Implantable Sensors for Heart Failure

“To be accepted as a paradigm, a theory must seem better than its competitors, but it need not, and in fact never does, explain all the facts with which it can be confronted.” Thomas Kuhn, The Structure of Scientific Revolutions ### Heard on Rounds “A 57-year-old patient with a history of heart failure states that she began experiencing worsening shortness of breath 4 days prior to admission, with lower extremity edema developing 1 day prior to admission. She is compliant with her medications, though has had similar admissions previously. She states that her weight at home increased by “a couple of pounds” 2 days ago and that she increased her diuretic dose but her symptoms worsened. She says that she generally adheres to her low salt diet, but admits to eating pretzels 5 days ago. The physical examination showed BP 136/84, HR 94, weight 3 lbs above baseline, elevated JVP, basilar rales, and 1+ pedal edema.” As the intern finishes the presentation, the Senior expresses surprise that the patient's weight had increased only 3 pounds, and comments about salt and volume overload leading to acute decompensated heart failure (ADHF). The Attending adds that recent data reveal that many patients presenting with ADHF have minimal or no weight gain, but that there is no clear mechanism to explain this phenomenon. They set in place plans for diuresis, increasing vasodilators, and further patient education. On the surface, there is nothing remarkable about this case, and the usual approaches to treat this entity have remained remarkably consistent since the advent of loop diuretics over 50 years ago: salt restriction, patient education, uptitration of medications if not already at optimal doses, and diuresis. However, approximately 1 in 4 such patients are readmitted to the hospital within 30 days,1 and the disease continues to progress. It is clear …

Recent Trends in the Incidence, Treatment, and Prognosis of Patients With Heart Failure and Atrial Fibrillation (the Worcester Heart Failure Study)

Background: Trends for acute decompensated heart failure (ADHF) hospitalizations based on the primary discharge ICD codes have declined in the U.S. However, HF ICD codes are increasingly found in non-primary positions. Validation data are needed to estimate the frequency of ADHF hospitalizations. Methods: The ARIC Study conducts surveillance for hospitalized ADHF in four U.S. communities for age ≥ 55 years since 2005. Hospital records are sampled, abstracted, and classified as ADHF or not by an expert physician panel. Analyses were stratified on code groups (a) 428.xx in primary-position, (b) 428.xx in non-primary position, and (c) other sampled HF ICD code (398, 402, 404, 415, 416, 425, 518, 786) in any position. We calculated ADHF probability in each group overall (positive predictive value, PPV), and by using regression models. We estimated the nationwide trends of ADHF hospitalizations from the National Inpatient Sample (NIS), a 20% probability sample of U.S. community hospitals, by applying the calibration factors derived in the ARIC study. Results: In ARIC surveillance 42% of eligible hospitalizations (n=12,450 charts) validated as ADHF. NIS data included 9 million eligible hospitalizations during 1999-2010. The estimated numbers of US ADHF hospitalization in 2010 among Americans ≥ 55 years old was 1.8 (SE 0.02) million as compared to 0.8 (SE 0.002) million with 428.xx in the primary position ( Figure ). The estimated ADHF hospitalizations in the U.S. increased from 1.6 million in 1999 to 1.9 million in 2006, and then decreased to 1.8 million in 2010 (average annual increase of 1%, p-trend <0.01). Estimated ADHF based on regression models for each of the three code groups gave similar results. The temporal increase was steeper among men and in age category 55-64 years than older ages. Conclusions: Estimated frequency of ADHF hospitalizations by ARIC validation criteria is about two times higher than ICD 428 in primary position; with an overall increasing vs. declining trend over the last decade.

Background Several studies have observed increased incidence of myocardial infarctions during Christmas and national holidays. Emotional stress, overindulgence in food and alcohol have been suggested as potential underlying mechanisms. Monitoring of thoracic impedance (TI) by cardiac implantable electronic devices (CIED) has been proposed as a tool for detection of fluid accumulation. We aimed to assess the relationship between TI and national holidays in patients treated with CIED with and without reduced left ventricular ejection fraction (LVEF). Method Consecutive patients with CIED capable of TI monitoring enrolled in the remote monitoring program at a tertiary care hospital in Sweden were screened. Full disclosure remote CIED monitoring database containing daily measurements of TI and device therapy delivery was accessed as the source of information for this retrospective cohort study. Patients were included if they had the monitoring data for at least one holiday (Christmas, New Year or Midsummer) between June 2015 and January 2020. TI during the holiday was compared with baseline values, defined as a mean value of three days preceding Christmas Eve and Midsummer. Clinical characteristics, LVEF, medical treatment and possible contact with healthcare during the holidays or the following week were obtained from medical records. A linear mixed model was used since dependent observations existed. Result In total, 96 patients (82 % men, age 69±10 years, 92 % ICD, 78 % CRT, 72 % with LVEF<40%) were included, which provided data for 255 patient-holidays. TI decreased by mean 1.3 Ohm (95% CI -1.9 to -0.6, p< 0.001) on the Christmas Day, 0.6 Ohm (95 % CI -1.4 to 0.1, p = 0.08) on New Years Day and 1.0 Ohm (95 %CI -1.7 to -0.3, p=0.005) on Midsummer Day. These TI changes were not related to age and did not differ between men and women. Holiday-related TI drop was observed regardless of LVEF: mean decrease on Christmas Day 1,1 vs 1,4 Ohm, New Years Day 0,2 vs 0,4 Ohm and Midsummer Day 1,2 vs 1,0 Ohm for LVEF <40% and >40% respectively. By the third day after a holiday, TI had reached the baseline level. Only one ventricular tachycardia event requiring shock therapy and hospital admission was documented. No other patients were seeking care during the holidays or the days afterwards. Conclusion A significant transient decrease in thoracic impedance was evident during Christmas Day and Midsummer Day in CIED treated patients with reduced and preserved LVEF. These holidays are therefore associated with both decrease in thoracic impedance and incidence of myocardial infarction and it is possible that decrease in thoracic impedance could contribute to the increased incidence of myocardial infarction during holidays.

Remote Wireless Telemonitoring Combined with Health Coaching (Tele-HC) to Lower Readmission Rates for Patients with Acute Decompensated Heart Failure

Background According to new recommendations for the management of acute decompensated heart failure (ADHF) in 2015, intravenous vasodilator therapy might be given as an early therapy when systolic blood pressure is normal to high (≥110mmHg). Only 29% of patients with ADHF are treated with vasodilators without medical contraindication. Objective To evaluate the effect of the systematic use of ISDN on ADHF without contraindication especially on rehospitalization rate. Settings The 600-bed hospital (Centre Hospitalier de l'Ouest Vosgien, Neufchâteau, France). Methods This is a retrospective study with data analysed from medical records. Patients with ADHF episodes and hospitalization in the cardiology department or intensive care unit (ICU) between November 2013 and December 2015 were included resulting in 199 hospitalizations in the analysis (37 were treated by ISDN, and 162 were not). Main outcome measure Effects of ISDN on 180-day hospital readmission for ADHF or acute myocardial infarction (AMI), in-hospital mortality, length of stay, number of ICU admissions, and ICU length of stay. Results Patients who received ISDN required more ICU admissions than the other patients (54.1 vs 33.3%, p=0.02). Nevertheless 180-day hospital readmission was lower for patients who were receiving ISDN (8.1 vs 22.8%, p=0.04). ISDN did not influence other clinical outcomes tested. Conclusion ISDN may minimize or prevent the consequences of altered haemodynamics. Lower rehospitalization rate with ISDN was seen in this study.

The higher incidence of myocardial infarction (MI) during national holidays could be caused by overindulgence of food and beverages, potentially straining the heart of vulnerable individuals. Monitoring decreased thoracic impedance by cardiac implantable electronic devices (CIED) can be used for detection of fluid accumulation. We aimed to assess the relationship between cardiac metrics and national holidays in patients with CIED. Patients with CIED-based impedance monitoring at a tertiary care hospital in Sweden were screened. Patients were included if they had data for at least one holiday (Christmas, New Year, or Midsummer) between June 2015 and January 2020. Thoracic impedance, heart rate variability, and activity during the holiday were compared with baseline values, defined as the average of 3 days preceding Christmas and Midsummer. Clinical characteristics were obtained from medical records. In total, 96 patients (82% men, age 69 ± 10 years, 92% ICD, 78% CRT, 72% with LVEF < 40%) were included, which provided data for 649 patient-holidays. During Christmas Day, New Year's Day, and Midsummer Day combined, impedance decreased by a mean of 1.1 Ohm [95% CI 0.7-1.6, P < 0.001], heart rate variability decreased by a mean of 8.0 ms [4.9-11.2, P > 0.001] and daily activity by a mean of 40 min [35-45, P < 0.001]. One ventricular tachycardia event requiring shock therapy was documented during the holiday. A transient decrease in thoracic impedance, heart rate variability, and physical activity was observed during national holidays, potentially contributing to the higher incidence of MI during holidays.

Introduction: Hospitalization for acute decompensated heart failure (ADHF) remains a major source of morbidity and mortality. While previous studies have shown outpatient intravenous (IV) diuretic therapy to be safe and cost-effective, there have been no randomized controlled trials to evaluate the utilization of continued outpatient IV furosemide diuretic maintenance treatment in patients with HF following hospitalization for ADHF. Hypothesis: We hypothesized that 30-day hospital readmission from ADHF would be lower with routine, standardized outpatient IV diuretic treatment along with a comprehensive HF care approach vs standard treatment. Methods: In a single center, prospective, randomized, double-blind study, 100 patients were randomized to receive standard of care (Group 1), IV placebo infusion (Group 2), or IV furosemide infusion (Group 3) over 3 hours, biweekly for a one-month period following hospitalization for ADHF. Patients in Groups 2 and 3 also received a comprehensive HF care protocol including bi-weekly clinic visits for dose-adjusted IV-diuretics, medication adjustment, laboratory, weight, and blood pressure-monitoring, and education during infusion visits. Echocardiography, Kansas City Cardiomyopathy Questionnaire (KCCQ) and depression questionnaires were performed at baseline and 30-day follow-up. The primary outcome was 30-day re-hospitalization for ADHF. Results: Overall, a total of 94 patients were included in the study (mean age 64 years, 56% males, 69% African American, 70% HF reduced ejection fraction). There were a total of 14 (15%) readmissions for ADHF at 30 days, 6 (17.1%) in Group 1, 7 (22.6%) in Group 2, and 1 (3.7%) in Group 3 (overall p=0.11; p=0.037 comparing Group 2 and Group 3). Patients receiving IV furosemide infusion experienced significantly greater urine output and weight loss compared to those receiving placebo without any significant increase creatinine and no significant between group differences in echocardiography parameters, KCCQ or depression scores. Conclusions: The use of a standardized protocol of outpatient IV furosemide infusion for a one-month period following hospitalization for ADHF was found to be safe and efficacious in reducing 30-day re-hospitalization.

Patterns Of Renin-Angiotensin-Aldosterone-System Inhibitor Interruption In Patients Hospitalized For Acute Decompensated Heart Failure

ObjectivesTo examine the association of a high C-reactive protein (CRP) level at discharge from an acute decompensated heart failure (ADHF) hospitalisation with the 1-year clinical outcomes.DesignA post-hoc subanalysis of a...

Background: Recent study demonstrated paradoxical relationship between body mass Index (BMI) and all cause mortality in patients with acute decompensated heart Failure (ADHF), where higher BMI was associated with decreased mortality. We sought to test whether this relationship exists between BMI and ADHF readmissions Methods: Consecutive patients presented to the emergency department from March 2014 to July 2015 with the diagnosis of ADHF were analyzed in a retrospective cohort study. Cohort was grouped in to prespecified BMI categories; normal weight (BMI &lt;26 Kg/m2 ), Over weight (BMI 25-30 Kg/m2 ) and Obese (BMI &gt;30 Kg/m2 and above). Primary endpoints were incidence of 30 day ADHF readmission and time to first ADHF readmission from the index hospitalization. Patients with end stage COPD on home O2, cirrhosis and end stage renal failure on dialysis were excluded. Unplanned hospitalizations due to other cause than ADHF were excluded. ADHF hospitalizations were adjudicated by an independent blinded clinician Results: Cohort (N=188) consisted 51(27.1%) normal weight, 61 (32.4%) over weight and 76 (40.4%) obese patients. Females were 63% (N=119), patients with heart failure with preserved ejection fraction were 47% (N=90), Obese [BMI 31(28-38) Kg/m2; Median (IQR)] patients were younger (median age; 77 years vs 83 years; P=0.002), whereas other covariates were similar between groups. In median follow up of 1.2 years, total 30 day ADHF readmissions were 32 and total ADHF admissions were 214. Incidence of both 30 day and total ADHF readmissions were similar in all 3 BMI categories; ANOVA P=0.18 (30 day ADHF readmissions) and P= 0.62 (total ADHF readmissions). Obesity was neither associated with risk for 30 day readmission; OR=0.64 (CI: 0.20 - 2.0; P= 0.45) nor with the time to first ADHF readmission from the index hospitalization; log rank P=0.5 (Figure 1) Conclusions: Higher BMI is not protective against ADHF readmissions in patients with ADHF. Further studies are needed in larger data sets to validate our findings.

242 - Thoracic Impedance & Pulmonary Artery Pressure Monitoring in Prevention of Heart Failure Hospitalizations

Background: Heart failure (HF) patients with aortic stenosis (AS) constitute a high-risk population posing diagnostic and therapeutic challenges. Few studies have characterized the burden of AS in patients admitted with acute decompensated HF (ADHF), stratified by ejection fraction (EF). Methods: The Atherosclerosis Risk in Communities study conducted community-based surveillance of a random sample of ADHF hospitalizations for residents ≥55 years of age in four US communities. ADHF cases were subclassified as having reduced (HFrEF) or preserved (HFpEF) EF using a 50% cutoff. AS severity was determined from echocardiogram reports obtained during abstracted hospitalizations. Odds of moderate or severe AS in patients with varying sex and race, and odds of all-cause 1-year mortality in those with higher AS severity were estimated using multivariable logistic regression. Results: From 2005-2014, there were 14,289 weighted ADHF hospitalizations of whom 7,357 had HFrEF (45.0% female, 36.6% black) and 6,932 HFpEF (62.9% female, 26.5% black). The prevalence of moderate or severe AS was 5.67% in HFrEF and 9.43% in HFpEF. Patients with higher AS severity were older than those with none or mild AS in both HFrEF ([mean age] 79.7 vs. 74.4 years, p&lt;0.0001) and HFpEF (81.7 vs. 76.3 years, p&lt;0.0001). No difference in odds of higher AS severity was detected between females and males in both HFrEF (5.49% vs. 5.81%, OR: 1.03, 95% CI: 0.83-1.27) and HFpEF (9.10% vs. 9.99%, OR: 0.89, 95% CI: 0.75-1.06). Moderate or severe AS was more likely in whites than blacks in both HFrEF (8.32% vs. 1.67%, OR: 0.23, 95% CI: 0.17-0.32) and HFpEF (11.1% vs. 6.38%, OR: 0.70, 95% CI: 0.56-0.88). Higher AS severity was independently associated with increased all-cause 1-year mortality after ADHF hospitalization in both HFrEF (44.3% vs. 30.5%, OR: 1.25, 95% CI: 1.16-1.35) and HFpEF (33.4% vs. 26.1%, OR: 1.16, 95% CI: 1.08-1.24). Conclusion: In ADHF patients with HFrEF or HFpEF, whites are more affected by AS than blacks, as are older patients when compared to their younger counterparts. Higher AS severity in ADHF patients is independently associated with all-cause mortality at 1 year after hospitalization, regardless of EF.

IN THIS ISSUE OF JAMA, 2 ARTICLES REPORT FINDINGS FROM the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) clinical trials program. Konstam et al report the overall longterm effects of tolvaptan in terms of safety and clinical outcomes for patients with worsening heart failure (HF) requiring hospitalization. Gheorghiade et al report shortterm effects of tolvaptan for acute symptom relief in these same patients, but presented as 2 trials that were based on study center assignment following completion of patient enrollment and randomization in the long-term trial. The aggregate findings demonstrate that tolvaptan relieves some symptoms associated with acute decompensated heart failure (ADHF) and has no demonstrable evidence of harm such as worsening of renal failure, but importantly, does not reduce mortality or HF-related morbidity at 1 year. In the context of ADHF, these are noteworthy findings. To date, no other therapeutic intervention has been demonstrated in large-scale randomized, placebo-controlled studies to positively influence symptoms in ADHF without generating a question of harm. Inotropes have been associated with increased mortality risk, and calcium sensitizers have been associated with increased cardiovascular mortality. Nesiritide was shown to relieve dyspnea and to reduce pulmonary congestion over the short term, but also was associated with increased intermediate-term mortality risks. Traditional vasodilator therapy relieves HF symptoms, but neither nitroglycerin nor nitroprusside has been subjected to prospective randomized controlled study, and effects on mortality are unknown. Even diuretics, which clearly relieve congestion, have uncertain effects on outcomes. Addressing the challenge of ADHF has been daunting. Acute decompensated HF accounts for more than 1 million acute hospitalizations per year in the United States at an annual cost of more than $30 billion and is associated with significant mortality. The risk of inpatient death is approximately 4% (but ranges from 2%-22%), and the risk of death/rehospitalization at 60 to 90 days after an episode of ADHF is 36%. At the core of this challenge, however, is the limited understanding of the pathophysiology of ADHF. While hemodynamic disturbances are clearly responsible for the observed signs and symptoms, plausible causative mechanisms that trigger acute decompensation, eg, ventricular injury and augmented neurohormonal activation, remain uncertain. Thus, therapy for ADHF is relegated to correcting perturbed hemodynamics. Comparison is made with the evolution of therapy for chronic HF—targeting hemodynamic abnormalities did not yield meaningful clinical benefits, but elucidation of relevant pathophysiological mechanisms followed by appropriately focused interventions in largescale trials resulted in salutary improvements. A similar approach is needed for ADHF. Another challenge of ADHF involves clinical trial design and construct. The studies to date have been small to moderate short-term hemodynamic or symptom-focused designs, constructed primarily to meet regulatory requirements. Important questions, including mechanistic hypotheses and the effect of interventions on rehospitalizations/mortality, have been inadequately studied. Trials in ADHF have also been confounded by considerable heterogeneity of the patient phenotype. Patients with ADHF are older, represent a mix of new-onset HF and decompensated chronic HF, have both reduced and preserved ejection fraction HF, have equal gender representation, and frequently have a number of important comorbidities, especially renal insufficiency. Moreover, “standard therapy” does not truly exist, as there are no evidence-based interventions proven to reduce morbidity and mortality associated with ADHF. Guidelines for ADHF have recently been put forward, but the treatment algorithms are sparse and focus on hemodynamic targets. The strategy is to relieve symptoms preferentially with diuretic use, including high-dose loop diuretics and continuous diuretic infusions (the safety of which is not known in HF), and to add vasodilator therapy (nitroglycerin or nitroprusside) if adjunctive approaches are needed. Inotropes are reserved for impending or frank shock but are otherwise dissuaded. Ultrafiltration represents at best an emerging technology with intriguing preliminary data but limited applications.

Changes in Heart Rate and Heart Rate Variability Over Time in Middle-Aged Men and Women in the General Population (from the Whitehall II Cohort Study)