Effect of cryothermic and radiofrequency Cox-Maze IV ablation on atrial size and function assessed by 2D and 3D echocardiography, a randomized trial. To freeze or to burn.

BACKGROUND: Atrial linear scars in Cox-Maze IV procedures are achieved using Cryothermy (Cryo) or radiofrequency (RF) techniques. The subsequent postoperative left atrial (LA) reverse remodelling is unclear. We used 2- and 3-dimensional echocardiography (2-3DE) to compare the impact of Cryo and RF procedures on LA size and function 1 year after Cox-maze IV ablation concomitant with Mitral valve (MV) surgery. METHODS: Seventy-two patients with MV disease and AF were randomized to Cryo (n = 35) or RF (n = 37) ablation. Another 33 patients were enroled without ablation (NoMaze). All patients underwent an echocardiogram the day before and 1 year after surgery. The LA function was assessed on 2D strain by speckle tracking and 3DE. RESULTS: Forty-two ablated patients recovered sinus rhythm (SR) 1 year after surgery. They had comparable left and right systolic ventricular function, LA volume index (LAVI), and 2D reservoir strain before surgery. At follow-up, the 3DE extracted reservoir and booster function were higher after RF (37 ± 10% vs. 26 ± 6%; p < 0.001) than Cryo ablation (18 ± 9 vs. 7 ± 4%; p < 0.001), while passive conduit function was comparable between groups (24 ± 11 vs. 20 ± 8%; p = 0.17). The extent of LAVI reduction depended on the duration of AF preoperatively. CONCLUSIONS: SR restoration after MV surgery and maze results in LA size reduction irrespective of the energy source used. Compared to RF, the extension of ablation area produced by Cryo implies a structural LA remodelling affecting LA systolic function.

Long-Term Electrocardiographic and Echocardiographic Progression of Arrhythmogenic Right Ventricular Cardiomyopathy and Their Correlation With Ventricular Tachyarrhythmias.

BACKGROUND: Prior studies of structural and electrocardiographic changes in arrhythmogenic right ventricular (RV) cardiomyopathy and their role in predicting ventricular arrhythmias (ventricular tachycardia) have shown conflicting results. METHODS: We reviewed 405 ECGs, 315 transthoracic echocardiographies, and 441 implantable cardioverter defibrillator interrogations in 64 arrhythmogenic RV cardiomyopathy patients (56% men, mean age [SD], 44.2 [14.6] years) over a mean follow-up of 10 (range, 2.3-19) years. Generalized estimating equations were used to identify the association between ECG abnormalities, clinical variables, and transthoracic echocardiographic measurements (>mild degree of tricuspid regurgitation, RV outflow tract diameter in parasternal long axis and short axis, RV end-diastolic area, fractional area change). RESULTS: There was a 4.65 (95% CI, 0.51%-8.8%) increase in RV end-diastolic area, a 3.75 (95% CI, 1.17%-6.34%) decrease in fractional area change, and 1.9 (95% CI, 1.3-2.8) higher odds (odds ratio) of RV wall motion abnormality with every 5-year increase in age after patients' first transthoracic echocardiography. >Mild tricuspid regurgitation was an independent predictor of RV enlargement and dysfunction (hazard ratio of >10% drop in fractional area change from baseline [95% CI], 3.51 [1.77-6.95] and hazard ratio of >10% increase in RV end-diastolic area from baseline [95% CI], 4.90 [2.52-9.52]). Patients with implantable cardioverter defibrillator were more likely to develop >mild tricuspid regurgitation and larger structural and functional disease progression. More pronounced increase in RV end-diastolic area was translated into higher rates of any ventricular tachycardia. Inferior T-wave inversions and sum of R waves (mm) in V1 to V3 were predictors of RV enlargement and dysfunction with the former also predicting risk of any ventricular tachycardia. CONCLUSIONS: Arrhythmogenic RV cardiomyopathy is a progressive disease. Tricuspid regurgitation is an independent predictor of structural disease progression, which may be exacerbated by use of a transvenous implantable cardioverter defibrillator lead.

Atrial arrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy: Prevalence, echocardiographic predictors, and treatment.

INTRODUCTION: The clinical role of atrial arrhythmias (AA) in arrhythmogenic right ventricular cardiomyopathy (ARVC) and the echocardiographic variables that predict them are not well defined. We describe the prevalence, types, echocardiographic predictors, and management of AA in patients with ARVC. METHODS: We retrospectively evaluated medical records of 117 patients with definite ARVC (2010 Task Force Criteria) from two tertiary care centers. We identified those patients with sustained AA (>30 seconds), including atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT). We collected demographic, genetic, and clinical data. The median follow-up was 3.4 years (interquartile range = 2.0-5.7). RESULTS: Total 26 patients (22%) had one or more types of AA: AF (n = 19), AFL (n = 9), and AT (n = 8). We performed genetic testing on 84 patients with ARVC (71.8%). Two patients with AA (8%) had peripheral emboli, and one patient (4%) suffered inappropriate implantable cardioverter-defibrillator shock. We performed catheter ablation of AA in eight patients (31%), with no procedural complications. Right atrial area and left atrial volume index were independently associated with increased odds of AA; odds ratio (OR), 1.1 (95% confidence interval [CI]:1.02-1.16) (P = .01) and OR, 1.1 (95% CI:1.03-1.15) (P = .003), respectively. An increase in tricuspid annular plane peak systolic excursion was independently associated with reduced odds; OR, 0.3 (95% CI: 0.1-0.94) (P = .003). CONCLUSIONS: Atrial arrhythmias (AA) are common in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Inappropriate shocks and systemic emboli may be associated with AA. Atrial size and right ventricular dysfunction may help identify patients with ARVC at increased odds of AA.

Right ventricular systolic function and mechanical dispersion identify patients with arrhythmogenic right ventricular cardiomyopathy.

PURPOSE: To assess right ventricular (RV) regional and global systolic function using feature tracking (FT) in patients with a definite diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) and to investigate if changes in strain amplitude and mechanical dispersion indicate a propensity for arrhythmia. MATERIALS AND METHODS: Twenty-seven patients fulfilling Task Force Criteria for ARVC and 24 healthy volunteers underwent MR at 1·5 Tesla. Steady-state free precession cine of long-axis slices and a short-axis stack of the RV was acquired. Segmental longitudinal systolic strain amplitude and time-to-peak (TTP) strain were measured in the four- and two-chamber views of the RV. RESULTS: Compared to controls, patients with ARVC had lower RV ejection fraction (RVEF), (53% vs 57%, P = 0·012) and lower longitudinal strain amplitude in the RV free wall (-20·6 vs -26·3%, P = 0·014) and in the basal part of the RV (-22·8 vs -31·7%, P<0·001). Mechanical dispersion, defined as the standard deviation (SD) of TTP of RV segments, was larger in patients with ARVC (48 ms [21-74] vs 35 ms [13-66 ms], P = 0·02). Patients with ventricular tachycardia (VT) or non-sustained VT had lower RVEF (46% vs 55%, P = 0·008), but did not have significantly lower RV strain amplitude (-19·5% vs 21·0%, P = 0·073) and no signs of mechanical dispersion (49 ms vs 48 ms, P = 0·861) compared to patients without arrhythmia. CONCLUSION: ARVC patients had lower longitudinal absolute strain amplitude in basal RV segments and increased mechanical dispersion compared to healthy volunteers, but the presence of mechanical dispersion was not predictive of ventricular arrhythmia.

Cox-maze IV cryoablation and postoperative heart failure in mitral valve surgery patients.

OBJECTIVE: The indications for and the risk and benefit of concomitant surgical ablation for atrial fibrillation (AF) have not been fully delineated. Our aim was to survey whether the Cox-maze IV procedure is associated with postoperative heart failure (PHF) or other adverse short-term outcomes after mitral valve surgery (MVS). DESIGN: Consecutive patients with AF undergoing MVS with (n = 50) or without (n = 66) concomitant Cox-maze IV cryoablation were analysed regarding perioperative data and one-year mortality. RESULTS: The patients in the Maze group were younger, were in lower NYHA classes, had better right ventricular function and had lower pulmonary artery pressure. The Maze group had 30 min longer median cross-clamp time (CCT) and 50% had PHF compared with 33% in the No-maze group, p = 0.09. Two patients in the No-maze group died within one year of surgery. Congestive heart failure (OR 4.3 [CI 95%: 1.8-10], p < 0.0001) and CCT (OR 1.03 [CI 95%: 1.01-1.04], p = 0.001) were associated with PHF. CONCLUSION: The current data cannot exclude that concomitant cryoablation increases the risk for PHF, possibly by increasing the cross clamp time.