Next-generation Mobile Cardiac Telemetry: Clinical Value of Combining Electrocardiographic and Physiologic Parameters.

The ZOLL Arrhythmia Monitoring System, a mobile cardiac telemetry (MCT) device from ZOLL Corporation (Chelmsford, MA, USA), records single-channel electrocardiogram (ECG) signals, heart rate, activity, respiratory rate, and posture. Comprehensive reporting from these multiple biometrics may provide a global evaluation of arrhythmic or other cardiovascular risks in individual patients and insights into the patient's overall wellness and health status. The objective of the study was to evaluate the physician-perceived utility of adding biometric data to the traditional ECG-only-based assessment and subject-reported symptoms. This prospective study recruited candidates for MCT. Independent event and end-of-use (EOU) reports based on ECG and biometrics data were provided to physicians. To document whether the biometric data affected treatment plan decisions or added value over the ECG-alone data, physicians completed a questionnaire for each report. Additionally, they completed the questionnaire to understand the utility of the subject wellness information provided in the EOU report. From December 2020 to July 2021, 583 patients were enrolled by 27 physicians from 18 cardiology practices in the United States. When using biometrics data compared to the ECG alone, this study found that 96% of the physicians made changes to the treatment plan that initially was based on the ECG alone. The biometrics-based changes involved 64% of all patients (n = 535), and included modifications to medications, follow-up, and lifestyle in 18%, 19%, and 63% of the subjects, respectively. In this largest MCT study conducted to date, next-generation MCT, by providing multiple biometric parameters along with ECG data, improves physicians' ability to make patient management decisions. This added functionality and clarity may replace traditional "ECG with diary"-based monitoring.

CRT Efficacy in "Mid-Range" QRS Duration Among Asians Contrasted to Non-Asians, and Influence of Height.

OBJECTIVES: The purpose of this study was to test the hypotheses that cardiac resynchronization therapy (CRT) efficacy differed among Asians compared with non-Asian populations, differed between QRS duration (QRSd) ranges 120-149 and ≥150 ms, and was influenced by height in the multinational ADVANCE CRT trial. BACKGROUND: CRT guidelines, derived from trials among U.S./European patients, assign weaker recommendations to those with midrange QRSd (QRSd <150 ms). Patient height may modulate CRT efficacy. Together, these may affect CRT prescription and efficacy in Asia. METHODS: CRT response was assessed using the Clinical Composite Score 6 months postimplant (n = 934). Heart failure events and cardiac deaths were reported until 12 months. Asian and non-Asian patients were compared overall, by QRSd <150 ms (Asian n = 71 vs non-Asian n = 248), and QRSd ≥150 ms (Asian n = 180 vs non-Asian n = 435) and by height. RESULTS: Asians comprised 27% (251 of 934) of the primary study population. More Asians had QRSd ≥150 ms (72% [180 of 251] vs 64% [435 of 683] in non-Asian patients; P = 0.022). Overall CRT response was better in Asians vs non-Asians (Clinical Composite Score 85% vs 65%; P <0.001), and following QRSd dichotomization (QRSd <150 ms: 80% vs 59%; P <0.001; QRS ≥150 ms: 86% vs 69%; P < 0.001). HF events and cardiac deaths were fewer in Asians irrespective of QRSd (P < 0.001). Stepwise multivariable analysis indicated that in group QRSd <150 ms, nonischemic cardiomyopathy, number of other comorbidities (0-1 vs ≥4), and atrial fibrillation influenced CRT response. The trend favoring Asian race (OR: 1.46; 95% CI: 0.72-2.95) was eliminated (OR: 1.00; 95% CI: 0.47-2.11) when height or QRSd/height were included (QRSd/height P = 0.006; OR: 1.64; 95% CI: 1.15-2.35). In QRSd <150 ms, probability of CRT response diminished as height increased, but increased with QRSd/height, in both Asians and non-Asians. In QRSd ≥150 ms, height or QRSd/height had minimal effect in Asians or non-Asians. CONCLUSIONS: Height modulates CRT efficacy among patients with QRSd <150 ms and contributes to high probability of benefit from CRT among Asians. CRT should be encouraged among Asian patients with midrange QRSd. (Advance Cardiac Resynchronization Therapy [CRT] Registry; NCT01805154).

The cost of non-response to cardiac resynchronization therapy: characterizing heart failure events following cardiac resynchronization therapy.

AIMS: The aim of this study is to quantify healthcare resource utilization among non-responders to cardiac resynchronization therapy (CRT-NR) by heart failure (HF) events and influence of comorbidities. METHODS AND RESULTS: The ADVANCE CRT registry (2013-2015) prospectively identified responders/CRT-NRs 6 months post-implant using the clinical composite score. Heart failure event rates and associated cost, both overall and separated for inpatient hospitalizations, office visits, emergency room visits, and observational stays, were quantified. Costs of events were imputed from payments for similar real-world encounters in subjects with CRT-D/P devices in the MarketScan™ commercial and Medicare Supplemental insurance claims databases. Effects of patient demographics and comorbidities on event rates and cost were evaluated. Of 879 US patients (age 69 ± 11 years, 29% female, ischaemic disease 52%), 310 (35%) were CRT-NR. Among CRT-NRs vs. responders, more patients developed HF (41% vs. 11%, P < 0.001), HF event rate was higher (67.0 ± 21.7 vs. 11.4 ± 3.7/100 pt-year, P < 0.001), and HF readmission within 30 days was more common [hazard ratio 7.06, 95% confidence interval (2.1-43.7)]. Inpatient hospitalization was the most common and most expensive event type in CRT-NR. Comorbid HF was increased by diabetes, hypertension, and pulmonary disorders. Over 2 years, compared to CRT responders, each CRT-NR resulted in excess cost of $6388 ($3859-$10 483) to Medicare (P = 0.015) or $10 197 ($6161-$17 394) to private insurances (P = 0.014). CONCLUSION: Healthcare expenditures associated with contemporary CRT non-response management are among the highest for any HF patient group. This illustrates an unmet need for interventions to improve HF outcomes and reduce costs among some CRT recipients.

Use of Biologic Extracellular Matrix in Two Ways to Reduce Cardiac Electronic Device Infection.

Cardiac implantable electronic device (CIED) infections are a serious complication of both initial device implants and generator change procedures, and they are associated with a wide range of presentations. Reported rates of CIED infections vary widely from 0.1% to 19.9%, but it is estimated that they occur in 0.5% of initial device implants and 1-7% of subsequent implants. It is widely accepted that the administration of local antibiotics within the pocket as well as extracellular matrices (ECMs) can be utilized to reduce the incidence of CIED infections. We describe a case where the use of an additional biological ECM scaffold sutured directly into the incision site was utilized in addition to a biological ECM pouch in order to reduce the risk of infection. We propose that biological ECM could be utilized to reinforce the incision site directly as well as ECM within the pocket to reduce the instances of CIED infections. Further investigation of the use of biological ECM to prevent infection is warranted and paramount to further decrease the number of complications associated with device implantation.

A manifesto of collaborative longitudinal cardiovascular care in heart failure.

In this document, we outline the challenges faced by patients and clinicians in heart failure, specifically centered around the needed coordination of care among the various subspecialties within cardiovascular medicine. We call for a more organized and collaborative effort among clinicians in primary care, general cardiology, electrophysiology, interventional cardiology, cardiothoracic surgery, cardiac imaging, and heart failure-all caring for mutual patients. Care is contextualized within the framework of two phases: a cardiomyopathy phase and an advanced heart failure phase, each of which lends to different considerations in therapy. Ultimately multidisciplinary coordinated care within cardiovascular medicine may lead to greater patient and clinician satisfaction as well as improved outcomes, but this remains to be investigated.

Evaluation, Management, and Outcomes of Patients Poorly Responsive to Cardiac Resynchronization Device Therapy.

BACKGROUND: "Nonresponse" to cardiac resynchronization therapy (CRT) is recognized, but definition(s) applied in practice, treatment(s), and their consequences are little known. OBJECTIVES: The authors sought to assess nonresponse in the prospective, international, ADVANCE CRT registry (Advance Cardiac Resynchronization Therapy Registry). METHODS: Each subject's response was assessed at 6 months post-implantation using site-specific definitions and compared with the independently derived clinical composite score (CCS). Treatment(s) and hospitalization(s) were tracked during the following 6 months. RESULTS: Of 1,524 subjects enrolled in 69 centers (68 ± 12 years of age, 32% female, ischemic disease 39%), 74.3% received CRT-defibrillator devices, using mainly quadripolar LV leads (75%) deployed laterally (78%). Indications for CRT were wider than past trials. Among 1,327 evaluable subjects, site-defined nonresponse was 20.0% (greater age, comorbidities, ischemic cardiomyopathy, non-left bundle branch block, and lower %CRT pacing vs. responders). Site definitions used mainly clinical criteria (echocardiography infrequently), and underestimated nonresponders by 35% compared with CCS (58% sensitivity vs. CCS). Overall, more site-defined nonresponders received treatment (55.9% vs. 38.3% of responders; p < 0.001) using medication changes and heart failure education, but device programming less frequently. Intensification of in-clinic/remote evaluations and involvement of heart failure specialists remained minimal. Remarkably, 44% of site-defined nonresponders received no additional treatment. Frequency and duration of hospitalizations, and death, among site-defined nonresponders was significantly higher than responders. CONCLUSIONS: A high incidence of CRT nonresponders persists despite good patient selection and LV lead position, but site identification methods have modest sensitivity. Following diagnosis, nonresponders are often passively managed, without specialty care, with poor outcome. ADVANCE CRT exposes a vulnerable group of heart failure patients. (Advance Cardiac Resynchronization Therapy Registry [ADVANCE CRT]; NCT01805154).

Percutaneous closure of a left atrial appendage pseudoaneurysm.

Atrial dissections and pseudoaneurysms are rare complications of cardiac surgery. The authors describe the case of a patient after mitral valve replacement who presented with a left atrial appendage pseudoaneurysm. This case represents the first known closure of an atrial pseudoaneurysm with a percutaneous septal occluder device.

Adhesive epicardial corticosteroids prevent postoperative atrial fibrillation.

BACKGROUND: Postoperative atrial fibrillation remains a common cause of morbidity. Although epicardial drug delivery can increase efficacy and reduce side effects, it is impractical for postoperative atrial fibrillation because pericardial bleeding/effusion and drainage cause rapid drug elimination. Fibrin glue sprayed on the epicardium is vigorously adherent, allowing an admixed drug to remain in contact with the heart. The purpose of the present study was to evaluate a novel corticosteroid-fibrin glue mixture applied to the atrial epicardium at the time of surgery for prevention of postoperative atrial tachyarrhythmias. METHODS AND RESULTS: Talc was instilled into the pericardium in 15 dogs to simulate postoperative inflammation. Pacemakers were implanted to monitor arrhythmias. A mixture of triamcinolone and fibrin glue (Tisseel) was sprayed onto the atria of the treatment animals (n=9), whereas control animals (n=6) received Tisseel or nothing. After 1 week, pacemaker interrogation quantified postoperative atrial tachyarrhythmias (atrial rate >200 bpm) burden. Excised hearts underwent histological examination and tensile strength testing. postoperative atrial tachyarrhythmias occurred in 100% of control animals but only 33% of treatment animals (P=0.027). The median time (25th percentile, 75th percentile) in tachycardia was 5.5 hours (2.7, 12.6) per day in the control group, compared with 0 hours (0, 0.2) in the treatment group (P=0.001). Severe inflammation was present in 6 of 6 control animals and 1 of 9 treatment animals (P=0.001). The tensile strength of a healing left atriotomy was not significantly different between groups. Steroid levels at the time the animals were killed were very low (median of 0.22 µg/dL [0.18, 0.23]). CONCLUSIONS: A mixture of triamcinolone and fibrin glue sprayed onto the atria reduced postoperative atrial tachyarrhythmias and reduced inflammatory cell infiltration. There was no change in the tensile strength of a healing atriotomy and plasma steroid levels were low. Clinical trials of this approach are warranted.

Stretch-activated receptors mediate cardiac memory.

BACKGROUND: Cardiac memory refers to long-lasting T-wave changes that follow an episode of altered ventricular activation sequence. Memory-induced alterations in repolarizing ion channel activity have been characterized. However, the mechanism by which changes in activation sequence produce these effects is unknown. We hypothesized that cardiac memory is mediated by the response of stretch-activated receptors (SARs) to a change in mechanical activation sequence. METHODS: In anesthetized, closed-chest dogs, coronary sinus leads were used to pace the posterolateral left ventricle (LV) continuously for 1 hour at a rate of 120 bpm. The surface vectorcardiogram was used to quantify cardiac memory by measuring T-wave displacement after pacing. Streptomycin, which has been shown to block SARs, was given at a dose of 4 g intramuscularly 1 hour before experimental LV pacing sessions. T-wave displacement after control sessions of LV pacing in the absence of drug (n = 12) was compared to that produced by pacing after streptomycin administration (n = 10 sessions). RESULTS: There was a distinct and consistent cardiac memory seen after 1 hour of LV pacing under control conditions, with T-wave displacement of 1.28 +/- 0.43 mV (P < 0.001 vs baseline). Pretreatment with streptomycin had no direct effect on the electrocardiogram or hemodynamics, but decreased pacing-induced T-wave displacement to 0.50 +/- 0.28 mV (P < 0.001 vs control sessions). CONCLUSIONS: Streptomycin, a SAR blocker, dramatically attenuated the development of cardiac memory following epicardial pacing. These data suggest that SARs are a critical link between mechanical sequence of activation and regional modulation of action potential duration that is responsible for cardiac memory.

Ascending aortic hemodynamics and one-year clinical events following percutaneous coronary intervention.

Increased pulse pressure has been shown to predict mortality and major adverse cardiac events (MACE) in large cohorts of ambulatory patients. There have been reports suggesting worsened outcome following percutaneous coronary balloon angioplasty in patients with increased pulse pressure. We reviewed 434 patients undergoing percutaneous coronary stenting to assess for clinical outcomes as a function of pulse pressure (PP) and pulse pressure fraction (PPf). At 1 year, MACE was identified in 17.9% of subjects. There was no statistically significant difference in PP or PPf in those subjects with and without death, myocardial infarction or revascularization. Although previously reported to have correlation with risk for revascularization following balloon angioplasty, aortic pulse pressure at the time of percutaneous coronary intervention with stenting does not predict the risk for cardiac events at 1 year.