3. CRT in NYHA I and II
Stretching our limits
Overdoing in false hope
4. Benefit of CRT in NYHA III and IV
(ambulatory)
• Companion trial
N Engl J Med 2004;350:2140-50.
– By one year CRT-P / CRT-D reduces death or
hospitalization for HF by 12% (ARR)
– NNT: 9 patients for 1 year to prevent 1 death or
hospitalization for HF
• CARE - HF
N Engl J Med 2005;352:1539-49.
– Total follow up 30 months
– CRT-P / CRT-D reduces death or hospitalization for HF
by 16% (ARR)
– NNT: 6 patient for 1 year to prevent 1 death or
hospitalization for HF
6. The NYHA class fallacy
• What many consider
– NYHA class I: Asymptomatic
– NYHA class II: mildly symptomatic
• But what guidelines says
– NYHA class I: Initially any class but now Class I, after
medication as necessary
– Similar for Class II
Adherence to BB, ACEI, ARB and diuretics: 97% in trial
patients
7. Trials (in NYHA I and II) which were the
basis for the guidelines
• REVERSE
• RAFT
Randomized trial of cardiac resynchronization in mildly symptomatic
heart failure patients and in asymptomatic patients with left ventricular
dysfunction and previous heart failure symptoms.
Cardiac- resynchronization therapy for mild-to-moderate heart failure.
• MADIT – CRT
J Am Coll Cardiol 2008; 52:1834–43
N Engl J Med 2010;363:2385-95.
N Engl J Med 2009;361:1329-38.
Cardiac- resynchronization therapy for the prevention of heart- failure
events
8. Selection bias in trials
• Patients supposed to be included (Intention to
treat) vs patients actually included
• Guidelines based on Intention to treat
parameters
9. REVERSE
• 610 patients (2:1) CRT on vs off
– NYHA I & II
– QRS >120 ms, LVEF < 0.4, LVEDD > 55 mm
• Overall
– Mean LVEF 0.26, Mean QRS duration 153 ms,
– NYHA II: 83%
Funded by Medtronic
10. REVERSE (contd)
• At 12 months
– 16% worsened on CRT on and 21% in CRT off
– Absolute risk reduction 5%
– 20 patients will have to be treated for 1 year to
prevent one death or hospitalization (NNT)
• Non responders in CRT- ON
– 30%
• Complications
– 16%
11. Cost calculation – my assessment for India
• Average CRT implantation cost @ Rs. 4 lakhs
• Average device life 5 years (@ 35% required
replacement at the end of 4 years)
• Average re-implant cost @ Rs. 3 lakhs
• 10% need lead replacement/repositioning- average
cost Rs. 50000
12. REVERSE (contd)
• At 12 months
– 16% worsened on CRT on and 21% in CRT off
– Absolute risk reduction 5%
– 20 patients will have to be treated for 1 year to
prevent one death or hospitalization (NNT): Cost @
Rs. 10,000,000 (only 1 crore)
• Non responders in CRT- ON
– 30%
• Complications
– 16%
13. REVERSE TRIAL
• NYHA I: no
benefit
• NYHA II
barely
reached the
unity line
• <152 ms: no
benefit
14. RAFT
• NYHA II, LVEF <30%, QRS >120
• Overall
– 1798 patients, FU for 40 months
– LVEF: 0.22
– NYHA II: 80%
– Mean QRS duration 158 ms
– BB and ACEI in max possible dose: 90- 97%
Funded by Medtronic
15. RAFT results
- Death or hospitalisation: 33% in CRT and 40% in non-CRT (ARR 7%)
- 14 patients treated for 9 years to prevent 1 death (cost @ Rs. 1.4 crore)
- 11 patients treated for 5 years to prevent 1 hospitalisation (cost @ Rs. 66 lakhs)
- Device related hospitalization in one year: 20%
- Non responders: not mentioned
- QRS <150 ms: not benefited
16.
17. MADIT - CRT
• 1820 patients, QRS >130, EF <30%, NYHA I and II
• 3:2 (CRT-D/ICD)
• Overall
– NYHA II: 85%
– QRS duration >150 ms: 65%
– LVEF: 0.24
– BB and ACEI: 93 - 94%
Funded by Boston Scientific
18. MADIT –CRT results
• Non-responders: not mentioned
• Complication
– Total device related intervention in 30 days: 5%
• Result
– Over 2.5 years
– Death and hospitalization (17% vs 25%; ARR: 8%)
• NNT:12 patients to be treated for 2.5 yrs to prevent one death
or hospitalization (cost @ Rs. 60 lakhs)
21. Inferences
• NYHA definition: should be on maximum tolerable
dosages
• NYHA I: do not benefit
• NYHA II
• Quantum of benefit questionable
• Upto 15 patients to be treated for 2.5 to 5 years to
prevent one hospitalization or death
• Non-responders: upto 30%
• Complications: 20% in one year
• Cost - to the family ?
- to public funds ???
22. Practical issues
• Understanding of cardiac activation
• Expertise in implanting CRT
• Availability of thoracotomy option
• Ability to troubleshoot the device
• Ability to assess and program the device to get
maximum benefit
23. Is it worth it or is it overkill?
• We cardiologists are aggressive people
• Anything difficult is always challenging for us
• We say calculated risk
– Calculation by cardiologist
– Risk for the patient
• Let us be careful in our case selection so that this
therapy is maximally useful
