Repeat left ventricular-assisted device exchange and upgrade from second- to third-generation devices in a high-volume single center

BACKGROUND

Pump exchange is an established strategy to treat LVAD-related complications such as thrombosis, infection, and driveline failure. Pump upgrades with an exchange to newer generation devices are being performed to the advantage of the patient on long-term support. The safety and efficacy of a repeat LVAD exchange with a concomitant upgrade to a third-generation pump have not been reported.

METHODS

We performed a retrospective analysis of all consecutive patients who underwent a repeat LVAD device exchange and upgrade to HeartMate III (HMIII) at Houston Methodist Hospital between December 2018 and December 2020.

RESULTS

Five patients underwent exchange and upgrade to HMIII within the specified timeframe. Four patients had already had two prior exchanges (all HMII to HMII), and one patient had one prior exchange (HVAD to HVAD). In all cases, implantation was performed as destination therapy. The surgical exchange was performed via redo median sternotomy on full cardiopulmonary bypass. No unplanned redo surgery of the device component was required. In-hospital mortality was 20% in this very high-risk population. At 1-, 3-, and 6-month follow-up, all discharged patients were on HMIII support, with no major LVAD-related adverse events reported.

CONCLUSION

We report the feasibility and safety of a repeat pump exchange with an upgrade to HMIII in a high-volume center. The decision for medical therapy versus surgical exchange has to be tailored to individual cases based on risk factors and clinical stability but in expert hands, even a re-redo surgical approach grants options for good medium-term outcomes.

Progress in Combined Liver-lung Transplantation at a Single Center

Combined liver-lung transplantation is an uncommon, although vital, procedure for patients with simultaneous end-stage lung and liver disease. The utility of lung-liver transplant has been questioned because of initial poor survival outcomes, particularly when compared with liver-alone transplant recipients.

Methods

A single-center, retrospective review of the medical records of 19 adult lung-liver transplant recipients was conducted, comparing early recipients (2009-2014) with a recent cohort (2015-2021). Patients were also compared with the center's single lung or liver transplant recipients.

Results

Recent lung-liver recipients were older (P = 0.004), had a higher body mass index (P = 0.03), and were less likely to have ascites (P = 0.02), reflecting changes in the etiologies of lung and liver disease. Liver cold ischemia time was longer in the modern cohort (P = 0.004), and patients had a longer posttransplant length of hospitalization (P = 0.048). Overall survival was not statistically different between the 2 eras studied (P = 0.61), although 1-y survival was higher in the more recent group (90.9% versus 62.5%). Overall survival after lung-liver transplant was equivalent to lung-alone recipients and was significantly lower than liver-alone recipients (5-y survival: 52%, 51%, and 75%, respectively). Lung-liver recipient mortality was primarily driven by deaths within 6 mo of transplant due to infection and sepsis. Graft failure was not significantly different (liver: P = 0.06; lung: P = 0.74).

Conclusions

The severity of illness in lung-liver recipients combined with the infrequency of the procedure supports its continued use. However, particular attention should be paid to patient selection, immunosuppression, and prophylaxis against infection to ensure proper utilization of scarce donor organs.

Outflow cannula alignment in continuous flow left ventricular devices is associated with stroke

We sought to evaluate whether differences in left ventricular assist device (LVAD) canula alignment are associated with stroke. There is a paucity of clinical data on contribution of LVAD canulae alignment to strokes. We conducted a retrospective analysis of patients who underwent LVAD implantation at Houston Methodist hospital from 2011 to 2016 and included those who had undergone cardiac computed tomography (CT) with contrast. LVAD graft alignment using X-ray, echocardiography, and cardiac CT was evaluated. The primary outcome was stroke within 1 year of LVAD implantation. Of the 101 patients that underwent LVAD Implantation and cardiac CT scan during the study period, 78 met inclusion criteria. The primary outcome occurred in 12 (15.4%) patients with a median time to stroke of 77 days (interquartile range: 42-132 days). Of these, 10 patients had an ischemic and two had hemorrhagic strokes. The predominant device type was Heart Mate II (94.8%). Patients with LVAD outflow cannula to aortic angle lesser than 37.5° and those with outflow graft diameter of anastomosis less than 1.5 cm (assessed by cardiac CT) had significantly higher stroke risk (p < 0.001 and p = 0.01 respectively). In HMII patients, a lower LVAD speed at the time of CT scan was associated with stroke. Further studies are needed to identify optimal outflow graft configuration to mitigate stroke risk.

Extracorporeal Membrane Oxygenation for COVID-19: Collaborative Experience From the Texas Medical Center in Houston With 2 Years Follow-Up

Patients with severe refractory hypoxemic respiratory failure may benefit from extracorporeal membrane oxygenation (ECMO) for salvage therapy. The Coronavirus disease 2019 (COVID-19) pandemic offered three high-volume independent ECMO programs at a large medical center the chance to collaborate to optimize ECMO care at the beginning of the pandemic in Spring 2020. Between March 15, 2020, and May 30, 2020, 3,615 inpatients with COVID-19 were treated at the Texas Medical Center. During this time, 35 COVID-19 patients were cannulated for ECMO, all but one in a veno-venous configuration. At hospital discharge, 23 (66%) of the 35 patients were alive. Twelve patients died of vasodilatory shock (n = 9), intracranial hemorrhage (n = 2), and cannulation-related bleeding and multiorgan dysfunction (n = 1). The average duration of ECMO was 13.6 days in survivors and 25.0 days in nonsurvivors ( p < 0.04). At 1 year follow-up, all 23 discharged patients were still alive, making the 1 year survival rate 66% (23/35). At 2 years follow-up, the overall rate of survival was 63% (22/35). Of those patients who survived 2 years, all were at home and alive and well at follow-up.

A multi-institutional retrospective analysis on impact of RV acute mechanical support timing after LVAD implantation on 1-year mortality and predictors of RV acute mechanical support weaning

BACKGROUND

There is little insight into which patients can be weaned off right ventricular (RV) acute mechanical circulatory support (AMCS) after left ventricular assist device (LVAD) implantation. We hypothesize that concomitant RV AMCS insertion instead of postoperative implantation will improve 1-year survival and increase the likelihood of RV AMCS weaning.

METHODS

A multicenter retrospective database of 826 consecutive patients who received a HeartMate II or HVAD between January 2007 and December 2016 was analyzed. We identified 91 patients who had early RV AMCS on index admission. Cox proportional-hazards model was constructed to identify predictors of 1-year mortality post-RV AMCS implantation and competing risk modeling identified RV AMCS weaning predictors.

RESULTS

There were 91 of 826 patients (11%) who required RV AMCS after CF-LVAD implantation with 51 (56%) receiving a concomitant RV AMCS and 40 (44%) implanted with a postoperative RV AMCS during their ICU stay; 48 (53%) patients were weaned from RV AMCS support. Concomitant RV AMCS with CF-LVAD insertion was associated with lower mortality (HR 0.45 [95% CI 0.26-0.80], p = 0.01) in multivariable model (which included age, BMI, angiotensin-converting enzyme inhibitor use, and heart transplantation as a time-varying covariate). In the multivariate competing risk analysis, a TPG < 12 (SHR 2.19 [95% CI 1.02-4.70], p = 0.04) and concomitant RV AMCS insertion (SHR 3.35 [95% CI 1.73-6.48], p < 0.001) were associated with a successful wean.

CONCLUSIONS

In patients with RVF after LVAD implantation, concomitant RV AMCS insertion at the time of LVAD was associated with improved 1-year survival and increased chances of RV support weaning compared to postoperative insertion.

Predicting post-operative right ventricular failure using video-based deep learning

Despite progressive improvements over the decades, the rich temporally resolved data in an echocardiogram remain underutilized. Human assessments reduce the complex patterns of cardiac wall motion, to a small list of measurements of heart function. All modern echocardiography artificial intelligence (AI) systems are similarly limited by design - automating measurements of the same reductionist metrics rather than utilizing the embedded wealth of data. This underutilization is most evident where clinical decision making is guided by subjective assessments of disease acuity. Predicting the likelihood of developing post-operative right ventricular failure (RV failure) in the setting of mechanical circulatory support is one such example. Here we describe a video AI system trained to predict post-operative RV failure using the full spatiotemporal density of information in pre-operative echocardiography. We achieve an AUC of 0.729, and show that this ML system significantly outperforms a team of human experts at the same task on independent evaluation.

Long-term survival in patients with post-LVAD right ventricular failure: multi-state modelling with competing outcomes of heart transplant

BACKGROUND

Multicenter data on long term survival following LVAD implantation that make use of contemporary definitions of RV failure are limited. Furthermore, traditional survival analyses censor patients who receive a bridge to heart transplant. Here we compare the outcomes of LVAD patients who develop post-operative RV failure accounting for the transitional probability of receiving an interim heart transplantation.

METHODS

We use a retrospective cohort of LVAD patients sourced from multiple high-volume centers based in the United States. Five- and ten-year survival accounting for transition probabilities of receiving a heart transplant were calculated using a multi-state Aalen Johansen survival model.

RESULTS

Of the 897 patients included in the study, 238 (26.5%) developed post-operative RV failure at index hospitalization. At 10 years the probability of death with post-op RV failure was 79.28% vs 61.70% in patients without (HR 2.10; 95% CI 1.72 - 2.57; p = < .001). Though not significant, patients with RV failure were less likely to be bridged to a heart transplant (HR 0.87, p = .4). Once transplanted the risk of death between both patient groups remained equivalent; the probability of death after a heart transplant was 3.97% in those with post-operative RV failure shortly after index LVAD implant, as compared to 14.71% in those without.

CONCLUSIONS AND RELEVANCE

Long-term durable mechanical circulatory support is associated with significantly higher mortality in patients who develop post-operative RV failure. Improving outcomes may necessitate expeditious bridge to heart transplant wherever appropriate, along with critical reassessment of organ allocation policies.

Ventricular Fibrillation Arrest and Pulmonary Homograft Rupture During Transcatheter Pulmonary Valve: Successful Rescue by Heart Team

We describe a 31-year-old woman with pulmonary homograft rupture and ventricular fibrillation arrest complicating a transcatheter pulmonary valve (TPV) procedure. She underwent extracorporeal membrane oxygenation (ECMO) with immediate surgical repair including bioprosthetic pulmonary valve replacement. She had difficulty weaning off ECMO due to hyperacute failure of the valve and ultimately underwent successful hybrid TPV with complete recovery. This case illustrates the importance of the heart team approach during catheter and surgical interventions in adult congenital heart disease.

Prediction of right heart failure after left ventricular assist implantation: external validation of the EUROMACS right-sided heart failure risk score

AIMS

Prediction of right heart failure (RHF) after left ventricular assist device (LVAD) implant remains a challenge. The EUROMACS right-sided heart failure (EUROMACS-RHF) risk score was proposed as a prediction tool for post-LVAD RHF but lacks from large external validation. The aim of our study was to externally validate the score.

METHODS AND RESULTS

From January 2007 to December 2017, 878 continuous-flow LVADs were implanted at three tertiary centres. We calculated the EUROMACS-RHF score in 662 patients with complete data. We evaluated its predictive performance for early RHF defined as either (i) need for short- or long-term right-sided circulatory support, (ii) continuous inotropic support for ≥14 days, or (iii) nitric oxide for ≥48 h post-operatively. Right heart failure occurred in 211 patients (32%). When compared with non-RHF patients, pre-operatively they had higher creatinine, bilirubin, right atrial pressure, and lower INTERMACS class (P < 0.05); length of stay and in-hospital mortality were higher. Area under the ROC curve for RHF prediction of the EUROMACS-RHF score was 0.64 [95% confidence interval (CI) 0.60-0.68]. Reclassification of patients with RHF was significantly better when applying the EUROMACS-RHF risk score on top of previous published scores. Patients in the high-risk category had significantly higher in-hospital and 2-year mortality [hazard ratio: 1.64 (95% CI 1.16-2.32) P = 0.005].

CONCLUSION

In an external cohort, the EUROMACS-RHF had limited discrimination predicting RHF. The clinical utility of this score remains to be determined.

Successful Treatment of Pregnant and Postpartum Women With Severe COVID-19 Associated Acute Respiratory Distress Syndrome With Extracorporeal Membrane Oxygenation

There are limited data on the use of extracorporeal membrane oxygenation (ECMO) for pregnant and peripartum women with COVID-19 associated acute respiratory distress syndrome (ARDS). Pregnant women may exhibit more severe infections with COVID-19, requiring intensive care. We supported nine pregnant or peripartum women with COVID-19 ARDS with ECMO, all surviving and suffering no major complications from ECMO. Our case series demonstrates high-maternal survival rates with ECMO support in the management of COVID-19 associated severe ARDS, highlighting that these pregnant and postpartum patients should be supported with ECMO during this pandemic.

Association of Clinical Outcomes With Left Ventricular Assist Device Use by Bridge to Transplant or Destination Therapy Intent: The Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) Randomized Clinical Trial

Question

In patients with advanced heart failure, do outcomes with left ventricular assist device implantation differ by the initial intended goal of therapy as a bridge to transplant or destination therapy?

Findings

In this randomized clinical trial, the composite end point of survival free of disabling stroke or reoperation to remove or replace a malfunctioning device at 2 years was significantly better with the magnetically levitated centrifugal-flow HeartMate 3 than the mechanical-bearing axial-flow HeartMate II, irrespective of preimplant therapeutic intent. Event-free survival was not different between patients in the bridge to transplant or destination therapy groups treated with the HeartMate 3 pump.

Meaning

Per this randomized clinical trial, use of categorizations based on current or future transplant eligibility should be abandoned in favor of a single treatment indication for use of left ventricular assist devices.

Importance

Left ventricular assist devices (LVADs) are well established in the treatment of advanced heart failure, but it is unclear whether outcomes are different based on the intended goal of therapy in patients who are eligible vs ineligible for heart transplant.

Objective

To determine whether clinical outcomes in the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) trial differed by preoperative categories of bridge to transplant (BTT) or bridge to transplant candidacy (BTC) vs destination therapy (DT).

Design, Setting, and Participants

This study was a prespecified secondary analysis of the MOMENTUM 3 trial, a multicenter randomized clinical trial comparing the magnetically levitated centrifugal-flow HeartMate 3 (HM3) LVAD to the axial-flow HeartMate II (HMII) pump. It was conducted in 69 centers with expertise in managing patients with advanced heart failure in the United States. Patients with advanced heart failure were randomized to an LVAD, irrespective of the intended goal of therapy (BTT/BTC or DT).

Main Outcomes and Measures

The primary end point was survival free of disabling stroke or reoperation to remove or replace a malfunctioning device at 2 years. Secondary end points included adverse events, functional status, and quality of life.

Results

Of the 1020 patients with implants (515 with HM3 devices [50.5%] and 505 with HMII devices [49.5%]), 396 (38.8%) were in the BTT/BTC group (mean [SD] age, 55 [12] years; 310 men [78.3%]) and 624 (61.2%) in the DT group (mean [SD] age, 63 [12] years; 513 men [82.2%]). Of the patients initially deemed as transplant ineligible, 84 of 624 patients (13.5%) underwent heart transplant within 2 years of LVAD implant. In the primary end point analysis, HM3 use was superior to HMII use in patients in the BTT/BTC group (76.8% vs 67.3% for survival free of disabling stroke and reoperation; hazard ratio, 0.62 [95% CI, 0.40-0.94]; log-rank P = .02) and patients in the DT group (73.2% vs 58.7%; hazard ratio, 0.61 [95% CI, 0.46-0.81]; log-rank P < .001). For patients in both BTT/BTC and DT groups, there were not significantly different reductions in rates of pump thrombosis, stroke, and gastrointestinal bleeding with HM3 use relative to HMII use. Improvements in quality of life and functional capacity for either pump were not significantly different regardless of preimplant strategy.

Conclusions and Relevance

In this trial, the superior treatment effect of HM3 over HMII was similar for patients in the BTT/BTC or DT groups. It is possible that use of arbitrary categorizations based on current or future transplant eligibility should be clinically abandoned in favor of a single preimplant strategy: to extend the survival and improve the quality of life of patients with medically refractory heart failure.

Trial Registration

ClinicalTrials.gov identifier: NCT02224755

Cardiogenic Shock in Perioperative and Intraoperative Settings: A Team Approach

Cardiogenic shock (CS) is a multifactorial disease process with high morbidity and mortality. When it occurs in a peri- or intraoperative setting, factors such as surgery, anesthesia, and post-surgical physiology can negatively affect patient outcomes. Since patient needs often escalate during CS-from medications to mechanical support to palliative care-this disease demands a multidisciplinary approach that encompasses all aspects of medical delivery. Preliminary studies have indicated that a multidisciplinary team approach to CS results in earlier diagnosis and treatment and improves patient outcomes. Here we discuss various management strategies for CS from an anesthesiology, surgery, and critical care perspective.

Pulse assessment is important with blood pressure measurement in individuals with continuous flow left ventricular assist devices

While Doppler and cuff blood pressure techniques are prevalent methods of assessing blood pressure in patients with continuous flow left ventricular assist devices, the impact of pulsatility on measurement is not well established. Retrospective chart analysis of clinical variables including pulse perception, blood pressure (Doppler and standard cuff), and aortic valve opening on echo at clinic visit were abstracted. Stable outpatients on continuous flow left ventricular assist devices support with concomitant portable echo assessment were included. Mean average difference was calculated and Pearson's correlation performed for all those patients who had both Doppler and cuff pressure obtained. In all, 74 Heartmate-II patients with a median time from implant of 380 days were analyzed. A pulse was perceived in 82% of patients with persistent aortic valve opening on portable echo and also in 30% of those who had a persistently closed aortic valve. The mean average difference between the Doppler and systolic cuff pressure was ~13 mmHg (r = 0.5, p = 0.004) when a pulse was present and ~11 mmHg when aortic valve was open (r = 0.68, p < 0.0001). Pulse presence seems to reflect aortic valve opening a majority of the time but not always. In the presence of a prominent pulse or persistent aortic valve opening, the Doppler pressure seems to be more reflective of a systolic pressure than mean perfusion pressure. Hence, assessment of pulsatility needs to be incorporated into blood pressure measurement methods for patients with continuous flow left ventricular assist devices.

Delayed autologous stem cell transplantation following cardiac transplantation experience in patients with cardiac amyloidosis

This study sought to retrospectively investigate the outcomes of patients with light-chain amyloidosis (AL) with advanced cardiac involvement who were treated with a strategy of heart transplantation (HT) followed by delayed autologous stem cell transplantation (ASCT) at 1-year posttransplant. Patients with AL amyloidosis with substantial cardiac involvement have traditionally had very poor survival (eg, several months). A few select centers have reported their outcomes for HT followed by a strategy of early ASCT (ie, 6 months) for CA. The outcomes of patients undergoing a delayed strategy have not been reported. All patients with AL amyloidosis at a single institution undergoing evaluation for HT from 2004-2018 were included. Retrospective analyses were performed. Sixteen patients underwent HT (including two combined heart-kidney transplant) for AL amyloidosis. ASCT was performed in a total of nine patients to date at a median 13.5 months (12.8-32.9 months) post-HT. Survival was 87.5% at 1 year and 76.6% at 5 years, comparable to institutional outcomes for nonamyloid HT recipients. In addition to these 16 patients, two patients underwent combined heart-lung transplantation. A strategy of delayed ASCT 1-year post-HT for patients with AL amyloidosis is feasible, safe, and associated with comparable outcomes to those undergoing an earlier ASCT strategy.

Long-Term Survival in Bilateral Lung Transplantation for Scleroderma-Related Lung Disease

BACKGROUND

Lung disease is the leading cause of morbidity and death in scleroderma patients, but scleroderma is often considered a contraindication to lung transplantation because of concerns for worse outcomes. We evaluated whether 5-year survival in scleroderma patients after lung transplantation differed from other patients with restrictive lung disease.

METHODS

This was a single-center, retrospective cohort study of all patients undergoing bilateral lung transplantation for scleroderma-related pulmonary disease between January 2006 and December 2014. This cohort was compared with patients undergoing bilateral lung transplantation for nonscleroderma group D restrictive disease. Primary outcomes reported were 1-year and 5-year survival. Diagnoses were identified by United Network of Organ Sharing listing and were confirmed by clinical examination and prelisting workup.

RESULTS

We compared 26 patients who underwent BLT for scleroderma and 155 patients who underwent BLT for group D restrictive disease. Overall, the nonscleroderma cohort was younger, with lower lung allocation score but no difference in functional status. Donor characteristics were not different between the cohorts. Survival at 1 year was not different (73.1% vs 80.0%, p = 0.323). Long-term survival at 5 years was also not significantly different (65.4% vs 66.5%, p = 0.608). Multivariate Cox proportional hazards analysis found no differences in survival between scleroderma and nonscleroderma group D restrictive disease (hazard ratio, 2.19; p = 0.122).

CONCLUSIONS

Despite being at high risk for extrapulmonary complications, patients undergoing bilateral lung transplantation for scleroderma have similar 1-year and 5-year survival as those with restrictive lung disease. Transplantation is a reasonable treatment option for a carefully selected population of candidates.

Left Ventricular Assist Device Implantation After Intracardiac Parachute Device Removal

Left ventricular assist device implantation is a proven and efficient modality for the treatment of end-stage heart failure. Left ventricular assist device versatility as a bridge to heart transplantation or destination therapy has led to improved patient outcomes with a concomitant rise in its overall use. Other less invasive treatment modalities are being developed to improve heart function and morbidity and mortality for the heart failure population. Percutaneous ventricular restoration is a new investigational therapy that deploys an intracardiac parachute to wall off damaged myocardium in patients with dilated left ventricles and ischemic heart failure. Clinical trials are under way to test the efficacy of percutaneous ventricular restoration using the parachute device. This review describes our encounter with the parachute device, its explantation due to refractory heart failure, and surgical replacement with a left ventricular assist device.

Persistent blood stream infection in patients supported with a continuous-flow left ventricular assist device is associated with an increased risk of cerebrovascular accidents

BACKGROUND

Common adverse events in patients supported with Continuous-flow left ventricular assist devices (CF-LVAD) include infections and cerebrovascular accidents (CVA). Some studies have suggested a possible association between blood stream infection (BSI) and CVA.

METHODS AND RESULTS

Medical records of patients who received Heartmate II (HMII) CF-LVADs in 2008-2012 at a single center were reviewed. CVA was categorized as either hemorrhagic (HCVA) or ischemic (ICVA). BSI was divided into persistent (pBSI) and nonpersistent (non-pBSI). pBSI was defined as BSI with the same organism on repeated blood culture >72 hours from initial blood culture despite antibiotics. Univariate and multivariate analyses were performed to determine predictors. A total of 149 patients had HMII implanted; 76% were male, and the overall mean age was 55.4 ± 13 years. There were a total of 19 (13%) patients who had CVA (7 HCVA and 12 ICVA) at a median of 295 days (range 5-1,096 days) after implantation. There were a total of 28 (19%) patients with pBSI and 17 (11%) patients with non-pBSI. Patients with pBSI had a trend toward greater BMI (31 kg/m(2) vs 27 kg/m(2); P = .09), and longer duration of support (1,019 d vs 371 d; P < .001) compared with those with non-pBSI. Persistent BSI was associated with an increased risk of mortality and with all-cause CVA on multivariate analysis (odds ratio [OR] 5.97; P = .003) as well as persistent Pseudomonas aeruginosa infection (OR 4.54; P = .048).

CONCLUSIONS

Persistent BSI is not uncommon in patients supported by CF-LVAD and is highly associated with all-cause CVA and increased all-cause mortality.

Microporous polysaccharide hemosphere absorbable hemostat use in cardiothoracic surgical procedures

Background

Topical hemostatic agents are used to reduce bleeding and transfusion need during cardiothoracic surgery. We report our experience with Arista® AH Absorbable Hemostatic Particles (Arista® AH), a novel plant-based microporous polysaccharide hemostatic powder.

Methods

Data were retrospectively collected for patients (n = 240) that received cardiothoracic surgery at our institution from January 2009 to January 2013 with (n = 103) or without (n = 137) the use of Arista® AH. Endpoints included protamine to skin closure time (hemostasis time), cardiopulmonary bypass time, quantity of Arista® AH applied, intraoperative blood product usage, intraoperative blood loss, chest tube output 48 hours postoperatively, blood products required 48 hours postoperatively, length of stay in the intensive care unit, 30-day morbidity, and 30-day mortality.

Results

240 patients (176 M: 64 F) underwent 240 cardiothoracic procedures including heart transplantation (n = 53), cardiac assist devices (n = 113), coronary artery bypass grafts (n = 20), valve procedures (n = 19), lung transplantation (n = 17), aortic dissection (n = 8), and other (n = 10). Application of Arista® AH led to significant reduction in hemostasis time versus the untreated control group (Arista® AH: 93.4 ± 41 min. vs. Control: 107.6 ± 56 min., p = 0.02). Postoperative chest tube output in the first 48 hours was also significantly reduced (Arista® AH: 1594 ± 949 mL vs. Control: 2112 ± 1437 mL, p < 0.001), as well as transfusion of packed red blood cells (Arista® AH: 2.4 ± 2.5 units vs. Control: 4.0 ± 5.1 units, p < 0.001). There was no significant difference in 30-day mortality or postoperative complications.

Conclusion

Use of Arista® AH in complex cardiothoracic surgery resulted in a significant reduction in hemostasis time, postoperative chest tube output, and need for postoperative blood transfusion.

Challenges in deactivating a total artificial heart for a patient with capacity

The use of mechanical circulatory support (MCS) devices has increased sixfold since 2006. Although there is an established legal and ethical consensus that patients have the right to withdraw and withhold life-sustaining interventions when burdens exceed benefits, this consensus arose prior to the widespread use of MCS technology and is not uniformly accepted in these cases. There are unique ethical and clinical considerations regarding MCS deactivation. Our center recently encountered the challenge of an awake and functionally improving patient with a total artificial heart (TAH) who requested its deactivation. We present a narrative description of this case with discussion of the following questions: (1) Is it ethically permissible to deactivate this particular device, the TAH? (2) Are there any particular factors in this case that are ethical contraindications to proceeding with deactivation? (3) What are the specific processes necessary to ensure a compassionate and respectful deactivation? (4) What proactive practices could have been implemented to lessen the intensity of this case's challenges? We close with a list of recommendations for managing similar cases.

A simplified echocardiographic technique for detecting continuous-flow left ventricular assist device malfunction due to pump thrombosis

BACKGROUND

Malfunction of a continuous-flow left ventricular assist device (CF-LVAD) due to device thrombosis is a potentially life-threatening event that currently presents a diagnostic challenge. We aimed to propose a practical echocardiographic assessment to diagnose LVAD malfunction secondary to pump thrombosis.

METHODS

Among 52 patients implanted with a CF-LVAD from a single center who underwent echocardiographic pump speed-change testing, 12 had suspected pump thrombosis as determined by clinical, laboratory, and/or device parameters. Comprehensive echocardiographic evaluation was performed at baseline pump speed and at each 1,000-rpm interval from the low setting of 8,000 rpm to the high setting of 11,000 rpm in 11 of these patients.

RESULTS

Receiver operating characteristic curves and stepwise logistic regression analyses showed that the best diagnostic parameters included changes in the LV end-diastolic diameter (<0.6 cm), aortic valve opening time (<80 msec), and deceleration time of mitral inflow (<70 msec) from lowest to highest pump speed. One parameter was predictive of pump malfunction, with 100% sensitivity and 89% specificity, whereas 2 of 3 parameters increased the sensitivity to 100% and specificity to 95%.

CONCLUSIONS

The 3 echocardiographic variables of measured changes in LV end-diastolic diameter, aortic valve opening time, and deceleration time of mitral inflow between the lowest (8,000 rpm) and highest pump speed settings (11,000 rpm) during echo-guided pump speed-change testing appear highly accurate in diagnosing device malfunction in the setting of pump thrombosis among patients supported with CF-LVAD. Further investigation is warranted to create and validate a prediction score.

Ventricular assist devices (VAD) therapy: new technology, new hope?

Ventricular assist devices are commonly utilized in the treatment of end-stage heart failure. Advances in continuous flow technology have improved efficiency, size, implantability, extended support, and overall patient outcomes. This has led to an expanded role of left ventricular assist device (LVAD) clinical use and applications. This review describes the advances and current state of LVAD devices and provides a future outlook for this technology.

Myocardial regeneration therapy for ischemic cardiomyopathy with cyclin A2

OBJECTIVE

Heart failure therapies ranging from revascularization to remodeling to replacement are variably effective. Theoretically, endogenous repair via myocardial regeneration would be an ideal therapy. This study examined the ability to initiate regeneration by adenoviral-mediated expression of the cell cycle regulator cyclin A2. Our prior studies have demonstrated robust cyclin A2 transgene expression and marked antiphosphorylated histone H3 activity with this strategy, indicating the induction of cardiomyocyte mitosis.

METHODS

Adult male, Lewis rats underwent left anterior descending coronary artery ligation followed by intramyocardial delivery of either cyclin A2 adenoviral vector (n = 8) or empty adeno-null vector as a control (n = 8) into the peri-infarct border zone. In vivo myocardial function was analyzed by echocardiography and invasive left ventricular pressure catheter at 6 weeks, when the animals are traditionally in heart failure. Hearts were explanted for immunoblotting and left ventricular geometric analysis. Cellular proliferation was assessed by proliferating cellular nuclear antigen expression.

RESULTS

Cyclin A2 hearts exhibited improved left ventricular function as compared with controls including enhanced cardiac output (32 +/- 3.3 vs 26 +/- 5.0 mL/min, P < .05), stroke volume (0.16 +/- 0.04 vs 0.11 +/- 0.04 mL, P < .05), ejection fraction (72% +/- 7.4% vs 46.% +/- 8.5%, P < .05), fractional shortening (35% +/- 5.4% vs 19% +/- 4.3%, P < .002), maximum pressure (72 +/- 9.3 vs 61 +/- 2.9 mm Hg, P < .05), and end-systolic pressure (67 +/- 7.0 vs 55 +/- 7.0 mm Hg, P < .05). Enhanced myocardial preservation was demonstrated by enhanced left ventricular border zone wall thickness. Increased myocardial proliferation was evidenced by increased expression of proliferating cell nuclear antigen expression in cyclin A2-treated hearts.

CONCLUSIONS

In failing hearts, targeted delivery of cyclin A2 improves hemodynamic function, as measured by echocardiography and pressure catheter analysis, preserves ventricular wall thickness, and may serve as an ideal myocardial regenerative therapy.

Combined DOR ventriculoplasty and aortic valve replacement in the treatment of post infarction ventricular aneurysm and aortic regurgitation

There has been only one other case of endoventricular circular patch plasty performed in conjunction with aortic valve replacement reported in the literature. We present the unique case of a patient suffering from congestive heart failure due to both post-infarct aortic regurgitation and ventricular aneurysm along with his successful surgical treatment.

Neovasculogenic Therapy to Augment Perfusion and Preserve Viability in Ischemic Cardiomyopathy

BACKGROUND

Ischemic cardiomyopathy is a global health concern with limited therapy. We recently described endogenous revascularization utilizing granulocyte-macrophage colony stimulating factor (GMCSF) to induce endothelial progenitor cell (EPC) production and intramyocardial stromal cell-derived factor-1alpha (SDF) as a specific EPC chemokine. The EPC-mediated neovascularization and enhancement of myocardial function was observed. In this study we examined the regional biologic mechanisms underlying this therapy.

METHODS

Lewis rats underwent left anterior descending coronary artery (LAD) ligation and developed ischemic cardiomyopathy over 6 weeks. Three weeks after ligation, the animals received either subcutaneous GMCSF and intramyocardial SDF injections or saline injections as control. Six weeks after LAD ligation circulating EPC density was studied by flow cytometry. Quadruple immunofluorescent vessel staining for mature, proliferating vasculature was performed. Confocal angiography was utilized to identify fluorescein lectin-lined vessels to assess perfusion. Ischemia reversal was studied by measuring myocardial adenosine triphosphate (ATP) levels. Myocardial viability was assayed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling detection of apoptosis and quantitation of myofilament density.

RESULTS

The GMCSF/SDF therapy enhanced circulating leukocyte (13.1 +/- 4.5 x 10(6) vs 3.1 +/- 0.5 x 10(6)/cc, p = 0.001, n = 6) and EPC (14.2 +/- 6.6 vs 2.2 +/- 2.1/cc, p = 0.001, n = 6) concentrations. Tetraimmunofluorescent labeling demonstrated enhanced stable vasculature with this therapy (39.2 +/- 8.1 vs 25.4 +/- 5.1%, p = 0.006, n = 7). Enhanced perfusion was shown by confocal microangiography of borderzone lectin-labeled vessels (28.2 +/- 5.4 vs 11.5 +/- 3.0 vessels/high power field [hpf], p = 0.00001, n = 10). Ischemia reversal was demonstrated by enhanced cellular ATP levels in the GMCSF/SDF borderzone myocardium (102.5 +/- 31.0 vs 26.9 +/- 4.1 nmol/g, p = 0.008, n = 5). Borderzone cardiomyocyte viability was noted by decreased apoptosis (3.2 +/- 1.4% vs 5.4 +/- 1.0%, p = 0.004, n = 10) and enhanced cardiomyocyte density (40.0 +/- 5.6 vs 27.0 +/- 6 myofilaments/hpf, p = 0.01, n=10).

CONCLUSIONS

Endogenous revascularization for ischemic cardiomyopathy utilizing GMCSF EPC upregulation and SDF EPC chemokinesis upregulates circulating EPCs, enhances vascular stability, and augments myocardial function by enhancing perfusion, reversing cellular ischemia, and increasing cardiomyocyte viability.

Fructose 1,6-diphosphate administration attenuates post-ischemic ventricular dysfunction

BACKGROUND

Cardiomyocyte energy production during ischemia depends upon anaerobic glycolysis inefficiently yielding two ATP per glucose. Substrate augmentation with fructose 1,6-diphosphate (FDP) bypasses the ATP consuming steps of glucokinase and phosphofructokinase thus yielding four ATP per FDP. This study evaluated the impact of FDP administration on myocardial function after acute ischemia.

METHODS

Male Wistar rats, 250-300 g, underwent 30 min occlusion of the left anterior descending coronary artery followed by 30 min reperfusion. Immediately prior to both ischemia and reperfusion, animals received an intravenous bolus of FDP or saline control. After 30 min reperfusion, myocardial function was evaluated with a left ventricular intracavitary pressure/volume conductance microcatheter. For bioenergetics studies, myocardium was isolated at 5 min of ischemia and assayed for ATP levels.

RESULTS

Compared to controls (n=8), FDP animals (n=8) demonstrated significantly improved maximal left ventricular pressure (100.5+/-5.4 mmHg versus 69.1+/-1.9 mmHg; p<0.0005), dP/dt (5296+/-531 mmHg/s versus 2940+/-175 mmHg/s; p<0.0028), ejection fraction (29.1+/-1.7% versus 20.4+/-1.4%; p<0.0017), and preload adjusted maximal power (59.3+/-5.0 mW/microL(2) versus 44.4+/-4.6 mW/microL(2); p<0.0477). Additionally, significantly enhanced ATP levels were observed in FDP animals (n=5) compared to controls (n=5) (535+/-156 nmol/g ischemic tissue versus 160+/-9.0 nmol/g ischemic tissue; p<0.0369).

CONCLUSIONS

The administration of the glycolytic intermediate, FDP, by intravenous injection, resulted in significantly improved myocardial function after ischemia and improved bioenergetics during ischemia.