Stress Cardiovascular Magnetic Resonance Imaging for the Detection of Coronary Artery Disease.

Stress cardiovascular magnetic resonance (CMR) imaging has received extensive validation for the assessment of ischemic heart disease. Without ionizing radiation exposure, it offers in-depth information regarding cardiac structure and function, presence and degree of myocardial ischemia and myocardial viability. When compared to other imaging modalities, it has demonstrated excellent sensitivity and specificity in detecting functionally relevant coronary artery stenosis, as well as strong prognostic value in clinical risk stratification. The current scientific data support a greater expansion of stress CMR. This review investigates the current stress CMR techniques and protocols, as well as its relevance in diagnosis and prognosis of coronary artery disease.

Multiparametric identification of subclinical atrial fibrillation after an embolic stroke of undetermined source.

BACKGROUND: Subclinical atrial fibrillation (SCAF) may represent a cause of embolic stroke of undetermined source (ESUS) and its detection has important implications for secondary prevention with anticoagulation. Indications to implantable cardiac monitors (ICM) include SCAF detection. The aims of this study were to (1) evaluate the frequency of ICM-detected SCAF; (2) determine predictors of SCAF; and (3) identify patients who would benefit most from ICM implantation. METHODS: Between February 2017 and November 2020, all consecutive patients referred for ICM implantation after a diagnosis of ESUS and without previous history of atrial fibrillation or atrial flutter were included in this study. SCAF was diagnosed if the ICM electrogram demonstrated an episode of irregularly irregular rhythm without distinct P waves lasting > 2 min. RESULTS: We enrolled 109 patients (age 66, SD = 13 years; 36% females). During a median follow-up of 19.2 (IQR 11.0-27.5) months, SCAF episodes were detected in 36 (33%) patients. Only abnormal P wave terminal force in lead V1, left atrial end-systolic indexed volume > 34 ml/m2, and BMI > 25 kg/m2 were independently associated with an increased risk of SCAF (HR 2.44, 95% CI 1.14-5.21, p = 0.021; HR 2.39, 95% CI 1.11-5.13, p = 0.026; and HR 2.64, 95% CI 1.06-6.49, p = 0.036 respectively). The ROC curve showed that the presence of all three parameters had the best accuracy (74%) to predict SCAF detection (sensitivity 39%, specificity 91%). CONCLUSION: A multiparametric evaluation has the best accuracy to predict SCAF in ESUS patients and may help identifying those who would benefit most from ICM.

Coronary sinus and great cardiac vein electroanatomic mapping predicts the activation delay of the coronary sinus branches.

BACKGROUND: Implantation of left ventricular (LV) lead in segments with delayed electrical activation may improve response to cardiac resynchronization therapy (CRT). The search for the latest LV electrical delay (LVED) site can be time-consuming. OBJECTIVE: To assess if electrical mapping of coronary sinus (CS) and magna cardiac vein can help to identify the latest activated CS branch. METHODS: We retrospectively evaluated 48 consecutive patients who underwent electroanatomic mapping system-guided (EAMS)-CRT device implantation with ≥2 mapped CS branches. The activation mapping of the CS and relative branches were performed using an insulated guide wire. LVED was defined as the interval between the beginning of the QRS complex on the surface electrocardiogram and the local electrogram and expressed in milliseconds (ms). RESULTS: Thirty-two (67%) patients showed left bundle branch block (LBBB) and 16 (33%) non-LBBB electrocardiographic patterns. A total of 116 CS branches (mean, 2.4/patient; range, 2-5) were mapped. In the left oblique view, most patients (N = 39, 81%) showed the latest CS-LVED in lateral segments while nine (19%) showed the latest CS-LVED in anterior or posterior segments. Specifically, 94% of patients with LBBB showed the latest CS-LVED in lateral segments while CS activation among non-LBBB patients was heterogeneous. In all patients, the CS branch that demonstrated the highest LVED originated from the latest activated segment of the CS. CONCLUSION: Electrical mapping of CS allows identifying the latest activated branches. This finding may contribute to simplify CRT device implantation compared to activation mapping of all the branches.

Reproducibility of pulmonary vein isolation guided by the ablation index: 1-year outcome of the AIR registry.

BACKGROUND: Ablation index (AI) is a new lesion quality marker that has been demonstrated to allow a high single-procedure arrhythmia-free survival in single-center studies. This prospective, multi-center study was designed to evaluate the reproducibility of pulmonary vein (PV) isolation guided by the AI. METHODS: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV isolation and were divided in four study groups according to operator's preference in choosing the ablation catheter (a contact force (ST) or contact force surround flow (STSF) catheter) and the AI setting (330-450 or 380-500 at anterior wall or posterior wall, respectively). RESULTS: At 12 months a high rate of freedom from AF recurrences was observed in patients with both paroxysmal and persistent AF (91% vs 83.3%; P = .039). There was no difference in the rate of AF recurrence among the four study groups (4.5% in group ST330-450, 12.2% in group ST 380-500, 14.9% in group STSF330-450, 9.4% in group STSF380-500; P = .083). Recurrence was also similar between patients treated with a ST (8%) or STSF catheter (12.1%; P = .2), and within patients targeting an AI settings of 330 to 450 (10.9%) or 380 to 500 (10.3%; P = .64). In patients with paroxysmal AF, there was no difference (P = .12) in the 1-year freedom from AF recurrence among 14 operators that performed ≥10 ablation procedure. CONCLUSIONS: An ablation protocol respecting strict criteria for contiguity and quality lesion resulted in high rate of 1-year freedom from AF recurrence, irrespective of the ablation catheters, AI settings, and operator.

Real-world comparison of in-hospital Reveal LINQ insertable cardiac monitor insertion inside and outside of the cardiac catheterization or electrophysiology laboratory.

BACKGROUND: Traditionally, insertable cardiac monitor (ICM) procedures have been performed in the cardiac catheterization (CATH) or electrophysiology (EP) laboratory. The introduction of the miniaturized Reveal LINQ ICM has led to simplified and less invasive procedures, affording hospitals flexibility in planning where these procedures occur without compromising patient safety or outcomes. METHODS: The present analysis of the ongoing, prospective, observational, multicenter Reveal LINQ Registry sought to provide real-world feasibility and safety data regarding the ICM procedure performed in the CATH/EP lab or operating room and to compare it with insertions performed outside of these traditional hospital settings. Patients included had at least a 30-day period after the procedure to account for any adverse events. RESULTS: We analyzed 1222 patients (58.1% male, age 61.0 ± 17.1 years) enrolled at 18 centers in the US, 17 centers in Middle East/Asia, and 15 centers in Europe. Patients were categorized into 2 cohorts according to the location of the procedure: in-lab (CATH lab, EP lab, or operating room) (n = 820, 67.1%) and out-of-lab (n = 402, 32.9%). Several differences were observed regarding baseline and procedure characteristics. However, no significant differences in the occurrence of procedure-related adverse events (AEs) were found; of 19 ICM/procedure-related AEs reported in 17 patients (1.4%), 11 occurred in the in-lab group (1.3%) and 6 in the out-of-lab group (1.5%) (P = .80). CONCLUSIONS: This real-world analysis demonstrates the feasibility of performing Reveal LINQ ICM insertion procedures outside of the traditional hospital settings without increasing the risk of infection or other adverse events.

Reproducibility of acute pulmonary vein isolation guided by the ablation index.

BACKGROUND: Atrial fibrillation (AF) ablation outcome is still operator dependent. Ablation Index (AI) is a new lesion quality marker that has been demonstrated to allow acute durable pulmonary vein (PV) isolation followed by a high single-procedure arrhythmia-free survival. This prospective, multicenter study was designed to evaluate the reproducibility of acute PV isolation guided by the AI. METHODS: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV encircling and were divided in four study groups according to operator preference in choosing the ablation catheter (a contact force [ST] or contact force surround flow [STSF] catheter) and the AI setting (330 at posterior and 450 at anterior wall or 380 at posterior and 500 at anterior wall). Radiofrequency was delivered targeting interlesion distance ≤6 mm. RESULTS: The rate of first-pass PV isolation (ST330 90 ± 16%, ST380 87 ± 19%, STSF330 90 ± 17%, STSF380 91 ± 15%, P = .585) was similar among the four study groups, whereas procedure (ST330 129 ± 44 minutes, ST380 144 ± 44 minutes, STSF330 120 ± 72 minutes, STSF380 125 ± 73 minutes, P < .001) and fluoroscopy time (ST330 542 ± 285 seconds, ST380 540 ± 416 seconds, STSF330 257 ± 356 seconds, STSF380 379 ± 454 seconds, P < 0.001) significantly differed. The difference in the rate of first-pass isolation was not statistical different (P = .06) among the 12 operators that performed at least 15 procedures. CONCLUSIONS: An ablation protocol respecting strict criteria for contiguity and quality lesion results in high and comparable rate of acute PV isolation among operator performing ablation with different catheters, AI settings, procedure, and fluoroscopy times.

Clinical impact, safety, and accuracy of the remotely monitored implantable loop recorder Medtronic Reveal LINQTM.

Aims: Implantable loop recorders (ILR) are indicated in a variety of clinical situations when extended cardiac rhythm monitoring is needed. We aimed to assess the clinical impact, safety, and accuracy of the new Medtronic Reveal LINQTM ILR that can be inserted outside the electrophysiology (EP) laboratory and remotely monitored. Methods and results: All 154 consecutive patients (100 males, 63 ± 15 year-old) who received the Reveal LINQTM ILR during the period July 2014-June 2016 were enrolled. The device was implanted in a procedure room and all patients where provided with the MyCareLinkTM remote monitoring system. Data were reviewed every working day via the Carelink® web system by a specialist nurse who, in case of significant events, consulted an electrophysiologist. During a mean follow-up of 12.1 (6.7-18.4) months (range 2-24 months), a diagnosis was made in 99 (64%) patients and in 60 (39%) ≥1 therapeutic interventions were established following recording of arrhythmias. In 26 of these 60 patients, remote monitoring prompted therapeutic interventions following asymptomatic arrhythmic events 3.8 months before the next theoretical scheduled in-office data download. False bradycardia detection for undersensing occurred in 44 (29%) patients and false tachycardia detection for oversensing in 4 (3%). One patient experienced skin erosion requiring explantation and none suffered from infection. Conclusion: The remote monitoring feature of the Reveal LINQTM allowed earlier diagnosis of asymptomatic but serious arrhythmias in a significant proportion of patients. Implantation of the device outside the EP laboratory appeared safe. However, R-wave undersensing and consequent false recognition of bradyarrhythmias remains a clinically important technical issue.

Contiguity Between Ablation Lesions and Strict Catheter Stability Settings Assessed by VISITAGTM Module Improve Clinical Outcomes of Paroxysmal Atrial Fibrillation Ablation　- Results From the VISITALY Study.

BACKGROUND: Our aim was to evaluate the clinical outcome of paroxysmal atrial fibrillation (AF) ablation with contact force technology, using an automated lesion tagging system (VISITAGTM module) with strict criteria of catheter stability.Methods and Results:We enrolled 200 consecutive patients who underwent pulmonary vein isolation (PVI) in 11 centers and were followed up for 12 months. The stability setting was within 3 mm for ≥10 s and for ≥15 s in 47% and 53% of patients, respectively. A mean of 67.2±21.9 VISITAGs was acquired. Freedom from atrial tachyarrhythmias at follow-up was 77.5% (155/200), and the contiguity between lesions was associated with a higher chronic success rate (96% vs. 77.1%; log-rank P=0.036). Radiofrequency (RF), fluoroscopy times, and recurrence rates at the 12-month follow-up were significantly lower than in a comparison group of 80 patients without VISITAGTM module (42.7±14.5 vs. 50.9±23.6 min; P=0.032; 11.6±7.8 vs. 18.4±12.8 min; P=0.003 and 22.5% vs. 41.2%; P=0.02). Two major complications (1 cardiac tamponade and 1 minor stroke) were observed only in the control group. CONCLUSIONS: Paroxysmal AF ablation with contact force technology and strict criteria of stability using the VISITAG module was a safe procedure, associated with an improvement in efficiency and a reduction of atrial tachyarrhythmia recurrence at the 12-month follow-up compared with manual annotation. Contiguity between lesions seemed to enhance effectiveness outcomes.

A Cost-Effective Analysis of Systematically Using Mapping Systems During Catheter Ablation Procedures in Children and Teenagers.

The aim of this study is to evaluate the cost-effectiveness of an extended use of 3D non-fluoroscopic mapping systems (NMSs) during paediatric catheter ablation (CA) in an adult EP Lab. This study includes 58 consecutive patients (aged between 8 and 18) who underwent CA from March 2005 to February 2015. We compare the fluoroscopy data of two groups: group I, patients who underwent CA from 2005 to 2008 using only fluoroscopy, and group II, patients who underwent CA from 2008 to 2015 performed also using NMSs. Two cost-effectiveness analyses were carried out: the first method was based on the alpha value (AV), and the second one was based on the value of a statistical life (VSL). For both methods, a children's correction factor was also considered. The reduction cost estimated from all these methods was compared to the real additional cost of using NMSs. The use of an NMS during a CA procedure has led to an effective dose reduction (ΔE) of 2.8 milli-Sievert. All presented methods are based on parameters with a wide range of values. The use of an NMS, applying directly AV values or VSL values, is not cost-effective for most countries. Only considering the children's correction factor, the CA procedure using an NMS seems to be cost-effective. The cost-effectiveness of a systematic use of NMSs during CA procedures in children and teenagers remains a challenging task. A positive result depends on which value of AV or VSL is considered and if the children's correction factor is applied or not.

Three-Dimensional Electroanatomic Mapping System-Enhanced Cardiac Resynchronization Therapy Device Implantation: Results From a Multicenter Registry.

INTRODUCTION: Cardiac resynchronization therapy (CRT) device implantation guided by an electroanatomic mapping system (EAMS) is an emerging technique that may reduce fluoroscopy and angiography use and provide information on coronary sinus (CS) electrical activation. We evaluated the outcome of the EAMS-guided CRT implantation technique in a multicenter registry. METHODS: During the period 2011-2014 we enrolled 125 patients (80% males, age 74 [71-77] years) who underwent CRT implantation by using the EnSite system to create geometric models of the patient's cardiac chambers, build activation mapping of the CS, and guide leads positioning. Two hundred and fifty patients undergoing traditional CRT implantation served as controls. Success and complication rates, fluoroscopy and total procedure times in the overall study population and according to center experience were collected. Centers that performed ≥10 were defined as highly experienced. RESULTS: Left ventricular lead implantation was successful in 122 (98%) cases and 242 (97%) controls (P = 0.76). Median fluoroscopy time was 4.1 (0.3-10.4) minutes in cases versus 16 (11-26) minutes in controls (P < 0.001). Coronary sinus angiography was performed in 33 (26%) cases and 208 (83%) controls (P < 0.001). Complications occurred in 5 (4%) cases and 17 (7%) controls (P = 0.28). Median fluoroscopy time (median 11 minutes vs. 3 minutes, P < 0.001) and CS angiography rate (55% vs. 21%, P < 0.001) were significantly higher in low experienced centers, while success rate and complications rate were similar. CONCLUSIONS: EAMS-guided CRT implantation proved safe and effective in both high- and low-experienced centers and allowed to reduce fluoroscopy use by ≈75% and angiography rate by ≈70%.

Near zerO fluoroscopic exPosure during catheter ablAtion of supRavenTricular arrhYthmias: the NO-PARTY multicentre randomized trial.

AIMS: Aim of this study was to compare a minimally fluoroscopic radiofrequency catheter ablation with conventional fluoroscopy-guided ablation for supraventricular tachycardias (SVTs) in terms of ionizing radiation exposure for patient and operator and to estimate patients' lifetime attributable risks associated with such exposure. METHODS AND RESULTS: We performed a prospective, multicentre, randomized controlled trial in six electrophysiology (EP) laboratories in Italy. A total of 262 patients undergoing EP studies for SVT were randomized to perform a minimally fluoroscopic approach (MFA) procedure with the EnSiteTMNavXTM navigation system or a conventional approach (ConvA) procedure. The MFA was associated with a significant reduction in patients' radiation dose (0 mSv, iqr 0-0.08 vs. 8.87 mSv, iqr 3.67-22.01; P < 0.00001), total fluoroscopy time (0 s, iqr 0-12 vs. 859 s, iqr 545-1346; P < 0.00001), and operator radiation dose (1.55 vs. 25.33 µS per procedure; P < 0.001). In the MFA group, X-ray was not used at all in 72% (96/134) of cases. The acute success and complication rates were not different between the two groups (P = ns). The reduction in patients' exposure shows a 96% reduction in the estimated risks of cancer incidence and mortality and an important reduction in estimated years of life lost and years of life affected. Based on economic considerations, the benefits of MFA for patients and professionals are likely to justify its additional costs. CONCLUSION: This is the first multicentre randomized trial showing that a MFA in the ablation of SVTs dramatically reduces patients' exposure, risks of cancer incidence and mortality, and years of life affected and lost, keeping safety and efficacy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01132274.

The Benefit of a General, Systematic Use of Mapping Systems During Electrophysiological Procedures in Children and Teenagers: The Experience of an Adult EP Laboratory.

Standard imaging during electrophysiological procedures (EPs) uses fluoroscopy. The aim of this study was to evaluate the feasibility, efficacy, safety and effect of an extended use of non-fluoroscopic mapping systems (NMSs) for imaging during paediatric EPs in an adult EP laboratory focusing on the amount of X-ray exposure. This study is a retrospective analysis that includes consecutive young patients (83 pts, aged between 8 and 18) who underwent EPs from March 2005 to February 2015. We compare the fluoroscopy data of two groups of pts: Group I, pts who underwent EPs from 2005 to 2008 using only fluoroscopy and Group II, pts who underwent EPs from 2008 to 2015 performed also using NMSs. The use of an NMS resulted in reduced fluoroscopy time in Group II {median value 0.1 min (95 % CI [0.00-1.07])} compared to Group I {median value 3.55 min (95 % CI [1.93-7.83]) (MW test, P < 0.05)}. There was a complementary reduction in the total X-ray exposure from 2.53 Gy cm(2) (95 % CI [1.51-4.66]) in Group I to 0.05 Gy cm(2) in Group II (95 % CI [0.00-1.22]) (MW test, P < 0.05). Regarding ablation procedures, the median effective dose decreased from 3.04 mSv (95 % CI [1.22-6.89]) to 0.25 mSv (95 % CI [0.00-0.60]) (MW test, P < 0.05). The use of an NMS dramatically reduces fluoroscopy time and total X-ray exposure during EPs in children and teenagers in an adult EP laboratory. In our experience, this reduction is mainly related to the systematic day-to-day use of NMSs.

Electroanatomic mapping and late gadolinium enhancement MRI in a genetic model of arrhythmogenic atrial cardiomyopathy.

INTRODUCTION: Although atrial arrhythmias may have genetic causes, very few data are available on evaluation of the arrhythmic substrate in genetic atrial diseases in humans. In this study, we evaluate the nature and evolution of the atrial arrhythmic substrate in a genetic atrial cardiomyopathy. METHODS AND RESULTS: Repeated electroanatomic mapping and tomographic evaluations were used to investigate the evolving arrhythmic substrate in 5 patients with isolated arrhythmogenic atrial cardiomyopathy, caused by Natriuretic Peptide Precursor A (NPPA) gene mutation. Atrial fibrosis was assessed using late gadolinium enhancement magnetic resonance imaging (LGE-MRI). The substrate of atrial tachycardia (AT) and atrial fibrillation (AF) was biatrial dilatation with patchy areas of low voltage and atrial wall scarring (in the right atrium: 68.5% ± 6.0% and 22.2% ± 10.2%, respectively). The evolution of the arrhythmic patterns to sinus node disease with atrial standstill (AS) was associated with giant atria with extensive low voltage and atrial scarring areas (in the right atrium: 99.5% ± 0.7% and 57.5% ± 33.2%, respectively). LGE-MRI-proven biatrial fibrosis (Utah stage IV) was associated with AS. Atrial conduction was slow and heterogeneous, with lines of conduction blocks. The progressive extension and spatial distribution of the scarring/fibrosis were strictly associated with the different types of arrhythmias. CONCLUSION: The evolution of the amount and distribution of atrial scarring/fibrosis constitutes the structural substrate for the different types of atrial arrhythmias in a pure genetic model of arrhythmogenic atrial cardiomyopathy.

Low incidence of permanent complications during catheter ablation for atrial fibrillation using open-irrigated catheters: a multicentre registry.

AIMS: Despite catheter ablation (CA) has become an accepted treatment option for symptomatic, drug-resistant atrial fibrillation (AF), the safety of this procedure continues to be cause for concern. The aim of the present study was to assess the incidence of complications with permanent sequelae of CA for AF using open-irrigated catheters in a contemporary, unselected population of consecutive patients. METHODS AND RESULTS: From 1 January 2011 to 31 December 2011, data from 2167 consecutive patients who underwent CA for AF using an open-irrigated catheter in 29 Italian centres were collected. All the complications occurring to the patient from admission to the 30th post-procedural day were recorded. No procedure-related death was observed. Complications occurred in 81 patients (3.7%): 46 patients (2.1%) suffered vascular access complications; 13 patients (0.6%) cardiac tamponade, successfully drained in all the cases; six patients (0.3%) arterial thromboembolism (four transient ischaemic attack and two ischaemic strokes); five (0.2%) patients conservatively treated pericardial effusion; three patients (0.1%) phrenic nerve paralysis; three patients (0.1%) pericarditis; three patients (0.1%) haemothorax, and two patients (0.1%) other isolated adverse events. At multivariate analysis, only female sex [odds ratio (OR) 2.5, confidence interval (CI): 1.5-3.7, P < 001] and the operator experience (OR 0.5, CI: 0.4-0.7, P < 001) related to the complications. Only five (0.2%) patients developed permanent sequelae from their complications. CONCLUSION: Catheter ablation for AF with the use of open-irrigated catheters is currently affected by a very low rate of complications leading to permanent sequelae.

Identification of left atrial fibrosis with a late-enhancement MR sequence (LE-MR): preliminary results.

PURPOSE: This study was done to identify left atrial fibrosis in a group of consecutive patients with atrial fibrillation (AF) candidate for percutaneous radiofrequency catheter ablation (RFCA) by using a late-enhancement magnetic resonance (LE-MR) sequence, and to validate the technique by comparison with electroanatomical mapping (EAM). MATERIALS AND METHODS: We enrolled 37 patients (29 males; mean age, 61 years) candidate for percutaneous RFCA of AF, who were studied with LE-MR and EAM. To identify left AF we used a three-dimensional LE sequence with cardiac gating and respiratory navigator. The EAM study involved the acquisition of 200 points in the left atrium (LA). The LA was divided into seven segments (pulmonary vein antra, floor, anterior wall, posterior wall-roof). Two blinded radiologists assessed the presence of fibrosis (area of hyperintense signal), reaching a consensus in discordant cases. Inter-observer variability was also evaluated to estimate the reproducibility of the method. We analysed the anatomical agreement between the results obtained with LE-MR imaging and EAM. RESULTS: Five patients were excluded because of to poor image quality. As for the other 32 patients, inter-observer agreement was good [Cohen's kappa κ = 0.72 with 95 % confidence interval (CI) of 0.55, 0.89]. In the classification of LA segments affected by fibrosis, LE-MR had a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 66 % (95 % CI 53.7 %, 77.2 %); 87 % (95 % CI 80.9 %, 91.9 %); 69 % (95 % CI 56.5 %, 80.1 %); 85.5 % (95 % CI 79.1 %, 90.6 %) and 81 % (95 % CU 75.1 %, 85.7 %). CONCLUSIONS: Despite the small size of the sample studied, the LE-MR sequence proved more useful for excluding the presence of AF than for confirming its existence. Identification of AF prior to RFCA is paramount to select those patients who are truly amenable to the ablation procedure, which is expensive and not entirely free of risks.

The role of computational methods in cardiovascular medicine: a narrative review.

Background and Objective: Computational models of the cardiovascular system allow for a detailed and quantitative investigation of both physiological and pathological conditions, thanks to their ability to combine clinical-possibly patient-specific-data with physical knowledge of the processes underlying the heart function. These models have been increasingly employed in clinical practice to understand pathological mechanisms and their progression, design medical devices, support clinicians in improving therapies. Hinging upon a long-year experience in cardiovascular modeling, we have recently constructed a computational multi-physics and multi-scale integrated model of the heart for the investigation of its physiological function, the analysis of pathological conditions, and to support clinicians in both diagnosis and treatment planning. This narrative review aims to systematically discuss the role that such model had in addressing specific clinical questions, and how further impact of computational models on clinical practice are envisaged. Methods: We developed computational models of the physical processes encompassed by the heart function (electrophysiology, electrical activation, force generation, mechanics, blood flow dynamics, valve dynamics, myocardial perfusion) and of their inherently strong coupling. To solve the equations of such models, we devised advanced numerical methods, implemented in a flexible and highly efficient software library. We also developed computational procedures for clinical data post-processing-like the reconstruction of the heart geometry and motion from diagnostic images-and for their integration into computational models. Key Content and Findings: Our integrated computational model of the heart function provides non-invasive measures of indicators characterizing the heart function and dysfunctions, and sheds light on its underlying processes and their coupling. Moreover, thanks to the close collaboration with several clinical partners, we addressed specific clinical questions on pathological conditions, such as arrhythmias, ventricular dyssynchrony, hypertrophic cardiomyopathy, degeneration of prosthetic valves, and the way coronavirus disease 2019 (COVID-19) infection may affect the cardiac function. In multiple cases, we were also able to provide quantitative indications for treatment. Conclusions: Computational models provide a quantitative and detailed tool to support clinicians in patient care, which can enhance the assessment of cardiac diseases, the prediction of the development of pathological conditions, and the planning of treatments and follow-up tests.

Incidental and anticipated arrhythmic diagnoses in patients with an implantable cardiac monitor.

AIMS: In this study, we investigated a cohort of unselected patients with various indications for an implantable cardiac monitor (ICM). Our main objectives were to determine the incidence of arrhythmic diagnoses, both anticipated and incidental in relation to the ICM indication, and to assess their clinical relevance. METHODS: We examined remote monitoring transmissions from patients with an ICM at four Italian sites to identify occurrences of cardiac arrhythmias. Concurrently, we collected data on medical actions taken in response to arrhythmic findings. RESULTS: The study included 119 patients, with a median follow-up period of 371 days. ICM indications were syncope/presyncope (46.2%), atrial fibrillation management (31.1%), and cryptogenic stroke (22.7%). In the atrial fibrillation management group, atrial fibrillation was the most common finding, with an incidence of 36% [95% confidence interval (CI) 22-55%] at 18 months. Rates of atrial fibrillation were not significantly different between patients with cryptogenic stroke and syncope/presyncope [17% (95% CI 7-40%) vs. 8% (95% CI 3-19%), P  = 0.229].For patients with cryptogenic stroke, the incidence of asystole and bradyarrhythmias at 18 months was 23% (95% CI 11-45%) and 42% (95% CI 24-65%), respectively, similar to estimates obtained for patients implanted for syncope/presyncope ( P  = 0.277 vs. P  = 0.836).Overall, 30 patients (25.2%) required medical intervention following ICM-detected arrhythmias, predominantly involving atrial fibrillation ablation (10.9%) and medication therapy changes (10.1%). CONCLUSION: In a real-life population with heterogeneous insertion indications, approximately 25% of patients received ICM-guided medical interventions within a short timeframe, including treatments for incidental findings. Common incidental arrhythmic diagnoses were bradyarrhythmias in patients with cryptogenic stroke and atrial fibrillation in patients with unexplained syncope.

Strategic reprogramming of implantable cardiac monitors reduces the false-positive remote alert burden in a nurse-led service.

AIMS: Implantable cardiac monitors (ICMs) can generate false-positive (FP) alerts. Although these devices have an extended programmability, there are no recommendations on their optimization to reduce not-relevant activations.We tested a strategic programming optimization guide based on the type of FP and investigated the safety and feasibility of the nurse-led insertion of ICMs with a long-sensing vector. METHODS AND RESULTS: Consecutive patients implanted by trained nurses with long-sensing vector ICM were enrolled in a 1-month observational stage (Phase A). Patients who had ≥10 FP episodes underwent ICM reprogramming based on the predefined guide and were followed for an additional month (Phase B). A total of 78 patients had successful ICM insertion by nurses with a mean R wave amplitude of 0.96 ± 0.43 mV and an 86% P wave visibility. Only one patient reported a significant device-related issue, and nurse-delivered ICM was generally well accepted by the patients. During Phase A, 11 patients (14%) generated most of FP (3,627/3,849; 94%) and underwent ICM reprogramming. In the following month (Phase B), five patients (45%) were free from FP and six (55%) transmitted 57 FP alerts (98% reduction compared with Phase A). The median number of FP per patient was significantly reduced after reprogramming [195 (interquartile range, 50-311) vs. one (0-10), P = 0.0002]. CONCLUSION: A strategic reprogramming of ICM in those patients with a high FP alert burden reduces the volume of erroneous activations with potential benefits for the remote monitoring service. No concerns were raised regarding nurse-led insertion of ICMs with a long-sensing vector.

Daily and automatic remote monitoring of implantable cardiac monitors: A descriptive analysis of transmitted episodes.

BACKGROUND: Remote Monitoring (RM) is recognized for its ability to enhance the clinical management of patients with implantable cardiac monitor (ICM). This study aims to provide a comprehensive description of the arrhythmic episodes transmitted by a daily and automatic RM system from a cohort of ICM patients. METHODS: The study retrospectively analyzed daily transmissions from consecutive patients who had been implanted with a long-sensing vector ICM (BIOMONITOR III/IIIm) at four sites. All transmitted arrhythmic recordings were evaluated to determine whether they were true positive episodes or false positives (FP). RESULTS: A total of 14,136 episodes were transmitted from 119 patients (74.8% male, median age 62 years old) during a median follow-up of 371 days. The rate of arrhythmic episodes was 14.2 per patient-year (interquartile range: 1.8-126), with 97 patients (81.5%) experiencing at least one ICM activation. Fifty-five percent of episodes were identified as FP, and 67 patients (56.3%) had at least one inappropriate activation. The FP rate was 1.4 per patient-year (0-40). The best per-episode predictive positive values were observed for bradycardia and atrial fibrillation (0.595 and 0.553, respectively). Notably, the implementation of an algorithm designed to minimize false detections significantly reduced the prevalence of atrial fibrillation FP episodes (17.6% vs. 43.5%, p = 0.008). CONCLUSION: Daily and automatic RM appears to be a reliable tool for the comprehensive remote management of ICM patients. However, the number of arrhythmic episodes requiring review is high, and further improvements are needed to reduce FP and facilitate accurate interpretation of transmissions.

A Nurse-Led Model of Care with Telemonitoring to Manage Patients with Heart Failure in Primary Health Care: A Mixed-Method Feasibility Study.

Purpose: To determine whether a nurse-led care model with telemonitoring in primary care for patients with stable heart failure and their caregivers is feasible and acceptable. Patients and Methods: A mixed-methods feasibility study was conducted. Patients with stable heart failure and their caregivers were consecutively enrolled from March 2021 to April 2022. Participants were managed by nurses in a community health center through education and monitoring with a mobile app. The outcomes were feasibility outcomes, self-care outcomes, and qualitative acceptability and satisfaction. Quantitative and qualitative outcomes were linked to understanding how the model of care might benefit patients. Results: Twenty-six patients and nine of their caregivers were enrolled. Ten participants used the mobile app. Nineteen patients and eight caregivers were interviewed. Participants who improved their self-care appreciated the help in finding coping strategies, being close to the clinic, and feeling cared for. Participants with fewer improvements in self-care perceived the model of care as useless and were far from the centre. Participants decided to use the app mainly for usefulness prevision, and most of them were satisfied. Conclusion: The model of care was not successful in recruiting patients, and adjustments are needed to improve the recruitment strategy and to engage people who perceive the model of care as not useful or unable to use the app.