Implantation thoracoscopique

Introduction

Transvenous pacemaker implantation is safe

• All dogs survived implantation in studies ^[1] and ^[2], 6 cardiac arrest in ^[3]
• Major complications (15/104, Johnson and al. – 12/105, Wess and al., 51/136 Oyama and al.)
• Lead displacement >>> infection, bleeding

Transvenous pacemaker implantation is successful in reducing clinical signs in sick sinus syndrome or third degree atrioventricular block

• Mean survival times (2,2 years Wess and al.)
• One-, three and five years survival : 86%, 65%, 39% (Johnson and al.)
• One, two and three years survival : 70 %, 57 %, 45 % (Oyama and al.)

→ Gold Standard

^[1] Results of pacemaker implantation in 104 dogs, M.S. Johnson, M.W.S Martin, W Henley, (2007) JSAP 48:4-11
^[2] Applications, complications and outcomes of transvenous pacemaker implantation in 105 dogs (1997-2002), G Wess, W.P. Thomas, D.M. Berger, M.D. Kittleson, (2006) J Vet Intern Med 20(4):877-84
^[3] Practices and outcomes of artificial cardiac pacing in 154 dogs, M.A. Oyama, D.D. Sisson, L.B. Lehmkuhl (2001), J Vet Intern Med 15(3):229-39

Interests of transvenous pacemaker implantation

• Minimally invasive

Limits of transvenous pacemaker implantation :

• Injury / sepsis in the area of right jugular vein
• Price
• Available
• NO SURGEON NEEDED

Study design

Prospective case serie

Animals

• Sick sinus syndrome (1), Sinoatrial block (1),
• Atrioventricular block and non active or old myocarditis suspected (2)

Cadaveric study conducted to compare the epicardial access for implantation

Procedure

Dogs randomly assigned to:

- group 1 = conventional Trans-diaphragmatic approach(TDA)

- group 2 = Thoracoscopic implantation (TI)

• Dorsal recumbancy
• 5 mm telescope / paraxyphoïd approach
• Instruments portals en in 6th intercostal space – left 15mm – Right 5 mm
• Pericardial window
• Myocardic biopsy

 

Photos 1&2: Thoracoscopic pericardectomy performed without pulmonary exclusion in 9 dogs.
Dupré G, Corlouer J, Bouvy B (2001). Vet Surg 30(1)21-7

Leads

• Medtronic Unipolar electrodes for single chamber pacing
• Capsure EPI 4965 coated with steroïds
• Suturelessunipolar myocardial screw-in pacing lead

• Pulse generator : VVIR Medtronic ADAPTA ADSR 01

 

• 15 mm portal for lead implatation
• Lead and electrode positionning
• Controle pacing

 

 

Anatomic study

• Both procedures done on a cadaver
• Epicardium marked on the insertion sites by Ligasure
• Full heart dissection

 

Results

- Animals

- Surgical time

• 46’ and 43 ‘ in Group 1
• 44’ and 22’ in Group 2

- 1 major complication in Group 2 case 2

• Pigtail loss, thoracoscopic reimplantation neededTwiddler syndrome

- Biopsy

• Old myocarditis confirmed in both cases of Group 2
• Biopsy had no consequence on cardiac pacing

- Outcomes

• Hospital discharge 3 and 4 days PO in group 1 1 and 2 days PO in group 2
• All dogs free of cardiac symptomes