Arrhythmias in Patients with Cardiac Amyloidosis: A Comprehensive Review on Clinical Management and Devices.

Cardiac amyloidosis (CA) is a rare but potentially life-threatening disease in which misfolded proteins accumulate in the cardiac wall tissue. Heart rhythm disorders in CA, including supraventricular arrhythmias, conduction system disturbances, or ventricular arrhythmias, play a major role in CA morbidity and mortality, and thus require supplementary management. Among them, AF is the most frequent arrhythmia during CA hospitalizations and is associated with significantly higher mortality, while ventricular arrhythmias are also common and are usually associated with poor prognosis. Early diagnosis of potential arrythmias could be performed through ECG, Holter monitoring, and/or electrophysiology study. Clinical management of these patients is quite significant, and it usually includes initiation of amiodarone and/or digoxin in patients with AF, potential electrical cardioversion, or ablation in specific patients with indication, as well as initiation of anticoagulants in all patients, independent of AF and CHADS-VASc score, for potential intracardiac thrombus. Moreover, identification of patients with conduction disorders that could benefit from prophylactic pacemaker implantation and/or CRT as well as identification of patients with life-threatening ventricular arrythmias that could benefit from ICD could both increase the survival rates of these patients and improve their quality of life.

Invasive and Non-Invasive Diagnostic Pathways in the Diagnosis of Cardiac Amyloidosis.

The appropriate diagnosis and subtyping of cardiac amyloidosis (CA) is frequently missed or delayed due to its vague presentation, clinical overlapping, and diagnostic pitfalls. Recent developments in both invasive and non-invasive diagnostic techniques have significantly changed the diagnostic approach of CA. With the present review, we aim to summarize the current diagnostic approach of CA and to underline the indications of tissue biopsy, either surrogate site or myocardial. The most important factor for timely diagnosis is increased clinical suspicion, especially in certain clinical scenarios. Appropriate imaging with echocardiography or cardiac magnetic resonance (CMR) can provide significant evidence for the diagnosis of CA. Importantly, all patients should undergo monoclonal proteins assessment, with these results significantly determining the steps to follow. A negative monoclonal protein assessment will lead to a non-invasive algorithm which, in combination with positive cardiac scintigraphy, can establish the diagnosis of ATTR-CA. The latter is the only clinical scenario in which the diagnosis can be established without the need of biopsy. However, if the imaging results are negative but the clinical suspicion remains high, a myocardial biopsy should be performed. In the case of the presence of monoclonal protein, an invasive algorithm follows, first by surrogate site sampling and then by myocardial biopsy if the results are inconclusive or prompt diagnosis is needed. The role of endomyocardial biopsy, even though limited by current advances in other techniques, is highly valuable in selected patients and is the only method to reliably establish a diagnosis in challenging cases.

Analysis of heart retransplantation outcomes in the new donor heart allocation system.

Cardiac graft failure may require repeat heart transplantation (HTx). Outcomes of patients that undergo repeat HTx have not been well described. We compared patients that received repeat HTx with patients that received initial HTx by inquiring the United Network for Organ Sharing (UNOS) database between 2015 and 2021. The primary endpoint was all-cause mortality, while the role of baseline characteristics was also investigated. Patients were stratified according to whether they received initial HTx (n = 19,727, 97%) or repeat HTx (n = 578, 3%). Among the study population, 10,860 (53.5%) patients received a HTx using the old UNOS allocation system, whereas 9445 (46.5%) patients received a HTx after the implementation of the new UNOS donor allocation system in October 2018. In this sub-group of HTx recipients in the new allocation system era, the adjusted 1-year survival of repeat HTx patients remained lower than that of initial HTx patients (hazard ratio (HR): 1.19; 95% confidence interval (CI): 1.15, 3.18; p = 0.013). When we compared the 1-year survival of repeat HTx patients before and after the implementation of the new allocation system, the adjusted 1-year survival was similar between groups (HR: 1.14; 95% CI: 0.71, 1.84; p = 0.591). The unadjusted risk of 30-day mortality was not significantly different in the new vs old allocation system. Mortality associated with repeat HTx remained higher than initial HTx but the new donor allocation system implementation did not affect outcomes.

Non-LGE Cardiac Magnetic Resonance Imaging in Patients with Cardiac Amyloidosis.

Cardiac involvement is the leading cause of death in patients with cardiac amyloidosis. Early recognition is crucial as it can significantly change the course of the disease. Until now, the imaging modality of choice for diagnosing cardiac amyloidosis has been cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement (LGE). LGE-CMR in patients with cardiac amyloidosis reveals characteristic LGE patterns that lead to a diagnosis while also correlating well with disease prognosis. However, LGE-CMR has numerous drawbacks that the newer CMR modality, T1 mapping, aims to improve. T1 mapping can be further subdivided into native T1 mapping, which does not require the use of contrast, and ECV measurement, which requires the use of contrast. Numerous T1 mapping techniques have been developed, each one with its own advantages and disadvantages when it comes to procedure difficulty and image quality. A literature review to identify relevant published articles was performed by two authors. This review aimed to present the value of T1 mapping in diagnosing cardiac amyloidosis, quantifying the amyloid burden, and evaluating the prognosis of patients with amyloidosis with cardiac involvement.

Trends, risk factors, and outcomes of post-operative stroke after heart transplantation: an analysis of the UNOS database.

BACKGROUND: Post-operative stroke increases morbidity and mortality after cardiac surgery. Data on characteristics and outcomes of stroke after heart transplantation (HTx) are limited. METHODS AND RESULTS: We conducted a retrospective analysis of the United Network for Organ Sharing (UNOS) database from 2009 to 2020 to identify adults who developed stroke after orthotropic HTx. Heart transplant recipients were divided according to the presence or absence of post-operative stroke. The primary endpoint was all-cause mortality. A total of 25 015 HT recipients were analysed, including 719 (2.9%) patients who suffered a post-operative stroke. The stroke rates increased from 2.1% in 2009 to 3.7% in 2019, and the risk of stroke was higher after the implantation of the new allocation system [odds ratio 1.29, 95% confidence intervals (CI) 1.06-1.56, P = 0.01]. HTx recipients with post-operative stroke were older (P = 0.008), with higher rates of prior cerebrovascular accident (CVA) (P = 0.004), prior cardiac surgery (P < 0.001), longer waitlist time (P = 0.04), higher rates of extracorporeal membrane oxygenation (ECMO) support (P < 0.001), left ventricular assist devices (LVADs) (P < 0.001), mechanical ventilation (P = 0.003), and longer ischaemic time (P < 0.001). After multivariable adjustment for recipient and donor characteristics, age, prior cardiac surgery, CVA, support with LVAD, ECMO, ischaemic time, and mechanical ventilation at the time of HTx were independent predictors of post-operative stroke. Stroke was associated with increased risk of 30 day and all-cause mortality (hazard ratio 1.49, 95% CI 1.12-1.99, P = 0.007). CONCLUSIONS: Post-operative stroke after HTx is infrequent but associated with higher mortality. Redo sternotomy, LVAD, and ECMO support at HTx are among the risk factors identified.