Fabrizio Tundo

Feasibility of combined unipolar and bipolar voltage maps to improve sensitivity of endomyocardial biopsy

Background—Endomyocardial biopsy (EMB) has a low sensitivity. Electroanatomic voltage mapping (EVM) is effective in guiding EMB thanks to its ability in identifying and locating low-voltage regions. The analysis of unipolar EVM can correlate with epicardial pathological involvement. We evaluated the unipolar EVM in EMB areas to determine whether it can increase EMB sensitivity in diagnosing epicardial diseases. Methods and Results—We performed endocardial bipolar EVM-guided EMBs in 29 patients and we analyzed unipolar EVM at withdrawal sites. Eighty myocardial samples were collected (mean, 2.8±0.9; median, 3 fragments per patient) and 60 were suitable for histological analysis. Ten specimens (17%) were collected from an area with discordant normal bipolar/low-voltage unipolar EVM and they were diagnostic or suggestive for arrhythmogenic right ventricular dysplasia/cardiomyopathy in 6 patients, for myocarditis and sarcoidosis in 1 patient each. Six samples (10%) were collected from an area with discordant low-voltage bipolar/normal unipolar EVM and they showed nonspecific features. The sensitivity of unipolar EVMs for a diagnostic biopsy finding EMB was significantly higher compared with bipolar EVMs analyzed according to samples (P<0.01) and patients (P=0.008). The specificity of unipolar EMB was better than bipolar EMB when analyzed for all samples (P=0.0014) but the difference did not reach statistical significance when analyzed by patient (P=0.083). The diagnostic yield was 63.3% for the bipolar and 83.3% for the unipolar EVM. Conclusions—These findings suggest that use of a combined bipolar/unipolar map may be able to improve the diagnostic yield of endomyocardial ventricular biopsy.

C-reactive protein but not atrial dysfunction predicts recurrences of atrial fibrillation after cardioversion in patients with preserved left ventricular function.

Objectives Maintenance of sinus rhythm after cardioversion of atrial fibrillation is a major clinical challenge also in patients with preserved left ventricular function. Subclinical inflammation and atrial strain have been recognized as important contributors to atrial fibrillation onset and perpetuation. Aim of the study was to compare the predictive role of C-reactive protein (CRP) and indices of atrial dysfunction in relation to subacute arrhythmic recurrence rate in patients with persistent atrial fibrillation and normal left ventricular ejection fraction (LVEF). Methods We studied 53 patients with a mean LVEF of 58.7 ± 6%. Left atrial diameter and area, left atrial auricle emptying velocity, N-terminal pro-b-type natriuretic peptide (NT-proBNP) and CRP levels were determined few hours before electrical cardioversion. NT-proBNP and CRP levels were also measured 1 h and 3 weeks after cardioversion. Results Subacute atrial fibrillation recurrences were documented in 18 (33.9%) patients. Whereas none of the parameters reflecting atrial dysfunction predicted arrhythmic outcome, higher CRP levels (>3.0 mg/l) were significantly associated with atrial fibrillation recurrences [odds ratio (OR): 1.6; 95% confidence interval (CI): 1.4–2.5; P = 0.031]. No changes in CRP levels were evident after cardioversion independently of underlying rhythm. On the contrary, NT-proBNP levels, which were correlated with left atrial auricle emptying velocity, significantly decreased only in patients who maintained sinus rhythm (from 638 ± 329 to 295 ± 261 pg/ml; P < 0.001). Conclusion The present study demonstrates that in patients with persistent atrial fibrillation and preserved LVEF, CRP level is an independent predictor of atrial fibrillation subacute recurrence rate, whereas none of the indices of atrial dysfunction is associated with arrhythmic outcome. NT-proBNP levels reflect, instead, the hemodynamic alterations secondary to arrhythmia presence.

Prognostic Benefit of Cardiac Magnetic Resonance Over Transthoracic Echocardiography for the Assessment of Ischemic and Nonischemic Dilated Cardiomyopathy Patients Referred for the Evaluation of Primary Prevention Implantable Cardioverter-Defibrillator Therapy.

Background—The aim of this study was to determine the prognostic benefit of cardiac magnetic resonance (CMR) over transthoracic echocardiography (TTE) in ischemic cardiomyopathy and nonischemic dilated cardiomyopathy patients evaluated for primary prevention implantable cardioverter–defibrillator therapy. Methods and Results—We enrolled 409 consecutive ischemic and dilated cardiomyopathy patients (mean age: 64±12 years; 331 men). All patients underwent TTE and CMR, and left ventricle end-diastolic volume, left ventricle end-systolic volume, and left ventricle ejection fraction (LVEF) were evaluated. In addition, late gadolinium enhancement was also assessed. All patients were followed up for major adverse cardiac events (MACE) defined as a composite end point of long runs of nonsustained ventricular tachycardia, sustained ventricular tachycardia, aborted sudden cardiac death, or sudden cardiac death. The median follow-up was 545 days. CMR showed higher left ventricle end-diastolic volume (mean difference: 43±22.5 mL), higher left ventricle end-systolic volume (mean difference: 34±20.5 mL), and lower LVEF (mean difference: −4.9±10%) as compared to TTE (P<0.01). MACE occurred in 103 (25%) patients. Patients experiencing MACE showed higher left ventricle end-diastolic volume, higher left ventricle end-systolic volume, and lower LVEF with both imaging modalities and higher late gadolinium enhancement per-patient prevalence as compared to patients without MACE. At multivariable analysis, CMR-LVEF ⩽35% (hazard ratio=2.18 [1.3–3.8]) and the presence of late gadolinium enhancement (hazard ratio=2.2 [1.4–3.6]) were independently associated with MACE (P<0.01). A model based on CMR-LVEF ⩽35% or CMR-LVEF ⩽35% plus late gadolinium enhancement detection showed a higher performance in the prediction of MACE as compared to TTE-LVEF resulting in net reclassification improvement of 0.468 (95% confidence interval, 0.283–0.654; P<0.001) and 0.413 (95% confidence interval, 0.23–0.63; P<0.001), respectively. Conclusions—CMR provides additional prognostic stratification as compared to TTE, which may have direct impact on the indication of implantable cardioverter–defibrillator implantation.

High-density substrate-guided ventricular tachycardia ablation: Role of activation mapping in an attempt to improve procedural effectiveness

BACKGROUND Advanced techniques of electroanatomical mapping efficiently guide ventricular tachycardia (VT) ablation strategies; in this context, the adjunctive value of combining activation mapping (AMap) to improve accuracy has not been elucidated. OBJECTIVE To investigate whether conventional AMap further contributes to the identification of critical sites of VT reentry and whether this translates into a more effective ablation outcome in a cohort of patients undergoing VT ablation. METHODS We prospectively enrolled 126 patients (mean age 65.3 ± 10.5 years; left ventricular ejection fraction 33.3% ± 7.2%) with ischemic (n = 89) or idiopathic (n = 37) dilated cardiomyopathy undergoing endocardial (n = 105) or endo-epicardial (n = 21) electroanatomical mapping and ablation. A substrate-guided strategy targeting surrogate markers of reentry was accomplished in all patients, but the feasibility and efficacy of AMap was preliminarily assessed for all induced VTs focusing on early VT suppression obtained during radiofrequency delivery. VT-free survival was assessed by ICD interrogation. RESULTS AMap successfully guided ablation in 62 of 104 (59.6%) patients with inducible VT(s). At 1 year, 6 of 126 (4.8%) patients died; VT recurred in 28 of 126 (22.2%) patients. No significant difference in VT recurrence rate was observed between patients in whom AMap proved effective versus those in whom substrate-guided ablation was not corroborated by AMap (16 of 62 [25.8%] vs 12 of 64 [18.8%]; log-rank test, P = .3). CONCLUSIONS Our findings support the efficacy of a substrate-guided strategy targeting specific markers of arrhythmogenicity identified during sinus rhythm. AMap proves highly efficient acutely but does not improve overall VT-free survival, suggesting that in patients with advanced cardiac disease, life-threatening arrhythmias can be successfully treated by ablation in sinus rhythm, thus limiting procedural risks.

Comparison between First- and Second-Generation Cryoballoon for Paroxysmal Atrial Fibrillation Ablation

Introduction. Cryoballoon (CB) ablation has emerged as a novel treatment for pulmonary vein isolation (PVI) for patients with paroxysmal atrial fibrillation (PAF). The second-generation Arctic Front Advance (ADV) was redesigned with technical modifications aiming at procedural and outcome improvements. We aimed to compare the efficacy of the two different technologies over a long-term follow-up. Methods. A total of 120 patients with PAF were enrolled. Sixty patients underwent PVI using the first-generation CB and 60 patients with the ADV catheter. All patients were evaluated over a follow-up period of 2 years. Results. There were no significant differences between the two groups of patients. Procedures performed with the first-generation CB showed longer fluoroscopy time (36.3 ± 16.8 versus 14.2 ± 13.5 min, resp.; p = 0.00016) and longer procedure times as well (153.1 ± 32 versus 102 ± 24.8 min, resp.; p = 0.019). The overall long-term success was significantly different between the two groups (68.3 versus 86.7%, resp.; p = 0.017). No differences were found in the lesion areas of left and right PV between the two groups (resp., p = 0.61 and 0.57). There were no significant differences in procedural-related complications. Conclusion. The ADV catheter compared to the first-generation balloon allows obtaining a significantly higher success rate after a single PVI procedure during the long-term follow-up. Fluoroscopy and procedural times were significantly shortened using the ADV catheter.

Radiofrequency Catheter Ablation of Life-Threatening Ventricular Arrhythmias Caused by Left Ventricular Metastatic Infiltration

Metastases to the cardiac ventricles are rare and, unfortunately, often follow a rapidly fatal course.1,2 Occasionally, they cause symptomatic ventricular arrhythmias (VAs) for which limited therapeutic options exist, such as antiarrhythmic drugs, whereas the use of catheter ablation, to our knowledge, has never been reported to date. We present the case of a 27-year-old man with a metastatic tumor in the left ventricle and intractable malignant VAs. In February 2009, the patient had been diagnosed with a gluteal sarcoma and initially treated with combined chemotherapy (including anthracyclines) and radiation. Since December 2009, a mild reduction in left ventricular ejection fraction (45%) was detected, and since January 2010, frequent monomorphic premature ventricular contractions (PVCs) and nonsustained ventricular tachycardias (VTs) were documented. Treatment with amiodarone proved helpful, and no life-threatening VAs could be induced on standard electrophysiological study.3 Since April 2010, however, the patient suffered from multiple drug-refractory episodes of sustained VT and ventricular fibrillation, requiring several direct current shocks (Figure 1). His left ventricular ejection fraction had remained stable. Electrical storm resulted in immediate hemodynamic instability and dramatically affected his quality of life. The patient was referred to our institution, where multiple antiarrhythmic drug combinations were tested, both orally and intravenously, allowing a relative stabilization of cardiac rhythm. Cardiac MRI showed a T2-hyperintense, weakly gadolinium-enhanced area at the basis of the anterior papillary muscle, compatible with metastatic infiltration (Figure 2, online-only Data Supplement Movie 1). An oncology consultation hypothesized a life expectancy of <6 months. After about 2 weeks, the recurrence of multiple episodes of VT and ventricular fibrillation required intensive care treatment with deep sedation and assisted ventilation, but still VAs could not be controlled. Thus, a repeat electrophysiological evaluation and radiofrequency …

Electroanatomical mapping systems and intracardiac echo integration for guided endomyocardial biopsy

ABSTRACT Introduction: During the past years, endomyocardial biopsy (EMB) has gradually spread into clinical practice. However, the role of EMB in the diagnosis and treatment of cardiovascular diseases remains a controversial issue, especially in the setting of unexplained ventricular arrhythmias. Areas covered: This review describes the methodology of EMB guided by combined use of three-dimensional electroanatomical mapping systems and intracardiac echo and summarizes the classical, fluoroscopy-guided EMB technique. Finally, the personal experience acquired with the ‘electrophysiologist-made’ integration methodology has been reported. Expert commentary: Since EMB has been considered in the setting of arrhythmogenic cardiomyopathy, myocarditis, cardiac sarcoidosis, drug toxicity, and/or other diseases causing malignant ventricular arrhythmias, the electrophysiologists have started to perform firsthand biopsy. The electrophysiologists introduced the use of electroanatomical mapping systems and intracardiac echo. This new methodology improved significantly biopsy diagnostic yield and allowed to reduce complications.

X‐Ray Exposure in Cardiac Electrophysiology: A Retrospective Analysis in 8150 Patients Over 7 Years of Activity in a Modern, Large‐Volume Laboratory

Background Only a few studies have systematically evaluated fluoroscopy data of electrophysiological and device implantation procedures. Aims of this study were to quantify ionizing radiation exposure for electrophysiological/device implantation procedures in a large series of patients and to analyze the x‐ray exposure trend over years and radiation exposure in patients undergoing atrial fibrillation ablation considering different technical aspects. Methods and Results We performed a retrospective analysis of all electrophysiological/device implantation procedures performed during the past 7 years in a modern, large‐volume laboratory. We reported complete fluoroscopy data on 8150 electrophysiological/device implantation procedures (6095 electrophysiological and 2055 device implantation procedures); for each type of procedure, effective dose and lifetime attributable risk of cancer incidence and mortality were calculated. Over the 7‐year period, we observed a significant trend reduction in fluoroscopy time, dose area product, and effective dose for all electrophysiological procedures (P<0.001) and a not statistically significant trend reduction for device implantation procedures. Analyzing 2416 atrial fibrillation ablations, we observed a significant variability of fluoroscopy time, dose area product and effective dose among 7 different experienced operators (P<0.0001) and a significant reduction of fluoroscopy use over time (P<0.0001) for all of them. Considering atrial fibrillation ablation techniques, fluoroscopy time was not different (P = 0.74) for radiofrequency catheter ablation in comparison with cryoablation, though cryoablation was still associated with higher dose area product and effective dose values (P<0.001). Conclusions Electrophysiological procedures involve a nonnegligible x‐ray use, leading to an increased risk of malignancy. Awareness of radiation‐related risk, together with technological advances, can successfully optimize fluoroscopy use.

Rescue leadless pacemaker implantation in a pacemaker-dependent patient with congenital heart disease and no alternative routes for pacing

Congenital heart disease patients are considered a unique group of patients regarding their high risk of conduction abnormalities , whether de novo or surgically induced , and the challenges in both implantation and management of device related complications. We present a case of a pacemaker-dependent patient with congenital heart disease who experienced complications of both previous epicardial and transvenous pacing which rendered her a non-suitable candidate of both routes.

Elevaciones de la troponina I cardiaca tras la cirugía torácica. Incidencia y correlaciones con las características clínicas basales, la proteína C reactiva y los parámetros perioperatorios

Resumen Introduccion y objetivos La incidencia real de las elevaciones de la troponina I cardiaca tras la cirugia toracica y su correlacion con otros parametros clinicos no esta plenamente definida. El objetivo de este estudio fue evaluar la frecuencia de las elevaciones postoperatorias de la troponina I cardiaca despues de cirugia pulmonar o pleural por sospecha de cancer e investigar las correlaciones con los perfiles clinicos basales, con la proteina C reactiva y los parametros perioperatorios. Metodos Se registro a 50 pacientes consecutivos y se midieron los siguientes parametros en cada paciente: variables clinicas basales y concentracion de la proteina C reactiva, concentracion de troponina I cardiaca en los dias 1, 3 y 5 del postoperatorio, electrocardiograma, presion arterial, y frecuencia cardiaca diarias desde el dia de la operacion hasta el dia 5 del postoperatorio. Resultados Se produjeron elevaciones postoperatorias de la troponina I cardiaca en el 20% de los pacientes y estas estaban significativamente asociadas con los antecedentes de coronariopatia o mas de 2 factores de riesgo coronario (el 80 frente al 32,5%; p = 0,011), los antecedentes de tratamiento antiagregante plaquetario cronico (el 50 frente al 17,5%; p = 0,046), la neumonectomia comparada con los procedimientos menos invasivos (el 40 frente al 10%; p = 0,041), la pericardiotomia (el 30 frente al 2,5%; p = 0,022) y las modificaciones transitorias del segmento ST en el electrocardiograma perioperatorio (el 60 frente al 20%; p = 0,02). No se observo correlacion significativa entre las elevaciones de la troponina I cardiaca y la proteina C reactiva basal. Conclusiones Las elevaciones de la troponina I cardiaca despues de la cirugia toracica son frecuentes y estan asociadas con marcadores clinicos de coronariopatia, procedimientos quirurgicos extensos y cambios isquemicos en el electrocardiograma perioperatorio.