Reassessing the role of antitachycardia pacing in fast ventricular arrhythmias in primary prevention implantable cardioverter-defibrillator recipients: Results from MADIT-RIT

BACKGROUND: In Multicenter Automatic Defibrillator Implantation Trial - Reduce Inappropriate Therapy (MADIT-RIT), high-rate cutoff (arm B) and delayed therapy (arm C) reduced the risk of inappropriate implantable cardioverter-defibrillator (ICD) interventions when compared with conventional programming (arm A); however, appropriate but unnecessary therapies were not evaluated. OBJECTIVE: The purpose of this study was to assess the value of antitachycardia pacing (ATP) for fast ventricular arrhythmias (VAs) ≥ 200 beats/min in patients with primary prevention ICD. METHODS: We compared ATP only, ATP and shock, and shock only rates in patients in MADIT-RIT treated for VAs ≥ 200 beats/min. The only difference between these randomized groups was the time delay between ventricular tachycardia detection and therapy (3.4 seconds vs 4.9 seconds vs 14.4 seconds). RESULTS: In arm A, 11.5% patients had events, the initial therapy was ATP in 10.5% and shock in 1%, and the final therapy was ATP in 8% and shock in 3.5%. In arm B, 6.6% had events, 4.2% were initially treated with ATP and 2.4% with shock, and the final therapy was ATP in 2.8% and shock in 3.8%. In arm C, 4.7% had events, 2.5% were initially treated with ATP and 2.3% with shock, and the final therapy was ATP in 1.4% and shock in 3.3%. The final shock rate was similar in arm A vs arm B (3.5% vs 3.8%; P = .800) and in arm A vs arm C (3.5% vs 3.3%; P = .855) despite the marked discrepancy in initial ATP therapy utilization. CONCLUSION: In MADIT-RIT, there was a significant reduction in ATP interventions with therapy delays due to spontaneous termination, with no difference in shock therapies, suggesting that earlier interventions for VAs ≥ 200 beats/min are likely unnecessary, leading to an overestimation of the value of ATP in primary prevention ICD recipients

True bipolar or extended bipolar left ventricular pacing is associated with better survival in cardiac resynchronization therapy patients

BackgroundLimited studies are available on the clinical significance of left ventricular (LV) lead polarity in patients undergoing cardiac resynchronization therapy (CRT), with a recent study suggesting better outcomes with LV true bipolar pacing.ObjectiveWe aimed to determine whether true bipolar LV pacing is associated with reduced mortality in a large, real‐life CRT cohort, followed by remote monitoring.MethodsWe analyzed de‐identified device data from CRT patients followed by the Boston Scientific LATITUDE remote monitoring database system. Patients with LV bipolar leads paced between the LV ring and LV tip were identified as true bipolar and those with LV bipolar leads paced between LV tip or LV ring and right ventricular (RV) coil were identified as extended bipolar. Patients with unipolar leads were identified as unipolar.ResultsOf the 59 046 patients included in the study, 2927 had unipolar pacing, 34 390 had extended bipolar pacing, and 21 729 had true bipolar pacing. LV true bipolar pacing was associated with a significant 30% lower risk of all‐cause mortality as compared to unipolar pacing (hazards ratio [HR] = 0.70, 95% CI: 0.62‐0.79, P < .001), after adjustment for age, gender, LV lead impedance, LV pacing threshold, and BIV pacing percentage <95%. Extended bipolar LV pacing was also associated with 24% lower risk of all‐cause mortality when compared to unipolar LV pacing (HR = 0.76, 95% CI: 0.68‐0.85; P < .001). However, there were no differences in outcomes between true bipolar and extended bipolar LV pacing (HR = 0.97, 95% CI: 0.93‐1.01; P = .198).ConclusionTrue bipolar or extended bipolar LV pacing is associated with a lower risk of mortality in CRT patients as compared to unipolar LV pacing.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154901/1/pace13889_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154901/2/pace13889.pd

Direct comparison of steroid and non-steroid eluting small surface pacing leads: Randomized, multicenter clinical trial

Background: The aim of the study was to evaluate the effi cacy and safety of small surfacesteroid-eluting atrial and ventricular pacing leads in comparison to non-steroid leads usingremote monitoring system (Biotronik Home Monitoring®).Methods: In this randomized multicenter prospective trial, SIELLO T steroid-eluting ventricularleads (n = 42) were compared to BPPU T non-steroid leads (n = 46) and SIELLOJT steroid-eluting atrial leads (n = 24) to BPPU JT non-steroid leads (n = 27) (Biotronik,Berlin, Germany) in pacemaker devices with remote monitoring capabilities. Lead parameterswere evaluated during implantation, at 1-week and 1, 3, 6-month outpatient follow-up. Remotemonitoring data were collected weekly.Results: Atrial and ventricular steroid-eluting leads had stable sensing and impedance ascompared to non-steroid leads at implantation and during follow-up. Patients with non-steroidatrial leads had signifi cantly higher threshold compared to steroid leads at 1-week and at1, 3, 6-month follow-up with a peak at 1-month (1-month 1.4 ± 0.6 vs. 0.7 ± 0.3 V at 0.4 ms,p &lt; 0.001; 6-month 0.3 ± 0.5 vs. 0.2 ± 0.3 V at 0.4 ms, p = 0.002). Patients with non-steroidventricular leads had signifi cantly higher threshold compared to steroid leads at 1, 3, 6-month(6-month 1.0 ± 0.3 vs. 0.6 ± 0.2 V at 0.4 ms, p &lt; 0.001). Remote monitoring confi rmed consistentresults. During the study, 3 patients died of non-lead-related death. Lead repositioningwas necessary in 2 atrial, 2 ventricular steroid leads and in 1 ventricular non-steroid lead.Conclusions: Atrial and ventricular pacemaker leads with steroid showed signifi cantly lowerpacing threshold compared to non-steroid leads, confi rmed by remote monitoring

Insulin resistance predicts the risk for recurrent coronary events in post-infarction patients

Background: We investigated the risk for recurrent coronary events associated with insulin resistance in post-infarction patients from the Thrombogenic Factors and Recurrent Coronary Events (THROMBO) study. Methods: The association between insulin resistance expressed by Homeostatic Model As­sessment 2 for Insulin Resistance (HOMA2-IR) and the risk for recurrent coronary events was investigated in a cohort of 1,032 patients evaluated 2 months after myocardial infarction (MI) with a follow-up of 26 months. The endpoint for the study was recurrent coronary event defined as cardiac death, nonfatal MI, or unstable angina, whichever occurred first. We used time dependent survival analysis and Cox proportional hazards regression method to determine the association between HOMA2 categorized as high &gt; 75th percentile and endpoints after adjustment for relevant clinical covariates and series of thrombogenic and dyslipogenic factors. Results: High HOMA2-IR defined as in fourth quartile (≥ 2.4) was associated with increased risk for recurrent coronary events (HR 1.44; CI 1.03–2.01; p = 0.03) after adjustment for the clinical covariates: age, gender, diabetes, prior MI, pulmonary congestion, coronary artery bypass grafting and percutaneous transluminal coronary angioplasty. The highest risk of cardiac events was observed in non-obese patients (body mass index [BMI] ≤ 30 kg/m2) with high HOMA2-IR (HR 1.5; CI 1.02–2.22; p = 0.038). The plasma level of plasminogen activa­tor inhibitor-1 was associated with higher risk for recurrent coronary events in patients with insulin resistance (HR 1.79; CI 1.05–3.03; p = 0.03, interaction p = 0.018). Conclusions: In conclusion, insulin resistance predicts recurrence of coronary events in post-infarction population. HOMA2-IR is better than BMI in stratifying risk of recurrent coronary events

Clinical Impact, Safety, and Efficacy of Single- versus Dual-Coil ICD Leads in MADIT-CRT

BACKGROUND: Current data on efficacy, safety and impact on clinical outcome of single- versus dual-coil implantable cardioverter-defibrillator (ICD) leads are limited and contradictory. METHODS: Defibrillation threshold (DFT) at implantation and first shock efficacy were compared in patients implanted with single- versus dual-coil ICD leads in MADIT-CRT. The risk for atrial tachyarrhythmias and all-cause mortality were evaluated. Short- (< 30 days after the implantation) and long-term (throughout the entire study duration) complications were assessed. RESULTS: Patients with dual-coil ICD leads had significantly lower DFTs compared to patients with single-coil ICD leads (17.6 +/- 5.8 J vs 19.4 +/- 6.1 J, P < 0.001). First shock efficacy was similar among patients with dual and single-coil ICD leads (89.6% vs 92.3%, P = 1.00). When comparing patients with dual versus single-coil ICD leads, there was no difference in the risk of atrial tachyarrhythmias (HR = 1.57, 95% CI: 0.81-3.02, P = 0.18), or in the risk of all-cause mortality (HR = 1.10, 95% CI: 0.58-2.07, P = 0.77). Patients implanted with single- or dual-coil ICD lead had similar short and long-term complication rates (short-term HR = 0.96, 95% CI: 0.56-1.65, P = 0.88, long-term procedure-related HR = 0.99, 95% CI: 0.62-1.59, P = 1.00, long-term ICD lead related: HR = 1.2, 95% CI: 0.5-2.9, P = 0.68) during the mean follow-up of 3.3 years. CONCLUSIONS: Patients with single-coil ICD leads have slightly higher DFTs compared to those with dual-coil leads, but the efficacy, safety, and clinical impact on atrial tachyarrhythmias, and mortality is similar. Implantation of single-coil ICD leads may be favorable in most patients

Direct comparison of steroid and non-steroid eluting small surface pacing leads: Randomized, multicenter clinical trial

BACKGROUND: The aim of the study was to evaluate the effi cacy and safety of small surface steroid-eluting atrial and ventricular pacing leads in comparison to non-steroid leads using remote monitoring system (Biotronik Home Monitoring(R)). METHODS: In this randomized multicenter prospective trial, SIELLO T steroid-eluting ventricular leads (n = 42) were compared to BPPU T non-steroid leads (n = 46) and SIELLO JT steroid-eluting atrial leads (n = 24) to BPPU JT non-steroid leads (n = 27) (Biotronik, Berlin, Germany) in pacemaker devices with remote monitoring capabilities. Lead parameters were evaluated during implantation, at 1-week and 1, 3, 6-month outpatient follow-up. Remote monitoring data were collected weekly. RESULTS: Atrial and ventricular steroid-eluting leads had stable sensing and impedance as compared to non-steroid leads at implantation and during follow-up. Patients with non-steroid atrial leads had signifi cantly higher threshold compared to steroid leads at 1-week and at 1, 3, 6-month follow-up with a peak at 1-month (1-month 1.4 +/- 0.6 vs. 0.7 +/- 0.3 V at 0.4 ms, p < 0.001; 6-month 0.3 +/- 0.5 vs. 0.2 +/- 0.3 V at 0.4 ms, p = 0.002). Patients with non-steroid ventricular leads had signifi cantly higher threshold compared to steroid leads at 1, 3, 6-month (6-month 1.0 +/- 0.3 vs. 0.6 +/- 0.2 V at 0.4 ms, p < 0.001). Remote monitoring confi rmed consistent results. During the study, 3 patients died of non-lead-related death. Lead repositioning was necessary in 2 atrial, 2 ventricular steroid leads and in 1 ventricular non-steroid lead. CONCLUSIONS: Atrial and ventricular pacemaker leads with steroid showed signifi cantly lower pacing threshold compared to non-steroid leads, confi rmed by remote monitoring

Impact of non-cardiovascular disease burden on thirty-day hospital readmission in heart failure patients

Background: Little is known about the impact of non-cardiovascular disease (CVD) burden on 30- -day readmission in heart failure (HF) patients. The aim of the study was to assess the role of non-CVD burden on 30-day readmission in HF patients. \ Methods: We analyzed the effect of non-CVD burden by frequency of ICD-9 code categories on readmis­sions of patients discharged with a primary diagnosis of HF. We first modeled the probability of readmis­sion within 30 days as a function of demographic and clinical covariates in a randomly selected training dataset of the total cohort. Variable selection was carried out using a bootstrap LASSO procedure with 1000 bootstrap samples, the final model was tested on a validation dataset. Adjusted odds ratios and confidence intervals were reported in the validation dataset. Results: There were a total of 6228 HF hospitalizations, 1523 (24%) with readmission within 30 days of discharge. The strongest predictor for 30-day readmissions was any hospital admission in the prior year (p &lt; 0.001). Cardiovascular risk factors did not enter the final model. However, digestive system diseases increased the risk for readmission by 17% for each diagnosis (p = 0.046), while respiratory diseases and genitourinary diseases showed a trend toward a higher risk of readmission (p = 0.07 and p = 0.09, respectively). Non-CVDs out-competed cardiovascular covariates previously reported to predict readmission. Conclusions: In patients with HF hospitalization, prior admissions predicted 30-day readmission. Diseases of the digestive system also increase 30-day readmission rates. Assessment of non-CVD burden in HF patients could serve as an important risk marker for 30-day readmissions