then-sew" technique, the sequence is reversed such that the knife is used before the suture ring is affixed. When the "sew-then-core" technique is used, the mattress sutures may be placed with full-thickness bites that penetrate the endocardium (i.e., transmural stitching) or partial-thickness bites that do not penetrate the endocardium (i.e., epicardial stitching). When the "core-then-sew" technique is used, the suture is passed fully into the ventricular lumen and fed back through the cored hole, at which point the needle may be reinserted into the freshly cored myocardium such that it exits the epicardium (i.e., transmural stitching with back stitch) or not (i.e., transmural stitching without back stitch). These four different sewing ring fixation suturing techniques were tested by experienced surgeons to affix the sewing ring: transmural stitching, epicardial stitching, transmural stitching with back stitch, and transmural stitching without back stitch. The sewing ring was sewed onto a silicone dummy designed to simulate the left ventricle with standard 2-0 Ethibond sutures (Ethicon, Somerville, NY, USA). Afterward, the dummies were measured and documented via photography. In addition, porcine hearts were used to simulate the suturing techniques in a physiological setting. The setting of the inflow cannula is substantially influenced by the fixation method of the sewing ring. Epicardial stitching showed the best results with stable cannula fixation, minimal gap around the cannula and no contact between the sutures and sewing ring with blood. The method of transmural stitching without back stitch showed the worst results by creating the biggest epithelial gap between inflow cannula and tissue as well as proving the biggest surface for blood contact between sewing ring and sutures. In general, both "sew-then-core" techniques resulted in a greater degree of apposition between the cuff and epicardial tissue. Within the study we revealed that the surgical fixation of the sewing ring has a significant impact on the inflow cannula stability, position, and tissue apposition in LVAD implantation surgery. Epicardial stitching of the sewing ring provides the best results in order to prevent suction events as well as thrombosis formation.

Chronic ventricular assist device support: surgical innovation.

PURPOSE OF REVIEW: Ventricular assist device (VAD) therapy is currently one of the fastest-developing fields in cardiac surgery. Consistently improved technology, research, and gain of clinical experience have established VADs as an important option for the treatment of congestive heart failure. During the past year, novel devices and less invasive surgical procedures have been revolutionizing this field. The purpose of this manuscript is to review these innovations with special emphasis on device-related surgery. RECENT FINDINGS: Device miniaturization has enabled less invasive VAD surgery, excluding the need for full sternotomy. Recent data show that intrahospital survival rates following less invasive VAD implantation are surpassing 90%. Secondly, two new devices, Heartmate 3 and MVAD, are being applied and tested for clinical application. In this context, the Heartmate 3 CE mark study recently concluded with excellent outcomes and without any pump thrombosis or device malfunctions. SUMMARY: The first clinical results of the newest generation of VADs are very promising compared with old-generation devices. Furthermore, less invasive surgery is becoming a standard for the implantation, exchange, or explantation of left VADs. The joint venture of improved technology and innovative surgical techniques will push this field forward to even better outcomes and reduced complication rates.

Minimally invasive ventricular assist device surgery.

The use of mechanical circulatory support to treat patients with congestive heart failure has grown enormously, recently surpassing the number of annual heart transplants worldwide. The current generation of left ventricular assist devices (LVADs), as compared with older devices, is characterized by improved technologies and reduced size. The result is that minimally invasive surgery is now possible for the implantation, explantation, and exchange of LVADs. Minimally invasive procedures improve surgical outcome; for example, they lower the rates of operative complications (such as bleeding or wound infection). The miniaturization of LVADs will continue, so that minimally invasive techniques will be used for most implantations in the future. In this article, we summarize and describe minimally invasive state-of-the-art implantation techniques, with a focus on the most common LVAD systems in adults.

Minimally invasive left ventricular assist device explantation after cardiac recovery: surgical technical considerations.

The new generation of left ventricular assist devices (LVADs) has enabled minimally invasive surgical procedures for implantation. Herein we present two alternative approaches for minimally invasive LVAD explantation following cardiac recovery, avoiding a sternotomy and improving patient safety.

Minimally invasive off-pump left ventricular assist device exchange: anterolateral thoracotomy.

The new generation of left ventricular assist devices has enabled minimally invasive surgical procedures. Herein we present a novel technique of left ventricular assist device exchange through a left-sided anterolateral thoracotomy.

Hemodynamical Evaluation of a New Surgically Implanted Pulsatile Right Ventricular Assist Device Driven by a Conventional Intra-Aortic Balloon Pump Console.

Severe right heart failure, often overlooked and challenging to manage, has prompted a growing interest in innovative approaches to provide functional support. This study uses experimentation in large porcine models to introduce a novel prototype of a pulsatile mechanical circulatory support device and document its effects when deployed as a right ventricular assist device (RVAD). The pulsatile ventricular assist platform (pVAP), featuring a membrane pump driven by an intra-aortic balloon pump console, actively generates pulsatile flow to propel right ventricular blood into the pulmonary artery. This novel prototype demonstrates promising potential in addressing the challenges of right heart failure management. After preliminary in vitro assessments, the pVAP was tested on seven porcine models in a healthy state and after the induction of right ventricular failure. During the procedure, a set of standard (ie, standard-of-care) hemodynamic measurements was obtained. Additionally, invasive pressure-volume loop analysis was employed to examine left ventricular hemodynamics. Results indicated that activation of the pVAP during right ventricular failure significantly improved systemic hemodynamics and enhanced left ventricular function. This study sheds light on the potential of the pVAP in managing right heart failure.

Use of left atrial appendage as an autologous tissue source for epicardial micrograft transplantation during LVAD implantation.

We report here the first clinical use of the left atrial appendage (LAA) for epicardial micrograft transplantation during left ventricular assist device (LVAD) implantation. Previously, a sample from the right atrial appendage (RAA) has been available for processing and administering micrograft therapy in cardiac surgery. Both LAA and RAA are rich sources of various types of myocardial cells and are capable of providing both paracrine and cellular support to the failing myocardium. The surgical approach of LAA micrografting facilitates epicardial micrograft therapy dose escalation and treatment of larger myocardial areas than done previously. Moreover, as collection of treated vs. untreated tissues from the recipient heart is possible following LVAD implantation at the time of heart transplantation, the evaluation of the therapy's mechanism of action can be further deciphered at cellular and molecular levels. This LAA modification of the epicardial micrografting technique has the overall potential to facilitate the adoption of cardiac cell therapy during heart surgery.

Three-month outcomes after the implantation of two HeartMate 3 devices in total artificial heart configuration.

BACKGROUND: Total artificial heart (TAH) implantation is a rarely performed procedure. Contrarily, left ventricular assist device (VAD) implantation is rather common in many centers. As transplantation is quantitatively limited cardiac replacement with artificial hearts is a viable alternative in the treatment of severe biventricular heart failure. An alternative to TAH is the implantation of two VADs in a TAH configuration. We hereby present the first multi-center study on 3-months outcomes of patients treated by cardiectomy and placement of two HeartMate 3s in a TAH configuration. METHODS: We retrospectively investigated a cohort of 15 patients that underwent HM3-TAH-implantation at three international institutions. Follow-up was 3 months after implantation. Baseline, intra- and postoperative parameters as well as survival data and adverse events were collected. RESULTS: A total of 1089 days on HM3-TAH were observed. Thirty-day survival after HM3-TAH implantation was 53% (8/15) and three month survival was 40% (6/15). The longest duration on device was 274 days. Causes of death were multi-organ failure, sepsis, and neurological adverse events. No technical complications were documented. Two patients remained on the device. Four patients (26%) were successfully bridged to transplantation. CONCLUSIONS: The implantation of two HeartMate 3s in a TAH configuration is a last resort and off-label concept in cases of extreme biventricular heart failure. In a diligently selected patient cohort, HM3-TAH implantation is a feasible method to increase the chance of survival in a severely ill patient cohort and successfully bridge patients to heart transplantation that would otherwise have died.