True Aneurysm on Posterior Tibial Artery as Late Complication of SARS-CoV-2.

We describe the story of a 70- year-old Italian male that almost 4 months later respiratory infection by SARS-CoV-2 presented a rapid evolution of a true aneurism of the right posterior tibial artery (PTA).

Oversampling and replacement strategies in propensity score matching: a critical review focused on small sample size in clinical settings.

BACKGROUND: Propensity score matching is a statistical method that is often used to make inferences on the treatment effects in observational studies. In recent years, there has been widespread use of the technique in the cardiothoracic surgery literature to evaluate to potential benefits of new surgical therapies or procedures. However, the small sample size and the strong dependence of the treatment assignment on the baseline covariates that often characterize these studies make such an evaluation challenging from a statistical point of view. In such settings, the use of propensity score matching in combination with oversampling and replacement may provide a solution to these issues by increasing the initial sample size of the study and thus improving the statistical power that is needed to detect the effect of interest. In this study, we review the use of propensity score matching in combination with oversampling and replacement in small sample size settings. METHODS: We performed a series of Monte Carlo simulations to evaluate how the sample size, the proportion of treated, and the assignment mechanism affect the performances of the proposed approaches. We assessed the performances with overall balance, relative bias, root mean squared error and nominal coverage. Moreover, we illustrate the methods using a real case study from the cardiac surgery literature. RESULTS: Matching without replacement produced estimates with lower bias and better nominal coverage than matching with replacement when 1:1 matching was considered. In contrast to that, matching with replacement showed better balance, relative bias, and root mean squared error than matching without replacement for increasing levels of oversampling. The best nominal coverage was obtained by using the estimator that accounts for uncertainty in the matching procedure on sets of units obtained after matching with replacement. CONCLUSIONS: The use of replacement provides the most reliable treatment effect estimates and that no more than 1 or 2 units from the control group should be matched to each treated observation. Moreover, the variance estimator that accounts for the uncertainty in the matching procedure should be used to estimate the treatment effect.

Biventricular assistance with 2 hm3 in a small chest patient: extra-pericardial implant.

We describe the clinical course and treatment of a 53-year-old female, with small chest dimensions, referred to our institution for a primary cardiogenic shock. The patient underwent an on-pump left ventricular assist-device (VAD) implantation with the aid of immediate post-operative paracorporeal right-VAD assistance for an acute right ventricular failure. After two unsuccessful weaning attempts, she underwent extrapericardial HM 3 RVAD implantation.

How to evaluate the outflow tract of LVAD after minimally invasive implantation by 3D CT-scan.

During a minimally invasive implantation technique, the outflow graft of left ventricular assist device (LVAD) is tunnelled blindly through the pericardium or left pleura, with an inability to assess for twisting or malposition. Three-dimensional computed tomography scan (CT-scan) has a role in qualitative evaluation of the different outflow tract configurations. The different surgical minimally invasive approaches include: (a) mini-sternotomy and left mini-thoracotomy, (b) right mini-thoracotomy and left mini-thoracotomy, (c) subclavian artery access and left mini-thoracotomy. The outflow graft could be anastomosed to the left axillary artery or the ascending aorta. CT-scan reconstruction using syngo InSpace4D (Siemens, Muenchen, Germany) was used to provide fast segmentation and high-resolution images. The 3D reconstructions permit an evaluation of different anastomosis configurations and to assess the route of outflow graft.

Bilateral mini-thoracotomy approach for minimally invasive implantation of HeartMate 3.

Left ventricular assist devices (LVADs) are an established option for the treatment of end-stage heart failure. Last-generation devices are characterized by a miniaturized pump size, allowing for intra-pericardial placement. This feature enabled the introduction of less-invasive implantation techniques, which have been linked to many favorable effects. The HeartMate 3 LVAD is a continuous-flow centrifugal pump, recently introduced for clinical use. Here, we describe the minimally invasive implantation of the HeartMate 3 through a bilateral mini-thoracotomy.

Minimally Invasive Implantation of Continuous Flow Left Ventricular Assist Devices: The Evolution of Surgical Techniques in a Single-Center Experience.

In this work we aimed to evaluate the evolution of our surgical experience with the implantation of a continuous flow left ventricular assist device (LVAD), from the original full sternotomy approach to less invasive surgical strategies including mini-sternotomy and/or mini-thoracotomies. We reviewed all consecutive patients implanted with a continuous flow LVAD at our Institute. To exclude the possible bias related to the device used, out of 91 collected LVADs implants, we selected only those patients (n = 42) who received, between 2012 and 2015, the HeartWare HVAD. The analysis focused on the surgical approach used for the LVAD implant. Most of the patients (95%) were affected by dilated or ischemic cardiomyopathy, with an INTERMACS class I-II in the majority of cases (77%). The LVAD implant was performed through a full sternotomy in 10 patients (24%); the remaining 32 cases (76%) were managed with minimally invasive procedures. These were left mini-thoracotomy with upper mini-sternotomy (20 patients, 62%), right and left mini-thoracotomy (7 patients, 22%), and a recently developed left mini-thoracotomy with outflow graft anastomosis to the left axillary artery (5 patients, 16%). The most common adverse event on device was right heart failure (26%). Eighteen patients (43%) were transplanted. Overall estimated 24 months survival (on device or after transplant) was 68 ± 7%. The causal analysis, adjusted by propensity score weighting baseline data and sample size, showed that left mini-thoracotomy with outflow anastomosis to the left axillary artery resulted in a significantly reduced rate of post implant right heart failure (P < 0.01), and mechanical ventilation time (P = 0.049). To conclude, in our series, by applying mini-invasive implant techniques in the majority of cases, mid-term survival of continuous flow LVADs in severely compromised patients was satisfactory. In the adjusted analysis, the left anterior mini-thoracotomy with outflow anastomosis to the left axillary artery showed the most favorable results.

How to implant the Jarvik 2000 post-auricular driveline: evolution to a novel technique.

The post-auricular (PA) driveline positioning for percutaneous power delivery is a specific feature of the Jarvik 2000 FlowMaker LVAD. We applied several technical refinements to optimise the PA implant. Here, we present and discuss these modifications. We retrospectively reviewed all patients implanted with Jarvik 2000 at our Institution. Different PA implant techniques were described. A machine learning analysis was performed to evaluate the determinants of driveline infection. From December 2008 to December 2017, 62 patients were implanted with Jarvik 2000, at our Institution. The PA connection was managed through the "question mark-shaped" incision in 24 patients (39%) and with the "C-shaped" in 18 (29%), whereas 10 (16%) cases received the "vertical incision" and 10 (16%) the "orthogonal incision". The implant technique resulted highly predictive of driveline infection. The rate of driveline infections was numerically lower among cases managed with the last two techniques. After evolving through different implant techniques, we propose and suggest the "orthogonal incision" to maximise the advantages of the Jarvik 2000 post-auricular driveline.

Left ventricle assist devices and driveline's infection incidence: a single-centre experience.

Different left ventricular assist devices (LVADs) are provided of different driveline exit sites: HeartWare HVAD presents abdominal power-cable-supply, while the Jarvik 2000 LVAD is powered by a retroauricular driveline. We analyzed 93 LVAD-implanted patients from January-2009 to October-2016 (41 HeartWare and 52 Jarvik 2000), hypothesizing a different incidence of infection, according to driveline exit site. The two populations were propensity matched for the demographic data and preoperative variables, and the outcomes were further analyzed. Nine driveline infections (DLIs) were in each LVAD group recorded (22% for HVAD and 17% for Jarvik 2000). The incidence of the complication was similar between groups (p = 0.97), even during time (p = 0.27 within 6 months and p = 0.16 over 6 months of support). Age at implant (p = 0.01), revision for bleeding (p = 0.05), days of postoperative intubation (p = 0.002), and ICU stay (p < 0.001), as well as days on device (p < 0.001) were identified as risk factors for DLIs. The type of device and the driveline exit site were not statistically co-related to infections. Similar infection-freedom survival was identified (p = 0.87). Younger age at implant, revision for bleeding, prolonged mechanical ventilation, delayed rehabilitation, as well as long time LVAD support were identified as risk factors for exit site DLIs. Despite similar incidence of DLIs, the different management and care of the retroauricular exit site makes it more appropriate and comfortable in long-term support.

The danger of using a sledgehammer to crack a nut: ROTEM-guided administration of recombinant activated factor VII in a patient with refractory bleeding post-ventricular assist device implantation.

Recombinant activated factor VII (rFVIIa) is currently approved for treating or preventing hemorrhage in patients with hemophilia, Glanzmann's thrombasthenia, or congenital FVII deficiency. Its "off-label" use for massive bleeding in the setting of trauma or surgery has been increasing because of demonstrated efficacy. However, the use of rFVIIa also carries a high thrombo-embolic risk. This is particularly true in cardiac surgery patients, especially those treated with mechanical circulatory support. We describe the case of a patient treated with a biventricular assist device in our center, in whom severe bleeding was treated in a targeted manner, using rotational thromboelastometry to guide administration and dosing of rFVIIa. A comprehensive review of the emerging literature on the use of rFVIIa postventricular assist device implantation accompanies the case to highlight the need for careful selection of prohemostatic agents in this high-risk group.

Less-invasive off-pump ventricular assist device implantation in regional paravertebral analgesia.

We describe the clinical course and treatment of a 58-year-old male with a primary cardiogenic shock, who underwent a minimally invasive off-pump ventricular-assist-device (VAD) implantation with the aid of paravertebral regional analgesia. He was extubated soon after the procedure, in the operating room, with the aim to reduce the right ventricle impairment. We illustrate how a minimally invasive implant may improve the clinical outcomes of VAD patients shortening their return time to active life.

Marginal versus Standard Donors in Heart Transplantation: Proper Selection Means Heart Transplant Benefit.

BACKGROUND: In this study, we assessed the mid-term outcomes of patients who received a heart donation from a marginal donor (MD), and compared them with those who received an organ from a standard donor (SD). METHODS: All patients who underwent HTx between January 2012 and December 2020 were enrolled at a single institution. The primary endpoints were early and long-term survival of MD recipients. Risk factors for primary graft failure (PGF) and mortality in MD recipients were also analyzed. The secondary endpoint was the comparison of survival of MD versus SD recipients. RESULTS: In total, 238 patients underwent HTx, 64 (26.9%) of whom received an organ from an MD. Hospital mortality in the MD recipient cohort was 23%, with an estimated 1 and 5-year survival of 70% (59.2-82.7) and 68.1% (57.1-81), respectively. A multivariate analysis in MD recipients showed that decreased renal function and increased inotropic support of recipients were associated with higher mortality (p = 0.04 and p = 0.03). Cold ischemic time (p = 0.03) and increased donor inotropic support (p = 0.04) were independent risk factors for PGF. Overall survival was higher in SD than MD (85% vs. 68% at 5 years, log-rank = 0.008). However, risk-adjusted mortality (p = 0.2) and 5-year conditional survival (log-rank = 0.6) were comparable. CONCLUSIONS: Selected MDs are a valuable resource for expanding the cardiac donor pool, showing promising results. The use of MDs after prolonged ischemic times, increased inotropic support of the MD or the recipient and decreased renal function are associated with worse outcomes.

A Device Strategy-Matched Comparison Analysis among Different Intermacs Profiles: A Single Center Experience.

Background: The present study evaluates outcomes of LVAD patients, taking into account the device strategy and the INTERMACS profile. Methods: We included 192 LVAD-patients implanted between January 2012 and May 2021. The primary and secondary end-points were survival and major adverse events between Profiles 1-3 vs. Profile 4, depending on implantation strategies (Bridge-to-transplant-BTT; Bridge-to-candidacy-BTC; Destination-Therapy-DT). Results: The overall survival was 67% (61-75) at 12 months and 61% (54-70) at 24 months. Profile 4 patients showed significantly higher survival (p = 0.018). Incidences of acute right-ventricular-failure (RVF) (p = 0.046), right-ventricular-assist-device (RVAD) implantation (p = 0.015), and continuous-venovenous-hemofiltration (CVVH) (p = 0.006) were higher in Profile 1-3 patients, as well as a longer intensive care unit stays (p = 0.050) and in-hospital-mortality (p = 0.012). Twelve-month and 24-month survival rates were higher in the BTT rather than in BTC (log-rank = 0.410; log-rank = 0.120) and in DT groups (log-rank = 0.046). In the BTT group, Profile 1-3 patients had a higher need for RVAD support (p = 0.042). Conclusions: LVAD implantation in elective patients was associated with better survival and lower complications incidence. LVAD implantation in BTC patients has to be considered before their conditions deteriorate. DT should be addressed to elective patients in order to guarantee acceptable results.

Impact of Continuous Flow Left Ventricular Assist Device on Heart Transplant Candidates: A Multi-State Survival Analysis.

(1) Objectives: The aim of this study was to investigate the impact of the prolonged use of continuous-flow left ventricular assist devices (LVADs) on heart transplant (HTx) candidates. (2) Methods: Between January 2012 and December 2019, we included all consecutive patients diagnosed with end-stage heart failure considered for HTx at our institution, who were also eligible for LVAD therapy as a bridge to transplant (BTT). Patients were divided into two groups: those who received an LVAD as BTT (LVAD group) and those who were listed without durable support (No-LVAD group). (3) Results: A total of 250 patients were analyzed. Of these, 70 patients (28%) were directly implanted with an LVAD as BTT, 11 (4.4%) received delayed LVAD implantation, and 169 (67%) were never assisted with an implantable device. The mean follow-up time was 36 ± 29 months. In the multivariate analysis of survival before HTx, LVAD implantation showed a protective effect: LVAD vs. No-LVAD HR 0.01 (p < 0.01) and LVAD vs. LVAD delayed HR 0.13 (p = 0.02). Mortality and adverse events after HTx were similar between LVAD and No-LVAD (p = 0.65 and p = 0.39, respectively). The multi-state survival analysis showed a significantly higher probability of death for No-LVAD vs. LVAD patients with (p = 0.03) or without (p = 0.04) HTx. (4) Conclusions: The use of LVAD as a bridge to transplant was associated with an overall survival benefit, compared to patients listed without LVAD support.

Morphologic investigation on Perceval S, a sutureless pericardial valve prosthesis: collagen integrity after collapsing-ballooning and structural valve deterioration at distance.

Perceval S is a self-expandable, stent-mounted bioprosthetic valve (BPV), with glutaraldehyde treated bovine pericardium, processed with homocysteic acid as an anti-calcification treatment. The stent is crimpable but the valve insertion is done surgically via a shorter procedure which does not require sutures. OBJECTIVES: MATERIAL AND METHODS: RESULTS: CONCLUSIONS: Collapsing and ballooning do not alter cusp collagen periodicity. Structural valve deterioration with stenosis, due to dystrophic calcification and fibrous tissue overgrowth, seldom occurred in the mid-term. Glutaraldehyde fixed pericardium has the potential to undergo structural valve deterioration with time, similar to well-known BPV failure. This supports the recommendation to pursue improvement of tissue valve treatment with enhanced durability.

Outcomes of patients with continuous flow left ventricular assist device undergoing emergency endovascular treatment for atraumatic bleeding.

INTRODUCTION: Severe spontaneous bleeding is a significant complication in patients with continuous flow left ventricular assist devices; there is little evidence on endovascular treatment to support its use. MATERIALS AND METHODS: We observed seven patients (five men, two women, age 43-67 years) with continuous flow left ventricular assist devices on antiaggregant/coagulant therapy, admitted to our hospital for uncorrectable symptomatic anemia; CT-angiography and diagnostic angiography confirmed the presence of atraumatic arterious bleeding from the gastrointestinal tract (six patients), from the intercostal artery and from the bronchial tree (one patient). RESULTS: All patients where successfully treated via an endovascular approach with superselective embolization of the involved arterial branches with coils and particles. CONCLUSION: Spontaneous atraumatic bleeding is a frequent complication in patients with continuous flow left ventricular assist devices; endovascular treatment represents a promising alternative to the surgical approach as it is less invasive, easily repeatable and associated to a reduced procedural risk.

Results of new-generation intrapericardial continuous flow left ventricular assist devices as a bridge-to-transplant.

AIMS: We analysed the outcomes with the use of a new-generation continuous-flow left ventricular assist device (CF-LVAD) as a bridge-to-transplant (BTT). MATERIALS AND METHODS: We included all patients implanted with an intrapericardial CF-LVAD as BTT, between January 2012 and December 2016. Primary outcomes were overall survival, survival on waiting list and postheart transplant (HTx) survival. The outcomes after HTx were compared with those of a contemporary cohort of patients transplanted without previous CF-LVAD (No-LVAD group, n = 73). RESULTS: We included 53 patients with a median age of 52 years (interquartile range: 43-59 years). Seventy-two percent were in INTERMACS profile 1-2 before implant; all entered the HTx waiting list after receiving the CF-LVAD. HTx was performed in 42 (79%) cases (LVAD group). Overall estimated survival (considering both pre-HTx and post-HTx) was 89% [95% confidence interval (CI) 81-98%] at 1 year and 80% (CI 70-92%) at 2 years. The estimated survival on waiting list was 91% (CI 80-100%) at 6 months, whereas the 1-year estimated post-HTx survival was 88% (CI 79-98%). The Kaplan-Meier curves of survival after HTx of LVAD versus No-LVAD group were comparable (log-rank P = 0.54), as well as the rates of post-HTx adverse events. A multivariable model of survival after HTx, accounting for the most relevant patient characteristics, identified LVAD use as a significant protective factor [LVAD versus No-LVAD hazard ratio 0.22 (CI 0.06-0.91)]. CONCLUSION: The use of new-generation intrapericardial CF-LVADs as a BTT resulted, in our series, in satisfactory pre-HTx and post-HTx outcomes.

Comprehensive effects of left ventricular assist device speed changes on alveolar gas exchange, sleep ventilatory pattern, and exercise performance.

BACKGROUND: Increasing left ventricular assist device (LVAD) pump speed according to the patient's activity is a fascinating hypothesis. This study analyzed the short-term effects of LVAD speed increase on cardiopulmonary exercise test (CPET) performance, muscle oxygenation (near-infrared spectroscopy), diffusion capacity of the lung for carbon monoxide (Dlco) and nitric oxide (Dlno), and sleep quality. METHODS: We analyzed CPET, Dlco and Dlno, and sleep in 33 patients supported with the Jarvik 2000 (Jarvik Heart Inc., New York, NY). After a maximal CPET (n = 28), patients underwent 2 maximal CPETs with LVAD speed randomly set at 3 or increased from 3 to 5 during effort (n = 15). Then, at LVAD speed randomly set at 2 or 4, we performed (1) constant workload CPETs assessing O2 kinetics, cardiac output (CO), and muscle oxygenation (n = 15); (2) resting Dlco and Dlno (n = 18); and (3) nocturnal cardiorespiratory monitoring (n = 29). RESULTS: The progressive pump speed increase raised peak volume of oxygen consumption (12.5 ± 2.5 ml/min/kg vs 11.7 ± 2.8 ml/min/kg at speed 3; p = 0.001). During constant workload, from speed 2 to 4, CO increased (at rest: 3.18 ± 0.76 liters/min vs 3.69 ± 0.75 liters/min, p = 0.015; during exercise: 5.91 ± 1.31 liters/min vs 6.69 ± 0.99 liters/min, p = 0.014), and system efficiency (τ = 65.8 ± 15.1 seconds vs 49.9 ± 14.8 seconds, p = 0.002) and muscle oxygenation improved. At speed 4, Dlco decreased, and obstructive apneas increased despite a significant apnea/hypopnea index and a reduction of central apneas. CONCLUSIONS: Short-term LVAD speed increase improves exercise performance, CO, O2 kinetics, and muscle oxygenation. However, it deteriorates lung diffusion and increases obstructive apneas, likely due to an increase of intrathoracic fluids. Self-adjusting LVAD speed is a fascinating but possibly unsafe option, probably requiring a monitoring of intrathoracic fluids.

A pilot study on the efficacy and safety of a minimally invasive surgical and anesthetic approach for ventricular assist device implantation.

BACKGROUND: The aim of our study was to compare 2 surgical and anesthetic approaches during ventricular assist device implantation. METHODS: 68 patients (50.4 ± 17.1 years old) were supported with the HeartWare® HVAD (32 patients) and the Jarvik 2000 VAD (36 patients) between January 2010 and August 2016. Two surgical techniques were applied: a minimally invasive approach with the aid of paravertebral-block (mini-invasive group, 41 patients) and a standard-surgical-approach with the aid of general anesthesia (27 patients). RESULTS: The minimally invasive approach allowed faster postoperative recovery by significantly reducing the duration of surgery (p<0.05), anesthesia (p<0.05), mechanical ventilation (p<0.05), inotropic support (p<0.05), ICU and in-hospital stay (p<0.05), and time to first mobilization (p<0.05). No case of epidural hematoma was observed. Eleven patients died (16%) at 30 days, 3 in the mini-invasive group (7.3%) and 8 in the invasive group (29.6%). CONCLUSIONS: Minimally invasive approaches play a substantial role in VAD surgery by facilitating faster recovery, which is important for patients at very high risk.