Matthias Koopmann

Higher Degree of Left Atrial Structural Remodeling in Patients with Atrial Fibrillation and Left Ventricular Systolic Dysfunction

Catheter ablation significantly improves the left ventricular (LV) function in patients with atrial fibrillation (AF) and LV systolic dysfunction. In this study, we compared the degree of left atrial structural remodeling (LA‐SRM) in patients with normal versus reduced LV ejection fraction (LVEF). We also studied the impact of LA‐SRM on LVEF improvement in patients undergoing ablation of AF.

Relationship between left atrial tissue structural remodelling detected using late gadolinium enhancement MRI and left ventricular hypertrophy in patients with atrial fibrillation

AIMS Therapeutic effectiveness of ablation of atrial fibrillation (AF) is related to cardiovascular comorbidities. We studied the relationship between left ventricular hypertrophy (LVH) and left atrial tissue structural remodelling (LA-SRM), in patients presenting for AF ablation. METHODS AND RESULTS We identified 404 AF patients who received a late gadolinium enhancement magnetic resonance imaging (LGE-MRI) prior to catheter ablation. Left ventricular hypertrophy was defined as LV mass index >116 g/m(2) in men and >104 g/m(2) in women. One hundred and twenty-two patients were classified as the LVH group and 282 as the non-LVH group. We stratified patients into four stages based on their degree of LA-SRM (minimal, <5% fibrosis; mild, >5-20%; moderate, >20-35%; and extensive, >35%). All patients underwent catheter ablation with pulmonary vein isolation and posterior wall and septal debulking. The procedural outcome was monitored over a 1-year follow-up period. The mean LA-SRM was significantly higher in patients with LVH (19.4 ± 13.2%) than in non-LVH patients (15.3 ± 9.8%; P< 0.01). Patients with LVH generally had extensive LA-SRM (moderate and extensive stages; 38.5% of LVH group) as compared with non-LVH patients (23.1% of non-LVH group; P < 0.01). A Cox regression analysis showed that patients with LVH also had significantly higher AF recurrence rates than non-LVH patients (43.2 vs. 28%; P = 0.008) during the 1-year follow-up period post-ablation. CONCLUSION Patients with LVH tend to have a significantly greater degree of LA-SRM, when compared with patients without LVH. Moreover, LA-SRM is a predictor for procedural success in patients undergoing AF ablation procedure.

The effect of fat pad modification during ablation of atrial fibrillation: late gadolinium enhancement MRI analysis.

Magnetic resonance imaging (MRI) can visualize locations of both the ablation scar on the left atrium (LA) after atrial fibrillation (AF) ablation and epicardial fat pads (FPs) containing ganglionated plexi (GP).

Improvement in Estimated Glomerular Filtration Rate in Patients with Chronic Kidney Disease Undergoing Catheter Ablation for Atrial Fibrillation

Chronic kidney disease (CKD) and atrial fibrillation (AF) often coexist. We studied the association of CKD with atrial fibrosis and the effect of AF ablation on kidney function.

The degree of left atrial structural remodeling impacts left ventricular ejection fraction in patients with atrial fibrillation

OBJECTIVES The extent of left atrial (LA) wall structural remodeling (fibrosis) detected by late gadolinium enhancement-magnetic resonance imaging (LGE-MRI) is correlated with advanced atrial fibrillation (AF). The concomitant occurrence of AF and left ventricular (LV) dysfunction is not uncommon. We studied the effect of LA fibrosis, a confounder of both AF and LV dysfunction, on LV ejection fraction (EF). STUDY DESIGN For the analysis, we identified and included 384 patients from our retrospective AF database who underwent LGE-MRI and transthoracic echocardiography prior to AF ablation. Based on the degree of LA fibrosis, patients were categorized into four stages as: Utah 1 (<5% LA fibrosis), Utah 2 (5-20% fibrosis), Utah 3 (20-35% fibrosis), and Utah 4 (>35% fibrosis). RESULTS The average pre-ablation LVEF was 60.5%±8.5% (n=24) in Utah stage 1 patients, 55.7%±10.3% (n=240) in Utah stage 2 patients, 51.7±11.5% (n=90) in Utah stage 3 patients, and 48.9%±11.6% (n=30) in Utah stage 4 patients (p<0.001, one-way ANOVA). The percentage of LA fibrosis was significantly negatively correlated to LVEF pre-ablation in a univariate analysis (p<0.001). In a multivariate model accounting for age, gender, AF type, and comorbidities such as diabetes and hypertension, Utah stage remained a significant predictor of pre-ablation EF (p<0.001). CONCLUSION Patients with extensive LA fibrosis appear to have depressed LV function pre-ablation, suggesting that structural remodeling in the LA may also be triggering and promoting remodeling within the ventricular myocardium.

Why hesitate introducing real-time magnetic resonance imaging into the electrophysiological labs?

This editorial refers to ‘Feasibility of real-time magnetic resonance imaging-guided electrophysiology studies in humans’ by P. Sommer et al ., on page 101 Catheter ablation using a standard fluoroscopy imaging guidance provides a cure for a plethora of cardiac arrhythmias and has become the cornerstone of arrhythmia management.1 Nevertheless, since the introduction of complex arrhythmias ablation into the electrophysiological (EP) labs, the need for more accurate imaging visualization and guidance tools has emerged. Despite the massive amount of research and financial investments into the novel ablation and imaging modalities, the outcome of complex ablation procedures has not improved, in fact it has been stable for the last decade. For example, atrial fibrillation (AF) ablation success rates are still reported to be between 40 and 80%.2–4 This dilemma, however, prompted interest in an alternative, complete ‘outside of the box’, concept. One of the imaging/ablation modalities, which has been suggested, is real-time magnetic resonance imaging (MRI)-guided interventional procedure. Cardiac MRI is considered a great tool to help detecting the anatomy, function, and viability of the myocardium.5 Moreover, MRI imaging is an ideal method to detect and quantify critical …

Cardiac ECV is more robust than post-contrast cardiac T1 for evaluating temporal changes in LV fibrosis

Background Post-contrast cardiac T1 measurement has been reported to be correlated with interstitial fibrosis burden. However, post-contrast cardiac T1 can also be influenced by a variety of confounders, including: cardiac function, renal function, hematocrit, magnetic field strength, contrast agent type and dosage, and specific delayed imaging time after contrast agent administration. To compensate for these confounders, investigators have proposed to measure extracellular volume (ECV). Despite the advantages of ECV over cardiac T1, systematic studies comparing the two measurements are lacking [1]. The purpose of this study was to compare the effectiveness of post-contrast cardiac T1 and ECV for evaluating the temporal changes in left ventricular (LV) fibrosis in an established canine model with chronic atrial fibrillation (AF)[2].