Martina Pianelli

Radiofrequency catheter ablation of atrial fibrillation: A cause of silent thromboembolism? Magnetic resonance imaging assessment of cerebral thromboembolism in patients undergoing ablation of atrial fibrillation

Background— Radiofrequency left atrial catheter ablation has become a routine procedure for treatment of atrial fibrillation. The aim of this study was to assess with preprocedural and postprocedural cerebral magnetic resonance imaging the thromboembolic risk, either silent or clinically manifest, in the context of atrial fibrillation ablation. The secondary end point was the identification of clinical or procedural parameters that correlate with cerebral embolism. Methods and Results— A total of 232 consecutive patients with paroxysmal or persistent atrial fibrillation who were candidates for radiofrequency left atrial catheter ablation were included in the study. Pulmonary vein isolation or pulmonary vein isolation plus linear lesions plus atrial defragmentation with the use of irrigated-tip ablation catheters was performed. All of the patients underwent preprocedural and postablation cerebral magnetic resonance imaging. A periprocedural symptomatic cerebrovascular accident occurred in 1 patient (0.4%). Postprocedural cerebral magnetic resonance imaging was positive for new embolic lesions in 33 patients (14%). No clinical parameters such as age, hypertension, diabetes mellitus, previous history of stroke, type of atrial fibrillation, and preablation antithrombotic treatment showed significant correlation with ischemic cerebral embolism. Procedural parameters such as activated clotting time value and, in particular, electric or pharmacological cardioversion to sinus rhythm correlated with an increased incidence of cerebral embolism. Cardioversion was also associated with an increased risk of 2.75 (95% confidence interval, 1.29 to 5.89; P=0.009). Conclusions— Radiofrequency left atrial catheter ablation carries a low risk of symptomatic cerebral ischemia but is associated with a substantial risk of silent cerebral ischemia detected on magnetic resonance imaging. Independent risk factors for cerebral thromboembolism are the level of activated clotting time and, in particular, the electric or pharmacological cardioversion to sinus rhythm during the procedure.

Prevalence of silent cerebral ischemia in paroxysmal and persistent atrial fibrillation and correlation with cognitive function.

OBJECTIVES The aim of this study was to compare the prevalence of silent cerebral ischemia (SCI) and cognitive performance in patients with paroxysmal and persistent atrial fibrillation (AF) and controls in sinus rhythm. BACKGROUND Large registries have reported a similar risk for symptomatic stroke in both paroxysmal and persistent AF. The relationship among paroxysmal and persistent AF, SCI, and cognitive impairment has remained uncharted. METHODS Two hundred seventy subjects were enrolled: 180 patients with AF (50% paroxysmal and 50% persistent) and 90 controls. All subjects underwent clinical assessment, neurological examination, cerebral magnetic resonance, and the Repeatable Battery for the Assessment of Neuropsychological Status. RESULTS At least 1 area of SCI was present in 80 patients (89%) with paroxysmal AF, 83 (92%) with persistent AF (paroxysmal vs. persistent, p = 0.59), and 41 (46%) controls (paroxysmal vs. controls and persistent vs. controls, p < 0.01). The number of areas of SCI per subject was higher in patients with persistent AF than in those with paroxysmal AF (41.1 ± 28.0 vs. 33.2 ± 22.8, p = 0.04), with controls reporting lower figures (12.0 ± 26.7, p < 0.01 for both). Cognitive performance was significantly worse in patients with persistent and paroxysmal AF than in controls (Repeatable Battery for the Assessment of Neuropsychological Status scores 82.9 ± 11.5, 86.2 ± 13.8, and 92.4 ± 15.4 points, respectively, p < 0.01). CONCLUSIONS Patients with paroxysmal and persistent AF had a higher prevalence and number of areas of SCI per patient than controls and worse cognitive performance than subjects in sinus rhythm.

Left atrial appendage morphology and silent cerebral ischemia in patients with atrial fibrillation

BACKGROUND Left atrial appendage (LAA) is the major source of cardiac thrombi in atrial fibrillation (AF) and plays a major role in cardioembolic events. OBJECTIVE To investigate the correlation between LAA morphology and the burden of silent cerebral ischemia (SCI) as a new thromboembolic risk marker in patients with AF. METHODS A total of 348 patients with AF undergoing transcatheter ablation were enrolled. A cerebral magnetic resonance (MR) was performed to assess SCI burden, while LAA morphology was studied by MR or computed tomography and categorized as follows: cactus in 52 (14.9%) patients, chicken wing in 177 (50.9%), wind sock in 101 (29.0%), and cauliflower in 18 (5.2%). RESULTS SCIs were detected in 295 (84.8%) patients, with a median number of lesions of 23. SCI burden was related to LAA complexity: 30.8% and 17.3% patients with cactus, 30.5% and 22.0% with chicken wing, 13.9% and 27.7% with wind sock, and 16.7% and 38.9% with cauliflower LAA morphologies were in the first and fourth quartiles of number of SCI per patient, respectively (P = .035). After adjustment for potential confounders, only age (β 0.12; 95% CI 0.08-0.16; P < .001), chicken wing (β -0.28; 95% CI -0.51 to -0.04; P = .021), wind sock (β 0.38; 95% CI 0.12-0.65; P = .005), and cauliflower (β 0.61; 95% CI 0.07-1.14; P = .026) LAA morphologies were significantly related to SCI burden. CONCLUSION LAA morphology relates to the burden of SCI in AF patients. Future research should corroborate if accessible methods (eg, echocardiography) are able to describe LAA morphology, permitting its use within universal thromboembolic risk predictors in AF patients.

Comparative safety and efficacy of statins for primary prevention in human immunodeficiency virus-positive patients: a systematic review and meta-analysis

The efficacy and safety of different statins for human immunodeficiency virus (HIV)-positive patients in the primary prevention setting remain to be established. In the present meta-analysis, 18 studies with 736 HIV-positive patients receiving combination antiretroviral therapy (cART) and treated with statins in the primary prevention setting were included (21.0% women, median age 44.1 years old). The primary endpoint was the effect of statin therapy on total cholesterol (TC) levels. Rosuvastatin 10 mg and atorvastatin 10 mg provided the largest reduction in TC levels [mean -1.67, 95% confidence interval (CI) (-1.99, -1.35) mmol/L; and mean -1.44, 95% CI (-1.85, -1.02) mmol/L, respectively]. Atorvastatin 80 mg and simvastatin 20 mg provided the largest reduction in low-density lipoprotein (LDL) [mean -2.10, 95% CI (-3.39, -0.81) mmol/L; and mean -1.57, 95% CI (-2.67, -0.47) mmol/L, respectively]. Pravastatin 10-20 mg [mean 0.24, 95% CI (0.10, 0.38) mmol/L] and atorvastatin 10 mg [mean 0.15, 95% CI (0.007, 0.23) mmol/L] had the largest increase in high-density lipoprotein, whereas atorvastatin 80 mg [mean -0.60, 95% CI (-1.09, -0.11) mmol/L] and simvastatin 20 mg [mean -0.61, 95% CI (-1.14, -0.08) mmol/L] had the largest reduction in triglycerides. The mean discontinuation rate was 0.12 per 100 person-years [95% CI (0.05, 0.20)], and was higher with atorvastatin 10 mg [26.5 per 100 person-years, 95% CI (-13.4, 64.7)]. Meta-regression revealed that nucleoside reverse transcriptase inhibitors-sparing regimens were associated with reduced efficacy for statins ability to lower TC. Statin therapy significantly lowers plasma TC and LDL levels in HIV-positive patients and is associated with low rates of adverse events. Statins are effective and safe when dose-adjusted for drug-drug interactions with cART.

Delaying cardioversion following 4-week anticoagulation in case of persistent atrial fibrillation after a transcatheter ablation procedure to reduce silent cerebral thromboembolism: a single-center pilot study.

Background Symptomatic cerebral thromboembolism occurs in 0.4% of transcatheter atrial fibrillation ablation procedures. Silent cerebral events, instead, have recently been reported in up to 14%, especially clustered within patients undergoing cardioversion at the end of the procedure. The present study reports the incidence of silent cerebral thromboembolism, assessed by cerebral MRI, delaying electrical cardioversion, in case of lack of sinus rhythm restoration at the end of the procedure, after 4 weeks of effective anticoagulation. Methods and results Ninety-five consecutive patients with antiarrhythmic drug refractory atrial fibrillation were referred for transcatheter ablation and enrolled in the study. All patients underwent pre-ablation and post-ablation cerebral MRI. Overall, post-ablation cerebral MRI registered new thromboembolism in six (6%) patients. Fifty-five (58%) patients remained in sinus rhythm throughout the procedure and 40 (42%) reported persistent atrial fibrillation, yielding a silent thromboembolism incidence of 5 and 8%, respectively. In particular, silent thromboembolism was registered in one (4%) of the 25 patients achieving sinus rhythm by catheters, in two (18%) of the 11 patients spontaneously restoring sinus rhythm shortly following the procedure and in none of the four patients cardioverted following 4-week anticoagulation. In a matched reference population, a significantly higher percentage of patients (15, 16% vs. 6, 6%; P = 0.03) suffered from a new post-ablation thromboembolism; particularly within patients terminating the procedure in atrial fibrillation. Delaying cardioversion reduced silent cerebral thromboembolism from 38 to 13%. Conclusion Delaying electrical cardioversion after a 4-week anticoagulation period reduced the risk of silent cerebral thromboembolism and is a viable and safer option in patients terminating a transcatheter ablation procedure in atrial fibrillation.

Heart failure in patients with human immunodeficiency virus: a review of the literature.

Coronary artery disease represents the leading cause of death for HIV patients treated with highly active antiretroviral treatment. Besides this, an extensive amount of data related to the risk of overt heart failure and consequently of atrial fibrillation and sudden cardiac death (SCD) in this population has been reported. It seems that persistent deregulation of immunity in HIV-infected patients is a common pathway related to both of these adverse clinical outcomes. Despite the fact that atrial fibrillation and heart failure are relatively common in HIV, few data are reported about screening, diagnosis, and potential treatment of these conditions.

The beneficial effect of extracorporeal shockwave myocardial revascularization: Two years of follow-up

OBJECTIVES Despite the advancements achieved by revascularization technique and pharmacological therapies, the number of patients with refractory angina (RA) is still high, carrying together a poor prognosis. Experimental data and small clinical studies suggest that the use of extracorporeal shockwave myocardial revascularization (ESMR) might improve symptoms of angina in patients with RA. The aim of our study is to evaluate the efficacy of cardiac shock wave therapy in a long term follow-up of patients with coronary artery disease (CAD) otherwise not suitable for revascularization. METHODS We performed a prospective study enrolling patients with RA despite optimal medical therapy and without indication for further PCI or CABG. Characteristics such as angina class scores (CCS class score), nitroglycerin consumption and hospitalization were compared at baseline and 1, 6 and 12months after ESMR therapy. RESULTS We enroll 72 patients with a mean age of 74.6±14.7years. We treated 440 echocardiographical segments of ischemical myocardium. During the longest published follow-up (2.88±1.65years, range 0.63-6.11) there was a significant reduction of medium CCS class score (from 2.78±0.67 to 1.44±0.6; p=0.0002), nitroglycerin consumption (67% vs 21%; p<0.001) and hospitalization rate (40% vs 18%; p<0.03). CONCLUSION Our study confirms the beneficial effect of ESMR therapy on cardiac symptoms and the possibility to reduce hospitalizations in patients with refractory angina also in a long term follow up. It supports a role for ESMR as a non-invasive therapeutic option for patients with RA.