Obesity: the perfect storm for heart failure.

Obesity condition causes morphological and functional alterations involving the cardiovascular system. These can represent the substrates for different cardiovascular diseases, such as atrial fibrillation, coronary artery disease, sudden cardiac death, and heart failure (HF) with both preserved ejection fraction (EF) and reduced EF. Different pathogenetic mechanisms may help to explain the association between obesity and HF including left ventricular remodelling and epicardial fat accumulation, endothelial dysfunction, and coronary microvascular dysfunction. Multi-imaging modalities are required for appropriate recognition of subclinical systolic dysfunction typically associated with obesity, with echocardiography being the most cost-effective technique. Therapeutic approach in patients with obesity and HF is challenging, particularly regarding patients with preserved EF in which few strategies with high level of evidence are available. Weight loss is of extreme importance in patients with obesity and HF, being a primary therapeutic intervention. Sodium-glucose co-transporter-2 inhibitors have been recently introduced as a novel tool in the management of HF patients. The present review aims at analysing the most recent studies supporting pathogenesis, diagnosis, and management in patients with obesity and HF.

Impact of sacubitril/valsartan and gliflozins on cardiac resynchronization therapy response in ischemic and non-ischemic heart failure patients.

AIMS: Angiotensin receptor-neprilysin inhibitor (ARNi) and sodium-glucose co-transporter 2 inhibitor (SGLT2i) improve outcomes in heart failure with reduced ejection fraction (HFrEF) patients, however their effects in cardiac resynchronization therapy (CRT) recipients have been scarcely explored. This study investigated whether ARNi and SGLT2i 1) improve the rate of clinical and echocardiographic CRT response and 2) have different impact based on the ischemic or non-ischemic etiology. METHODS: HFrEF patients referred for CRT implant were grouped in no treatment (group 1), only ARNi (group 2) and both ARNi and SGLT2i (group 3). Clinical and echocardiographic response were evaluated at 12 months. RESULTS: A total of 178 patients were enrolled. At one-year follow-up, 74.4% patients in group 2 (p = 0.031) and 88.9% in group 3 (p = 0.014) were classified as clinical responders vs 54.5% in the no treatments group. In multivariable analysis, ARNi/SGLT2i use was an independent predictor of CRT response (OR 3.72; CI 95%, 1.40-10.98; p = 0.011), confirmed in both groups 2 and 3. At 12 months, the median Δ LVEF increase was 6% and 8.5% in groups 2 and 3 respectively, vs 4.5% in group 1 (p = 0.042 and p = 0.029) with significantly more echocardiographic responders in groups 2 and 3 (76% and 78% vs 50%, p = 0.003 and p = 0.036). Significantly more ischemic HFrEF patients than non-ischemic were considered clinical and echocardiographic responders in the treatment groups. CONCLUSIONS: ARNi alone or in combination with SGLT2i in CRT patients improves the clinical and echocardiographic response at 12 months. Ischemic patients seem to benefit more from these treatments.

One-year outcomes in patients undergoing very high-power short-duration ablation for atrial fibrillation.

BACKGROUND: The very high-power short-duration (vHPSD) temperature-controlled ablation (vHPSD) improves the efficiency of pulmonary vein isolation (PVI) procedures. We evaluated the procedural and 12-months outcomes in atrial fibrillation (AF) patients undergoing PVI by means of vHPSD ablation. In patients with AF or atrial tachyarrythmia (AT) recurrence undergoing a redo procedure the durability of the PVI was investigated. METHODS: Consecutive paroxysmal/persistent AF patients undergoing PVI with the vHPSD ablation strategy (90 W, for 4 s) were enrolled. The rate of PVI, first-pass isolation, acute reconnection, and procedural complications were evaluated. Follow-up examinations and EKG were scheduled at 3,6, and 12 months. In case of AF/AT recurrence, patients underwent a redo procedure. RESULTS: Overall, 163 AF patients (29 persistent and 134 paroxysmal) were enrolled. The PVI was reached in 100% of patients (88% at the first pass). The rate of acute reconnection was 2%. The radiofrequency, fluoroscopy and procedural times were respectively 5.5 ± 1 min, 9 ± 1 min and 75 ± 20 min. No death, tamponade nor steam pops occurred; however, 5 patients had vascular complications. The 12-months freedom from AF/AT recurrence was 86% in both paroxysmal and persistent patients. Overall, 9 patients underwent a redo procedure, and in 4 all veins were still isolated, whereas in 5 pulmonary vein reconnections were found. The PVI durability was 78%. No overt clinical complications were observed in the follow-up. CONCLUSIONS: The vHPSD ablation represents an effective and safe ablation strategy to achieve PVI. The 12-months follow-up showed high freedom from AF/AT recurrence and a good safety profile.

Prospective evaluation of local impedance drop to guide left atrial posterior wall ablation with high power.

BACKGROUND: Local impedance (LI) drop predicts acute conduction block during pulmonary vein isolation (PVI). Whether the LI drop predicts also the achievement of left atrial posterior wall isolation (LAPWI) in persistent atrial fibrillation (PersAF) patients is unknown. We evaluated the efficacy and the safety of LI drop-guided LAPW ablation by using high power (50 watts) and investigated the impact of ablation parameters on the LI drop. METHODS: We included consecutive PersAF patients underwent PVI and both roof line and floor line completion to achieve LAPWI with a novel contact force (CF)- and LI-featured catheter (IntellaNAV Stablepoint™). For each radiofrequency (RF) application, we targeted a LI drop of 25 ohms. RESULTS: Out of 30 patients, first-pass floor line block was achieved in 26 (87%) and first-pass roof line block in 17 (57%), resulting in first-pass LAPWI in 14 patients (47%). After touch-up ablations, LAPWI was achieved in 28 patients (93%) with endocardial ablation only. No procedural nor 1-month complications occurred. Overall, 877 RF applications were delivered: 787 ablation tags (89%) were associated with acute conduction block, while 90 (11%) were located at sites of acute gaps in either the roof or floor line. LI drop values were greater at segments with acute block than those with gaps (p < 0.001). At multivariable analysis, only LI drop and RF time remained independently associated with the acute block (p < 0.001; p = 0.001). CONCLUSIONS: LI drop-guided LAPWI at a fixed power of 50 W was effective and did not lead to complications. LI drop was the most important predictor of acute conduction block.

Cavotricuspid isthmus ablation by means of very high power, short-duration, temperature-controlled lesions.

BACKGROUND: A very high-power short-duration (vHPSD) strategy of radiofrequency (RF) ablation aims to minimize conductive heating and increase resistive heating. We evaluated the feasibility, efficacy and safety of the vHPSD ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL). METHODS: This prospective non-randomized study enrolled 28 consecutive patients (FAST Group) with typical AFL undergoing CTI ablation. The vHPSD ablation was performed applying 90 W, for 4 s, with an irrigation of 8 ml/min. Thirty consecutive patients who, previously, underwent CTI ablation by means of a contact force surrounding flow catheter guided by ablation index (500) served as control group (AI Group). RESULTS: In the FAST Group, the mean CTI length was 29 ± 6 mm, and the mean number of RF tags was 20 ± 9. The CTI bidirectional "first pass" block was reached in 25 (89%) patients. There were no major procedural complications. After a mean follow-up of 6 ± 2 months, one (3.5%) patient had arrhythmia recurrence. The vHPSD ablation was as effective as AI-guided ablation in achieving acute CTI block (rate of first pass 89% vs 93%, p = 0.59), with a shorter RF time (88 ± 40 s vs 492 ± 269 s, p < 0.001) and similar procedure (30 ± 4 min vs 34 ± 10 min, p = 0.5) and fluoroscopy time (103 ± 29 vs 108 ± 52 s, p = 0.7). At 8 months, the freedom from AFL recurrence was 96% in the FAST group and 97% in the AI group. CONCLUSIONS: Our preliminary data show that the vHPSD ablation represents an effective and safe ablation strategy to achieve bidirectional block for the treatment of typical AFL.

Insulin Resistance and Vitamin D Deficiency: A Link Beyond the Appearances.

Vitamin D is a steroid hormone that plays a key role in the regulation of body homeostasis, including cardiovascular function. Although the chronic deficiency of vitamin D is associated with cardiovascular risk factors, as well as with an adverse prognosis, randomized controlled trials have failed in demonstrating that dietary vitamin D supplementation could ameliorate the prognosis of patients with cardiovascular diseases, and suggested that vitamin D deficiency is the expression of the effects of other determinants of cardiovascular risk. Thus, the supplementation of vitamin D is not sufficient to improve the cardiovascular risk profile and prognosis. Insulin resistance is a complex phenomenon that plays a key role in the pathogenesis of conventional cardiovascular risk factors. Interestingly, defects of vitamin D and insulin resistance have a superimposable epidemiological distribution. According to the common view, Insulin resistance is considered the direct or indirect consequence of vitamin D deficiency. However, it is also reasonable to speculate that the deficit or the impaired action of vitamin D, in some circumstances, could be the result of the same pathogenic mechanisms responsible of insulin resistance development. In this case, vitamin D deficiency could be considered an epiphenomenon of insulin resistance. Insulin resistance is a reversible condition, being possibly ameliorated by physical activity and hypocaloric diets. Notably, both physical exercise and energy-restricted dietary regimens are associated with an increase of vitamin D levels. These findings indicate that improving insulin resistance condition is a necessary step to ameliorate vitamin D supplementation-based strategies in cardiovascular prevention.

Exercise Training: The Holistic Approach in Cardiovascular Prevention.

Nowadays, there are robust clinical and pathophysiological evidence supporting the beneficial effects of physical activity on cardiovascular (CV) system. Thus, the physical activity is considered a key strategy for CV prevention. In fact, exercise training exerts favourable effects on all risk factors for CV diseases (i.e. essential hypertension, type 2 diabetes mellitus, hypercholesterolemia, obesity, metabolic syndrome, etc…). In addition, all training modalities such as the aerobic (continuous walking, jogging, cycling, etc.) or resistance exercise (weights), as well as the leisure-time physical activity (recreational walking, gardening, etc) prevent the development of the major CV risk factors, or delay the progression of target organ damage improving cardio-metabolic risk. Exercise training is also the core component of all cardiac rehabilitation programs that have demonstrated to improve the quality of life and to reduce morbidity in patients with CV diseases, mostly in patients with coronary artery diseases. Finally, it is still debated whether or not exercise training can influence the occurrence of atrial and ventricular arrhythmias. In this regard, there is some evidence that exercise training is protective predominantly for atrial arrhythmias, reducing the incidence of atrial fibrillation. In conclusion, the salutary effects evoked by physical acitvity are useful in primary and secondary CV prevention.

In vivo biophysical characterization of very high power, short duration, temperature-controlled lesions.

INTRODUCTION: A very high-power short-duration (vHPSD) strategy of radiofrequency (RF) ablation aims to minimize conductive heating and increase resistive heating. This study aimed to clarify the contribution of contact force (CF) and temperature and their interrelationship in making an adequate lesion with the vHPSD catheter. METHODS: We enrolled 46 consecutive patients undergoing first catheter ablation for atrial fibrillation (AF). The vHPSD ablation was performed applying 90 W, for 4 s, with an irrigation of 8 ml/min. During an application, an impedance drop (ID) ≥10 Ω was regarded as an adequate lesion formation. RESULTS: The mean procedural time was 95 ± 15 min. First-pass isolation was reached in 89% of patients and at the end of the procedure all pulmonary veins were isolated. No steam pop nor procedural complication occurred. A total of 3829 qualified RF points were analyzed and the median values of ID, CF and maximum temperature were respectively 10.6 (IQR 8.6-13.1) Ohm, 9 (5.8-13.8) g, 46.8 (44.1-49.8) °C. The mean ID significantly increased in parallel with the increasing CF as well as with the increasing maximum temperature. In the multivariable analysis only the CF and the maximum temperature were independent predictors of ID. From receiver operating characteristic curve analysis, a CF of 8 g and a maximum temperature of 47°C are the optimal cutoff discriminatory value for adequate lesion formation. CONCLUSIONS: The vHPSD ablation is highly effective and safe. The CF and the maximum temperature are independent predictors of adequate lesion formation assessed by means of ID.

Appropriate ICD Interventions for Ventricular Arrhythmias Are Predicted by Higher Syntax Scores I and II in Patients with Ischemic Heart Disease.

AIMS: The occurrence of ventricular arrhythmias (VAs) in ischemic heart disease (IHD) patients is related to the presence and extent of fibrotic/scar tissue. As coronary atherosclerosis is the underlying cause of myocardial ischemia and fibrosis, in IHD patients implanted with an implantable cardioverter defibrillator (ICD) we investigated the relation between the VA burden and the complexity of coronary atherosclerotic lesions. METHODS AND RESULTS: In IHD patients who underwent coronary angiography and ICD implant, the Syntax scores I and II (SSI-II), as index of the severity of the coronary atherosclerotic disease, and the occurrence of VA were assessed. Overall 144 patients were included (123 males). Of these 22 patients (15%) experienced at least one episode of VA (cycle length 298 ± 19 msec) that required ICD intervention. The number of episodes per patient and per year was 4 ± 6 and 2.8 ± 4, respectively. Patients that experienced a VA compared to those free from arrhythmic events did not have distinct baseline clinical characteristics except for a higher SS I and SS II (21 (IQR 13-38) vs. 16 (IQR 10-23); p = 0.037; and 50 (IQR 39-62) vs. 42 (IQR 34-50); p = 0.012). In the binary logistic regression analyses the SS I and II were the only independent predictors of VA occurrence. A higher SS II was also associated with an earlier time to first event (p = 0.005). CONCLUSION: Higher SS I-II scores reflect a more severe coronary atherosclerosis and are associated with a greater VA burden. Further studies are needed to better clarify the ability of SSI-II to stratify the risk of IHD patients to develop life-threatening VA.

Does the Age Affect the Outcomes of Cardiac Resynchronization Therapy in Elderly Patients?

BACKGROUND: More and more heart failure (HF) patients aged ≥ 75 years undergo cardiac resynchronization therapy (CRT) device implantation, however the data regarding the outcomes and their predictors are scant. We investigated the mid- to long-term outcomes and their predictors in CRT patients aged ≥ 75 years. METHODS: Patients in the Cardiac Resynchronization Therapy Modular (CRT MORE) Registry were divided into three age-groups: <65 (group A), 65-74 (group B) and ≥75 years (group C). Mortality, hospitalization, and composite event rate were evaluated at 1 year and during long-term follow-up. RESULTS: Patients (n = 934) were distributed as follows: group A 242; group B 347; group C 345. On 12-month follow-up examination, 63% of patients ≥ 75 years displayed a positive clinical response. Mortality was significantly higher in patients ≥ 75 years than in the other two groups, although the rate of hospitalizations for HF worsening was similar to that of patients aged 65-74 (7 vs. 9.5%, respectively; p = 0.15). Independent predictors of death and of negative clinical response were age >80 years, chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD). Over long-term follow-up (1020 days (IQR 680-1362)) mortality was higher in patients ≥ 75 years than in the other two groups. Hospitalization and composite event rates were similar in patients ≥ 75 years and those aged 65-74 (9 vs. 11.8%; p = 0.26, and 26.7 vs. 20.5%; p = 0.06). CONCLUSION: Positive clinical response and hospitalization rates do not differ between CRT recipients ≥ 75 years and those aged 65-74. However, age > 80 years, COPD and CKD are predictors of worse outcomes.

Evaluation of Directed Graph-Mapping in Complex Atrial Tachycardias.

OBJECTIVES: Directed graph-mapping (DGM) is a novel operator-independent automatic tool that can be applied to the identification of the atrial tachycardia (AT) mechanism. In the present study, for the first time, DGM was applied in complex AT cases, and diagnostic accuracy was evaluated. BACKGROUND: Catheter ablation of ATs still represents a challenge, as the identification of the correct mechanism can be difficult. New algorithms for high-density activation mapping (HDAM) render an easier acquisition of more detailed maps; however, understanding of the mechanism and, thus, identification of the ablation targets, especially in complex cases, remains strongly operator-dependent. METHODS: HDAMs acquired with the latest algorithm (COHERENT version 7, Biosense Webster, Irvine, California) were interpreted offline by 4 expert electrophysiologists, and the acquired electrode recordings with corresponding local activation times (LATs) were analyzed by DGM (also offline). Entrainment maneuvers (EM) were performed to understand the correct mechanism, which was then confirmed by successful ablation (13 cases were centrifugal, 10 cases were localized re-entry, 22 cases were macro-re-entry, and 6 were double-loops). In total, 51 ATs were retrospectively analyzed. We compared the diagnoses made by DGM were compared with those of the experts and with additional EM results. RESULTS: In total, 51 ATs were retrospectively analyzed. Experts diagnosed the correct AT mechanism and location in 33 cases versus DGM in 38 cases. Diagnostic accuracy varied according to different AT mechanisms. The 13 centrifugal activation patterns were always correctly identified by both methods; 2 of 10 localized reentries were identified by the experts, whereas DGM diagnosed 7 of 10. For the macro-re-entries, 12 of 22 were correctly identified using HDAM versus 13 of 22 for DGM. Finally, 6 of 6 double-loops were correctly identified by the experts, versus 5 of 6 for DGM. CONCLUSIONS: Even in complex cases, DGM provides an automatic, fast, and operator-independent tool to identify the AT mechanism and location and could be a valuable addition to current mapping technologies.

Modulation of Insulin Sensitivity by Exercise Training: Implications for Cardiovascular Prevention.

The beneficial effects of physical activity on the cardiovascular system nowadays have achieved the relevance of clinical evidence. In fact, several studies have documented the benefits of exercise training in the prevention of the cardiovascular risk. Abnormalities of insulin signaling transduction account for the impairment of insulin sensitivity and development of insulin resistance, which, in turn, is responsible for the enhancement of cardiovascular risk. Insulin sensitivity is related to the degree of physical activity, and physical training has been shown to ameliorate insulin action in insulin-resistant subjects. This effect is mediated by the improvement of the molecular abnormalities that are responsible of the insulin resistance, contributing in this way to restore the physiological insulin sensitivity. However, it should be underlined that mechanisms that account for this phenomenon are extremely complex and still unclear. Further studies are required to better clarify the molecular basis of the exercise-evoked improvement of insulin signal. Graphical abstract.

Impact of drug-eluting stents on left ventricular wall motion after successful reperfusion of first anterior ST elevation myocardial infarction.

BACKGROUND: Timely myocardial reperfusion by primary percutaneous coronary intervention (pPCI) prevents the development of left ventricular (LV) dysfunction after myocardial infarction (MI). We aimed to investigate whether bare-metal stents (BMS) and drug eluting stents (DES) differently affect the recovery of LV function in patients with ST-elevation MI (STEMI). METHODS: Overall 103anterior STEMI patients were retrospectively analyzed. All patients had single vessel disease with culprit lesion at the left anterior descending coronary artery. Patients were categorized in DES group (N.=67) and BMS group (N.=36). Changes in LV contractility were assessed by trans-thoracic echocardiogram as Left Ventricular Wall Motion Score Index (LVWMSI). Follow-up visits were performed between 6 and 12 months after hospital discharge. RESULTS: Compared to baseline, LV ejection fraction (EF) remained unchanged between the two groups at the follow-up; LVWMSI significantly improved in patients treated with DES (1.95±0.25 vs. 1.78±0.38, P<0.05), whereas did not change in those treated with BMS (2.09±0.21 vs. 1.98±0.33, P: not significant). At follow-up the LVWMSI was significantly higher in patients with DES than with BMS (P=0.048). LV end-systolic and end-diastolic volumes (LVESV, LVEDV) significantly increased in patients receiving a BMS, whereas it did not change in those receiving a DES (P<0.05). Multivariate analysis adjusted for age, gender, type of stent (DES or BMS), and type of revascularization (primary PCI or rescue PCI or thrombolysis + PCI) showed that DES implantation was an independent predictor of LVWMSI improvement (OR: 3.8 [1.143-12.969] P=0.03). CONCLUSIONS: DES implantation is associated with a favorable impact on LV remodeling and regional contractility.

Determinants of aortic root dilatation over time in patients with essential hypertension: The Campania Salute Network.

BACKGROUND: Determinants of changes of aortic root dimension over time are not well defined. DESIGN: We investigated whether specific phenotype and treatment exist predicting changes in aortic root dimension in hypertensive patients from the Campania Salute Network. METHODS: N = 4856 participants (age 53 ± 11 years, 44% women) were included. At first and last available echocardiograms, we measured aortic root and a z-score of aortic root (AOz) was generated as the difference between measured and predicted aortic root, derived from a healthy reference population. Aortic root dilatation (ARD) was defined as AOz >75th percentile of distribution. RESULTS: At baseline, 3642 patients (75%) exhibited normal aortic root, and 1214 (25%) ARD. After a follow-up of 6.1 years (interquartile range 3.0-8.8 years), 366 (11%) patients with initial normal aortic root exhibited ARD, whereas 457(38%) with initial ARD exhibited normal aortic root. At multivariate analysis patients with incident ARD were most likely to be women, obese, with left ventricular hypertrophy, lower systolic but higher diastolic blood pressure and stroke volume index at baseline, and higher average value of diastolic blood pressure during follow-up (p < 0.05); whereas patients normalizing their ARD were non-obese women with lower baseline systolic blood pressure, stroke volume index, average diastolic blood pressure during follow-up and longer follow-up time (p < 0.05). Anti-renin-angiotensin system (anti-RAS) was associated with 45% greater probability to normalize aortic root dimension. CONCLUSIONS: Volume (stroke volume index) and pressure loads (diastolic blood pressure) influence aortic root dimension over time. Aortic root normalization, reflecting a more favourable haemodynamic load, is predictable in non-obese women with lower diastolic blood pressure, taking more anti-RAS therapy. This suggest that sex elicits a different response in aortic walls to pathological stimuli.

Predictors of recurrence after durable pulmonary vein isolation for paroxysmal atrial fibrillation.

AIMS: Catheter ablation of paroxysmal atrial fibrillation (AF) reduces AF recurrence, AF burden, and improves quality of life. Data on clinical and procedural predictors of arrhythmia recurrence are scarce and are flawed by the high rate of pulmonary vein reconnection evidenced during repeat procedures after pulmonary vein isolation (PVI). In this study, we identified clinical and procedural predictors for AF recurrence 1 year after CLOSE-guided PVI, as this strategy has been associated with an increased PVI durability. METHODS AND RESULTS: Patients with paroxysmal AF, who received CLOSE-guided PVI and who participated in a prospective trial in our centre, were included in this study. Uni- and multivariate models were plotted to find clinical and procedural predictors for AF recurrence within 1 year. Three hundred twenty-five patients with a mean age of 63 years (CHA2DS2VASc 1 [1-3], left atrium diameter 41 ± 6 mm) were included. About 60.9% were male individuals. After 1 year, AF recurrence occurred in 10.5% of patients. In a binary logistic regression analysis, the diagnosis-to-ablation time (DAT) was found to be the strongest predictor of AF recurrence (P = 0.011). Diagnosis-to-ablation time ≥1 year was associated with a nearly two-fold increased risk for developing AF recurrence. CONCLUSION: The DAT is the most important predictor of arrhythmia recurrence in low-risk patients treated with durable pulmonary vein isolation for paroxysmal AF. Whether reducing the DAT could improve long-term outcomes should be investigated in another trial.

Prospective Randomized Evaluation of High Power During CLOSE-Guided Pulmonary Vein Isolation: The POWER-AF Study.

BACKGROUND: CLOSE-guided atrial fibrillation (AF) ablation is based on contiguous (intertag distance ≤6 mm), optimized (Ablation Index >550 anteriorly and >400 posteriorly) point-by-point radiofrequency lesions. The optimal radiofrequency power remains unknown. METHODS: The POWER-AF study is a prospective, randomized controlled monocentric study including patients with paroxysmal AF, planned for first CLOSE-guided pulmonary vein isolation using a contact force radiofrequency catheter (Thermocool SmartTouch, Biosense Webster, Inc, Irvine, CA). A total of 100 patients were randomized into 2 groups (1:1). The control group received AF ablation using the standard CLOSE protocol (35 W), whereas in the experimental group, pulmonary vein isolation was performed using high power (45 W). Endoscopic evaluation was performed in patients with intraesophageal temperature rise >38.5 °C. RESULTS: The resulting sample size was 96 (48+48) patients. In the high power group, shorter procedure time (80 versus 102 minutes, P<0.001), shorter total radiofrequency application time (16 versus 26 minutes, P<0.001), and radiofrequency time per application (26 versus 37 s anteriorly, P<0.001 and 13 versus 17 s posteriorly, P<0.001) were observed. Endoscopic evaluation (performed in 19/48 versus 25/48 patients respectively, P=0.31) showed an ulcerative perforation in a high power group patient (treated by endoscopic stenting and normalization after ≈4 months) and a superficial ulcerative lesion in a control group patient (conservative treatment). Both occurred following excessive Ablation Index applications (up to 460 and 480, respectively) with excessive contact force (30 g on average, with peaks up to 50 g). Six-months AF recurrence was not significantly different (10% in high power versus 8% in control, P=0.74). CONCLUSIONS: This randomized controlled study shows that a 45 W radiofrequency power CLOSE protocol in patients with paroxysmal AF significantly increases the global procedural efficiency with similar midterm efficacy. However, our study showed a narrower safety margin and a limited increased efficiency at the posterior wall using high power. This advocates against the use of high power in the region neighboring the esophagus.

Insulin Resistance Predicts Severity of Coronary Atherosclerotic Disease in Non-Diabetic Patients.

BACKGROUND: Insulin resistance (IR) in patients with type 2 diabetes mellitus (T2DM) represents a predictor of coronary artery disease (CAD). However, how IR is able to impact the severity of coronary atherosclerosis in non-diabetic patients is unknown. OBJECTIVES: We investigated the relation between the IR and the extent and severity of coronary atherosclerosis in non-diabetic patients referred to coronary angiography (CA) Methods: Consecutive patients undergoing to CA for acute coronary syndromes or stable angina were analyzed. The IR was assessed by mean of the homeostasis model assessment of insulin resistance (HOMA-IR) whereas the SYNTAX score (SS) was used as index of the severity of coronary atherosclerosis Results: Overall, 126 patients were included, with a median SS of 12 (IQR 5.25-20.5). Patients were divided in four groups according to the distribution in quartiles of SS (SS1-2-3-4). A significant correlation between HOMA-IR and SS was observed, especially in women. A progressive increase of HOMA-IR was observed in parallel with the increasing severity (from SS1 to SS4) and extension (1-2-3-vessel disease) of coronary atherosclerosis. Multivariable analysis showed that the HOMA-IR was the strongest independent predictor of severe (SS4) and extensive (three-vessel disease) coronary atherosclerosis. CONCLUSION: Insulin resistance goes hand in hand with the extension and severity of coronary atherosclerosis in non-diabetic patients. The HOMA index is an independent predictor of three-vessel disease at CA. The HOMA index could be useful for risk stratification of CAD even in absence of T2DM.

Reproducibility of pulmonary vein isolation guided by the ablation index: 1-year outcome of the AIR registry.

BACKGROUND: Ablation index (AI) is a new lesion quality marker that has been demonstrated to allow a high single-procedure arrhythmia-free survival in single-center studies. This prospective, multi-center study was designed to evaluate the reproducibility of pulmonary vein (PV) isolation guided by the AI. METHODS: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV isolation and were divided in four study groups according to operator's preference in choosing the ablation catheter (a contact force (ST) or contact force surround flow (STSF) catheter) and the AI setting (330-450 or 380-500 at anterior wall or posterior wall, respectively). RESULTS: At 12 months a high rate of freedom from AF recurrences was observed in patients with both paroxysmal and persistent AF (91% vs 83.3%; P = .039). There was no difference in the rate of AF recurrence among the four study groups (4.5% in group ST330-450, 12.2% in group ST 380-500, 14.9% in group STSF330-450, 9.4% in group STSF380-500; P = .083). Recurrence was also similar between patients treated with a ST (8%) or STSF catheter (12.1%; P = .2), and within patients targeting an AI settings of 330 to 450 (10.9%) or 380 to 500 (10.3%; P = .64). In patients with paroxysmal AF, there was no difference (P = .12) in the 1-year freedom from AF recurrence among 14 operators that performed ≥10 ablation procedure. CONCLUSIONS: An ablation protocol respecting strict criteria for contiguity and quality lesion resulted in high rate of 1-year freedom from AF recurrence, irrespective of the ablation catheters, AI settings, and operator.