[Leadless pacemakers: results of a survey from implanter centers in the Lombardy region]

BACKGROUND

Transvenous pacing is nowadays the cornerstone of interventional management of bradyarrhythmias. It is still associated, however, with significant complications, mostly related to indwelling transvenous leads or device pocket. In order to reduce these complications, leadless pacemakers have been recently introduced into clinical practice, but no guidelines are yet available to indicate who are those patients that might benefit the most and whether leadless pacing should be preferred in the old or young population. This survey aims to describe the use of leadless pacemaker devices in a real-world setting.

METHODS

Eleven arrhythmia centers in the Lombardy region (out of a total of 17 participating centers) responded to the proposed questionnaire regarding patient characteristics and indications to leadless pacing.

RESULTS

Out of a total of 411 patients undergoing leadless pacing during 4.2 ± 0.98 years, the median age was 77 years, with 0.18% of patients having less than 18 years, 29.9% 18-65 years, 34.3% 65-80 years and 35.6% >80 years. The most common indication was slow atrial fibrillation (49% of patients), followed by atrioventricular block and sinoatrial dysfunction. Two centers reported in-hospital complications.

CONCLUSIONS

Leadless pacemakers proved to be a safe pacing strategy actually destined mostly to elderly patients.

Contact-Force Guided Posterior Wall Isolation as an Adjunctive Ablation Strategy for Persistent Atrial Fibrillation

Background

The efficacy of posterior wall isolation (PWI) on top of pulmonary vein isolation (PVI) in patients affected by persistent atrial fibrillation (AF) is still controversial and little is known about the impact of contact-force (CF) technology.

Objective

In this retrospective study, we present our experience with PWI using CF sensing catheters and its efficacy and safety as an adjunctive ablation strategy on top of PVI for management of patients with persistent and longstanding persistent AF.

Methods

A total of 73 consecutive patients (20.5% female) affected by persistent atrial fibrillation (10.9% long-standing) underwent PWI as an adjunctive therapy to PVI using CF sensing catheters. Outcomes were reported as incidence of atrial arrhythmic recurrences (ARs) lasting >30 seconds at follow up and in addition, in patients provided with insertable cardiac monitors (ICM), as burden of AF or atrial tachycardias (AT) at relevant time points.

Results

PWI was successfully achieved in 65 (89.0%) patients. Two (2.7%) minor vascular procedural complications were observed. At 1 and 2-year follow-up, ARs free survival was observed in 80.5% and 64.1% of patients, respectively with 75.3% of patients off antiarrhythmic drugs at the last follow-up. Ten patients underwent repeat ablations during the follow-up. At multivariate analysis, early ARs within 3 months after procedure, were associated with a two-fold increased risk of late ARs at follow-up. Among patients provided with ICM, PWI on top of PVI was able to reduce the mean AT/AF burden of more than 50% compared with pre-ablation time, reporting very low levels (≤ 5%) over 2 years.

Conclusions

In persistent atrial fibrillation, PWI on top of PVI using CF sensing catheters is safe and effective, providing great reduction of burden of ARs. Early ARs are associated with a greater risk of late recurrences.

P1020Persistent AF patients with limited areas of low voltage have a similar benefit from pulmonary vein isolation as compared to paroxysmal AF patients: insight from the SMOP study

Background

Pulmonary vein isolation (PVI) performed with radio-frequency catheter ablation (CA) is an effective therapy for atrial fibrillation (AF). However previous data have suggested that PVI is less effective in persistent (PER) vs. paroxysmal (PAR) AF. Atrial fibrosis and scar, indeed, are an important substrate involved in persistent AF, and some author correlate them to an increased rate of recurrences after CA. For this reason several adjunctive ablation strategies have been suggested for invasive treatment in PER AF pts. However, there is a lack of evidence on their effectivness in current literature.

Objective

the aim of our study was to assess the rate of AF recurrences in PAR and PER AF patients after a first pulmonary vein isolation (IVP) procedure, and their relationship with low voltage areas of the left atrium assessed by means of high density mapping performed before CA.

Methods

we analyzed 214 patients of the SMOP-AF study (Substrate Mapping as Outcome Predictor in Atrial Fibrillation Ablation), a prospective multi-centric registry enrolling patients with both PAR and PER AF undergoing a first radio-frequency CA procedure aimed to obtain permanent PVI . High-density mapping was performed in sinus rhythm using the CARTO system before PVI. Areas with less than 0,5 mV on mapping were defined as low voltage zone (LVZ); LVZ was indexed on the atrial area. Comparisons were made by cross-tables and Chi-square test or Student T test.

Results

Patients with PER AF (n = 44, 21%) were older (63 ± 9 vs 58 ± 10 yrs, p = 0.01), but notably with no difference in LVEF and atrial dimensions as compared to pts with PAR AF. In addition no statistical difference was observed in procedural variables, except for a greater LVZ area on atrial mapping (8 ± 18 % vs. 5 ± 15 %, p = 0.04) and a longer p wave duration (115 ± 21 msec vs. 103 ± 18 msec, p = 0.01) in pts with PER AF. The incidence of recurrence in the overall population was 15.3% at 3 months and 13.7% from 3 to 12 months: there was no statistical difference in success-rate between PER and PAR pts (respectively 79,5% vs 86% p value = 0.315 in blanking period and 85,3% vs 86,5% p value = 0.8 at 3-12 months follow-up). No statistical difference was observed for ablation variables (number of lesion, contact force, force time integral) in pts with vs. without recurrences.

Conclusion

Our study showed that pulmonary vein isolation alone seems to be as effective in paroxismal and persistent AF patients with low degree of left atrial fibrosis. Our data call into question the idea that PVI alone is not effective in PER AF. High density mapping of the LA could help to identify a subset of PER AF patients with a limited extension of low voltage areas (i.e around 10% of the overall LA surface) that could benefit from PVI without adjunctive ablation strategies. Our data needs to be confirmed in a longer follow-up.

Myotonic dystrophy type 1 and high ventricular vulnerability at the electrophysiological evaluation: ICD yes or not?

A significant number of sudden death (SD) is observed in myotonic dystrophy (DM1) despite pacemaker implantation and some consider the ICD to be the preferential device in patients with conduction disease. According to the latest guidelines, prophylactic ICD implantation in patients with neuromuscular disorder should follow the same recommendations of non-ischemic dilated cardiomyopathy, being reasonable when pacing is needed. We here report a case of DM1 patient who underwent ICD implantation even in the absence of conduction disturbances on ECG and ventricular dysfunction/fibrosis at cardiac magnetic resonance. The occurrence of syncope, non-sustained ventricular tachycardias at 24-Holter ECG monitoring and a family history of SD resulted associated with ventricular fibrillation inducibility at electrophysiological study, favouring ICD implantation. On our advice, DM1 patient with this association of SD risk factors should be targeted for ICD implantation.

P1896Single-procedure success-rate of pulmonary vein isolation using point-by-point tagging lesions algorithm based on contact force technology: preliminary results of the multicentric SMOP study

Background

Pulmonary veins isolation (PVI)is an effective therapy for atrial fibrillation (AF), recommended by current guidelines. However, recurrences after first radio-frequency (RF) catheter ablation (CA) are still high. PV reconnection could be due to ineffective transmural lesions; automated ablation lesion tags (the VisiTag algorithm) based on predefined parameters of catheter stability and contact force (CF) have been developed to allow the detection of ineffective ablation lesion, nevertheless there is a lack of multicenter studies exploring this technology.

Objective

the aim of our study was to assess the rate of recurrence after a first PVI procedure in a large, multicentric Italian population and to explore the efficacy of Visitag algorithm (CARTO 3) used to guide RF ablation of AF.

Methods

we analyzed 214 patients of the SMOP-AF study (Substrate Mapping as Outcome Predictor in Atrial Fibrillation Ablation), a prospective multi-centric study enrolling patients with paroxysmal and persistent AF undergoing a first PVI procedure after an high-density mapping during sinus rhythm. During the procedure, ablation was guided by an automated annotation system in which tag based on predefined parameters were displayed real-time in each lesion site on the electroanatomical map. Visitag settings for the catheter position stability were a 2,5 mm distance limit for at least 7 sec and a minimum CF of 5 g over 30% of the ablation and a FTI>400 g*s. Where available (n=106, 49.5%), Ablation Index (AI), which also incorporates information on delivered RF power, was used instead of FTI to guide RF ablation with a threshold range of 400–550 for anterior/roof and 330–420 for posterior/inferior segments. Minimum and mean contact force, time and power values for each RF-lesion were recorded while both FTI and AI values were calculated automatically by the CARTO system. Comparison between groups were made by cross-tables, Mann-Whitney or Student T test as appropriated.

Results

the mean age of the enrolled population was 59±9 years, left ventricular ejection fraction was 59±9%. AF was paroxysmal in 89.7%, persistent in 10.3% of the patients and refractory to at least one anti-arrhythmic drug in 86.4% of the population. At 3 months follow-up 85% of the patients were free from AF recurrences and the success rate increased to 90.8% at 3–6 months, and 86.3% at 3–12 months follow-up. The mean ablation time was shorter in AI-guided vs. FTI-guided procedures (31±9 vs 46±29 min; p<0.001). There was a trend toward a reduction in AF recurrences when AI vs. FTI was used, both at 6 and 12 months (respectively 5,4% vs 13.6%; p 0.06 and 9.6% vs 18.5%; p 0.08).

Conclusion

PVI isolation using dedicated algorithms developed to guide the effectiveness of RFCA leads to a very high success-rate after a single procedure. The use of AI, which integrates contact force information with delivered power, reduces the procedural time and increases the overall success-rate

P1037Relationship between left atrium low voltage areas and atrial fibrillation radiofrequency ablation success-rate: preliminary results of the SMOP study

Background

radio frequency catheter ablation (CA) is an effective therapy for atrial fibrillation (AF). Some authors have described a potential relationship between the presence of areas of fibrosis in the left atrium (LA) and the success of CA, nevertheless there is a lack of multicenter studies in this field.

Objective

the aim of our study was to assess the relationship between the of presence of low voltage areas of the LA detected during subtrate mapping at the time of the procedure and recurrences of AF after CA.

Methods

we analyzed 214 patients of the SMOP-AF (Substrate Mapping as Outcome Predictor in Atrial Fibrillation Ablation), a prospective multi-centric study enrolling patients with both paroxysmal and persistent AF undergoing a first radio-frequency CA procedure. High-density mapping was performed in sinus rhythm using the CARTO system before performing pulmonary vein isolation. Areas with less than 0,5 mV on mapping were defined as low voltage zone (LVZ), while between 0,5 mV and 1,5 mV intermediate voltage zone (IVZ). IVZ and LVZ were expressed as a percentage of the LA surface. Comparisons were made by Pearson correlation, cross-tables and Chi-square test or Student T test.

Results

the mean age of the enrolled population was 59±9 years, left ventricular ejection fraction was 59±9%, 86.4% of the pts had tested at least one anti-arrhythmic drug. Persistent atrial fibrillation was present in 10.3% of patients. The rate of documented AF recurrence at 3 months was 15,3% (n=29). There was a statistical significant correlation between the presence of IVZ and the rate of recurrences at 3 months (r=0.16, p value 0.03). Patients with IVZ greater than 4% of the left atrium surface showed a higher risk of recurrences (19.5% vs. 8,7%, p value 0.04). No statistical difference was observed in other procedural variables (number of lesions, contact force, force-time integral) among patients with or without recurrences.

Conclusion

Our study showed a relationship between CA short-term success rate and the presence of areas of intermediate voltage zone detected with high-density substrate mapping at the time of the procedure. The presence of areas of intermediate voltage zone greater than 4% of the LA determines a 2.5 folds increased risk of short-term recurrence. Our data needs to be confirmed in a longer follow-up.

Functional status measured by walking impairment questionnaire and cardiovascular risk prediction in peripheral arterial disease: results of the Peripheral Arteriopathy and Cardiovascular Events (PACE) study

The prognostic impact of the functional status of patients with intermittent claudication is still obscure. From the lists of seven general practitioners, we identified all subjects aged 40-80 years (n = 4352). Of those reporting leg symptoms while walking on the Rose questionnaire (n = 760), 60 had a qualifying diagnosis of peripheral arterial disease (PAD). All of them received the Walking Impairment Questionnaire (WIQ). For each patient affected by PAD, three sex- and age-matched controls were selected randomly. After a 24-month follow-up, survival curves showed that PAD patients with WIQ scores > median had a higher cardiovascular risk than controls, and patients with WIQ scores < median had an even poorer prognosis (p < 0.001 for all WIQ domains). In PAD, after adjustment for age, sex, ankle-brachial index and comorbidity, two WIQ domains (ie walking speed and stairclimbing) were associated with cardiovascular events. The cardiovascular risk of claudicants who had a score > median for at least three WIQ domains was intermediate versus the risk of controls and PAD patients with a WIQ score < median, also when adjusted for the covariates indicated above (RR = 3.26, p = 0.019). In intermittent claudication, a worse functional status entails a greater risk of ischemic events versus low functional impairment.

Influence of rs5065 atrial natriuretic peptide gene variant on coronary artery disease

OBJECTIVES

The aim of this study was to investigate the impact of rs5065 atrial natriuretic peptide (ANP) gene variant on coronary artery disease (CAD) and its outcomes and to gain potential mechanistic insights on the association with CAD.

BACKGROUND

Either modified ANP plasma levels or peptide structural alterations have been involved in development of cardiovascular events.

METHODS

Three hundred ninety-three control subjects and 1,004 patients undergoing coronary angiography for suspected CAD (432 stable angina [SA], 572 acute coronary syndrome [ACS]) were genotyped for rs5065 ANP gene variant. Data in SA and ACS groups were replicated in an independent population of 482 stable angina patients (rSA) and of 675 ACS patients, respectively. Clinical follow-up was available for both SA and rSA patients. Plasma N-terminal-proANP, myeloperoxidase, lipoprotein-associated phospholipase A2, and oxidized low-density lipoprotein were assessed in a subgroup of rSA patients.

RESULTS

rs5065 minor allele (MA) was an independent predictor of ACS (odds ratio: 1.90; 95% confidence interval: 1.40 to 2.58, p < 0.001). At follow-up, rs5065 MA was independently associated with a significantly higher rate of major adverse cardiovascular events in the SA group, p < 0.001. Data were replicated in the rSA group at follow-up (p = 0.008). Cox proportional hazard analysis tested by 4 models confirmed higher major adverse cardiovascular events risk in rs5065 MA carriers in both SA and rSA cohorts. Significantly higher myeloperoxidase levels were detected in rs5065 MA carriers (n = 597 [345 to 832 μg/l] vs. n = 488 [353 to 612 μg/l], p = 0.038). No association of rs5065 was observed with N-terminal-proANP levels.

CONCLUSIONS

The MA of rs5065 ANP gene variant associates with increased susceptibility to ACS and has unfavorable prognostic value in CAD.

Carotid artery disease and stroke in patients with peripheral arterial disease. The role of inflammation

Although during the last decade there have been great advances in our knowledge of the epidemiology and pathophysiology of multi-district atherosclerotic disease, little is known about the association between peripheral arterial disease and carotid artery disease. This review was conceived to cast some light on this topic, paying special attention to inflammation which plays a pivotal role in atherosclerosis. An aspect of pathophysiologic and clinical relevance is that the coexistence of carotid disease is more frequent in peripheral arterial disease than in coronary artery disease, not only in terms of carotid stenosis, but also with respect to the presence of hypoechoic unstable plaque. These latter plaques present a large infiltration of macrophages and are associated to high levels of inflammatory markers. In particular, the greater prevalence of hypoechoic carotid plaques in peripheral arterial disease compared to patients with carotid artery disease was poorly related to classic risk factors, but showed an independent association with an increased number of leukocyte and neutrophil cells, which are reliable markers of inflammation. The greater prevalence of hypoechoic unstable carotid plaques could explain why peripheral arterial disease portends higher risk of stroke than coronary artery disease.

Prevalence of hypoechoic carotid plaques in coronary artery disease: relationship with coexistent peripheral arterial disease and leukocyte number

Abstract

In coronary artery disease (CAD), a concomitant peripheral arterial disease (PAD) entails a more severe coronary atherosclerosis. We hypothesized that the severity of carotid artery disease is greater in CAD+PAD than in CAD alone. In 90 CAD and 79 CAD+PAD patients, carotid plaque echolucency was measured by gray-scale median (GSM), and the degree of carotid stenosis by routine Doppler criteria. Plaques were absent in 20 (22.2%) CAD and 8 (10.1%) CAD+PAD patients ( p = 0.035), while the prevalence of carotid stenosis ≥ 50% was 16.7% and 25.3%, respectively ( p = 0.166). The GSM score was 45.1 [21.7–67.7] in CAD+PAD vs 60.1 [44.9–83.1] in CAD alone ( p < 0.001). Consistently, hypoechoic plaques (GSM < 25th percentile) were more common in CAD+PAD than in CAD patients (38.0% vs 11.4%, p < 0.001). On multivariate analysis, CAD+PAD was the only variable significantly associated with hypoechoic plaques (OR = 4.16, 95% CI 1.68–10.28). However, when the leukocyte count was added to the model, it showed the strongest association with hypoechoic plaques (OR = 6.70, 95% CI 2.13–21.10). In conclusion, compared with CAD alone patients, those with concomitant PAD showed a greater prevalence of plaques with characteristics of instability. Thus, our data suggest that in CAD+PAD, evaluation of carotid plaque echogenicity could contribute to improve clinical decision-making and differentiate treatments for individual patients.

[Intermittent claudication in Italy. The Peripheral Arteriopathy and Cardiovascular Events (PACE) study]

BACKGROUND

The epidemiology of intermittent claudication in the primary care settings has been studied almost exclusively in northern European and northern American populations. This article compares the results of the Peripheral Arteriopathy and Cardiovascular Events (PACE) study, the first survey in Italy to assess the prevalence, comorbidity and natural history of intermittent claudication, with those observed in other western countries.

METHODS

From the lists of seven general practitioners, all patients aged 40-80 years (n = 4352) received a Rose questionnaire. In those reporting leg pain while leg pain while walking (n = 760), Doppler examination was performed. Intermittent claudication was defined as an ankle/branchial index of < 0.90, or reduced flow velocity. For each claudicant, three age- and sex-matched controls were randomly selected from patients negative to the questionnaire.

RESULTS

The prevalence of both intermittent claudication (1.6%) and associated cardiovascular disease (34%) tended to be lower in Italy than in the United Kingdom, Netherlands, and North America. Conversely, no between country difference was observed with respect to mortality, which was very high (relative risk 4.08; 95% confidence interval 1.50-10.84, p = 0.006) in the PACE claudicants.

CONCLUSIONS

In this regard it is noteworthy that these patients, who were managed almost exclusively by their general practitioner were undertreated with respect to the use of antiplatelet therapy and correction of risk factors. There is need to alert them to this topic.

Peripheral arterial disease and cardiovascular risk in Italy. Results of the Peripheral Arteriopathy and Cardiovascular Events (PACE) study

OBJECTIVE

Our knowledge about the natural history of peripheral arterial disease (PAD) is derived from studies carried out almost exclusively in northern European and northern American populations. This study was aimed at defining mortality and cardiovascular morbidity of PAD patients in Italy.

METHODS

From the lists of seven general practitioners, we identified all subjects aged 40-80 years (n = 4352). Of those reporting leg symptoms while walking at the Rose Questionnaire (n = 760), 60 (1.6% of the general population) had PAD, as evidenced by an ankle-brachial index of < 0.90 or reduced Doppler flow velocity. For each PAD patient, three sex and age-matched controls negative to the Rose Questionnaire were randomly selected from the general practice lists.

RESULTS

After 24 months of follow-up, 15% of PAD patients died, 8% from cardiovascular disease, and 25% developed a non-fatal cardiovascular event. At Cox analysis, the presence of PAD was associated with an increased risk of all-cause mortality (relative risk 4.03; 95% confidence interval 1.50-10.84; P = 0.006), cardiovascular mortality (relative risk 7.77; 95% confidence interval 1.51-40.16; P = 0.014), and non-fatal cardiovascular events (relative risk 3.11; 95% confidence interval 1.41-6.80; P = 0.005).

CONCLUSIONS

This Italian study shows that, in general practice, symptomatic PAD is associated with a four-fold increased risk of mortality and a nearly eight-fold increased risk of cardiovascular mortality. These figures are quite similar to those reported in northern European and northern American populations. General practitioners, who are the clinicians primarily and largely responsible for the care of these patients, should be alerted to the consequences of PAD.

Metabolic syndrome in peripheral arterial disease: relationship with severity of peripheral circulatory insufficiency, inflammatory status, and cardiovascular comorbidity

OBJECTIVE

Metabolic syndrome is defined by the clustering in the same person of at least three risk factors such as hyperglycemia, hypertriglyceridemia, low levels of high-density lipoprotein, hypertension, and abdominal obesity. In patients with peripheral arterial disease (PAD), we investigated the prevalence of metabolic syndrome and its relationship with the severity of peripheral circulatory insufficiency, inflammatory status, and cardiovascular comorbidity.

METHODS

The presence of metabolic syndrome was assessed in 154 consecutive PAD patients (115 men, 39 women). Inflammatory status was assessed by measuring serum levels of C-reactive protein (CRP).

RESULTS

Metabolic syndrome was present in 51.9% (42.7 % in men, 74.3% in women, P < .01). Patients with an ankle/brachial index (ABI) <0.64 (median) were more likely to have metabolic syndrome than those with less severe PAD (63.9% vs 42.8%, P < .02). The association between a low ABI and metabolic syndrome was maintained after adjustment for age and sex (odds ratio [OR], 2.19; 95% confidence interval [CI], 1.03 to 4.68). Compared with PAD patients without metabolic syndrome, those with the syndrome had greater body mass index (28.2 [25.6; 29.8] kg/m(2) vs 26.1 [24.2; 27.7] kg/m(2), P < .01) and higher levels of CRP (3.9 [1.6; 7.6] mg/L vs 2.0 [1.1; 3.7] mg/L, P < .02). A previous myocardial infarction was documented in 58.2% of patients with and in 37.5% of those without metabolic syndrome (P < .01). At multivariate analysis, metabolic syndrome was significantly associated with previous myocardial infarction also after adjustment for ABI (OR, 2.15; 95% CI, 1.06 to 4.38).

CONCLUSIONS

Metabolic syndrome is present in >50% of PAD patients. The finding that well-established indicators of increased cardiovascular risk such as low ABI and increased CRP levels cluster with metabolic syndrome suggests that identification of this syndrome in these high-risk patients could indicate an even greater risk of cardiovascular events.