Avi Sabbag

Contemporary rates of appropriate shock therapy in patients who receive implantable device therapy in a real-world setting: From the Israeli ICD Registry

BACKGROUND Implantable cardioverter-defibrillators (ICDs) have become the mainstay of preventive measures for sudden cardiac death (SCD). However, there are limited data on rates of appropriate life-saving ICD shock therapies in contemporary real-life settings. OBJECTIVE The purpose of the study was to evaluate the rate of appropriate life-saving ICD shock therapies in a contemporary registry. METHODS The Israeli ICD Registry includes all implants and other ICD operative procedures nationwide. The present study comprises 2349 consecutive cases who were enrolled in the Registry and prospectively followed up for information regarding survival, hospitalizations, and ICD therapies since 2010. RESULTS Kaplan-Meier survival analysis showed that the rate of appropriate ICD shock therapy at 30-month follow-up was 2.6% among patients who received an ICD for primary prevention compared with 7.4% among those who received a device for secondary prevention (log-rank P < .001). Rates of appropriate ICD shocks among primary prevention patients were 1.1% at 1-year of follow-up and 2.6% at 30 months, whereas the corresponding rates in the secondary prevention group were 3.8% at 1 year and 7.4% at 30 months (log-rank P < .001). A total of 253 patients (4.8%) died during follow-up, 65% of noncardiac causes. CONCLUSION Rates of life-saving appropriate ICD shock therapies among patients implanted with a defibrillator for the primary prevention of SCD in a contemporary real-world setting are lower than reported previously. These findings suggest a need for improved risk stratification and patient selection in this population.

Cardiac rehabilitation following an acute coronary syndrome: Trends in referral, predictors and mortality outcome in a multicenter national registry between years 2006–2013: Report from the Working Group on Cardiac Rehabilitation, the Israeli Heart Society

Background Utilization of cardiac rehabilitation is suboptimal. The aim of the study was to assess referral trends over the past decade, to identify predictors for referral to a cardiac rehabilitation program, and to evaluate the association with one-year mortality in a large national registry of acute coronary syndrome patients. Design and methods Data were extracted from the Acute Coronary Syndrome Israeli Survey national surveys between 2006–2013. A total of 6551 patients discharged with a diagnosis of acute coronary syndrome were included. Results Referral to cardiac rehabilitation following an acute coronary syndrome increased from 38% in 2006 to 57% in 2013 (p for trend < 0.001). Multivariate modeling identified the following independent predictors for non-referral: 2006 survey, older age, female sex, past stroke, heart or renal failure, prior myocardial infarction, minority group, and lack of in-hospital cardiac rehabilitation center (all p < 0.01). Kaplan-Meier survival analyses showed one-year survival rates of 97% vs 92% in patients referred for cardiac rehabilitation as compared to those not referred (log-rank p < 0.01). Multivariate analysis showed that referral for cardiac rehabilitation was associated with a 27% mortality risk reduction at one-year follow-up (p = 0.03). Consistently, a 32% lower one-year mortality risk was evident in a propensity score matched group of 3340 patients (95% confidence interval 0.48–0.95, p = 0.02). Conclusions Over the past decade there was a significant increase in cardiac rehabilitation referral following an acute coronary syndrome. However, cardiac rehabilitation is still under-utilized in important high-risk subsets of this population. Patients referred to cardiac rehabilitation have a lower adjusted mortality risk.

Obesity and exercise-induced ectopic ventricular arrhythmias in apparently healthy middle aged adults:

Background Obesity and overweight are strongly associated with cardiovascular morbidity and mortality. However, there are limited data on the association between excess weight and the risk of ectopic ventricular activity. Design and methods We investigated the association between body mass index (BMI) and the risk for ectopic ventricular activity (defined as multiple ventricular premature beats (≥3), ventricular bigeminy, nonsustained ventricular tachycardia or sustained ventricular tachycardia) during exercise stress testing among 22,516 apparently healthy men and women who attended periodic health screening examinations between the years 2000 and 2014. All subjects had completed maximal exercise stress testing annually according to the Bruce protocol. Subjects were divided at baseline into three groups: normal weight (BMI ≥ 18.5 kg/m2 and<25; N = 9,994), overweight (BMI ≥ 25 and < 30; N = 9,613) and obese (BMI ≥ 30; N = 2,906). Results The mean age of study subjects was 47 ± 10 years and 72% were men. Kaplan–Meier survival analysis showed that the cumulative probability for the development of exercise-induced ectopic ventricular activity arrhythmias was highest among obese subjects, intermediate among overweight subjects and lowest among subjects with normal weight (3.4%, 2.7% and 2.2% respectively; p < 0.001). Multivariate binary logistic regression with repeated measures of 92,619 ESTs, showed that obese subjects were 33% more likely to have ectopic ventricular arrhythmias during exercise compared with subjects with normal weight (p = 0.005), and that each 1 kg/m2 increase in BMI was associated with a significant 4% (p = 0.002) increased adjusted risk for exercise-induced ventricular arrhythmias. Conclusion Obesity is independently associated with increased likelihood of ectopic ventricular arrhythmia during exercise.

Poor Heart Rate Recovery Is Associated With the Development of New-Onset Atrial Fibrillation in Middle-Aged Adults

OBJECTIVE To investigate the association between heart rate recovery (HRR) and new-onset atrial fibrillation (AF) in middle-aged adults. PATIENTS AND METHODS Heart rate recovery was calculated using the exercise stress test in 15,729 apparently healthy self-referred men and women who attended periodic health screening examinations between January 2000, and December 2015. All participants completed the maximal exercise stress test according to the Bruce protocol and were followed clinically on a yearly basis for a median of 6.4±4 years. The primary end point was new-onset AF. Participants were grouped according to HRR at 5 minutes, dichotomized at the median value (<73 beats/min). RESULTS Participants with low HRR were older, were more commonly men, had a higher rate of comorbidities, and were less fit. Kaplan-Meier survival analysis revealed that the cumulative probability of AF at 6 years was higher in participants with low HRR (2.1%) than in those with high HRR (0.6%) (log-rank, P<.001). Older age, male sex, obesity resting heart rate, and ischemic heart disease were all associated with increased AF risk in a univariate Cox regression model (P<.05 for all). Multivariate Cox regression analysis revealed that low HRR was independently associated with increased AF risk (hazard ratio, 1.92; 95% CI, 1.3-2.8; P<.001) after adjustment for multiple confounders. CONCLUSION Lower HRR is independently associated with the development of new-onset AF during long-term follow-up in middle-aged adults.

Precipitating Factors for Acute Heart Failure Hospitalization and Long-term Survival

AbstractHeart failure (HF) patients have frequent exacerbations leading to high consumption of medical services and recurrent hospitalizations.Different precipitating factors have various effects on long-term survival.We investigated 2212 patients hospitalized with a diagnosis of either acute HF or acute exacerbation of chronic HF. Patients were divided into 2 primary precipitant groups: ischemic (N = 979 [46%]) and nonischemic (N = 1233 [54%]). The primary endpoint was all-cause mortality.Multivariate analysis demonstrated that the presence of a nonischemic precipitant was associated with a favorable in-hospital outcome (OR 0.64; CI 0.43–0.94), but with a significant increase in the risk of 10-year mortality (HR 1.12; CI 1.01–1.21). Consistently, the cumulative probability of 10-year mortality was significantly higher among patients with a nonischemic versus ischemic precipitant (83% vs 90%, respectively; Log-rank P value <0.001). Subgroup analysis showed that among the nonischemic precipitant, the presence of renal dysfunction and infection were both associated with poor short-term outcomes (OR 1.56, [P < 0.001] and OR 1.35 [P < 0.001], respectively), as well as long-term (HR 1.59 [P < 0.001] and HR 1.24 [P < 0.001], respectively).Identification of precipitating factors for acute HF hospitalization has important short- and long-term implications that can be used for improved risk stratification and management.

The prognostic significance of improvement in exercise capacity in heart failure patients who participate in cardiac rehabilitation programme

Introduction There are limited contemporary data regarding the association between improvement in cardiovascular fitness in heart failure patients who participate in a cardiac rehabilitation programme and the risk of subsequent hospitalisations. Methods The study population comprised 421 patients with heart failure who participated in our cardiac rehabilitation programme between the years 2009 and 2016. All were evaluated by a standard exercise stress test before initiation, and underwent a second exercise stress test on completion of 3 ± 1 months of training. Participants were dichotomised by fitness level at baseline, according to the percentage of predicted age and sex norms achieved. Each group was further divided according to its degree of functional improvement, between the baseline and the follow-up exercise stress test. Major improvement was defined as improvement above the median value in each group. The combined primary endpoint was cardiac hospitalisation or all-cause mortality. Results A total of 211 (50%) patients had low baseline fitness (<73% (median)) for age and sex-predicted metabolic equivalents of task value. Compared to patients with higher fitness, those with a low baseline fitness were more commonly smokers, had diabetes and were obese (P < 0.05 for all). Multivariable Cox proportional hazard regression analysis showed that, independent of baseline capacity, an improvement of 5% of predicted fitness was associated with a corresponding 10% reduced risk of cardiac hospitalisation or all-cause mortality (P < 0.001). Conclusion In heart failure patients participating in a cardiac rehabilitation programme, improved cardiovascular fitness is associated with reduced mortality or cardiac hospitalisation risk during long-term follow-up, independent of baseline fitness.

Temporal trends and outcomes associated with atrial fibrillation observed during acute coronary syndrome: Real-world data from the Acute Coronary Syndrome Israeli Survey (ACSIS), 2000-2013: Trends in atrial fibrillation complicating ACS

The past decade has brought major advances in therapy of patients presenting with acute coronary syndromes (ACS).

Ventricular Tachycardia Radiofrequency Ablation with Extracorporeal Membrane Oxygenation

Introduction: Cases of ventricular tachycardia (TV) with hemodynamic compromise present a challenge in achieving non-inducibility by radiofrequency catheter ablation (RFCA). We report our experience of VT RFCA facilitated by elective mechanical circulatory support. Methods and results: Five patients with hemodynamically unstable, recurrent ventricular arrhythmias that were unresponsive to medical therapy underwent extracorporeal membrane oxygenation (ECMO) assisted RFCA of scar related VT. All underwent RFCA under general anesthesia and were connected to an ECMO circuit maintained at minimum flow of 1.5 L /min. In case of VT or VF the blood flow of the ECMO circuit was increased to 4 L/min to allow hemodynamic stability and adequate systemic organ perfusion. A total of 8 VTs were observed. In 4 cases, we mapped during VT the critical isthmus was found and ablated. Four VTs were targeted by substrate mapping only. Complete success, defined as non-inducibility with aggressive program stimulation of any VT, was achieved in 4 patients. In a single patient, a non-clinical VT was still inducible. He died of septic shock 24 hour after the procedure. The remaining 4 were free of ventricular arrhythmia as proven by implanted defibrillator interrogation, over a median follow up of 16 months. Conclusion: ECMO implantation for VTRFCA is safe and assists in reaching the desired endpoint of noninducibility. This approach should be considered in high risk patients who may not otherwise tolerate such procedures.

Effect of Chewing vs Swallowing Ticagrelor on Platelet Inhibition in Patients With ST-Segment Elevation Myocardial Infarction: A Randomized Clinical Trial

Importance Dual anti-platelet therapy represents standard care for treating patients with ST-segment elevation myocardial infarction (STEMI). Ticagrelor is a direct-acting P2Y12 inhibitor and, unlike clopidogrel and prasugrel, does not require metabolic activation. Objective To evaluate whether chewing a loading dose (LD) of ticagrelor, 180 mg, vs traditional oral administration of an equal dose enhances platelet inhibition at 30 minutes and 1 hour after LD administration in patients with STEMI. Design, Setting, and Participants A randomized clinical trial was conducted in adults aged 30 to 87 years from May to October 2016 in a large tertiary care center. Analyses were intention-to-treat. Interventions Fifty patients with STEMI were randomized to either chewing an LD of ticagrelor, 180 mg, or standard oral administration of an equal dose. Main Outcomes and Measures P2Y12 reaction units were evaluated using VerifyNow (Accumentrics) at baseline, 30 minutes, 1 hour, and 4 hours after LD. Results Baseline characteristics were similar in both groups. The mean (SD) of P2Y12 reaction units in the chewing group compared with the standard group at baseline, 30 minutes, 1 hour, and 4 hours after ticagrelor LD were 224 (33) vs 219 (44) (95% CI, −16.77 to 27.73; P = .26), 168 (78) vs 230 (69) (95% CI, −103.77 to −19.75; P = .003), 106 (90) vs 181 (89) (95% CI, −125.15 to −26.29; P = .005), and 43 (41) vs 51 (61) (95% CI, −36.34 to 21.14; P = .30), respectively. Platelet reactivity in the chewing group was significantly reduced by 24% at 30 minutes after LD (95% CI, 19.75 to 103.77; P = .001). The relative inhibition of platelet aggregation in the chewing vs the standard group were 51% vs 10% (95% CI, 13.69 to 67.67; P = .005) at 1 hour and 81% vs 76% (95% CI, −12.32 to 16.79; P = .24) at 4 hours, respectively. Major adverse cardiac and cardiovascular event rate at 30 days was low (4%) and occurred in 1 patient in each group (95% CI, 0.06 to 16.93; P > .99). Conclusions and Relevance Chewing an LD of ticagrelor, 180 mg, in patients with STEMI is feasible and facilitates better early platelet inhibition compared with a standard oral LD. Larger studies are warranted to see if our preliminary findings translate into clinical outcomes. Trial Registration clinicaltrials.gov Identifier: NCT02725099

Feasibility and Safety of Evaluating Patients with Prior Coronary Artery Disease Using an Accelerated Diagnostic Algorithm in a Chest Pain Unit.

An accelerated diagnostic protocol for evaluating low-risk patients with acute chest pain in a cardiologist-based chest pain unit (CPU) is widely employed today. However, limited data exist regarding the feasibility of such an algorithm for patients with a history of prior coronary artery disease (CAD). The aim of the current study was to assess the feasibility and safety of evaluating patients with a history of prior CAD using an accelerated diagnostic protocol. We evaluated 1,220 consecutive patients presenting with acute chest pain and hospitalized in our CPU. Patients were stratified according to whether they had a history of prior CAD or not. The primary composite outcome was defined as a composite of readmission due to chest pain, acute coronary syndrome, coronary revascularization, or death during a 60-day follow-up period. Overall, 268 (22%) patients had a history of prior CAD. Non-invasive evaluation was performed in 1,112 (91%) patients. While patients with a history of prior CAD had more comorbidities, the two study groups were similar regarding hospitalization rates (9% vs. 13%, p = 0.08), coronary angiography (13% vs. 11%, p = 0.41), and revascularization (6.5% vs. 5.7%, p = 0.8) performed during CPU evaluation. At 60-days the primary endpoint was observed in 12 (1.6%) and 6 (3.2%) patients without and with a history of prior CAD, respectively (p = 0.836). No mortalities were recorded. To conclude, Patients with a history of prior CAD can be expeditiously and safely evaluated using an accelerated diagnostic protocol in a CPU with outcomes not differing from patients without such a history.