1. Complications in Valvular Heart Surgery
นพ.ณัฐพล อารยวุฒิกุล
ศูนย์โรคหัวใจโรงพยาบาลลำปาง

2. Technique related complications
Massive bleeding require reoperation
Heart block
Stroke
Perioperative MI
Valve dysfunction
Incomplete correction

3. Valve related complication
Thromboembolism and Bleeding
Endocarditis
Structural deterioration
Prosthetic valve thrombosis
Prosthetic-Patient Mismatch

4. Serious bleeding
Mediastinal bleeding requiring reoperation %

5. Serious mediastinal bleeding
Infant 6 kg
70 cc in first hour
60 cc in second hour
50 cc in third hour
Total 130 cc by fourth hour
Total 150 cc by fifth hour
Adult 50 kg
500 cc in first hour
400 cc in second hour
300 cc in third hour
Total 1000 cc by fourth hour
Total 1200 cc by fifth hour

6. Preoperative precautions
Aspirins
Should be stopped 1 week prior to surgery
Clopidogrel and ticlopidine
Should be stopped at least 1 week prior to surgery
NSAIDs
Should be stopped 1 day before surgery
Warfarin
Should be discontinued 3 days before surgery

7. Predisposing comorbid metabolic abnormalities
Uremia
Plt dysfunction/impaired vWf action
Plt transfusion usually not effective
Adequately dialyzed preoperatively
FFP , Cryoprecipitate and DDAVP are considered

8. Predisposing comorbid metabolic abnormalities
Acute liver dysfunction
DIC eg IE pt.
Impaired synthesis function of factor 2,7 9 10
Fibrinogen and platelets may be low
Increased fibrinolysis process
Preop vitamin K , FFP and platelets must be transfused to correct or normalize PT and platelet counts
Elevated D-dimers, thrombocytopenia, prolonged PT/PTT
In adequated heparinization during CPB leading to thrombosis in the oxygenator of the pump

9. How to prevent postoperative bleeding
Strict avoidance of hypertension
Aware of heparin rebound ( up to about 6 hrs. postop)
Anti fibrinolytic drugs
Tranexamic acid
Load mg per kg over 30 mins
Continuous infusion 1-4 mg/kg/hr over 1-12 hr.
Desmopressin(DDAVP)
Vasopressin analogue, increase factor 8 and von Willibrand’s factor
IV 0.3 microgram per kg

10. Left Ventricular Rupture
Major lethal complication of MVR
Mortality ~ 75%
Risk factors
Female sex, advanced age,small left ventricle, previous operation
Extensive retraction of papillary muscle, inadvertent injury to annulus, too large prosthesis, impingement by a valve strut and deep sutures to the myocardium

11. Left Ventricular Rupture
Ann Thorac Surg 46 Nov 1988

12. LV Rupture Type 1

13. LV Rupture Type 2

14. LV Rupture Type 3

15. Repair LV rupture

16. Repair LV rupture

17. Heart Block
Heart block requiring a permanent pacemaker ~1% following AVR and MVR

18. Heart Block
Heart block requiring a permanent pacemaker ~2-7% following TVR

19. Stroke Incidence* 4.8% in aortic valve surgery
8.8% in mitral valve surgery
9.7% in double valve surgery
*Ann Thorac 2003;Feb 75(2) 472-8
*Ann Thorac 2003;Feb 75(2) 472-8

20. Stroke Aortic plaque* Intraop palpation can detect around 50%
TEE – better than manual palpation but less sensitive in the mid and distal ascending Aorta
Epiaortic U/S – sensitivity 96.8%
*Chest 2005; 127:60-65

22. Stroke Left Atrial clot Air Cardiac vent + Aortic root vent
Intraoperative CO2 blowing 6-8 L/min
Inversion of the left atrial appendage/obliterate LAA
Tilting of the table from side to side with inflation of the lungs to dislodge any pulmonary vein bubbles
TEE

23. Stroke
Valve position (mitral versus aortic), adequacy of anticoagulation, presence of atrial fibrillation, and patient comorbidities.
Interestingly, the risk of thromboembolism appears equal regardless of whether the prosthesis is a mechanical or bioprosthetic valve.

24. Perioperative MI

25. Perioperative MI

26. Perioperative MI
(TEE) was invaluable in confirming the diagnosis in the setting of acute ventricular fibrillation and new left bundle branch block.
Iatrogenic injury to coronary arteries is a known complication of aortic valve surgery, and was the likely source of the ischemia and resultant arrhythmia.

27. Valve Dysfunction Sutures loop around the struts
Free ends of the sutures must be short and placed properly to avoid being caught in the closing prosthetic leaflets
Subvalvular tissue

28. Valve Dysfunction Periprosthetic leakage
Usually there is no different between mechanical and bioprosthetic valve

29. Predisposing factors annular calcification Infection PPM
Excessive tension on suture or annulus
Incorrect / insufficient number of sutures

30. Incomplete Correction
Residual regurgitation
Stenosis
SAM (Systolic anterior motion)

31. Systolic Anterior Motion
Adverse outcome after valve repair
Anterior leaflet obstruct LVOT
Etiology
Increased redundancy in leaflet tissue
Small annuloplasty ring

32. Systolic Anterior Motion

33. Systolic Anterior Motion
Treatment
Medical Rx if parameter of repair is good
Avoid inotropic drug except for norepinephrine
Maintain adequate preload
Surgical Rx
Posterior leaflet sliding procedure
Slightly oversized the annuloplasty ring
Use Alfieri stitch to A1/P1
Implant Gortex suture to reduce height of anterior leaflet

35. Thromboembolism and Bleeding
Major causes of thromboembolism
Interrupted anticoagulant or inadequate INR
High risk group*:
Prior embolic complications AF
Left atrial thrombus
Recent operation ( first operative year )
Operation before the mid 1970s

36. Thromboembolism MVR – more common due to AF and large LA
AF – important factor for thromboembolism
Multiple valve replacement  higher embolic rate

37. Anticoagulant-related Hemorrhage
Incidence
- 1%-4% per person year
- same rate in MVR and AVR
- Risk: increase in INR > 4.0

38. Prosthetic Valve Endocarditis
Early - within 2 months
- incidence 1% per patient/year
- mortality 50%-70%
- highly destructive process
valve ring abscess & paravalvular leaks and conduction disturbances

39. Prosthetic Valve Endocarditis
Early PVE has higher mortality rate ( 75% VS 43% ) due to
Predominance of nonstreptococcal mechanisms
More debilitated patients
Involve freshly implanted, nonendothelialized valve and sewing ring

41. Prosthetic Valve Endocarditis
Late - more than 2 months
- Source of infection : Dental and Genitourinary tract
- Mechanical  sewing cuff
- Bioprosthesis  cusps(leaflets)
less at sewing cuff
paravalvular leaks rare

42. Prosthetic Valve Endocarditis
Indication for Surgery
Early prosthetic valve endocarditis (first 2 mo)
Heart failure with prosthetic valve dysfn
Evidence of perivalvular extension
Persistent infection after 7-10 d of adequate ATBs
Recurrent emboli despite appropriate ATBs
Infections due to organisms with poor response ATBs
Obstructive vegetation

43. Structural Deterioration
Bioprosthetic Valve Failure
- freedom from valve deterioration for the two most commonly used bioprosthesis valve ( Carpentier-Edward and Hancock ) is between 60% and 80% at 10 years and drops sharply to 45% at 14 years
- Mitral valve  higher rate of failure

44. Prosthetic valve thrombosis
Any obstruction of a prosthesis by non infective thrombotic material
Incidence:
0.5-8% in Lt. sided mechanical Valve
20% in tricuspid position
Thrombosis %
Pannus %
Pannus + Thrombosis %
Mitral position  more frequent than aortic position

45. Prosthetic valve thrombosis
Obstructive PVT  abnormal dyspnea,
heart failure
Non-obstructive PVT  embolic episode
Echo findings:
Abnormal movement of prosthesis
Paraprosthetic thrombus
Abnormal transprosthetic flow
Mitral gradient > 8 mmHg, effective area < 1.3 cm2
Aortic mean gradient > 40 mmHg
Heart 2007;93:

46. Prosthetic valve thrombosis
Surgery
Mortality: 4% in pt with FC I-III
17.5% in pt with FC IV
Thrombolysis: success 82%
mortality 10%
systemic emboli 12.5%
bleeding 2-5%
J.Heart Valve Dis Vol.14. No.5. Sep 2005

47. Prosthetic valve thrombosis
Emergency operation is reasonable for patients with a thrombosed left-sided prosthetic valve and NYHA functional class III-IV or a large clot burden (IIa level C)
Fibrinolytic therapy is reasonable for thrombosed right-sided prosthetic heart valves with NYHA class III-IV or a large clot burden (IIa level C)
ACC/AHA Practice Guidelines 2006

48. Prosthetic valve thrombosis
Fibrinolytic Rx may be considered as a first-line Rx for patients with a thrombosed left-sided prosthetic valve, NYHA class I-II, and a small clot burden (IIb level B)
Fibrinolytic Rx may be considered as a first-line Rx for patients with a thrombosed left-sided prosthetic valve, NYHA class III-IV or a large clot burden if Sx is high risk or not available (IIb level C)
ACC/AHA Practice Guidelines 2006

49. Prosthetic valve thrombosis
Intravenous UFH as an alternative to fibrinolytic therapy may be considered for patients with a thrombosed valve who are in NYHA class I-II and have a small clot burden (IIb level C)
ACC/AHA Practice Guidelines 2006

50. Which type of valve to be selected
Risks of anticoagulant-related bleeding
Risks of structural failure
Risk of reoperation
Underlying medical or surgical problems

51. Prosthetic-Patient Mismatch
Prevention
- Implant another type of prosthesis with large EOA such as stentless valve
- Enlarge the aortic root

52. Thank you
for
your attention