Echocardiography in the Management of Patients with Left Ventricular Assist Devices: Recommendations from the American Society of Echocardiography

Medium-term outcomes of concomitant aortic valve repair in patients with continuous-flow left ventricular assist device

OBJECTIVE

To analyze the development of aortic insufficiency in patients who received central aortic valve repair when undergoing continuous-flow left ventricular assist device implantation.

METHODS

We conducted a retrospective review of patients who underwent implantation with HeartMate II or 3 (Abbott Laboratories) between 2004 and 2022. Ninety-four patients were excluded from analysis for history of aortic valve procedures, a bicuspid aortic valve, baseline trace aortic insufficiency, or other concomitant aortic valve procedure. Patients who had mild or greater aortic insufficiency had concomitant aortic valve repair. Clinical characteristics, serial echocardiograms, and outcomes were determined.

RESULTS

Of the 656 patients who underwent HeartMate II or 3 implantation, 105 patients (59 HeartMate II and 46 HeartMate 3) met study criteria. Median age was 68 years (60-74 years), 91.4% (n = 96) were male, 54.4% (n = 56) were White, and 68.6% (n = 72) received support as destination therapy. Preoperative aortic insufficiency degree was 54.3% (n = 57) mild, 23.8% (n = 25) mild-to-moderate, 20.0% (n = 21) moderate, 1.0% (n = 1) moderate-to-severe, and 1.0% (n = 1) severe. In hospital mortality was 5.7% (n = 6). Freedom from moderate or greater aortic insufficiency was 96.4% (95% confidence interval [CI], 92.5%-100%), 93.3% (95% CI, 87.6%-99.2%), and 91.0% (95% CI, 84.1%-98.5%) at 1-year, 2-year, and 3-year postimplantation, respectively. One patient who received a HeartMate II experienced severe aortic insufficiency and was treated with a heart transplant. Three-year survival was 63.4% (95% CI, 52.9%-75.9%).

CONCLUSIONS

Central aortic valve repair may be an effective technique to mitigate aortic insufficiency in HeartMate II and 3. A larger cohort study with longer duration of follow-up is warranted to further investigate the clinical effect.

The Year in Perioperative Echocardiography: Selected Highlights from 2024

This article is the ninth of an annual series reviewing the research highlights of the year pertaining to the subspecialty of perioperative echocardiography for the Journal of Cardiothoracic and Vascular Anesthesia. The authors thank the editor-in-chief, Dr. Kaplan, and the editorial board for the opportunity to continue this series. In most cases, these will be research articles that are targeted at the perioperative echocardiography diagnosis and treatment of patients after cardiothoracic surgery; but in some cases, these articles will target the use of perioperative echocardiography in general.

Ultrasound Assessment of Venous and Pulmonary Congestion in Left Ventricular Assist Devices Patients

BACKGROUND

A significant number of (left ventricular assist device) LVAD patients (pts) have hemodynamic-related adverse events requiring right heart catheterization (RHC). Venous and lung ultrasound is an established method for evaluating congestion in heart failure pts. This study aimed to investigate the role of these ultrasound parameters in the hemodynamic assessment of LVAD pts.

METHODS

RHC and complete echocardiography were performed on 50 consecutive LVAD pts, 12 of whom were the validation cohort. Pts were stratified based on right atrial pressure (RAP) ≥ 7 mmHg and pulmonary capillary wedge pressure (PCWP) > 15 mmHg.

RESULTS

The median LVAD follow-up time was 400 (209-900) days. Baseline characteristics were similar between high vs. normal RAP groups, except for NYHA class and renal function in the former group. High vs. normal PCWP showed a greater NYHA class and a furosemide dose. All hemodynamic parameters were significantly different in the high RAP group except for cardiac output (CO) and cardiac index (CI). In contrast, in the high PCWP group, no differences in CO, CI, and pulmonary vascular resistances were apparent. The most accurate non-invasive variable for detecting high RAP was renal venous stasis index (RVSI), receiver-operating characteristic curves for areas under the curve (AUC), 0.78 (95% CI, 0.62-0.93). Estimated left atrial pressure (LAP-eRAP) was the most accurate non-invasive value to discriminate high PCWP (AUC 0.85 95% CI 0.73-0.98).

CONCLUSION

This study found a good correlation between RAP, PWCP, and non-invasive parameters, such as RVSI and LAP-eRAP, suggesting the importance of peripheral venous ultrasound in LVAD patients.

Potential benefits of aortic valve opening in patients with left ventricular assist devices

BACKGROUND

Aortic regurgitation (AR) is a well-known cause of impaired outcome in patients with centrifugal left ventricular assist devices (cfLVADs). The failure of the aortic valve (AV) to open at least intermittently is associated with cusp remodeling, commissural fusion, and ultimately developing AR. Our aim was to characterize patients in whom AV opening (AVO) was preserved 6 months after implantation and identify determinants related to it.

METHODS AND RESULTS

We conducted standardized echocardiography and collected clinical and laboratory tests at the outpatient clinic 6 months after implantation. We classified patients into those showing intermittently opening of the AV, every 2-3 beats, or in every cycle (AVO) and those whose AV was continuously closed (NAVO). From the 219 cfLVAD implanted in our center between March 2018 and January 2020, 156 subjects were alive and on the device after 6 months. In 2 of the reviewed echocardiograms, we could not evaluate the AV. 99 patients (64%) showed AVO compared to 55 (36%) with NAVO. The first presented higher mean arterial pressure (84 ± 10 vs. 77 ± 13 mm Hg, p = 0.002), larger LV end-diastolic diameter (LVEDD 57.5 ± 12 vs. 52.7 ± 13 mm, p = 0.022), a better TAPSE (15 ± 4 vs. 13 ± 4 mm, p = 0.028), and less frequently significant AR than patients with NAVO (moderate/severe AR in 6% vs. in 20%, p = 0.042). In a multiple logistic regression, a lower NYHA Class, a larger LVEDD, and a better LV ejection fraction appeared as significant predictors of AVO. After a median follow-up of 3.2 years, we found no significant impact on survival stratifying patients by AVO (log-rank p = 0.53).

CONCLUSION

AVO was associated with better RV function, lower NYHA Class, and a lower rate of significant AR. This could indicate that AVO should be pursued in LVAD patients.

Pearls and Pitfalls of Epicardial Echocardiography for Implantation of Impella CP Devices in Ovine Models

The Impella CP is a percutaneously inserted temporary left ventricular assist device used in clinical practice and in translational research into cardiogenic shock, perioperative cardiac surgery, acute cardiac failure and mechanical circulatory support. Fluoroscopic guidance is usually used for insertion of an Impella, thus limiting insertion to within catheterization laboratories. Transthoracic, transoesophageal and intracardiac echocardiography have been reported to guide Impella CP implantation with identified specific limitations stemming from the surgical, anatomical and equipment factors. We conducted translational prospective descriptive feasibility investigation as a part of two other hemodynamic Impella studies. It showed the successful application of epicardial echocardiographic scanning for implantation of Impella CP devices in ovine models, from which details of the technique and identified pitfalls are described with practical solutions for future investigators and clinicians. Many described findings are relevant to any other echocardiographic techniques when adequate imaging of the Impella and relevant anatomical structures is achievable.

Comparison between invasive cardiac output and left ventricular assist device flow parameter

OBJECTIVES

To evaluate the correlation between left ventricular assist device flow parameter and invasive cardiac output measurements.

METHODS

We retrospectively evaluated right heart catheterization examinations performed in left ventricular assist device patients from 2 tertiary medical centres. We evaluated the correlation between cardiac output measurement methods (indirect Fick and thermodilution) and pump flow parameter using linear regression, and the agreement was graphically displayed using Bland-Altman plot technique. Clinical, echocardiographic, pump and haemodynamic parameters were compared between patients with and without discordance, defined as at least a 20% difference between measurements.

RESULTS

The study population consisted of 102 patients [median age 58 (51-64), 86% males, 17 ± 12 months post left ventricular assist device implantation] with a total of 544 measurements compared. Discordance between measurements was present in 102 of 226 (45%) comparisons between indirect Fick and pump flow and in 72 of 161 (48%) between thermodilution and pump flow. A comparison of indirect Fick and left ventricular assist device exhibited a statistical correlation of R = 0.751, and that of thermodilution and left ventricular assist device of R = 0.789. Parameters associated with the presence of discordance between cardiac output measurements included a higher rate of aortic valve opening, lower indirect Fick and higher thermodilution cardiac output. After excluding the lowest tertile of indirect Fick cardiac output values, the correlation between measurements improved (thermodilution: R = 0.879 and indirect Fick: R = 0.843, P < 0.001).

CONCLUSIONS

The current left ventricular assist device flow parameter provides an estimation of cardiac output that correlates well with indirect Fick and exhibits the strongest correlation with thermodilution. This correlation was stronger after excluding lower cardiac output values.

Extrinsic outflow graft obstruction of the HeartMate 3 LVAD: A state-of-the-art review

While notable improvements in survival, the incidence of hemocompatibility-related adverse events, hospitalizations, and cost have been demonstrated with the only commercially available durable left ventricular assist device, a category of pump malfunctions characterized by outflow graft obstruction has been noted with broader use and clinical follow-up of recipients of this technology. Of particular concern is the accumulation of acellular biodebris between the outflow graft and bend relief covering the outflow graft at its origin with the pump (which we term extrinsic outflow graft obstruction at the bend relief). This process tends to be insidious, occurs late in the postoperative course, can be challenging to diagnose, and can result in significant morbidity and mortality. Herein, we provide a review of this complication and outline diagnostic, treatment, and preventive strategies.

Aortic insufficiency in the patient on contemporary durable left ventricular assist device support: A state-of-the-art review on preoperative and postoperative assessment and management

The development of aortic insufficiency (AI) during HeartMate 3 durable left ventricular assist device (dLVAD) support can lead to ineffective pump output and recurrent heart failure symptoms. Progression of AI often comingles with the occurrence of other hemodynamic-related events encountered during LVAD support, including right heart failure, arrhythmias, and cardiorenal syndrome. While data on AI burdens and clinical impact are still insufficient in patients on HeartMate 3 support, moderate or worse AI occurs in approximately 8% of patients by 1 year and studies suggest AI continues to progress over time and is associated with increased frequency of right heart failure. The first line intervention for AI management is prevention, undertaking surgical intervention on the insufficient valve at the time of dLVAD implant and avoiding excessive device flows and hypertension during long-term support. Device speed augmentation may then be undertaken to try and overcome the insufficient lesion, but the progression of AI should be anticipated over the long term. Surgical or transcatheter aortic valve interventions may be considered in dLVAD patients with significant persistent AI despite medical management, but neither intervention is without risk. It is imperative that future studies of dLVAD support capture AI in clinical end-points using uniform assessment and grading of AI severity by individuals trained in AI assessment during dLVAD support.

Right heart failure with left ventricular assist devices: Preoperative, perioperative and postoperative management strategies. A clinical consensus statement of the Heart Failure Association (HFA) of the ESC

Right heart failure (RHF) following implantation of a left ventricular assist device (LVAD) is a common and potentially serious condition with a wide spectrum of clinical presentations with an unfavourable effect on patient outcomes. Clinical scores that predict the occurrence of right ventricular (RV) failure have included multiple clinical, biochemical, imaging and haemodynamic parameters. However, unless the right ventricle is overtly dysfunctional with end-organ involvement, prediction of RHF post-LVAD implantation is, in most cases, difficult and inaccurate. For these reasons optimization of RV function in every patient is a reasonable practice aiming at preparing the right ventricle for a new and challenging haemodynamic environment after LVAD implantation. To this end, the institution of diuretics, inotropes and even temporary mechanical circulatory support may improve RV function, thereby preparing it for a better adaptation post-LVAD implantation. Furthermore, meticulous management of patients during the perioperative and immediate postoperative period should facilitate identification of RV failure refractory to medication. When RHF occurs late during chronic LVAD support, this is associated with worse long-term outcomes. Careful monitoring of RV function and characterization of the origination deficit should therefore continue throughout the patient's entire follow-up. Despite the useful information provided by the echocardiogram with respect to RV function, right heart catheterization frequently offers additional support for the assessment and optimization of RV function in LVAD-supported patients. In any patient candidate for LVAD therapy, evaluation and treatment of RV function and failure should be assessed in a multidimensional and multidisciplinary manner.

Pressure-dimension index and left ventricular sphericity index following HeartMate II and HeartMate 3 implantation

AIMS

This study aimed to compare the changes in the left ventricle (LV) and right ventricle (RV) geometry and performance after the implantation of HeartMate II (HMII) and HeartMate 3 (HM3). In addition, we investigated whether the echocardiographic parameters LV sphericity index (LVSI) and the novel pressure-dimension index (PDI) can predict post-operative right ventricular failure (RVF).

METHODS AND RESULTS

Between 2012 and 2020, 46 patients [HMII (n = 22) and HM3 (n = 24)] met the study's criteria and had echocardiography tests pre-operatively, 6 and 12 months post-operatively. The LVSI and PDI were calculated together with the standard LV and RV echocardiographic parameters. The mean follow-up was 24 ± 7 months. In both groups, the LV end-diastolic diameter (LVEDD) significantly decreased 12 months post-operatively compared with the pre-operative values (HMII: 6.4 ± 1.4 cm vs. 5.7 ± 0.9 cm, P = 0.040; HM3: 6.7 ± 1.3 cm vs. 5.5 ± 0.9 cm, P < 0.01, respectively). RV function 12 months post-operatively was better in the HM3 group than in the HMII group, as indicated by a significantly higher RV fractional area change (RVFAC) in the HM3 group than in the HMII group 12 months post-operatively (35 ± 12% vs. 26 ± 16%, P = 0.039), significantly higher tricuspid annular plane systolic excursion (TAPSE) in the HM3 group 12 months post-operatively compared with the HMII group (13.9 ± 1.9 mm vs. 12.0 ± 2.1 mm, P = 0.002), and the tissue Doppler estimated tricuspid annular systolic velocity (TASV) was also significantly higher in the HM3 group 12 months post-operatively compared with the HMII group (11.5 ± 2.7 mm/s vs. 9.9 ± 1.5 mm/s, P = 0.020). The LVSI value was significantly higher 12 months post-operatively in the HMII group than in the HM3 group (1.2 ± 0.4 vs. 0.8 ± 0.2, P = 0.001, respectively), indicating worse geometric changes. The PDI decreased 12 months post-operatively in the HM3-group compared with the baseline (3.4 ± 1.4 mmHg/cm2 vs. 2.0 ± 0.8 mmHg/cm2, P < 0.001). In the univariate and multivariate analyses, only the pre-operative PDI was a predictor of post-operative RVF [odds ratio: 3.84 (95% CI: 1.53-18.16, P = 0.022)]. The area under the curve for pre-operative PDI was 0.912. The 2 year survival was significantly better in the HM3 group (log-rank, P = 0.042).

CONCLUSIONS

The design of HM3 offered better geometrical preservation of the LV and enabled normal PDI values, leading to improved RV function, as indicated by better RVFAC, TAPSE, and TASV values. The use of pre-operative PDI as an additional tool for established risk scores might offer a better pre-operative predictor of RVF.

Risk factors, diagnostic methods and treatment of infection in adult patients undergoing left ventricular assist device implantation: A scoping review

BACKGROUND

Evidence on infection risk factors is scarce, and precise localization of the site of infection and its treatment remain clinically challenging.

OBJECTIVES

This study aimed to map the recommendations for adult patients undergoing left ventricular assist device implantation.

DESIGN

This is a scoping review, registered in the Open Science Framework under DOI10.17605/OSF.IO/Q76B3(https://osf.io/q76b3/).

METHOD

This is a scoping review limited to the period between 2015 and 2022.The results of this scoping review are discussed and presented separately in 3 articles. This second paper synthesizes research evidence on the risk factors, diagnostic methods and treatment of infection in adult patients undergoing left ventricular assist device implantation.

RESULTS

The initial searches identified 771 studies. Sixty-nine patients met the eligibility criteria and were included in the scoping review. Forty-three articles addressing the risk factors, diagnosis and treatment of infection were included to answer the questions of this review.

CONCLUSION

Obesity has been shown to be the most common risk factor for the described process of infection by left ventricular assist devices.18F-fluorodeoxyglucose positron emission tomography showed high sensitivity in detecting cardiac device infection, and labeled leukocyte or gallium citrate-67 scintigraphy showed high specificity for left ventricular assist device infections; therefore, it can help differentiate infection from inflammation, particularly in patients with equivocal fluorodeoxyglucose positron emission tomography. Also, this review brings and discusses the limitations and strengths of diagnostic tests, the knowledge regarding the risk factors for left ventricular assist device infection, the therapeutic heterogeneity, the methodological issues of the studies, and the vast opportunity for future research on left ventricular assist device.

IMPLICATIONS FOR CLINICAL PRACTICE

Ventricular assist device professionals should evaluate risk factors prior to device implantation and periodically.18F-fluorodeoxyglucose positron emission tomography should be considered as diagnostic tool in detecting superficial and deep driveline infections. Early treatment, including chronic suppressive therapy and serial surgical debridement, combined with driveline exteriorization and delayed driveline relocation may constitute a potential therapeutic strategy for deep driveline infections.

Multimodality imaging for the evaluation and management of patients with long-term (durable) left ventricular assist devices

Left ventricular assist devices (LVADs) are gaining increasing importance as therapeutic strategy in advanced heart failure (HF), not only as bridge to recovery or to transplant but also as destination therapy. Even though long-term LVADs are considered a precious resource to expand the treatment options and improve clinical outcome of these patients, these are limited by peri-operative and post-operative complications, such as device-related infections, haemocompatibility-related events, device mis-positioning, and right ventricular failure. For this reason, a precise pre-operative, peri-operative, and post-operative evaluation of these patients is crucial for the selection of LVAD candidates and the management LVAD recipients. The use of different imaging modalities offers important information to complete the study of patients with LVADs in each phase of their assessment, with peculiar advantages/disadvantages, ideal application, and reference parameters for each modality. This clinical consensus statement sought to guide the use of multimodality imaging for the evaluation of patients with advanced HF undergoing LVAD implantation.

Echocardiography-Guided Radiofrequency Ablation for Cardiac Tumors

Background

Patients with cardiac tumors may present challenges for surgical resection due to poor clinical condition. Echocardiography-guided transapical radiofrequency ablation for cardiac tumors (TARFACT) potentially offers a less invasive palliative therapy option.

Objectives

This study aimed to evaluate the safety and efficacy of TARFACT.

Methods

Five patients with cardiac tumors (mucinous liposarcoma, myocardial hypertrophy with inflammatory cell infiltration mass, fibrous tissue tumor hyperplasia, myocardial clear cell sarcoma, and cardiac rhabdomyoma) were included. All patients underwent TARFACT and were assessed with electrocardiogram, echocardiographic imaging, biochemical analysis, and pathological confirmation.

Results

The median follow-up for all patients was 9 (range 4-12) months. Three surviving patients were alive at their last follow-up (9, 12, and 12 months, respectively), whereas 2 patients with late-stage tumors survived 6 months and 13 months after TARFACT, respectively. After TARFACT, all patients showed significant reductions in tumor size: the mean length decreased from 6.7 ± 2.0 cm to 4.7 ± 1.8 cm (P = 0.007); and the mean width decreased from 5.0 ± 2.1 cm to 2.5 ± 0.7 cm (P = 0.041). NYHA functional class also improved: median (IQR) decreased from 3.0 (1.5) to 2.0 (1.0) (P = 0.038), Peak E-wave on echocardiography showed a mean increase from 64.4 ± 15.7 cm/s to 76.6 ± 18.6 cm/s (P = 0.008), and NT-pro BNP levels had a median (IQR) reduction from 115.7 (252.1) pg/mL to 55.0 (121.6) pg/mL (P = 0.043).

Conclusions

TARFACT is a novel palliative treatment option for cardiac tumors, reducing accessible tumors and improving clinical symptoms in a preliminary group of patients. (Cardiac Tumors Interventional [Radio Frequency/Laser Ablation] Therapy [CTIH]; NCT02815553).

Echocardiographic haemodynamic monitoring in the context of HeartMate 3™ therapy: a systematic review

AIMS

While echocardiography remains essential within haemodynamic monitoring of durable mechanical circulatory support, previous echocardiographic guidelines are missing scientific evidence for the novel HeartMate 3™ (HM3) system. Accordingly, this review aims to summarize available echocardiographic evidence including HM3.

METHODS AND RESULTS

This systematic review adhered to the PRISMA 2020 guidelines. Searches were conducted during August 2023 across PubMed, Embase, and Google Scholar using specific echocardiographic terms combined with system identifiers. Study quality was assessed using the Newcastle-Ottawa Scale (NOS) for cohort studies and Critical Appraisal Instrument (PCAI) for cross-sectional studies. Nine studies met the inclusion criteria, of which eight cohort studies and one cross-sectional study. Aortic regurgitation (AR) prevalence at approximately 12 months of support exhibited heterogenicity (33.5% (Δ 33%)) in a limited number of studies (n = 3). Several studies (n = 5) demonstrated an increasing prevalence and severity of AR during HM3 support, generating moderate to high level of evidence. One AR study showed a higher cumulative incidence of death and heart failure (HF) readmission compared with those without significant AR, hazard ratio 3.42 (95% CI 1.48-8.76). A second study showed that a worsening AR group had significantly lower survival-free from HF readmission (59% vs. 89%, P = 0.023) with a hazard ratio of 5.18 (95% CI 1.07-25.0), while a third study did not reveal any differences in cardiac-related hospitalizations in the 12 months follow-up or non-cardiac-related hospitalization. Mitral regurgitation (MR) prevalence at approximately 12 months of support exhibited good consistency 15.0% (Δ 0.8%) in both included studies, which did not reveal any significant pattern of changing prevalence over time. Tricuspid regurgitation (TR) prevalence at approximately 12 months of support exhibited fair consistency 28.5% (Δ 8.3%) in a limited number of studies (n = 2); both studies showed a statistically un-confirmed trend of increased TR prevalence over time. The evidence of general prevalence of right ventricular dysfunction (RVD) was insufficient due to lack of studies.

CONCLUSIONS

There are few methodologically consistent studies with focus on long-term haemodynamic effects. Aortic regurgitation still seems to be a prevalent and potentially significant finding. The available evidence concerning right heart function is limited despite clinical relevance and potential prognostic value. Potential interventricular and haemodynamic interplay are identified as a white field for future research.

Contemporary Role of Positron Emission Tomography (PET) in Endocarditis: A Narrative Review

Endocarditis, a serious infectious disease, remains a diagnostic challenge in contemporary clinical practice. The advent of advanced imaging modalities has contributed significantly to the improved understanding and management of this complex disease. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) imaging has shown remarkable potential in improving the diagnostic accuracy of endocarditis. In the update of the Modified Duke Criteria, in 2023, The International Society for Cardiovascular Infectious Diseases (ISCVID) Working Group recognized specific 18F-FDG PET/CT findings as a major diagnostic criterion, particularly in patient with prosthetic valve endocarditis. The ability of PET to visualize metabolic activity allows for the identification of infective foci and could differentiate between infective and non-infective processes. This review examines the clinical utility of PET in differentiating infective endocarditis from other cardiovascular pathologies, highlighting its sensitivity and specificity in detecting native and prosthetic valve infections, including patients with transcatheter aortic valve implantation (TAVI), cardiac implantable devices (CIEDs), and left ventricular assistance devices (LVAD). Also, practical aspects and indications are illustrated to optimize the quality of imaging and reduce potential false positive results. In conclusion, the current use of PET in endocarditis has become a valuable diagnostic tool; as technological advances continue, PET will play an increasingly important role in the multidisciplinary approach to the management of endocarditis.

Bridge to Life: Current Landscape of Temporary Mechanical Circulatory Support in Heart-Failure-Related Cardiogenic Shock

Acute heart failure (HF) presents a significant mortality burden, necessitating continuous therapeutic advancements. Temporary mechanical circulatory support (MCS) is crucial in managing cardiogenic shock (CS) secondary to acute HF, serving as a bridge to recovery or durable support. Currently, MCS options include the Intra-Aortic Balloon Pump (IABP), TandemHeart (TH), Impella, and Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO), each offering unique benefits and risks tailored to patient-specific factors and clinical scenarios. This review examines the clinical implications of recent advancements in temporary MCS, identifies knowledge gaps, and explores promising avenues for future research and clinical application. Understanding each device's unique attributes is crucial for their efficient implementation in various clinical scenarios, ultimately advancing towards intelligent, personalized support strategies.

Optimization of photon counting CT for cardiac imaging in patients with left ventricular assist devices: An in-depth assessment of metal artifacts

PURPOSE

Photon counting CT (PCCT) holds promise for mitigating metal artifacts and can produce virtual mono-energetic images (VMI), while maintaining temporal resolution, making it a valuable tool for characterizing the heart. This study aimed to evaluate and optimize PCCT for cardiac imaging in patients during left ventricular assistance device (LVAD) therapy by conducting an in-depth objective assessment of metal artifacts and visual grading.

METHODS

Various scan and reconstruction settings were tested on a phantom and further evaluated on a patient acquisition to identify the optimal protocol settings. The phantom comprised an empty thoracic cavity, supplemented with heart and lungs from a cadaveric lamb. The heart was implanted with an LVAD (HeartMate 3) and iodine contrast. Scans were performed on a PCCT (NAEOTOM Alpha, Siemens Healthcare). Metal artifacts were assessed by three objective methods: Hounsfield units (HU)/SD measurements (DiffHU and SDARTIFACT), Fourier analysis (AmplitudeLowFreq), and depicted LVAD volume in the images (BloomVol). Radiologists graded metal artifacts and the diagnostic interpretability in the LVAD lumen, cardiac tissue, lung tissue, and spinal cord using a 5-point rating scale. Regression and correlation analysis were conducted to determine the assessment method most closely associated with acquisition and reconstruction parameters, as well as the objective method demonstrating the highest correlation with visual grading.

RESULTS

Due to blooming artifacts, the LVAD volume fluctuated between 27.0 and 92.7 cm3. This variance was primarily influenced by kVp, kernel, keV, and iMAR (R2 = 0.989). Radiologists favored pacemaker iMAR, 3 mm slice thickness, and T3D keV and kernel Bv56f for minimal metal artifacts in cardiac tissue assessment, and 110 keV and Qr40f for lung tissue interpretation. The model adequacy for DiffHU SDARTIFACT, AmplitueLowFreq, and BloomVol was 0.28, 0.76, 0.29, and 0.99 respectively for phantom data, and 0.95, 0.98, 1.00, and 0.99 for in-vivo data. For in-vivo data, the correlation between visual grading (VGSUM) and DiffHU SDARTIFACT, AmplitueLowFreq, and BloomVol was -0.16, -0.01, -0.48, and -0.40 respectively.

CONCLUSION

We found that optimal scan settings for LVAD imaging involved using 120 kVp and IQ level 80. Employing T3D with pacemaker iMAR, the sharpest allowed vascular kernel (Bv56f), and VMI at 110 keV with kernel Qr40 yields images suitable for cardiac imaging during LVAD-therapy. Volumetric measurements of the LVAD for determination of the extent of blooming artifacts was shown to be the best objective method to assess metal artifacts.

18F-FDG PET/CT and Radiolabeled Leukocyte SPECT/CT Imaging for the Evaluation of Cardiovascular Infection in the Multimodality Context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations From ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multisocietal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multifocal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

Diagnostic Contexts of Echocardiographic Nonapical Window

The long-established utility of multiwindow interrogation in echocardiography (suprasternal notch, right and left sternal border, apex, and subxiphoid) is sometimes not systematically implemented in routine practice. This case series emphasizes the pivotal importance of such practice for the systematic assessment of aortic valve stenosis and in the evaluation of left ventricular outflow tract and the aorta.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

Urgent Spinal Surgery in a Lateral Decubitus on a Patient with a Left Ventricular Assist Device on Full Anticoagulation: A Case Report

This case report aims to demonstrate the feasibility of performing spinal surgery in patients with a left ventricular assist device (LVAD), who are traditionally considered unsuitable candidates due to the need for anticoagulation and the challenges associated with the prone position. A case of a patient with an LVAD undergoing microdiscectomy in the left lateral decubitus position is presented. The procedure was carried out by a specialized interdisciplinary team with appropriate monitoring. The patient underwent the procedure safely, demonstrating that spinal surgery can be performed in patients with LVAD without reversing anticoagulation or resorting to the prone position. This approach mitigates the risk of thrombotic events and hemodynamic instability. This case study suggests that spinal surgery, specifically microdiscectomy, can be safely performed in patients with LVAD using the left lateral decubitus position. This finding has significant implications for patients who are unable to ambulate and therefore struggle to qualify for a heart transplant.

Echocardiographic imaging and ventricular mechanics in pulsatile-flow LVAD pediatric patients: a systematic approach

Echocardiography plays a crucial role in determining the eligibility for left ventricular assist device (LVAD) placement in patients experiencing advanced heart failure (HF) and in monitoring patient care after the implantation procedure. Because of its unique nature, pediatric population and pulsatile-flow LVADs used in pediatrics require specific skills so that pediatric echocardiographers must develop a systematic approach in order to image the patients pre and post LVAD implantation. Therefore, the purpose of this narrative review is to delineate a systematic echocardiographic approach for pediatric patients supported by pulsatile-flow LVADs.

A systematic methodology for epicardial and epiaortic echocardiography in swine research models

Background

Perioperative echocardiography is of paramount importance during cardiac surgery. Nonetheless, in the experimental large-animal setting, it might be challenging obtaining optimal imaging when using conventional imaging acquisition techniques, such as transthoracic and transesophageal screenings. Open-chest surgery allows epicardial echocardiographic assessment with direct contact between probe and heart, thus providing superior quality. Standard protocols regarding the use of epicardial ultrasound in swine for research purposes are lacking.

Methods

Epicardial echocardiography was performed in 10 female German Landrace pigs undergoing cardiac surgery. A structured and comprehensive protocol for epicardial echocardiography was elaborated including apical, ventricular long and short axis, as well as epiaortic planes. All experiments were approved by the local board for animal welfare and conducted in accordance with the German animal protection law (TierSchG) and the ARRIVE guidelines.

Conclusions

Systematic protocols using epicardial echocardiography may serve as an additional tool to assess cardiac dimensions and function in experimental scenarios with swine models.

Multimodality Imaging in Advanced Heart Failure for Diagnosis, Management and Follow-Up: A Comprehensive Review

Advanced heart failure (AHF) presents a complex landscape with challenges spanning diagnosis, management, and patient outcomes. In response, the integration of multimodality imaging techniques has emerged as a pivotal approach. This comprehensive review delves into the profound significance of these imaging strategies within AHF scenarios. Multimodality imaging, encompassing echocardiography, cardiac magnetic resonance imaging (CMR), nuclear imaging and cardiac computed tomography (CCT), stands as a cornerstone in the care of patients with both short- and long-term mechanical support devices. These techniques facilitate precise device selection, placement, and vigilant monitoring, ensuring patient safety and optimal device functionality. In the context of orthotopic cardiac transplant (OTC), the role of multimodality imaging remains indispensable. Echocardiography offers invaluable insights into allograft function and potential complications. Advanced methods, like speckle tracking echocardiography (STE), empower the detection of acute cell rejection. Nuclear imaging, CMR and CCT further enhance diagnostic precision, especially concerning allograft rejection and cardiac allograft vasculopathy. This comprehensive imaging approach goes beyond diagnosis, shaping treatment strategies and risk assessment. By harmonizing diverse imaging modalities, clinicians gain a panoramic understanding of each patient's unique condition, facilitating well-informed decisions. The aim is to highlight the novelty and unique aspects of recently published papers in the field. Thus, this review underscores the irreplaceable role of multimodality imaging in elevating patient outcomes, refining treatment precision, and propelling advancements in the evolving landscape of advanced heart failure management.

Imaging for implementation of heart failure guidelines

The classification of heart failure with implications for pharmacological therapeutic interventions rests on defining ejection fraction (EF) which is an imaging parameter. Imaging can provide diagnostic clues as to aetiology of heart failure; it can also guide and help assess response to treatment. Echocardiography, CMR, cardiac computed tomography, positron emission tomography, and Tc 99 m pyrophosphate scanning provide information about the aetiology of heart failure. Further, echocardiography plays the primary role in the evaluation of LV diastolic function and the estimation of left ventricular (LV) filling pressures both at rest and with exercise during diastolic stress testing. Heart failure guidelines recognize four stages (A, B, C, and D) for heart failure. Cardiac imaging along with risk factors and clinical status is needed for identifying these stages. There are joint societal echocardiographic guidelines by American Society of Echocardiography (ASE) of Echocardiography and European Association of Cardiovascular Imaging that are applicable to the imaging of heart failure patients. There are also separate guidelines for the evaluation of patients being considered for LV assist device implantation and for multimodality imaging of patients with heart failure and preserved EF. Cardiac catheterization is needed in patients whose haemodynamic status is uncertain after clinical and echocardiographic evaluation and to evaluate for coronary artery disease. Myocardial biopsy can identify the presence of myocarditis or specific infiltrative diseases when the findings by non-invasive imaging are not conclusive.

Late Right Heart Failure After Left Ventricular Assist Device Implantation: Contemporary Insights and Future Perspectives

Late right heart failure (RHF) is increasingly recognized in patients with long-term left ventricular assist device (LVAD) support and is associated with decreased survival and increased incidence of adverse events such as gastrointestinal bleeding and stroke. Progression of right ventricular (RV) dysfunction to clinical syndrome of late RHF in patients supported with LVAD is dependent on the severity of pre-existing RV dysfunction, persistent or worsening left- or right-sided valvular heart disease, pulmonary hypertension, inadequate or excessive left ventricular unloading, and/or progression of the underlying cardiac disease. RHF likely represents a continuum of risk with early presentation and progression to late RHF. However, de novo RHF develops in a subset of patients leading to increased diuretic requirement, arrhythmias, renal and hepatic dysfunction, and heart failure hospitalizations. The distinction between isolated late RHF and RHF due to left-sided contributions is lacking in registry studies and should be the focus of future registry data collection. Potential management strategies include optimization of RV preload and afterload, neurohormonal blockade, LVAD speed optimization, and treatment of concomitant valvular disease. In this review, the authors discuss definition, pathophysiology, prevention, and management of late RHF.

Development of the Modern Cardiothoracic Intensive Care Unit and Current Management

The modern cardiothoracic intensive care unit (CTICU) developed as a result of advances in critical care, cardiology, and cardiac surgery. Patients undergoing cardiac surgery today are sicker, frailer, and have more complex cardiac and noncardiac morbidities. CTICU providers need to understand postoperative implications of different surgical procedures, complications that can occur in CTICU patients, resuscitation protocols for cardiac arrest, and diagnostic and therapeutic interventions such as transesophageal echocardiography and mechanical circulatory support. Optimum CTICU care requires a multidisciplinary team with collaboration between cardiac surgeons and critical care physicians with training and experience in the care of CTICU patients.

HFSA Expert Consensus Statement on the Medical Management of Patients on Durable Mechanical Circulatory Support

The medical management of patients supported with durable continuous flow left ventricular assist device (LVAD) support encompasses pharmacologic therapies administered in the preoperative, intraoperative, postoperative and chronic LVAD support stages. As patients live longer on LVAD support, the risks of LVAD-related complications and progression of cardiovascular and other diseases increase. Using existing data from cohort studies, registries, randomized trials and expert opinion, this Heart Failure Society of America Consensus Document on the Medical Management of Patients on Durable Mechanical Circulatory Support offers best practices on the management of patients on durable MCS, focusing on pharmacological therapies administered to patients on continuous flow LVADs. While quality data in the LVAD population are few, the utilization of guideline directed heart failure medical therapies (GDMT) and the importance of blood pressure management, right ventricular preload and afterload optimization, and antiplatelet and anticoagulation regimens are discussed. Recommended pharmacologic regimens used to mitigate or treat common complications encountered during LVAD support, including arrhythmias, vasoplegia, mucocutaneous bleeding, and infectious complications are addressed. Finally, this document touches on important potential pharmacological interactions from anti-depressants, herbal and nutritional supplements of relevance to providers of patients on LVAD support.

Patient-specific, echocardiography compatible flow loop model of aortic valve regurgitation in the setting of a mechanical assist device

Background

Aortic regurgitation (AR) occurs commonly in patients with continuous-flow left ventricular assist devices (LVAD). No gold standard is available to assess AR severity in this setting. Aim of this study was to create a patient-specific model of AR-LVAD with tailored AR flow assessed by Doppler echocardiography.

Methods

An echo-compatible flow loop incorporating a 3D printed left heart of a Heart Mate II (HMII) recipient with known significant AR was created. Forward flow and LVAD flow at different LVAD speed were directly measured and AR regurgitant volume (RegVol) obtained by subtraction. Doppler parameters of AR were simultaneously measured at each LVAD speed.

Results

We reproduced hemodynamics in a LVAD recipient with AR. AR in the model replicated accurately the AR in the index patient by comparable Color Doppler assessment. Forward flow increased from 4.09 to 5.61 L/min with LVAD speed increasing from 8,800 to 11,000 RPM while RegVol increased by 0.5 L/min (2.01 to 2.5 L/min).

Conclusions

Our circulatory flow loop was able to accurately replicate AR severity and flow hemodynamics in an LVAD recipient. This model can be reliably used to study echo parameters and aid clinical management of patients with LVAD.

Myocardial mechanics of percutaneous intramyocardial septal radiofrequency ablation

OBJECTIVE

Echocardiography-guided Percutaneous IntraMyocardial Septal Radiofrequency Ablation (PIMSRA, Liwen procedure) is a novel treatment option for hypertrophic obstructive cardiomyopathy (HOCM). The impact of PIMSRA on myocardial mechanics is unknown.

METHODS

Between October 2016 and June 2019, PIMSRA and 3-dimentional speckle tracking echocardiography were performed in 82 patients. Echocardiographic imaging, qualitative and quantitative clinical assessment were completed at baseline, immediately postprocedure and 1-year follow-up.

RESULTS

There was a significant reduction in the peak left ventricular outflow tract (LVOT) gradients immediately following PIMSRA and at 1-year follow-up (resting gradients: from 83.50 (61.25) to 23.00 (41.75) mm Hg, p<0.001 and 13.50 (21.75) mm Hg, p<0.001, respectively; stress-induced gradients: from 118.25 (96.02) to 47.00 (74.50) mm Hg (1 year), p<0.001). There was an improvement in exercise time on stress echocardiography (p<0.001) and distance by 6 min walk test (p=0.034). Immediately after PIMSRA, there was a significant reduction in radial and circumferential strain in the ablated segments (p<0.001), with no change of longitudinal strain. At 1-year follow-up, the radial and circumferential strain recovered in the ablated segments. Meanwhile, left ventricular regional and global longitudinal strain had improved significantly (p<0.05).

CONCLUSIONS

PIMSRA is an effective treatment for symptomatic HOCM that resulted in a sustained improvement in exercise capacity, a persistent decrease in LVOT gradient, and a measurable increase in myocardial contractile function.

TRIAL REGISTRATION NUMBER

NCT04777188.

Reciprocal interferences of the left ventricular assist device and the aortic valve competence

Patients suffering from end-stage heart failure tend to have high mortality rates. With growing numbers of patients progressing into severe heart failure, the shortage of available donors is a growing concern, with less than 10% of patients undergoing cardiac transplantation (CTx). Fortunately, the use of left ventricular assist devices (LVADs), a variant of mechanical circulatory support has been on the rise in recent years. The expansion of LVADs has led them to be incorporated into a variety of clinical settings, based on the goals of therapy for patients ailing from heart failure. However, with an increase in the use of LVADs, there are a host of complications that arise with it. One such complication is the development and progression of aortic regurgitation (AR) which is noted to adversely influence patient outcomes and compromise pump benefits leading to increased morbidity and mortality. The underlying mechanisms are likely multifactorial and involve the aortic root-aortic valve (AV) complex, as well as the LVAD device, patient, and other factors, all of them alter the physiological mechanics of the heart resulting in AV dysfunction. Thus, it is imperative to screen patients before LVAD implantation for AR, as moderate or greater AR requires a concurrent intervention at the time of LVADs implantation. No current strict guidelines were identified in the literature search on how to actively manage and limit the development and/or progression of AR, due to the limited information. However, some recommendations include medical management by targeting fluid overload and arterial blood pressure, along with adjusting the settings of the LVADs device itself. Surgical interventions are to be considered depending on patient factors, goals of care, and the underlying pathology. These interventions include the closure of the AV, replacement of the valve, and percutaneous approach via percutaneous occluding device or transcatheter aortic valve implantation. In the present review, we describe the interaction between AV and LVAD placement, in terms of patient management and prognosis. Also it is provided a comprehensive echocardiographic strategy for the precise assessment of AV regurgitation severity.

Emerging concepts in heart failure management and treatment: focus on point-of-care ultrasound in cardiogenic shock

Point-of-care ultrasound (POCUS) plays a strategic role in the diagnostic and therapeutic evaluation of critically ill patients and, especially, in those who are haemodynamically unstable. In this context, POCUS allows a more precise identification of the cause, its differential diagnosis, the eventual coexistence with another entity and, finally, guiding of the therapeutic approach. It implies a portable use of ultrasound in acute settings covering different specified protocols, such as echocardiography, vascular, lung or abdominal ultrasound. This article reviews POCUS application in the emergency department or the intensive care unit, focused on severely compromised patients with cardiogenic shock with an emergent bedside assessment. Considering the high mortality rate of this entity, POCUS provides the intensivist/clinician with an appropriate tool for accurate diagnoses and a timely management plan. The authors propose practical algorithms for the diagnosis of patients using POCUS in these settings. This article is part of the Emerging concepts in heart failure management and treatment Special Issue: https://www.drugsincontext.com/special_issues/emerging-concepts-in-heart-failure-management-and-treatment.

Aortic valve disorders and left ventricular assist devices

Aortic valve disorders are important considerations in advanced heart failure patients being evaluated for left ventricular assist devices (LVAD) and those on LVAD support. Aortic insufficiency (AI) can be present prior to LVAD implantation or develop de novo during LVAD support. It is usually a progressive disorder and can lead to impaired LVAD effectiveness and heart failure symptoms. Severe AI is associated with worsening hemodynamics, increased hospitalizations, and decreased survival in LVAD patients. Diagnosis is made with echocardiographic, device assessment, and/or catheterization studies. Standard echocardiographic criteria for AI are insufficient for accurate diagnosis of AI severity. Management of pre-existing AI includes aortic repair or replacement at the time of LVAD implant. Management of de novo AI on LVAD support is challenging with increased risks of repeat surgical intervention, and percutaneous techniques including transcatheter aortic valve replacement are assuming greater importance. In this manuscript, we provide a comprehensive approach to contemporary diagnosis and management of aortic valve disorders in the setting of LVAD therapy.

Transcatheter Aortic Valve Replacement for Left Ventricular Assist Device-Related Aortic Regurgitation: The Michigan Medicine Experience

Background

Aortic regurgitation (AR) is common and detrimental in patients with left ventricular assist devices (LVADs). Off-label use of transcatheter aortic valve replacement (TAVR) has emerged as a potential treatment option. Further data are required regarding the feasibility and outcomes of TAVR to treat AR in LVAD recipients.

Methods

A retrospective review of all patients with LVADs who underwent TAVR for the treatment of AR at a single center was performed. All echocardiograms were independently reviewed to ensure accuracy.

Results

Eleven patients with continuous-flow LVADs underwent TAVR for AR. All patients had moderate or severe AR with New York Heart Association (NYHA) class III and IV symptoms. Implantation of more than 1 valve was required in 4 (36.3%) patients; 1 patient died during the procedure because of valve migration into the left ventricle and 1 patient died in-hospital after TAVR. Of 9 (81.8%) patients discharged alive, 8 (72.7%) were alive at 12 months and all survivors had improvement in AR severity, natriuretic peptide levels, left ventricle end-diastolic diameter, and NYHA class. Five (62.5%) survivors had a large improvement (>20 points) in the Kansas City Cardiomyopathy Questionnaire score at 1 year. One survivor experienced heart failure, requiring hospitalization, within 1 year.

Conclusions

In this single-center series, TAVR for the treatment of AR in patients with LVADs is technically challenging but feasible in select patients and may produce durable improvements in AR severity, functional status, and quality of life.

Left Ventricular Assist Devices: A Primer For the General Cardiologist

Durable implantable left ventricular assist devices (LVADs) have been shown to improve survival and quality of life for patients with stage D heart failure. Even though LVADs remain underused overall, the number of patients with heart failure supported with LVADs is steadily increasing. Therefore, general cardiologists will increasingly encounter these patients. In this review, we provide an overview of the field of durable LVADs. We discuss which patients should be referred for consideration of advanced heart failure therapies. We summarize the basic principles of LVAD care, including medical and surgical considerations. We also discuss the common complications associated with LVAD therapy, including bleeding, infections, thrombotic issues, and neurologic events. Our goal is to provide a primer for the general cardiologist in the recognition of patients who could benefit from LVADs and in the principles of managing patients with LVAD. Our hope is to "demystify" LVADs for the general cardiologist.

Incidental Thrombus Straddling Patent Foramen Ovale Found on Intraoperative Transesophageal Echocardiogram in a Patient With a Ventricular Assist Device

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The hemodynamic changes of surgery demand close monitoring in patients with LVADs.

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During intraoperative TEE, a bubble study may help to diagnose a PFO.

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TEE monitoring is optimal for patients with LVADs undergoing noncardiac procedures.

Update on the Practical Role of Echocardiography in Selection, Implantation, and Management of Patients Requiring Left Ventricular Assist Device Therapy

PURPOSE OF REVIEW

Echocardiography is a valuable tool for management of patients with a left ventricular assist device (LVAD). We present an updated review on the practical applications of the role of echocardiography for pre- and postoperative evaluation of patients selected.

RECENT FINDINGS

The LVAD is a temporary or permanent option for patients with advanced heart failure who are unresponsive to other therapy. Use of the device has its own risks, and implantation remains a complex procedure. Transthoracic and transesophageal echocardiography are useful tools for patient evaluation and monitoring both peri- and postoperatively, as we previously presented. Assessment of left and right ventricular function, complications such as thrombus formation or intracardiac shunting, and valvular disease are all important in this assessment. This also aids in predicting postoperative complications. Placement of the device is confirmed intraoperatively, and subsequent ramp studies are used to determine optimal device settings. Right ventricular (RV) failure is the most common postoperative complication and preoperative evaluation of its function is crucial. Studies suggest that tricuspid annular plane systolic excursion, RV fractional area change, and RV global longitudinal strain are strong predictors of RV failure; LV ejection fraction, size, and end-diastolic diameter are also important markers. Aortic regurgitation and mitral stenosis must always be corrected prior to LVAD placement. However, direct visualization before and after implantation, especially to rule out potential contraindications such as thrombi, cannot be overemphasized. Ramp studies remain an integral part of device optimization and may result in greater myocardial recovery than previously realized.

Role of the mitral valve in left ventricular assist device pathophysiology

Functional mitral regurgitation (MR) in the setting of heart failure results from progressive dilatation of the left ventricle (LV) and mitral annulus. This leads to leaflet tethering with posterior displacement. Contrary to common assumptions, MR often does not resolve with LVAD decompression of the LV alone. The negative impact of significant (moderate-severe) mitral regurgitation in the LVAD setting is becoming better recognized in terms of its harmful effect on right heart function, pulmonary vascular resistance and hospital readmissions. However, controversies remain regarding the threshold for intervention and management. At present, there are no consensus indications for the repair of significant mitral regurgitation at the time of LVAD implantation due to the conflicting data regarding potential adverse effects of MR on clinical outcomes. In this review, we summarize the current understanding of MR pathophysiology in patients supported with LVAD and potential future management strategies.

A multidisciplinary approach for the emergency care of patients with left ventricular assist devices: A practical guide

The use of a left ventricular assist device (LVAD) as a bridge-to-transplantation or destination therapy to support cardiac function in patients with end-stage heart failure (HF) is increasing in all developed countries. However, the expertise needed to implant and manage patients referred for LVAD treatment is limited to a few reference centers, which are often located far from the patient's home. Although patients undergoing LVAD implantation should be permanently referred to the LVAD center for the management and follow-up of the device also after implantation, they would refer to the local healthcare service for routine assistance and urgent health issues related to the device or generic devices. Therefore, every clinician, from a bigger to a smaller center, should be prepared to manage LVAD carriers and the possible risks associated with LVAD management. Particularly, emergency treatment of patients with LVAD differs slightly from conventional emergency protocols and requires specific knowledge and a multidisciplinary approach to avoid ineffective treatment or dangerous consequences. This review aims to provide a standard protocol for managing emergency and urgency in patients with LVAD, elucidating the role of each healthcare professional and emphasizing the importance of collaboration between the emergency department, in-hospital ward, and LVAD reference center, as well as algorithms designed to ensure timely, adequate, and effective treatment to patients with LVAD.