Chronic Heart Failure: What, why and how to monitor in the home

1. Chronic Heart Failure:What, why and how to monitor in the home • Sean Collins, PT, ScD • Chair & Associate Professor, Physical Therapy • Associate Professor, Biomedical Engineering • Director, Human Assessment Lab Learning with Purpose Learning with Purpose

2. What is the problem? Hospital readmit rates following discharge with CHF • 25% readmissions after 1 month • 50% readmissions after 6 months • Unplanned readmissions account for nearly 15-20% of total Medicare expenditure on acute hospital care (“frequent flyers” - - - “S/he will be back in a week.....” • 1/2 to 2/3 appear to be associated with preventable factors (poor planning, non adherence to diet / meds, inadequate social support, delays in seeking treatment) Desai, A. S. (2012).Circulation, 125(6), 828–836. Learning with Purpose

3. What, why and how to monitor • What to monitor : Stability (Broadly defined) • Why: Instability leads to admission (readmission) • How: The right information, at the right time, to make the right decisions…… • AND – teaching the patient to think & act using the same approach

4. Examination – Evaluation Cycle Patient: State/Trait Examination: Collect information Intervention Evaluation: Integrate information into action

5. What, why and how to monitor Desai, A. S. (2012).Circulation, 125(6), 828–836.

6. Important Questions Is this patient stable? • What is stability? • What are the dimensions of stability? • Core concepts • Homeostasis • Allostasis • Why is stability impaired in CHF? • Why does this relate to hospitalization / re hospitalization? • How can we assess stability? Learning with Purpose

7. Stability cycles Coordinated & Focused Muscular Activity Work Environment Bioenergetic Process O2 Glucose H2O Ventilation CV System Respiration

8. Stability cycles Learning with Purpose

9. Important Questions Underlying philosophical issues with questions of stability • Determining cause and effect • Inductive Inference • Deductive inference • Affirming the consequent / Abductive inference • Probability & Prediction Learning with Purpose

10. Probability & Prediction

11. Important Questions What needs to happen for this patient to stay stable? • What are necessary conditions for stability in any person? • Homeostasis / allostasis Learning with Purpose

12. Important Questions What needs to happen for this patient to stay stable? • What is added to these necessary conditions for a person with CHF? • How do we supplement a person with CHF for homeostasis / allostasis? Learning with Purpose

13. Important Questions What needs to happen for this patient to stay stable? • Does this particular patient meet these conditions? Learning with Purpose

14. Important Questions What needs to happen for this patient to stay stable? • Are there reasons to believe they may have problems meeting these conditions in the future? Learning with Purpose

15. What, Why, How? What is needed? Why? How? • What? • ‘….availability of an accurate and responsive measure of volume status is critical.’ • Why? • ‘Changes in filling pressures are often apparent several weeks before symptoms worsen.’ (Desai, 2012) • How? • Weight: < 50% of patients gain more than 2 lbs (0.9 kg) prior to decompensation; rapid weight gain is a specific but not a sensitive predictor Learning with Purpose

16. What can be done? Why and how? • Dyspnea, Orthopnea • Pulmonary Rales • Peripheral edema • JVD • S3 Gallop • BP response to valsalva • Hypo responsive blood pressure • Heart rate variability Learning with Purpose

17. What can be done? Dyspnea, Orthopnea, Peripheral Edema, Rales • Dyspnea • ~50% specificity and sensitivity • Edema • ~80% specificity, 36% sensitivity • Orthopnea • ~88% specificity, 50 sensitivity • Rales • ~70% specificity and sensitivity Learning with Purpose

18. What can be done? JVD • Related to filling pressures • Need to assess from the beginning of care and correlate with other signs / symptoms • JVD specificity 94%, sensitivity 39% Learning with Purpose

19. What can be done? S3 Gallop • S3 is suggestive of elevated PCWP • specificity 99%, sensitivity 20% Learning with Purpose

20. What can be done? Hypo responsive blood pressure to activity • Expect ~ 10 (+/-2) mm Hg increase per MET increase in workload • Hypo responsive BP is an indicator of poor CO response • Drops in BP to workload is a stronger indicator of ineffective CO response • Need to assess in context – based on a history of knowing how this person responds Learning with Purpose

21. What can be done? BP response to valsalva • Find Systolic BP (SBP) • Raise cuff pressure to 15 mmHg above SBP during normal breathing • Have patient perform VM (to about 30 mm Hg if using a manometer) for 10 seconds while auscultating the brachial artery • A: if hear Korotkoff sounds, then they disappear and reappear • B: if hear sounds, then disappear and do not reappear • C: If hear sounds and they do not disappear until after VM is released Learning with Purpose

22. What can be done? BP response to valsalva • Zema et al (1980, 1984) have found specificity 80% and sensitivity 80% for non Sinusoidal responses for elevated LVEDP • Weilenmann et al (2002) found BP response to valsalva to be related to PCWP (R^2 = .75); and a specificity 95% and sensitivity 91% for identifying a PCWP > 15 mm Hg Learning with Purpose

23. What can be done? Heart rate variability • Adamson et al (2004) showed that reductions in HRV (SDANN) and activity tended to precede readmission by up to 3 weeks with a specificity and sensitivity of 70% • Difficult to discern whether this could as easily be assessed with physical activity monitors as there is a strong relationship between HRV and activity Learning with Purpose

24. What else can be done? On the horizon…… • Smaller non invasive sensors • Implantable sensors • Multimodal sensor / data integration • Human Assessment Lab at UMass Lowell • Acoustic cardiology • Physical activity • Heart rate variability • Pulse transit time Learning with Purpose

25. Thank you! • Questions? • These slides are available at: • http://cardiopulmonarypt.wiki.uml.edu • Follow the link to the left to “Miscellaneous Presentations” Learning with Purpose