Percutaneous closure of the aortic valve as a bridge to heart transplantation to treat severe aortic insufficiency after ventricular assist device

Aortic insufficiency (AI) following rotary left ventricular assist device (LVAD) implantation is an increasingly common problem with inadequately defined treatment options. Percutaneous transcatheter (PTC) closure of the aortic valve (AV) has been described as a potential nonsurgical approach. Alternatively, we present a case of decompensated heart failure due to de novo severe AI following LVAD in which successful PTC closure of the AV resolved the severe AI and allowed for clinical recovery and stability for more than 10 months as a bridge to heart transplantation. © 2014 Wiley Periodicals, Inc.     

Slope of the Anterior Mitral Valve Leaflet: A New Measurement of Left Ventricular Unloading for Left Ventricular Assist Devices and Systolic Dysfunction

Left ventricular assist device (LVAD)-supported patients are evaluated routinely with use of transthoracic echocardiography. Values of left ventricular unloading in this unique patient population are needed to evaluate LVAD function and assist in patient follow-up.We introduce a new M-mode measurement, the slope of the anterior mitral valve leaflet (SLAM), and compare its efficacy with that of other standard echocardiographically evaluated values for left ventricular loading, including E/e′ and pulmonary artery systolic pressures. Average SLAM values were determined retrospectively for cohorts of random, non-LVAD patients with moderately to severely impaired left ventricular ejection fraction (LVEF) (<0.35, n=60). In addition, pre- and post-LVAD implantation echocardiographic images of 81 patients were reviewed.The average SLAM in patients with an LVEF <0.35 was 11.6 cm/s (95% confidence interval, 10.4–12.8); SLAM had a moderately strong correlation with E/e′ in these patients. Implantation of LVADs significantly increased the SLAM from 7.3 ± 2.44 to 14.7 ± 5.01 cm/s (n=42, P <0.0001). The LVAD-supported patients readmitted for exacerbation of congestive heart failure exhibited decreased SLAM from 12 ± 3.93 to 7.3 ± 3.5 cm/s (n=6, P=0.041). In addition, a cutpoint of 10 cm/s distinguished random patients with LVEF <0.35 from those in end-stage congestive heart failure (pre-LVAD) with an 88% sensitivity and a 55% specificity.Evaluating ventricular unloading in LVAD patients remains challenging. Our novel M-mode value correlates with echocardiographic values of left ventricular filling in patients with moderate-to-severe systolic function and dynamically improves with the ventricular unloading of an LVAD.     

Value of Serial Echo‐Guided Ramp Studies in a Patient with Suspicion of Device Thrombosis after Left Ventricular Assist Device Implantation

Thrombus formation inside of the pump is a major cause for device malfunction following the left ventricular assist device (LVAD) implantation. We recently established a novel ramp test protocol facilitating continuous bedside echo monitoring to optimize LVAD function and diagnosing device malfunctions. We describe a case of 29‐year‐old woman undergoing HeartMate II LVAD implantation, in whom serial ramp studies were used to diagnose intra‐device thrombus after device implantation. The 1st ramp study at postoperative day (POD) 26 revealed adequate reduction in ventricular size according to the increase in LVAD speed (left ventricular end‐diastolic diameter [LVEDD] at minimum and maximum speeds, 68 and 37 mm, respectively). The patient was discharged home and received routine anticoagulation maintenance therapy. However, a 2nd ramp test was performed on POD 56 due to increased lactase dehydrogenase and brain natriuretic peptide levels and showed marked increase in left ventricle (LV) chamber size without adequate response to the LVAD speed changes (LVEDD at minimum and maximum speeds, 88 and 76 mm, respectively). Given the suspicion for partial pump thrombosis, the patient was immediately hospitalized and received intravenous heparin infusion. After the optimization of the intensive anticoagulation therapy, the patient underwent a 3rd ramp study, which showed a remarkable improvement of the adequate response to LVAD speed changes. The patients eventually underwent cardiac transplant successfully, and the partial clot was found inside of the pump. This case demonstrates the usefulness of serial ramp studies in patients who are suspected to have device thrombosis.     

Subcutaneous Implantable Cardioverter-Defibrillator Implantation in a Patient with a Left Ventricular Assist Device Already in Place

A 56-year-old man with ischemic cardiomyopathy, a biventricular implantable cardioverter-defibrillator (ICD), and a left ventricular assist device (LVAD) developed a pocket hematoma and infection after an ICD generator change. The biventricular ICD was extracted, and the patient was given a full course of antibiotics. Because he had no indications for bradycardia pacing or biventricular pacing, he was implanted with a subcutaneous ICD under full anticoagulation. There was no interference in sensing or shock delivery from the ICD. The LVAD readings were unchanged during and after the procedure. The patient had an uneventful postoperative course, and both devices were functioning normally.To our knowledge, this is the first reported case of the implantation of a subcutaneous ICD in the presence of an LVAD. This report illustrates that both devices can be implanted successfully in the same patient. In addition, the subcutaneous ICD minimizes the risk of bloodstream infections, which can be fatal in patients who have life-supporting devices such as an LVAD.     

Right ventricular failure following placement of a percutaneous left ventricular assist device

Right ventricular (RV) dysfunction following surgical implantation of a left ventricular assist device (LVAD) is a well-documented phenomenon, and it is associated with poor outcomes. We are reporting a 25-year-old male patient who presented to the hospital with flu-like symptoms, hypotension and acute hypoxic respiratory failure. The patient's Laboratory data was significant for elevated troponin, and his Chest X-ray showed acute pulmonary edema. Echocardiogram revealed reduced left ventricular (LV) ejection fraction and normal RV function. Coronary angiography was normal, and the cardiac index was 1.3?L/min/m². Impella 5.0 (Abiomed, MA) was placed through the left axillary artery graft and 4.5?L/min flow was achieved with an improvement in blood pressure. Thirty minutes later, he developed hypotension, the device flow dropped to 3.0?L/min, and right atrial pressure increased. The Pulmonary artery pulsatility index was consistent with RV failure. Possible causes of RV failure include unmasking of RV dysfunction with high LVAD flow and altered RV geometry due to ventricular septum shift. Impella RP (Abiomed, MA) was placed for RV support achieving a flow of 3.8?L/min with a significant improvement in impella LV flow, cardiac output and blood pressure (mean 90?mmHg). Ventricular support devices were weaned off on day 9. The patient was discharged on day 15. Conclusion: our case highlights the risk of RV failure following percutaneous LVAD placement. Early identification and appropriate mechanical support is imperative.     

Right Ventricular Systolic and Diastolic Function as Assessed by Speckle-Tracking Echocardiography Improve With Prolonged Isolated Left Ventricular Assist Device Support

BackgroundRight ventricular (RV) failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) implantation. Whether RV function deteriorates with prolonged LVAD support is unknown. Speckle-tracking echocardiography provides a sensitive, noninvasive, reproducible, and quantitative assessment of RV systolic and diastolic function.MethodsEchocardiograms were retrospectively reviewed from before and after implantation of a Heartmate II LVAD. Speckle-tracking analysis was performed to measure RV longitudinal systolic strain, strain rate, and diastolic strain rate for each patient at baseline and over discrete time periods after LVAD implantation.ResultsSeventeen patients were included in the analysis, with an average follow-up after LVAD implantation of 234 ± 125 days. RV systolic strain improved in 15 patients, decreasing from −7.4 ± 2.3% to −9.7 ± 3.3% after LVAD (P = .026). Systolic strain rate improved in 11 patients, decreasing from −0.67 ± 0.25%/s to −0.96 ± 0.36%/s (P = .011). RV diastolic strain rate improved in 12 patients, increasing from 0.70 ± 0.33%/s to 1.02 ± 0.40%/s (P = .016).ConclusionsChronic LVAD support improves RV systolic and diastolic function in LVAD patients who did not require an RV assist device. Speckle-tracking echocardiography may offer a noninvasive technique for identifying and monitoring improvements in RV function in LVAD patients.     

Use of implantable cardioverter defibrillators in patients with left ventricular assist devices

Patients with left ventricular assist devices (LVADs) are at high risk of sustained ventricular arrhythmias, but these may be remarkably well tolerated and the association with sudden death is unclear. Many patients who receive an LVAD already have an implantable cardioverter defibrillator (ICD). While it is standard practice to reactivate a previously implanted ICD in an LVAD recipient, this should include discussion of the revised risks and benefits of ICD therapy following LVAD implantation. In particular, patients should be warned that they might receive a significant number of ICD shocks that may not be life saving. When ICDs are reactivated, device programming should minimize the risk of repeated shocks for non-sustained or well-tolerated ventricular arrhythmias. Implantation of a primary prevention ICD after implantation of an LVAD is not supported by current evidence, poses potential risks, and should be the subject of a clinical trial before it becomes standard practice.     

Recurrent Takotsubo Cardiomyopathy Related to Recurrent Thyrotoxicosis

Takotsubo cardiomyopathy, or transient left ventricular apical ballooning syndrome, is characterized by acute left ventricular dysfunction caused by transient wall-motion abnormalities of the left ventricular apex and mid ventricle in the absence of obstructive coronary artery disease. Recurrent episodes are rare but have been reported, and several cases of takotsubo cardiomyopathy have been described in the presence of hyperthyroidism. We report the case of a 55-year-old woman who had recurrent takotsubo cardiomyopathy, documented by repeat coronary angiography and evaluations of left ventricular function, in the presence of recurrent hyperthyroidism related to Graves disease. After both episodes, the patient''s left ventricular function returned to normal when her thyroid function normalized. These findings suggest a possible role of thyroid-hormone excess in the pathophysiology of some patients who have takotsubo cardiomyopathy.     

Continuous-Flow Left Ventricular Assist Device Explantation After More Than 5 Years of Circulatory Support and Ventricular Reconditioning

Continuous-flow left ventricular assist devices have proved to be effective, durable, life-saving tools in patients with end-stage heart failure. However, because of the risks associated with mechanical circulatory support (including stroke, infection, gastrointestinal bleeding, and device malfunction), the optimal goal of device therapy is myocardial recovery and device removal. Ventricular reconditioning and pump explantation after continuous-flow support have been reported; however, little is known about variables that govern the pace and degree of myocardial response in patients who experience such recovery. We describe our long-term pump-weaning strategy for a 25-year-old man who had a continuous-flow device implanted and then needed more than 5 years of support from it before developing cardiac reserve sufficient to enable pump explantation. To our knowledge, this is the longest period of uninterrupted continuous-flow device support to end in successful pump deactivation and a return to medical therapy. This case highlights the importance of actively and persistently pursuing a device-weaning strategy in all patients who need left ventricular assist device therapy.     

Cardiac stereotactic radiation therapy for refractory ventricular arrhythmias in patients with left ventricular assist devices

Left ventricular assist device (LVAD) implantation is an established treatment for patients with advanced heart failure refractory to medical therapy. However, the incidence of ventricular arrhythmias (VAs) is high in this population, both in the acute and delayed phases after implantation. About one-third of patients implanted with an LVAD will experience sustained VAs, predisposing these patients to worse outcomes and complicating patient management. The combination of pre-existing myocardial substrate and complex electrical remodeling after LVAD implantation account for the high incidence of VAs observed in this population. LVAD patients presenting VAs refractory to antiarrhythmic therapy and catheter ablation procedures are not rare. In such patients, treatment options are extremely limited. Stereotactic body radiation therapy (SBRT) is a technique that delivers precise and high doses of radiation to highly defined targets, reducing exposure to adjacent normal tissue. Cardiac SBRT has recently emerged as a promising alternative with a growing number of case series reporting the effectiveness of the technique in reducing the VA burden in patients with arrhythmias refractory to conventional therapies. The safety profile of cardiac SBRT also appears favorable, even though the current clinical experience remains limited. The use of cardiac SBRT for the treatment of refractory VAs in patients implanted with an LVAD are even more scarce. This review summarizes the clinical experience of cardiac SBRT in LVAD patients and describes technical considerations related to the implementation of the SBRT procedure in the presence of an LVAD.     

Right Ventricular Sarcoidosis: Is It Time for Updated Diagnostic Criteria?

A 55-year-old woman with a history of complete heart block, atrial flutter, and progressive right ventricular failure was referred to our tertiary care center to be evaluated for cardiac transplantation. The patient''s clinical course included worsening right ventricular dysfunction for 3 years before the current evaluation. Our clinical findings raised concerns about arrhythmogenic right ventricular cardiomyopathy. Noninvasive imaging, including a positron emission tomographic scan, did not reveal obvious myocardial pathologic conditions. Given the end-stage nature of the patient''s right ventricular failure and her dependence on inotropic agents, she underwent urgent listing and subsequent heart transplantation. Pathologic examination of the explanted heart revealed isolated right ventricular sarcoidosis with replacement fibrosis. Biopsy samples of the cardiac allograft 6 months after transplantation showed no recurrence of sarcoidosis. This atypical presentation of isolated cardiac sarcoidosis posed a considerable diagnostic challenge. In addition to discussing the patient''s case, we review the relevant medical literature and discuss the need for updated differential diagnostic criteria for end-stage right ventricular failure that mimics arrhythmogenic right ventricular cardiomyopathy.     

Right ventricular dysfunction in patients undergoing left ventricular assist device implantation: predictors, management, and device utilization

Nonreversible failure of the right ventricle is seen in 0.04% to 0.1% of postcardiotomy cases. The incidence of right ventricular dysfunction after left ventricular assist device (LVAD) implantation that fails to resolve in the operating room is reported to be as frequent as 20% to 50% and imposes a considerable burden in terms of postoperative morbidity and mortality. Should this syndrome supervene, the mortality of an LVAD operation increases from 19% to 43%. Although most patients can be maintained with prolonged inotropic support, 10% to 15% may require implantation of a separate right ventricular support device.     

Regression of Left Ventricular Mass after Implantation of the Sutureless 3f Enable Aortic Bioprosthesis

Left ventricular hypertrophy in aortic stenosis is considered a compensatory response for the maintenance of systolic function but a risk factor for cardiac morbidity and death. We investigated the degree of left ventricular mass regression after implantation of the sutureless Medtronic 3f Enable^® Aortic Bioprosthesis.We studied 19 patients who, from May 2010 through July 2011, underwent isolated aortic valve replacement with the 3f Enable bioprosthetic valve, with clinical and echocardiographic follow-up at 6 months. The mean age was 77.1 ± 5.1 years (range, 68–86 yr); 14 patients were women (73.7%); and the mean logistic EuroSCORE was 15.4% ± 11.8%. Echocardiography was performed preoperatively, at discharge, and at 6 months'' follow-up. The left ventricular mass was calculated by means of the Devereux formula and indexed to body surface area.The left ventricular mass index decreased from 146.1 ± 47.6 g/m² at baseline to 118.1 ± 39.8 g/m² at follow-up (P=0.003). The left ventricular ejection fraction did not change significantly. The mean transaortic gradient decreased from 57.3 ± 14.2 mmHg at baseline to 12.3 ± 4.6 mmHg at discharge and 12.2 ± 5.3 mmHg at follow-up (P <0.001), and these decreases were accompanied by substantial clinical improvement. No moderate or severe paravalvular leakage was present at discharge or at follow-up.In isolated aortic stenosis, aortic valve replacement with the 3f Enable bioprosthesis results in significant regression of left ventricular mass at 6 months'' follow-up. However, this regression needs to be verified by long-term echocardiographic follow-up.     

Catheter ablation for atrial fibrillation in left ventricular assist device: A case report

Introduction:Mechanical circulatory support such as the left ventricular assist device (LVAD) has become widely implemented in the treatment of end-stage heart failure, whether as bridge-to-transplant or as destination therapy. The hemodynamic effects of arrhythmia on LVADs and its management are significant in determining the long-term outcome of these patients. Both atrial arrhythmia and ventricular arrhythmia are commonly seen after implantation of the device. There are no strict guidelines, however, on the need for intensive management of arrhythmias in LVAD. In this case report, we present a patient with new onset atrial fibrillation after LVAD implantation which leads to acute decompensating heart failure. The patient was treated with catheter ablation. The intervention demonstrated positive outcomes for this patient.Patient concerns:The patient was a Korean male, who presented with dyspnea, fatigue and generalized edema after persistent atrial fibrillation precipitated by implantation of the left ventricular assist device.Diagnosis:The patient was diagnosed with acute decompensating heart failure that was aggravated by recurrent atrial arrhythmia.Intervention:We attempted to relieve symptoms of right ventricular dysfunction by method of strict rhythm control in this patient. The patient underwent radiofrequency catheter ablation for recurrent atrial fibrillation.Outcome:The patient showed improved clinical symptoms, BNP levels, and echocardiogram parameters immediately after the procedure as well as during long term outpatient follow up.Conclusion:In this case report, we present the first successful case in Korea of atrial fibrillation in LVAD treated with catheter ablation. This case suggests setting catheter ablation as a routine first-line treatment for atrial arrhythmia in LVAD patients, especially when the arrhythmia predisposes the patient at risk for decompensating heart failure.     

Myocardial histological changes in dilated cardiomyopathy during a long-term left ventricular assist device support

Summary As the myocardium in patients with dilated cardiomyopathy (DCM) is deteriorating progressively, resulting in a decrease in left ventricular function, patients with end-stage DCM may require implantation of a left ventricular assist device (LVAD) unless they undergo heart transplantation. Although LVAD has been reported to provide excellent hemodynamic support, no data are currently available about the effects of long-term LVAD support on the myocardium in patients with DCM. We describe two patients with end-stage DCM who underwent LVAD implantation and were supported with LVAD for 524 and 245 days, respectively. Serial myocardial biopsies showed increases in myocardial cell diameter and intercellular fibrosis, despite excellent hemodynamic support by LVAD. These data suggest that the myocardium in patients with end-stage DCM deteriorates progressively, even if the preload of the left ventricle is reduced by LVAD.     

Extracorporeal membrane oxygenation and left ventricular assist device: a case of double mechanical bridge

A 14-year-old boy with dilated cardiomyopathy with cardiac arrest was successfully implanted with a left ventricular assist device (LVAD) after 6-day extracorporeal membrane oxygenation (ECMO). He had multiple organ failure at the initiation of ECMO, but the failed organs recovered during assisted circulation, leading to LVAD implantation. This case showed the advantages of the "double bridge" such as: (1) quick and easy installation for acute cardiogenic shock, (2) providing intervention time for complications refractory to LVAD implantation, and (3) providing evaluation time for potential LVAD implantation and transplant candidates. Received: December 21, 2001 / Accepted: February 1, 2002     

The dilemma of a left ventricular assist device explantation: a decision analysis

BACKGROUND: Left ventricular assist devices (LVADs) are an important adjunct to the management of end-stage heart failure patients. Uncertainty remains regarding whether to remove an LVAD in a clinically stable, asymptomatic patient who displays signs of ventricular recovery. OBJECTIVES: To evaluate, from a patient's perspective, the quality-adjusted life expectancy of an LVAD explantation. METHODS: A Markov state transition model was used to assess the benefits of two strategies: remove an LVAD or continue the LVAD support. Effectiveness was measured in quality-adjusted life months. Utility and probability scores were derived from the literature and expert opinion. The base case focused on a 35-year-old man with dilated cardiomyopathy, an implantable LVAD and signs of ventricular recovery, with New York Heart Association class I heart failure symptoms. RESULTS: In the base case, continuing LVAD support was strongly preferred and improved quality-adjusted life expectancy by nine quality-adjusted life months. In sensitivity analyses for the utility post-transplant, removal of the device would have been preferred if the utility was less than 0.7. The model was also sensitive to the probability of late complications post-LVAD implantation. As the probability of complications increased (greater than 28%), the preferred strategy was to remove the LVAD. CONCLUSIONS: Continuing LVAD support in asymptomatic patients with signs of ventricular recovery appears to be the preferred strategy for conveying greater quality-adjusted life months compared with LVAD explantation. As the probability of complications after LVAD implantation increases, the preferred strategy is to remove the LVAD.     

Left Ventricular Assist Device Support and Longitudinal Sleeve Gastrectomy Combined With Diet in Bridge to Heart Transplant

Combining left ventricular assist device (LVAD) implantation and longitudinal sleeve gastrectomy may enable patients with morbid obesity to lose enough weight for heart transplant eligibility. In a retrospective study, we evaluated long-term outcomes of patients with body mass indexes ≥35 who underwent LVAD implantation and longitudinal sleeve gastrectomy during the same hospitalization (from January 2013 through July 2018) and then adhered to a dietary protocol. We included 22 patients (mean age, 49.9 ± 12.5 yr; mean preoperative body mass index, 43.3 ± 6.2). Eighteen months after gastrectomy, all 22 patients were alive, and 16 (73%) achieved a body mass index of less than 35. Myocardial recovery in 2 patients enabled LVAD removal. As of October 2020, 10 patients (45.5%) had undergone heart transplantation, 5 (22.3%) were waitlisted, 5 (22.3%) still had a body mass index ≥35, and 2 (9%) had died.With LVAD support, longitudinal sleeve gastrectomy, and dietary protocols, most of our patients with morbid obesity and advanced heart failure lost enough weight for transplant eligibility. Support from physicians and dietitians can maximize positive results in these patients.     

右心室衰竭

Right ventricular （RV） failure is a significant issue in cardiac surgery, including congenital heart disease, pulmonary thromboembolism, heart transplantation and left ventricular assist device implantation （LVAD）. However, RV performance is often difficult to evaluate because it is difficult to measure RV volume. The lineality of preload recruitable stroke work relationship has been shown in previous experiments and clinical studies in the left ventricle and it has become one of the most reliable indexes to evaluate ventricular function. Applications of these relationships to the RV have been done but there has been many limitations.     

Adverse interaction between a left ventricular assist device and an implantable cardioverter defibrillator

An increasing number of patients have a coexisting implantable cardioverter defibrillator (ICD) and left ventricular assist device (LVAD) to treat ventricular arrhythmias and refractory heart failure, respectively. To date, there have been no published reports of negative interactions between these devices that have impacted appropriate ICD or LVAD function. In this case report, we describe a patient with an LVAD-ICD interaction that necessitated replacement of the implantable defibrillator.