All Elderly Patients Who Fall Should Have a 24-hour ECG

1. All Elderly Patients Who Fall Should Have a 24-hour ECG • Jennifer Inglis • Geriatric Medicine Training Day • 27th February 2007

2. The history of the ECG • Augustus Waller – published first human ECG 1887 • Willem Einthoven – created PQRST system 1895, described ECG features of CV disorders

3. 24-hour ECG • Invented by Dr. Norman J. Holter 1949 • Initially contained within a 75 pound backpack • Now a lot more portable… • …but is it helpful in investigating falls in the elderly population?

4. Some evidence • 24-hour ambulatory electrocardiographic monitoring is unhelpful in the investigation of older persons with recurrent falls • Davison J, Brady S, Kenny RA • Age and Ageing 2005; 34: 382-6 • Prospective case-control study

5. Methods • Recruited patients age >64 presenting to A&E with fall, having sustained an additional fall in previous year • Exclusions – MMSE<24 or >1 previous syncopal episode or medical explanation for fall • Controls matched for age and sex, no falls in 3 years or any previous syncope

6. Methods • Both groups fitted with 24-hour monitors • Instructed in using a symptom diary • Type and duration of arrhythmia recorded • major abnormalities e.g. VT, pauses, HR<30, Mobitz type II or complete heart block • minor abnormalities e.g. multiple VEs, paroxysmal SVT, HR 30-39, Mobitz type I, PAF/flutter • Symptoms and arrhythmias compared

7. Results - symptoms

9. Summary of findings • No significant difference between groups in prevalence of major or minor ECG abnormalities, or symptoms during recording • Multiple abnormalities present in older people whether or not they have fallen • 24-hour ECGs not helpful in investigation of recurrent falls

10. Limitations • Study not powered for small difference in abnormalities observed • Fallers were older and more likely to have hypertension and diabetes • Patients with more than one syncopal episode were excluded • Falls of any nature included… So what is our definition of a fall?

11. Definition of a Fall • “A fall is an event whereby an individual comes to rest on the ground or another lower level with or without loss of consciousness” Oxford Textbook of Geriatric Medicine • May be accidental, syncopal, drop attack, epileptic, metabolic, psychogenic (although how easy is it to tell?)

12. All elderly patients with syncope should have a 24-hour ECG Jennifer Inglis Geriatric Medicine Training Day 27th February 2007

13. Some useful questions • What causes syncope in the elderly? • Why is it important to determine the cause? • Which of these causes may be detected by a 24-hour ECG? • What is the diagnostic yield of a 24-hour ECG?

14. Neurally-mediated vasovagal carotid sinus syncope situational syncope Orthostatic hypotension autonomic failure drug-induced volume depletion Causes of syncope in the elderly

15. Cardiac arrhythmia sinus node dysfunction AV conduction system disease paroxysmal SVT/VT inherited syndromes implanted device malfunction drug-induced Structural cardiac or cardiopulmonary disease valvular disease MI/ischaemia HOCM myxoma acute aortic dissection pericardial disease PE or pulmonary hypertension Causes of syncope in the elderly

16. Causes of syncope • Neurally-mediated 56% • Cardiac syncope 14% • Arrhythmia 11% • Neurological and psychiatric 9% • >1 possible attributable cause 33% • Beware attributable and associated diagnoses

17. Framingham data • Patients with syncope of any cause have a 1.31 increased risk of death • Patients with cardiac syncope have highest risk of • death from any cause– hazard ratio 2.1 • cardiovascular event – hazard ratio 2.66

18. 24-hour tapes • Non-invasive • Safe • Low cost (approx. £70 per tape) • Beat to beat acquisition • High fidelity

19. However… • There may be intolerance to adhesive, or electrodes may become detached during recording • Symptoms may not recur during recording • Incidental abnormalities may be detected, unrelated to the fall

20. Diagnostic yield • Results from studies vary widely • For 24-hour tapes of patients with syncope or dizziness, arrhythmias in 4-64% • Rhythm-symptom correlation in 4% • 15% had symptoms but no arrhythmia (helpful in its own way) • So yield is low, making cost per diagnosis higher (NB yield from history and exam)

21. So which patients should have a 24-hour ECG? • Patients with clinical or ECG features to suggest arrhythmic syncope AND • Frequent syncopes (or pre-syncopes) - more than once per week

22. Clinical features of cardiac syncope • Syncope preceded by palpitation • Syncope occurring during exertion, or while supine • Family history of sudden death • Evidence of structural heart disease

23. ECG abnormalities suggesting arrhythmic syncope • Bifascicular block • Intraventricular conduction abnormalities • Mobitz type I AV block • HR <50 bpm, sinus pause >3s • Pre-excited QRS complexes • Prolonged QT interval • RBBB with ST elevation in leads V1-3 • Changes of arrhythmogenic RV dysplasia (!) • Q waves suggesting MI

24. Other considerations • Bass et al (1990) found that there is an increase in yield with 48-hour monitoring in comparison with a 24-hour tape • Consider role for implantable loop recorders – up to 24 months battery life, symptom/ECG correlation 88% at 6 months – more cost effective than 24-hour ECG

25. In summary • Not all elderly patients who fall should have a 24-hour ECG • Not all elderly patients with syncope should have a 24-hour ECG • Consider 24-48 hour ECG or implantable loop recorder if high suspicion of cardiac syncope as per history, examination and 12 lead ECG findings

26. Discussion points • Do we order too many 24-hour ECGs? • If so, how can we change our practice? • Do we miss important diagnoses by relying on a normal result? • Do we over-treat patients with asymptomatic ECG abnormalities? • Do we consider requesting implantable loop recorders where appropriate?